Search results for " lipase"
showing 10 items of 96 documents
Low-protein diet prevents tissue lipoprotein lipase activity increase in growing rats
2000
The time course of changes in tissue lipolytic activities was studied in young rats during theconsumption of a low-protein diet containing 50 g protein/kg (40 g wheat gluten +10 g casein/kg) for 28 d followed by balanced refeeding with 200 g protein/kg (160 g wheat gluten +40 gcasein/kg) for 28 d. Lipoprotein lipase (LPL) activities were compared with the values of acontrol group fed a balanced diet containing 200 g protein/kg for 56 d. At the end of proteinmalnutrition period, the epididymal fat tissue LPL activity represented 36 %, and that of heartand gastrocnemius was 44 %, of those of the control group. These differences wereaccompanied by lower serum- and VLDL-triacylglycerols (TAG), …
Paracrine Activation of Hepatic CB1 Receptors by Stellate Cell-Derived Endocannabinoids Mediates Alcoholic Fatty Liver
2008
SummaryAlcohol-induced fatty liver, a major cause of morbidity, has been attributed to enhanced hepatic lipogenesis and decreased fat clearance of unknown mechanism. Here we report that the steatosis induced in mice by a low-fat, liquid ethanol diet is attenuated by concurrent blockade of cannabinoid CB1 receptors. Global or hepatocyte-specific CB1 knockout mice are resistant to ethanol-induced steatosis and increases in lipogenic gene expression and have increased carnitine palmitoyltransferase 1 activity, which, unlike in controls, is not reduced by ethanol treatment. Ethanol feeding increases the hepatic expression of CB1 receptors and upregulates the endocannabinoid 2-arachidonoylglycer…
Alterations in the Hippocampal Endocannabinoid System in Diet-Induced Obese Mice
2010
The endocannabinoid (eCB) system plays central roles in the regulation of food intake and energy expenditure. Its alteration in activity contributes to the development and maintenance of obesity. Stimulation of the cannabinoid receptor type 1 (CB1receptor) increases feeding, enhances reward aspects of eating, and promotes lipogenesis, whereas its blockade decreases appetite, sustains weight loss, increases insulin sensitivity, and alleviates dysregulation of lipid metabolism. The hypothesis has been put forward that the eCB system is overactive in obesity. Hippocampal circuits are not directly involved in the neuronal control of food intake and appetite, but they play important roles in hed…
Regulation of lipid flux between liver and adipose tissue during transient hepatic steatosis in carnitine-depleted rats
2007
Rats with carnitine deficiency due to trimethylhydrazinium propionate (mildronate) administered at 80 mg/100 g body weight per day for 10 days developed liver steatosis only upon fasting. This study aimed to determine whether the transient steatosis resulted from triglyceride accumulation due to the amount of fatty acids preserved through impaired fatty acid oxidation and/or from up-regulation of lipid exchange between liver and adipose tissue. In liver, mildronate decreased the carnitine content by approximately 13-fold and, in fasted rats, lowered the palmitate oxidation rate by 50% in the perfused organ, increased 9-fold the triglyceride content, and doubled the hepatic very low density …
Lipoprotein lipase-facilitated uptake of LDL is mediated by the LDL receptor
2007
LPL mediates the uptake of lipoproteins into different cell types independent of its catalytic activity. The mechanism of this process and its physiological relevance are not clear. Taking into account the importance of the endothelial barrier for lipoprotein uptake, in vitro studies with primary aortic endothelial cells from wild-type and low density lipoprotein receptor (LDLR)-deficient (LDLR(-/-)) mice were performed. Addition of LPL almost doubled the uptake of LDL into wild-type cells. However, there was virtually no LPL-mediated change of LDL uptake into LDLR(-/-) cells. Upregulation of LDLR by lipoprotein-deficient serum/lovastatin in wild-type cells resulted in a 7-fold increase of …
