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N Yadav

Publications and source records attributed to N Yadav.

12 recordsLinked to original sources
PubMed2006

Effect of Picroliv on cadmium-induced hepatic and renal damage in the rat.

The therapeutic efficacy of Picroliv--a standardized extract of Picrorhiza kurroa--was investigated in male rats exposed to CdCl2 (0.5 mg/kg, sc), 5 days/week for 18 weeks. Picroliv at two doses (6 and 12 mg/kg, po) was given to the cadmium (Cd)-administered group for the last 4 weeks (i.e., weeks 15-18). The Cd altered oxidative stress indices, such as increased lipid peroxidation and membrane fluidity, reduced levels of non-protein sulphydryls (NPSHs), and Na+K+ATPase activity in the liver and kidney were found close to the control values by Picroliv treatment, suggesting its antioxidant potential. The hepatoprotective action of Picroliv was evident by its ability to lower the Cd-induced liver function parameters--the serum enzymes, such as alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT) and lactate dehydrogenase (LDH). Bile flow and biliary Cd also increased as a result of Picroliv's choleretic property. The Cd-induced serum urea and urinary excretion of proteins, calcium (Ca), Cd and enzymes, such as N-acetyl-beta-D-glucosaminidase (NAG) and LDH, were less marked on Picroliv treatment, indicating recovery from nephrotoxicity. Organ uptake of Cd and essential metals by Cd exposure was reduced on Picroliv treatment. Cd-induced hepatic metallothionein (MT) was lowered by Picroliv, whereas renal MT was unaltered. Cd-induced hepatic damage was also minimized. However, the renal morphological changes were marginally protected by Picroliv. The 12-mg Picroliv dose was more effective than the 6-mg dose in causing amelioration of the above parameters. This study has provided clear evidence for the hepato- and renal protective efficacy of Picroliv against experimental Cd toxicity.

Animals↗
PubMed2005

Prevention of acute cadmium toxicity by Picroliv.

The potential of Picroliv, a herbal extract against acute cadmium (Cd) intoxication, was evaluated in male rats. Biochemical and histopathological profile in rats pretreated with Picroliv (12 mg/kg, oral) followed by a single dose of Cd as cadmium chloride (CdCl2) (3 mg/kg, ip) revealed marked suppression of oxidative stress in liver and testes. The Cd-induced enhanced levels of lipid peroxidation, membrane fluidity and reduced levels of nonprotein sulphydryls and Na(+)K(+)ATPase were significantly restored to near normal by Picroliv pretreatment. In addition, the Cd-induced serum levels of glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, gamma glutamyl transpeptidase and lactate dehydrogenase were restored to near basal levels. Hepatic and testicular histopathological damage was also minimized. The results strongly suggest definite hepato- and testicular protection by Picroliv. The antioxidant potential of the herbal extract in the major part, and not its chelating property, seems to be responsible for its ameliorative action.

Animals↗
PubMed2000

A novel protein kinase from Brassica juncea stimulated by a protozoan calcium binding protein. Purification and partial characterization.

A novel protein kinase (BjCCaBPk) from etiolated Brassica juncea seedlings has been purified and partially characterized. The purified enzyme migrated on SDS/PAGE as a single band with an apparent molecular mass of 43 kDa. The optimum pH for the kinase activity was 8.0. It was stimulated more than sixfold by the protozoa Entamoeba histolytica calcium binding protein EhCaBP (10.5 nM) but not by calmodulin (CaM) when used at equimolar concentration. Moreover the kinase also did not bind CaM-Sepharose. There was neither inhibition of the kinase activity in the presence of W-7 (a CaM antagonist), KN-62 (a specific calcium/CaM kinase inhibitor) and anti-CaM Ig, nor any effect on BjCCaBPk activity of staurosporine (a protein kinase C inhibitor). Furthermore a CaM-kinase specific substrate, syntide-2, proved to be a poor substrate for the BjCCaBPk compared with histone III-S. The phosphorylation of histone III-S involved serine residues. Southern and Northern blot analysis showed the presence of EhCaBP homologues in Brassica. The data suggest that BjCCaBPk may be a novel protein kinase with an affinity towards a calcium binding protein like EhCaBP.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1994

Arabidopsis FAD2 gene encodes the enzyme that is essential for polyunsaturated lipid synthesis.

