China
Africa
Explore chapters and articles related to this topic
Gene–Diet Interactions
Published in Nathalie Bergeron, Patty W. Siri-Tarino, George A. Bray, Ronald M. Krauss, Nutrition and Cardiometabolic Health, 2017
Silvia Berciano, Jose M. Ordovas, Nathalie Bergeron, Patty W. Siri-Tarino, George A. Bray, Ronald M. Krauss
Perilipin proteins were identified in the adipocyte, where they regulate lipid storage and lipolysis. Perilipin 1 (PLIN1) is the most abundant of the adipocyte proteins, and over a decade ago we began to investigate associations of the PLIN1 locus with obesity and related phenotypes focusing on six SNPs (rs2289487, rs1561726, rs2304794, rs894160, rs2304795, rs1052700) (Qi et al., 2004a,b, 2015). These studies revealed relatively consistent and gender-specific (women only) associations between the SNPs and anthropometric and metabolic traits in different ethnic groups and geographical locations.
Increasing the Sensitivity of Adipocytes and Skeletal Muscle Cells to Insulin
Published in Christophe Wiart, Medicinal Plants in Asia for Metabolic Syndrome, 2017
Butanol extract of rhizomes Polygonum cuspidatum Siebold & Zucc. inhibited the enzymatic activity of pancreatic lipase with an IC50 value equal to 15.8 μg/mL.49 This extract at 25 μg/mL inhibited 3T3-L1 preadipocyte differentiation into adipocyte concomitantly with a decrease in glycerol-3-phosphate dehydrogenase, decrease in expression adipocyte differentiation-related protein, perilipin, adipogenic transcription factors peroxisome proliferator-activated receptor-γ, and CCAAT/enhancer-binding protein-α whereby phosphorylated adenosine monophosphate-activated protein kinase was boosted.49 In adipocytes, the activation of peroxisome proliferator-activated receptor-γ activates perilipin.50
Cellular and Molecular Mechanisms of Plaque Rupture
Published in Levon Michael Khachigian, High-Risk Atherosclerotic Plaques, 2004
Transcriptional profiling has recently shown selective expression of a novel gene, perilipin, in ruptured human plaques. This is of considerable interest because perilipin inhibits lipid hydrolysis and may contribute to an accumulation of lipids in the core, thereby contributing to plaque vulnerability.50 In addition, the lipid core contains prothrombotic oxidized lipids and is impregnated with procoagulant tissue factor derived from apoptotic macrophages. Tissue factor makes the lipid core highly thrombogenic when exposed to circulating blood.51–55
Jateorhizine alleviates insulin resistance by promoting adipolysis and glucose uptake in adipocytes
Published in Journal of Receptors and Signal Transduction, 2021
Changqin Cheng, Zhiyong Li, Min Zhang, Dezhi Chen
In order to further verify the pro-adipolysis effect of Jat, the expression levels of adipose transcription factors and related proteins were further determined, including PPARγ, C/EBPα, FABP4, perilipin and FAS. Specifically expressed in adipose tissues, PPARγ is an internal regulatory point for adipocyte differentiation, which can affect adipocyte differentiation process by regulating the expression of key enzymes or transporters in lipid metabolism [19]. C/EBPα, which is expressed late in adipocyte differentiation, activates target genes in adipocytes and collaborates with PPARγ to trigger adipocyte differentiation [20]. FABP4 is an important intracellular fatty acid carrier protein that promotes lipid droplet formation by regulating the uptake, transport and oxidation of fatty acids and their derivatives [21]. Perilipin can form a protective cover on the surface of lipid droplets to prevent lipase contact, thus inhibiting fat decomposition [22]. FAS can catalyze the conversion of acetyl-CoA and malonyl-CoA into fatty acids, leading to the deposition of fat in the body [23]. In short, elevated levels of PPARγ, C/EBPα, FABP4, perilipin and FAS represent increased production of fat, while decreases in these indicators accelerates adipolysis. In this present study, we found that the expression levels of PPARγ, C/EBPα, FABP4, perilipin and FAS were significantly increased in MID-induced preadipocytes, which were reversed by Jat in a concentration-dependent manner. These further indicated that Jat could regulate adipolysis in cells by regulating the expression of fat transcription factors and related proteins.
