Fuzhuan brick tea extract prevents diet-induced obesity via stimulation of fat browning in mice

Gracilaria chorda attenuates obesity-related muscle wasting through activation of SIRT1/PGC1α in skeletal muscle of mice

Gracilaria chorda (GC) is a red algal species that is primarily consumed in Asia. Here, we investigated the effect of GC on obesity-related skeletal muscle wasting. Furthermore, elucidating its impact on the activation of sirtuin 1 (SIRT1)/peroxisome proliferator-activated receptor gamma coactivator 1α (PGC1α) constituted a critical aspect in understanding the underlying mechanism of action. In this study, 6-week-old male C57BL/6 mice were fed a high-fat diet (HFD) for 8 weeks to induce obesity, then continued on the HFD for another 8 weeks while orally administered GC. GC decreased ectopic fat accumulation in skeletal muscle and increased muscle weight, size, and function in obese mice. Furthermore, GC reduced skeletal muscle atrophy and increased hypertrophy in mice. We hypothesized that the activation of SIRT1/PGC1α by GC regulates skeletal muscle atrophy and hypertrophy. We observed that GC increased the expression of SIRT1 and PGC1α in skeletal muscle of mice and in C2C12 cells, which increased mitochondrial function and biogenesis. In addition, when C2C12 cells were treated with the SIRT1-specific inhibitor EX-527, no changes were observed in the protein levels of SIRT1 and PGC1α in the GC-treated C2C12 cells. Therefore, GC attenuated obesity-related muscle wasting by improving mitochondrial function and biogenesis through the activation of SIRT1/PGC1α in the skeletal muscle of mice.

Identification of phenolic compounds from fermented Moringa oleifera Lam. leaf supplemented with Fuzhuan brick tea and their volatile composition and anti-obesity activity

As a nutritious plant with valuable potential, the Moringa oleifera Lam. (MOL) leaf addition on Fuzhuan brick tea (FBT) for the co-fermentation (MOL-FBT) was an industry innovation and a new route to make full use of MOL leaf. After optimization of the extraction conditions, the best conditions for the polyphenols extraction method from MOL-FBT (MFP) were 60°C for 40 min (1:80, V/W) using response surface methodology. A total of 30 phenolics were identified and quantified. Most of the polyphenols were increased after adding MOL leaf for co-fermentation compared to FBT polyphenols. In particular, caffeic acids were found only in MFP. Moreover, the MFP received high value in taste, aroma, and color. In total, 62 volatile flavor compounds, consisting of 3 acids, 5 alcohols, 15 aldehydes, 4 esters, 20 hydrocarbons, 10 ketones, and 5 others, were identified in MFP. In addition, MFP inhibited 3T3-L1 preadipocyte differentiation in a dose-dependent manner and decreased lipid accumulation via the peroxisome proliferator-activated receptor gamma (PPARγ)/CCAAT/enhancer binding protein alpha (CEBPα)/cluster of differentiation 36 (CD36) axis and induced a brown adipocyte-like phenotype. In vivo experiments were further conducted to confirm the in vitro results. MFP regulated lipid accumulation, glucose/insulin tolerance, improved liver and kidney function, and inhibited the secretion of pro-inflammatory factors by the PPARγ/CEBPα/CD36 axis and alleviated inflammation in high fat and high fructose diet-induced obese mice. In summary, MFP possesses high-quality properties and anti-obesity effects, as well as the great potential to be used as a novel functional food product.

Smilax China L. polysaccharide prevents HFD induced-NAFLD by regulating hepatic fat metabolism and gut microbiota

BACKGROUND

The increasing incidence of nonalcoholic fatty liver disease (NAFLD) has urged the development of new therapeutics. NAFLD is intimately linked to gut microbiota due to the hepatic portal system, and utilizing natural polysaccharides as prebiotics has become a prospective strategy for preventing NAFLD. Smilax china L. polysaccharide (SCP) possesses excellent hepatoprotective and anti-inflammatory activity. However, its protective effects on NAFLD remains unclear.

