Patent Application
20200390843
The present invention relates to the formulations for controlled or extended release of certain bioactive compounds, and to the processes for preparation of the same. In particular, the present invention relates to novel sustained release formulations comprising Crocus sativus extract or its active ingredient-enriched fraction for the treatment of chronic inflammatory diseases wherein NLRP3 inflammasome is involved.
The oral route of administration is typically considered the preferred and most patient-convenient means of drug delivery. With many drugs the basic goal of therapy is to achieve a steady-state blood or tissue level that is therapeutically effective and non-toxic for an extended period of time. Sustained release dosage form is an ideal strategy for the drugs with short half-lives and which require repeated dosing. These dosage forms are designed to release a drug at a predetermined rate in order to maintain a constant drug concentration for a specific period of time with minimum side effects.
Crocus sativus L. (Family: Iridaceae), commonly known as saffron or Kesar, is used in Ayurveda and other folk medicines for various purposes, such as an aphrodisiac, antispasmodic and for expectorant effects (Rios J. L. et al., Phytother. Res. 1996, 10, 189-193). Modern pharmacological studies have demonstrated that saffron extracts have anti-nociceptive, anti-inflammatory (Hosseinzadeh, H. et al., BMC Pharmacol. 2002, 15, 7), antitumor (Escribano J. et al., Cancer Lett. 1996, 100, 23), radical scavenger (Abdullaev F. I. et al., Biofactors, 1993, 4, 83), anticonvulsant (Hosseinzadeh H. et al., Arch. Irn. Med., 2002, 5, 44), anti-ischemic (Hosseinzadeh H. et al., 2005, J. Pharm. Pharm. Sci. 8, 387) and anti-Alzheimer (Abe K. et al., Brain Res. 1999, 851, 287; Zhang Y. X. et al. Biol. Pharm. Bull. 1994, 17, 217; Khalili M. et al., Irn. J. Pathol. 2010, 5, 27; Papandreou M. A. et al., J. Agric. Food Chem. 2006, 54, 8762; Khalili M. et al., Irn. J. Pathol. 2010, 5, 27) effects. Recently we have shown that, in in-vivo studies Crocus sativus extract (50 mg/kg/day, added to mice diet) improves the BBB tightness and function that was associated with reduced Aβ load and related pathological changes in 5XFAD mice. Furthermore, Crocus sativus extract upregulated synaptic proteins and reduced neuro-inflammation associated with Aβ pathology in the brains of 5XFAD mice (Batarseh Y. S. et al., ACS Chem Neurosci. 2017, 8, 1756-1766).
Saffron contains more than 150 volatile and aroma-yielding compounds along with carotenoids (including zeaxanthin, lycopene, and various α- and β-carotenes). However, saffron's golden yellow-orange color is primarily the result of α-crocin (also called as crocin-1). It is the diester formed from the disaccharide gentiobiose and the dicarboxylic acid crocetin. When crocetin is esterified with two water-soluble gentiobioses, a water-soluble pigment (known as “crocin”) is obtained. Crocins are esters formed from the conjugation of various sugars (glucose, gentiobiose, triglucose and neapolitanoside) with dicarboxylic acid of crocetin. Furthermore, geometrically crocetin exists in all-trans and 13-cis forms. Thus, total of 16 crocins are reported, all differing via a type of sugar moiety attached and all-trans or 13-cis geometry (Tarantilis P. A. et al., J. Chromatogr. 1995, 699, 107-118; Escribano J. et al., Cancer Lett. 1996, 100, 23-30; Pfister S. et al., J. Agric. Food Chem. 1996, 44, 2612-2615; J. Agric. Food Chem. 2006, 54, 973-979). The chemical structures of crocins are shown in
The present invention describes the preparation of standardized botanical extract of C. sativus stigma, preparation of crocin-1 enriched fraction, and their novel sustained release formulations for delayed or modified release of crocin-1 (an active ingredient) and inhibitory activity against NLRP3 inflammasome. The preclinical characterization of standardized botanical extract of C. sativus stigma has been published (Bharate S S et al., ACS Omega 2018, 3, 9572-9585).
