Patent Application
20180057837
The invention (embodiments) relates to the field of medicine, pharmacology, biotechnology, molecular biology, genetic engineering and can be used for analgesia.
It is important to recognize that pain is not just an indicator of the underlying disease or damage process, it is an independent problem, causing great damage to individuals and society in whole. To improve the quality of life pain relief as such should be the therapeutic goal. A promising approach to the treatment of pain, which is proceeded to currently,—the identification of the mechanism and implementation of targeted (aimed at specific molecules) pharmacological therapy [WHO Normative Guidelines on Pain Management, Geneva June 2007].
Peptide amides [U.S. Pat. No. 4,459,225 (A)], phenylhydrazone derivatives are known to be used as anti-inflammatory or analgesic agents [EP0952159 (B1)], synthetic peptide amides—for the prevention and treatment of pain [RU2500685C2]. A family of peptides is known to be used possessing analgesic activity, of the general formula A-B-Tyr-Pro (DPro, dHPro, DdHPro, DLdhPro, Hyp)-C-X [WO2008020778 (A1)], a derived peptide is known to be used which is administered subcutaneously or orally possessing analgesic or anti-nociceptive activity [US2008009448 (A1)].
The disadvantage of chemically synthesized peptides and their derivatives is the ability to obtain a mixture of the desired compounds with enantiomers which may lead to unpredictable results. The concept of enantiomeric plays an important role in pharmaceutics because different enantiomers of drug substances usually have different biological activity. The use of living systems for obtaining peptide molecules allows to obtain the molecules of natural structure, a homogeneous mixture.
A recombinant plasmid is known, for bacterial expression, containing a homologous regulon or heterologous DNA, the least may encode a polypeptide with analgesic effect [SK278170 (B6)]. A mono-coupling of the indole with a new structure is known containing deep macrogenomic gene cluster, synthesized in Escherichia coli cells [CN102477436 (A)]. A polypeptide is known from the sea anemone Heteractis crispa, which has strong analgesic effect [RU2368621C1, RU2404245C1], and its preparation method [RU2415866C1]. Peptides are known with a large number of bridging ties, isolated from ACTINOMADURA NAMIBIENSIS, for the treatment of neuropathic pain caused by inflammation [RU2498995C2]. However, due to the fact that these molecules are derived from organisms that are distant from a human, their effect must be studied very carefully before use in a human.
A hybrid protein on the basis of conotoxin (snail poison) MVó A and Trx is known, which can be used in the preparation of pain meds for the last stages of cancer and AIDS, post-operative pain, burns, etc. [CN1487085 (A)]. A method of obtaining conotoxin using baculovirus and insect cells or insects is known [CN102876683 (A)]. Methods of analgesia and improved opiate analgesia introduction with omega-conopeptides TVIA (SNX-185) or MVIIA (SNX-111) introduction [EP0625162 (B1)], methods of analgesia using alpha conotoxins [WO2014023129 (A1), CN102286079 (B), CN103374066 (A)], Lt7b conotoxin [CN102628048 (A)] are known. It is known to use omega-conopeptide for the production of medicament for inhibiting the progress of neuropathic pain [EP1336409 (B1)]. A Scorpio polypeptide is known having analgesic and antitumor activity [U.S. Pat. No. 7,592,309 (B2), CN101591668 (A)], and a method of its application [U.S. Pat. No. 7,592,309 (B2) and CN101591668 (A)], a scolopendra Scolopendra subspinipes mutilans one—mu-SLPTX-Ssm6a—having an analgesic effect [CN102977201 (A)]. Peptides of the venom of the spider Grammostola spatulata, with analgesic effect [U.S. Pat. No. 5,776,896 (A)], a peptide HWAP-I of a Chinese tarantula [U.S. Pat. No. 6,670,329 (B2)] are known. Peptide molecules from snake venom and their derivatives, homologs, analogs and mimetics are known capable of inducing analgesia or alleviating pain alone or in combination with other analgesic molecules [U.S. Pat. No. 6,613,745 (B1), U.S. Pat. No. 7,902,152 (B2)], and also a shortened neurotoxin of the sea snake Lapemis hardwickii is known for analgesia [U.S. Pat. No. 7,294,697 (B2)].
The disadvantage of that group of inventions is that the use of toxins, even pharmaceutically pure, is still a risk—in case of overdose up to death.
A new polypeptide is known to be used—a subunit 9.01 [CN1345751 (A)], subunit 12.65 [WO00212310 (A1)], subunit 9.46 [WO00204504 (A1)], subunit 11.44 [CN1352195 (A)] of human G-protein for analgesia. Polypeptides are known based on a G-protein receptor HFIAO41 [US2001016336 (A1)], HLYAZ61 [EP0837128 (A2)], HUVCT36 [U.S. Pat. No. 5,912,335 (A)], H7TBA62 [U.S. Pat. No. 5,955,309 (A)], org10 [US2003162945 (A1)], org11 [WO0200725 (A2)] and also belonging to the family IGS4 [AU779993 (B2), U.S. Pat. No. 6,998,255 (B1)]. Variants of a spliced G-protein receptor induced by Epstein-Barr EBI 3 are known [U.S. Pat. No. 5,874,252 (A)].
Methods of treatment of pain caused by bone cancer, osteoarthritis, postoperative pain are known by administering of antagonist of nerve growth factor (antibodies) [RU2389509C2, RU2429013, RU2338555C2], partners of specific binding with this molecule are known [RU2406728C2]. It is shown that molecules capable of inhibiting the binding between TrkA receptor and NGF can be used as analgesics with a prolonged effect [RU2427387C2]. Antibodies against nerve growth factor are known having increased stability in vivo [RU2011149263A], high affinity for NGF [RU2473564C2], and a dosage form is known of a humanized antibody against the growth factor of nervous tissue [RU2427387C2].