PURPOSE

The goal of this study was to explore the protective effects of SCP on high-fat diet (HFD)-induced NAFLD mice by regulating hepatic fat metabolism and gut microbiota.

METHODS

Extraction and isolation from Smilax china L. rhizome to obtain SCP. C57BL/6 J mice were distributed to six groups: Control (normal chow diet), HFD-fed mice were assigned to HFD, simvastatin (SVT), and low-, medium-, high-doses of SCP for 12 weeks. The body, liver, and different adipose tissues weights were detected, and lipids in serum and liver were assessed. RT-PCR and Western blot were used to detect the hepatic fat metabolism-related genes and proteins. Gut microbiota of cecum contents was profiled through 16S rRNA gene sequencing.

RESULTS

SCP effectively reversed HFD-induced increase weights of body, liver, and different adipose tissues. Lipid levels of serum and liver were also significantly reduced after SCP intervention. According to the results of RT-PCR and western blot analysis, SCP treatment up-regulated the genes and proteins related to lipolysis were up-regulated, while lipogenesis-related genes and proteins were down-regulated. Furthermore, the HFD-induced dysbiosis of intestinal microbiota was similarly repaired by SCP intervention, including enriching beneficial bacteria and depleting harmful bacteria.

CONCLUSION

SCP could effectively prevent HFD-induced NAFLD, might be considered as a prebiotic agent due to its excellent effects on altering hepatic fat metabolism and maintaining gut microbiota homeostasis.

Fuzhuan brick tea extract ameliorates obesity-induced skeletal muscle atrophy by alleviating mitochondrial dysfunction in mice

Fuzhuan brick tea (FBT) is a post-fermented tea fermented by the fungus Eurotium cristatum and is mainly produced in Hunan Province, China. Our previous study revealed that FBT extract prevents obesity by increasing energy expenditure and mitochondrial content in mice. Therefore, in this study, we hypothesized that FBT extract could be effective in alleviating obesity-induced muscle atrophy by addressing mitochondrial dysfunction, and aimed to explore the underlying molecular mechanism of FBT extract in high-fat diet-induced obese mice. FBT extract increased skeletal muscle weight and size, myosin heavy chain isoforms, and muscle performance in obese mice. Additionally, FBT extract reduced obesity-induced intramuscular lipids, skeletal muscle inflammation, and the expression of skeletal muscle atrophy markers, and increased the expression of fibronectin type III domain-containing protein 5 in skeletal muscles. Obesity-induced skeletal muscle mitochondrial dysfunction was improved by FBT extract as analyzed through mitochondrial morphology, fatty acid oxidation, respiratory chain complexes, and mitochondrial dynamics and biogenesis. Epigallocatechin, a major bioactive compound in FBT extract, attenuated palmitic acid-induced muscle atrophy by regulating mitochondrial functions in C2C12 cells. In conclusion, FBT extract may prevent obesity-induced muscle atrophy by alleviating mitochondrial dysfunction in mice.

Fu Brick Tea as a Staple Food Supplement Attenuates High Fat Diet Induced Obesity in Mice

Fu brick tea (FBT), a product of microbial fermentation from primary dark tea, also known as raw material tea (RMT), has been extensively studied for its functional properties. However, its potential as a staple food supplement for weight loss remains poorly understood. This study compared the weight loss effects of orlistat, traditional plain noodles (NN), and noodles supplemented with varying amounts of RMT (RMTN) and FBT (FBTN), with the aim to elucidate their lipid-reducing effects and underlying mechanisms. Experimental trials on high fat diet fed mice revealed significant weight loss, lipid-lowering, and hypoglycemic effects upon supplementation with orlistat, RMTN, and FBTN. Moreover, supplementation with orlistat, RMTN, and FBTN effectively restored serum and liver-related index levels, mitigating high-fat diet-induced dyslipidemia. Additionally, these supplements ameliorated liver and kidney damage by inhibiting oxidative stress and inflammatory responses. Furthermore, orlistat, RMTN, and FBTN exert their anti-obesity effects primarily by modulating genes associated with lipid metabolism and inflammatory responses and through regulation of the composition and structure of the gut microbiota. Importantly, FBTN demonstrated a significantly stronger lipid-lowering effect compared to RMTN, particularly at higher tea addition ratios. In contrast, NN supplementation exhibited minimal to no weight loss effects. Based on these findings, it could be inferred that FBT holds promise as a staple food supplement to ameliorate high-fat diet-induced obesity and its associated health conditions.

