Chrysin Stimulates Subcutaneous Fat Thermogenesis in Mice by Regulating PDGFRα and MicroRNA Expressions

A narrative review on the mechanism of natural flavonoids in improving glucolipid metabolism disorders

Glucolipid metabolism disorder (GLMD) is a complex chronic disease characterized by glucose and lipid metabolism disorders with a complex and diverse etiology and rapidly increasing incidence. Many studies have identified the role of flavonoids in ameliorating GLMD, with mechanisms related to peroxisome proliferator-activated receptors, nuclear factor kappa-B, AMP-activated protein kinase, nuclear factor (erythroid-derived 2)-like 2, glucose transporter type 4, and phosphatidylinositol-3-kinase/protein kinase B pathway. However, a comprehensive summary of the flavonoid effects on GLMD is lacking. This study reviewed the roles and mechanisms of natural flavonoids with different structures in the treatment of GLMD reported globally in the past 5 years and provides a reference for developing flavonoids as drugs for treating GLMD.

The Effects of Crataegus pinnatifida and Wolfiporia extensa Combination on Diet-Induced Obesity and Gut Microbiota

Obesity is a multifactorial chronic metabolic disease with multiple complications. Crataegus pinnatifida (CP) and Wolfiporia extensa (WE) are traditional functional foods with improving metabolic health properties. This study demonstrated the effect of CP and WE combination on ameliorating obesity induced by a high-fat diet (HFD). Moreover, the CP-WE food pair ameliorated HFD-induced metabolic disorders, including glucose intolerance, insulin resistance, hyperlipidemia, and hepatic steatosis. 16S rRNA gene amplicon sequencing and analysis revealed that CP combined with WE reshaped the composition of gut microbiota in HFD-fed mice. Furthermore, correlation analysis revealed a substantial association between the obesity-related parameters and the shifts in predominant bacterial genera influenced by the food pair intervention. In conclusion, this study demonstrated that the CP-WE food pair ameliorated HFD-induced obesity and reshaped gut microbiota composition, providing a promising approach to combat obesity through specific food combinations.

Fuziline Ameliorates Glucose and Lipid Metabolism by Activating Beta Adrenergic Receptors to Stimulate Thermogenesis

Radix aconiti carmichaeli is a widely used traditional Chinese medicine that has been found to be effective in treating cardiovascular diseases and metabolic disorders. Patients with these diseases often experience a heat generation disorder, which is characterized by chilliness and can worsen the progression of the disease. This study established an in vitro screening model combining the examination of cellular mitochondrial membrane potential and mitochondrial temperature to screen drugs with thermogenic activity. After differentiation and determination of the content of characteristic metabolites of the drug-containing serum blood components, it was found that Fuziline (FZL) is the key thermogenic property in Radix aconiti carmichaeli, responsible for its thermogenic effects with a high relative importance of 33%. Experiments were conducted to evaluate the thermogenic activity of Radix aconiti carmichaeli and FZL in vivo by assessing temperature changes in various organs, including the rectum, liver, and brown adipose tissue. Moreover, the effects of intracellular β3-adrenergic receptor (β3-AR) agonistic effects were evaluated using transient β3-AR transfection and dual-luciferase assay systems. The molecular mechanism by which FZL promotes thermogenesis and improves mitochondrial function was investigated by verifying the β-adrenergic receptors (β-AR) downstream signaling pathway. The results suggest that FZL activates β-AR nonselectively, which in turn activates the downstream cAMP-PKA signaling pathway and leads to an increase in liver glycogenolysis and triglyceride hydrolysis, accompanied by enhancing mitochondrial energy metabolism. Consequently, the liver and brown adipose tissue receive energy to generate heat. In summary, these findings provide insight into the therapeutic application of Radix aconiti carmichaeli for metabolic disorders associated with heat generation disorders.

