Corylin reduces obesity and insulin resistance and promotes adipose tissue browning through SIRT-1 and β3-AR activation

Adipose ZFP36 protects against diet-induced obesity and insulin resistance

AIMS

Obesity, as a worldwide healthcare problem, has become more prevalent. ZFP36 is a well-known RNA-binding protein and involved in the posttranscriptional regulation of many physiological processes. Whether the adipose ZFP36 plays a role in obesity and insulin resistance remains unclear.

METHODS

The expression levels of ZFP36 were analyzed in adipose tissues of obese patients, diet-induced obese mice, ob/ob mice and db/db mice. To determine whether adipose ZFP36 protects against the diet-induced obesity, we generated adipose-specific ZFP36 knockout (ZFP36AKO) mice, which were subjected to high-fat-diet (HFD) for 16 weeks. To explore the specific molecular mechanisms of ZFP36 regulating metabolic disorders, we used gene array assay of control and ZFP36-deficient adipose tissue, and assessed the pathways in vitro and vivo.

RESULTS

Western blotting and RT-PCR were performed to determine the downregulating level of ZFP36 in adipose tissues of obese patients, diet-induced obese mice, ob/ob mice and db/db mice. Relative to control mice, ZFP36AKO mice were more susceptible to HFD-induced obesity, along with insulin resistance, glucose tolerance, and increased metabolic disorders. The obesity of ZFP36AKO mice was attributed to hypertrophy of adipocytes in white adipose tissue via decreased expression of Perilipin1 (PLIN1), adipose triglyceride lipase (ATGL), and hormone-sensitive lipase (HSL). We discovered that ZFP36 oppositely regulated RNF128 expression by repressing the mRNA stability and translation of RNF128, a negative regulator of Sirt1 expression.

CONCLUSIONS

This study suggests that ZFP36 in adipose tissue plays an important role in diet-induced obesity, and identifies a novel molecular signaling pathway of ZFP36/RNF128/Sirt1 involved in obesity.

Chitooligosaccharide-epigallocatechin gallate conjugate ameliorates lipid accumulation and promotes browning of white adipose tissue in high fat diet fed rats

The prevalence of obesity has increased progressively worldwide. Obesity is characterized by excessive accumulation of fat in adipose tissues, leading to metabolic impairment. The anti-obese effects of chitooligosaccharide (COS) and epigallocatechin-3-gallate (EGCG) have been extensively clarified. This study aimed to investigate the effects and potential mechanisms of the COS-EGCG conjugate (CE) on anti-obesity, specifically by alleviating lipid accumulation and promoting the browning of white adipose tissue (WAT) in obese rats. Obesity as a consequence of a high-fat diet (HFD) was induced in male Wistar rats. The HFD was given for 16 weeks and the rats were then randomly subdivided into five groups namely: vehicle (control group), HFD plus CE at 150 mg/kg/day, HFD plus CE at 600 mg/kg/day, HFD plus COS at 600 mg/kg/day, and HFD plus atorvastatin at 10 mg/kg/day for 4 weeks. CE could reduce body weight, improve serum lipid profiles, and promote lipid metabolism via activation of AMP-activated protein kinase (AMPK) in WAT and enhance the processes of WAT browning by activating sirtuin 1 (Sirt 1), peroxisome proliferator-activated receptor-gamma coactivator (PGC1-α), and uncoupling the protein 1 (UCP1) signaling pathway. CE reduced obesity and promoted WAT browning in HFD-fed rats. Therefore, CE might be a new therapy for metabolic syndrome and obesity.

Advances in inflammatory senescence in liver disease

Inflammatory senescence is a process of cellular dysfunction associated with chronic inflammation, which plays a significant role in the onset and progression of liver diseases,and the research on its mechanisms becomes a hotspot currently. In viral hepatitis, the mechanisms of inflammatory senescence primarily involve oxidative stress, cell apoptosis and necrosis, as well as gut microbiota dysbiosis. In non-alcoholic fatty liver disease, the mechanisms of inflammatory senescence are more complex, involving insulin resistance, fat deposition, lipid metabolism disorders, gut microbiota dysbiosis, and NAD+ metabolism abnormalities. In liver tumors, inflammatory senescence is characterized by the weakening of tumor suppressive mechanisms, remodeling of the liver microenvironment, metabolic reprogramming, and enhanced immune evasion. Therapeutic strategies targeting inflammatory senescence have been developing recently, and antioxidant therapy, metabolic disorder improvement, and immunotherapy emerging are important interventions for liver diseases. This review focuses on the mechanisms of inflammatory secescence in liver diseases, aiming to provide novel insights for the prevention and treatment of liver diseases.

