Induction by leptin of uncoupling protein-2 and enzymes of fatty acid oxidation

We have studied mechanisms by which leptin overexpression, which reduces body weight via anorexic and thermogenic actions, induces triglyceride depletion in adipocytes and nonadipocytes. Here we show that leptin alters in pancreatic islets the mRNA of the genes encoding enzymes of free fatty acid metabolism and uncoupling protein-2 (UCP-2). In animals infused with a recombinant adenovirus containing the leptin cDNA, the levels of mRNAs encoding enzymes of mitochondrial and peroxisomal oxidation rose 2- to 3-fold, whereas mRNA encoding an enzyme of esterification declined in islets from hyperleptinemic rats. Islet UCP-2 mRNA rose 6-fold. All in vivo changes occurred in vitro in normal islets cultured with recombinant leptin, indicating direct extraneural effects. Leptin overexpression increased UCP-2 mRNA by more than 10-fold in epididymal, retroperitoneal, and subcutaneous fat tissue of normal, but not of leptin-receptor-defective obese rats. By directly regulating the expression of enzymes of free fatty acid metabolism and of UCP-2, leptin controls intracellular triglyceride content of certain nonadipocytes, as well as adipocytes.     

The FML (Fucose Mannose Ligand) of Leishmania donovani. a new tool in diagnosis, prognosis, transfusional control and vaccination against human kala-azar

Upon fractionation of a post mitochondrial supernatant from rat liver, phosphorylase kinase activity was largely recovered in the cytosol and the smooth endoplasmic reticulum (SER) fraction. The presence of phosphorylase kinase in SER vesicles was not due to an interaction of the enzyme with glycogen particles, since previous elimination of SER glycogen either by 48 h animal starvation or by treatment of the membrane fraction with alpha-amylase did not significantly alter phosphorylase kinase activity content. Washing of the initial pellet of SER fraction (crude SER) by dilution and recentrifugation, released in the supernatant an amount of phosphorylase kinase activity, which is dependent on: i) the degree of dilution, ii) the number of washes, iii) the ionic strength of the washing solution and iii) the presence or absence of Ca2+. Crude SER-associated phosphorylase kinase was marginally affected by increased concentrations of antibody against rabbit skeletal muscle holoenzyme which nevertheless drastically inhibited cytosolic enzyme activity, while it showed a higher resistance to partial proteolysis and a different Western blotting profile with anti-phosphorylase kinase when compared with the soluble kinase. A small but significant fraction of SER phosphorylase kinase was strongly associated with the microsomal fraction being partly extractable only in presence of detergents. This membrane-bound enzyme form exhibited an alkaline pH optimum, in contrast to the neutral pH optima of both soluble and weakly associated phosphorylase kinase.     

Use of intraaortic balloon counterpulsation in patients presenting with cardiogenic shock: observations from the GUSTO-I Study. Global Utilization of Streptokinase and TPA for Occluded Coronary Arteries

OBJECTIVES: We sought to examine the use, complications and outcomes with early intraaortic balloon counterpulsation (IABP) in patients presenting with cardiogenic shock complicating acute myocardial infarction and treated with thrombolytic therapy. BACKGROUND: The use of IABP in patients with cardiogenic shock is widely accepted; however, there is a paucity of information on the use of this technique in patients with cardiogenic shock who are treated with thrombolytic therapy. METHODS: Patients who presented within 6 h of chest pain onset were randomized to one of four thrombolytic regimens. Cardiogenic shock was not an exclusion criterion, and data for these patients were prospectively collected. Patients presenting with shock were classified into early IABP (insertion within one calendar day of enrollment) or no IABP (insertion on or after day 2 or never). RESULTS: There were 68 (22%) IABP placements in 310 patients presenting with shock. Early IABP use occurred in 62 patients (20%) and none in 248 (80%). Most IABP use occurred in the United States (59 of 68 IABP placements) involving 32% of U.S. patients presenting with shock. Despite more adverse events in the early IABP group and more episodes of moderate bleeding, this cohort showed a trend toward lower 30-day and 1-year mortality rates. CONCLUSIONS: IABP appears to be underutilized in patients presenting with cardiogenic shock, both within and outside the United States. Early IABP institution is associated with an increased risk of bleeding and adverse events but a trend toward lower 30-day and 1-year all-cause mortality.     