Known methods of treatment of:
Methods of reducing pain sensitivity in physiological and pathophysiological conditions (for example, in allodynia and hyperalgesia) are known, especially of pain perception that is associated or mediated by mechanical sensitivity via TRPA1, using a TRPA1 antagonistic antibodies, preferably monoclonal antibodies [RU2430750 C2]. Analgesic/anti-inflammatory agents are known selected from the following classes of receptor antagonists, receptor agonists and enzyme inhibitors, each class acting by different molecular mechanisms of action on pain and suppression of inflammation: (4) bradikinin receptor antagonists (peptides), antagonists of calcitonin gene-mediated peptide (CGRP) receptor (alpha-CGRP-(8-37), (8) antagonists of interleukin receptor (Lys-D-Pro-Thr) [RU2180852 C2], of beta-cellulin (BTC) protein [JP2000198744 (A)]. Methods are known of reduction of the pain of CRF2R modulated disorder using agonists of corticotropin-releasing factor (CRF 2R) receptor [RU2385878C2], treatment of pain with the use of a peptide having properties of amilin [RU2385878C2], of NOP peptide agonist [RU2012106820A], of peptides containing two and more amino acid residues of the 11-28 fragment of vasoactive intestinal peptide (VIP), delivered in the CNS [WO9104041 (A1)], of a derived peptide on the basis of calcitonin [U.S. Pat. No. 5,446,026A], human polypeptides CGRP-RCF [U.S. Pat. No. 5,710,024 (A), WO9803534 (A1)], polypeptides—humanized CGRP receptor, including for the treatment of headache, chronic headache of tension, severe paroxysmal headache with periodic recurrence, prevention of migraines [U.S. Pat. No. 7,193,070 (B2)], polypeptides—new spliced options of human 11cb [U.S. Pat. No. 6,033,872 (A)], agonists and antagonists of the latter protein [WO9928492 (A1)], receptors with seven transmembrane domains [U.S. Pat. No. 5,824,504 (A), U.S. Pat. No. 6,277,960 (B1), U.S. Pat. No. 6,277,977 (B1), U.S. Pat. No. 5,955,308 (A), U.S. Pat. No. 6,221,627 (B1), US2002106766 (A1), U.S. Pat. No. 5,994,098 (A), U.S. Pat. No. 6,174,994 (B1), U.S. Pat. No. 6,037,146 (A), U.S. Pat. No. 5,874,243 (A)], a peptide having phosphodiesterase activity [WO0166716 (A1)], polypeptides—human protein kinases hYAK3 and HOACF72 [EP0870825 (B1) and U.S. Pat. No. 5,972,606 (A), respectively].
A hybrid protein based on brain neurotrophic factor is known produced using prokaryotic soluble protein expression system [CN1978466 (B), WO9942480 (A1)]. Polypeptides are known based on receptor of neurotensin of type 2 for the treatment of pain [U.S. Pat. No. 6,008,050 (A)]. A conjugate of neurotensin or its analogues with therapeutic peptide is known, which can be used to induce hypothermia or analgesia [WO2010063122 (A1)]. Conformationally optimized analogues of alpha-melanotropin are known, which have a specific effect on the CNS [U.S. Pat. No. 4,649,191 (A)]. A synthetic peptide for modulation of the release of the neurotransmitter similar to SNARE is known [KR20090041066 (A)].
Peptides are known with multiple functions, including analgesia, such as peptides with a large number of bridging, extracted from Actinomadura namibiensis [RU2010144778A], a peptide of structure DGSVVVNKVSELPAGHGLNVNTLSYGDLAAD [RU2508296C2], a peptide modulator of purinergic receptors PT1 [RU2422459C1], dipeptides containing a 2-thioacyl group on an N-terminal amino acid residue as inhibitors of vasopeptidase [RU2298559C2], thymus-specific protein [RU2398776C2], a polypeptide improving calcium metabolism [JPH03178993 (A)] as well as prodrug compositions with a high degree of penetration based on peptides and compounds related to peptide [RU2011149796 A].
A combined approach to analgesia is known using a synergistic combination of a selective inhibitor of the neuronal norepinephrine transporter and an analgesic in the therapeutic treatment of vertebrates, including humans, for anesthesia or for the prevention or relief of pain [U.S. Pat. No. 8,188,048 B2]. Peptides-analogues of dynorphin are known that, when co-administered with a narcotic or analgesic, reinforce the latter, including enkephalins and beta-endorphin analogues [EP0096592B1].
Methods are known of increasing the pharmacological activity of the substances with oral and parenteral administration of the compositions, with the use of the peptide Tyr-Gly-Gly-Phe-Met bound with a carrier group, thus forming a precursor of a drug used in the treatment or relief of pain [AU2002228260 (B2)].
The use of one highly effective agent for analgesia, simple and cheap to produce, is a more cost-effective option.
A use of defensin peptide Hnp-1 is known, one or in combination with neuropeptide M, as a therapeutic agent for the prophylaxis and/or treatment including peripheral vascular diseases, including anesthesia, spreading pain, causalgia (burning pain) [WO 2009/043461 A1].
The use of molecules of protein nature, which were not thought of as inducers of the immune response, including antibody, can be complicated by these very effects, which may lead to side effects, for example, associated with the formation of autoantibodies.
A use of small interfering RNA and of a short hairpin RNA is known for gene knockdown of NR1 subunit of N-methyl-D-aspartate subcutaneous receptor to reduce the inflammatory pain or intolerable chronic pain, especially chronic clinical pain and pain caused by burns [U.S. Pat. No. 8,372,817 (B2), U.S. Pat. No. 8,575,330 (B2), U.S. Pat. No. 8,361,985 (B2)]. RNA interfering agent is known for the treatment of chronic pain [WO2013126963 (A1)]. However, the preparations of RNA are quickly destroyed outside of the body, special storage conditions are required, which sets industrial applicability of drugs based on RNA a question.
A method of long-term analgesia is known in which the patient is injected with myogenic cells, in which from a corresponding DNA a peptide is synthesized that activates an opioid receptor or mediates the binding of substance P to the receptor [U.S. Pat. No. 7,166,279 (B2)]. However, the implementation of this method is quite complicated and is associated with many risks.
Methods of treatment of depression and pain are known, the agent may be a protein, RNA or DNA [WO2013177484 (A1)]. Lentiviral vector for the treatment of pain containing G-protein of rabies virus [EP1425403 (B1)], adenovirus encoding IL-24 [CN101518655 (A)], including for pain relief when cancer are known. Oncostatin M is known, or its homologue, synthesized from a vector for transfer of genes: lentivirus, retrovirus, Sendai virus, adenovirus and adeno-associated virus, including for the treatment of pain [JP4803789 (B2)]. Treatment of allodynia, hyperalgesia, spontaneous pain and phantom pain using kometin is known—polypeptide, which can be delivered as a polypeptide, or by introduction of expression vector for expression of kometin, a cell line, transformed or transfected with the protein and a capsule containing the cells [WO2013034157 (A1)]. Viral vectors have disadvantages, including the fact that they are expensive and can cause inflammatory response that precludes repeated administration of the vector. Viral vectors can replicate, which reduces the degree of control over expression of the targeted protein, which in turn is not always desirable and applicable, particularly in relation to analgesia.
A recombinant DNA-vaccine based on a pVAX1 vector is known, targeted to a tumor, including for the treatment of pain in oncology that contains a gene encoding cyclooxygenase-2 (COX-2), murine ubiquitin Mubi, as well as ISS immunostimulatory sequences of DNA (pVAX1-mUbi-ISS-COX-2-ISS) [CN101648011 (A)]. However, this design is aimed to induce an immune response, cytotoxic, for which elements are introduced that lead to and increase immunogenicity.
