C. S. Shyamala Devi

Antitumor, anti-inflammatory and analgesic property of embelin, a plant product

Embelin, a plant-based benzoquinone derivative, has been found to exhibit significant antitumor activity in methylcholanthrene-induced fibrosarcoma in albino rats besides enhancing their survival time. The drug also has an appreciable action on pain and inflammation. The changes in DNA, RNA and protein levels in various organs in the tumor-bearing control and the drug-treated animals were also studied.

Antibacterial activity of embelin.

Embelin, a benzoquinone-derivative isolated from Embelia ribes, when tested for its antibacterial potential exhibited significant inhibition against five and moderate activity against three strains of the 12 bacteria tested.

Cigarette smoking induces heat shock protein 70 kDa expression and apoptosis in rat brain: Modulation by bacoside A

Cigarette smoking is associated with the development of several diseases and antioxidants play a major role in the prevention of smoking-related diseases. Apoptosis is suggested as a possible contributing factor in the pathogenesis of smoking-induced toxicity. Therefore the present study was designed to investigate the influence of chronic cigarette smoke exposure on apoptosis and the modulatory effect of bacoside A (triterpenoid saponin isolated from the plant Bacopa monniera) on smoking-induced apoptosis in rat brain. Adult male albino rats of Wistar strain were exposed to cigarette smoke and simultaneously administered with bacoside A (10 mg/kg b.w./day, orally) for a period of 12 weeks. Expression of brain hsp70 was analyzed by Western blotting. Apoptosis was identified by DNA fragmentation, terminal deoxynucleotidyl transferase-mediated deoxy uridine triphosphate nick end labeling (TUNEL) staining and transmission electron microscopy. The results showed that exposure to cigarette smoke induced hsp70 expression and apoptosis as characterized by DNA laddering, increased TUNEL-positive cells and ultrastructural apoptotic features in the brain. Administration of bacoside A prevented expression of hsp70 and neuronal apoptosis during cigarette smoking. We speculate that apoptosis may be responsible for the smoking-induced brain damage and bacoside A can protect the brain from the toxic effects of cigarette smoking.

Biochemical and molecular properties of lithium-sensitive myo-inositol monophosphatase

Myo-inositol monophosphatase is a pivotal enzyme of the inositol second messenger system which is specifically inhibited by therapeutic levels of lithium salts, implicating inhibition of this enzyme as a potential site of its action in bipolar disease. This enzyme has a native molecular weight of 59,000, and has traditionally been found in the cytosolic fraction, although a membrane-bound form has also been identified. Possessing two identical subunits, this enzyme hydrolyzes those monophosphates which are equatorially located within the inositol ring, and several nucleoside monophosphates phosphorylated at the 2-position. Each subunit of the native enzyme contains an active site with unusually large caverns as revealed by crystallographic studies, which may explain the accommodation of these structurally unrelated substrates. We have suggested that the uncompetitive inhibition of this phosphatase by lithium ions may prevent the formation of an enzyme-bound non-isomeric (meso) intermediate, Mg(2+)-inositol 1,3 or 4,6 cyclic monophosphate when this enzyme hydrolyzes its respective isomeric substrates.

Effects of radiation and α-tocopherol on saliva flow rate, amylase activity, total protein and electrolyte levels in oral cavity cancer

OBJECTIVE The objective of the present study was to evaluate early and late effects of radiation and a-tocopherol on the secretion rate of saliva and on selected saliva salivary parameters in oral cavity cancer patients. PATIENTS & METHODS Eighty-nine histologically confirmed oral cavity cancer patients (OCC) were enrolled in the study. Resting whole saliva was collected before, during and at the end of the radiation therapy (RT) and simultaneous supplementation with alpha - tocopherol to the radiation treated patients (RT + AT). RESULTS Salivary flow rate, pH, amylase activity, total protein, sodium and potassium were analyzed. Increased pH, potassium and decreased flow rate, amylase activity, protein content and sodium were observed in 6 weeks of radiation treated patients when compared to OCC patients. A significant improvement of those parameters was observed on alpha - tocopherol supplementation in RT + AT patients. CONCLUSION Supplementation with alpha - tocopherol improves the salivary flow rate thereby, maintains salivary parameters.

Antioxidant effect of methanolic extract ofSolanum nigrum berries on aspirin induced gastric mucosal injury.