Fuzhuan brick tea ameliorates hepatic steatosis and steatohepatitis through gut microbiota-derived aryl hydrocarbon receptor ligands in high-fat diet-induced obese mice

High-fat diet (HFD) induced obesity and its associated conditions, such as hepatic steatosis and steatohepatitis, are major health concerns worldwide. Previous studies have reported the excellent efficiency of Fuzhuan brick tea (FBT) in attenuating HFD-induced obesity and metabolic disorders. In this study, we investigated the effects of FBT on hepatic steatosis and simple steatohepatitis in HFD-induced obese mice, as well as the metabolic function of the gut microbiome using metagenomics and metabolomics. The results showed that FBT ameliorated dyslipidemia, hepatic steatosis and steatohepatitis in HFD-induced obese mice by normalizing the gut microbiota structure and tryptophan metabolism. FBT increased the cecal abundance of aryl hydrocarbon receptor (AhR)-ligand producing bacteria such as Lactobacillus_reuteri and Lactobacillus_johnsonii, at the expense of AhR-ligand consuming bacteria, such as Faecalibaculum_rodentium and Escherichia_coli, and elevated the cecal contents of AhR-ligands such as IAA, IPA, and KYNA. Furthermore, FBT regulated the expressions of AhR and its targeted lipometabolic genes such as Pemt, Fasn, and SREBP-1c, as well as other inflammatory genes including TNF-α, IL-6, and IL-1β in the liver of mice. Overall, these findings highlight the beneficial effects of FBT on obesity-related hepatic steatosis and steatohepatitis via microbiota-derived AhR signaling.

Characterization and quantification of chemical constituents in Fuzhuan brick tea using ultra-high-performance liquid chromatography-mass spectrometry

Fuzhuan brick tea, a distinctive dark tea fermented by microorganisms, is a traditional beverage in China throughout history. Recently, it has attracted considerable attention owing to its unique quality characteristics and potential health benefits. The aim of this study was to establish a method for the quality control of Fuzhuan brick tea for stable production. Ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry was used to identify Fuzhuan brick tea, and the major components were chosen for further quantitative analysis. Subsequently, a quantification method was developed using ultra-high-performance liquid chromatography coupled with triple-quadrupole mass spectrometry, and its reliability was verified through methodological validation. Finally, a total of 30 compounds were identified, including catechins, flavonoids, alkaloids, and fatty acids. The established method was reliable for methodological validation and was applied to the quantitative analysis of Fuzhuan brick tea. This study provides a fundamental basis for the quality control and further studies on the component analysis of Fuzhuan brick tea.

Characteristics of the microstructure and the key components of white kidney bean sourdough bread induced by mixed-strain fermentation and its influence on gut microbiota