A pharmaceutical composition is known, which contains a vector, including a plasmid DNA, and a pharmaceutically acceptable excipient or adjuvant to alleviate, prevent or treat pain, the vector contains a nucleotide sequence containing at least one area modulating the expression of the VR1 receptor [US2006154886 (A1)]. In this case analgesia is via blocking of a receptor associated with an ion channel—a nonspecific cation conductor. The use of plasmid DNA bearing a gene from which in mammal cells defensin is synthesized as a means of inducing analgesia will also help to minimize the possibility of the development of pathogens in the body: usually when the pain of any etiology the state of health worsens, and the body's ability to resist infections decreases, and as a result, after, for example, surgery, antibiotics can be prescribed, and the use of natural antimicrobial peptide will allow to combine analgesia and a protective effect, as a result, it is possible to refuse to take antibiotics.
Close analogues of the proposed invention are the inventions described in the patent CN101648011 (A) and the application for the invention US2006154886 (A1), which disclose analgesics in the form of plasmid DNA.
It is shown that when intramuscular injection of DNA, expression vector is absorbed by muscle cells, and expression of an encoded gene in the input vector is performed [J. A. Wolff et al., Science 247, 1465 (1990); G. Ascadi et al., Nature 352, 815 (1991)]. It is shown that the plasmids are maintained as episome and do not replicate. A constant expression has been demonstrated after intramuscular injection also in the skeletal muscles of rats, fish and primates, and cardiac muscle of rats [H. Lin et al, Circulation 82, 2217 (1990); R. N. Kitsis et al, Proc. Natl Acad. Sci. (USA) 88, 4138 (1991); E. Hansen et. al, FEBS Lett. 290, 73 (1991); S. Jiao et al., Hum. Gene Therapy 3, 21 (1992); J. A. Wolff et al, Human Mol. Genet. 1,363 (1992)]. The use of other technologies of delivery of a plasmid DNA into cells of various tissues is known, for example, of a needleless syringe, allowing for the delivery into cells of various tissues of living animals [Furth et al., Analytical Biochemistry, 205, 365-368, (1992)].
It is shown that normally muscle fibers do not express MHC antigens, but during the inflammation associated with the infection, or in the presence of interferon gamma muscle fiber is capable of producing antigens in the complex with the first class MHC or even second class [MECKERT, P. C, HONTEBEYRIE-JOSKOWICZ, M., CHAMBO, J., LEVIN, M., and LAGUENS, R. P. (1991). Trypanosoma cruzi: Aberrant expression of class II major histocompatibility complex molecules in skeletal and heart muscle cells of chronically infected mice. Exp. Parasitol. 72, 8-14; Hohlfeld and ENGEL, A. G. (1984) The immunobiology of muscle. Immunol. Today 15, 269-274.; MANTEGAZZA, R. & BERNASCONI, P. (1994). Cellular aspects of myositis. Curr. Opin. Rheumatol. 6, 568-574, Hartikka J, Sawdey M, Cornefert-Jensen F, Margalith M, Barnhart K, Nolasco M, Vahlsing H L, Meek J, Marquet M, Hobart P, Norman J, Manthorpe M. An improved plasmid DNA expression vector for direct injection into skeletal muscle. Hum Gene Ther. 1996 Jun. 20; 7(10):1205-17], in this connection, the introduction of a plasmid DNA in which the injury to the muscle is minimized is preferred.
It is shown that even being immunogenic in tests on laboratory animals, in humans formulations based on a plasmid DNA are not immunogenic [Saade F, Petrovsky N. Technologies for enhanced efficacy of DNA vaccines. Expert Rev Vaccines. 2012 February; 11(2):189-209. doi: 10.1586/erv.11.188]. The researchers also failed to find evidence of pathological changes after the repeated injections of DNA in mice or rabbits [Parker S E, Borellini F, Wenk M L, et al. Plasmid DNA malaria vaccine: tissue distribution and safety studies in mice and rabbits. Hum. Gene Ther. 1999; 10(5):741-758.]. In 2007, in the U.S. FDA guidance on DNA vaccines concluded that preclinical studies are not required to assess the effect against autoimmune diseases.
A plasmid DNA should contain elements essential for organisms of its maintenance and use, together with appropriate regulatory sequences. Regulatory sequences are nucleotide sequences that can affect gene expression at the level of transcription and/or translation, as well as mechanisms ensuring the existence and maintenance of the functioning of the plasmid DNA.
For prokaryotic system origin of replication and a reporter gene are essential. Bacterial elements of the plasmid DNA are not to negatively influence expression in mammalian cells and cause side effects from the use of the plasmid DNA. In the literature, there is evidence that the use of a gene of resistance to ampicillin as a reporter gene may be undesirable in connection with the development of the reaction in patients on ampicillin, but the authors consider such effects associated with a low quality of purification of a plasmid DNA, but not by the element itself.
Essential elements of plasmids for use in mammals are a promoter, an mRNA leader sequence, a termination sequence.
A promoter is an important component of the plasmid, which triggers the expression of a gene of interest. Classic promoters for plasmid DNA—components of drugs—is a human CMV/immediate-early or CMV-chicken-β actin (CAGG) promoter. CMV promoters are used for the most DNA vaccines, as they mediate high levels of constitutive expression in a wide range of mammalian tissues [Manthorpe M, Cornefert-Jensen F, Hartikka J, et al. Gene therapy by intramuscular injection of plasmid DNA: studies on firefly luciferase gene expression in mice. Hum. Gene Ther. 1993; 4(4):419-431] and do not inhibit the downstream reading. The increase in expression level is observed when changing the CMV promoter, for example, by the inclusion of HTLV-1R-U5 downstream from the cytomegalovirus promoter or using a chimeric SV40-CMV promoter [Williams J A, Carnes A E, Hodgson C P. Plasmid DNA vaccine vector design: impact on efficacy, safety and upstream production. Biotechnol. Adv. 2009; 27(4):353-370]. Tissue-specific host promoters serve as an alternative to the CMV promoter, they allow to avoid constitutive expression of antigens in inappropriate tissues, which generally leads to lower immunogenicity [Cazeaux N, Bennasser Y, Vidal P L, Li Z, Paulin D, Bahraoui E. Comparative study of immune responses induced after immunization with plasmids encoding the HIV-1 Nef protein under the control of the CMV-IE or the muscle-specific desmin promoter. Vaccine. 2002; 20(27-28):3322-3331].
The leader mRNA sequence also plays a big role. The Kozak sequence directly before the start codon ATG allows to increase the expression [Kozak M. Recognition of AUG and alternative initiator codons is augmented by G in position +4 but is not generally affected by the nucleotides in positions +5 and +6. EMBO J. 1997; 16(9):2482-2492]. The presence of an intron in the plasmid downstream from the promoter can increase the stability of mRNA and enhance the gene expression.