Role of sirtuins in obesity and osteoporosis: molecular mechanisms and therapeutic targets

The prevalence of obesity and osteoporosis (OP) represents a significant public health concern on a global scale. A substantial body of evidence indicates that there is a complex relationship between obesity and OP, with a correlation between the occurrence of OP and obesity. In recent years, sirtuins have emerged as a prominent area of interest in the fields of aging and endocrine metabolism. Among the various research avenues exploring the potential of sirtuins, the effects of these proteins on obesity and OP have garnered significant attention from numerous researchers. Sirtuins regulate energy balance and lipid balance, which in turn inhibit the process of adipogenesis. Additionally, sirtuins regulate the balance between osteogenic and osteoblastic activity, which protects against the development of OP. However, no study has yet provided a comprehensive discussion of the relationship between the three: sirtuins, obesity, and OP. This paper will therefore describe the relationship between sirtuins and obesity, the relationship between sirtuins and OP, and a discussion focusing on the possibility of treating OP caused by obesity by targeting sirtuins. This will be based on the common influences on the occurrence of obesity and OP (such as mesenchymal stem cells, gut microbiota, and insulin). Finally, the potential of SIRT1, an important member of sirtuins, in polyphenolic natural products for the treatment of obesity and OP will be presented. This will contribute to a better understanding of the interactions between sirtuins and obesity and bone, which will facilitate the development of new therapeutic strategies for obesity and OP in the future.

Flavonoids for gastrointestinal tract local and associated systemic effects: A review of clinical trials and future perspectives

BACKGROUND

Flavonoids are naturally occurring dietary phytochemicals with significant antioxidant effects aside from several health benefits. People often consume them in combination with other food components. Compiling data establishes a link between bioactive flavonoids and prevention of several diseases in animal models, including cardiovascular diseases, diabetes, gut dysbiosis, and metabolic dysfunction-associated steatotic liver disease (MASLD). However, numerous clinical studies have demonstrated the ineffectiveness of flavonoids contradicting rodent models, thereby challenging the validity of using flavonoids as dietary supplements.

AIM OF REVIEW

This review provides a clinical perspective to emphasize the effective roles of dietary flavonoids as well as to summarize their specific mechanisms in animals briefly.

KEY SCIENTIFIC CONCEPTS OF REVIEW

First, this review offers an in-depth elucidation of the metabolic processes of flavonoids within human, encompassing the small, large intestine, and the liver. Furthermore, the review provides a comprehensive overview of the various functions of flavonoids in the gastrointestinal tract, including hindering the breakdown and assimilation of macronutrients, such as polysaccharides and lipids, regulating gut hormone secretion as well as inhibition of mineral iron absorption. In the large intestine, an unabsorbed major portion of flavonoids interact with the gut flora leading to their biotransformation. Once absorbed and circulated in the bloodstream, bioactive flavonoids or their metabolites exert numerous beneficial systemic effects. Lastly, we examine the protective effects of flavonoids in several metabolic disorders, including endothelial dysfunction, MASLD, cardiovascular disease, obesity, hyperlipidemia, and insulin resistance. In conclusion, this review outlines the safety and future prospects of flavonoids in the field of health, especially in the prevention of metabolic syndrome (MetS).

Bone Adaptations to a Whole Body Vibration Protocol in Murine Models of Different Ages: A Preliminary Study on Structural Changes and Biomarker Evaluation

Background/Objectives: Whole body vibration (WBV) is a valuable tool to mitigate physiological adaptations related to age and inactivity. Although significant benefits have been found at the musculoskeletal level, including increased bone mass and reduced muscle atrophy, the underlying biological mechanisms remain largely unknown. Therefore, our study aimed to evaluate the effects of vibratory training on bone tissue in murine models of different age groups by investigating the structural and distribution changes in some crucial biomarkers involved in musculoskeletal homeostasis. Methods: Specifically, 4-, 12-, and 24-month-old mice were trained with a WBV protocol characterized by three series of 2 min and 30 s, interspersed with a recovery period of the same duration, on a 3-weekly frequency for 3 months. At the end of the training, histological and morphometric analyses were conducted, in association with immunohistochemical analysis to investigate changes in the distribution of fibronectin type III domain-containing protein 5 (FNDC5), NADPH oxidase 4 (NOX4), and sirtuin 1 (SIRT1). Results: Our preliminary results showed that WBV improves musculoskeletal health by preserving bone architecture and promoting up-regulation of FNDC5 and SIRT1 and down-regulation of NOX4. Conclusions: Our study confirms vibratory training as a viable alternative to counter musculoskeletal decline in elderly and/or sedentary subjects. Further investigations should be conducted to deepen knowledge in this field and explore the role of other molecular mediators in physiological adaptations to vibration.

