Management of Obesity and Obesity-Related Disorders: From Stem Cells and Epigenetics to Its Treatment

Circulating Selenium Level Was Positively Related to Visceral Adiposity Index with a Non-linear Trend: a Nationwide Study of the General Population

Selenium plays a role in obesity. However, whether circulating selenium levels are related to the visceral adiposity index (VAI), an indicator of obesity, is still unknown. Based on the National Health and Nutrition Examination Survey (NHANES) 2011-2018, data from 12,777 individuals aged ≥ 20 years were analyzed to clarify this question. In fully adjusted models of multivariate regression analysis, natural logarithm (Ln) selenium was positively related to Ln VAI (β = 0.41; 95% confidence interval [CI], 0.27, 0.55; P < 0.001). Compared with the lowest quartile of Ln selenium, the highest quartile was also positively associated with Ln VAI (β = 0.16; 95% CI, 0.11, 0.21; P < 0.001). Moreover, we found that this positive connection was non-linear. When Ln selenium was less than the inflection point, Ln selenium was positively related to Ln VAI (β = 0.41; 95% CI, 0.31, 0.52; P < 0.001). However, when Ln selenium was greater than or equal to the inflection point, Ln selenium was not significantly related to Ln VAI (β = -0.15; 95% CI, -0.56, 0.25; P = 0.455). In subgroup analysis, significant interactions were observed with age and sex (P for interaction < 0.05). Stronger interactions were observed among middle-aged participants (β = 0.65; 95% CI, 0.31, 0.98; P = 0.002) and males (β = 0.61; 95% CI, 0.43, 0.79; P < 0.001). Overall, circulating selenium levels were positively related to VAI, with a non-linear trend. Prospective studies and interventional experiments are necessary to verify the possible mechanisms.

The Circulating Selenium Concentration Is Positively Related to the Lipid Accumulation Product: A Population-Based Cross-Sectional Study

The lipid accumulation product (LAP) is a reliable marker of metabolic syndrome, which includes conditions like obesity. However, the correlation between the circulating selenium (CSe) concentration and the LAP is currently unclear. This study aimed to ascertain this correlation. Overall, 12,815 adults aged ≥20 years were enrolled in this study. After adjusting for all the confounding variables, CSe was positively correlated to the LAP (β = 0.41; 95% confidence interval [CI]: 0.28, 0.54; p < 0.001). Compared with the lowest quartile of CSe, the highest quartile of CSe was positively related to the LAP (β = 0.16; 95% CI: 0.12, 0.21; p < 0.001). Moreover, the correlation between CSe and the LAP revealed a positive non-linear trend. In the subgroup analysis, interaction effects were observed for age, sex, smoking, and stroke (p for interaction < 0.05). The effects were stronger for males (β = 0.64, 95% CI: 0.47, 0.80; p < 0.001) and individuals who smoke at the time of the trial (β = 0.64, 95% CI: 0.37, 0.91; p < 0.001). In conclusion, our results indicated that CSe was positively correlated with the LAP in a non-linear manner. Future research is warranted to explore their relationship and better understand the mechanisms underlying this association.

AMP-activated protein kinase activation suppresses leptin expression independently of adipogenesis in primary murine adipocytes

Adipogenesis, defined as the development of mature adipocytes from stem cell precursors, is vital for the expansion, turnover and health of adipose tissue. Loss of adipogenic potential in adipose stem cells, or impairment of adipogenesis is now recognised as an underlying cause of adipose tissue dysfunction and is associated with metabolic disease. In this study, we sought to determine the role of AMP-activated protein kinase (AMPK), an evolutionarily conserved master regulator of energy homeostasis, in adipogenesis. Primary murine adipose-derived stem cells were treated with a small molecule AMPK activator (BI-9774) during key phases of adipogenesis, to determine the effect of AMPK activation on adipocyte commitment, maturation and function. To determine the contribution of the repression of lipogenesis by AMPK in these processes, we compared the effect of pharmacological inhibition of acetyl-CoA carboxylase (ACC). We show that AMPK activation inhibits adipogenesis in a time- and concentration-dependent manner. Transient AMPK activation during adipogenic commitment leads to a significant, ACC-independent, repression of adipogenic transcription factor expression. Furthermore, we identify a striking, previously unexplored inhibition of leptin gene expression in response to both short-term and chronic AMPK activation irrespective of adipogenesis. These findings reveal that in addition to its effect on adipogenesis, AMPK activation switches off leptin gene expression in primary mouse adipocytes independently of adipogenesis. Our results identify leptin expression as a novel target of AMPK through mechanisms yet to be identified.

Roles of protein post-translational modifications in glucose and lipid metabolism: mechanisms and perspectives

The metabolism of glucose and lipids is essential for energy production in the body, and dysregulation of the metabolic pathways of these molecules is implicated in various acute and chronic diseases, such as type 2 diabetes, Alzheimer's disease, atherosclerosis (AS), obesity, tumor, and sepsis. Post-translational modifications (PTMs) of proteins, which involve the addition or removal of covalent functional groups, play a crucial role in regulating protein structure, localization function, and activity. Common PTMs include phosphorylation, acetylation, ubiquitination, methylation, and glycosylation. Emerging evidence indicates that PTMs are significant in modulating glucose and lipid metabolism by modifying key enzymes or proteins. In this review, we summarize the current understanding of the role and regulatory mechanisms of PTMs in glucose and lipid metabolism, with a focus on their involvement in disease progression associated with aberrant metabolism. Furthermore, we discuss the future prospects of PTMs, highlighting their potential for gaining deeper insights into glucose and lipid metabolism and related diseases.

Multimodal Strategies to Fight Obesity: Research on Tailored Therapies Based on Natural and Synthetic Compounds for Prevention, Management and Treatment

In the past 50 years, the global prevalence of obesity and overweight has tripled, reaching pandemic proportions and blatantly representing an urgent problem for public health [...].