Mahmood M Hussain

..This review highlights recent studies examining light- and food-entrained regulation of plasma lipids and of various intestinal activities and offers insight into the role of the intestine in food entrainment...

..It is largely due to their support and expertise that we have been able to publish high-standard manuscripts. We would also like to thank authors for choosing Nutrition & Metabolism and contributing their cherished work...

..To summarize the new knowledge about the regulation of dietary lipid absorption by circadian locomotor output cycles kaput (Clock) and Nocturnin...

..However, specific steps in lipoprotein assembly that require apoB-MTP binding have not been identified. ApoB-MTP binding may be important for the prevention of degradation and lipidation of nascent apoB...

..It is also speculated that MTP may function in physiologic processes beyond lipoprotein assembly...

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..In this review we propose a nomenclature for these lipoproteins and have summarized recent data about their intracellular assembly and factors that modulate their secretion...

..Identification of MTP inhibitors, which selectively affect transfer of a specific lipid class, may have therapeutic potential...

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..Furthermore, environmental factors, such as food and light, play an important role in MTP regulation...

..This review summarizes recent advances about the role of microsomal triglyceride transfer protein in plasma and tissue lipid homeostasis...

..Clock plays an important role in light and food entrainment of intestinal functions by regulating nutrient transport proteins. Disruptions in intestinal circadian activity may contribute to hyperlipidemia and hyperglycemia...

..Conversely, knockdown of IRE1beta enhanced MTP expression. These studies show that IRE1beta plays a role in regulating MTP and in chylomicron production...

..Instead, we found that enterocytes express LEPR, POMC, AGRP, and MC4R. We propose that a peripheral, local gut signaling mechanism involving LEPR B and MC4R regulates intestinal MTP and controls intestinal lipid absorption...

..Transport via I-HDL might contribute to vitamin E absorption in patients with abetalipoproteinemia receiving large oral doses of the vitamin...

..Our aim was to elucidate mechanisms involved in the acquisition of lipid transport properties during enterocyte differentiation...

..We speculate that non-lipoprotein-producing cells may use different mechanisms to alleviate product inhibition and modulate cholesteryl ester biosynthesis...

..Together, these studies describe a role of Clock/Shp in the diurnal regulation of MTP and plasma triglyceride and indicate that disruptions in circadian regulation might cause hyperlipidemia...

..This may be also true for ABCA1 which locates on basal membrane of enterocytes. Manipulation of SPT activity could thus provide a novel alternative treatment for dyslipidemia...

..In this regulation, the presence of cytokine-responsive motif in the tissue-specific enhancer element confers cell-specific response...

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..Absorption with chylomicrons is the major pathway of vitamin E absorption. The HDL pathway may be important when chylomicron assembly is defective and can be exploited to deliver vitamin E without increasing fat consumption...

..These studies identify MTP as a major target of CCl(4) and its degradation as a novel mechanism involved in the onset of steatosis, suggesting that inhibition of proteolysis may prevent some forms of steatosis...

..We therefore investigated liver MTP gene expression and its lipid transfer activity in untreated cases infected with the major HCV genotypes showing variable degrees of hepatic steatosis...

..Nonetheless, long-term studies involving multiple feedings showed significant reduction in cholesterol absorption after 4 days. We propose that multiple compensatory mechanisms ensure efficient cholesterol absorption in mice...

..This new observation that extracellular matrix proteins can enhance apoB secretion in Caco-2 cells could be useful to explore the modulation of lipid transport by these proteins...

..Because small intestine is one of the major tissue expressing PLTP, we hypothesize that PLTP deficient small intestine absorbs less cholesterol, thus contributing to the diminishing of cholesterol levels in the plasma...

..These methods may help identify specific inhibitors for individual lipid transfer activities, in characterizing different domains involved in transfer, and in the isolation of mutants that bind but cannot transfer lipids...

..They inhibit fat absorption by decreasing TG transport to the endoplasmic reticulum and increase drug efficacy against cancer cells by competing for their excretion...

..The findings reported here provide new information on specific domains of F11R that can lead to the generation of therapeutic agents expected to be useful in the treatment of cardiovascular diseases...

..Furthermore, the assay was useful in studying the inhibition of the cellular as well as purified MTP by its antagonists. This new method is amenable to automation and can be easily adopted for large-scale, high-throughput screening...

..Agents that block the F11R-mediated adhesion of platelets to EC may be of therapeutic value in controlling thrombosis and preventing heart attacks and stroke...

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