The β3-Adrenergic Receptor: Structure, Physiopathology of Disease, and Emerging Therapeutic Potential

The discovery and characterization of the signal cascades of the β-adrenergic receptors have made it possible to effectively target the receptors for drug development. β-Adrenergic receptors are a class A rhodopsin type of G protein-coupled receptors (GPCRs) that are stimulated mainly by catecholamines and therefore mediate diverse effects of the parasympathetic nervous system in eliciting "fight or flight" type responses. They are detectable in several human tissues where they control a plethora of physiological processes and therefore contribute to the pathogenesis of several disease conditions. Given the relevance of the β-adrenergic receptor as a molecular target for many pathological conditions, this comprehensive review aims at providing an in-depth exploration of the recent advancements in β3-adrenergic receptor research. More importantly, we delve into the prospects of the β3-adrenergic receptor as a therapeutic target across a variety of clinical domains.

HPLC/ESI-QTOF-MS/MS based untargeted metabolomics authentication of Taxus × media six tissues

INTRODUCTION

Taxus media (Taxus × media Rehder) is renowned for its high paclitaxel content, serving as a major source for industrial paclitaxel production. In addition to paclitaxel, T. media contains a diverse range of metabolites, including flavonoids, alkaloids, and terpenoids, which have been shown to possess antioxidant, antibacterial, anti-inflammatory, and immunomodulatory effects. However, these compounds have not been thoroughly studied as key metabolites in T. media.

OBJECTIVE

The untargeted metabolomics analysis of six T. media tissues provides new insights into the development and utilization of T. media metabolites.

METHOD

The extracts from six tissues of T. media were analyzed and subjected to analysis using high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS/MS) and chemometric techniques.

RESULTS

Using a reliable HPLC-Q-TOF-MS/MS method, we identified 312 compounds in six T. media tissues, including 214 previously unreported in T. media. To identify characteristic compounds across different tissues, 34 metabolites were further screened. KEGG metabolic pathway analysis revealed that these compounds primarily occur in the metabolic pathways of terpene glycosides, flavans, and O-methylated flavonoids.

CONCLUSION

This study initially utilized an HPLC-QTOF-MS/MS-based metabolomics approach to assess the metabolites in different tissues of T. media, providing a basis for their utilization and management.

Ling-gui-zhu-gan promotes adipocytes browning via targeting the miR-27b/PRDM16 pathway in 3T3-L1 cells

Introduction: Obesity, a global epidemic, is caused by an imbalance between energy intake and expenditure. The induction of white adipose browning to increase heat production has emerged as a potential effective strategy to address obesity. Ling-gui-zhu-gan (LGZG), a traditional Chinese medicine formula, has been proved to achieve promising results to combat obesity and related metabolic diseases, yet the mechanisms remain largely unexplored. This study aimed to elucidate the anti-obesity properties and the mechanisms of LGZG by investigating its browning effect on 3T3-L1 adipocytes. Methods: LGZG-containing serum obtained by oral administration of LGZG to animals was added to 3T3-L1 adipocytes to simulate in vivo conditions. Results: The results showed that 49 compounds were identified in LGZG-containing serum by UHPLC-Q-Orbitrap HRMS, including compounds such as atractylenolides and polyporenic acid C, etc. LGZG-containing serum alleviated the lipid accumulation and decreased both intracellular and extracellular triglyceride contents in a dose-dependent manner. This reduction is accompanied by enhanced mitochondrial respiratory and heat production function. Mechanistically, LGZG-containing serum led to a decrease in miR-27b expression and an increase in the mRNA and protein levels of browning-related markers, including UCP1, PRDM16, PGC-1α, PPARγ, CTBP1, and CTBP2. Further investigation using miR-27b mimic transfection confirmed that miR-27b/PRDM16 pathway might be a potential mechanism by which LGZG-containing serum promotes browning of 3T3-L1 adipocytes. Discussion: These results underscore the therapeutic potential of LGZG in addressing obesity and its associated metabolic disorders through the promotion of adipose browning.

Ling-gui-zhu-gan granules reduces obesity and ameliorates metabolic disorders by inducing white adipose tissue browning in obese mice

Background

Ling-gui-zhu-gan (LGZG) formula has been demonstrated to effectively ameliorate the clinical symptoms of patients with obesity or metabolic syndrome. This study aimed to explore both the effect and the underlying mechanisms of LGZG against obesity.

