Life metabolism最新文献

Graphical Abstract Lipoprotein lipase (LPL) mediates peripheral tissue triglyceride (TG) uptake. Hepatic ANGPTL3 (A3) and ANGPTL8 (A8) form a complex and inhibit LPL activity in the white adipose tissue (WAT) via systematic circulation. ANGPTL4 (A4) is expressed in WAT and inhibits LPL activity locally. Feeding increases hepatic A8 expression and increases its inhibition for WAT LPL activity together with A3, while feeding suppresses WAT A4 expression and releases its inhibition on LPL. At room temperature, the feeding-suppressed A4 overrides the feeding-increased A3/A8, resulting in increased LPL activity in WAT by food intake. Browning improves hepatic insulin sensitivity and increases postprandial A8 expression. The feeding-increased A3/A8 overrides the feeding-suppressed A4, resulting in suppressed LPL activity in WAT by food intake. This reprogrammed LPL regulation plays an important role in reprogramming TG metabolism during adipose tissue browning.

Graphical Abstract.

Abdominal aortic aneurysm (AAA) is strongly correlated with obesity, partially due to the abnormal expansion of abdominal perivascular adipose tissue (PVAT). Cell death-inducing DNA fragmentation factor-like effector C (CIDEC), also known as fat-specific protein 27 (FSP27) in rodents, is specifically expressed in adipose tissue where it mediates lipid droplet fusion and adipose tissue expansion. Whether and how CIDEC/FSP27 plays a role in AAA pathology remains elusive. Here, we show that FSP27 exacerbates obesity and angiotensin Ⅱ (Ang Ⅱ)-induced AAA progression. FSP27 deficiency in mice inhibited high-fat diet-induced PVAT expansion and inflammation. Both global and adipose tissue-specific FSP27 ablation significantly decreased obesity-related AAA incidence. Deficiency of FSP27 in adipocytes abrogated matrix metalloproteinase-12 (MMP12) expression in aortic tissues. Infiltrated macrophages, which partially colocalize with MMP12, were significantly decreased in the FSP27-deficient aorta. Mechanistically, knockdown of Fsp27 in 3T3-L1 adipocytes inhibited C-C motif chemokine ligand 2 (CCL2) expression and secretion through a c-Jun N-terminal kinase (JNK)-dependent pathway, thereby leading to reduced induction of macrophage migration, while Cidec overexpression rescued this effect. Overall, our study demonstrates that CIDEC/FSP27 in adipose tissue contributes to obesity-related AAA formation, at least in part, by enhancing PVAT inflammation and macrophage infiltration, thus shedding light on its significance as a key regulator in the context of obesity-related AAA.

Type 2 diabetes mellitus (T2DM) is closely associated with obesity, while interactions between the two diseases remain to be fully elucidated. To this point, we offer this perspective to introduce a set of new insights into the interpretation of T2DM spanning the etiology, pathogenesis, and treatment approaches. These include a definition of T2DM as an energy surplus-induced diabetes characterized by the gradual decline of β cell insulin secretion function, which ultimately aims to prevent the onset of severe obesity through mechanisms of weight loss. The body employs three adaptive strategies in response to energy surplus: the first one is adipose tissue expansion to store the energy for weight gain under normal weight conditions; the second one is insulin resistance to slow down adipose tissue expansion and weight gain under overweight conditions; and the third one is the onset of T2DM following β cell failure to reverse the weight gain in obese conditions. The primary signaling molecules driving the compensatory responses are adenosine derivatives, such as adenosine triphosphate (ATP), acetyl coenzyme A (acetyl-CoA), and reduced nicotinamide adenine dinucleotide (NADH). These molecules exert their effects through allosteric, post-translational, and transcriptional regulation of metabolic pathways. The insights suggest that insulin resistance and T2DM are protective mechanisms in the defense against excessive adiposity to avert severe obesity. The perspective provides a unified framework explaining the interactions between the two diseases and opens new avenues in the study of T2DM.

Understanding sex disparities in modifiable risk factors across the lifespan is essential for crafting individualized intervention strategies. We aim to investigate age-related sex disparity in cardiometabolic phenotypes in a large nationwide Chinese cohort. A total of 254,670 adults aged 40 years or older were selected from a population-based cohort in China. Substantial sex disparities in the prevalence of metabolic diseases were observed across different age strata, particularly for dyslipidemia and its components. Generalized additive models were employed to characterize phenotype features, elucidating how gender differences evolve with advancing age. Half of the 16 phenotypes consistently exhibited no sex differences, while four (high-density lipoprotein [HDL] cholesterol, apolipoprotein A1, diastolic blood pressure, and fasting insulin) displayed significant sex differences across all age groups. Triglycerides, apolipoprotein B, non-HDL cholesterol, and total cholesterol demonstrated significant age-dependent sex disparities. Notably, premenopausal females exhibited significant age-related differences in lipid levels around the age of 40-50 years, contrasting with the relatively stable associations observed in males and postmenopausal females. Menopause played an important but not sole role in age-related sex differences in blood lipids. Sleep duration also had an age- and sex-dependent impact on lipids. Lipidomic analysis and K-means clustering further revealed that 58.6% of the 263 measured lipids varied with sex and age, with sphingomyelins, cholesteryl esters, and triacylglycerols being the most profoundly influenced lipid species by the combined effects of age, sex, and their interaction. These findings underscore the importance of age consideration when addressing gender disparities in metabolic diseases and advocate for personalized, age-specific prevention and management.