Effect of seminal plasma on implantation rates

Of 2774 consecutive, prospectively documented fractures of the distal radius, 225 (8 per cent) occurred as sports injuries, mainly in young men. Soccer produced the greatest number of wrist fractures with 112 cases (50 per cent). Skiing, dancing and rugby caused 12 per cent, 9 per cent and 7 per cent of all sporting wrist fractures respectively. Skiing, horseriding and dancing consistently resulted in more complex fractures. In soccer, synthetic pitches increased the likelihood of a fracture following a fall by a factor of five. Twelve per cent of fractures required further treatment because of instability leading to redisplacement. The complication rate was 14 per cent with the majority being cases of malunion (12 per cent). Of the 131 patients who returned a questionnaire, 72.5 per cent had returned to their original sport. This was influenced mainly by the patient's age and pre-injury standard of competition.     

Changes in hepatic nitrogen balance in plasma concentrations of amino acids and hormones and in cell volume after overnight fasting in perinatal and adult rat

Important regulatory factors of intrahepatic protein synthesis and proteolysis are amino acids, glucagon, insulin, and cell volume. We have investigated the changes in these factors with development and after an overnight fast and evaluated their contribution to changes in the hepatic nitrogen balance in vivo. In the fed state, glucagon levels were highest in suckling animals and gradually declined in older rats, whereas the concentration of insulin increased during development. The amino acid concentrations in liver and plasma declined during the suckling period to levels that in vitro are highly permissive for induction of autophagic proteolysis. In all age groups investigated, fasting was associated with a drop in hepatic protein content, together with a marked decrease in hepatocellular volume and insulin concentrations. On the other hand, glucagon concentrations and the concentration of many amino acids in plasma and liver responded to fasting with a pronounced decrease in perinatal and suckling animals, but this response had become blunted at weaning and had disappeared in adult animals. These findings suggest that insulin and/or hepatocellular volume are more likely candidates as short-term physiologic regulators of the hepatic nitrogen balance than are glucagon or amino acids. In glucose-supplemented fetuses, high levels of insulin could not compensate for a decreased hepatocellular volume in averting a catabolic state, suggesting that cell volume is the more important factor. Although our study cannot discriminate between the effects of fasting on protein synthesis and degradation, our findings show unequivocally that, for a rapid growth of the liver, suckling animals have to be fed around-the-clock.     

Ligand-induced translocation of epidermal growth factor receptor to the nucleus of NR6/HER fibroblasts is serum dependent

Ligand-induced translocation of epidermal growth factor receptors (EGF-R) to the nucleus of NR6/HER fibroblasts has been studied by immunoelectron microscopy. Following treatment of NR6/HER cells with epidermal growth factor (EGF) for 1 h, there was a decrease in EGF-R labeling at the plasma membrane and a corresponding increase in EGF-R in the nucleus. This was preceded by a rapid and sustained increase in nuclear phosphotyrosine content, detectable within 2 min of EGF treatment. EGF-R translocation into the nucleus was completely prevented by 18 h serum starvation prior to treatment with EGF. These results indicate that translocation of EGF-R to the nucleus is a controlled process and they suggest that EGF-R may directly influence nuclear function.     

Oxidative stress-inducible protein tyrosine phosphatase in glomerulonephritis

Previously we found that rat mesangial cells express 3CH134/CL100 protein-tyrosine phosphatase (PTPase) in response to reactive oxygen intermediates (ROIs), and we now extend these studies to glomerulonephritis (GN), where ROI have been demonstrated to play a role. The rat homologue of 3CH134/CL100 was cloned from a rat macrophage cDNA library. The rat 3CH134/CL100 mRNA was strongly induced in the lung, liver, and heart the first day after birth, suggesting that hyperoxic adaption might be involved in the induction of the PTPase mRNA. In anti-glomerular basement membrane (GBM) antibody (Ab) GN in rats, the 3CH134/CL100 PTPase mRNA was expressed in glomeruli as early as 30 minutes after anti-GBM Ab injection. The 3CH134/CL100 mRNA expression was modulated by the ROI scavenger dimethylthiourea (DMTU), indicating that its induction was ROI related. In contrast to the glomerular lesion, PTPase mRNA expression was not induced in experimental tubulointerstitial nephritis. In situ hybridization suggested that mesangial and some infiltrating cells were the major glomerular cell sources of the PTPase mRNA. These results indicate that rat CCH134/CL100 PTPase is actively induced in glomeruli as part of an acute immune injury at least in part related to oxidative stress. PTPase induction in GN and potentially other forms of inflammation may play an important regulatory role in protein kinase signaling pathways.