Phospholipid metabolism and protein kinase C mediated protein phosphorylation in dietary protein deficiency in rat lung

606-613Nutritional deprivation of proteins decreases the protein kinase C (PKC) activity in rat lung. The activity of (PKC) is influenced by lipid metabolism. Changes in PKC activity may influence phosphorylation of its substrate proteins in the tissues. Therefore, alterations in phospholipid metabolism and PKC mediated protein phosphorylation in dietary protein deficiency in rat lung were envisaged. The study was conducted on rats fed on three different types of diet viz .. casein (20% protein), deficient (4% protein, rice flour as source of protein) and supplemented (deficient diet supplemented with L-Iysine and DL-threoning). Feeding of protein deficient diet caused reduction in incorporation of [3H] myo-inositol in the total phosphoinositides in lungs and an increase in total inositol phosphate pool. There was a significant reduction in the contents and turnover rate of phosphatidyl inositol and phosphatidyl inositol monophosphate. Supplementation of diet with L-Iysine and DL-threonine had a reversing effect on total pool of phosphoinositides and, the metabolism of phosphatidyl inositol bisphosphate and phosphatidyl inositol. In phosphatidyl choline metabolism, the dietary protein deficiency led to a decrease in incorporation of [14C-methyl] choline-chloride in total phospholipids. In contrast, its incorporation increased in phosphatidyl choline pool. The contents of phosphatidyl choline and residue, incorporation of [14C-methyl] choline-chloride in them and their turnover rate also increased. Supplementation of diet had a reversal effect on most of these parameters. Phosphorylation of proteins of 84,47,35 and 16 kDa was identified to be mediated by PKC. In dietary protein deficiency, phosphorylation of all these proteins, except that of 47 kDa, increased. Supplementation of diet reversed the pattern except that of 84 kDa. The findings suggest that changes in phospholipid metabolism in dietary protein deficiency may effect the activity of PKC thereby influencing the phosphorylation of its substrate proteins and hence associated functions that may lead to pathophysiology of lung

Effect of feeding protein deficient diet on phospholipid turnover and protein kinase C mediated protein phosphorylation in rat brain

323-331Feeding of protein deficient diet is known to alter the transmembrane signalling in brain of rat by reducing total protein kinase C (PKC) activity. Phospholipid metabolism regulates the activation of PKC through generation of second messengers and the extent of PKC activation accordingly influences the magnitude of phosphorylation of its endogenous substrate proteins.Thus it was speculated that ingestion of protein deficient diet may modify the turnover rate of membrane phospholipids and magnitude of phosphorylation of endogenous substrate proteins of PKC. The experiments were conducted on rats fed on three different types of laboratory prepared diets viz. casein (20% casein), deficient (4% protein, rice flour as source of protein ) and supplemented (deficient diet supplemented with L-lysine and DL-threonine) for 28 days. The metabolism of phosphoinositides (PIs) and phosphatidyl choline (PC) was studied by equilibrium labeling with [3H] myo inositol and [14C methyl] choline chloride respectively. The phosphorylation of endogenous substrate proteins of PKC was studied by using 32P-γ-ATP followed by SDS-PAGE and autoradiography. The results suggest that in deficient group, there is an increased incorporation of [3H] myo inositol in PIs and inositol phosphate pool in comparison to the casein group. The phosphatidyl inositol (PI) turnover reduced, although there was a marginal increase in the phosphatidyl inositol monophosphate (PIP) and phosphatidyl inositol bis phosphate (PIP2). Supplementation of diet showed a reversal of the pattern towards control to a considerable extent. In the deficient group, PC metabolism showed an increased incorporation of [14C methyl] choline in choline phospholipids but decreased incorporation in phosphoryl choline in comaprison with the casein group. The increase in total PC contents was significant but marginal in residue contents. The turnover rate of PC increased only marginally and that of residue declined. Supplementation of diet reduced the total contents of PC and residue, but the turnover rate of PC and residue remained still higher. Phosphorylation of endogenous proteins showed four different proteins of 78, 46, 33 and 16 kDa to be the substrates of PKC in casein group. In deficient group, phosphorylation of these proteins increased markedly while supplementation of diet had a reversing effect rendering the values to be intermediate between casein and the supplemented group. The changes in phospholipid metabolism and in phosphorylation of endogenous substrate proteins of PKC suggest that dietary protein deficiency causes alterations in transmembrane signalling mechanism in rat brain. These effects are partially reversed by improving the quality of proteins in the diet

Effect of feeding protein deficient diet on phospholipid turnover and protein kinase C mediated protein phosphorylation in rat brain