The antiulcerogenic effects of the methanolic extract ofSolanum nigrum berries (SBE) on aspirin induced ulceration in rats with respect to antioxidant status in the gastric mucosa have been investigated. Oxygen free radicals are considered to be important factors in the pathogenesis of gastric ulcer. The level of lipid peroxides, which were elevated highly in rats with acute gastric mucosal injury was taken as an index of oxidative stress. The activities of antioxidant defense enzymes were also decreased considerably by oral gastric administration of aspirin. The decreased levels of antioxidant enzymes and increased mucosal injury were altered to near normal status upon pretreatment with (SBE) when compared to the ulcer induced rats. The results indicate that (SBE) may exert its gastroprotective effect by a free radical scavenging action. Our observations suggest that (SBE) may have considerable therapeutic potential in the treatment of gastric diseases.

Effect of arogh—A polyherbal formulation on the marker enzymes in isoproterenol induced myocardial injury

To study the protective role of Arogh on isoproterenol induced myocardial damage in rats. The effect of Arogh pretreatment on isoproterenol induced myocardial damage was assessed by studying the levels of lipid peroxides and changes in the activity of marker enzymes such as creatine kinase, lactate dehydrogenase and transaminases in serum and heart tissue. In isoproterenol administered rats, a significant decrease was observed in the activity of marker enzymes in the heart with a corresponding increase in their levels in serum. Lipid peroxide levels increased significantly in the serum and heart. In rats pretreated with arogh, the level of lipid peroxides and the activity of marker enzymes were maintained at near normal values. Pretreatment with Arogh offered a protective effect against isoproterenol induced myocardial damage in rats as evidenced by LDH isoenzyme patterm and histopathological studies of heart tissue.

Mechanism of protective action of mangiferin on suppression of inflammatory response and lysosomal instability in rat model of myocardial infarction.

Lysosomal instability has been suggested as a major factor in the development of cellular injury during myocardial necrosis through the formation of inflammatory mediators. The present study was designed to investigate the effect of mangiferin on lysosomal hydrolases and TNF‐α production during isoproterenol (ISPH) induced myocardial necrosis in rats. The rats given ISPH (200 mg/kg body weight twice, subcutaneous) for 2 days showed a significant increase in plasma TNF‐α production, serum and heart lysosomal hydrolases activity. ISPH administration to rats resulted in decreased stability of the membranes, which was reflected by the lowered activity of cathepsin‐D and β‐glucuronidase in mitochondrial, nuclear, lysosomal and microsomal fractions. Pretreatment with mangiferin (100 mg/kg body weight, intraperitoneally) for 28 days, significantly prevented the alterations and restored the enzyme activities to near‐normal status. These findings demonstrate that mangiferin could preserve lysosomal integrity through decrease in the inflammatory process and hence establish the cardioprotective effect of mangiferin. Copyright

Chemoprotective Effect of Sobatum against Lithium-Induced Oxidative Damage in Rats

Lithium therapy mainly used in curing some psychiatric diseases responsible for numerous undesirable side effects on different organs in humans. The present study explores the beneficial effect of sobatum, a purified compound of Solanum trilobatum, on lithium carbonate (Li2CO3)-induced multiple organ toxicity in rats. Li2CO3 (150 mg/kg body weight) was administered orally in drinking water for a period of 30 days to induce toxicity in rats. Li2CO3 could induce lipid peroxidation to a significant extent that was accompanied by marked reduction in reduced glutathione, SOD, CAT, GST, GPX activities, and parallel decline in ATP in tissues. Toxicity resulted in abnormal elevation of lipids such as cholesterol, triglycerides, phospholipids, and fatty acids in liver tissues. Treatment with sobatum affords substantial protection in liver and heart by altering all the parameters to near normal levels that were further confirmed by histological examination. Sobatum prevents Li2CO3-induced oxidative damage of DNA by reducing DNA fragmentation indicating its block on cell death. However, these results demonstrated that sobatum has the ability to suppress the drug-induced toxicity.

BACOPA MONNIERA Extract Induces Apoptosis in Murine Sarcoma Cells (S-180)

The Ayurvedic system of medicine recommends Bacopa monniera (BM) in the treatment of tumors. The present study aims to determine the mode of cell death induced by the ethanolic extract of BM in mouse S‐180 cells. BM‐treated S‐180 cells were assessed for cell viability in a dose‐ and time‐dependent manner using dye exclusion studies. Morphological changes in the BM‐treated and untreated cells were studied by transmission electron microscopy (TEM). Glutathione (GSH) levels were quantified and the percentage of apoptotic cells was determined using Annexin V‐FITC assay. The results indicate that BM induces a dose‐ and time‐dependent loss of cell viability with maximum cytotoxicity at 48 h at a concentration of 550 µg/ml. TEM studies indicate apoptosis in the BM‐treated cells. GSH levels were decreased in the BM‐treated cells and Annexin V‐FITC assay revealed 90.2% of the cells as apoptotic. Conclusively, BM induces cell death by apoptosis in S‐180 cells. Copyright