Ipseeta Mohanty

Cardioprotection from ischemia and reperfusion injury by Withania somnifera: A hemodynamic, biochemical and histopathological assessment

The efficacy of Withania somnifera (Ws) to limit myocardial injury after ischemia and reperfusion was explored and compared to that of Vit E, a reference standard known to reduce mortality and infarct size due to myocardial infarction. Wistar rats (150–200 g) were divided into six groups and received orally saline (sham, control group), Ws-50/kg (Ws control and treated group) and Vit E-100 mg/kg (Vit E control and treated group) respectively for 1 month. On the 31st day, rats of the control, Vit E and Ws treated groups were anesthetized and subjected to 45 min occlusion of the LAD coronary artery followed by 60 min reperfusion. Hemodynamic parameters: systolic, diastolic and mean arterial pressure (SAP, DAP, MAP), heart rate (HR), left ventricular end diastolic pressure (LVEDP), left ventricular peak (+) LVdP/dt and (−) LVdP/dt were monitored. Hearts were removed and processed for histopathological and biochemical studies: Myocardial enzyme viz, creatin phosphokinase (CPK), and antioxidant parameters: malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHPx) were estimated. Postischemic reperfusion produced significant cardiac necrosis, depression of left ventricular functions (MAP, LVEDP, (+) and (−) LVdP/dt) and a significant fall in GSH (p < 0.01), SOD, CAT(p < 0.05), LDH and CPK (p < 0.01) as well as an increase in MDA level (p < 0.05) in the control group rats as compared to sham group. The changes in levels of protein and GPx was however, not significant. Ws and Vit E favorably modulated most of the hemodynamic, biochemical and histopathological parameters though no significant restoration in GSH, MAP (with Vit E) were observed. Ws on chronic administration markedly augmented antioxidants (GSH, GSHPx, SOD, CAT) while Vit E did not stimulate the synthesis of endogenous antioxidants compared to sham. Results indicate that Ws significantly reduced myocardial injury and emphasize the beneficial action of Ws as a cardioprotective agent.

Effect of Curcuma longa and Ocimum sanctum on myocardial apoptosis in experimentally induced myocardial ischemic-reperfusion injury

BackgroundIn the present investigation, the effect of Curcuma longa (Cl) and Ocimum sanctum (Os) on myocardial apoptosis and cardiac function was studied in an ischemia and reperfusion (I-R) model of myocardial injury.MethodsWistar albino rats were divided into four groups and orally fed saline once daily (sham, control IR) or Cl (100 mg/kg; Cl-IR) or Os (75 mg/kg; Os-IR) respectively for 1 month. On the 31st day, in the rats of the control IR, Cl-IR and Os-IR groups LAD occlusion was undertaken for 45 min, and reperfusion was allowed for 1 h. The hemodynamic parameters{mean arterial pressure (MAP), heart rate (HR), left ventricular end-diastolic pressure (LVEDP), left ventricular peak positive (+) LVdP/dt (rate of pressure development) and negative (-) LVdP/dt (rate of pressure decline)} were monitored at pre-set points throughout the experimental duration and subsequently, the animals were sacrificed for immunohistopathological (Bax, Bcl-2 protein expression & TUNEL positivity) and histopathological studies.ResultsChronic treatment with Cl significantly reduced TUNEL positivity (p < 0.05), Bax protein (p < 0.001) and upregulated Bcl-2 (p < 0.001) expression in comparison to control IR group. In addition, Cl demonstrated mitigating effects on several myocardial injury induced hemodynamic {(+)LVdP/dt, (-) LVdP/dt & LVEDP} and histopathological perturbations. Chronic Os treatment resulted in modest modulation of the hemodynamic alterations (MAP, LVEDP) but failed to demonstrate any significant antiapoptotic effects and prevent the histopathological alterations as compared to control IR group.ConclusionIn the present study, significant cardioprotection and functional recovery demonstrated by Cl may be attributed to its anti-apoptotic property. In contrast to Os, Cl may attenuate cell death due to apoptosis and prevent the impairment of cardiac performance.