Feeding of protein deficient diet is known to alter the transmembrane signalling in brain of rat by reducing total protein kinase C (PKC) activity. Phospholipid metabolism regulates the activation of PKC through generation of second messengers and the extent of PKC activation accordingly influences the magnitude of phosphorylation of its endogenous substrate proteins. Thus it was speculated that ingestion of protein deficient diet may modify the turnover rate of membrane phospholipids and magnitude of phosphorylation of endogenous substrate proteins of PKC. The experiments were conducted on rats fed on three different types of laboratory prepared diets viz. casein (20% casein), deficient (4% protein, rice flour as source of protein) and supplemented (deficient diet supplemented with L-lysine and DL-threonine) for 28 days. The metabolism of phosphoinositides (PIs) and phosphatidyl choline (PC) was studied by equilibrium labeling with [3H] myo inositol and [14C methyl] choline chloride respectively. The phosphorylation of endogenous substrate proteins of PKC was studied by using 32P-γ-ATP followed by SDS-PAGE and autoradiography. The results suggest that in deficient group, there is an increased incorporation of [3H] myo inositol in PIs and inositol phosphate pool in comparison to the casein group. The phosphatidyl inositol (PI) turnover reduced, although there was a marginal increase in the phosphatidyl inositol monophosphate (PIP) and phosphatidyl inositol bis phosphate (PIP2). Supplementation of diet showed a reversal of the pattern towards control to a considerable extent. In the deficient group, PC metabolism showed an increased incorporation of [14C methyl] choline in choline phospholipids but decreased incorporation in phosphoryl choline in comparison with the casein group. The increase in total PC contents was significant but marginal in residue contents. The turnover rate of PC increased only marginally and that of residue declined. Supplementation of diet reduced the total contents of PC and residue, but the turnover rate of PC and residue remained still higher. Phosphorylation of endogenous proteins showed four different proteins of 78, 46, 33 and 16 kDa to be the substrates of PKC in casein group. In deficient group, phosphorylation of these proteins increased markedly while supplementation of diet had a reversing effect rendering the values to be intermediate between casein and the supplemented group. The changes in phospholipid metabolism and in phosphorylation of endogenous substrate proteins of PKC suggest that dietary protein deficiency causes alterations in transmembrane signalling mechanism in rat brain. These effects are partially reversed by improving the quality of proteins in the diet

An Improved 2-Dimensional Gel Electrophoresis Method for Resolving Human Erythrocyte Membrane Proteins

The 2-dimensional gel electrophoresis (2-DE) technique is widely used for the analysis of complex protein mixtures extracted from biological samples. It is one of the most commonly used analytical techniques in proteomics to study qualitative and quantitative protein changes between different states of a cell or an organism (eg, healthy and diseased), conditionally expressed proteins, posttranslational modifications, and so on. The 2-DE technique is used for its unparalleled ability to separate thousands of proteins simultaneously. The resolution of the proteins by 2-DE largely depends on the quality of sample prepared during protein extraction which increases results in terms of reproducibility and minimizes protein modifications that may result in artifactual spots on 2-DE gels. The buffer used for the extraction and solubilization of proteins influences the quality and reproducibility of the resolution of proteins on 2-DE gel. The purification by cleanup kit is another powerful process to prevent horizontal streaking which occurs during isoelectric focusing due to the presence of contaminants such as salts, lipids, nucleic acids, and detergents. Erythrocyte membrane proteins serve as prototypes for multifunctional proteins in various erythroid and nonerythroid cells. In this study, we therefore optimized the selected major conditions of 2-DE for resolving various proteins of human erythrocyte membrane. The modification included the optimization of conditions for sample preparation, cleanup of protein sample, isoelectric focusing, equilibration, and storage of immobilized pH gradient strips, which were further carefully examined to achieve optimum conditions for improving the quality of protein spots on 2-DE gels. The present improved 2-DE analysis method enabled better detection of protein spots with higher quality and reproducibility. Therefore, the conditions established in this study may be used for the 2-DE analysis of erythrocyte membrane proteins for different diseases, which may help to identify the proteins that may serve as markers for diagnostics as well as targets for development of new therapeutic potential

The biology of cataract. The Hyderabad cataract research group

This article does not have an abstract

Early and mid-term results of minimally invasive coronary artery bypass grafting

Introduction: Minimally invasive coronary artery bypass grafting (MICABG) is a less invasive method of performing surgical revascularization. This technique coupled with use of off pump technique of surgical revascularization makes it truly less invasive. This method is highly effective even in high-risk patients. Results of this procedure are comparable to standard off pump technique and are better than percutaneous coronary intervention utilizing drug-eluting stent. We present an early and mid-term result of the use of this technique. Method: We enrolled 33 patients for analysis operated between 2008 and 2012. Operation was performed utilizing off-pump technique of coronary artery bypass grafting through a minimal invasive incision. Left internal mammary artery graft was done for single vessel disease and radial artery was utilized for other grafts if required. Median follow up of 2.5 years (6 months–4 years) is available. Results: Median age was 58.5 years (41–77) and all were male. Single vessel disease was present in 7, double vessel in 14 and triple vessel disease in 12 patients. All the patients had normal left ventricular size and function. There was no operative and 30-day mortality. Conversion to median sternotomy to complete the operation was done in 6.6% (2 out of 33 patients). One patient had acute myocardial infarction and there were no deaths during follow up. Conclusion: MICABG is a safe and effective method of revascularization in low risk candidates for coronary artery bypass grafting

Isolation of a new flavonoid and waste to wealth recovery of 6-<i>O</i>-Ascorbyl Esters from Seeds of <i>Aegle marmelos</i> (family- Rutaceae)

<p><i>Aegle marmelos</i> is a plant species native to India. Commercially available food products such as jam, jelly, candy, squash etc. are prepared from ripe fruit pulp of <i>A. marmelos</i>. Ripe fruit processing accounts for 60% of whole fruit mass while 40% remains unutilized and generates waste (hard shell, pomace, fiber and seeds) on a massive scale which do not have high value applications. A new flavone 3,5,7-trihydroxy-2-(4′-hydroxy-3′-isopentyloxyphenyl-4<i>H</i>-chromen-4-one (<b>5</b>) in addition to the known compounds <b>1–4</b>, has been isolated from seeds of <i>A. marmelos</i>. Also, compound 7-(3′-methylbut-2′-enyloxy)-2<i>H</i>-chromen-2-one (<b>2)</b> has been isolated for the first time from <i>A. marmelos</i>. The structure of compounds <b>1–5</b> was determined by spectral analysis (UV, IR, NMR, etc.). Additionally, the non-edible oil obtained from seeds was investigated for waste to wealth recovery of 6-<i>O</i>-ascorbyl esters in high regioselectivity <i>via</i> one step semi-synthetic approach in the presence of ascorbic acid and H₂SO₄ at ambient temperature.</p