Showing papers by "Annamalai University published in 2003"

Physico-chemical characteristics of the Vellar estuary in relation to shrimp farming.

Abstract: All the physico-chemical parameters such as temperature, LEC, salinity, pH, dissolved oxygen and nutrients like total phosphorus, inorganic phosphate, nitrite and silicate studied in relation to shrimp farming There are as many as 42 shrimp farms situated on the banks of Vellar estuary These farms discharge the used water into the estuary, which may influence the biota there In the present study the physico-chemical feature in relation to shrimp farming were studied in 3 stations of the estuary When compared with the previous data from Vellar estuary there was no much difference in physico-chemical characteristics due to shrimp farming

Polythene and Plastics-degrading microbes from the mangrove soil

Abstract: Biodegradation of polythene bags and plastic cups was analyzed after 2, 4, 6, and 9 months of incubation in the mangrove soil. The biodegradation of polythene bags was significantly higher (up to 4.21% in 9 months) than that of plastic cups (up to 0.25% in 9 months). Microbial counts in the degrading materials were recorded up to 79.67 x 10(4) per gram for total heterotrophic bacteria, and up to 55.33 x 10(2) per gram for fungi. The microbial species found associated with the degrading materials were identified as five Gram positive and two Gram negative bacteria, and eight fungal species of Aspergillus. The species that were predominant were Streptococcus, Staphylococcus, Micrococcus (Gram +ve), Moraxella, and Pseudomonas (Gram -ve) and two species of fungi (Aspergillus glaucus and A. niger). Efficacy of the microbial species in degradation of plastics and polythene was analyzed in shaker cultures. Among the bacteria, Pseudomonas species degraded 20.54% of polythene and 8.16% of plastics in one-month period. Among the fungal species, Aspergillus glaucus degraded 28.80% of polythene and 7.26% of plastics in one-month period. This work reveals that the mangrove soil is a good source of microbes capable of degrading polythene and plastics.

Protective effects of ferulic acid on hyperlipidemic diabetic rats

Abstract: Diabetes, when uncontrolled, causes dyslipidemia often followed by atherogenic abnormalities. The present study was focused to determine whether ferulic acid (FA), a flavonoid, has any role to play in diabetes-induced dyslipidemia. Diabetes in rats was induced with streptozotocin. The levels of blood glucose and plasma triglycerides (TG), free fatty acids (FFA), cholesterol and phospholipids were elevated during diabetes. Treatment with FA significantly reduced the elevated plasma lipid and blood glucose levels; a more pronounced effect was found with low-dose ferulic acid than with high dose. Thus, our study demonstrates that ferulic acid lowers the lipid levels in diabetic rats and hence prevents further complications.

Protective effect of fenugreek (Trigonella foenum graecum) seeds in experimental ethanol toxicity.

Abstract: The study investigates the effect of aqueous extract of fenugreek seeds (Trigonella foenum graecum) on lipid peroxidation and antioxidant status in experimental ethanol toxicity in rats. The ability of the seed extract to prevent iron-induced lipid peroxidation in vitro was also investigated. Ethanol feeding for 60 days resulted in significant increases in the activities of serum aspartate transaminase, alanine transaminase and alkaline phosphatase. The levels of serum lipid hydroperoxides and thiobarbituric acid reactive substances in liver and brain were also significantly elevated. Significantly lower activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione S-transferase and glutathione reductase were observed in liver and brain accompanied by depletion in glutathione, ascorbic acid and alpha-tocopherol concentrations. Activity of Ca(2+) ATPase in brain was significantly lowered. Simultaneous administration of aqueous extract of fenugreek seeds with ethanol prevented the enzymatic leakage and the rise in lipid peroxidation and enhanced the antioxidant potential. The seeds exhibited appreciable antioxidant property in vitro which was comparable with that of reduced glutathione and alpha-tocopherol. Further, histopathological examination of liver and brain revealed that, aqueous extract of fenugreek seeds could offer a significant protection against ethanol toxicity.

Activity of Cassia auriculata leaf extract in rats with alcoholic liver injury.

