Showing papers by "Annamalai University published in 2005"

Coastal mangrove forests mitigated tsunami

Abstract: A study conducted after the 26th of December 2004 tsunami in 18 coastal hamlets along the south-east coast of India reiterates the importance of coastal mangrove vegetations and location characteristics of human inhabitation to protect lives and wealth from the fury of tsunami. The tsunami caused human death and loss of wealth and these decreased with the area of coastal vegetation, distance and elevation of human inhabitation from the sea. Human inhabitation should be encouraged more than 1 km from the shoreline in elevated places, behind dense mangroves and or other coastal vegetation. Some plant species, suitable to grow in between human inhabitation and the sea for coastal protection, are suggested.

Medicinal Properties of Neem Leaves: A Review

Abstract: Azadirachta indica, commonly known as neem, has attracted worldwide prominence in recent years, owing to its wide range of medicinal properties. Neem has been extensively used in Ayurveda, Unani and Homoeopathic medicine and has become a cynosure of modern medicine. Neem elaborates a vast array of biologically active compounds that are chemically diverse and structurally complex. More than 140 compounds have been isolated from different parts of neem. All parts of the neem tree- leaves, flowers, seeds, fruits, roots and bark have been used traditionally for the treatment of inflammation, infections, fever, skin diseases and dental disorders. The medicinal utilities have been described especially for neem leaf. Neem leaf and its constituents have been demonstrated to exhibit immunomodulatory, anti-inflammatory, antihyperglycaemic, antiulcer, antimalarial, antifungal, antibacterial, antiviral, antioxidant, antimutagenic and anticarcinogenic properties. This review summarises the wide range of pharmacological activities of neem leaf.

Lipid peroxidation and antioxidant status in patients with periodontitis.

Abstract: Our aim was to assess the degree of oxidative stress in patients with periodontitis by measuring their levels of thiobarbituric acid reactive substances (TBARS), enzymatic antioxidants (superoxide dismutase (SOD), catalase (CAT), glutathione peroxide (GSHPx)), and non-enzymatic antioxidants (vitamins E and C, reduced glutathione (GSH)). This study was conducted on 25 adult chronic periodontitis sufferers who were patients in Rajah Muthiah Dental College and Hospital, Annamalai University. The levels of TBARS and non-enzymatic antioxidants, and the activities of enzymatic antioxidants in the patients' plasma, erythrocytes and gingival tissues were assayed using specific colorimetric methods. The periodontitis sufferers had a significantly higher TBARS level than the healthy subjects. In the plasma, erythrocytes, erythrocyte membranes and gingival tissues of the periodontitis sufferers, enzymatic antioxidant activities were found to be significantly higher, whereas the levels of non-enzymatic antioxidants were significantly lower (except for reduced glutathione in the gingival tissues) relative to the parameters found for healthy subjects. The disturbance in the endogenous antioxidant defense system due to over-production of lipid peroxidation products at inflammatory sites can be related to a higher level of oxidative stress in patients with periodontitis.

Lycopene: a review of its potential as an anticancer agent.

Abstract: Dietary chemoprevention has emerged as a cost effective approach to control most prevalent chronic diseases including cancer. In particular, tomato and tomato products are recognised to confer a wide range of health benefits. Epidemiological studies have provided evidence that high consumption of tomatoes effectively lowers the risk of reactive oxygen species (ROS)-mediated diseases such as cardiovascular disease and cancer by improving the antioxidant capacity. Tomatoes are rich sources of lycopene, an antioxidant carotenoid reported to be a more stable and potent singlet oxygen quenching agent compared to other carotenoids. In addition to its antioxidant properties, lycopene shows an array of biological effects including cardioprotective, anti-inflammatory, antimutagenic and anticarcinogenic activities. The anticancer activity of lycopene has been demonstrated both in in vitro and in vivo tumour models. The mechanisms underlying the inhibitory effects of lycopene on carcinogenesis could involve ROS scavenging, upregulation of detoxification systems, interference with cell proliferation, induction of gap-junctional communication, inhibition of cell cycle progression and modulation of signal transduction pathways. This review outlines the sources, structure, absorption, metabolism, bioavailability and pharmacological properties of lycopene with special reference to its antioxidant and anticarcinogenic effects.

Protective role of tetrahydrocurcumin (THC) an active principle of turmeric on chloroquine induced hepatotoxicity in rats.