In this study, the effect of mixed-strain fermentation using Kluyveromyces marxianus with either Lactobacillus plantarum or Pediococcus pentosaceus on the physiochemical and nutritional properties of white kidney bean flour sourdough was investigated. The results indicated that mixed-strain fermentation reduced the anti-nutritional factors produced from the white kidney bean flour, especially in the sourdough fermented by L. plantarum and K. marxianus (WKS-LK) compared to that by P. pentosaceus and K. marxianus (WKS-JK). Meanwhile, the content of lactic acid and acetic acid and the proportion of peptides with molecular weights ranging from <500 to 5000 Da were increased in the sourdoughs (WKS-LK > WKS-JK). Compared to the control (WK), microstructural characteristics of the dough seemed to be improved in WKS-LK followed by WKS-JK in terms of their corresponding gluten network consistency. Moreover, mixed fermentation led to a reduced starch digestibility accompanied by a higher content of resistant starch and slowly digestible starch. In contrast, protein digestibility was enhanced in WKS-LK and WKS-JK sourdough breads. More importantly, the changes in gut microbiota composition, short-chain fatty acid (SCFA) production, systemic inflammation, glucose tolerance and liver tissue histopathology following 21-day consumption of the sourdough bread were also evaluated via an animal model. The intake of sourdough breads reduced the abundance of the pathogenic microbiota Escherichia shigella. In contrast, the corresponding abundance of Rikenellaceae, Akkermansiaceae, Erysipelotrichaceae, Prevotellaceae and Eubacterium coprostanoligenes was increased, followed by enhanced SCFA generation, with the highest in WKS-LK and then WKS-JK. Meanwhile, a reduced level of pro-inflammatory cytokines IL-1β, IL-6 and TNF-α in the serum and improved glucose tolerance and liver tissue histopathology following the bread consumption were also achieved in the order of WKS-LK, then WKS-JK mice compared to WK.

Compound dark tea ameliorates obesity and hepatic steatosis and modulates the gut microbiota in mice

Dark tea is a fermented tea that plays a role in regulating the homeostasis of intestinal microorganisms. Previous studies have found that dark tea can improve obesity and has a lipid-lowering effect. In this study, green tea, Ilex latifolia Thunb (kuding tea) and Momordica grosvenori (Luo Han Guo) were added to a new compound dark tea (CDT), to improve the taste and health of this beverage. High-fat diet-fed C57BL/6J mice were treated with low- (6 mg/mL) or high- (12 mg/mL) concentrations of CDT for 18 weeks to assess their effect on lipid metabolism. Our results suggest that low- and high-concentrations of CDT could reduce body weight by 15 and 16% and by 44 and 38% of body fat, respectively, by attenuating body weight gain and fat accumulation, improving glucose tolerance, alleviating metabolic endotoxemia, and regulating the mRNA expression levels of lipid metabolism-related genes. In addition, low concentrations of CDT were able to reduce the abundance of Desulfovibrio, which is positively associated with obesity, and increase the abundance of Ruminococcus, which are negatively associated with obesity. This study demonstrates the effect of CDT on ameliorating lipid metabolism and provides new insights into the research and development of functional tea beverages.

Characterization of Hypolipidemic Phenol Analogues from Fermented Tea by Eurotium cristatum

Fuzhuan brick tea (FBT), a type of black tea, is a traditional beverage in China, especially popular among frontier ethnic groups. FBT is well-known for its health benefits, such as hypoglycemic, anti-hypertensive, anti-inflammatory, diuretic, and detoxification effects. Nevertheless, the underlying mechanisms on the molecular level are still elusive and the key compounds responsible for the health benefits are unidentified. Previous studies have mainly focused on functional studies of the water extract. However, FBT is typically cooked with butter or milk. Therefore, we hypothesized that some lipophilic components in FBT, which can be absorbed through the co-consumption of butter or milk, may play an important role in the health benefits. The present study aimed to investigate whether the liposoluble extract of FBT alleviates symptoms related to metabolic diseases and to identify the active compounds involved. By comparing the high-performance liquid chromatography (HPLC) profiles of water, milk and hexane extract, some low polarity peaks were observed in the milk and hexane extracts. Furthermore, the hexane extract treatment alleviated body weight gain, serum total cholesterol and triglyceride levels, and inhibited the accumulation of hepatic fat granules in a high-fat diet (HFD)-induced C57BL/6N mouse model. In order to identify the key functional lipophilic compounds in FBT, the hexane extract of FBT was subjected to chemical characterization. Four phenol analogs were characterized, namely, isodihydroauroglaucin (1), dihydroauroglaucin (2), tetrahydroauroglaucin (3), and flavoglaucin (4). Compounds 1 and 4 reduced the levels of total cholesterol and triglyceride in vivo. Both compounds also inhibited the high-fat diet-induced body weight gain and accumulation of fat granules in the liver of C57BL/6N mice. Isodihydroauroglaucin and flavoglaucin have therefore been identified as bioactive ingredients that contribute to the health benefits of FBT.