Thymoquinone and quercetin protect against hepatic steatosis in association with SIRT1/AMPK stimulation and regulation of autophagy, perilipin-2, and cytosolic lipases
Published in Archives of Physiology and Biochemistry, 2023
Hend Ashour, Laila A. Rashed, Radwa T. M. Hassanein, Basma E. Aboulhoda, Hasnaa A. Ebrahim, Mohamed H. Elsayed, Miran A. Elkordy, Omaima M. Abdelwahed
The pathophysiological mechanism of hepatic lipid turnover in NAFLD is complex and is augmented by inflammation and oxidative stress (Chen et al. 2017). The interplay between hepatic cytoplasmic lipid droplets (LDs) accumulation and cytosolic lipolysis is regulated by lipid-forming enzymes, perilipin-2, and lipases. Perilipin-2 is a cytoplasmic LDs scaffolding protein present in the surface of LDs and is associated with LDs preservation (Orlicky et al. 2019). In face of lipolysis, high-fat diet is found to upregulate perilipin-2 (la Fuente et al. 2019) which results in cytoplasmic LDs accumulation. Furthermore, deletion of hepatic perilipin-2 gene in mice fed on a high-fat diet significantly (i) protected against non-alcoholic steatohepatitis (NASH) and liver fibrosis; and (ii) decreased hepatic infiltration of inflammatory cells (Orlicky et al. 2019). These findings point to the importance of perilipin-2 in NAFLD pathophysiology (Orlicky et al. 2019). On the other hand, hepatic lipolysis is enhanced and controlled by cytosolic lipase activity involving adipose triglyceride lipase (ATGL), which is a major hepatic lipase regulating triacylglycerol turnover (Sathyanarayan et al. 2017). In addition, lipophagy is the process of LDs mobilisation through autophagy pathway activation (Singh and Cuervo 2012). A link between hepatic lipophagy and lipid metabolism has been postulated, as the activated lipophagy promoted hepatic lipolysis which was mediated through perilipin-2 degradation (Kaushik and Cuervo 2015). Therefore, the integration between lipophagy and the hepatocyte LD catabolism may promote hepatic fatty acids hydrolysis and degradation.
Antitubercular drugs induced liver injury: an updated insight into molecular mechanisms
Published in Drug Metabolism Reviews, 2023
RIF administration in mice enhances the expression of several key genes involved in fatty acid synthesis, including fatty acid synthase, acetyl-CoA carboxylase, and stearoyl-CoA desaturase-1 without inducing the expression of the sterol regulatory element-binding protein-1c gene and liver X receptor α. The expression of CD36, a signaling receptor, responsible for fatty acid uptake by hepatocytes also increased after RIF administration in mice (Huang et al. 2016). Thus, it is clear that RIF induces gene expression of enzymes involving fatty acid synthesis from acetyl‐CoA (de novo lipogenesis). Peroxisome proliferator-activated receptor gamma (PPARγ) plays a critical role in the differentiation and proliferation of adipose tissues (Sun et al. 2021). PPARγ has been shown to upregulate during the fatty liver condition (Lee et al. 2018). RIF is a pregnane X receptor (PXR) ligand that activates PXR expression in the liver tissue of mice. PPARγ, a downstream target of PXR, was transcriptionally up-regulated (nearly 10 folds) in the liver after four weeks of RIF administration (Huang et al. 2016). RIF was shown to induce the expression of PPAR-γ and its downstream proteins such as apolipoprotein C-III, acyl-CoA-binding protein, 3-ketoacyl-CoA, thiolase A and B and perilipin-2 by activating PXR in the liver to increase fatty infiltration into the liver and enhance lipid content in the blood, resulting in lipid accumulation (Kim et al. 2017). Perilipins are intracellular lipid droplets that coat proteins (Libby et al. 2016) known to suppress triglyceride breakdown into glycerol and free fatty acids (lipolysis) for use in metabolism. Perilipin-2 has been implicated in fatty liver formation in nonalcoholic fatty liver disease. Proteomic studies from Kim et al. (2017) reported an increased expression of perilipin-2 after RIF administration in mice, suggesting increased perilipin-2 can cause lipid accumulation in the liver. Thus, studies have clearly shown that RIF could upregulate lipogenic transcription factors such as PPAR-γ and PXR thereby increasing the fatty acid uptake by the liver via enhanced expression of CD36 (Figure 4).