Abstract: PURPOSE. Tetrahydrocurcumin (THC) is an antioxidative substance, which is derived from cur- cumin, the component of turmeric. In the present investigation, the effect of THC and curcumin against chloroquine (CQ) induced hepatotoxicity were studied in female Wistar rats. METHODS On single oral administration of CQ (970 mg/kg body weight) the activities of serum marker enzymes namely aspartate transaminase, alanine transaminase and alkaline phos- phatase and the levels of bilirubin were significantly increased with significant alterations of lipids in serum and lipidperoxidation markers such as thiobarbituric acid reactive substances (TBARS) and hydroperoxides in plasma and liver were also elevated in CQ treated rats. The levels of non-enzymic antioxidants (vitamin C, vitamin E and reduced glutathione) and enzymic antioxidants (superoxide dismutase, catalase and glu- tathione peroxidase) were also decreased in CQ treated rats. Administration of THC (80 mg/kg body weight) and curcumin (80 mg/kg body weight) for 8 days before and 7 days after single administration of CQ sig- nificantly decreased the activities of serum markers and lipids in serum. In addition, the level of TBARS and hydroperoxides were significantly decreased with sig- nificant increase in non-enzymic and enzymic antioxi- dants on treatment with THC and curcumin. The biochemical observation was supplemented by histo- pathological examination of liver section. The results of the study reveal that THC shows more pronounced protective effect than curcumin against CQ induced toxicity.

Antihyperlipidemic and antiperoxidative effect of Diasulin, a polyherbal formulation in alloxan induced hyperglycemic rats.

Abstract: This study was undertaken to investigation the effect of Diasulin, a poly herbal drug composed of ethanolic extract of ten medicinal plants on blood glucose, plasma insulin, tissue lipid profile, and lipidperoxidation in alloxan induced diabetes. Ethanolic extract of Diasulin a, poly herbal drug was administered orally (200 mg/kg body weight) for 30 days. The different doses of Diasulin on blood glucose and plasma insulin in diabetic rats were studied and the levels of lipid peroxides [TBARS, and Hydroperoxide] and tissue lipids [cholesterol, triglyceride, phospholipides and free fatty acids] were also estimated in alloxan induced diabetic rats. The effects were compared with glibenclamide. Treatment with Diasulin and glibenclamide resulted in a significant reduction of blood glucose and increase in plasma insulin. Diasulin also resulted in a significant decrease in tissue lipids and lipid peroxide formation. The effect produced by Diasulin was comparable with that of glibenclamide. The decreased lipid peroxides and tissue lipids clearly showed the antihyperlipidemic and antiperoxidative effect of Diasulin apart from its antidiabetic effect.

Lipid peroxidation & antioxidants status in patients with oral squamous cell carcinoma.

Abstract: Background & objectives: Overproduction of lipid peroxidation byproducts and disturbances in antioxidant defense system have been implicated in the pathogenesis of several diseases including oral cancer. Though several studies have been done on the level of lipid peroxidation and antioxidants in oral cancer patients, there are no reports in patients with various clinical stages of oral squamous cell carcinoma. We carried out this study to assess the level of oxidative stress in oral cancer patients with various clinical stages. Methods: Blood samples of 48 adult male oral cancer patients with various clinical stages of oral cancer (stage II to stage IV, 16 of each) and 16 age and sex matched healthy subjects were collected. Plasma and erythrocytes levels of thiobarbituric acid reactive substances (TBARS), vitamin E, reduced glutathione (GSH), and activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) were assayed using specific colorimetric methods. The statistical comparisons were performed by one way analysis of variance (ANOVA) followed by Student’s t-test. Results: Elevated lipid peroxidation and decline in non-enzymatic and enzymatic antioxidants status were noticed in oral cancer patients as compared to healthy subjects. The TBARS levels were gradually increased whereas antioxidants were gradually reduced from stage II to stage IV of oral cancer patients. Interpretation & conclusion: The altered lipid peroxidation in plasma and erythrocytes of oral cancer patients may be related to their compensatory changes in the antioxidants defense system.

Antidiabetic effect of Scoparia dulcis: effect on lipid peroxidation in streptozotocin diabetes.

Abstract: Oxidative damage has been suggested to be a contributory factor in the development and complications of diabetes. The antioxidant effect of an aqueous extract of Scoparia dulcis, an indigenous plant used in Ayurvedic medicine in India was studied in rats with streptozotocin-induced diabetes. Oral administration of Scoparia dulcis plant extract (SPEt) (200 mg/kg body weight) for 3 weeks resulted in a significant reduction in blood glucose and an increase in plasma insulin. The aqueous extract also resulted in decreased free radical formation in tissues (liver and kidney) studied. The decrease in thiobarbituric acid reactive substances (TBARS) and hydroperoxides (HPX) and increase in the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH) and glutathione-S-transferase (GST) clearly show the antioxidant properties of SPEt in addition to its antidiabetic effect. The effect of SPEt at 200 mg/kg body weight was better than glibenclamide, a reference drug.

