To Prepare the Suitable Preparation of Fig

To Prepare the Suitable Preparation of Fig

Title of the Topic:
“CARDIOPROTECTIVE POTENTIAL OF FIG (ficuscarica)IN ISOPROTERENOL INDUCED MYOCARDIAL DAMAGE IN RATS”
BRIEF RESUME OF THE INTENDED WORK:
6.1 Need of study:
It is undisputed that dietary habits affect coronary risk factors and hence the risk of a coronary event. In the search for bioactive components in foods that favorably affect cardiovascular disease (CVD) risk, nuts have begun to attract attention1. Epidemiologic studies have consistently demonstrated an association between nut and dry fruits consumption and coronary heart disease (CHD) morbidity and mortality in different population groups 2. Compared with people who ate nuts and dry fruits < 1 time/wk, those who ate them 1–4 times/wk had a 25% reduced risk of dying from CHD, people who ate nuts ≥ 5 times/wk experienced an50% reduction in risk 3. Nut and dry fruit consumption may not only offer protection against heart disease, but also increase longevity 4. Recently, the benefits of nuts were acknowledged by the U.S. FDA when they approved a qualified health claim that eating nuts (1.5 oz/d, 42.8 g/d) may reduce the risk of CHD 5. There is substantial evidence that nuts and some dry fruits may have favorable effects on CHD through a variety of mechanisms. The most extensively studied mechanism involves the lipid-lowering effects. Nuts are good sources of unsaturated fatty acids [monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA)], known for their favorable effects on blood lipids. Furthermore, evidence suggests that components in nuts further reduce total cholesterol (TC) and LDL cholesterol (LDL-C) concentrations beyond the effects predicted by equations based solely on fatty acid profiles6,7. In particular, the magnitude of the cholesterol-lowering effect was shown to be 25% greater than would be predicted based on the fatty acid profiles of the test diets studied2. Therefore, the possible mechanisms whereby nuts may improve lipid profiles do not rely exclusively on the beneficial action of unsaturated fatty acids (PUFA and MUFA) but may include the effects of fiber, micronutrients such as vitamin E and C, folic acid, copper, magnesium, plant protein (e.g., arginine), plant sterols, and phenolic components2.
Myocardial infarction is the commonest single cause of death in many parts of the world. Its therapy includes administration of thrombolytic agents, anticoagulants, -blockers etc., or surgical angioplasty or coronary bypass surgery8. It has been shown that cardiac renin angiotensin system (RAS) rather than the circulatory system may play an important role in myocardial infarction. Recent experimental andlarge clinical trials strongly indicate the role forangiotensin converting enzyme (ACE) inhibitors andangiotensin II (A II) receptor antagonists (AT1 antagonists)in limiting myocardial ischemia-reperfusion inducedinjury9. Coronary vasodilatation due to interferencewith ACE or complex changes in systemichemodynamics that reduce oxygen demand or inhibitionof cardiac A II formation or blocking the receptorcompetitively for cardiac A II in virtually all tissues,including myocardium and vascular tissues mayaccount for the cardioprotection. . In addition, altered prostaglandin production or oxygen free radical scavenging properties of ACE inhibitors have been postulated to reduce myocardial infarction10. Ramipril is long acting ACE inhibitor and it acts as a prodrug of the diacidramiprilat, its active metabolite. . Further, reduction of reperfusion arrhythmias in the ischemic isolated rat heart by angiotensin converting enzyme inhibitors was also demonstrated 11.
One of the common dry fruit used widely is figs. The health benefits of figs or anjeer includetreatment ofsexual weakness, constipation, indigestion, piles, diabetes, cough, bronchitis, and asthma. It also helps in gaining weight after illness.Health benefits of figs can be attributed to the presence of minerals and vitamins in them. Figs contain vitamin A, vitamin B1, vitamin B2, calcium, iron, phosphorus, manganese, sodium, potassium and chlorine.However, traditional claims and the hidden potentials are not proven scientifically. Thus the present study is designed to evaluate the cardioprotective potential of fig in isoproterenol induced acute and chronic myocardial damage in rats.
6.2 Review of literature
In India, for the past five decades, rates of coronary disease among urban population have risen from 4% to 11%. Hence it is very essential that we take precautionary measures to ensure that the disease is curbed.
Ficuscaricais a deciduous shrub or small tree, native to the eastern Mediterranean area and to Asia Minor. It has proven to show promising anti-obesity activity. The fruits of figs contain a high amount (70%) of sugar (glucose and fructose in the same quantity), pectins, flavonoids and vitamins12. Potential hypolipidemic effectsin diabetic rats have also been demonstrated13. It is proposed that the flavonoids contained in the Fig aqueous extract may contribute to the hypolipidemic action, as it has been demonstrated that some flavonoids, such as aringenin, inhibit HMGCoAreductase and ACAT (Acyl-CoAcholesterylacyltransferase) activities in high cholesterol-fed rats14. Figs are also rich in potassium therefore daily use of fig helps in controlling blood pressure and keeps away from hypertension and heart diseases.
Biochemical, pharmacological and molecular biological data provide evidence for the presence of a cardiac RAS. The potential usefulness of ACE inhibitors in myocardial ischemia may be explained by intracardiac suppression of angiotensin II generation and bradykinin degradation15. Renal RAS is salt sensitive. Renal renin secretion is directly proportional to sodium excretion through kidneys. In healthy Na+ replete animals and humans, a single dose of ACE inhibitor has little or no effect on supine or erect systemic blood pressure whereas the same lowers blood pressure substantially in normal subjects when they have been depleted of Na+16.
In the early 1980s, angiotensin converting enzyme inhibitors were introduced into the clinical arena. Since then, this class of drug has emerged as one of the most important cardiovascular therapeutic agents in modern medicine. At about the same cellular and molecular biologic techniques were introduced to cardiovascular research. Molecular research has enabled physiologists and bio-chemists to re-examine, in greater depth, many of the basic concepts of cardiovascular regulation. One of the outcomes of molecular research is an improved understanding of the biology of the reninangiotensin system17. It is now appreciated that angiotensin is not only synthesized in the circulation but also locally in many tissues. The concept of an autocrine-paracrine mechanism of reninangiotensin action has evolved from the traditional endocrine concept 18. Inhibitors of reninangiotensin system, such as the angiotensin converting enzyme (ACE) inhibitor may exert much of their pharmacological effects via the blockade of local angiotensin production 19. This mechanism may explain the general efficacy of this class of drug in the treatment of several major cardiovascular disorders, irrespective of the plasma renin level of the patients. Clinical and experimental datasuggest that ACE inhibition might reduce coronary heart disease risk in hypertensive subjects, improve survival in patients with heart failure, and may influence coronary ischaemia and reperfusion injury.
6.3 Objective of study
The objective of the present research is to carry out evaluation of cardioprotective potential of fig in isoproterenol induced myocardial damage in rats.
SPECIFIC OBJECTIVES:
  • To prepare the suitable preparation of fig .
  • To carryout preliminary phytochemical investigation of constituents of fig.
  • To arrive at the therapeutic dose range after acute toxicity studies following WHO guidelines.
  • To study the biochemical and antioxidant profile in serum and heart tissue homogenate upon chronic administration of fig.
  • To explore the role of figduring isoproterenol induced acute myocardial derangement in rats.
  • To study the benefits of fig pretreatment in isoproterenol mediated chronic myocardial damage in rats.

