Lipogenesis

About: Lipogenesis is a research topic. Over the lifetime, 7689 publications have been published within this topic receiving 324036 citations.

Sources of fatty acids stored in liver and secreted via lipoproteins in patients with nonalcoholic fatty liver disease.

Abstract: Nonalcoholic fatty liver disease (NAFLD) is characterized by the accumulation of excess liver triacylglycerol (TAG), inflammation, and liver damage The goal of the present study was to directly quantify the biological sources of hepatic and plasma lipoprotein TAG in NAFLD Patients (5 male and 4 female; 44 ± 10 years of age) scheduled for a medically indicated liver biopsy were infused with and orally fed stable isotopes for 4 days to label and track serum nonesterified fatty acids (NEFAs), dietary fatty acids, and those derived from the de novo lipogenesis (DNL) pathway, present in liver tissue and lipoprotein TAG Hepatic and lipoprotein TAG fatty acids were analyzed by gas chromatography/mass spectrometry NAFLD patients were obese, with fasting hypertriglyceridemia and hyperinsulinemia Of the TAG accounted for in liver, 590% ± 99% of TAG arose from NEFAs; 261% ± 67%, from DNL; and 149% ± 70%, from the diet The pattern of labeling in VLDL was similar to that in liver, and throughout the 4 days of labeling, the liver demonstrated reciprocal use of adipose and dietary fatty acids DNL was elevated in the fasting state and demonstrated no diurnal variation These quantitative metabolic data document that both elevated peripheral fatty acids and DNL contribute to the accumulation of hepatic and lipoprotein fat in NAFLD

Subcutaneous and visceral adipose tissue : Their relation to the metabolic syndrome

Abstract: Methods for assessment, e.g., anthropometric indicators and imaging techniques, of several phenotypes of human obesity, with special reference to abdominal fat content, have been evaluated. The correlation of fat distribution with age, gender, total body fat, energy balance, adipose tissue lipoprotein lipase and lipolytic activity, adipose tissue receptors, and genetic characteristics are discussed. Several secreted or expressed factors in the adipocyte are evaluated in the context of fat tissue localization. The body fat distribution and the metabolic profile in nonobese and obese individuals is discussed relative to lipolysis, antilypolysis and lipogenesis, insulin sensitivity, and glucose, lipid, and protein metabolism. Finally, the endocrine regulation of abdominal visceral fat in comparison with the adipose tissue localized in other areas is presented.

Fatty acid synthase and the lipogenic phenotype in cancer pathogenesis

Abstract: Fatty acid synthase (FASN) catalyses the synthesis of fatty acids, and this synthetic pathway is upregulated in many tumours. How might FASN and increased lipogenesis be involved in cancer, and is FASN a valid therapeutic target? There is a renewed interest in the ultimate role of fatty acid synthase (FASN) — a key lipogenic enzyme catalysing the terminal steps in the de novo biogenesis of fatty acids — in cancer pathogenesis. Tumour-associated FASN, by conferring growth and survival advantages rather than functioning as an anabolic energy-storage pathway, appears to necessarily accompany the natural history of most human cancers. A recent identification of cross-talk between FASN and well-established cancer-controlling networks begins to delineate the oncogenic nature of FASN-driven lipogenesis. FASN, a nearly-universal druggable target in many human carcinomas and their precursor lesions, offers new therapeutic opportunities for metabolically treating and preventing cancer.

Mechanisms for insulin resistance: common threads and missing links.

Abstract: Insulin resistance is a complex metabolic disorder that defies explanation by a single etiological pathway. Accumulation of ectopic lipid metabolites, activation of the unfolded protein response (UPR) pathway, and innate immune pathways have all been implicated in the pathogenesis of insulin resistance. However, these pathways are also closely linked to changes in fatty acid uptake, lipogenesis, and energy expenditure that can impact ectopic lipid deposition. Ultimately, these cellular changes may converge to promote the accumulation of specific lipid metabolites (diacylglycerols and/or ceramides) in liver and skeletal muscle, a common final pathway leading to impaired insulin signaling and insulin resistance.

Role of LXRs in control of lipogenesis

Abstract: The discovery of oxysterols as the endogenous liver X receptor (LXR) ligands and subsequent gene targeting studies in mice provided strong evidence that LXR plays a central role in cholesterol metabolism. The identification here of a synthetic, nonsteroidal LXR-selective agonist series represented by T0314407 and T0901317 revealed a novel physiological role of LXR. Oral administration of T0901317 to mice and hamsters showed that LXR activated the coordinate expression of major fatty acid biosynthetic genes (lipogenesis) and increased plasma triglyceride and phospholipid levels in both species. Complementary studies in cell culture and animals suggested that the increase in plasma lipids occurs via LXR-mediated induction of the sterol regulatory element-binding protein 1 (SREBP-1) lipogenic program.