Inflammasomes are high molecular weight complexes that sense and react to injury and infection. The inflammasome is responsible for activation of inflammatory processes (Mariathasan S. et al., Nature 2004, 430, 213), and has been shown to induce cell pyroptosis, a process of programmed cell death distinct from apoptosis. Their activation induces caspase-1 activation and release of interleukin-1β, a pro-inflammatory cytokine involved in both acute and chronic inflammatory responses. There is increasing evidence that inflammasomes, particularly the NLRP3 inflammasome, act as guardians against noninfectious material. Inappropriate activation of the NLRP3 inflammasome contributes to the progression of many non-communicable diseases such as gout (Martinon F. et al, Nature 2006, 440, 237), type-II diabetes (Caroline M O et al., Recent Pat Endocr Metab Immune Drug Discov. 2016, 10, 56-62), rheumatoid arthritis (Choulaki C. et al., Arthritis Res Ther. 2015, 17, 257), chronic obstructive pulmonary diseases (Yang W. et al., Int J ClinExpPathol. 2015, 8, 13209), kidney diseases (Hutton H L et al., Nephrology 2016, 21, 736), myocardial ischemia (Toldo S. et al., Int J Cardiol. 2016, 209, 215), cancer (Wang Y. et al, Oncol Rep. 2016, 35, 2053-2064) and Alzheimer's disease (Heneka, M. T. et al. Nature 2012, 493, 674-678). Therefore, inhibiting the NLRP3 inflammasome may significantly reduce damaging inflammation and is therefore regarded as a therapeutic target for these chronic inflammatory diseases (Baldwin A. G. et al., J. Med. Chem. 2016, 59, 1691-710).
Normally, amyloid-beta load in the brain is low due to clearance by the BBB transporter pumps like P-gp and LRP-1 but with the aging, this clearance mechanism is compromised, consequently fine balance between amyloid-beta production and its clearance from brain get disturbed which ultimately leads to accumulation of large amount of amyloid-beta in brain resulting in neurotoxicity (Vogelgesang, S. et al., Pharmacogenetics 2002, 12, 535-541; Assema V. et al., 2012, Brain, 135, 181-189). As the amyloid-beta load in brain is cleared either by metabolism or efflux from BBB transporter pumps like P-gp and low-density lipoprotein receptor-related protein 1 (LRP1) (Cirrito, J. R., et al., J. Clin. Invest. 2005, 115, 3285-3290); therefore detoxication of amyloid-beta by increasing the P-gp and LRP1 mediated amyloid-beta efflux function could be a novel way of protecting brain from amyloid-beta toxicity.
The objective of this invention to provide novel sustained release formulations of standardized extract of Crocus sativus.
It is also an objective of this invention to provide novel sustained release formulations containing elevated concentrations of at least one of specific markers obtained by means of the process.
It is another objective of this invention to provide the use and method of application of this formulation for treatment of chronic inflammatory diseases wherein NLRP3 inflammasome is involved.
The present invention seeks to provide novel and improved sustained release oral formulations of Crocus sativus for supplying optimum plasma concentrations of the biologically active compounds contained in the plant such as “crocins”. There is thus provided in accordance with a preferred embodiment of the invention an orally-administrable formulation for the controlled release of “crocin-1”.
In one preferred embodiment of the invention, the orally-administrable formulation for the controlled release of active ingredient ‘crocin-1’ comprises granulated hydroalcoholic extract or crocin-enriched fraction and at least one carrier, adjuvant or excipient thereof, and is characterized in that the total in vitro dissolution time of the formulation required for release of 75% of the active ingredient available from the formulation, is between about 4 and about 18 hours, as determined by the U.S.P. basket method at a speed of 50 rpm, and temperature of 37° C.±0.5, using 900 ml of dissolution media.
In one preferred embodiment of the invention, said formulation contains weight ratio of hydroalcoholic extract/fraction of Crocus sativus: polymer(s) is in the range of 30:70 to 70:30.