The use of species-specific codons allows to increase the expression of the gene [Frelin L, Ahlen G, Alheim M, et al. Codon optimization and mRNA amplification effectively enhances the immunogenicity of the hepatitis C virus nonstructural 3/4A gene. Gene Ther. 2004; 11(6):522-533].
Gene expression can be influenced by changing the terminating sequence, which is needed to preserve the stability of mRNA, for the proper termination of transcription and export of mRNA from the nucleus, including its shortening. Many of today's DNA vaccines use the sequence of the transcription terminator of bovine growth hormone [Montgomery D L, Shiver J W, Leander K R, et al. Heterologous and homologous protection against influenza A by DNA vaccination: optimization of DNA vectors. DNA Cell Biol. 1993; 12(9):777-783]. Polyadenylation (polyA) is required for stabilization of the transcript. Changing of the polyA sequence can lead to the increase of gene expression level [Norman J A, Hobart P, Manthorpe M, Felgner P, Wheeler C. Development of improved vectors for DNA-based immunization and other gene therapy applications. Vaccine. 1997; 15(8):801-803]. In pVAX1 (Invitrogen, Carlsbad, Calif.) a terminator region of bovine growth hormone contains a homopurine fragment, which is sensitive to the nuclease. It is shown that alternative polyA sequence can significantly improve the stability of the plasmid to a nuclease [Azzoni A R, Ribeiro S C, Monteiro G A, Prazeres D M F. The impact of polyadenylation signals on plasmid nucleases-resistance and transgene expression. J Gene Med. 2007; 9:392-402]. The introduction of two stop codons allows to increase the efficiency of the transcription terminator.
The optimal plasmid design for the implementation of the function should combine the “bacterial” and “eukaryotic” elements with appropriate regulatory sequences to ensure a high number of copies per cell during the production process and a high level of expression in mammals [Saade F, Petrovsky N. Technologies for enhanced efficacy of DNA vaccines. Expert Rev Vaccines. 2012 February; 11(2):189-209. doi: 10.1586/erv.11.188].
To create analgesics according to the present invention it is possible to use a plasmid DNA, as a minimum, standardly used for gene delivery and expression in the mammals, including humans, and also optimized on the above parameters, including those described in detail in Williams et al., 2009 [Williams J A, Carnes A E, Hodgson C P. Plasmid DNA vaccine vector design: impact on efficacy, safety and upstream production. Biotechnol. Adv. 2009; 27(4):353-370]. In the FDA guideline (2007) it is stated that studies of the biodistribution of a substance after its introduction in the body can be waived for DNA vaccines produced by cloning of a new gene into a plasmid vector, for which acceptable biodistribution and integration profile are documented previously. In the WHO guideline (2007) it is stated that research on the biological distribution and conservation is required if there is no considerable experience of work with almost identical or similar product. In the EMEA guidance (2006) it is stated that the experience of work with the vector system will allow to optimize and focus on preclinical studies. Safety studies with the use of DNA vectors with different cloned genes showed similar biodistribution [Sheets R L, Stein J, Manetz T S, Duffy C, Nason M, Andrews C, Kong W P, Nabel G J Gomez P L. Biodistribution of DNA plasmid vaccines against HIV-1, Ebola, Severe Acute Respiratory Syndrome, or West Nile virus is similar, without integration, despite differing plasmid backbones or gene inserts. Sheets R L, Stein J, Manetz T S, Duffy C, Nason M, Andrews C, Kong W P, Nabel G J Gomez P L. Toxicol Sci. 2006 June; 91(2):610-9. Epub 2006 Mar. 28.] and toxicology [Sheets R L, Stein J, Manetz T S, Andrews C, Bailer R, Rathmann J, Gomez P L. Toxicological safety evaluation of DNA plasmid vaccines against HIV-1, Ebola, Severe Acute Respiratory Syndrome, or West Nile virus is similar despite differing plasmid backbones or gene-inserts. Toxicol Sci. 2006 June; 91(2):620-30. Epub 2006 Mar. 28]. For a plasmid DNA for use in mammals other than humans the requirements are less stringent, therefore it is possible to use a wider range of plasmids.
For DNA intended for human use, it may be useful to have the final DNA product in a pharmaceutically acceptable carrier or a buffer solution. Pharmaceutically acceptable carriers or buffer solutions are known from the art and include those described in various texts, such as Remington's Pharmaceutical Sciences.
The prototype of the embodiments of the invention is the invention disclosed in a patent application published as WO 2009/043461 A1: application of defensin HNP-1 for the treatment including pain.
Defensins constitute a large family of low molecular weight (3-5-kDa) cysteine-rich cationic peptides stabilized by several (usually three) disulfide bonds [Ganz, T. 2002. Immunology: Versatile defensins. Science 298: 977-979, Lehrer, R. I. and Ganz, T. 2002. Defensins of vertebrate animals. Curr. Opin. Immunol. 14: 96-102.], which are capable of killing a broad spectrum of pathogens, including various bacteria, fungi and enveloped viruses. In humans this family is represented by α-subfamily (HNP) and β-subfamily (hBD) of defensins. Alpha-defensins are mostly represented in neutrophils and Paneth cells. HNP-1 and HNP-3 contain 30 amino acid residues in total, these peptides are identical to each other except for the substitution of alanine for asparagine in position 1. HNP-2 is a proteolytic product of HNP-1 and HNP-3, contains 29 amino acid residues (missing the first amino acid from the N-terminus). The presence of disulfide bonds ensures saving of the stability of the defensin molecules to numerous leukocyte and microbial proteinases and saving antibiotic properties in the center of inflammation and tissue destruction [O. Levy Antimicrobial proteins and peptides: anti-infective molecules of mammalian leukocytes. J. of Leukocyte Biology. 2004; 76: 909-926]. For these molecules to be obtained in a correct spatial structure is quite challenging.
Genes encoding defensins form a cluster at the locus P22-23 on the 8th chromosome. HNP 1-3 are encoded by two genes HDEFA1 and HDEFA3. Each defensins gene contains several exons that encode prepropeptide.
First, defensins are synthesized in the form of precursors, as prepropeptides, the length of which is 94 amino acid residues. Prepropeptides contain the signal fragment (an average of 19 amino acid residues), anionic fragment (an average of 45 amino acid residues) and the “mature” peptide. In the result of a proteolytic cleavage in the endoplasmic reticulum from a prepropeptide a removal of the signal fragment and a prodefensin formation are performed (at average 75 amino acid residues). Subsequent maturation (cleavage of 45 amino acid residues) occurs in the mature neutrophils granules. α-Defensins were also found in NK cells, B-lymphocytes, γδ T-lymphocytes, monocytes/macrophages and epithelial cells [A. S. Budikhina, B. V. Pinegin. Defensins—multifunctional cationic peptides of the person. Immunopathology, Allergology, Infectology. 2008, No. 2:31-40]. The authors of the present invention at first demonstrated that the introduction of a plasmid DNA carrying the gene encoding HNP-1/HNP-2/HNP-3 leads to analgesia, moreover, in this case the increase of the level of beta-endorphin in the serum was observed.