Methods

Male C57BL/6N mice were randomized into four groups (n = 8): normal control (NC), obese (OB), metformin (Met), and LGZG. After 8 weeks of gavage administration, the pharmacological effects of LGZG on obesity and metabolism were investigated using biochemical parameters, histomorphological examination, and lipidomics techniques. Pivotal factors associated with white adipose tissue browning were evaluated using quantitative real-time polymerase chain reaction and western blotting.

Results

The results revealed that LGZG reduced the levels of obesity markers, including body weights, body fat mass and food intake in obese mice. Further evaluations highlighted that LGZG restored glucose homeostasis and significantly improved insulin sensitivity in obese mice. Importantly, LGZG could adjust serum lipid profiles and regulate the lipidomic spectrum of intestinal contents, with noticeable shifts in the levels of certain lipids, particularly diacylglycerols and monoacylglycerols. Histopathological examinations of LGZG-treated mice also revealed more favorable adipose tissue structures than their obese counterparts. Furthermore, we found that LGZG upregulated the expression of several key thermogenesis-related factors, such as UCP1, PRDM16, PGC-1α, PPARα, PPARγ, CTBP1, and CTBP2 in white adipose tissues.

Conclusion

Our findings position LGZG as a novel strategy for preventing obesity and improving metabolic health.

Increasing DNA damage sensitivity through corylin-mediated inhibition of homologous recombination

BACKGROUND

DNA repair allows the survival of cancer cells. Therefore, the development of DNA repair inhibitors is a critical need for sensitizing cancers to chemoradiation. Sae2CtIP has specific functions in initiating DNA end resection, as well as coordinating cell cycle checkpoints, and it also greatly interacts with the DDR at different levels.

RESULTS

In this study, we demonstrated that corylin, a potential sensitizer, causes deficiencies in DNA repair and DNA damage checkpoints in yeast cells. More specifically, corylin increases DNA damage sensitivity through the Sae2-dependent pathway and impairs the activation of Mec1-Ddc2, Rad53-p and γ-H2A. In breast cancer cells, corylin increases apoptosis and reduces proliferation following Dox treatment by inhibiting CtIP. Xenograft assays showed that treatment with corylin combined with Dox significantly reduced tumor growth in vivo.

CONCLUSIONS

Our findings herein delineate the mechanisms of action of corylin in regulating DNA repair and indicate that corylin has potential long-term clinical utility as a DDR inhibitor.

Molecular Regulation of Thermogenic Mechanisms in Beige Adipocytes

Adipose tissue is conventionally recognized as a metabolic organ responsible for storing energy. However, a proportion of adipose tissue also functions as a thermogenic organ, contributing to the inhibition of weight gain and prevention of metabolic diseases. In recent years, there has been significant progress in the study of thermogenic fats, particularly brown adipose tissue (BAT). Despite this progress, the mechanism underlying thermogenesis in beige adipose tissue remains highly controversial. It is widely acknowledged that beige adipose tissue has three additional thermogenic mechanisms in addition to the conventional UCP1-dependent thermogenesis: Ca2+ cycling thermogenesis, creatine substrate cycling thermogenesis, and triacylglycerol/fatty acid cycling thermogenesis. This paper delves into these three mechanisms and reviews the latest advancements in the molecular regulation of thermogenesis from the molecular genetic perspective. The objective of this review is to provide readers with a foundation of knowledge regarding the beige fats and a foundation for future research into the mechanisms of this process, which may lead to the development of new strategies for maintaining human health.

Flavonoids, gut microbiota, and host lipid metabolism

Flavonoids are widely distributed in nature and have a variety of beneficial biological effects, including antioxidant, anti-inflammatory, and anti-obesity effects. All of these are related to gut microbiota, and flavonoids also serve as a bridge between the host and gut microbiota. Flavonoids are commonly used to modify the composition of the gut microbiota by promoting or inhibiting specific microbial species within the gut, as well as modifying their metabolites. In turn, the gut microbiota extensively metabolizes flavonoids. Hence, this reciprocal relationship between flavonoids and the gut microbiota may play a crucial role in maintaining the balance and functionality of the metabolism system. In this review, we mainly highlighted the biological effects of antioxidant, anti-inflammatory and antiobesity, and discussed the interaction between flavonoids, gut microbiota and lipid metabolism, and elaborated the potential mechanisms on host lipid metabolism.

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.

