Patent Application
20080267936
The invention relates generally to biotechnology and medicine.
Injury is the fifth leading cause of death worldwide and will become the second leading cause by 2020. It is already the leading cause of death in individuals aged 5 to 45 years. Vehicular injury, self-inflicted injury, interpersonal violence (including war), work-related injury, falls, burns, and environmental disasters all contribute their share.
Primary prevention is the most effective way to limit injury. The importance of education, engineering controls, and the rule of law in prevention of injury cannot be overemphasized. Almost as many individuals die of vehicular injury in Egypt as in the U.S., but Egypt has one-quarter the population, and one-tenth the number of vehicles. Nevertheless, the majority of injuries in both countries are preventable.
Secondary prevention, the application of acute care to prevent death and disability following injury, is also highly effective. The cost of trauma care is low per quality-adjusted life year saved compared with treatments in other common disease categories, such as cardiovascular illness, stroke, or cancer interventional therapy. This care is best provided in regional centers. The largest Level 1 trauma centers typically see more than 5000 direct admissions each year and are staffed around the clock with trauma surgeons, neurosurgeons, orthopedists, anesthesiologists, and a complete array of support staff. The work of these centers in patient care, medical education, and developing new knowledge is driving an international revolution in the quality of injury care.
Every year, one in seven Americans is significantly injured. The diagnosis of such injuries (including trauma-hemorrhage and hemorrhagic shock) is well within the skill of the art of a health care professional (e.g., medical doctor, nurse, EMT, etc.), and typically involves a physical examination of the injured subject. Two-thirds of those significantly injured, or one person in ten of the U.S. population, seek medical care for that injury, and one out of every 100 Americans is admitted to a hospital for injury care each year. About one in every ten patients admitted for injury, or one out of every 1000 Americans, receives blood products in the course of injury care. These individuals receive 10% to 15% of all of the blood transfused in the U.S.
Severe hemorrhage and hemorrhagic shock are common causes of morbidity and mortality in critically ill patients in intensive care. Patients in shock have impaired macro- and microcirculation in various tissue beds. Impaired splancnic perfusion plays an important role in the development of multiple organ dysfunction owing to enhanced bacterial translocation from the gut and activation of an exacerbated inflammatory cascade. Decreased splancnic perfusion also leads to the low blood supply to the downstream organs, such as the liver, leading to hepatic dysfunction, which also contributes to multiple organ failure after shock.
About 156,000 people die of injury each year in the U.S., and 93,000 of those fatalities involve physical trauma. Half of these individuals die before they reach the hospital. Among those who reach the hospital alive and who will die during that hospital admission, 80% die within the first 24 hours after admission. The most frequent causes of death of patients who die in the field or in the hospital are profound neurologic injury and uncontrolled hemorrhage.
Control of hemorrhage is a critical aspect of trauma care. In the field, bandages, direct pressure, and tourniquets control superficial and extremity hemorrhage. In the hospital, diagnostic imaging and surgical exploration allow the rapid identification of most other sites of bleeding. However, identification of sites of injury does not always allow immediate control of hemorrhage. Injuries such as deep hepatic lacerations and pelvic fractures with disruption of the pelvic venous plexus frequently require packing, and control of bleeding is obtained only slowly. These injuries can result in extensive and prolonged bleeding even in the hospital.
Patterns of blood use following traumatic injury are determined by the patterns of injury, the speed of transport to surgical care, and the availability of resources at the surgical center. At the University of Maryland R. Adams Cowley Shock Trauma Center in Baltimore in calendar year 2000, 91% of 5649 patients admitted directly from the scene of injury received no blood products. About two-thirds of the remainder, 332 patients, received 10 U of red blood cells (RBCs) or less. However, 75% of the RBCs administered were given to the 146 patients who received more than 10 U and 50% of all the RBCs used were administered to 68 patients who received more than 20 U of RBCs each. Thus, a select group of trauma patients receive transfusion, and it is these patients who are changing the thinking about blood use and resuscitation and towards treatment.
Criteria decisive for the decision to resuscitate or transfuse a patient suspected undergoing trauma-hemorrhage are diverse and complex (see, for example, Critical Care, Management of Bleeding Following Major Trauma: a European Guideline, Posted Apr. 2, 2007, Donat R. Spahn, Vladimir Cerny, Timothy J. Coats, Jacques Duranteau, Enrique Fernandez-Mondéjar, Giovanni Gordini, Philip F. Stahel, Beverley J. Hunt, Radko Komadina, Edmund Neugebauer, Yves Ozier, Louis Riddez, Arthur Schultz, Jean-Louis Vincent, Rolf Rossaint, WorldWideWeb.medscape.com/viewarticle/554058—1 and on), however, at a certain moment, it is decided whether and how to resuscitate by providing such patients with RBCs or plasma, platelets or other blood products.
Herein, it is determined whether administration of short oligopeptides has any effect on deleterious immune functional parameters after trauma-hemorrhage.
Disclosed herein are methods and associated means for treating a subject (e.g., a mammal such as a human), experiencing, diagnosed as experiencing, or thought to be at risk for experiencing hemorrhagic shock. Such methods include administering to the subject in a medically or pharmaceutically acceptable manner, a short oligopeptide such as AQGV (SEQ ID NO:1) and/or LQGV (SEQ ID NO:2). Therewith, provided are methods of treating a subject experiencing hemorrhagic shock, such methods comprising treating that subject with a short oligopeptide, and preferably comprising first diagnosing the subject to determine whether or not the subject is experiencing hemorrhagic shock and, if the subject is determined to be experiencing or at risk for experiencing hemorrhagic shock, administering to the subject an oligopeptide or pharmaceutically acceptable salt or ester of the oligopeptide, the oligopeptide constituting a means for treating hemorrhagic shock in the subject.