The disadvantages of analogues and the prototype are shown directly after their description. The claimed invention (embodiments) is free from these disadvantages.
The technical result from the use of embodiments of the invention is expressed, firstly, in expanding the spectrum of analgesics. When poor tolerability or intolerance of analogues a representative of the proposed versions of the analgesic would allow analgesia, due to which the patient will have the opportunity to take actions that he could not, or did not want to carry out without analgesia, for example, to dare on a needed procedure, as well as improve the quality of life, for example, will get less discomfort than without the use of analgesic, or will be able to alleviate acute or chronic pain. This technical result is achieved by the use of analgesic according to the present invention (embodiments).
In addition, the technical result is to increase the duration of analgesia and is achieved by the plasmid DNA use, from which after the introduction into the body alpha human defensin HNP-1/HNP-2/HNP-3 is synthesized; and by the fact that the nucleotide sequence encoding the human defensin, contains elements that lead to mRNA stability and, consequently, increases the half-life time of mRNA, as a result, the protein synthesis from one molecule of mRNA is carried out more number of times, and also as a result the amount of protein synthesized increases; and also the fact that the nucleotide sequence of human alpha defensin is codon-optimized for expression in mammals, as a result the protein synthesis is more intensive. During implementation into practice this will allow to significantly reduce the amount of plasmid DNA introduced (in 10-50 times) in comparison with the doses currently used in a blighty and world practice in gene therapy.
In addition, the technical result is to increase the safety of analgesia. This technical result is achieved by the fact that the active ingredient is not a protein to which antibodies can be formed, which, when a molecule of the original organism is used, can cause serious side effects, but a plasmid DNA, which exists as an episome and does not integrate into the genome, from which the human protein is synthesized and then secreted, and as a result, a nonimmunogenic, safe use of human defensin for analgesia is performed. This technical result is also achieved by the fact that the protein synthesized in the organism from the plasmid DNA undergoes natural post-translational processing, and the correct folding of the protein due to cellular chaperones is also ensured. These modifications are difficult to achieve during the production of proteins, which can dramatically affect a number of their functions. This technical result is also achieved due to the fact that natural mechanisms of metabolism and catabolism of the active substance are used, without the formation of toxic products, due to the nature of the plasmid construct and the encoded protein, as well as the identity of the protein formed to the endogenous analogue. This technical result is also achieved by the fact that the plasmid DNA does not replicate after introduction into the mammalian organism, which allows to control the amount of a synthesized protein, and, accordingly, over analgesia. This technical result is also achieved by the presence of such regulatory sequences as the silencer and/or insulator in the plasmid DNA, in one embodiment of the invention, which allows also to control the amount of the protein synthesized, and, basically, the synthesis of the protein as such, and, respectively, analgesia: if necessary, there is an opportunity in a short period to stop or decrease the expression of the gene. In the latter variant, it is also possible to perform tissue-specific expression when necessary.
The technical result is also to simplify and reduce the cost of producing the analgesic by avoiding the complexities of production and the processes of protein preparations purification in vitro, due to the fact that the protein synthesis occurs in vivo. Production, purification and storage of DNA preparations are more economically profitable than of protein ones, since the former are more stable, they can be produced in large quantities and at lower cost.
It was shown that the change in the concentration of beta-endorphin in the blood plasma is directly dependent on the type of pain syndrome, its intensity and analgesia efficiency, which can serve as a criterion for assessing the effectiveness of analgesia [Beta-endorphin—an analgesic effectiveness marker for acute pain and chronic pain syndrome in cancer Patients/ZV Pavlova [and others]//Problems of Clinical Medicine.—2007.—N1.—P. 36-40.—ISSN 1817-8359]. When the analgesic of the present invention was administered, an increase in the serum beta-endorphin level was observed (
According to the temporal characteristics, two types of pain can be distinguished:
With the use of this analgesic the both described types of pain may be relieved and eliminated. As can be seen from the prior art, a plasmid analgesic, from which in mammalian cells human alpha defensin is synthesized, is unknown. The multiplicity and nature of the elements of a plasmid DNA require clarifying characteristics. The description of the invention, in the part “the summary of the invention”, in the part “detailed description of the invention” explains “the formula of the invention” and includes a detailed description of essential elements of a plasmid DNA, which allows to implement the invention with all its embodiments, thereby achieving the described technical result.
A plasmid DNA is proposed for a transient expression in mammalian cells, represented by a skeleton that contains prokaryotic elements, origin of replication and a reporter gene, and eukaryotic elements, a strong promoter, a leader mRNA sequence and regulatory sequences for these elements, at least one site to clone the gene of interest and at least one of site for at least one primer annealing for analysis of the content of the plasmid DNA, and a polynucleotide represented by a secretory sequence, a fragment encoding human alpha defensin HNP-1 or HNP-2 or HNP-3, codon-optimized for expression in mammalian cells, and a termination sequence. In one embodiment of the invention preproprotein is represented by SEQ ID NO:1 or SEQ ID NO:2 or SEQ ID NO:7 or SEQ ID NO:8. In one embodiment of the invention a polynucleotide is represented by SEQ ID NO:3 or SEQ ID NO:4 or SEQ ID NO:5 or SEQ ID NO:6 or SEQ ID NO:9 or SEQ ID NO:10 or SEQ ID NO:11 or SEQ ID NO: 12.
Also a producer of such plasmid DNA is given based on a bacterial cell (embodiments) and an analgesic agent based on such a plasmid DNA in an effective amount, also containing a pharmaceutically acceptable excipient, for use in mammals, particularly humans (embodiments).
Plasmid DNA is the most economically advantageous to be produced in prokaryotic cells, mainly bacterial cells. In this regard, the plasmid DNA according to the present invention contains elements for maintenance and amplification, mainly in large quantities, in bacterial cells. Such essential elements are a bacterial origin of replication for maintenance in the cell with a medium, preferably a high number of copies per cell, and a reporter gene for selection of a producer strain. Eligible origin of replication is pM1 (der.), ColE1 (der.) and F1, F1 and pUC, but is not limited to them. Eligible reporter gene is a gene of resistance to an antibiotic, e.g., ampicillin, kanamycin mainly, but not limited to them.
Plasmid DNA according to the present invention contains elements for effective functioning in mammalian cells.