In another preferred embodiment of the invention, the formulation is characterized in that it contains from 20 to 80% w/w hydroalcoholic extract or crocin-1 enriched fraction.
In another preferred embodiment of the invention, the formulation is in the form selected from the group consisting of a matrix tablet or a hard gelatin two-piece capsule filled with polymeric granules or microparticles of granulated extract.
In another preferred embodiment of the invention, the formulation comprises granulated extracts mixed or coated with an excipients or polymers selected from the group consisting of hydroxypropyl methylcellulose K4M (HPMC-K4M), hydroxypropyl methylcellulose K15M (HPMC-K15M), ethyl cellulose 10-100 cps, hydroxy propyl methyl cellulose phthalate (HPMCP), hydroxy propyl methyl phthalate cellulose acetate succinate (HPMPCAS), cellulose acetate phthalate (CAP), eudragit S100, eudragit L100, eudragit RS 100, eudragitRL 100, polyethylene oxide, xanthan gum, chitosan, gelatin, sodium alginate, magnesium stearate, silicon dioxide, dicalcium phosphate, microcrystalline cellulose, lactose, starch and talc.
In another preferred embodiment of the invention, the binder is selected from group consisting of polyvinylpyrrolidone K30 and polyvinylpyrrolidone K15 and binder solution is prepared by 5-10% w/v in isopropyl alcohol, methanol, ethanol or propanol.
In another preferred embodiment of the invention, said extract contains at least 15% w/w of active ingredient trans-crocetin-di-(β-D-gentiobiosyl)ester (crocin-1).
In another preferred embodiment of the invention, said fraction contains at least 30% w/w of active ingredient trans-crocetin-di-(β-D-gentiobiosyl)ester (crocin-1).
The invention also comprises a process for the preparation of an orally-administrable formulation for the controlled release of a granulated extract. The steps for preparation of said formulation comprising granulated extract and at least one carrier, comprises:
In another aspect of the present invention, said formulation comprises extract of Crocus sativus in an amount of 30-70% by weight of the formulation and at least 4.5%of active ingredient trans-crocetin di-(β-D-gentiobiosyl)ester (crocin-1).
In another aspect of the present invention, in the comparative pharmacokinetic study conducted in SD rats, the sustained release formulation (IIIM-141-SR) displayed 3.3-fold enhancement in the AUC of the crocetin (a bioactive metabolite, formed via enzymatic hydrolysis in the plasma/GIT) in comparison to the plain extract.
In another aspect of the present invention, the ratio of crocin: crocetin in the plasma of rats was enhanced from 1:4 to 1:9 in SR formulation (IIIM-141-SR).
In another aspect of the present invention, the prolonged release of the bioactive constituent (a hydrolyzed metabolite crocetin) was observed up to 24 hrs in the rat plasma in SR formulation (IIIM-141-SR) in comparison to the plain extract.
In another aspect of the present invention, a method for enrichment of one of the active constituent is provided.
In one more embodiment of the invention, the standardization of the C. sativus extract is provided to identify and quantify amount of specified marker in the standardized extract of C. sativus by HPLC.
In another embodiment of the invention, standardized extract of C. sativus (IIIM-141-A002) displayed significant inhibition of NLRP3 inflammasome in human monocytic THP-1 cells.
In one particular aspect of the present invention, an extract of C. sativus is provided, which comprises active components for NLRP3 inhibition, and related manifestations and disorders with a pharmaceutically acceptable carrier, and methods of using the same. Accordingly, the present invention is directed generally to the sustained release formulations of standardized extracts or crocin-1 enriched fraction of C. sativus for treatment of chronic inflammatory diseases wherein NLRP3 inflammasome is involved.
In another aspect of the invention, chronic inflammatory diseases comprises gout, type II diabetes, rheumatoid arthritis, chronic obstructive pulmonary diseases, kidney diseases, myocardial ischemia, cancer and Alzheimer's disease.
In one more embodiment of the invention, standardized extract of C. sativus display significant increase in P-gp efflux function (as determined by Rh123) and increase in P-gp protein expression in P-gp endogenously expressing adenocarcinoma cells (LS-180 cells) in-vitro.
