microRNA lipid

Obesity, which has become a major global epidemic, is associated with numerous comorbidities and nearly every chronic condition. Mitochondria play a central role in this disorder as they control cell metabolism, regulating important processes such as ATP production, lipid β-oxidation, oxidative stress and inflammation. MicroRNAs (miRs) are shown to regulate many biological processes associated with obesity, comprising adipocyte differentiation, insulin action and fat metabolism. In addition, recent studies confirm that miRs are important regulators of mitochondrial function by either directly modulating mitochondrial proteins or targeting mitochondrial regulators, hereby modulating metabolic process in the context of obesity...

BACKGROUND: microRNAs play pivotal roles in metabolism and other aspects of cell biology. microRNA-33 and liver X receptor (LXR) affect lipid metabolism and cholesterol trafficking. In this study, we evaluated effects of co-administration of miR-33 inhibitor and LXR activator on LXR-α and adenosine triphosphate-binding cassette transporter A1 (ABCA1) expression in mice liver. METHODS: Twenty-four mice were randomly allocated into four groups (n = 6). Group 1 mice received standard chow diet without any treatment, group 2 received 30 mg/kg/48 hour LXR agonist (T0901317), group 3 received 1 mg/kg/48 hour in vivo locked nucleic acids (LNA) anti-miR-33 and group 4 received both T0901317 and in vivo LNA anti-miR-33...

The possibility that diet-derived miRNAs survive the gastrointestinal tract and exert biological effects in target cells is triggering considerable research in the potential abilities of alimentary preventive and therapeutic approaches. Many validation attempts have been carried out and investigators disagree on several issues. The barriers exogenous RNAs must surpass are harsh and adequate copies must reach target cells for biological actions to be carried out. This prospect opened a window for previously unlikely scenarios concerning exogenous non-coding RNAs, such as a potential role for breast milk microRNAs in infants' development and maturation...

BACKGROUNDS: The incidence of nonalcoholic fatty liver disease (NAFLD) is rapidly increasing due to the prevalence of obesity. NAFLD is a major risk factor of hepatocellular carcinoma (HCC). Even with successful surgical removal, the presence of NAFLD is associated with an increased recurrence of HCC. Despite the extensive study of NAFLD, its underlying mechanism(s) remains essentially unknown and there are no FDA-approved drugs for its treatment. Alterations in microRNA (miR) expression have been observed in human fatty livers...

Macrophage aging is pathogenic in diseases of the elderly, including age-related macular degeneration (AMD), a leading cause of blindness in older adults. However, the role of microRNAs, which modulate immune processes, in regulating macrophage dysfunction and thereby promoting age-associated diseases is underexplored. Here, we report that microRNA-150 (miR-150) coordinates transcriptomic changes in aged murine macrophages, especially those associated with aberrant lipid trafficking and metabolism in AMD pathogenesis...

The thyroid hormone responsive spot 14 (THRSP) gene is a de novo lipogenesis-related gene that plays a significant role in the initiation and development of nonalcoholic fatty liver disease (NAFLD). Several previous studies had shown that endogenous and environmental factors could regulate the expression of THRSP. The role of microRNAs (miRNAs), however, in controlling THRSP expression has not been investigated. In this study, we first constructed the hepatic steatosis cell model by using a mixture of free fatty acids (FFAs; oleate/palmitate, 2:1 ratio) to treat and demonstrate the promotive role of THRSP in lipid accumulation in hepatic cells...

The loss of muscle size, strength and quality with ageing is a major determinant of morbidity and mortality in the elderly. The regulatory pathways that impact on the muscle phenotype include the translational regulation maintained by microRNAs (miRNA). Yet the miRNAs that are expressed in human skeletal muscle and relationship to muscle size, strength and quality are unknown. Using next-generation sequencing, the 50 most abundantly expressed miRNAs were selected and then analysed in m. vastus lateralis, obtained by biopsy from middle-aged males (n=48; 50...

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) imaging elucidates molecular distributions in tissue sections, providing useful information about the metabolic pathways linked to diseases. However, delocalization of the analytes and inadequate tissue adherence during sample preparation are among some of the unfortunate phenomena associated with this technique due to their role in the reduction of the quality, reliability, and spatial resolution of the ToF-SIMS images. For these reasons, ToF-SIMS imaging requires a more rigorous sample preparation method in order to preserve the natural state of the tissues...

Nonalcoholic fatty liver disease (NAFLD) is characterized by ectopic lipid accumulation and insulin resistance, yet the underlying molecular mechanisms are poorly understood. MiR-190b is thought to play a role in hepatocellular carcinoma by modulating insulin resistance; however, its role in NAFLD remains unknown. Here, we found that miR-190b expression was significantly increased in the liver tissues of patients with NAFLD, compared to normal tissues. Moreover, miR-190b was upregulated in a high-fat diet NAFLD mouse model and a free fatty acid-induced NAFLD cellular model...

MicroRNAs (miRNAs) are non-coding RNAs that function as post-transcriptional gene regulators and that play vital roles controlling lipid metabolism. miR-205 is an important miRNA related to adipogenesis and lipid metabolism. However, little is known about the potential role of miR-205-5p in genetically improved farmed tilapia (GIFT, Oreochromis niloticus). In this study, we used miRanda software to search for potential miR-205-5p target genes and found a lipid-metabolism-related gene called acetyl-CoA carboxylase β (ACACβ)...