Unveiling the Potential of Natural Compounds: A Comprehensive Review on Adipose Thermogenesis Modulation

The process of adipocyte browning has recently emerged as a novel therapeutic target for combating obesity and obesity-related diseases. Non-shivering thermogenesis is the process of biological heat production in mammals and is primarily mediated via brown adipose tissue (BAT). The recruitment and activation of BAT can be induced through chemical drugs and nutrients, with subsequent beneficial health effects through the utilization of carbohydrates and fats to generate heat to maintain body temperature. However, since potent drugs may show adverse side effects, nutritional or natural substances could be safe and effective as potential adipocyte browning agents. This review aims to provide an extensive overview of the natural food compounds that have been shown to activate brown adipocytes in humans, animals, and in cultured cells. In addition, some key genetic and molecular targets and the mechanisms of action of these natural compounds reported to have therapeutic potential to combat obesity are discussed.

Potential Role of Pig UCP3 in Modulating Adipocyte Browning via the Beta-Adrenergic Receptor Signaling Pathway

Adipose tissue plays an important role in regulating body temperature and metabolism, with white adipocytes serving as storage units for energy. Recent research focused on the browning of white adipocytes (beige adipocytes), causing thermogenesis and lipolysis. The process of browning is linked to the activation of uncoupling protein (UCP) expression, which can be mediated by the β3 adrenergic receptor pathway. Transcriptional factors, such as peroxisome proliferator activated receptor γ (PPARγ) and PPARγ coactivator 1 alpha, play vital roles in cell fate determination for fat cells. Beige adipocytes have metabolic therapeutic potential to combat diseases such as obesity, diabetes mellitus, and dyslipidemia, owing to their significant impact on metabolic functions. However, the molecular mechanisms that cause the induction of browning are unclear. Therefore, research using animal models and primary culture is essential to provide an understanding of browning for further application in human metabolic studies. Pigs have physiological similarities to humans; hence, they are valuable models for research on adipose tissue. This study demonstrates the browning potential of pig white adipocytes through primary culture experiments. The results show that upregulation of UCP3 gene expression and fragmentation of lipid droplets into smaller particles occur due to isoproterenol stimulation, which activates beta-adrenergic receptor signaling. Furthermore, PPARγ and PGC-1α were found to activate the UCP3 promoter region, similar to that of UCP1. These findings suggest that pigs undergo metabolic changes that induce browning in white adipocytes, providing a promising approach for metabolic research with potential implications for human health. This study offers valuable insights into the mechanism of adipocyte browning using pig primary culture that can enhance our understanding of human metabolism, leading to cures for commonly occurring diseases.

Olodaterol promotes thermogenesis in brown adipocytes via regulation of the β2-AR/cAMP/PKA signaling pathway

The escalating incidence of metabolic pathologies such as obesity and diabetes mellitus underscores the imperative for innovative therapeutics targeting lipid metabolism modulation. Within this context, augmenting thermogenic processes in adipose cells emerges as a viable therapeutic approach. Given the limitations of previous β3-adrenergic receptor (β3-AR) agonist treatments in human diseases, there is an increasing focus on therapies targeting the β2-adrenergic receptor (β2-AR). Olodaterol (OLO) is a potent β2-AR agonist that is a potential novel pharmacological candidate in this area. Our study explores the role and underlying mechanisms of OLO in enhancing brown adipose thermogenesis, providing robust evidence from in vitro and in vivo studies. OLO demonstrated a dose-dependent enhancement of lipolysis, notably increasing the expression of Uncoupling Protein 1 (UCP1) and raising the rate of oxygen consumption in primary brown adipocytes. This suggests a significant increase in thermogenic potential and energy expenditure. The administration of OLO to murine models noticeably enhanced cold-induced nonshivering thermogenesis. OLO elevated UCP1 expression in the brown adipose tissue of mice. Furthermore, it promoted brown adipocyte thermogenesis by activating the β2-AR/cAMP/PKA signaling cascades according to RNA sequencing, western blotting, and molecular docking analysis. This investigation underscores the therapeutic potential of OLO for metabolic ailments and sheds light on the intricate molecular dynamics of adipocyte thermogenesis, laying the groundwork for future targeted therapeutic interventions in human metabolic disorders.

Inhibitory effects of naringenin on estrogen deficiency-induced obesity via regulation of mitochondrial dynamics and AMPK activation associated with white adipose tissue browning

AIMS

Post-ovariectomy (OVX) changes in hormones induce obesity and white adipose tissue (WAT) inflammation. Increased energy expenditure via WAT browning is a novel therapeutic strategy for treating obesity. Naringenin (NAR) reduces inflammation and lipogenesis in obesity and attenuates estrogen deficiency-associated metabolic disorders; however, its role in WAT browning remains unclear.