AUC, area under the curve; aCSF, artificial cerebrospinal fluid; CAP, cellulose acetate phthalate; HBSS, Hank's buffered salt solution; HPMCP, hydroxy propyl methyl cellulose phthalate; HPMC-K15M, hydroxypropyl methyl cellulose-K15M; LS-180 is a colon adenocarcinoma cell line; LRP1, low-density lipoprotein receptor-related protein 1; NLRP3, NOD-like receptor (NLR) subfamily; PVP-K30, polyvinylpyrrolidone K 30; P-gp, p-glycoprotein; Rh123, rhodamine 123; SAM, Swiss Albino mice; STZ, streptozotocin; THP-1 is a human monocytic cell line; TBST is mixture of tris-buffered saline (TBS) and Tween 20; SD rat, Sprague Dawley rat.
The present invention provides novel sustained release formulations of hydroalcoholic extract and crocin-1 enriched fraction of Crocus sativus stigma for treatment of chronic inflammatory diseases involving NLRP3 inflammasome. More specifically, this invention is further directed to methods of preparation of hydroalcoholic extract or active ingredient enriched fraction from the dried stigmas of Crocus sativus using ethanol and water in ratio of 1:1. The hydroalcoholic extract (IIIM-141-A002) and crocin-enriched fraction (IIIM-141-CEF) are standardized for the content of major active constituent “crocin-1”. The hydroalcoholic extract and crocin-enriched fraction contain 33.12±3.26% and 55.19±1.82% of crocin-1, as determined by HPLC analysis.
Particularly, this invention provides the method for preparation of novel sustained release formulations wherein the extract is wet-granulated using excipients, biodegradable polymers and/or non-biodegradable polymers alone or in combination, and the said granules are either filled into a capsule or compressed into a tablet. The said formulation comprising a granulated extract of Crocus sativus with polymers results in sustained release of the extract in the gastrointestinal tract.
Moreover, this invention provides formulations wherein the total in-vitro dissolution time of said formulations required for release of 60-80% of the active ingredient “crocin-1” is between 8 to 16 hours, as determined by the U.S.P. dissolution apparatus by basket method at a speed of 50 rpm, and temperature of 37° C.±0.5, using 900 ml of dissolution media. The sustained release of the bioactive constituent was observed in the rat pharmacokinetic study; which validated the in-vitro dissolution results. After oral administration of crocin-enriched fraction (IIIM-141-CEF) as well as IIIM-141-SR formulation in rats, it was observed that crocin, the major constituent of Crocus sativus extract, gets metabolized to “crocetin”, which is the bioactive metabolite. The crocin-enriched fraction (IIIM-141-CEF) and its SR formulation, when administered orally at equivalent dose (a dose equivalent to 45 mg/kg of crocin), the significantly higher AUC for “crocetin” was observed in case of SR formulation in comparison to the plain extract. This result indicated that SR formulation controls the release of extract, leading to the release of bioactive constituent for prolonged time. As an overall effect of this, the higher amount of crocetin is available in the blood circulation, which ultimately results in improved therapeutic effect.
The significant inhibition of NLRP3 inflammasome in human monocytic THP-1 cells by IIIM-141-A002 is depicted in
The spectrums of conditions for which the inventive extract can be used for inflammatory conditions where NLRP3 inflammasome is involved, includes, but not limited to gout, type II diabetes, rheumatoid arthritis, chronic obstructive pulmonary diseases, kidney diseases, myocardial ischemia, cancer, Alzheimer's disease.
The following examples, which include preferred embodiments, will serve to illustrate the practice of this invention, it being understood that the particulars shown are by way of example and for purpose of illustrative discussion of preferred embodiments of the invention
Following examples are given by way of illustration and should not construe to limit the scope of invention.