Withania somnifera provides cardioprotection and attenuates ischemia-reperfusion induced apoptosis

BACKGROUND & AIMS The present study was undertaken to evaluate the cardioprotective mechanisms of Withania somnifera (Ws), in the setting of ischemia and reperfusion (IR) injury. METHODS Wistar rats were divided into three groups and received orally saline (sham, control IR) and Ws-50 mg/kg (Ws-IR), respectively, for 1 month. On the 31st day, in the rats of control IR and Ws-IR group, LAD coronary artery occlusion was undertaken for 45 min followed by 1 h reperfusion. Subsequently, all the animals were sacrificed for biochemical, immunohistochemical {Bax and Bcl-2 protein}, terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) positivity and histopathological studies. RESULTS Post-ischemic reperfusion injury resulted in significant cardiac necrosis, apoptosis, decline in antioxidant status and elevation in lipid peroxidation in the IR control group as compared to sham. Ws prior-treatment favorably restored the myocardial oxidant-antioxidant balance, exerted marked anti-apoptotic effects {upregulated Bcl-2 (p<0.001) protein, decreased Bax (p<0.01) protein, and attenuated TUNEL positivity (p<0.01)}, and reduced myocardial damage as evidenced by histopathologic evaluation. CONCLUSIONS The antioxidant and anti-apoptotic properties of Ws may contribute to the cardioprotective effects.

Lycopene prevents sugar-induced morphological changes and modulates antioxidant status of human lens epithelial cells.

Cataract is a multifactorial disease. Osmotic stress, together with weakened antioxidant defence mechanisms, is attributed to the changes observed in human diabetic cataract. Epidemiological studies provide evidence that nutritional antioxidants slow down the progression of cataract. The usefulness of lycopene, a dietary carotenoid, in the pathogenesis of human cataracts has not been studied so far. Since the epithelium is the metabolic unit of the lens, the effect of lycopene on galactose-induced morphological changes and antioxidant status of human lens epithelial cells (HLEC) in culture was evaluated in the present study. HLEC of fresh cadaver eyes obtained from an eye bank were cultured in medium supplemented with fetal calf serum (200 ml/l). On confluency, the cells were subcultured in medium containing either 30 mm-d-galactose or 30 mm-d-galactose+lycopene (5, 10 or 20 microm) for 72 h. The cells were observed under the phase-contrast microscope and transmssion electron microscope for any morphological changes and then harvested for the estimation of various biochemical variables. Malondialdeyde, glutathione and antioxidant enzymes were significantly altered in the control as compared with the normal cultures. Vacuolization was also observed in the presence of galactose. Addition of lycopene confers significant protection against these changes in HLEC.

Cardioprotective response to chronic administration of vitamin E in isoproterenol induced myocardial necrosis: Hemodynamic, biochemical and ultrastructural studies