The polyunsaturated fatty acids linoleate and alpha-linolenate are important membrane components and are the essential fatty acids of human nutrition. The major enzyme responsible for the synthesis of these compounds is the plant oleate desaturase of the endoplasmic reticulum, and its activity is controlled in Arabidopsis by the fatty acid desaturation 2 (fad2) locus. A fad2 allele was identified in a population of Arabidopsis in which mutations had been created by T-DNA insertions. Genomic DNA flanking the T-DNA was cloned by plasmid rescue and used to isolate cDNA and genomic clones of FAD2. A cDNA containing the entire FAD2 coding sequence was expressed in fad2 mutant plants and shown to complement the mutant fatty acid phenotype. The deduced amino acid sequence from the cDNA showed homology to other plant desaturases, and this confirmed that FAD2 is the structural gene for the desaturase. Gel blot analyses of FAD2 mRNA levels showed that the gene is expressed throughout the plant and suggest that transcript levels are in excess of the amount needed to account for oleate desaturation. Sequence analysis identified histidine-rich motifs that could contribute to an iron binding site in the cytoplasmic domain of the protein. Such a position would facilitate interaction between the desaturase and cytochrome b5, which is the direct source of electrons for the desaturation reaction, but would limit interaction of the active site with the fatty acyl substrate.

Alleles↗
PubMed1986

Single amino acid substitutions in the enzyme acetolactate synthase confer resistance to the herbicide sulfometuron methyl.

Sulfometuron methyl, a sulfonylurea herbicide, blocks growth of bacteria, yeast, and higher plants by inhibition of acetolactate synthase (EC 4.1.3.18), the first common enzyme in the biosynthesis of branched-chain amino acids. Spontaneous mutations that confer increased resistance to the herbicide were obtained in cloned genes for acetolactate synthase from Escherichia coli and Saccharomyces cerevisiae. The DNA sequence of a bacterial mutant gene and a yeast mutant gene revealed single nucleotide differences from their respective wild-type genes. The mutations result in single amino acid substitutions in the structurally homologous aminoterminal regions of the two proteins, but at different positions. The bacterial mutation results in reduced levels of acetolactate synthase activity, reduced sensitivity to sulfometuron methyl, and unaltered resistance to feedback inhibition by valine. The yeast mutation results in unaltered levels of acetolactate synthase activity, greatly reduced sensitivity to sulfometuron methyl, and slightly reduced sensitivity to valine.

Journal Article↗
PubMed1980

T-DNA from Agrobacterium Ti plasmid is in the nuclear DNA fraction of crown gall tumor cells.

The crown gall teratoma tumor line BT37, incited by Agrobacterium tumefaciens strain T37, has been found to contain part of the tumor-inducing plasmid, pTi T37, of the inciting strain. This foreign DNA segment, called T-DNA, is maintained at several copies per diploid tumor cell. We have examined subcellular DNA fractions from this tumor line in an effort to determine whether T-DNA is in chloroplasts, mitochondria, or nuclei. Tumor cell chloroplast DNA exhibited EcoRI and Bst I endonuclease cleavage patterns identical to those of normal tobacco chloroplast DNA. Tumor cell mitochondrial DNA exhibited a complex Bst I cleavage pattern that did not differ detectably from that of normal tobacco mitochondrial DNA. Southern blots of tumor chloroplast and mitochondrial cleavage products did not hybridize with labeled pTi T37 DNA, whereas blots of tumor cell nuclear DNA cleavage products hybridized strongly. We conclude that T-DNA is located not in chloroplasts or mitochondria but rather in the nuclear fraction of this tumor line.

Journal Article↗
PubMedDate not supplied

Molecular changes in Entamoeba histolytica in response to bacteria.

Entamoeba histolytica, the protozoan parasite, is the causative agent of amoebiasis. The degree of virulence, as inferred from invasiveness, of potentially pathogenic strains may be regulated by both host and parasite factors that determine the gut environment. One such factor that plays an important role is the bacterial flora in the gut. Previous studies have clearly shown that bacterial flora is an important determinant of virulence in E. histolytica. However, the exact nature of changes induced in E. histolytica in response to bacteria and their role in virulence is not clear. In this study the levels of a number of molecules potentially important in virulence mechanisms were determined in E. histolytica cells grown with and without normal human bacterial flora, using enzyme-linked immunosorbent assay. Significant changes were observed only after the E. histolytica cells had been adapted to grow with bacterial flora for a number of generations, and not in short term culture.

Animals↗