Abstract: This study was undertaken to investigate the effect of Cassia auriculata leaf extract on tissue lipid peroxidation and antioxidant status in experimental hepatotoxicity. Administering ethanol to rats for 60 days resulted in significantly elevated levels of serum total bilirubin, aspartate transaminase (AST), alanine transaminase (ALT) and alkaline phosphatase (ALP) as compared with those of the experimental control rats. Significantly elevated levels of tissue thiobarbituric acid reactive substances (TBARS), hydroperoxides and lowered activities of superoxide dismutase (SOD), catalase (CAT) and reduced glutathione (GSH) were also observed on alcohol treatment as compared with those of experimental control rats. Concentration of serum non-enzymic antioxidants such as vitamin E and vitamin C were also significantly lowered on alcohol supplementation. Treatment with Cassia auriculata leaf extract at a dose of 250 mg kg −1 body weight and 500 mg kg −1 body weight to rats administered alcohol, lowered the levels of TBARS and hydroperoxides and elevated the activities of SOD and CAT and the levels of reduced GSH in the liver, brain, kidney and intestine significantly compared to unsupplemented alcohol treated rats. Cassia auriculata leaf extract treatment restored the serum vitamin E, and vitamin C levels also to near those of the experimental control animals. Our data indicate that supplementation with Cassia auriculata leaf extract can offer protection against free radical mediated oxidative stress in experimental hepatotoxicity. In addition, histopathological studies of the liver and brain confirmed the beneficial role of Cassia auriculata leaf extract.

Preventive effects of Cassia auriculata L. flowers on brain lipid peroxidation in rats treated with streptozotocin

Abstract: The effect of aqueous extract of the flowers of Cassia auriculata were examined on antioxidants and lipid peroxidation in the brain of streptozotocin diabetic rats. Significant increase in the activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase and reduced glutathione were observed in brain on treatment with Cassia auriculata flower extract (CFEt) and glibenclamide. Both the treated groups showed significant decrease in thiobarbituric reactive substances (TBARS) and hydroperoxide formation in brain, suggesting its role in protection against lipid peroxidation induced membrane damage. Since the study of induction of the antioxidant enzymes is considered to be a reliable marker for evaluating the antiperoxidative efficacy of medicinal plant, these findings are suggestions of possible antiperoxidative role played by Cassia auriculata flower extract.

How do mangrove forests induce sedimentation

Abstract: The mangrove forests play a significant role as sediment traps. They reduce tidal flows and induce sedimentation of soil particles at low tide. However, there are no such processes taking place in the non-mangrove areas. Site of Avicennia–Rhizophora interphase is more efficient than Avicennia and or Rhizophora zones, in trapping the sediment by 30, 25 and 20% respectively at low tide as compared to high tide

Antioxidant action of Moringa oleifera Lam. (drumstick) against antitubercular drugs induced lipid peroxidation in rats.

Abstract: The protective effect of Moringa oleifera Lam. (Moringaceae) on hepatic marker enzymes, lipid peroxidation, and antioxidants was investigated during antitubercular drug (isoniazid, rifampicin, and pyrazinamide)-induced toxicity in rats. Enhanced hepatic marker enzymes and lipid peroxidation of antitubercular drug treatment was accompanied by a significant decrease in the levels of vitamin C, reduced glutathione, superoxide dismutase, catalase, glutathione peroxidase, and glutathione S-transferase. Administration of Moringa oleifera extract and silymarin significantly decreased hepatic marker enzymes and lipid peroxidation with a simultaneous increase in the level of antioxidants. We speculate that Moringa oleifera extract exerts its protective effects by decreasing liver lipid peroxides and enhancing antioxidants.

Antihyperglycaemic effect of Cassia auriculata in experimental diabetes and its effects on key metabolic enzymes involved in carbohydrate metabolism.

