Molecular Mechanisms of the Anti-obesity Properties of Agardhiella subulata in Mice Fed a High-Fat Diet

Low-methoxy-pectin and chlorogenic acid synergistically promote lipolysis and β-oxidation by regulating AMPK signaling pathway in obese mice

Chlorogenic acid (CGA) displays various biological activities in preventing high-calorie diet-induced metabolic complications. The absorption efficiency of CGA in the stomach and small intestine is relatively low, with approximately 70 % of CGA being metabolized by colonic microorganisms before it enters the bloodstream. In this study, we successfully developed CGA-LMP (Low-methoxy-pectin) conjugates to improve the absorption rate of CGA. C57BL/6J mice were fed high-fat diets (HFD) supplemented with CGA, LMP, or CGA-LMP conjugates for a duration of eight weeks. The results demonstrated that the CGA, LMP, or CGA-LMP conjugates prevented HFD-induced hyperlipidemia, inflammation, liver steatosis, and adipocyte hypertrophy in obese mice. Notably, the CGA-LMP conjugates demonstrated superior efficacy in alleviating obesity compared to CGA or LMP alone. Further studies revealed that the primary mechanism of weight loss was the activation of the AMPK signaling pathway, which facilitates lipolysis and lipid β-oxidation. These findings highlight that the enhanced the anti-obesity effectiveness of CGA-LMP conjugates, expanding their potential applications in the field of functional nutrition and foods.

Aloe polysaccharides ameliorate obesity-associated cognitive dysfunction in high-fat diet-fed mice by targeting the gut microbiota and intestinal barrier integrity

Aloe polysaccharides (APs) display cognition-improving properties, but the underlying mechanisms remain unclear. Herein, AP supplementation for 24 weeks significantly improved cognitive behavioral disturbances caused by a high-fat diet. Moreover, APs notably reshaped the structure of the gut microbiota, which was manifested by increasing the relative abundance of Alloprevotella, Alistipes, Romboutsia, Turicibacter, Prevotellaceae_UCG-001, and Akkermansia while reducing the abundance of Parasutterella, Staphylococcus, Helicobacter, Enterococcus, and Erysipelatoclostridium. Notably, the gut barrier damage and LPS leakage caused by HF were recovered by APs. Additionally, with the improvement of intestinal barrier integrity, oxidative stress and inflammation in the brain and jejunum were significantly ameliorated. Furthermore, the expression of genes associated with cognitive impairment and the intestinal tract barrier was up-regulated (CREB, BDNF, TrkB, ZO-1 and occludin), while the expression of genes associated with inflammatory factors was down-regulated (IL-1β, IL-6, and TNF-α). Finally, we observed a significant correlation among cognition-related genes, gut microbiota, oxidative stress, and inflammation in the HF-AP group. Together, our findings suggest that altered gut microbiota composition and improved gut barrier integrity may be important targets for potentially improving high-fat diet-induced cognitive impairment.

Dietary Methionine Restriction Promotes Fat Browning and Attenuates Hepatic Lipid Accumulation in High-Choline-Fed Mice Associated with the Improvement of Thyroid Function

This study aims to explore the influences of a methionine-restricted diet (MRD) on fat browning and hepatic lipid accumulation in mice fed with a high-choline diet (HCD) and their possible mechanisms. ICR mice were randomly divided into three groups and fed with a normal diet (0.86% methionine + 0.20% choline, ND), HCD (0.86% methionine + 1.20% choline), or MRD (0.17% methionine + 1.20% choline) for 90 consecutive days. We found that MRD reduced body weight and fat mass; increased heat production and ambulatory locomotor activity; reduced hepatic and plasma lipid levels, hepatic fatty infiltration area, and adipocyte volume in white and brown adipose tissue; promoted fat browning, especially upregulated gene and protein expression levels of uncoupling protein 1 (UCP1); and promoted fat catabolism and inhibited fat anabolism in the liver and adipose tissue. Moreover, MRD increased antioxidant defenses and reduced inflammatory cytokine levels in the thyroid, blood, and liver. Furthermore, MRD improved thyroid morphological structure, promoted the synthesis and secretion of thyroid hormones, and enhanced the actions of thyroid hormones on its receptor organs (liver and adipose tissue). These findings suggested that MRD promoted fat browning and attenuated hepatic lipid accumulation in HCD mice associated with the improvement of thyroid function.