The authentic plant material of Crocus sativus (stigma) was purchased from local market of Srinagar (Jammu and Kashmir State, India). The plant material was taxonomically characterized, and a voucher specimen was deposited in the Janaki Animal Herbarium at the CSIR-IIIM, Jammu. Driedmaterial was extracted with water: ethanol (1:1) mixture and then freeze dried.
The steps include:
The active ingredient [trans-crocetin di-(β-D-gentiobiosyl) ester] (crocin-1) enriched extract was prepared using following procedure:
The hydroalcoholic extract is primarily a mixture of crocins, which are crocetin glycosides. The HPLC/LCMS analysis indicated that amongst the total 16 crocetin-esters (crocins) reported (chemical structures are shown in
HPLC analysis was performed on the Shimadzu HPLC system connected to a PDA detector, and C8 (Intersil, 25 cm×4.6 mm, 5μ) column. Mobile phase consisted of acetonitrile (A) and 0.1% formic acid in water (B). The gradient system comprised of 70% B (0.01 min), 70% B (2 min), 30% B (7 min), 30% B (15 min), 70% B (20 min), 70% B (25 min) at a flow rate of 1 ml/min.
The hydroalcoholic extract was found to contain 33.11±3.25 (average of six different experiments) of trans-4-GG-crocin. Thus, the % content of trans-4-GG-crocin in Crocus sativus (stigma) dried material was found to be 15.6%. The trans-4-GG-crocin enriched fraction (IIIM-141-CEF) was found to contain 55.19±1.82% of trans-4-GG-crocin. The chemical structures of all crocins are provided in
The hydroalcoholic extract (IIIM-141-A002) or crocin-1 enriched fraction (IIIM-141-CEF) and excipient(s) were weighed accurately and mixed thoroughly using mortor and pestle. This mixture was kneeded using 10% PVP-K30 solution in isopropanol (as a binder) to form a dough. This dough was then passed through sieve #10. The obtained granules were dried in vacuum dessicator at room temperature. The formulations were assayed for crocin-1 content using HPLC method as mentioned in example 1. Based on the results of assay, formulation equivalent to 50 mg of crocin-1 was filled into the hard gelatin capsules of size ‘0’. These capsules were analyzed for in-vitro dissolution profile.
Some of the composition of sustained release formulations are provided in Table 1.
aA 10% PVP-K30 solution in isopropanol was added as a binder in each formulation to form a dough.
The dissolution profile of plain hydroalcoholic extractor crocin-1 enriched fraction and their sustained release formulations was studied using USP dissolution apparatus as per the protocol given in USP 2011 (The United States Pharmacopoeial Convention. 2011, Pages 1-8). Lab-India Dissolution Tester (Model: DS 8000; apparatus 1—Basket Apparatus) was used for this study. Various parameters are: RPM=50; Temp.=37° C.±0.5; Volume of dissolution medium=900 ml; Dissolution medium=(A) Hydrochloric acid buffer (pH 1.2) for first 2 h, (B) Phosphate buffer pH 6.8; Sampling time points (h)=0.5, 1, 2, 4, 8, 12, 16, 20 and 24.
The percent release of trans-crocetin di-(β-D-gentiobiosyl) ester (“crocin-1”) from developed formulations was determined by HPLC analysis (
The dissolution profiles of formulations of hydroalcoholic extract of Crocus sativus are shown in
The summarized overview of best formulations with their T10%, T50% and T75% values are shown in Table 2. The release half-life (T50%) for crocin-1 in plain extract and fraction is <0.5 hr, whereas it is 8 and 12 hrs. in novel sustained release formulations CSHA-14 and CSE-2. The T75% (time taken to release 75% of drug from the formulation) for crocin-1 in plain extract and fraction is <0.5 hr, whereas it is 20 and 24 hrs. in novel sustained release formulations CSHA-14 and CSE-2. This is indicative of the delayed release of crocin-1 from novel formulations.