MATERIALS AND METHODS

We investigated NAR ability to inhibit estrogen deficiency-associated obesity in vivo using a rat model and in vitro using 3T3-L1 adipocytes.

KEY FINDINGS

NAR significantly decreased the body weight and WAT mass of rats. O2 consumption, CO2 production, and energy expenditure were significantly lower in the OVX group than in the sham group, but NAR treatment reversed these effects of OVX. NAR treatment markedly improved glucose intolerance and lipid profiles as well as leptin, adiponectin, and irisin levels. NAR upregulated markers of browning and mitochondrial biogenesis in inguinal WAT. Moreover, it enhanced markers of mitochondrial fusion and inhibited fission via activating the AMP-activated protein kinase pathway. Similar results were observed in 3T3-L1 adipocytes. Moreover, NAR-induced mitochondrial biogenesis and fusion were suppressed by dorsomorphin (an AMP-activated protein kinase inhibitor).

SIGNIFICANCE

NAR alleviates obesity and metabolic dysfunction through the induction of WAT browning achieved via the modulation of AMP-activated protein kinase-regulated mitochondrial dynamics in WATs. NAR supplementation may therefore represent a potential intervention for preventing postmenopausal adipose tissue dysregulation.

Epigenetics in obesity: Mechanisms and advances in therapies based on natural products

Obesity is a major risk factor for morbidity and mortality because it has a close relationship to metabolic illnesses, such as diabetes, cardiovascular diseases, and some types of cancer. With no drugs available, the mainstay of obesity management remains lifestyle changes with exercise and dietary modifications. In light of the tremendous disease burden and unmet therapeutics, fresh perspectives on pathophysiology and drug discovery are needed. The development of epigenetics provides a compelling justification for how environmental, lifestyle, and other risk factors contribute to the pathogenesis of obesity. Furthermore, epigenetic dysregulations can be restored, and it has been reported that certain natural products obtained from plants, such as tea polyphenols, ellagic acid, urolithins, curcumin, genistein, isothiocyanates, and citrus isoflavonoids, were shown to inhibit weight gain. These substances have great antioxidant potential and are of great interest because they can also modify epigenetic mechanisms. Therefore, understanding epigenetic modifications to target the primary cause of obesity and the epigenetic mechanisms of anti-obesity effects with certain phytochemicals can prove rational strategies to prevent the disease and develop novel therapeutic interventions. Thus, the current review aimed to summarize the epigenetic mechanisms and advances in therapies for obesity based on natural products to provide evidence for the development of several potential anti-obesity drug targets.

Deletion of the mitochondrial calcium uniporter in adipose tissue promotes energy expenditure and alleviates diet-induced obesity

OBJECTIVE

Studies have shown a correlation between obesity and mitochondrial calcium homeostasis, yet it is unclear whether and how Mcu regulates adipocyte lipid deposition. This study aims to provide new potential target for the treatment of obesity and related metabolic diseases, and to explore the function of Mcu in adipose tissue.

METHODS

We firstly investigated the role of mitoxantrone, an Mcu inhibitor, in the regulation of glucose and lipid metabolism in mouse adipocytes (3T3-L1 cells). Secondly, C57BL/6J mice were used as a research model to investigate the effects of Mcu inhibitors on fat accumulation and glucose metabolism in mice on a high-fat diet (HFD), and by using CRISPR/Cas9 technology, adipose tissue-specific Mcu knockdown mice (Mcufl/+ AKO) and Mcu knockout of mice (Mcufl/fl AKO) were obtained, to further investigate the direct effects of Mcu on fat deposition, glucose tolerance and insulin sensitivity in mice on a high-fat diet.

RESULTS

We found the Mcu inhibitor reduced adipocytes lipid accumulation and adipose tissues mass in mice fed an HFD. Both Mcufl/+ AKO mice and Mcufl/fl AKO mice were resistant to HFD-induced obesity, compared to control mice. Mice with Mcufl/fl AKO showed improved glucose tolerance and insulin sensitivity as well as reduced hepatic lipid accumulation. Mechanistically, inhibition of Mcu promoted mitochondrial biogenesis and adipocyte browning, increase energy expenditure and alleviates diet-induced obesity.

CONCLUSIONS

Our study demonstrates a link between adipocyte lipid accumulation and mCa2+ levels, suggesting that adipose-specific Mcu deficiency alleviates HFD-induced obesity and ameliorates metabolic disorders such as insulin resistance and hepatic steatosis. These effects may be achieved by increasing mitochondrial biosynthesis, promoting white fat browning and enhancing energy metabolism.