Such an element is a promoter with corresponding regulatory sequences of the natural promoters with their regulatory elements (CaM kinase II, CMV, nestin, L7, BDNF, NF, MBP, NSE, p-globin, GFAP, GAP43, tyrosine hydroxylase, subunit 1 of a kainate receptor and subunit B of the glutamate receptor, and others) or synthetic promoters with regulatory sequences, to obtain the desired expression pattern (ratio of length and expression level) of the target gene at the transcriptional level.
Possible regulatory sequences relative to the promoter:
Plasmid DNA according to the present invention contains at least one of the above-mentioned regulatory sequences, depending on the variant of plasmid DNA, based on the choice of promoter and the desired parameters of the expression of the target gene. Based on the existing level of technology, and the known and obvious variants of such elements and their use, plasmid DNA according to the present invention may contain any combinations meeting the mentioned above conditions, in which the synthesis of alpha defensin HNP-1 or HNP-2 or HNP-3 in mammalian cells is performed from the plasmid DNA. When a silencer is used, or insulator, as part of the design, it is possible to regulate the expression of a target gene, the gene of the described human alpha defensin HNP-1 or HNP-2 or HNP-3 (embodiments).
Other regulatory sequences:
Plasmid DNA according to the present invention in one embodiment further comprises such a regulatory element.
Plasmid DNA according to the present invention contains such an important element as a leader mRNA sequence containing Kozak sequence directly before the start codon ATG.
Plasmid DNA also contains a site, preferably sites, different, for cloning of a target gene, for the correct orientation of the target gene in the plasmid DNA, and a site, preferably sites, for primers annealing for its sequencing.
Plasmid DNA also contains a termination sequence containing sequentially a stop codon, the 3′ noncoding region with signal and polyadenylation site, stop codon, with the help of which mRNA remains stable, and the proper termination of transcription and export of mRNA from the nucleus are performed. The terminating sequence is a native sequence, i.e. inherent from the target gene, or other, more powerful, which is represented, for example, by the termination sequence of bovine growth hormone (BGH), but is not limited to such, and in the second embodiment may contain an additional stop codon before the 3′ noncoding region. Based on the existing level of technology, and the known and obvious variants of such elements, plasmid DNA according to the present invention may contain any terminating sequence meeting the above conditions, in the presence of which the synthesis of alpha defensin HNP-1 or HNP-2 or HNP-3 is performed in mammalian cells from the plasmid DNA.
Plasmid DNA also includes a native or a heterologous secretory sequence, codon-optimized for mammals. In one embodiment of the invention it contains, for example, TPA (tissue-type plasminogen activator isoform 1 preproprotein [Homo sapiens], NCBI Reference Sequence: NP_000921.1) secretory sequence, but is not limited to such. The advantage of using TPA secretory sequence is a vast previous clinical experience, and also that its high performance is demonstrated in relation to the expression of the secreted protein from a variety of target genes.
Plasmid DNA also contains a fragment encoding human alpha defensin HNP-1 or HNP-2 or HNP-3, codon-optimized for expression in mammalian cells.
Codon optimization is carried out to increase the expression of the target gene by increasing the efficiency of reading information from mRNA on the ribosomes.
Plasmid DNA can additionally include initial for cDNAs of these genes elements that contribute to the stability of this mRNA, such as a terminating sequence (3′ noncoding region containing the signal and the site of polyadenylation, and also the signal of termination of the transcription—stop codon). Accordingly, in this case analogous elements in the skeleton of the plasmid DNA do not exist or do not function.
Plasmid DNA for the delivery of the gene causing analgesia, combines such properties of DNA vaccines based on a plasmid DNA as a high level of expression of a gene of interest in mammalian cells, and such properties of a vector for a gene therapy, as a lack of immunogenicity and a duration of the gene expression, however, for example, by increasing the stability of mRNA.
Such DNA does not integrate into the genome and is not replicated in mammalian cells.
Suitable vectors for expression in mammalian cells are represented by known to a person averagely skilled in the art and described in the literature [Hartikka J, Sawdey M, Cornefert-Jensen F, Margalith M, Barnhart K, Nolasco M, Vahlsing H L, Meek J, Marquet M, Hobart P, Norman J, Manthorpe M. An improved plasmid DNA expression vector for direct injection into skeletal muscle. Hum Gene Ther. 1996 Jun. 20; 7(10):1205-17 etc.] as well as plasmids, which can be created by a person averagely skilled in the art using the guidelines on the elements of vectors [“Cloning Vectors”, ed. Pouwls et al., Elsevier, Amsterdam—New York-Oxford, 1985, ISBN 0 444 904018, Williams J A, Carnes A E, Hodgson C P. Plasmid DNA vaccine vector design: impact on efficacy, safety and upstream production. Biotechnol Adv. 2009 July-August; 27(4):353-70. doi: 10.1016/j.biotechadv.2009.02.003. Epub 2009 Feb. 20. Review and others]. The preferred plasmid DNA for use in humans are vectors tested on humans containing the above-described elements with corresponding regulatory sequences, feasibly modified to match the stated criteria, which allows to reduce the number of required studies for the registration of a drug. However, the use of other plasmid DNAs containing the required described elements is possible.
The sequence of the elements described in the plasmid DNA is understandable to an expert in this field.
A producer of the plasmid DNA is given based on bacterial cells (based on cells mainly of Escherichia coli, Streptomyces, Bacillus, Pseudomonas, but not limited to such). It is clear to the person skilled in the art that using a plasmid DNA according to the invention and a bacterial cell, e.g., commercial, but it not limited to such, it is possible to create a producer of the plasmid DNA, for example, by standard methods, e.g., transfection, electroporation or particle gun. To reduce the probability of mutations due to methylation of a plasmid DNA it is preferable to use a strain of a microorganism not containing methylase in the genome.
Also an analgesic agent is given based on the described plasmid DNA, in an effective amount, also containing a pharmaceutically acceptable excipient, for use in mammals, particularly in humans. This pharmaceutical composition is to treat, alleviate and/or prevent pain, in particular, acute or chronic pain, disorders of sensitivity.
The authors of this invention conducted laboratory tests confirming the possibility of implementing the described group of inventions. The results obtained are illustrated by examples (1-3) and
1.1. A chemical synthesis of DNA characterized by SEQ ID NO:3—SEQ ID NO:6 and SEQ ID NO:9—SEQ ID NO: 12, optionally flanked by restriction sites, with the addition of a Kozak sequence, was performed. For SEQ ID NO:3 and SEQ ID NO: 10 restriction sites NheI (5′), BamHI (3′) were used, for SEQ ID NO:4 and SEQ ID NO:9 restriction sites SalI (5′), KpnI (3′) were used, for SEQ ID NO:5 and SEQ ID NO:12 restriction sites SalI (5′), BamHI (3′) were used, for SEQ ID NO:6 and SEQ ID NO: 11 restriction sites NheI (5′), ApaI (3′) were used.