Ethanolic extract of root from Arctium lappa L ameliorates obesity and hepatic steatosis in rats by regulating the AMPK/ACC/CPT-1 pathway

Burdock (Arctium lappa L) root is eaten as a vegetable in many countries and used as an ethnomedicine because of its various pharmacological effects. The objective of this study was to investigate the underlying mechanisms of ethanolic extract of root from Arctium lappa L root (ALE) to lose weight and regulate lipid metabolism. The results showed that ALE can regulate lipid metabolism level and inhibit the weight gain of rats induced by the high-sugar and high-fat diet. The contents of triglyceride and cholesterol in the liver of obese rats significantly reduced, and hepatic steatosis was ameliorated. In addition, this study identified that ALE enhanced hepatic fatty acid β-oxidation and ameliorated hepatic steatosis by activating AMPK/ACC/CPT-1 pathway. These results indicated that ALE has a potential preventive and therapeutic effect on metabolic-associated fatty liver disease and obesity. PRACTICAL APPLICATIONS: Obesity is already a global health problem. Obesity causes accumulation of triglycerides, which leads to hepatic steatosis. Long-term steatosis causes liver damage and metabolic fatty liver disease. Plant-derived functional foods or herbal medicines have better effects on weight loss and liver protection, which are more conducive to long-term use with less toxic side effects. As a medicinal and edible plant material, Arctium lappa L root has the effect in losing weight. Our study showed that ethanolic extract of Arctium lappa L root effectively regulates lipid metabolism and inhibits hepatic steatosis. Arctium lappa L root may be used as a therapeutic drug and functional food raw material for obesity and fatty liver disease.

Astaxanthin From Haematococcus pluvialis Prevents High-Fat Diet-Induced Hepatic Steatosis and Oxidative Stress in Mice by Gut-Liver Axis Modulating Properties

Scope

Evidence is mounting that astaxanthin (ATX), a xanthophyll carotenoid, used as a nutritional supplement to prevent chronic metabolic diseases. The present study aims to identify the potential function of ATX supplementation in preventing steatohepatitis and hepatic oxidative stress in diet-induced obese mice.

Methods and Results

In this study, ATX as dose of 0.25, 0.5, and 0.75% have orally administered to mice along with a high-fat diet (HFD) to investigate the role of ATX in regulating liver lipid metabolism and gut microbiota. The study showed that ATX dose-dependently reduces body weight, lipid droplet formation, hepatic triglycerides and ameliorated hepatic steatosis and oxidative stress. 0.75% ATX altered the levels of 34 lipid metabolites related to hepatic cholesterol and fatty acid metabolism which might be associated with downregulation of lipogenesis-related genes and upregulation of bile acid biosynthesis-related genes. The result also revealed that ATX alleviates HFD-induced gut microbiota dysbiosis by significantly inhibiting the growth of obesity-related Parabacteroides and Desulfovibrio while promoting the growth of Allobaculum and Akkermansia.

Conclusion

The study results suggested that dietary ATX may prevent the development of hepatic steatosis and oxidative stress with the risk of metabolic disease by gut-liver axis modulating properties.

Pyrolysis of marine algae for biochar production for adsorption of Ciprofloxacin from aqueous solutions

Biochars derived from three species of algae was synthesized by impregnating the green algae Ulva Ohnoi, red algae Agardhiella subulata, and brown algae Sargassum hemiphyllum with ZnCl₂ chemical activator and employed as a long-term adsorbent for ciprofloxacin (CIP) removal from water. The results revealed that combination of brown algae and ZnCl₂ chemical activator (ZBAB) successfully produced mesoporous biochar with excellent physicochemical characteristics and gave the best CIP adsorption capacity. The ZBAB yielded a high CIP adsorption capacity (190-300 mg g^-1) under various parameter effects (initial pH, temperature and major ions). Throughought the surface characterization techniques, the proposed adsorption mechanisms were electrostatic interaction, π-π EDA interaction, pore filling and hydrogen bonding. Moreover, not only algal biochars exhibited innovative and potential adsorbent for rapid and effective remediate pollution from water, but combination of algal biomass and ZnCl₂ activator also created renewable source of energy from biomass pyrolysis.