Natural compounds as obesity pharmacotherapies

Obesity has become a serious global public health problem, affecting over 988 million people worldwide. Nevertheless, current pharmacotherapies have proven inadequate. Natural compounds have garnered significant attention due to their potential antiobesity effects. Over the past three decades, ca. 50 natural compounds have been evaluated for the preventive and/or therapeutic effects on obesity in animals and humans. However, variations in the antiobesity efficacies among these natural compounds have been substantial, owing to differences in experimental designs, including variations in animal models, dosages, treatment durations, and administration methods. The feasibility of employing these natural compounds as pharmacotherapies for obesity remained uncertain. In this review, we systematically summarized the antiobesity efficacy and mechanisms of action of each natural compound in animal models. This comprehensive review furnishes valuable insights for the development of antiobesity medications based on natural compounds.

Mitigation of BMP-induced inflammation in craniofacial bone regeneration and improvement of bone parameters by dietary hesperidin

Based on anti-inflammatory and osteogenic properties of hesperidin (HE), we hypothesized its systemic administration could be a cost-effective method of improving BMP-induced bone regeneration. Sprague-Dawley rats were allocated into 4 groups (n = 10/group): a 5-mm critical-sized mandible defect + collagen scaffold or, scaffold + 1 µg of BMP2 with and without dietary HE at 100 mg/kg. HE was administered by oral gavage 4 weeks prior to surgeries until euthanasia at day 7 or 14 post-surgery. The healing tissue within the defect collected at day 7 was subjected to gene expression analysis. Mandibles harvested at day 14 were subjected to microcomputed tomography and histology. HE + BMP2-treated rats had a statistically significant decrease in expression of inflammatory genes compared to BMP2 alone. The high-dose BMP2 alone caused cystic-like regeneration with incomplete defect closure. HE + BMP2 showed virtually complete bone fusion. Collagen fibril birefringence pattern (red color) under polarized light indicated high organization in BMP2-induced newly formed bone (NFB) in HE-supplemented group (p < 0.05). Clear changes in osteocyte lacunae as well as a statistically significant increase in osteoclasts were found around NFB in HE-treated rats. A significant increase in trabecular volume and thickness, and trabecular and cortical density was found in femurs of HE-supplemented rats (p < 0.05). Our findings show, for the first time, that dietary HE has a remarkable modulatory role in the function of locally delivered high-dose BMP2 in bone regeneration possibly via control of inflammation, osteogenesis, changes in osteocyte and osteoclast function and collagen maturation in regenerated and native bone. In conclusion, HE had a significant skeletal bone sparing effect and the ability to provide a more effective BMP-induced craniofacial regeneration.

From genes to systems: The role of food supplementation in the regulation of sepsis-induced inflammation

Systemic inflammation includes a widespread immune response to a harmful stimulus that results in extensive systemic damage. One common example of systemic inflammation is sepsis, which is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Under the pro-inflammatory environment of sepsis, oxidative stress contributes to tissue damage due to dysfunctional microcirculation that progressively causes the failure of multiple organs that ultimately triggers death. To address the underlying inflammatory condition in critically ill patients, progress has been made to assess the beneficial effects of dietary supplements, which include polyphenols, amino acids, fatty acids, vitamins, and minerals that are recognized for their immuno-modulating, anticoagulating, and analgesic properties. Therefore, we aimed to review and discuss the contribution of food-derived supplementation in the regulation of inflammation from gene expression to physiological responses and summarize the precedented potential of current therapeutic approaches during systemic inflammation.

Lipopolysaccharide-induced persistent inflammation ameliorates fat accumulation by promoting adipose browning in vitro and in vivo

This work aimed to explore whether the persistent inflammation induced by lipopolysaccharide (LPS) ameliorates fat accumulation by promoting adipose browning in vitro and in vivo. LPS over 1 ng/mL reduced lipid accumulation while increasing the expressions of specific genes involved in inflammation, mitochondrial biogenesis, and adipose browning in 3T3-L1 adipocytes. Moreover, LPS in intraperitoneal injection decreased white adipose tissue weight and elevated interscapular brown adipose tissue weight in mice. According to RT-PCR and western blot analysis results, the expressions of genes and proteins related to inflammation, mitochondrial biogenesis, lipolysis, and brown or beige markers in different tissues were elevated after LPS intervention. Cumulatively, LPS-induced persistent inflammation may potentially ameliorate fat accumulation by facilitating adipose browning in 3T3-L1 adipocytes and mice. These results offer new perspectives into the effect of persistent inflammation induced by LPS on regulating fat metabolism, thereby reducing fat accumulation by boosting adipose browning procedure.