1.2. Cloning of the synthesized gene into pVAX1 plasmid (Invitrogen) and pVR1012 (Vical) was performed. Also cloning of the sequence SEQ ID NO: 11 was performed in the vector pcDNA3.1+(Invitrogen) at restriction sites NheI (5′), ApaI (3′). Also a vector pcDNA3.1+ incapable of the expression of neomycin was received, due to the restriction of this vector with NsiI restrictase, in the region of the SV40 promoter (−71 bp). SEQ ID NO:12 was cloned in the resulting vector at restriction sites NheI (5′), ApaI (3′).
1.3. For the ligation reaction 3 μl of the synthesized DNA solution, 1 μl of the prepared vector solution, 5 μl of buffer for ligation ×2 and 1 μl of T4-ligase were taken. The reaction was performed at +20° C. for 2 hours.
Thereafter, the mixture was warmed up at +95° C. for 10 min and purified from salts by dialysis using nitrocellulose filters with pore diameter of 0.025 μm (Millipore, USA). Dialysis was performed against a solution containing 0.5 mM EDTA in 10% glycerol, for 10 min.
The following plasmid DNAs were obtained: pVAX1seq3, pVR1012seq4, pVR1012seq5, pVAX1seq6, pVR1012seq9, pVAX1seq10, pVAX1seq11, pVR1012seq12, pcDNA3.1+seq11, pcDNA3.1+(var)seq12.
1.4. Then the cells of E. coli strain DH10B/R (F-mcrA, Δ(mrr-hsdRMS-mcrBC), φ80dlacZΔM 15, ΔlacX74, deoR, recA1, endA1, araD139, Δ(ara,leu)769, galU, galKλ-, rpsL, nupG) were transformed with the obtained plasmid DNA by the method of electroporation using electroporator MicroPulser (BioRad). This strain does not contain methylase, which helps minimize the possibility of mutations occurrence in DNA, including in gene cloned into the plasmid, sustained in this strain. 1 μl of dialyzed ligase mixture was added to 12 μl of the competent cells and placed between the electrodes of the poration unit and treated with a current pulse.
After transformation, cells were placed in 1 ml of SOC-medium (2% bacto-tripton, 0.5% yeast extract, 10 mM NaCl, 2.5 mM KCl, 10 mM MgCl2, 10 mM MgSO4, 20 mM glucose) and incubated for 40 min at +37° C.
1.5. Identification of clones of E. coli cells containing the plasmid DNA was performed on the selective medium containing LB-agar, 50 μg/ml of kanamycin, or ampicillin (for plasmid DNAs based on pcDNA3.1+).
Plasmid DNA was isolated from the grown clones. Isolation of the plasmid DNA was performed using Wizard Minipreps DNA Purification System (Promega, USA). Purified recombinant plasmid DNA was verified by sequencing.
1.6. Sequencing of the cloned fragments was performed by the method of Sanger using a set of Applied Biosystems BigDye® Terminator (BDT) v3.1 Cycle Sequencing Kit (Applied Biosystems, USA) according to the attached instructions. For the labeling of the reaction products fluorescent dye-labeled ddNTP were used, each ddNTP corresponding to the dye. For sequencing unlabeled plasmid-specific primers were used. A PCR reaction was conducted, then the reaction mixture was purified from free labeled ddNTP using instructions in the kit BigDye X-Terminator Purification Kit (Applied Biosystems, USA), and the sequencing reaction products were separated using capillary sequencer Applied Biosystems 3500/3500xL Genetic Analyzer (Applied Biosystems, USA) and reagent 3500/3500xL Genetic Analyzer Polymer “POP-6™” (Applied Biosystems, USA).
The results of the separation of the reaction products of sequencing were recorded by scanning with laser and the detection of four fluorescent dyes contained in all types of ddNTP.
1.7. Computer analysis of DNA sequences was performed using a personal computer using programs Chromas and BioEdit. The nucleotide sequences of the investigated DNA fragments were aligned with the designed, the identity of the synthesized fragments to the calculated ones was demonstrated. As a result, clones of E. coli cells were selected containing the full sequences of the target genes in the plasmids—the DNA sequences encoding the alpha defensin HNP-1 or HNP-2 or HNP-3.
A colony of E. coli grown on LB-agar in a Petri dish with the addition of kanamycin (or ampicillin), was placed in 10 ml of a selective media. Cells grew over night at +37° C. under constant stirring (250 rpm). The resulting cells were collected by centrifugation at 4000 g. Further isolation and purification of the plasmid DNA was performed using EndoFree Plasmid Mega Kit (Qiagen), which allows to obtain non-pyrogenic DNA. Isolated plasmid DNA was analyzed with electrophoresis in a 0.8% agarose gel, its concentration was measured using fluorometry.
As a control solution water without addition of test preparation was used. 1,950 ml of water and 0.05 ml of test solution (concentration 1 mg/ml) were added into a cell for measuring optical density with a volume of 2 ml, mixed, and the optical density was measured at a wavelength of 260 nm. Determination of the concentration of DNA was performed according to the formula:
C (μg/ml)=40A260K,
where A260—optical density of the preparation measured at a wavelength of 260 nm; K (μg/ml)—for DNA 50 μg/ml (50 μg/ml double-stranded DNA in water); 40—dilution of the test preparation.
In the end it was determined that plasmid DNA pVAX1seq3 was obtained with a concentration of 3.4 mg/ml, pVR1012seq4—3.7 mg/ml, pVR1012seq5—4 mg/ml, pVAX1seq6—3.8 mg/ml, pVR1012seq9—4.1 mg/ml, pVAX1seq10—4 mg/ml, pVAX1seq11—4.3 mg/ml, pVR1012seq12—4.5 mg/ml, pcDNA3.1+seq11 μl—4.4 mg/ml, pcDNA3.1+(var)seq12—4.3 mg/ml. The yield of plasmid DNA ranged from 3.4 mg to 4.5 mg from 1 l of culture medium.
The purity of the obtained plasmid DNA preparation was judged by the ratio of optical density of the preparation measured at a wavelength of 260 nm to the optical density of the preparation measured at a wavelength of 280 nm (A260/A280) and ratio of optical density of the preparation measured at a wavelength of 260 nm to the optical density of the preparation measured at a wavelength of 230 nm (A260/A230). The measurements were performed in aqueous solution, as a reference solution water without addition of the test preparation was used.
For pure preparations of DNA A260/A280>1.80 and A260/A230>1.80 are characteristic. Defined in the experiment values corresponded to the values of the relations A260/A280 and A260/A230 for pure preparations, for all preparations of plasmid DNA received.