Therewith, provided are methods for treating a subject suffering from or believed to be suffering from trauma-hemorrhage, more in particular, hemorrhagic shock, the method comprising providing the subject with at least one isolated or synthetic peptide, or functional analogue or derivative thereof, of smaller than 30 amino acids, the peptide preferably identified by testing at least one isolated or synthetic peptide of smaller than 30 amino acids in an experimental animal model of trauma-hemorrhage and demonstrating that administration of the test peptide after induction of trauma-hemorrhage reduces the plasma level of at least one pro-inflammatory cytokine (for example, TNF-α or IL-6 as provided herein) in an animal subjected to trauma-hemorrhage when compared with an animal subjected to trauma-hemorrhage that has not been provided with a test peptide. It is preferred that the peptide or test peptide is smaller than 15 amino acids, but more preferred that it is smaller than seven amino acids; for example, wherein the peptide or test peptide consists of two to six amino acids, more preferred wherein the peptide consists of three to five amino acids, and most preferred wherein the peptide consists of four amino acids.
In certain embodiments, the peptide consists of AQGV (SEQ ID NO:1), LQGV (SEQ ID NO:2), or LAGV (SEQ ID NO:3). Treatment with mixtures of peptides is also provided. Preferred mixtures comprise at least one peptide selected from the group of AQGV (SEQ ID NO:1), LQGV (SEQ ID NO:2), or LAGV (SEQ ID NO:3), and another peptide. A preferred other peptide is selected from those capable of reducing pro-inflammatory cytokine levels in an animal model of trauma-hemorrhage or hemorrhagic shock, such as one provided herein.
In certain embodiments, the treatment of trauma-hemorrhage or hemorrhagic shock also comprises providing (resuscitating or transfusing) the subject with blood or blood products, such as red blood cells (RBCs), platelets, plasma, or combinations thereof.
The invention also provides use of at least one isolated or synthetic peptide, or functional analogue or derivative thereof, of smaller than 30 amino acids for the production of a pharmaceutical composition for the treatment of a subject suffering from or believed to be suffering from trauma-hemorrhage or hemorrhagic shock, the peptide preferably identified by testing at least one isolated or synthetic peptide of smaller than 30 amino acids in an experimental animal model of trauma-hemorrhage and demonstrating that administration of the test peptide after induction of trauma-hemorrhage reduces the plasma level of at least one pro-inflammatory cytokine (for example, TNF-α or IL-6 as provided herein) in an animal subjected to trauma-hemorrhage when compared with an animal subjected to trauma-hemorrhage that has not been provided with a test peptide. It is preferred that the peptide or test peptide is smaller than 15 amino acids, more preferred that is smaller than seven amino acids, for example, wherein it consists of two to six amino acids, even more preferred wherein the peptide consists of three to five amino acids, and most preferred wherein the peptide consists of four amino acids.
In certain embodiments, the treatment of trauma-hemorrhage also comprises providing the subject with blood or blood products, such as red blood cells (RBCs), platelets, plasma, or combinations thereof.
Also provided are methods for identifying a peptide, or functional analogue or derivative thereof, for use in the production of a pharmaceutical composition for the treatment of a subject suffering from or believed to be suffering from trauma-hemorrhage comprising testing at least one isolated or synthetic peptide of smaller than 30 amino acids in an experimental animal model of trauma-hemorrhage and demonstrating that administration of the test peptide after induction of trauma-hemorrhage reduces the plasma level of at least one pro-inflammatory cytokine in an animal subjected to trauma-hemorrhage when compared with an animal subjected to trauma-hemorrhage that has not been provided with a test peptide. The test peptide may be tested in a method according to the invention wherein the animal subjected to trauma-hemorrhage is also provided with blood or blood products, such as red blood cells (RBCs), platelets, plasma, or combinations thereof.
Also provided is selecting the test peptide capable of reducing the desired pro-inflammatory cytokine levels for use in the production of a pharmaceutical composition, in particular, wherein the pharmaceutical composition is produced for the treatment of a subject suffering from or believed to be suffering from trauma-hemorrhage hemorrhagic shock.
In hemorrhagic shock, there is massive blood loss, which cannot be compensated by the body without treatment. The primary treatment of hemorrhagic shock is to control bleeding and restore intravascular volume to improve tissue perfusion. This treatment induces an inflammatory response, which may culminate into a severe inflammatory response and finally multiple organ dysfunction syndrome (MODS).[1, 2, 3] In addition, approximately 40% of patients develop sepsis as a result of trauma-hemorrhage.[3] Sepsis and MODS are the leading causes of death in critically ill patients on the intensive care unit all over the world with mortality rates of about 50%.[4, 5]
The severe inflammatory response due to trauma-hemorrhage is characterized by increased expression of adhesion molecules, such as intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), on sinusoidal endothelial cells and hepatocytes. Furthermore, increased levels of pro-inflammatory cytokines are found systemically and locally in liver, lungs and intestine.[6, 7, 8, 9] The pro-inflammatory cytokines produced are, in particular, tumor necrosis factor alpha (TNF-α), interleukin (IL)-1β and IL-6.[10, 11, 12] These cytokines affect organ integrity/function directly, but also indirectly through secondary mediators, such as nitric oxide, thromboxanes, leukotrienes, platelet-activating factor, prostaglandins, and complement.[13, 14] TNF-α also causes the release of tissue-factor by endothelial cells leading to fibrin deposition and disseminated intravascular coagulation.[15, 16] Cells within the liver, mainly Kupffer cells, but also hepatocytes and sinusoidal endothelial cells, are considered as the main producers of these pro-inflammatory cytokines during hemorrhagic shock.[17]
A fine balance between vasodilators and vasoconstrictors maintains splancnic perfusion. Increased systemic production of vasoconstrictors such as epinephrine, angiotensin II, endothelin, and thromboxane A2 has been observed in experimental models of trauma-hemorrhage and sepsis. These vasoconstrictors not only contribute to the increased total peripheral resistance but also act on the splancnic vessels and reduce their perfusion rate. The reduced production of vasodilators or the attenuated response of the splancnic vessel to the vasodilators (endothelial dysfunction) is also observed after severe hemorrhagic shock. Both of these factors contribute to the circulatory disturbance. In addition, these effects induce intestinal hypoxia, reduce nutrient supply, increase production of oxygen free radicals, and increase neutrophil accumulation, leading to damage of the intestinal mucosal barrier and thereby resulting in increased bacterial translocation.