Cold-Brewed Jasmine Tea Attenuates High-Fat Diet-Induced Obesity and Gut Microbial Dysbiosis

Cold-brewed jasmine tea (CB-JT) is regarded to possess characteristic flavors and health benefits as a novel resource of functional tea beverages. To investigate the molecular mechanisms underlying CB-JT-mediated protective effects on obesity, we evaluated the serum biochemistry, histological condition, glucose tolerance, gene expression profile and intestinal microbial diversity in high-fat diet (HFD)-fed mice. Our results demonstrate that cold-brewed jasmine tea can significantly attenuate HFD-induced body weight gain, abnormal serum lipid levels, fat deposition, hepatic injury, inflammatory processes as well as metabolic endotoxemia. CB-JT also modified the microbial community composition in HFD-fed mice and altered the balance to one closely resembled that of the control group. The differential abundance of core microbes in obese mice was reversed by CB-JT treatment, including an increment in the abundance of Blautia, Mucispirillum, and Bilophila as well as a decrease in the abundance of Alloprevotella. CB-JT was proved to regulate the mRNA expression levels of lipid metabolism-related genes such as Leptin, Pgc1a Il6, and Il1b in the adipose tissue coupled with Cyp7a1, Lxra, Srebp1c, and Atgl in the liver. These findings indicate that cold-brewed jasmine tea might be served as a potential functional tea beverage to prevent obesity and gut microbiota dysbiosis.

Herbal Tea Essences (HTE) Ameliorate HFD-Induced Obesity

Tea is one of the most popular beverages in the world. The health-promoting effects of tea and its individual constituents, including antiobesity and antihyperlipidaemia effects, have been well accepted. In this study, we evaluated the effects of herbal tea essence (HTE), a commercial product extracted from black tea, on HFD-induced obesity in mice. HTE effectively reduces the gain in body weight and improves glucose tolerance and insulin sensitivity after HFD treatment. HTE inhibits lipid accumulation in the body and reduces serum lipid contents. Furthermore, HTE negatively regulates the expression levels of genes that control lipogenesis and gluconeogenesis and upregulates the expression of genes for lipid β oxidation. The regulatory effects of HTE on these genes may occur through activation of the AKT, IRS-1, and AMPK signalling pathways. Our observations suggest that HTE could be a promising option for nutritional intervention in the treatment of obesity.

The Complex of Phycobiliproteins, Fucoxanthin, and Krill Oil Ameliorates Obesity through Modulation of Lipid Metabolism and Antioxidants in Obese Rats

Phycobiliproteins, fucoxanthin, and krill oil are natural marine products with excellent activities. In the study, we prepared the complex of phycobiliproteins, fucoxanthin, and krill oil (PFK) and assessed the anti-obesity, lipid-lowering, and antioxidant activities in high-fat diet rats. The results showed that the rats significantly and safely reduced body weight gain and regulated serum biochemical parameters at 50 mg/kg phycobiliproteins, 10 mg/kg fucoxanthin, and 100 mg/kg krill oil. Furthermore, the molecular mechanism study suggested that the complex of PFK confined the enzyme activities of lipid synthesis and enhanced antioxidant activity to improve obesity indirectly. The conclusions demonstrated that the complex of PFK has potent anti-obesity and hypolipidemic effects which have potential use as a natural and healthy food and medicine for anti-obesity and lowering blood lipids in the future.