Ferulic acid, a natural protector against carbon tetrachloride‐induced toxicity

Abstract: The present work is aimed at evaluating the protective effect of ferulic acid (FA), a naturally occurring phenolic compound on CCl4 induced toxicity. The activities of liver markers (alanine transaminase, aspartate transaminase, alkaline phosphatase, gamma-glutamyl transferase), lipid peroxidative index (thiobarbituric acid-reactive substances, hydroperoxides, nitric oxide, protein carbonyl content), the antioxidant status (superoxide dismutase, catalase, glutathione peroxidase and reduced glutathione) were used as biomarkers to monitor the protective role of FA. The liver marker enzymes in plasma and lipid peroxidative index in liver and kidney were increased in CCl4-treated groups, which were decreased significantly on treatment with FA. The antioxidants, which were depleted in CCl4-treated groups, were improved significantly by FA treatment. Administration of FA to normal rats did not produce any harmful effects. Thus our results show that FA is an effective antioxidant without any side-effects and may be a great gain in the current search for natural therapy.

Effect of tetrahydrocurcumin on blood glucose, plasma insulin and hepatic key enzymes in streptozotocin induced diabetic rats

Abstract: The enzymes of glucose and lipid metabolism are markedly altered in experimental diabetes. In the present study, we investigated the effect of tetrahydrocurcumin (THC), one of the active metabolites in curcumin, on the key hepatic metabolic enzymes involved in carbohydrate metabolism in streptozotocin-induced diabetic rats. Different doses of THC (20, 40, and 80 mg\kg body weight) were orally administered to diabetic rats for 45 days. The activities of hexokinase, glucose-6-phosphate dehydrogenase (G6PD), glucose-6-phosphatase, fructose-1,6-bisphosphatase, and sorbitol dehydrogenase in liver, and glycogen content in liver and muscle were assayed. In untreated diabetic control rats, the activities of the gluconeogenic enzymes were significantly increased, whereas hexokinase and G6PD activity and glycogen levels were significantly decreased. Both THC and curcumin were able to restore the altered enzyme activities to near normal levels. Tetrahydrocurcumin was more effective than curcumin. Our results indicate that the administration of THC to diabetic animals normalizes blood glucose and causes a marked improvement of altered carbohydrate metabolic enzymes.

Effect of taurine on biomarkers of oxidative stress in tissues of fructose-fed insulin-resistant rats.

Abstract: Introduction The present study was designed to investigate whether taurine mitigates fructose-induced oxidative stress in rat tissues such as heart and kidney. Methods Male Wistar rats of body weight 170-190 g were divided into four groups containing six rats each. Control animals received the control diet containing starch while fructose-fed animals received a fructose-enriched diet (greater than 60 percent of total calories). Fructose and taurine rats received the fructose diet and two percent taurine solution to drink. Control and taurine rats received the control diet and two percent taurine solution. After the treatment period of 30 days, insulin resistance index, by homeostasis model assessment (HOMA) was determined. The levels of lipid peroxidation markers, the enzymatic and non-enzymatic antioxidants status in heart and kidney tissues were measured. Results Fructose rats showed high values of HOMA, increased lipid peroxidation and impaired antioxidant status. Taurine treatment to fructose rats attenuated the increased lipid peroxidation, enhanced the levels of antioxidants and improved insulin sensitivity. Conclusion Inhibition of peroxidation markers and upregulation of antioxidant activity in rat tissues by taurine signify the potential utility of taurine as an adjunct in treatment of insulin resistance.

Photocatalysis with ZrO2: oxidation of aniline

Abstract: ZrO 2 photocatalyzes the oxidation of aniline to azobenzene. The oxidation with natural sunlight and UV irradiation (365 nm) in ethanol was investigated as a function of [aniline], catalyst loading, airflow rate, solvent composition, etc. The photocatalyst exhibits sustainable catalytic activity. The product formation is larger with illumination at 254 nm than at 365 nm. Electron donors like triphenylphosphine, diphenylamine and hydroquinone enhance the photocatalysis. Singlet oxygen quencher, azide ion does not inhibit the catalysis. The photocatalysis occurs in protic as well as aprotic solvents. The mechanism of photocatalysis is discussed and the product formation examined using a kinetic model. TiO 2 , V 2 O 5 , ZnO, Fe 2 O 3 , CdO, CdS and Al 2 O 3 also photocatalyze the oxidation of aniline to azobenzene; with UV light of wavelength 254 nm ZrO 2 is more efficient than other photocatalysts studied, the photocatalytic activities are of the order ZrO 2 > ZnO > V 2 O 5 > Fe 2 O 3 > CdS > Al 2 O 3 > CdO > TiO 2 . However, ZrO 2 loses its edge over others on illumination at longer wavelength (365 nm) and with sunlight.