Mulberry leaf flavonoids activate BAT and induce browning of WAT to improve type 2 diabetes via regulating the AMPK/SIRT1/PGC-1α signaling pathway

Mulberry (Morus alba L.) leaf is a well-established traditional Chinese botanical and culinary resource. It has found widespread application in the management of diabetes. The bioactive constituents of mulberry leaf, specifically mulberry leaf flavonoids (MLFs), exhibit pronounced potential in the amelioration of type 2 diabetes (T2D). This potential is attributed to their ability to safeguard pancreatic β cells, enhance insulin resistance, and inhibit α-glucosidase activity. Our antecedent research findings underscore the substantial therapeutic efficacy of MLFs in treating T2D. However, the precise mechanistic underpinnings of MLF's anti-T2D effects remain the subject of inquiry. Activation of brown/beige adipocytes is a novel and promising strategy for T2D treatment. In the present study, our primary objective was to elucidate the impact of MLFs on adipose tissue browning in db/db mice and 3T3-L1 cells and elucidate its underlying mechanism. The results manifested that MLFs reduced body weight and food intake, alleviated hepatic steatosis, improved insulin sensitivity, and increased lipolysis and thermogenesis in db/db mice. Moreover, MLFs activated brown adipose tissue (BAT) and induced the browning of inguinal white adipose tissue (IWAT) and 3T3-L1 adipocytes by increasing the expressions of brown adipocyte marker genes and proteins such as uncoupling protein 1 (UCP1) and beige adipocyte marker genes such as transmembrane protein 26 (Tmem26), thereby promoting mitochondrial biogenesis. Mechanistically, MLFs facilitated the activation of BAT and the induction of WAT browning to ameliorate T2D primarily through the activation of AMP-activated protein kinase (AMPK)/sirtuin 1 (SIRT1)/peroxisome proliferator-activated receptor-gamma coactivator 1α (PGC-1α) signaling pathway. These findings highlight the unique capacity of MLF to counteract T2D by enhancing BAT activation and inducing browning of IWAT, thereby ameliorating glucose and lipid metabolism disorders. As such, MLFs emerge as a prospective and innovative browning agent for the treatment of T2D.

Native-compound-Coupled Affinity Matrix (NCAM) in target identification and validation of bioactive compounds: Application, mechanism and outlooks

In drug discovery and development, the direct target identification of bioactive small molecules plays a significant role for understanding the mechanism of action, predicting the side effects, and rationally designing more potent compounds. However, due to the complicated regulatory processes in a cell together with thousands of biomacromolecules, target identification is always the major obstacle. New methods and technologies are continuously invented to tackle this problem. Nevertheless, the mainly used tools possess several disadvantages. High synthetic skills are typically required to laboriously synthesize a probe for protein enrichment. To detect the ligand-protein interaction by analyzing proteins' responses to proteolytic or thermal treatment, costly and precise instruments are always necessary. Therefore, convenient and practical techniques are urgently needed. Over the past decades, a strategy using native compounds without the requirement of chemical modification, also termed Native-compound-Coupled Affinity Matrix (NCAM), is developing continuously. Two practical tactics based on "label-free" compounds have been invented and used, that is Photo-cross-linked Small-molecule Affinity Matrix (PSAM) and Native-compound-Coupled CNBr-activated Beads (NCCB). Presently, we will elucidate the characteristics, coupling mechanism, advantages and disadvantages, and future prospect of NCAM in specific target identification and validation.

β3 adrenergic receptor activation alleviated PM2.5-induced hepatic lipid deposition in mice

Increasing energy expenditure through activation of hepatocytes is a potential approach to treat fine particulate matter (PM2.5) induced metabolic-associated fatty liver disease (MAFLD). Beta-3 adrenergic receptor (β3-AR) agonists could stimulate brown adipose tissue (BAT) energy expenditure, but it has never been investigated in MAFLD. The objective of this study is to explore the therapeutic effects of administering CL-316,243, a selective agonist of β3-AR, on hepatic lipid metabolism disturbances induced by PM2.5. Firstly, C57BL/6 N mice were intraperitoneally injected with CL-316,243 for one week. CL-316,243 significantly upregulated expression of β3-AR in the liver, accompanied with reduced serum triglyceride (TG) and free fatty acids (FFA). Next, mice were subjected to PM2.5 exposure for 4 weeks, and CL-316,243 was daily intraperitoneally injected in the fourth week of PM2.5 exposure. