Jiangtang Sanhao formula ameliorates skeletal muscle insulin resistance via regulating GLUT4 translocation in diabetic mice

Scutellarein ameliorates pulmonary arterial hypertension via sirtuin 1 mediated deacetylation of nicotinamide nucleotide transhydrogenase

Scutellarein (Sc), a natural flavonoid, holds potential for treating pulmonary arterial hypertension (PAH), yet its mechanisms remain unexplored. This study investigated Sc's therapeutic effects and underlying pathways in PAH. In vivo experiments demonstrated that Sc significantly attenuated right ventricular hypertension, pulmonary arterial remodeling, αSMA expression, and vascular inflammation in PAH models. In vitro, Sc suppressed hypoxia-induced proliferation, migration, inflammation, and pyroptosis in human pulmonary artery smooth muscle cells (HPASMCs). Mechanistically, Sc activated the SIRT1/NAD+ axis to restore mitochondrial homeostasis: it upregulated SIRT1 expression and elevated NAD+ levels by promoting SIRT1-mediated deacetylation of nicotinamide nucleotide transhydrogenase (NNT), thereby enhancing NNT activity. Elevated NAD+ further activated SIRT1, forming a self-reinforcing SIRT1/NNT/NAD+ feedback loop that mitigated hypoxia-induced mitochondrial dysfunction. This study identifies Sc as a novel regulator of the SIRT1-dependent NNT deacetylation pathway, which stabilizes NAD+ homeostasis to counteract HPASMCs dysregulation in PAH. These findings highlight Sc's potential as a therapeutic candidate for PAH, offering insights into targeting mitochondrial-metabolic pathways for vascular remodeling diseases.

Self-Nanoemulsifying Formulation Improves Oral Bioavailability and Insulin Sensitizing Potency of Formononetin-Vitamin E Conjugate in Type 2 Diabetic Mice

The escalating incidence of obesity, diabetes, and insulin resistance has become a significant global health concern. In this study, we have developed a self-nanoemulsifying delivery system (SNEDS) of formononetin-vitamin E conjugate (VESylated-FMN) for improving its oral bioavailability and improving insulin sensitivity and glycemic control. The developed SNEDS were characterized using dynamic light scattering and transmission electron microscopy. Thereafter, the loading capacity, in vitro release, thermodynamic, and gastrointestinal stability of the developed formulation were evaluated. The safety and oral bioavailability of VESylated-FMN-SNEDS were assessed in Sprague-Dawley rats, whereas insulin-sensitizing potency was assessed in high-fat diet-induced type 2 diabetic mice. The VESylated-FMN-SNEDS quickly emulsified on dilution (droplet size ∼79.17 nm) and showed remarkable thermodynamic and gastrointestinal stability. The developed formulation demonstrated enhanced oral bioavailability (∼1.3-fold higher AUC0-t) of VESylated-FMN without liver and kidney injury. Consequently, VESylated-FMN-SNEDS significantly improves insulin sensitivity and glycemic control in HFD-fed mice compared to VESylated-FMN by upregulating the transcript level of insulin-sensitizing genes. Therefore, the SNEDS formulation could be an effective strategy to augment the oral bioavailability and insulin-sensitizing potency of VESylated-FMN.

Jiang Tang San Hao Formula exerts its anti-diabetic effect by affecting the gut-microbiota-brain axis

BACKGROUND

Type 2 diabetes is a complex metabolic disorder characterized by insulin resistance and impaired insulin secretion, with growing evidence highlighting the critical role of the gut-microbiota-brain axis in modulating glucose and lipid metabolism.

OBJECTIVE

To evaluate the effects of Jiang Tang San Hao Formula (JTSHF) on blood glucose control in type 2 diabetic mouse model and to explore its mechanism through the gut- microbiota-brain axis.

METHODS

A type 2 diabetes model was established using six-week-old male C57BL6/J mice, induced by a high-fat diet combined with streptozotocin injection. The diabetic mice then randomly assigned to the model group, metformin (Glucophage) group and JTSHF group, receiving 11 weeks of treatment by gavage. Body weight and fasting blood glucose were monitored biweekly. The oral glucose tolerance test was performed during the fifth and 10th weeks of the intervention. The measurements of body composition were conducted pre- and post-treatment. After the intervention, serum insulin, lipid levels, glucagon like peptide-1 (GLP-1), peptide YY, ghrelin, and leptin were detected. The fresh feces of mice were collected before sacrifice for gut microbiota analysis and short chain fatty acids quantification. The colon tissues of mice in each group were collected to observe the morphological structure and to measure the expression levels of GPR41 and GPR43. The hypothalamus was collected to assess the expression of POMC, AgRP and NPY.

RESULTS

JTSHF significantly boosted sugar and lipid metabolism and contributed to weight reduction in diabetic mice (p < 0.05). At the genus level, JTSHF increased the relative abundance of Bacteroides, Prevotella, and Parabacteroides, and decreased Clostridium, Lactobacillus, and Oscillibacter in the gut microbiota. JTSHF enhanced the content of short chain fatty acids, improved the expression level of GPR43/41 in colonic tissue (p < 0.05), and increased POMC expression while decreasing AgRP and NPY expression in the hypothalamus (p < 0.05). Serum GLP-1 was increased, and ghrelin was decreased significantly after JTSHF intervention (p < 0.05).

CONCLUSION

By affecting the composition, relative abundance, and metabolites of gut microbiota, JTSHF regulates various gut brain peptides, affects the hypothalamic feeding center, improves glucose and lipid metabolism, and thus plays the anti-diabetic role. The study provides novel insights into how traditional Chinese medicine modulates the gut-brain connection to exert anti-diabetic effects, highlighting the innovative potential of JTSHF in metabolic disease management.

The role of AMPKα subunit in Alzheimer's disease: In-depth analysis and future prospects

The AMP-activated protein kinase α (AMPKα) subunit is the catalytic subunit in the AMPK complex, playing a crucial role in AMPK activation. It has two isoforms: AMPKα1 and AMPKα2. Emerging evidence suggests that the AMPKα subunit exhibits subtype-specific effects in Alzheimer's disease (AD). This review discusses the role of the AMPKα subunit in the pathogenesis of AD, including its impact on β-amyloid (Aβ) pathology, Tau pathology, metabolic disorders, inflammation, mitochondrial dysfunction, inflammasome and pyroptosis. Additionally, it reviews the distinct roles of its isoforms, AMPKα1 and AMPKα2, in AD, which may provide more precise targets for future drug development in AD.

Histone deacetylase functions and therapeutic implications for adult skeletal muscle metabolism

Skeletal muscle is a highly adaptive organ that sustains continuous metabolic changes in response to different functional demands. Healthy skeletal muscle can adjust fuel utilization to the intensity of muscle activity, the availability of nutrients and the intrinsic characteristics of muscle fibers. This property is defined as metabolic flexibility. Importantly, impaired metabolic flexibility has been associated with, and likely contributes to the onset and progression of numerous pathologies, including sarcopenia and type 2 diabetes. Numerous studies involving genetic and pharmacological manipulations of histone deacetylases (HDACs) in vitro and in vivo have elucidated their multiple functions in regulating adult skeletal muscle metabolism and adaptation. Here, we briefly review HDAC classification and skeletal muscle metabolism in physiological conditions and upon metabolic stimuli. We then discuss HDAC functions in regulating skeletal muscle metabolism at baseline and following exercise. Finally, we give an overview of the literature regarding the activity of HDACs in skeletal muscle aging and their potential as therapeutic targets for the treatment of insulin resistance.