Abstract: 1. In experimental diabetes, enzymes of glucose and fatty acid metabolism are markedly altered. Persistent hyperglycaemia is a major contributor to such metabolic alterations, which lead to the pathogenesis of diabetic complications. To our knowledge, there are no available reports on the enzymes of hepatic glucose metabolism of Cassia auriculata flower against diabetes. The present study was designed to study the effect of Cassia auriculata flower extract (CFEt) on hepatic glycolytic and gluconeogenic enzymes. 2. Streptozotocin diabetic rats were given CFEt (0.15, 0.30 and 0.45 g/kg) or 600 microg/kg glibenclamide for 30 days. At the end of 30 days, blood glucose, plasma insulin, haemoglobin, glycosylated haemoglobin, glycolytic and gluconeogenic enzymes were assessed. 3. Administration of CFEt at 0.45 g/kg significantly decreased blood glucose, glycosylated haemoglobin and gluconeogenic enzymes and increased plasma insulin, haemoglobin and hexokinase activity. Similarly, administration of glibenclamide showed a significant effect; however, CFEt at 0.15 and 0.30 g/kg did not show any significant effect. 4. In conclusion, the observations show that the aqueous extract of CFEt possesses an antihyperglycaemic effect and suggest that enhanced gluconeogenesis during diabetes is shifted towards normal and that the extract enhances the utilization of glucose through increased glycolysis. The effect of CFEt was more prominent than that of glibenclamide.

Global pollution monitoring of PCBs and organochlorine pesticides using skipjack tuna as a bioindicator.

Abstract: Concentrations of organochlorines (OCs) representing persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs), dichlorodiphenyl trichloroethane and its metabolites (DDTs), chlordane compounds (CHLs), hexachlorocyclohexane isomers (HCHs), and hexachlorobenzene (HCB), were determined in the liver of skipjack tuna (Katsuwonus pelamis) collected from the offshore waters of various regions in the world (offshore waters around Japan, Taiwan, Philippines, Indonesia, Seychelles, and Brazil, and the Japan Sea, the East China Sea, the South China Sea, the Bay of Bengal, and the North Pacific Ocean). OCs were detected in livers of all of the skipjack tuna collected from the locations surveyed, supporting the thesis that there is widespread contamination of persistent OCs in the marine environment. Within a location, no significant relationship between growth-stage (body length and weight) and OC concentrations (lipid weight basis) was observed, and the OC residue levels were rather uniform among the individuals. Interestingly, the distribution of OC concentrations in skipjack tuna was similar to those in surface seawaters from which they were taken. These results suggest that OC concentrations in skipjack tuna could reflect the pollution levels in seawater from which they are collected and that this species is a suitable bioindicator for monitoring the global distribution of OCs in offshore waters and the open ocean. Concentrations of PCBs and CHLs in skipjack tuna were higher in offshore waters around Japan (up to 1100 and 250 ng/g lipid wt, respectively), suggesting the presence of sources of PCBs and CHLs in Japan. High concentrations of DDTs and HCHs were observed in samples from the Japan Sea, the East China Sea, the South China Sea, and the Bay of Bengal (up to 1300 and 22 ng/g lipid wt, respectively). This result suggests recent use of technical DDT and HCH for agricultural and/or public health purposes in Russia, China, India, and some other developing Asian countries. Relatively high concentrations of PCBs, CHLs, HCHs, and HCB were also observed in samples collected from some locations in the middle of the Pacific Ocean, indicating the expansion of OC contamination on a global scale. Considering these facts, continuous studies monitoring these compounds in offshore waters and the open seas, using skipjack tuna as a bioindicator, are needed to further understand the future trend of contamination.

Hypoglycaemic and hypolipidaemic action of alcohol extract of Tinospora cordifolia roots in chemical induced diabetes in rats.

Abstract: The present investigation was undertaken to evaluate the hypoglycaemic and hypolipidaemic effects of an alcohol extract of Tinospora cordifolia roots, an indigenous plant used in Ayurvedic medicine in India. Oral administration of the extract of Tinospora cordifolia (TCREt) roots for 6 weeks resulted in a significant reduction in blood and urine glucose and in lipids in serum and tissues in alloxan diabetic rats. The extract also prevented a decrease in body weight. Thus our study clearly shows that an alcohol TCREt has a hypoglycaemic and hypolipidaemic action.