Gut Microbiota Differentially Mediated by Qingmao Tea and Qingzhuan Tea Alleviated High-Fat-Induced Obesity and Associated Metabolic Disorders: The Impact of Microbial Fermentation

Although dark tea is a unique microbial-fermented tea with a high reputation for having an antiobesity effect, little is known about the effect of microbial fermentation on tea leaves’ antiobesity properties. This study compared the antiobesity effects of microbial-fermented Qingzhuan tea (QZT) and unfermented Qingmao tea (QMT), providing insight into their underlying mechanisms associated with gut microbiota. Our results indicated that the supplementation of QMT extract (QMTe) and QZT extract (QZTe) displayed similar antiobesity effects in high-fat diet (HFD)-fed mice, but the hypolipidemic effect of QZTe was significantly stronger than that of QMTe. The microbiomic analysis indicated that QZTe was more effective than QMTe at regulating HFD-caused gut microbiota dysbiosis. Akkermansiaceae and Bifidobacteriaceae, which have negative correlations with obesity, were enhanced notably by QZTe, whereas Faecalibaculum and Erysipelotrichaceae, which are positively correlated with obesity, were decreased dramatically by QMTe and QZTe. A Tax4Fun analysis of QMTe/QZTe-mediated gut microbiota revealed that QMTe supplementation drastically reversed the HFD-induced upregulation of glycolysis and energy metabolism, whereas QZTe supplementation significantly restored the HFD-caused downregulation of pyruvate metabolism. Our findings suggested that microbial fermentation showed a limited effect on tea leaves’ antiobesity, but enhanced their hypolipidemic activity, and QZT could attenuate obesity and associated metabolic disorders by favorably modulating gut microbiota.

Inonotus hispidus Protects against Hyperlipidemia by Inhibiting Oxidative Stress and Inflammation through Nrf2/NF-κB Signaling in High Fat Diet Fed Mice

Obesity is frequently associated with dysregulated lipid metabolism and lipotoxicity. Inonotus hispidus (Bull.: Fr.) P. Karst (IH) is an edible and medicinal parasitic mushroom. In this study, after a systematic analysis of its nutritional ingredients, the regulatory effects of IH on lipid metabolism were investigated in mice fed a high-fat diet (HFD). In HFD-fed mice, IH reversed the pathological state of the liver and the three types of fat and significantly decreased the levels of low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), triglycerides (TG), and leptin (LEP) and increased the level of high-density liptein cholesterol (HDL-C) in serum. Meanwhile, IH ameliorated liver damage by reducing alanine aminotransferase (ALT), aspartate aminotransferase (AST), interleukin (IL)-1β, IL-6, tumor necrosis factor-alpha (TNF-α), and plasminogen activator inhibitor-1 (PAI-1) levels in the liver and serum. Compared with HFD-fed mice, IH significantly modulated the gut microbiota, changed the relative abundances of microflora at different taxonomic levels, and regulated lipid levels. The results showed that 30 differential lipids were found. Results from Western blotting confirmed that IH regulated the nuclear factor erythroid-2 related factor 2 (Nrf2)/nuclear factor-kappa B (NF-κB) signaling pathway and oxidative stress. This study aimed to provide experimental evidence for the applicability of IH in obesity treatment.

Modulation effects of microorganisms on tea in fermentation

Tea is a popular traditional drink and has been reported to exhibit various health-promoting effects because of its abundance of polyphenols. Among all the tea products, fermented tea accounts for the majority of tea consumption worldwide. Microbiota plays an important role in the fermentation of tea, which involves a series of reactions that modify the chemical constituents and thereby affect the flavor and bioactivities of tea. In the present review, the microorganisms involved in fermented tea and tea extracts in the recent studies were summarized and the modulation effects of microorganisms on tea in fermentation, including polyphenols composition and content, biological activities and sensory characteristics, were also critically reviewed. It is expected that the data summarized could provide some references for the development of microbial fermented tea drinks with specific nutrition and health benefits.

Naringenin activates beige adipocyte browning in high fat diet-fed C57BL/6 mice by shaping the gut microbiota

Naringenin activates beige adipose thermogenesis and browning by gut microbe-SCFAS-host interactions, which increases energy expenditure and prevents HFD induced obesity.