Identification of three novel myeloid cathelicidin cDNAs and their predicted peptides in buffalo (Bubalus bubalis).

Antimicrobial peptides (AMPs) are broad spectrum antibiotics, which mostly act without specific receptors. Identification of AMPs is important in the current scenario of emerging multi-drug resistant bacteria. In the present study, in an attempt to identify new AMPs, myeloid cathelicidin cDNAs were synthesized from buffalo (Bubalus bubalis) bone marrow and were amplified using specific primers. Sequence analysis of cloned cDNAs revealed three novel myeloid cathelicidins. They were named based on the number of active amino acids in the C-terminal region of their predicted peptide sequences as BuMAP-28 (having an additional Gly at position 22nd), BuMAP-29 (having an additional IIe at position 27) and BuMAP-34, compared to BMAP-27, BMAP-28 and BMAP-34 of cattle. The BuMAPs showed 93%, 95% and 87% homology respectively with that of its cattle counterpart. Predicted number of amino acids of the cDNAs was 159, 155 and 157 residues, with cationic C-terminal sequences of 28, 29 and 34, respectively, which correspond to putative antimicrobial domains. Several amino acid substitutions were observed in all the three cathelicidins. The conformation of the peptides was predicted to be alpha helical, having total net positive charge and hydrophobicity, similar to that of BMAPs in cattle. Comparative analysis of the predicted peptides suggested potential antimicrobial activity and the sequence variations detected might enable the peptides to act as effective broad spectrum antimicrobial agents.

Hypolipidaemic and antioxidant effects of fruits of Musa AAA (Chenkadali) in alloxan induced diabetic rats.

Hypolipidaemic and antioxidant effects of ethanol extract of mature green fruits of Musa AAA (Chenkadali) was evaluated in alloxan induced diabetic rats. The effect of extract at two doses, 500 mg/kg body weight and 1000 mg/kg body weight was analysed and compared with a standard drug, glibenclamide. Rats administered with alloxan showed significantly increased levels of serum triacylglycerol, total cholesterol and alanine amino transferase (ALT) activity. Lipid peroxides increased significantly while reduced glutathione (GSH) decreased considerably in liver and pancreas. Oral administration of the ethanol extract of fruits of Musa AAA (Chenkadali) significantly decreased the levels of serum triacylglycerol, cholesterol and ALT activity. Significant decrease was also observed in the level of lipid peroxides while GSH content increased substantially in liver and pancreas. The effect was dose independent and rats treated with 500 mg/kg body weight showed comparable levels of serum triacylglycerol, cholesterol, ALT activity and liver lipid peroxides to that of normal control and glibenclamide treated groups. Although, there was no significant difference, treatment with 500 mg/kg body weight of the extract showed a higher content of GSH and lower level of lipid peroxides in pancreas compared with glibenclamide. Histopathological examination of pancreas and liver revealed regeneration of islet cells and hepatocytes respectively, which correlate with the biochemical findings. The present study shows that ethanol extract of mature green fruits of Musa AAA (Chenkadali) has antioxidant and hypolipidaemic properties and may be used for treating diabetes mellitus.

Protective effect of Piper longum Linn. on monosodium glutamate induced oxidative stress in rats.

Protective effect of ethanol extract of Piper longum Linn. against monosodium glutamate (MSG) induced toxicity was studied. Rats, orally administered with MSG at a dose of 8 mg/g body weight for 20 consecutive days, showed an increase in liver weight and rate of lipid peroxidation. Glutathione (GSH) in serum, liver and kidney showed decreased concentration. Significant increase was noticed in activities of serum alanine amino transferase (ALT) and aspartate amino transferase (AST), levels of serum triacylglycerol, total cholesterol and urea. Histopathological examination of liver and kidney showed central venous congestion, diffuse degeneration and necrosis of hepatocytes in para cortical and midzonal areas of liver and diffuse cortical tubular degeneration of kidney. Oral administration of ethanol extract of P. longum fruits at 300 mg/kg body weight along with MSG significantly reduced the levels of lipid peroxides in serum, liver and kidney, serum AST activity, serum levels of triacylglycerol and total cholesterol. Though, there was an increase in the level of GSH in tissues it was not significant. However, the treatment failed to reduce the levels of ALT and urea. Examination of tissue sections also exhibited normal histological architecture of both the organs. The present study revealed that administration of P. longum provided significant protection to liver and kidney from the oxidative stress of MSG, though the dose rate was not sufficient to provide a complete protection.