Supplementation of fenugreek leaves to diabetic rats. Effect on carbohydrate metabolic enzymes in diabetic liver and kidney.

Abstract: The present study was designed to evaluate the effect of supplementation of fenugreek leaves, an indigenous plant widely used in Indian Ayurvedic medicine for the treatment of diabetes mellitus, in streptozotocin induced diabetic rats. Supplementation of the diet with fenugreek leaves showed a significant effect on hyperglycaemia, hypoinsulinaemia and glycosylated haemoglobin in streptozotocin diabetic rats. Fenugreek leaves improved the body weight and liver glycogen. Fenugreek leaves also showed a significant effect on key carbohydrate metabolic enzymes in diabetic rats. The effect of fenugreek leaves was found to be similar to that of glibenclamide. Thus, fenugreek leaves exhibited antidiabetic action in streptozotocin-induced diabetic rats. Insulin restored all the parameters to near normal levels in diabetic rats.

Antihyperglycemic activity of Eclipta alba leaf on alloxan-induced diabetic rats.

Abstract: Eclipta alba, an indigenous medicinal plant, has a folk (Siddha and Ayurvedha) reputation in rural southern India as a hypoglycemic agent. In order to confirm this claim, the present study was carried out to evaluate the antihyperglycemic effect of E. alba and to study the activities of liver hexokinase and gluconeogenic enzymes such as glucose-6-phosphatase and fructose 1,6-bisphosphatase in the liver of control and alloxan-diabetic rats. Oral administration of leaf suspension of E. alba (2 and 4 g/kg body weight) for 60 days resulted in significant reduction in blood glucose (from 372.0 +/- 33.2 to 117.0 +/- 22.8), glycosylated hemoglobin HbA(1)c, a decrease in the activities of glucose-6 phosphatase and fructose 1,6-bisphosphatase, and an increase in the activity of liver hexokinase. E. alba at dose of 2 g/kg body weight exhibited better sugar reduction than 4 g/kg body weight. Thus, the present study clearly shows that the oral administration of E. alba possess potent antihyperglycemic activity.

Protection of pancreatic beta-cell by the potential antioxidant bis-o-hydroxycinnamoyl methane, analogue of natural curcuminoid in experimental diabetes.

Abstract: PURPOSE. To evaluate the antioxidant defense by bis-o-hydroxycinnamoylmethane, analogue of the naturally occurring curcuminoid bis-demethox- ycurcumin in streptozotocin induced diabetes in male Wistar rats and its possible protection of pancreatic β- cell against gradual loss under diabetic condition. METHODS. Male wistar rats were divided into five groups. Group1 served as control rats. Group2 was control rats treated intragastrically with bis-o-hydroxy- cinnamoyl methane at a dose of 15mg/kg body weight for 45 days. Group3, 4 and 5 rats were injected with 40mg /kg body weight of streptozotocin to induce dia- betes. Group4 rats were treated with the drug similar to group2 and group5 rats treated with the reference drug glibenclamide intragastrically for a similar period. After 45 days, the levels of plasma glucose, glycated hemoglobin, enzymic antioxidants (SOD, CAT) and non-enzymic antioxidants Vit C, Vit E was deter- mined. Histopathological sections of the pancreas were examined. RESULTS. The levels of plasma glucose and glycated hemoglobin which were elevated in group3 diabetic rats were reduced after treatment with the drug. The antioxidant levels showed an increase in the case of treated diabetic rats as compared to group3 dia- betic rats. The islets were shrunken in group3 diabetic rats in comparison to normal rats. In the treated dia- betic rats there was expansion of islets. CONCLU- SIONS. The experimental drug bis-o- hydroxycinnamoylmethane enhances the antioxidant defense against reactive oxygen species produced under hyperglycemic conditions and thus protects the pan- creatic β-cell against loss and exhibits antidiabetic prop- erty.