Non-alcoholic fatty liver disease (NAFLD) has been considered as a multi-factorial metabolic syndrome (MetS). MicroRNA-375 (MiR-375) was significantly up-regulated in serum of NAFLD patients and the role of miR-375 was addressed as a putative biomarker of NAFLD progression. However, the specific function of miR-375 in the progression of NAFLD is still unclear and the molecular mechanisms underlying NAFLD have yet to be elucidated. Our study aimed at investigating the regulatory role of miR-375 in the molecular mechanisms of the pathogenic progression of NAFLD and to find out whether miR-375 regulates the expression level of adipokines and inflammatory cytokines in NAFLD...

Platelet-derived microparticles (PMPs) have long been known to increase in circulation in the presence of cancer, and have been considered to be cancer promoting by multiple mechanisms including shrouding of circulating tumor cells allowing immune evasion, inducing a procoagulant state associated with increased risk for venous thromboembolic events in cancer patients, and supporting metastatic dissemination by establishment of niches for anchorage of circulating tumor cells. These modes of PMP-enhanced progression of late stage cancer are generally based on the adhesive and procoagulant surfaces of PMPs...

Juvenile rainbow trout (Oncorhynchus mykiss) confined in pairs form social hierarchies in which socially subordinate fish display characteristic traits, including reduced growth rates and altered glucose metabolism. These effects are, in part, mediated by chronically elevated cortisol levels and/or reduced feeding. To determine the effects of social status on lipid metabolism, trout were held in pairs for 4 d, following which organismal and liver-specific indices of lipid metabolism were measured. At the organismal level, circulating triglycerides were elevated in dominant trout, whereas subordinate trout exhibited elevated concentrations of circulating free fatty acids (FFA) and lowered plasma total cholesterol levels...

Oncologic diseases do not behave as isolated entities. Instead, they are based on complex systemic networks involving cell-cell communication between cancerous and healthy cells of the host, which may either facilitate or prevent cancer progression. In addition to cell-cell contacts, cells communicate through secreted factors in a process modulated by ligand concentration, receptor availability and synergy amongst several signaling circuits. Of these secreted factors, exosomes, 30-150 nm membrane vesicles of endocytic origin released by virtually all cells, have emerged as important cell-cell communication players both in physiological and pathological scenarios by being carriers of all the main biomolecules, including lipids, proteins, DNAs, messenger RNAs and microRNA, and performing intercellular transfer of components, locally and systemically...

The endothelial lining can be viewed as the first line of defense against risk factors of vascular disease. Endothelial dysfunction is regarded as an initial event for atherogenesis since defects in vascular integrity and homeostasis are responsible for lipid infiltration and recruitment of monocytes into the vessel wall. Monocytes-turned-macrophages, which possess astounding inflammatory plasticity, perpetuate chronic inflammation and growth of atherosclerotic plaques and, are therefore central for the pathogenesis of atherosclerosis...

OBJECTIVE: Several miR/s that regulate gene/s relevant in atherogenesis are being described. We identified a miR (miR-98) that targets LOX-1, a receptor for ox-LDL, and speculated that it might be relevant in atherogenesis. APPROACH AND RESULTS: MicroRNA-98 was predicted by bioinformatics tools. The effects of miR-98 (by use of mimics and inhibitors) on LOX-1 expression and foam cell formation in mouse peritoneal macrophages were assessed. ApoE-/- mice fed by high fat diet were administered with mmu-agomiR-98 and mmu-antagomiR-98, and expression of LOX-1 and foam cell formation in aorta were quantified...

Exosomes are small (30-150 nm) vesicles of endosomal origin secreted by most cell types. Exosomes contain proteins, lipids, and RNA species including microRNA, mRNA, rRNA, and long noncoding RNAs. The mechanisms associated with exosome synthesis and cargo loading are still poorly understood. A role for exosomes in intercellular communication has been reported in physiological and pathological conditions both in vitro and in vivo. Previous studies have suggested that Schwann cell-derived exosomes regulate neuronal functions, but the mechanisms are still unclear...

Glucose serves as a primary, and for some tissues the unique, fuel source in order to generate and maintain the biological functions. Hyperglycemia is a hallmark of type 2 diabetes and is the direct consequence of perturbations in the glucose homeostasis. Insulin resistance, referred to as a reduced response of target tissues to the hormone, contributes to the development of hyperglycemia. The molecular mechanisms responsible for the altered glucose homeostasis are numerous and not completely understood. MicroRNAs (miRNAs) are now recognized as regulators of the lipid and glucose metabolism and are involved in the onset of metabolic diseases...

The development of new therapeutic strategies to control or reverse hepatic fibrosis requires thorough knowledge about its molecular and cellular basis. It is known that the heptapeptide angiotensin-(1-7) [ang-(1-7)] can reduce hepatic fibrosis and steatosis in vivo; therefore, it is important to uncover the mechanisms regulating its activity and cellular model of investigation. Ang-(1-7) is a peptide of the renin-angiotensin system (RAS), and here we investigated its modulatory effect on the expression pattern of microRNAs (miRNAs) in hepatic stellate cells (HSCs) LX-2, which transdifferentiate into fibrogenic and proliferative cells...

Exosomes are membranous vesicles of 30-150 nm in diameter that are derived from the exocytosis of the intraluminal vesicles of many cell types including immune cells, stem cells, cardiovascular cells and tumor cells. Exosomes participate in intercellular communication by delivering their contents to recipient cells, with or without direct contact between cells, and thereby influence physiological and pathological processes. They are present in various body fluids and contain proteins, nucleic acids, lipids, and microRNAs that can be transported to surrounding cells...