Physiology (Bethesda)
March 2025
Brown adipose tissue (BAT) thermogenesis results from the uncoupling of mitochondrial inner membrane proton gradient mediated by uncoupling protein 1 (UCP-1), which is activated by lipolysis-derived fatty acids. Norepinephrine (NE) secreted by sympathetic innervation not only activates BAT lipolysis and UCP-1 but, uniquely in brown adipocytes, promotes "futile" metabolic cycles and enhances BAT thermogenic capacity by increasing UCP-1 content, mitochondrial biogenesis, and brown adipocyte hyperplasia. NE exerts these actions by triggering signaling in the canonical G protein-coupled β-adrenergic receptors, cAMP, and protein kinase A (PKA) pathway, which in brown adipocytes is under a complex and intricate cross talk with important growth-promoting signaling pathways such as those of mechanistic target of rapamycin (mTOR) complexes 1 (mTORC1) and 2 (mTORC2).
View Article and Find Full Text PDFFree Radic Res
May 2024
Selenium-containing compounds have emerged as promising treatment for redox-based and inflammatory diseases. This study aimed to investigate the and anti-inflammatory activity of a novel diselenide named as dibenzyl[diselanediyIbis(propane-3-1diyl)] dicarbamate (DD). DD reacted with HOCl ( = 9.
View Article and Find Full Text PDFMol Cell Endocrinol
December 2023
Chloroquine diphosphate (CQ), a weak base used to inhibit autophagic flux and treat malaria and rheumatoid diseases, has been shown, through unknown mechanisms, to improve glucose and lipid homeostasis in patients and rodents. We investigate herein the molecular mechanisms underlying these CQ beneficial metabolic actions in diet-induced obese mice. For this, C57BL6/J mice fed with either a chow or a high-fat diet (HFD) and uncoupling protein 1 (UCP-1) KO and adipocyte Atg7-deficient mice fed with a HFD were treated or not with CQ (60 mg/kg of body weight/day) during 8 weeks and evaluated for body weight, adiposity, glucose homeostasis and brown and white adipose tissues (BAT and WAT) UCP-1 content.
View Article and Find Full Text PDFAmyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive loss of motor neurons, systemic hypermetabolism, and inflammation. In this context, oxylipins have been investigated as signaling molecules linked to neurodegeneration, although their specific role in ALS remains unclear. Importantly, most methods focused on oxylipin analysis are based on low-resolution mass spectrometry, which usually confers high sensitivity, but not great accuracy for molecular characterization, as provided by high-resolution MS (HRMS).
View Article and Find Full Text PDFHepatocellular carcinoma (HCC) markedly enhances liver secretion of fibroblast growth factor 21 (FGF-21), a hepatokine that increases brown and subcutaneous inguinal white adipose tissues (BAT and iWAT, respectively) uncoupling protein 1 (UCP-1) content, thermogenesis and energy expenditure. Herein, we tested the hypothesis that an enhanced BAT and iWAT UCP-1-mediated thermogenesis induced by high levels of FGF-21 is involved in HCC-associated catabolic state and fat mass reduction. For this, we evaluated body weight and composition, liver mass and morphology, serum and tissue levels of FGF-21, BAT and iWAT UCP-1 content, and thermogenic capacity in mice with Pten deletion in hepatocytes that display a well-defined progression from steatosis to steatohepatitis (NASH) and HCC upon aging.
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