Annamalai University

About: Annamalai University is a education organization based out in Chidambaram, Tamil Nadu, India. It is known for research contribution in the topics: Lipid peroxidation & Antioxidant. The organization has 8098 authors who have published 10758 publications receiving 203872 citations.

Melatonin abrogates cadmium induced oxidative stress related neurotoxicity in rats.

Abstract: Background: Cadmium is a potent neurotoxic heavy metal, which induces oxidative stress and membrane disturbances in brain. Melatonin is an effective antioxidant and free radical scavenger against oxidative stress. The present study was designed to investigate the neuroprotective efficacy of melatonin in pro- tecting the Cd induced changes in the activity of acetylcholinesterase (AChE), levels of lipid per- oxidation, protein carbonyls, non-enzymatic an- tioxidant, enzymatic antioxidant status, mem- brane bound ATPases and histopathology in the brain of rats. Materials and Methods: Twenty four male albino rats were used. Cadmium induced oxida- tive neurotoxicity was induced by oral adminis- tration of Cd for four weeks. Melatonin was pre- treated along with Cd for four weeks to assess its neuroprotective activity against Cd intoxica- tion. Rats treated with vehicles alone were used as controls. Results: Rats intoxicated with cadmium (5 mg/kg/day) for 4 weeks significantly (p<0.05) reduced the AChE levels in the plasma and brain, elevated the levels of thiobarbituric acid reactive substances (TBARS), lipid hydroper- oxides and protein carbonyls along with the significant (p<0.05) decrease in the levels of non-enzymatic antioxidants (GSH, TSH and vit- amins C and E), enzymatic antioxidants super- oxide dismutase (SOD), catalase (CAT), glu- tathione peroxidase (GPx), glutathione S-trans- ferase (GST) and membrane bound ATPases in the brain tissue. Administration of melatonin (10 mg/kg/day) for 4 weeks in cadmium intoxi- cated rats significantly (p<0.05) diminished the levels of oxidative stress markers, lipid peroxi- dation and protein carbonyls in brain and sig- nificantly (p<0.05) elevated the levels of non- enzymatic and enzymatic antioxidants, brain and the activities of AChE, enzymatic antioxi- dants and ATPases in brain. The histopatho- logical studies in the brain of rats also sup- ported that melatonin markedly reduced the Cd induced pathological changes and preserved the normal histological architecture of the brain tissue. Conclusions: The results of the present study suggest that melatonin may be beneficial in combating the cadmium induced oxidative neu- rotoxicity in the brain of rats.

Syringic acid, a novel natural phenolic acid, normalizes hyperglycemia with special reference to glycoprotein components in experimental diabetic rats

Abstract: Objective To evaluate the antidiabetic effect of syringic acid, a natural phenolic compound on the levels of glycoprotein components in plasma and tissues of alloxan induced diabetic rats. Methods Diabetes was induced in male Wistar rats by a single intraperitoneal injection of alloxan (150 mg/kg b.w). Syringic acid (50 mg/kg b.w) was administered orally for 30 d. The effects of syringic acid on plasma glucose, insulin, C-peptide, plasma and tissue glycoproteins were studied. Results Oral administration of syringic acid (50 mg/kg b.w) for 30 d positively modulates the glycemic status in alloxan induced diabetic rats. The levels of plasma glucose were decreased with significant increase of plasma insulin and C-peptide level. The altered levels of plasma and tissue glycoprotein components were restored to near normal. No significant changes were noticed in normal rats treated with syringic acid. Conclusions The present findings suggest that syringic acid can potentially ameliorate glycoprotein components abnormalities in addition to its antidiabetic effect in experimental diabetes, further clinical studies are required to evaluate the use of syringic acid as an effective therapeutic agent for the treatment of diabetes mellitus.

Adulticidal and repellent properties of indigenous plant extracts against Culex quinquefasciatus and Aedes aegypti (Diptera: Culicidae)

Abstract: Several diseases are associated to the mosquito–human interaction. Mosquitoes are the carriers of severe and well-known illnesses such as malaria, arboviral encephalitis, dengue fever, chikunguniya fever, West Nile virus, and yellow fever. These diseases produce significant morbidity and mortality in humans and livestock around the world. The adulticidal and repellent activities of crude hexane, ethyl acetate, benzene, chloroform, and methanol extracts of leaf of Eclipta alba and Andrographis paniculata were assayed for their toxicity against two important vector mosquitoes, viz., Culex quinquefasciatus and Aedes aegypti (Diptera: Culicidae). The adult mortality was observed after 24 h of exposure. All extracts showed moderate adulticide effects; however, the highest adult mortality was found in methanol extract of A. paniculata against the adults of C. quinquefasciatus and A. aegypti with the LC50 and LC90 values were 149.81, 172.37 ppm and 288.12, 321.01 ppm, respectively. The results of the repellent activity of hexane, ethyl acetate, benzene, chloroform, and methanol extract of E. alba and A. paniculata plants at three different concentrations of 1.0, 2.5, and 5.0 mg/cm2 were applied on skin of forearm in man and exposed against adult female mosquitoes. In this observation, these two plant crude extracts gave protection against mosquito bites without any allergic reaction to the test person, and also, the repellent activity is dependent on the strength of the plant extracts. These results suggest that the leaf solvent plant extracts have the potential to be used as an ideal ecofriendly approach for the control of mosquitoes. This is the first report on the mosquito adulticidal and repellent activities of the reported E. alba and A. paniculata plants.

Intramolecular charge transfer associated with hydrogen bonding effects on 2-aminobenzoic acid

Abstract: Effect of solvents, buffer solutions of different pH and β-cyclodextrin (β-CD) on the absorption and fluorescence spectra of 2-aminobenzoic acid (2ABA) have been investigated. The inclusion complex of 2ABA with β-CD is discussed by semiempirical quantum calculations (AM1), absorption, emission, FT-IR, 1H NMR and scanning electron microscope (SEM). The Stokes shifts in 2ABA is correlated with different polarity scales suggest that 2ABA molecule is more polar in the S1 state. The increase in the excited state dipole moment values and β-CD studies confirm that the presence of intramolecular charge transfer (ICT) in 2ABA. Acidity constants for different prototropic equilibria of 2ABA in the S0 and S1 states are calculated. β-CD studies shows that (i) at pH ∼ 1, 2ABA forms 1:1 inclusion complex with β-CD, whereas at pH ∼ 7, it forms mixture of 1:1 and 1:2 inclusion complex and (ii) at pH ∼ 1, appearance of dual luminescence in higher β-CD solutions indicates carboxyl and amino groups present in the hydrophobic part of the β-CD. A mechanism is proposed to explain the inclusion process.