MATERIALS AND METHODS:
7.1 Source of Data:
Data will be obtained from laboratory based studies by using Sprague dawley rats of either sex weighing between 150-200 gms maintained at room temperature having free access to food (std pellet diet), tap water adlibitum. These studies will be carried out in intact animal that will be supported by biochemical data and histopathological studies.
7.2 Method of Collection of Data:
Chemicals and reagents will be procured from standard companies. Isoproterenol induced myocardial damage will be used as model to evaluate cardioprotective efficacy. Suitable biochemical and histological investigation will be carried out in animal model. The data collected will be based on animal experimentation as per the parameters studied under each animal model.
Fig preparation will be suspended in distilled water and administeredorally once a day at a constant volume of 0.5 ml/100 g of body weight. These doses will be selected on the basisof our preliminary toxicity studies. The control animals receivedonly the vehicle in the same volume andthrough the same route.
Experimental protocol
The cardioprotective role of fig will be determined in isoproterenol induced ischemia-reperfusion rats. The Sprague dawley rats of either sex will be divided into following groups consisting of six animals each:
  • Group-I- animals kept as control without pretreatment
  • Group II- ISO control
  • Group-III- Fig low dose (30 days oral treatment)
  • Group-IV- Fig high dose (30 days oral treatment)
  • Group-V- Ramipril (1mg/kg, orally for ten days)20
Isoproterenol induced chronic myocardial damage in rats:
During 30 days of fig and ten days of ramipril administration, animals in all groups except group I will receive 3 mg/kg/day subcutaneously21. During treatment, haemodynamic parameters such as body weight, physiological changes and electrocardiographic observations will be noted. At the end of treatment, blood samples will be collected and serum will be separated. Heart tissue homogenate will be prepared in 0.25 M sucrose (10%) and both serum and heart tissue homogenate will be studied for CK-MB, LDH, SOD andCatalase. Microscopic slides will be prepared to study histopathological changes.
Isoproterenol (ISO) induced acute myocardial necrosis in rats22
At the end of treatment of animals as mentioned in experimental protocol, blood samples will be collected and serum will be separated. Influence of chronic therapy of fig will be determined by estimating LDH, CK-MB and TBARS in serum. Subsequently, ISO (150 mg/kg, s.c) will be administered for two consecutive days. Symptoms and mortality in each group will be recorded and compared with those of the rats given ISO alone. After anesthetizing the rat with a combination of ketamine hydrochloride (75mg/kg, i.p) and xylazine (8.0mg/kg, i.p), leads will be attached to the dermal layer of both the front paws and hind legs and recording will be made on polygraph with the help of electrodes ECG system (subcutaneous lead II method). Blood samples will be collected and separated serum will be evaluated again for estimating LDH and CK-MB23. Forty-eight hours after the first ISO administration, the rats will be sacrificed and autopsied. Three excised hearts will be homogenized to prepare heart tissue homogenate (HTH) using sucrose (0.25 M). The endogenous biological markers such as LDH, CK-MB and antioxidants (Superoxide dismutase and catalase)24,25 will be determined in heart tissue homogenate. Microscopic slides of remaining three hearts will be prepared for studying histopathological studies.The myocardial damage based on histopathologicalwill be determined with the help of histopathologist in diagnostic centre by giving scores depending on the intensity as follows 26; no changes – score 00; mild – score 01 (focal myocytes damage or small multifocal degeneration with slight degree of inflammatory process); moderate – score 02 (extensive myofibrillar degeneration and/or diffuse inflammatory process); marked – score 03 (necrosis with diffuse inflammatory process).
Statistical analysis:
The statistical significance will be assessed using one-way analysis of variance (ANOVA) followed by Dunnet comparison test. The values will be expressed as mean ± SEM and p < 0.05 will be considered significant.
7.3 Does the study require any investigation or interventions to be conducted on patients or the human or animals? If so please describe briefly:
YES, Study requires investigation on animals. The effects of the drug will be studied on various parameters using rats as experimental animals.
7.4 Has ethical clearance been obtained from your institute
Ethical Committee approval letter is enclosed.
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