Effect of Piper betle leaf extract on alcoholic toxicity in the rat brain.

Abstract: The protective effect of Piper betle, a commonly used masticatory, has been examined in the brain of ethanol-administered Wistar rats. Brain of ethanol-treated rats exhibited increased levels of lipids, lipid peroxidation, and disturbances in antioxidant defense. Subsequent to the experimental induction of toxicity (i.e., the initial period of 30 days), aqueous P. betle extract was simultaneously administered in three different doses (100, 200, and 300 mg kg-1) for 30 days along with the daily dose of alcohol. P. betle coadministration resulted in significant reduction of lipid levels (free fatty acids, cholesterol, and phospholipids) and lipid peroxidation markers such as thiobarbituric acid reactive substances and hydroperoxides. Further, antioxidants, like reduced glutathione, vitamin C, vitamin E, superoxide dismutase, catalase, and glutathione peroxidase, were increased in P. betle-coadministered rats. The higher dose of extract (300 mg kg-1) was more effective, and these results indicate the neuropr...

S-allylcysteine inhibits circulatory lipid peroxidation and promotes antioxidants in N-nitrosodiethylamine-induced carcinogenesis.

Abstract: Effects of S-allylcysteine (SAC), an organosulfur compound of garlic, on circulatory lipid peroxidation and antioxidant levels were evaluated in N-nitrosodiethylamine (NEDA)-induced hepatocarcinogenesis in Wistar rats. Significantly elevated thiobarbituric acid reactive substances in the circulation of rats bearing carcinoma indicated the higher levels of lipid peroxidation which was accompanied by significantly decreased levels of antioxidants (beta-carotene, ascorbic acid, alpha-tocopherol, reduced glutathione, glutathione peroxidase, superoxide dismutase and catalase) when compared with controls. Lipid peroxidation has been implicated as a major cause in cancer development. SAC-administered rats showed the inhibition of tumor incidence and lipid peroxidation with simultaneous elevation in antioxidants. We suggest that SAC exerts its chemopreventive effects by decreasing lipid peroxidation and enhancing the levels of antioxidants in NDEA carcinogenesis by reducing the formation of free radicals.

Effect of Aegle marmelos Correa. (Bael) fruit extract on tissue antioxidants in streptozotocin diabetic rats.

Abstract: A study was undertaken to evaluate the anti-lipid peroxidative activity of an aqueous extract of A. marmelos fruits (AMFEt) in streptozotocin diabetic rats in heart and pancreas. Oral administration of AMFEt for 30 days (125 and 250 mg kg(-1) body weight twice daily) produced a significant decrease in the elevated levels of peroxidation products, viz. thiobarbituric acid reactive substances and hydroperoxides in the tissues of diabetic rats. The depressed activities of superoxide dismutase, catalase and glutathione peroxidase and lowered glutathione content in the heart and pancreas of diabetic rats were found to increase on treatment with AMFEt. AMFEt at a dose of 250 mg kg(-1) was more effective than glibenclamide (300 microg kg(-1)) and both reversed all the values significantly. Thus AMFEt exhibits anti-oxidative activity in streptozotocin diabetic rats.

Protective Effect of Sesbania grandiflora Against Erythromycin Estolate-Induced Hepatotoxicity

Abstract: Sesbania grandiflora, commonly known as 'sesbania', is widely used in Indian folk medicine for the treatment of liver disorders. Oral administration of an ethanolic extract of S. grandiflora leaves (200 mg/kg/day) for 15 days produced significant hepatoprotection against erythromycin estolate (800 mg/kg/day)-induced hepatotoxicity in rats. The increased level of serum enzymes (aspartate transaminase, alanine transaminase, alkaline phosphatase), bilirubin, cholesterol, triglycerides, phospholipids, free fatty acids, plasma thiobarbituric acid reactive substances and hydroperoxides observed in rats treated with erythromycin estolate were significantly decreased in rats treated concomitantly with sesbania extract and erythromycin estolate. The sesbania extract also restored the depressed levels of antioxidants to near normal. The results of the study reveal that sesbania could afford a significant protective effect against erythromycin estolate-induced hepatotoxicity. The effect of sesbania was compared with that of silymarin, a reference hepatoprotective drug.