Oviposition deterrent and skin repellent activities of Solanum trilobatum leaf extract against the malarial vector Anopheles stephensi.

Abstract: The leaf extract of Solanum trilobatum (Solanaceae) was tested under laboratory conditions for oviposition deterrent and skin repellent activities against the adult mosquito Anopheles stephensi. Concentrations of 0.01, 0.025, 0.05, 0.075 and 0.1% reduced egg laying by gravid females from 18 to 99% compared to ethanol-treated controls. In skin repellent tests, concentrations of 0.001, 0.005, 0.01, 0.015, and 0.02 % provided 70 to 120 minutes protection against mosquito bites, whereas the ethanol control provided only 2.2 minutes of protection. Both oviposition deterrent and skin repellent activity were dose dependent. The results suggest that the leaf extract of S. trilobatum is an effective oviposition deterrent and skin repellent against An. stephensi.

Larvicidal effect of extracellular secondary metabolites of different fungi against the mosquito, Culex quinquefasciatus Say.

Abstract: The culture filtrates of five different soil fungi viz., Aspergillus flavus, Aspergillus parasiticus, Penicillium falicum, Fusarium vasinfectum and Trichoderma viride were tested for the larvicidal activity against third instar larvae of mosquito vector Culex quinquefasciatus. The concentrations of fungal culture filtrates used in the study ranged from 25 to 100 mg/L. The results showed that the larval mortality could be observed on 24 hours of exposure period. The LC5 0 values of A. flavus, A. parasiticus, P. falicum, F. vasinfectum and T. viride were 38.34, 40.39, 44.97, 50.03 and 54.16 mg/L, respectively. Among the five different fungi, the culture filtrates of A. flavus was found to be more toxic than the other four species of fungi against Cx. quinquefasciatus.

Comparative effects of Aegle marmelos extract and alpha-tocopherol on serum lipids, lipid peroxides and cardiac enzyme levels in rats with isoproterenol-induced myocardial infarction.

Abstract: Introduction We demonstrate the effect of Aegle marmelos leaf extract (AMLEt) and alpha-tocopherol on plasma lipids, lipid peroxides and marker enzymes in rats with isoproterenol (ISO)-induced myocardial infarction. Methods Rats were pre-treated orally for 35 days with different doses of an aqueous AMLEt (50 mg/ kg, 100 mg/kg and 200 mg/kg) prior to ISO-induced myocardial infarction. The effects on creatine kinase, lactate dehydrogenase, plasma thiobarbituric acid reactive substances, lipid hydroperoxides, serum lipids and lipoproteins were studied. Results Pre-treatment with AMLEt at doses of 100 mg/kg and 200 mg/kg bodyweight for 35 days showed a significant effect on the activities of marker enzymes, lipid peroxides, lipids, lipoproteins and antioxidant enzymes in ISO-treated rats. The effect of AMLEt 200 mg/kg was found to be equal to the effect of alpha-tocopherol 60 mg/kg. Conclusion Aegle marmelos leaves possess antihyperlipidaemic effect in rats with ISO-induced myocardial infarction.

Combination of S-allylcysteine and lycopene induces apoptosis by modulating Bcl-2, Bax, Bim and caspases during experimental gastric carcinogenesis

Abstract: Combination chemoprevention by diet-derived agents that induce apoptosis is a promising strategy to control gastric cancer, the second most common malignancy worldwide. The present study was undertaken to investigate the apoptosis-inducing potential of a combination of S-allylcysteine (SAC), an organosulphur constituent of garlic and lycopene, a tomato carotenoid during N-methyl-N'-nitro-N-nitroso-guanidine (MNNG) and saturated sodium chloride (S-NaCl)-induced gastric carcinogenesis in Wistar rats using the apoptosis-associated proteins Bcl-2, Bax, Bim, caspase 8 and caspase 3 as markers. Animals administered MNNG followed by S-NaCl developed squamous cell carcinomas of the stomach associated with increased Bcl-2 expression and decreased expression of Bax, Bim, caspase 8 and caspase 3. Although SAC and lycopene alone significantly suppressed the development of gastric cancer, administration of SAC and lycopene in combination was more effective in inhibiting MNNG-induced stomach tumours and modulating the expression of apoptosis-associated proteins. Our results suggest that induction of apoptosis by SAC and lycopene combination represents one of the possible mechanisms that could account for their synergistic chemopreventive activity against gastric cancer.