The present study evaluated the cardioprotective potential of vitamin-E by studying its effect on hemodynamic parameters, lipid peroxidation, myocyte injury marker and ultrastructural changes in model of isoproterenol-induced myocardial necrosis in rats. Wistar albino male rats (150–200 g) were randomly divided into saline, ISP control, and vit E groups. Vitamin E group was administered vitamin E at a dose of 100mg/kg/day while saline and ISP control groups received saline orally for one month. On 29th and 30th day, ISP (85 mg/kg, sc) was administered at an interval of 24 h to vit E and ISP control rats. On 31st day, rats of all groups were anesthetized and hemodynamic parameters were recorded. At the end of experimentation, animals were sacrificed; hearts were excised and processed for biochemical and ultrastructural studies. ISP administration produced marked cardiac necrosis as evidenced by significant decrease in my ocardial creatine kinase-MB as well as increase in malonaldialdehyde levels. ISP-induced myocardial necrosis resulted in myocardial dysfunction as evidenced by significant depression in heart rate and mean arterial pressure in the ISP control group as compared to saline control. Salient ultrastructural changes including extensive loss of myofibrils, muscle necrosis, loss of mitochondria, and formation of several intracytoplasmic vacuoles and lipid droplets further confirmed the ISP-induced myocardial damage. However, subsequent to ISP challenge, vit E treatment significantly preserved the myocardium by restoring myocardial CK-MB activity, inhibiting the ISP-induced lipid peroxidation and ultrastructural changes. Additionally, pre-and co-treatment of vit E prevented the deleterious ultrastructural changes caused by ISP. These beneficial effects of chronic vit E treatment also translated into significant restoration of the altered hemodynamic parameters. The present study clearly demonstrated the cardioprotective potential of vit E at dose of 100 mg/kg in ISP-induced model of myocardial necrosis in rats. The significant restoration of altered hemodynamic parameters, myocardial CK-MB activity, prevention of ISP-induced rise in lipid peroxidation and ultrastructural changes may confirm its cardioprotective effect.

Pyruvate Inhibits Galactosemic Changes in Cultured Cat Lens Epithelial Cells

An attempt was made to maintain cat lens epithelial cells (CLEC) in culture and study the morphology, growth and survival of these cells in vitro. The influence of incorporation of galactose (30 mM) into the culture medium on the morphology and biochemistry of CLEC in the primary culture was then investigated. To establish the effect of galactose on CLEC, various biochemical parameters associated with galactosemic cataract such as aldose reductase (AR), Na+K+ATPase, glutathione, polyol and soluble/insoluble proteins were estimated after 24 h of incubation. The effect of pyruvate (5 mM), a ‘physiological antioxidant’, on the changes induced by galactose in CLEC was studied. CLEC in culture showed regular hexagonal cells with prominent nuclei. The CLEC culture attained confluency in 11 days during primary culture and semiconfluency in 14 days in two subsequent passages. Vacuolization and significantly raised AR activity, polyol levels and insoluble protein contents were observed; they had no effect on Na+K+ATPase and soluble protein after 24 h of incubation in the culture medium with galactose. Supplementation of pyruvate (5 mM) resulted in a lesser number of vacuoles together with a positive modulation of these parameters.

Pyruvate modulates antioxidant status of cultured human lens epithelial cells under hypergalactosemic conditions

Lens epithelial cells are the metabolic unit of the lens and antioxidant enzymes are mainly concentrated here. The purpose of this study was to maintain human lens epithelial cells (HLEC) in culture and examine the status of antioxidant enzymes (glutathione peroxidase (GSHPx), catalase (CAT), glutathione-S-transferase (GST)), lipid peroxidation product malondialdehyde (MDA) and glutathione (GSH) levels in these cells under normal as well as hypergalactosemic (30 mM galactose) conditions. Further, effect of pyruvate, a physiological antioxidant has also been evaluated on these parameters. For conducting experiments, anterior capsule specimens obtained from fresh cadaver eyes from eye bank were cultured in Dulbeccos Modified Eagles Medium (DMEM) supplemented with 20% fetal calf serum. Upon confluency, the cells were subcultured in three separate flasks containing DMEM alone (normal group), DMEM + 30 mM D-galactose (control group), DMEM + 30 mM D-galactose + 5 mM pyruvate (test group) and incubated for 24 or 72 h. These cells were observed under the phase contrast microscope for any morphological changes and harvested for the estimation of various antioxidant parameters. Our results show significant weakened antioxidant defense in HLEC when incubated in the presence of galactose as compared to normal. Addition of pyruvate significantly modulated levels of GSH, MDA, GSHPx, CAT and GST.