A quantitative determination of protein impurities was conducted in the obtained preparations of plasmid DNA pVAX1seq3, pVR1012seq4, pVR1012seq5, pVAX1seq6, pVR1012seq9, pVAX1seq10, pVAX1seq11, pVR1012seq12, pcDNA3.1+seq11, pcDNA3.1+(var)seq12 using the microBCA assay [Smith, P. K., et all, Measurement of protein using bicinchoninic acid. Analyt. Biochem. 150, 76-85 (1985)], measuring the optical density of the obtained colored protein complexes with copper and bicinchoninic acid at a wavelength of 562 nm. The sensitivity of the method microBCA assay is 0.5-20 μg/ml protein. The concentration of total protein in any of the studied preparations of the plasmid DNA did not exceed the norm (from 0.5 to 12 μg/mg of plasmid DNA).
The content of bacterial lipopolysaccharides was also determined in preparations of plasmid DNAs, using a gel-thrombus version of the LAL test, with a sensitivity of >0.25 EU/ml (ToxinSensor, GenScript, USA). A lysate of horseshoe crab Limulus Polyphemus amebocytes served as a LAL-reagent. LAL-reagent specifically reacts with bacterial endotoxins, the result of the enzymatic reaction there is a change in the reaction mixture proportional to the concentration of endotoxin. The results were evaluated according to the presence or absence of a dense thrombus at the bottom of the tube by turning the tube. The gel-thrombus was not formed during the study of a sample diluted 10 times, for preparations of plasmid DNAs pVAX1seq3, pVR1012seq4, pVR1012seq5, pcDNA3.1+(var)seq12 and 5 times for preparations of plasmid DNAs pVAX1seq6, pVR1012seq9, pVAX1seq10, pVAX1seq11, pVR1012seq12, pcDNA3.1+seq11, i.e. at the sensitivity of the method 2.5 EU/ml and 1.25 EU/ml, respectively, which, given the concentration of the plasmid DNA in the sample, confirms a valid indicator of purification from endotoxins.
3.1. Test “Hot plate”
A study of the analgesic activity of plasmid DNAs encoding alpha defensin HNP-1 or HNP-2 or HNP-3 was conducted, using the test “Hot plate” (hot plate).
The test “Hot plate” (Hot plate) was performed to measure the threshold of acute pain sensitivity and the potential analgesic effect of the studied preparations of plasmid DNA [Valdman A. V., Ignatov, Yu. D. Central mechanisms of pain.—L.: Nauka.—1976]. The test is basical for the study of analgesic activity, it is used to identify the analgesic active compounds.
When placed on a hot surface, upon reaching the threshold of pain sensitivity by the animal, motor responses of anxiety are observed: a flick of the paws, licking of paws and jumping. In this test, the latency time since the placement of the animal on a hot surface to the first licking of the paws was considered. This method allows to determine the parameters: the analgesic activity of the tested object, the peak time of analgesia, duration of analgesia.
Mice of line BALB/C were used in the study, females, weighing 15-22 grams, of age 18 weeks. 17 groups of animals were formed in the study including control groups, each group consisted of 3 mice:
1—negative control (saline was injected)
2—pVAX1seq3
3—pVR1012seq4
4—pVR1012seq5
5—pVAX1 seq6
6—pVR1012seq9
7—pVAX1seq10
8—pVAX1seq11
9—pVR1012seq12
10—pcDNA3.1+seq11,
11—pcDNA3.1+(var)seq12
12—analgin (50 mg/kg)
13—morphine hydrochloride (10 mg/kg)
14—pVAX1
15—pVR1012
16—pcDNA3.1+
17—pcDNA3.1+(var)
5 mg/kg of the plasmid DNA were injected.
An appliance Hot plate-meter (Hotplate Analgesia Meter, Columbus Instruments, USA) was used.
Prior to the study test-systems were given 10 minutes to acclimate in the room for the study conduction. Animals were used only once, since the second putting of an animal on a thermostatic plate induced an immediate reaction to the touch of surface. The thermostat temperature was set 55° C. After the injection of the test substance, the animal was gently placed on the heating plate, and at the same time the “start” button on the control panel was pushed. Latency time of licking of the front and rear legs was noted (since the placement of the animal on the surface of the device before the first lick). After that, the “stop” button was pushed, and the animal was removed from the hot surface. Other behavioral responses were ignored. To reduce the likelihood of heat damage of the pads, the maximum time of the experiment did not exceed 60 sec. To determine the peak time of the analgesic action of the preparation, latency time of licking of the front and hind paws was measured in the control group (saline) (point 0) and after 2 h, 12 h, 24 h after preparation administration in the tested groups. The surface of the appliance was wiped with a cloth moistened with disinfectant (0.5% chlorhexidine-digluconate in 70% ethanol), before putting on it the next animal [Methodical recommendations for the students. The pharmaceutical faculty of GOU VPO MMA im. I. M. Sechenov of the Russian Ministry Of Health.—Moscow.—2006].
The analysis of data of determination of the analgesic activity of the preparation was performed. For plasmid DNA which has shown the best result, ED50 was determined, i.e. the dose needed for the demonstration of 50% analgesic activity of the preparation.
The results of the experiment are shown on
In experiment with application of various doses of plasmid DNA which has shown the best result in the previous experiment (pVAX1 seq3), a dose-dependent nature of analgesia in the range from 1 to 10 mg/kg was demonstrated (
3.2. Study of the concentration of beta-endorphin in the serum of mice.
Since the change in the concentration of beta-endorphin in blood plasma can serve a criterion for assessing the effectiveness of anesthesia [Beta-endorphin is a marker of the effectiveness of analgesia for acute pain and chronic pain syndrome in cancer patients/Z. V. Pavlova [and others]//Problems of clinical medicine.—2007.—N1.—S. 36-40.—ISSN 1817-8359], a study of concentration of beta-endorphin in the serum of mice after injection of plasmid DNA was conducted, while introduction of the plasmid DNA encoding HNP-2 or HNP-3 (pVR1012seq4) as example, using the kit ELISA Kit for Beta-Endorphin (bEP) Mus musculus (Mouse) CEA806Mu (Life science Inc.).
The results of the study are shown in
Thus, the possibility of creating different variants of the plasmid DNA encoding HNP-1 or HNP-2 or HNP-3, their obtaining with the use of a bacterial producer, and an analgesic effect of such plasmid DNA are demonstrated, in any of the variants that match the specified criteria, even in a minimal concentration of 1 mg/kg (10 times less than of morphine hydrochloride), and also the safety of using such plasmid DNA is demonstrated: the animals survived, side effects were not observed.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2014145169 | Nov 2014 | RU | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/RU2015/000756 | 11/10/2015 | WO | 00 |