Protective effects of curcumin and photo-irradiated curcumin on circulatory lipids and lipid peroxidation products in alcohol and polyunsaturated fatty acid-induced toxicity

Abstract: Alcohol is a neurotoxin associated with significant morbidity and mortality. Ethanol is found to induce a dose dependent increase in lipid peroxidation (LPO). The elevation in lipid peroxidative products and the loss of antioxidant defense potential are enhanced when alcohol is taken along with polyunsaturated fatty acid (PUFA) or heated PUFA. The present study was undertaken to evaluate the effects of curcumin and photo-irradiated curcumin on alcohol and PUFA induced LPO and lipid profiles in plasma. The levels of vitamin C and E were decreased significantly in alcohol + raw as well as heated PUFA groups. The treatment with curcumin and photo-irradiated curcumin (IC) increased their levels significantly. The increase was more significant in the IC group than the curcumin group. The levels of cholesterol, phospholipids (PL), triglycerides (TG), free fatty acids (FFA), thiobarbituric acid reactive substances (TBARS) and hydroperoxides (HP) were increased significantly in alcohol + raw as well as heated PUFA groups and the treatment with curcumin and IC, brought back the levels. But the IC reduced the levels more significantly than curcumin. Thus, our results indicate that IC is a more potent antioxidant than curcumin. Copyright © 2003 John Wiley & Sons, Ltd.

Effect of Aegle marmelos fruits on normal and streptozotocin-diabetic Wistar rats.

Abstract: The present study evaluates the antidiabetic effect of an aqueous extract of Aegle marmelos fruits (AMFEt) in diabetes. Female albino Wistar rats were randomly divided into five groups: normal (untreated), normal + AMFEt, streptozotocin (STZ)-treated, STZ-treated + AMFEt, and STZ-treated + glibenclamide. Rats were rendered diabetic by STZ (45 mg/kg) administered intraperitoneally. AMFEt (250 mg/kg) was given twice daily for 1 month. Blood glucose, plasma insulin, glycosylated hemoglobin, liver glycogen, and change in body weight were determined. Food intake and water intake were monitored daily. An oral glucose tolerance test was also performed to determine the effect of this extract. The results show that glucose level and glycosylated hemoglobin were increased and plasma insulin and liver glycogen were decreased in diabetic rats, and that treatment with AMFEt reversed the effects of diabetes on these biochemical parameters to near-normal levels.

Mutation analysis of the cathepsin C gene in Indian families with Papillon-Lefèvre syndrome

Abstract: PLS is a rare autosomal recessive disorder characterized by early onset periodontopathia and palmar plantar keratosis. PLS is caused by mutations in the cathepsin C (CTSC) gene. Dipeptidyl-peptidase I encoded by the CTSC gene removes dipeptides from the amino-terminus of protein substrates and mainly plays an immune and inflammatory role. Several mutations have been reported in this gene in patients from several ethnic groups. We report here mutation analysis of the CTSC gene in three Indian families with PLS. Peripheral blood samples were obtained from individuals belonging to three Indian families with PLS for genomic DNA isolation. Exon-specific intronic primers were used to amplify DNA samples from individuals. PCR products were subsequently sequenced to detect mutations. PCR-SCCP and ASOH analyses were used to determine if mutations were present in normal control individuals. All patients from three families had a classic PLS phenotype, which included palmoplantar keratosis and early-onset severe periodontitis. Sequence analysis of the CTSC gene showed three novel nonsense mutations (viz., p.Q49X, p.Q69X and p.Y304X) in homozygous state in affected individuals from these Indian families. This study reported three novel nonsense mutations in three Indian families. These novel nonsense mutations are predicted to produce truncated dipeptidyl-peptidase I causing PLS phenotype in these families. A review of the literature along with three novel mutations reported here showed that the total number of mutations in the CTSC gene described to date is 41 with 17 mutations being located in exon 7.