For comparative oral pharmacokinetic study of plain extract (IIIM-141-A002) and SR formulation (filled in 9e1 capsules), the dose equivalent to 45 mg/kg of crocin was administered in SD rats in both these groups. Blood samples were collected (n=3/time point) at 0.083 (IV only), 0.25, 0.5, 1, 2, 4, 8 and 24 h, post-dose. At each time point about 200 μL of blood was collected by jugular vein into a labeled microfuge tube containing 200 mM K2EDTA solution (20 μL per mL of blood) and equivalent volume of heparinized saline was replaced following sample collection. The blood samples were processed to obtain the plasma samples within 30 min of scheduled sampling time. All plasma samples were stored below −60° C. until bioanalysis. The plasma samples were analyzed for crocin and crocetin content using a fit-for purpose LC-MS/MS method with a lower limit of quantification (LLOQ) of 9.95 ng/mL. The pharmacokinetic parameters of crocin and crocetin were calculated using the non-compartmental analysis tool of validated Phoenix® WinNonlin® software (version 6.3).
The PK parameters of crocin-1 and crocetin after administration of crocin-1 enriched fraction (IIIM-141-CEF) and its sustained release formulation (IIIM-141-SR) at a dose equivalent to 45 mg/kg of crocin-1 in SD rats are shown in Table 3. The time-plasma concentration curve of extract and formulation is depicted in
Table 3. PK parameters of crocin-1 and crocetin after administration of crocin-1 enriched fraction (IIIM-141-CEF) and its sustained release formulation (IIIM-141-SR) at a dose equivalent to 45 mg/kg of crocin-1 in SD rats.
IIIM-141-A002 was screened for its ability to induce P-gp using rhodamine123 (Rh123) cell exclusion method. In this method, P-gp function was evaluated in terms of rhodamine 123 (Rh123) accumulations and efflux. Briefly, the protocol used is as follows: Colorectal LS-180 cells [obtained from ECACC (European Collection of Cell Cultures) catalogue number: 87021202; passage number 52] were seeded at a density of 2×104 per well of 96 well plate and were allowed to grow for next 24 h. Cells were further incubated with the test samples, and were diluted to the final desired series of concentrations and rifampicin (standard) to a final concentration of 10 μM in complete media for 48 h. The final concentration of DMSO was kept at 0.1%. Test sample and standard rifampicin were removed and cells were incubated with HBSS solution for 40 minutes before further incubation with HBSS solution (containing 10 μM of Rh123 as a P-gp substrate) for 90 minutes. At the end of Rh123 treatment cells were washed four times with cold PBS followed by cell lysis for 1 h by using 200 μl of lysis buffer (0.1% Triton X-100 and 0.2 N NaOH). A total of 100 μl of lysate was used for reading fluorescence of Rh123 at 485 nm/529 nm Samples were normalized by dividing fluorescence of each sample with total protein present in the lysate.
IIIM-141-A002 treatment in LS-180 colon cancer cells at various concentrations ranging from 6.25 μg/ml to 100 μg/ml led to significant increase in the efflux of substrate rhodamine 123 dye as determined by decrease (by 16-40%) in intracellular % Rh123 levels (
The protein lysates were prepared and total protein content in lysate were measured employing Bio-Rad protein assay kit using bovine serum albumin as standard. Proteins aliquots (70 μg) were resolved on SDS-PAGE and then electro transferred to PVDF membrane overnight at 4° C. at 30V. Non-specific binding was blocked by incubation with 5% non-fat milk in Tris-buffered saline containing 0.1% Tween-20 (TBST) for 1 h at room temperature. The blots were probed with P-gp antibody for 4 h and washed three times with TBST. Blot was then incubated with horseradish peroxidase conjugated anti-mouse secondary antibody for 1 h, washed again three times with TBST and signals detected using ECL plus chemiluminescence's kit on BioRadChemiDoc XRS system.
Western-blot results clearly indicate that IIIM-141-A002 induces P-gp expression by 3-8 fold in LS-180 colon cancer cells at concentrations ranging from 12.5-100 μg/ml, respectively as shown in
THP-1 cells were differentiated with phorbol-12-myristate-13-acetate (PMA) (20 ng/ml) for 24 h. The media was changed after 24 h followed by rest of two days in complete RPMI containing 10% heat inactivated FCS. Cells were primed with LPS (1 μg/ml) for 4 h followed by pre-treatment with different concentration of hydroalcohlic extract of Crocus sativus for 30 min. Then, cells were stimulated with nigericin, 10 μM for 1 h. Supernatant was collected and stored at −20° C. for ELISA of IL-1β. Secretion of IL-1β with nigericin was measured by BD OptEIA for IL-1beta (human) and was considered as readout for NLRP3 activation.
IIIM-141-A002 showed strong inhibition of NLRP3 inflammasome at the low concentration of 25 μg/ml. Results are shown in
Animals were randomized into 4 groups based on body weight, each group with n=5-7. Artificial cerebrospinal fluid (a CSF—147 mM NaCl, 2.9 mMKCl, 1.6 mM MgCl2, 1.7 mM CaCl2, 2.2mM dextrose) was injected to group 1 or STZ (3 mg/kg) to group 2-5 animals through intra-cerebroventricular (ICV) route on day 1 and 3. On 15th-18th day, vehicle was administered to group 1-2, test compound IIIM-141-002 at a dose of 50 and 100 mg/kg, p.o. to group 3 and 4 animals respectively. Rats were subjected to MWM test 30 min after dosing, 4 trials were conducted each day for 4 days i.e. from 15th to 18th day. If animal failed to locate the hidden platform in stipulated time, they were gently pushed to the hidden platform and kept on platform for 20 seconds. Time (seconds) to locate the hidden platform was recorded as escape latency (latency time).Escape latency were recorded for retention session i.e. from day 16-18. The difference (% change) in escape latency was compared with aCSF.
There was significant increase in latency time to locate the hidden platform in STZ treated rats as compared with aCSF treated rats suggesting memory impairment. A significant increase in latency time was observed in ICV-STZ treated rats at day 3 & 4 indicating memory deficit. Further, treatment with test compound (IIIM-141-002) decreased the STZ induced memory impairment in rats as demonstrated by reduction in latency time at dose of 100 mg/kg p.o. for 4 days. Results are shown in
Animals were randomized to their body weight (n=6-8). All animals were then habituated to experimental apparatus (Passive avoidance instrument of make—UGO Basile Biological Research Apparatus Italy) prior to the experiment. For habituation, animals were placed gently in the light compartment of the apparatus. After 5 seconds guillotine door was opened and animal allowed entering the dark compartment without giving the shock. Animals that took more than 100 seconds to enter the dark room were eliminated from the experiments. For acquisition trial the animals were placed in light compartment and allowed to enter the dark compartment through guillotine door. As soon as the animal entered to the dark compartment, door was closed and animal was delivered a foot shock (0.5 mA current) immediately for the duration of 5 seconds. Animals were then removed from apparatus after 20 seconds and placed temporarily in its home cage. Repeated the same procedure (keeping the gap between acquisition trials to 5 minutes) till the animal remained in the light compartment for consecutive 120 seconds. Retention was recorded at day 2 without shock in dark chamber. Increase in transfer latency time from light to dark chamber indicated learning in animals. Rivastigmine was used as positive control in this study. The data were acquired as transfer latency (in sec) i.e. time taken by each mice to move from light compartment to dark compartment (Table 2). Percentage (%) change in transfer latency as compared with control on retention trial was calculated. The scopolamine group was compared with control while test/standard groups were compared with scopolamine treated animals. For statistical analysis, one way ANOVA followed by Tukey test was used.
This study suggests that scopolamine administration results in memory impairment in mice as demonstrated by significant reduction in transfer latency as compared with control in retention trial. Administration of test compound IIIM-141-002 at 100 mpk for 7 day significantly recovered the memory as shown by increase in transfer latency as compared with scopolamine treated mice. Positive control rivastigmine at a dose of 2 mg/kg resulted in a significant reduction in latency time (
The main advantages of the present invention are:
| Number | Date | Country | Kind |
|---|---|---|---|
| 201711036684 | Oct 2017 | IN | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IN2018/050629 | 10/18/2018 | WO | 00 |