Prevalence pattern of dental caries in the primary dentition among school children

Abstract: The purpose of the study was to assess the pattern of prevalence of dental caries in the primary dentition among 5 year old children. The area of study was urban Pondicherry and the study population consisted of 1009 school children of both sexes (527 boys and 482 girls). A simple random sampling method was used to select the schools. Dental caries was assessed by the Dentition status and Treatment Need (WHO 1997). Statistical analysis was done using the Proportion test. The prevalence of caries was 44.4% among the study population, being higher in the boys (P < 0.05); In Mandibular arch in both the sexes (boys P < 0.05, girls P < 0.01); in posterior teeth (both sex wise & arch wise). Comparison of caries among anterior teeth (Boys vs Girls) [corrected] and posterior teeth (upper vs. lower) revealed higher caries prevalence in Maxillary anterior teeth (P < 0.001) and Mandibular posterior teeth (P < 0.001). In both the sexes and arches, primary second molars showed higher caries prevalence.

The effect of Aegle marmelos fruit extract in streptozotocin diabetes: a histopathological study.

Abstract: Aegle marmelos Correa. (Bael) fruit exhibit antidiabetic, antihyperlipidaemic and antioxidant properties. This study was designed to elucidate the protective effect of an aqueous extract of Aegle marmelos fruits on the histopathology of the pancreas in streptozotocin-induced diabetic rats. Oral administration of Aegle marmelos fruit extract at doses of 125 and 250 mg/kg twice daily to diabetic rats for a period of 30 days resulted in a significant increase in body weight, weight of the pancreas and insulin levels associated with a significant decrease in fasting blood glucose levels. The fruit extract treated groups showed improved functional state of the pancreatic ss-cells and partially reversed the damage caused by streptozotocin to the pancreatic islets. The findings of our study indicate that Aegle marmelos fruit extract exhibits protective effects on the pancreas. The effects observed in the fruit extract treated animals were better those in animals treated with glibenclamide (300 microg/kg).

Biosorption of zinc (II) by Rhizopus arrhizus: equilibrium and kinetic modelling

Abstract: The adsorption of zinc (II) ions on Rhizopus arrhizus , a filamentous fungus, was investigated in a batch reactor. Batch adsorption studies were carried out by varying biomass loading. A contact time of 120 min was required to reach equilibrium. Specific zinc (II) uptake decreased with increase in biomass loading and these results were analyzed in light of the Lagergren equation and the process followed a second order rate kinetics. The equilibrium data were analyzed using the Langmuir, Freundlich, Redlich- Peterson and BET adsorption isotherms. The characteristic parameters for each isotherm were determined. All the isotherms provided the best correlation for zinc (II) onto the R. arrhizus . African Journal of Biotechnology Vol. 4 (6), pp. 506-508, 2005

Antihyperlipidemic and antidiabetic effects of umbelliferone in streptozotocin diabetic rats.

Abstract: The aim of the study was to evaluate blood glucose and lipid lowering effects of Umbelliferone (UMB) in streptozotocin (STZ) diabetic rats. Male albino Wistar rats (180 to 200 g) were induced diabetes by administration of STZ (40 mg/kg) intraperitonially. Normal and diabetic rats were treated with UMB in 10 percent dimethyl sulfoxide (DMSO) for 45 days. Diabetic rats had increased plasma glucose and decreased insulin, total proteins (TP), and albumin in addition to decreased food intake and body weight. Elevation in total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), very low density lipoprotein cholesterol (VLDL-C), triglycerides (TG), free fatty acids (FFA), and phospholipids (PL), and reduction in high density lipoprotein cholesterol (HDL-C) in the plasma were observed. Liver and kidney tissues of diabetic rats had elevation in the levels of TC, TG, FFA, and PL. Treatment with UMB decreased plasma glucose and increased insulin, TP, and albumin apart from food intake and body weight. In UMB-treated diabetic rats, plasma and tissue TC, TG, PL and FFA, and plasma LDL-C, VLDL-C, and HDL-C reversed to near normal. Thus, reduction of blood glucose and lipid profiles indicates that UMB has antidiabetic and antihyperlipidemic effects in diabetic rats.