The activity comparison of six dietary flavonoids identifies that luteolin inhibits 3T3-L1 adipocyte differentiation through reducing ROS generation

Mitochondrial reactive oxygen species (ROS)generation plays an essential role in the process of adipocyte differentiation and is involved in the development of obesity and associated metabolic diseases. Various dietary flavonoids possess the substantial anti-adipogenic activity. However, it is unclear whether these flavonoids inhibit adipocyte differentiation by reducing ROS generation. In this study, the effects of six common dietary flavonoids on adipocyte differentiation were assessed in 3T3-L1 cells. The flavonoids with the same backbone of 5,7-dihydroxylflavone, including flavones apigenin, chrysin, luteolin and flavonols kaempferol, myricetin, quercetin, dose-dependently inhibited 3T3-L1 adipocyte differentiation, suggesting an associated hierarchy of inhibitory capability: luteolin > quercetin > myricetin > apigenin/kaempferol > chrysin. Meanwhile, six flavonoids were found to inhibit adipogenic gene expression and the early stage of adipocyte differentiation. Among the tested flavonoids, luteolin significantly reduced both intracellular and mitochondrial ROS generation during adipocyte differentiation. Further, luteolin treatment depressed the elevation of H₂O₂ concentration in the early stage of 3T3-L1 differentiation and reversed the facilitated effects of exogenous H₂O₂ on 3T3-L1 adipocyte differentiation and ROS generation. Altogether, the activity comparison of six dietary flavonoids identifies that luteolin inhibits 3T3-L1 adipocyte differentiation through reducing ROS generation, elucidating a new mechanism underlying the anti-adipogenic actions of flavonoids.

Nutritional activities of luteolin in obesity and associated metabolic diseases: an eye on adipose tissues

Obesity is characterized by excessive body fat accumulation and is a high-risk factor for metabolic comorbidities, including type 2 diabetes, nonalcoholic fatty liver disease, and cardiovascular disease. In lean individuals, adipose tissue (AT) is not only an important regulatory organ for energy storage and metabolism, but also an indispensable immune and endocrine organ. The sustained energy imbalance induces adipocyte hypotrophy and hyperplasia as well as AT remodeling, accompanied by chronic low-grade inflammation and adipocytes dysfunction in AT, ultimately leading to systemic insulin resistance and ectopic lipid deposition. Luteolin is a natural flavonoid widely distributed in fruits and vegetables and possesses multifold biological activities, such as antioxidant, anticancer, and anti-inflammatory activities. Diet supplementation of this flavonoid has been reported to inhibit AT lipogenesis and inflammation as well as the ectopic lipid deposition, increase AT thermogenesis and systemic energy expenditure, and finally improve obesity and associated metabolic diseases. The purpose of this review is to reveal the nutritional activities of luteolin in obesity and its complications with emphasis on its action on AT energy metabolism, immunoregulation, and endocrine intervention.

Factors Associated with White Fat Browning: New Regulators of Lipid Metabolism

Mammalian adipose tissue can be divided into white and brown adipose tissue based on its colour, location, and cellular structure. Certain conditions, such as sympathetic nerve excitement, can induce the white adipose adipocytes into a new type of adipocytes, known as beige adipocytes. The process, leading to the conversion of white adipocytes into beige adipocytes, is called white fat browning. The dynamic balance between white and beige adipocytes is closely related to the body’s metabolic homeostasis. Studying the signal transduction pathways of the white fat browning might provide novel ideas for the treatment of obesity and alleviation of obesity-related glucose and lipid metabolism disorders. This article aimed to provide an overview of recent advances in understanding white fat browning and the role of BAT in lipid metabolism.

Aptamer-Functionalized Binary-Drug Delivery System for Synergetic Obesity Therapy

The targeted delivery of phytochemicals that promote energy expenditure for obesity therapy remains a challenge. This study assembled a functionalized adipo-8 aptamer loaded with allicin using isothermal rolling-circle techniques to form a synergistic adipocyte-targeted binary-drug delivery system for treating obesity. The functionalized adipo-8 aptamer efficiently protected allicin from adsorption, showing significant potential to encapsulate, transport, and release molecular cargos into white adipose tissue. Introducing the negatively charged allicin, a phytochemical able to induce adipose tissue browning, reduced the diameters of DNA-nanoflower from 770 to 380 nm and increased cellular uptake efficiency up to 118.7%. The intracellular distribution observed via confocal microscopy confirmed the successful receptor recognition mediated by aptamers in the DNA-nanoflower-allicin (NFA) framework as well as its excellent stability to escape from lysosomes. In vivo results demonstrated that subcutaneous administration of NFA effectively promoted adipocyte browning and systematic energy expenditure with minimal side effects. Furthermore, the G-quadruplex in the mitochondrial uncoupling protein-1 promoter was found to be an interactive allicin target for regulating thermogenesis to combat obesity.