Visceral leishmaniasis, hypertriglyceridemia and secondary hemophagocytic lymphohistiocytosis
2016
cytokines, an upregulation of adhesion molecules and MHC I and II molecules on mono/macrophages, and an expansion of inflammatory monocytes. This exaggerated inflammatory response is responsible for necrosis and organ failure and results in uncontrolled proliferation and phagocytic activity of histiocytes [2]. Hypertriglyceridemia (fasting, greater than or equal to 265 mg/100 ml) is one of the current diagnostic criteria for HLH [2]. Several studies link hypertriglyceridemia to inhibition of lipoprotein lipase (LPL) by tumor necrosis factor-α (TNF-α), and TNF-α is a powerful autocrine and paracrine regulator of adipose tissue [3]. Indeed, many different sources of intense and prolonged T-ly…
Issues Affecting Quality of Life and Disease Burden in Lipoprotein Lipase Deficiency (Lpld) - First Step Towards a Pro Measure in Lpld
2015
Objectives: LPLD is an ultra-orphan genetic lipid disorder (prevalence 1-2/million). It is associated with severe hypertriglyceridemia and an increased risk of acute pancreatitis. Other manifestations include eruptive xanthoma, fatigue, difficulty with concentrating and cardiopulmonary symptoms. Associated symptoms, complications and the fat-restricted diet affect Quality of Life (QOL). Currently no disease-specific measure exists to assess QOL and the burden of LPLD. As part of post approval commitments of alipogene tiparvovec, regulatory bodies requested the development of a reliable measure of QOL in LPLD. This study evaluates existing EORTC questionnaires QLQ-C30 and QLQ-PAN26, and a ne…
Enzymatic Synthesis and Antimicrobial Activity of Oligomer Analogues of Medicinal Biopolymers from Comfrey and Other Species of the Boraginaceae Fami…
2022
This study reports the first enzymatic synthesis leading to several oligomer analogues of poly[3-(3,4-dihydroxyphenyl)glyceric acid]. This biopolymer, extracted from plants of the Boraginaceae family has shown a wide spectrum of pharmacological properties, including antimicrobial activity. Enzymatic ring opening polymerization of 2-methoxycarbonyl-3-(3,4-dibenzyloxyphenyl)oxirane (MDBPO) using lipase from Candida rugosa leads to formation of poly[2-methoxycarbonyl-3-(3,4-dibenzyloxyphenyl)oxirane] (PMDBPO), with a degree of polymerization up to 5. Catalytic debenzylation of PMDBPO using H2 on Pd/C yields poly[2-methoxycarbonyl-3-(3,4-dihydroxyphenyl)oxirane] (PMDHPO) without loss in molecul…
Digestive Enzymes in Larvae and Juveniles of Farmed Sharpsnout Seabream (Diplodus puntazzo) (Cetti, 1777)
2011
The ontogenetic development and pattern of main digestive enzyme activities (proteases, carbohydrases and lipases) were investigated in farmed sharpsnout seabream Diplodus puntazzo larvae and juveniles, during the passage from the larval stage to adult (from 21 to 277 days after hatching - DAH). Larvae showed exponential growth, thus confirming that Rotifers and Artemia nauplii are suitable preys for early feeding of D. puntazzo larvae. Pepsin activity was low in the larvae, but it increased afterwards in relation with stomach development. In juveniles, levels of specific activity of trypsin, chymotrypsin and elastase were lower compared to that recorded in larvae. A decrease in the activit…
Estrogen increases hepatic lipase levels in inbred strains of mice: A possible mechanism for estrogen-dependent lowering of high density lipoprotein
2001
We have shown mouse to be an useful animal model for studies on the estrogen-mediated synthesis and secretion of lipoproteins since, unlike in rats, low density lipoprotein receptors are not upregulated in mice [3]. This results into the elevation of plasma levels of apolipoprotein (apo) B and apoE, and lowering of apoA-I-containing particles. The mechanisms of apoB and apoE elevation by estrogen have been elucidated [6], but the mechanism of lowering of plasma levels of HDL is still not known. Among other factors, apoA-I, cholesterol ester transfer protein (CEPT), scavenger receptor B1 (SR-B1), and hepatic lipase are potential candidates that modulate plasma levels of HDL. Since estrogen t…