Medicinal Herbs can Play Significant Role in Attenuation of Ischemia and Reperfusion Injury

Nature has been a source of medicinal treatments for thousands of years and plant-derived products continue to play an essential role in the primary health care of about 80-85% of the world’s population. Medicinal herbs are widely used in Ayurveda, the Indian System of Medicine and have been observed to possess numerous activities with regard to cardiovascular system viz. antiplatelet, hypolipidemic, anti-inflammatory, hypoglycemic and hypotensive actions. Hence, these herbal extracts traditionally used have been evaluated scientifically in the present study with an aim to define the role of these agents in limiting the deleterious effects of myocardial ischemia and reperfusion (IR) injury by providing scientific data to validate their use as prophylactic approaches or as an adjunct to standard treatment (synthetic compounds employed in conventional treatment protocols) of ischemic heart disease. The efficacy of Withania somnifera (Ws), Curcuma longa (Cl) and Ocimum sanctum (Os), and herbal combination (HCB) including {Ws (50 mg/kg) + Cl (100 mg/kg) + Os (75 mg/kg} to limit injury in the setting of myocardial ischemia and reperfusion was explored in the present study. An open chest left anterior descending coronary artery (LAD) occlusion and reperfusion induced myocardial injury was used as the experimental model. Wistar albino rats were divided into ten groups and orally fed saline once daily (sham, control IR) or medicinal herbs (Ws/Cl/Os/HCB; Ws-IR, Cl-IR/Os-IR/HCB-IR) respectively for 1 month. On the 31st day in the rats of the Control IR and Ws-IR, Cl-IR/Os-IR/HCB-IR groups, LAD was occluded for 45 min, and reperfused for 1 h. Hemodynamic parameters were recorded at preset points and subsequently sacrificed for biochemical, immunohistochemical and pathological studies. In the control IR group, significant ventricular dysfunction, cardiac necrosis, apoptosis; decline in antioxidant status and elevation in lipid peroxidation was observed. Chronic oral treatment with HCB per se for 1 month resulted in significant enhancement of the myocardial endogenous antioxidant enzymes. Pretreatment with Ws, Cl and the herbal combination exerted significant cardioprotective effects in the experimental model of myocardial injury. The most remarkable observation of the present study was that cardioprotective effect exerted by HCB treatment was found to be superior to that shown by singular treatment with individual herbal extracts. The combination of herbal extracts was found to significantly ameliorate the ischemia and reperfusion cardiomyocyte apoptosis, cardiac dysfunction, compromised antioxidant status and histopathologic alterations as compared to control IR group. Cardioprotection by HCB treatment may be attributed to its favorable hemodynamic effects, myocardial adaptogenic properties, and significant antioxidant and antiapoptotic properties. Furthermore, HCB decreased the severity of pathological changes and significantly preserved the myocardial creatinine phosphokinase confirming its myocardial salvaging effects. Results clearly demonstrated the therapeutic potential of the herbal drugs in the treatment of myocardial ischemia and reperfusion injury. If the beneficial effects can be established in-patients, these findings may represent a novel adjunctive therapy of ischemic heart disease and Myocardial Infarction.

Molecular Basis for the Cardioprotective Effect of Herbal Drugs in Ischemic Heart Disease: An Experimental Study

Present study evaluated the cardioprotective potential of hydroalcoholic extract of Withania somnifera (Ws) and Ocimum sanctum (Os) against isoproterenol (ISO) induced myocardial infarction in rats. Rats were administered different doses viz,Ws (50, 100 and 200 mg/kg) and Os (25, 50, 75, 100, 200 and 400mg/kg) orally using intragastric tube for two weeks. ISO-200 was administered to produce oxidative stress reflected in significant (p < 0.05) GSH and LDH depletion from the myocardial tissue. Myocardial necrosis was determined directly by staining with triphenyl tetrazolium chloride (TTC) and by histopatho-logical examination, which depicted clear focal myonecrosis with myophagocytosis and lymphocytic infiltration (myocarditis) and presence of marked inflammatory cells. Further biochemical studies also confirmed the presence of myocardial necrosis.