During the last decade, researchers have focused on the modulation of the systemic inflammatory responses with therapeutic agents aiming at neutralizing the activity of cytokines, especially TNF-α.[18] Other researchers used therapeutic agents aiming at the inhibition of TNF-α production.[19] However, most of these therapeutic agents must be administered before the onset of hemorrhagic shock to achieve a therapeutic effect.[19] Clearly, this is almost impossible in a clinical trauma-hemorrhage setting. Therefore, therapies initiated after the onset of severe trauma-hemorrhage and aiming at reducing the production of pro-inflammatory cytokine are more relevant to prevent the events leading to MODS.
During pregnancy, the maternal immune system tolerates the fetus by reducing the cell-mediated immune response while retaining normal humoral immunity.[20] Also, clinical symptoms of cell-mediated autoimmune diseases regress in many patients during pregnancy.[20] The hormone human chorionic gonadotropin (hCG) is mainly secreted by placental syncytiocytotrophoblasts during pregnancy and has been shown to be immunoregulatory.[21, 22, 23] The β-subunit of hCG is degraded by specific proteolytic enzymes.[24] This can lead to the release of several oligopeptides consisting of four to seven amino acids which, because of their role in regulation of physiological processes, are considered regulatory.[25] We successfully demonstrated that synthetic oligopeptides can inhibit the acute inflammatory response, disease severity, and mortality in high-dose lipopolysaccharide-induced systemic inflammatory response syndrome.[26] Considering these powerful regulating effects of synthetic oligopeptides on inflammation, we hypothesized that the administration of such regulatory oligopeptides after severe trauma-hemorrhage could inhibit the massive inflammatory response associated with this condition. To this end, we used LQGV (SEQ ID NO:2), which is part of the primary structure of loop two of the β-subunit of hCG, and two alanine replacement variants, namely AQGV (SEQ ID NO:1), and LAGV (SEQ ID NO:3).
Herein, it is demonstrated that LQGV (SEQ ID NO:2), AQGV (SEQ ID NO:1), and LAGV (SEQ ID NO:3), administrated after the induction of hemorrhagic shock in rats, significantly reduced TNF-α and IL-6 plasma levels, which is associated with reduced TNF-α and IL-6 mRNA transcript levels in the liver. This indicates that LQGV (SEQ ID NO:2), AQGV (SEQ ID NO:1), and LAGV (SEQ ID NO:3) have therapeutic potential with beneficial effects on systemic inflammation, thereby reducing organ integrity/function, which is associated with severe hemorrhagic shock.
U.S. Pat. No. 5,380,668 to Herron (Jan. 10, 1995), the contents of the entirety of which are incorporated by this reference, discloses, among other things, various compounds having the antigenic binding activity of hCG. Herron further discloses means and methods for making oligopeptides.
The compounds according to the general formula may be prepared in a manner conventional for such compounds. To that end, suitably N-alpha-protected (and side-chain-protected if reactive side-chains are present) amino acid derivatives or peptides are activated and coupled to suitably carboxyl-protected amino acid or peptide derivatives either in solution or on a solid support. Protection of the alpha-amino functions generally takes place by urethane functions, such as the acid-labile tertiary-butyloxycarbonyl group (“Boc”), benzyloxycarbonyl (“Z”) group and substituted analogs or the base-labile 9-fluoremyl-methyloxycarbonyl (“Fmoc”) group. The Z group can also be removed by catalytic hydrogenation. Other suitable protecting groups include the Nps, Bmv, Bpoc, Aloc, MSC, etc. A good overview of amino protecting groups is given in The Peptides, Analysis, Synthesis, Biology, Vol. 3, E. Gross and J. Meienhofer, eds. (Academic Press, New York, 1981). Protection of carboxyl groups can take place by ester formation, for example, base-labile esters like methyl or ethyl, acid labile esters like tert. butyl or, substituted, benzyl esters or hydrogenolytically. Protection of side-chain functions like those of lysine and glutamic or aspartic acid can take place using the aforementioned groups. Protection of thiol, and although not always required, of guanidino, alcohol and imidazole groups can take place using a variety of reagents such as those described in The Peptides, Analysis, Synthesis, Biology, id., or in Pure and Applied Chemistry, 59(3), 331-344 (1987). Activation of the carboxyl group of the suitably protected amino acids or peptides can take place by the azide, mixed anhydride, active ester, or carbodiimide method, especially with the addition of catalytic and racemization-suppressing compounds like 1-N—N-hydroxybenzotriazole, N-hydroxysuccinimide, 3-hydroxy-4-oxo-3,4-dihydro-1,2,3,-benzotria-zine, N-hydroxy-5 norbornene-2,3-dicarboxyimide. In addition, the anhydrides of phosphorus-based acids can be used. See, e.g., The Peptides, Analysis, Synthesis, Biology, supra and Pure and Applied Chemistry, 59(3), 331-344 (1987).
It is also possible to prepare the compounds by the solid phase method of Merrifield. Different solid supports and different strategies are known, see, e.g., Barany and Merrifield in The Peptides, Analysis, Synthesis, Biology, Vol. 2, E. Gross and J. Meienhofer, eds. (Acad. Press, New York, 1980); Kneib-Cordonier and Mullen, Int. J. Peptide Protein Res., 30, 705-739 (1987); and Fields and Noble, Int. J. Peptide Protein Res., 35, 161-214 (1990). The synthesis of compounds in which a peptide bond is replaced by an isostere can, in general, be performed using the previously described protecting groups and activation procedures. Procedures to synthesize the modified isosteres are described in the literature, for instance, for the —CH2—NH— isostere and for the —CO—CH2— isostere.
Removal of the protecting groups and, in the case of solid phase peptide synthesis, the cleavage from the solid support, can take place in different ways, depending on the nature of those protecting groups and the type of linker to the solid support. Usually, deprotection takes place under acidic conditions and in the presence of scavengers. See, e.g., volumes 3, 5 and 9 of the series on The Peptides Analysis, Synthesis, Biology, supra.
Another possibility is the application of enzymes in synthesis of such compounds; for reviews, see, e.g., H. D. Jakubke in The Peptides, Analysis, Synthesis, Biology, Vol. 9, S. Udenfriend and J. Meienhofer, eds. (Acad. Press, New York, 1987).
Although possibly not desirable from an economic point of view, oligopeptides according to the invention could also be made according to recombinant DNA methods. Such methods involve the preparation of the desired oligopeptide thereof by means of expressing a recombinant polynucleotide sequence that codes for one or more of the oligopeptides in question in a suitable microorganism as host. Generally, the process involves introducing into a cloning vehicle (e.g., a plasmid, phage DNA, or other DNA sequence able to replicate in a host cell) a DNA sequence coding for the particular oligopeptide or oligopeptides, introducing the cloning vehicle into a suitable eucaryotic or prokaryotic host cell, and culturing the host cell thus transformed. When a eucaryotic host cell is used, the compound may include a glycoprotein portion.
As used herein, a “functional analogue” or “derivative” of a peptide includes an amino acid sequence or other sequence monomers that have been altered, such that the functional properties of the sequence are essentially the same in kind, not necessarily in amount. An analogue or derivative can be provided in many ways, for instance, through “conservative amino acid substitution.” Also, peptidomimetic compounds can be designed that functionally or structurally resemble the original peptide taken as the starting point but that are, for example, composed of non-naturally occurring amino acids or polyamides. With “conservative amino acid substitution,” one amino acid residue is substituted with another residue with generally similar properties (size, hydrophobicity), such that the overall functioning is likely not to be seriously affected. However, it is often much more desirable to improve a specific function. A derivative can also be provided by systematically improving at least one desired property of an amino acid sequence. This can, for instance, be done by an Ala-scan and/or replacement net mapping method. With these methods, many different peptides are generated, based on an original amino acid sequence but each containing a substitution of at least one amino acid residue. The amino acid residue may either be replaced by alanine (Ala-scan) or by any other amino acid residue (replacement net mapping). In this way, many positional variants of the original amino acid sequence are synthesized. Every positional variant is screened for a specific activity. The generated data are used to design improved peptide derivatives of a certain amino acid sequence.
A derivative or analogue can also be generated, for instance, by substitution of an L-amino acid residue with a D-amino acid residue. This substitution, leading to a peptide that does not naturally occur in nature, can improve a property of an amino acid sequence. It is, for example, useful to provide a peptide sequence of known activity of all D-amino acids in retro inversion format, thereby allowing for retained activity and increased half-life values. By generating many positional variants of an original amino acid sequence and screening for a specific activity, improved peptide derivatives comprising such D-amino acids can be designed with further improved characteristics.
A person skilled in the art is well able to generate analogous compounds of an amino acid sequence. This can, for instance, be done through screening of a peptide library. Such an analogue has essentially the same functional properties of the sequence in kind, not necessarily in amount. Also, peptides or analogues can be circularized, for example, by providing them with (terminal) cysteines, dimerized or multimerized, for example, by linkage to lysine or cysteine or other compounds with side-chains that allow linkage or multimerization, brought in tandem or repeat configuration, conjugated or otherwise linked to carriers known in the art, if only by a labile link that allows dissociation.
As used herein, an “oligopeptide” also includes, for example, an acceptable salt, base, or ester of the oligopeptide or a labeled oligopeptide. As used herein, “acceptable salt” refers to salts that retain the desired activity of the oligopeptide or equivalent compound, but preferably do not detrimentally affect the activity of the oligopeptide or other component of a system that uses the oligopeptide. Examples of such salts are acid-addition salts formed with inorganic acids, for example, hydrochloric acid, hydrobromic acid, sulfuric acid, phosphoric acid, nitric acid, and the like. Salts may also be formed with organic acids such as, for example, acetic acid, oxalic acid, tartaric acid, succinic acid, maleic acid, fumaric acid, gluconic acid, citric acid, malic acid, ascorbic acid, benzoic acid, tannic acid, pamoic acid, alginic acid, polyglutamic acid, and the like. Salts may be formed with polyvalent metal cations such as zinc, calcium, bismuth, barium, magnesium, aluminum, copper, cobalt, nickel and the like or with an organic cation formed from N,N′-dibenzylethylenediamine or ethylenediamine, or combinations thereof (e.g., a zinc tannate salt).
The oligopeptide, or its modification or derivative, can be administered as the entity, as such, or as a pharmaceutically acceptable acid- or base-addition salt, formed by reaction with an inorganic acid (such as hydrochloric acid, hydrobromic acid, perchloric acid, nitric acid, thiocyanic acid, sulfuric acid, and phosphoric acid); or with an organic acid (such as formic acid, acetic acid, propionic acid, glycolic acid, lactic acid, pyruvic acid, oxalic acid, malonic acid, succinic acid, maleic acid, and fumaric acid); or by reaction with an inorganic base (such as sodium hydroxide, ammonium hydroxide, potassium hydroxide); or with an organic base (such as mono-, di-, trialkyl and aryl amines and substituted ethanolamines). A selected peptide and any of the derived entities may also be conjugated to sugars, lipids, other polypeptides, nucleic acids and PNA; and function in situ as a conjugate or be released locally after reaching a targeted tissue or organ.
A pharmaceutical composition for use herein may be administered to the subject parenterally or orally. Such a pharmaceutical composition may consist essentially of (or consist of) oligopeptide and PBS. It is preferred that the oligopeptide is of synthetic origin. Suitable treatment, for example, entails administering the oligopeptide (or salt or ester) in the pharmaceutical composition to the patient intravenously in an amount of from about 0.0001 to about 35 mg/kg body mass of the subject. It may be useful that the pharmaceutical composition consists essentially of from one to three different oligopeptides.
The invention is further described with the aid of the following illustrative examples.
Adult male specific pathogen-free Wistar rats (Harlan CPB, Zeist, The Netherlands), weighing 350 to 400 g were used after a minimum seven-day acclimation period. The animals were housed under barrier conditions and kept at 25° C. with a twelve-hour light/dark cycle. Rats were allowed free access to water and chow (−). All procedures were performed in accordance with the Principles of Laboratory Animal Care (NIH publication No. 86-23, revised 1985) under a protocol approved by the Committee on Animal Research of the Erasmus University (protocol EUR 365).
The rats were fasted overnight but were allowed free access to water before the experiment. Subsequent to endotracheal intubation, the rats were mechanically ventilated with an isoflurane (−) N2O/O2 mixture at 60 breaths/minute. Body temperature was continuously maintained at 37.5° C. by placing the animals on a thermo controlled “half-pipe” (UNO, The Netherlands). Polyethylene tubes (PE-50, Becton Dickinson; St. Michielsgestel, The Netherlands) were flushed with heparin and placed via the right carotid artery in the aorta and in the right internal jugular vein. The animals received no heparin before or during the experiment.
Mean arterial pressures (MAP) was measured using transducers (Becton Dickinson) that were connected in line to an electronic recorder (Hewlett Packard, 78354-A Germany) for electronically calculated mean pressures and continuous measurement of the animal's blood pressure. Under semi-sterile conditions, a median laparotomy was performed and ultrasonic perivascular flow probes (Transonic Systems Inc, Maastricht, The Netherlands) were placed on the common hepatic artery and the portal vein. A supra pubic catheter was placed to monitor the urine production during and after resuscitation.
After an acclimatization period of 20 minutes, the rats were randomized into the following five groups:
The hepatic arterial blood flow (QHA) and hepatic portal venous blood flow (QVP) were measured with transit time ultrasonic perivascular flow probes, connected to an ultrasonic meter (T201; Transonic Systems, Inc., Maastricht, NL). Systemic and hepatic hemodynamics were continuously measured. At regular time points, arterial blood samples were taken. The animals were euthanized by withdrawal of arterial blood via the carotid artery.
Plasma collection and storage: Whole arterial blood was obtained at −15, 30, 60, 90, 120, 150 and 180 minutes after induction of shock via the right carotid artery and collected in duplo. 0.2 ml was placed in tubes (Eppendorf EDTA KE/1.3) to be assayed in the coulter counter (−). 0.5 ml was placed in Minicollect tubes (Bio-one, Greiner) centrifuged for five minutes, immediately frozen, and stored at −80° C., until assayed. All assays were corrected for the hematocrit.
Measurement of cytokines (still in progress): The levels of IL-6 and IL-10 in the serum were determined by an ELISA (R&D Systems Europe Ltd.) according to the manufacturer's instructions.
Histology (still in progress): The alterations in lung, liver, sigmoid and small bowel morphology were examined in sham-operated animals, in animals after trauma-hemorrhage and in animals after trauma-hemorrhage treated with peptide A, B or C. All tissues were collected in duplo. One part was harvested and fixed in formalin (Sigma) and later embedded in paraffin. The other part was placed in tubes (NUNC Cryo Tube™ Vials), quick frozen in liquid nitrogen and stored at −80° C. until assayed.
Mean Arterial Pressure: MAP dropped significantly in all shock groups during the shock phase compared to the control group.
Hematocrit: The hematocrit following trauma-hemorrhage was similar in the different peptide A-, B- and C-treated and non-treated groups. During the shock phase, there was a difference of hematocrit in the control group in comparison with the other groups. From the resuscitation phase (90 minutes) there was no significant difference in hematocrit among the control, trauma-hemorrhage, and peptide groups.
Leukocyte Recruitment: During trauma-hemorrhage, the leukocytes dropped from 100% at TO in all groups to a minimum of 40.0±11.9%, 42.0±8.7%, 47.3±12.4%, 38.2±7.4% in, respectively, the non-treated, peptide A-treated, peptide B-treated and peptide C-treated groups because of leukocyte accumulation in the splancnic microcirculation. There was a significant difference in leukocyte concentration between all treated and non-treated trauma-hemorrhage groups, and the control group during the shock phase. No significant difference was noticed between the peptide A-, B- or C-treated animals and the non-treated animals.
Blood Concentrations of Macrophages and Granulocytes: At 180 minutes after the onset of trauma-hemorrhage, concentrations of circulating macrophages (MD) and granulocytes were significantly lower in the peptide B- and C-treated animals compared with the corresponding experimental group. Blood levels of circulating MD and granulocytes were 5,556±1,698 109/1 in sham-operated animals, whereas blood levels were 6,329±1,965 109/1 after trauma-hemorrhage, and decreased by 29.9% after administration of peptide B (4,432±0.736 109/1) and 39.2% after administration of peptide C (3,846±0.636 109/1) compared with concentrations after trauma-hemorrhage.
Arterial Hepatic Blood Flow: There was a decrease in the arterial hepatic blood flow in the shock group (18.3±14.3%) and in the peptide A (21.3±9.1%), B (18.1±9.0%) and C (21.2±8.6%) groups during the shock period compared with the control group (102.6±23.5%). An increase in blood flow was observed during the reperfusion in the hepatic artery of the shock group (128.9±75.4%) compared with control animals (83.7±24.2%) and the animals treated with peptide B (78.4±28.3%).
Trauma-hemorrhage results in hypoxic stress owing to the absolute reduction in circulating blood volume. In contrast, sepsis is an inflammatory state mainly mediated by bacterial products. It is interesting that these divergent insults reveal similar pathophysiologic alterations in terms of the splancnic circulation.
Hemorrhagic shock significantly increases leukocyte accumulation in the splancnic microcirculation owing to the up-regulation of P selectin. The expression of intercellular adhesion molecules within the intestinal muscular vasculature after hemorrhagic shock promotes the local recruitment of leukocytes, and this inflammatory response is accompanied by subsequent impairment of intestinal function.
The adhesion and extravasation of neutrophils not only contribute to the inflammatory response in the splancnic tissue bed but also induce intestinal microcirculatory failure and dysfunction after severe stress. This is mediated by the induced expression of adhesion molecules, such as selectins and endothelial cell adhesion molecules, on the surface of neutrophils and endothelial cells.
In our shock experiments, leukocyte concentration significantly decreases during hemorrhagic shock compared to the control animals. However, a single dose of peptide B or C administered during resuscitation decreased concentrations of circulating macrophages and granulocytes 120 minutes after the onset of hemorrhagic shock compared to the non-treated animals.
Because some female sex hormones effectively protect the organs from circulatory failure after various adverse circulatory conditions, numerous studies have been performed to clarify the molecular mechanism of, for example, estradiol action with regard to tissue circulation. In this study, a single dose of peptide was administered following trauma-hemorrhage and various parameters were measured at three hours following the induction of shock. Treatment with peptides improved or restored immune functional parameters and cardiovascular functions. Therefore, our results show that administration of short oligopeptides (NMPFs) is beneficial in the treatment of critically ill trauma victims experiencing hemorrhagic shock.
Background: Hemorrhagic shock followed by resuscitation induces a massive pro-inflammatory response, which may culminate into severe inflammatory response syndrome, multiple organ failure and finally death. Treatments aimed at inhibiting the effects of pro-inflammatory cytokines are only effective when initiated before the onset of hemorrhagic shock, which severely limits their clinical application.
Aim: We investigated whether the administration of synthetic oligopeptides (LQGV (SEQ ID NO:2), AQGV (SEQ ID NO:1), LAGV (SEQ ID NO:3)) 30 minutes after induction of hemorrhagic shock reduced the inflammatory response.
Methods: Rats were bled to 50% of baseline mean arterial pressure and one hour later resuscitated by autologous blood transfusion. Thirty minutes after onset of hemorrhagic shock, experimental groups received either one of the synthetic oligopeptides (LQGV (SEQ ID NO:2), AQGV (SEQ ID NO:1), LAGV (SEQ ID NO:3)) or 0.9% NaCl solution. TNF-α and IL-6 plasma levels were determined at fixed time points before and after onset of hemorrhagic shock. Liver, lungs, ileum and sigmoid mRNA levels for TNF-α, IL-6 and ICAM-1 were determined 180 minutes after onset of hemorrhage.
Results: Treatment with either one of the three oligopeptides (LQGV (SEQ ID NO:2), AQGV (SEQ ID NO:1), LAGV (SEQ ID NO:3)) efficiently reduced TNF-α and IL-6 plasma levels, as well as TNF-α and IL-6 mRNA transcript levels in the liver.
Conclusion: Considering these powerful effects of oligopeptides during severe hemorrhagic shock, they may have therapeutic potential with beneficial effects on the hyper inflammation, thereby reducing the late life-threatening tissue and organ damage that is associated with severe hemorrhagic shock.
Introduction: In hemorrhagic shock, there is massive blood loss, which cannot be compensated by the body without treatment. The primary treatment of hemorrhagic shock is to control bleeding and restore intravascular volume to improve tissue perfusion. This treatment induces an inflammatory response, which may culminate into a severe inflammatory response and finally multiple organ dysfunction syndrome (MODS).[1, 2, 3] In addition, approximately 40% of patients develop sepsis as a result of trauma-hemorrhage.[3] Sepsis and MODS are the leading causes of death in critically ill patients in the intensive care units all over the world with mortality rates of about 50%.[4, 5]
The severe inflammatory response due to trauma-hemorrhage is characterized by increased expression of adhesion molecules, such as intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), on sinusoidal endothelial cells and hepatocytes. Furthermore, increased levels of pro-inflammatory cytokines are found systemically and locally in liver, lungs and intestine.[6, 7, 8, 9] The pro-inflammatory cytokines produced are, in particular, tumor necrosis factor alpha (TNF-α), interleukin (IL)-1β and IL-6.[10, 11, 12] These cytokines affect organ integrity/function directly, but also indirectly through secondary mediators, such as nitric oxide, thromboxanes, leukotrienes, platelet-activating factor, prostaglandins, and complement.[13, 14] TNF-α also causes the release of tissue-factor by endothelial cells leading to fibrin deposition and disseminated intravascular coagulation.[15, 16] Cells within the liver, mainly Kupffer cells, but also hepatocytes and sinusoidal endothelial cells, are considered as the main producers of these pro-inflammatory cytokines during hemorrhagic shock.[17]
During the last decade, researchers have focused on the modulation of the systemic inflammatory responses with therapeutic agents aiming at neutralizing the activity of cytokines, especially TNF-α[18] Other researchers used therapeutic agents aiming at the inhibition of TNF-α production.[19] However, most of these therapeutic agents must be administered before the onset of hemorrhagic shock to achieve a therapeutic effect.[19] Clearly, this is almost impossible in a clinical trauma-hemorrhage setting. Therefore, therapies initiated after the onset of severe trauma-hemorrhage and aiming at reducing the production of pro-inflammatory cytokine are more relevant to prevent the events leading to MODS.
During pregnancy, the maternal immune system tolerates the fetus by reducing the cell-mediated immune response while retaining normal humoral immunity.[20] Also, clinical symptoms of cell-mediated autoimmune diseases regress in many patients during pregnancy.[20] The hormone human chorionic gonadotropin (hCG) is mainly secreted by placental syncytiocytotrophoblasts during pregnancy and has been shown to be immunoregulatory.[21, 22, 23] The β-subunit of hCG is degraded by specific proteolytic enzymes.[24] This can lead to the release of several oligopeptides consisting of four to seven amino acids which, because of their role in regulation of physiological processes, are considered regulatory.[25] We successfully demonstrated that synthetic oligopeptides can inhibit the acute inflammatory response, disease severity, and mortality in high-dose lipopolysaccharide-induced systemic inflammatory response syndrome.[26] Considering these powerful regulating effects of synthetic oligopeptides on inflammation, we hypothesized that the administration of such regulatory oligopeptides after severe trauma-hemorrhage could inhibit the massive inflammatory response, associated with this condition. To this end, we used LQGV (SEQ ID NO:2), which is part of the primary structure of loop two of the β-subunit of hCG, and two alanine replacement variants, namely AQGV (SEQ ID NO:1) and LAGV (SEQ ID NO:3).
In this study, we demonstrate that LQGV (SEQ ID NO:2), AQGV (SEQ ID NO:1), and LAGV (SEQ ID NO:3), administered after the induction of hemorrhagic shock in rats, significantly reduced TNF-α and IL-6 plasma levels, which is associated with reduced TNF-α and IL-6 mRNA transcript levels in the liver. This indicates that LQGV (SEQ ID NO:2), AQGV (SEQ ID NO:1), and/or LAGV (SEQ ID NO:3) may have therapeutic potential with beneficial effects on systemic inflammation, thereby reducing organ integrity/function, which is associated with severe hemorrhagic shock.
Adult male specific pathogen-free Wistar rats (Harlan CPB, Zeist, The Netherlands), weighing 350 to 400 g were used. Animals were housed under barrier conditions at 25° C. with a twelve-hour light/dark cycle, and were allowed food and water ad libitum. The experimental protocol was approved by the Animal Experiment Committee under the Dutch Experiments on Animals Act and adhered to the rules laid down in this national law that serves the implementation of “Guidelines on the protection of experimental animals” by the Council of Europe (1986), Directive 86/609/EC.
Synthetic oligopeptides: The oligopeptides (LQGV (SEQ ID NO:2), AQGV (SEQ ID NO:1), and LAGV (SEQ ID NO:3)) were synthesized by Ansynth Service B.V. (Roosendaal, The Netherlands) and dissolved in 0.9% NaCl at a concentration of 10 mg/ml.
Surgical procedures: Rats were food deprived overnight before the experiment, but were allowed water ad libitum. Rats were anesthetized using a mixture of N2O/O2 isoflurane (Pharmachemie B.V., Haarlem, The Netherlands). Body temperature was continuously maintained at 37.5° C. by placing the rats on a thermo controlled “half-pipe” (UNO, Rotterdam, The Netherlands). Endotracheal intubation was performed, and rats were ventilated at 60 breaths per minute with a mixture of N2O/O2 2% isoflurane. Polyethylene tubes (PE-50, Becton Dickinson; St. Michielsgestel, The Netherlands) were flushed with heparin and placed via the right carotid artery in the aorta and in the right internal jugular vein. The rats received no heparin before or during the experiment.
Experimental procedures: After an acclimatization period of 15 minutes, the rats were randomized into five different groups: 1) sham, 2) hemorrhagic shock (HS), 3) hemorrhagic shock with LQGV (SEQ ID NO:2) treatment (HS/LQGV (SEQ ID NO:2)), 4) hemorrhagic shock with AQGV treatment (HS/AQGV (SEQ ID NO:1)) and 5) hemorrhagic shock with LAGV (SEQ ID NO:3) treatment (HS/LAGV (SEQ ID NO:3). Hemorrhagic shock was induced by blood withdrawal, reducing the circulating blood volume until a mean arterial pressure (MAP) of 50% of normal mmHg was reached. This level of hypotension was maintained for 60 minutes. After 30 minutes, rats received either a single bolus injection of 10 mg/kg LQGV (SEQ ID NO:2), AQGV (SEQ ID NO:1), LAGV (SEQ ID NO:3), or 0.9% NaCl solution. The peptides and dosage were based on previous studies, in which we performed dose-escalation experiments (manuscript in preparation). Sixty minutes after induction of hemorrhagic shock, rats were resuscitated by autologous blood transfusion over a period of 30 minutes and monitored for another 120 minutes, after which they were sacrificed (
Plasma collection and storage: Arterial blood was obtained 15 minutes before and 30, 60, 90, 120, 150 and 180 minutes after onset of hemorrhage (
Measurements of Mean Arterial Pressure: During the experiments, mean arterial pressure (MAP) was continuously measured using transducers (Becton Dickinson) that were connected in line to an electronic recorder (Hewlett Packard, 78354-A, Germany).
Tissue collection and storage: Liver, lungs, ileum and sigmoid were surgically removed at the end of the experiment, snap-frozen, and stored at −80° C., until assayed.
Measurement of cytokines: TNF-α and IL-6 plasma levels were determined by ELISA (R&D Systems Europe Ltd., Abingdon, UK), according to the manufacturer's instructions.
Evaluation of mRNA levels by real-time quantitative (RQ)-PCR: RNA was isolated using a QIAGEN kit (QIAGEN, Hilden, Germany), according to the manufacturer's instructions. TNF-α, IL-6 and ICAM-1 transcripts were determined by RQ-PCR using an Applied Biosystems 7700 PCR machine (Foster City, Calif., USA) as described previously.[27] TNF-α, IL-6 and ICAM-1 expression was quantified by normalization against GAPDH. Primer probe combinations used are listed in Table 1.
Statistical analysis: Statistical analysis was performed using SPSS version 11 software (SPSS Inc., Chicago, Ill.). Inter-group differences were analyzed with Kruskal-Wallis statistical test. If Kruskal-Wallis statistical testing resulted in a p<0.05, a Dunn's Multiple Comparison test was performed and p<0.05 was considered statistically significant.
Induction of hemorrhagic shock: Lowering the MAP to 50% of normal induced hemorrhagic shock, which was successfully maintained for 60 minutes in all four experimental groups (
Oligopeptide treatment reduces pro-inflammatory cytokine plasma levels: The therapeutic capacity of three synthetic oligopeptides (LQGV (SEQ ID NO:2), AQGV (SEQ ID NO:1), LAGV (SEQ ID NO:3)) related to the primary structure of loop two of the β-subunit of hCG was evaluated in a rat hemorrhagic shock model. Before induction of hemorrhage, TNF-α plasma levels were comparable in all five groups (˜15 to 24 pg/ml) (
Oligopeptide treatment reduces TNF-α and IL-6 but not ICAM-1 mRNA levels in the liver: Because oligopeptide treatment clearly decreased the TNF-α and IL-6 plasma levels, we analyzed mRNA levels in liver, lungs, ileum and sigmoid tissues at 180 minutes after the onset of hemorrhagic shock. In the liver, TNF-α transcripts were significantly increased in the HS group as compared to the sham group. Oligopeptide treatment was associated with decreased TNF-α transcripts in the liver as compared to non-treated HS rats with only HS/LQGV (SEQ ID NO:2) showing a significant reduction as compared to HS (p<0.01;
In the HS group, IL-6 transcripts in the liver were increased ˜83 times as compared to the sham group (p<0.001;
ICAM-1 transcript levels in the liver were significantly increased in the HS group as compared to the sham group (
In this study, we used a rat model of hemorrhagic shock and demonstrated that administration of synthetic oligopeptides (LQGV (SEQ ID NO:2), AQGV (SEQ ID NO:1), LAGV (SEQ ID NO:3)) 30 minutes after shock induction efficiently reduces the pro-inflammatory cytokine levels associated with this condition. Our data demonstrate this to be a likely consequence of reduced expression of pro-inflammatory cytokine mRNA transcript levels in the liver.
Hemorrhagic shock is associated with an early adherence of leukocytes to the vascular endothelium as a result of a decreased blood volume.[28] In our model, a decrease in the percentage of leukocytes was detected in all four experimental groups after blood withdrawal. This indicates that all experimental groups experienced hemorrhagic-induced shock. Resuscitation resulted in an increase of the percentages of leukocytes in the experimental groups.
Hemorrhagic shock followed by resuscitation induces a severe inflammatory response, which is characterized by an exaggerated production of early pro-inflammatory cytokines, such as TNF-α, IL-1β, and subsequently IL-6.[10, 11, 12] TNF-α is a key mediator of the innate immune system that is crucial for the generation of a local protective immune response against infectious or non-infectious agents.[9] However, uncontrolled massive TNF-α production is lethal, as it spreads via the bloodstream into other organs, thereby inducing tissue damage and promoting the production of secondary pro-inflammatory mediators, such as IL-6.[10, 11]
Despite improvement in treatment strategies, trauma-hemorrhage patients may still develop severe inflammatory response that leads too MODS and finally death. Experimental treatment strategies aimed at neutralizing bioactive cytokines, such as monoclonal antibodies against TNF-α, have been successfully applied in several inflammatory disorders, including Crohn's disease and Rheumatoid Arthritis.[29, 30] However, clinical studies using monoclonal antibodies against TNF-α showed no clinical effect in trauma-patients.[31] It has been suggested that TNF-α neutralizing antibodies cause the accumulation of a large pool of TNF-α/anti-TNF-α pool, which act as a slow-release reservoir that may lead to increased constant active TNF-α[32] Therefore, aiming at therapies that decrease the production of TNF-α and IL-6 may be more beneficial in limiting tissue damage and mortality rates in trauma-hemorrhage patients than neutralization of already produced cytokines.
In hemorrhagic shock, TNF-α is secreted within minutes after cellular stimulation, while production stops after three hours, and TNF-α plasma levels become almost undetectable.[9] We demonstrate that regulatory oligopeptides (LQGV (SEQ ID NO:2), AQGV (SEQ ID NO:1), LAGV (SEQ ID NO:3)), administered 30 minutes after the induction of hemorrhagic shock significantly reduced TNF-α and IL-6 plasma levels. Whether the effect on IL-6 production is direct or indirect due to reduced TNF-α, plasma levels cannot be concluded from our data. Nevertheless, establishing a reduction of IL-6 is of clinical importance, because high IL-6 plasma levels correlate with poor outcome and decreased survival in patients with severe trauma and infection.[33, 34] Cells within the liver are considered as the main producers of pro-inflammatory cytokines during hemorrhagic shock.[17] TNF-α and IL-6 transcript levels were significantly increased in the livers of the HS group. LQGV (SEQ ID NO:2), AQGV (SEQ ID NO:1), or LAGV (SEQ ID NO:3) treatment was associated with a reduction in TNF-α and IL-6 liver transcripts, which may be indicative of decreased transcriptional activation. Another important characteristic of endothelial cells and hepatocytes during hemorrhagic shock is increased expression of the adhesion molecule ICAM-1.[7, 8] Our study confirms the increased ICAM-1 expression in the liver after hemorrhagic shock. However, LQGV (SEQ ID NO:2), AQGV (SEQ ID NO:1), or LAGV (SEQ ID NO:3) treatment did not result in reduced ICAM-1 expression. This could be due to the inability of oligopeptides to interfere with induction of ICAM-1 transcription. In lungs, ileum and sigmoid, we detected no effect of hemorrhagic shock on the induction of TNF-α, IL-6 and ICAM-1 transcripts. This confirms that the liver is the first organ in which the inflammatory response is initiated after hemorrhagic shock and fluid resuscitation.[15, 31, 32]
In literature, it is well described that hCG can regulate the immune system, because of its putative role in preventing the rejection of the fetal allograft during pregnancy.[35, 36] Human CG exerts its function by binding to specific membrane-bound receptors, which activate second messengers.[37] The oligopeptides are expected to cross cell membranes without requiring membrane-bound receptors[38] and exert their effects intracellularly. This study and ongoing studies in our laboratory demonstrate that these oligopeptides have a distinct regulating effect on the expression of genes involved in inflammatory pathways and immunity. Nevertheless, investigation on the mechanism of action of hCG-related peptides regulate gene expression are necessary.
Recently a study was published in which the dipeptide AG inhibited the mRNA expression of pro-inflammatory cytokines in the liver after hemorrhagic shock.[39] However, a very high peptide dose of AG was required (150 mg/kg), where we observed clear effects using 10 mg/kg in our study. Nevertheless, this and our study indicate that the use of specific oligopeptides can be considered as therapeutic agents for treatment of the inflammatory response after severe trauma.
In summary, a single administration of a synthetic oligopeptide (LQGV (SEQ ID NO:2), AQGV (SEQ ID NO:1), LAGV (SEQ ID NO:3) after the induction of severe trauma-hemorrhage reduces the subsequent pro-inflammatory response. These data suggest that these oligopeptides have therapeutic potential, in minimizing the late life-threatening tissue and organ damage that is associated with severe trauma-hemorrhage.
This application claims the benefit, under 35 U.S.C. § 119(e), of the filing date of U.S. Provisional Patent Application Ser. No. 60/901,155, filed Feb. 12, 2007, for “TREATMENT OF TRAUMA-HEMORRHAGE WITH SHORT OLIGOPEPTIDES,” and to U.S. Provisional Patent Application Ser. No. 60/961,841, filed Jul. 23, 2007, for “TREATMENT OF TRAUMA-HEMORRHAGE WITH SHORT OLIGOPEPTIDES”, the contents of the entirety of each of which are hereby incorporated by this reference.
| Number | Date | Country | |
|---|---|---|---|
| 60901155 | Feb 2007 | US | |
| 60961841 | Jul 2007 | US |
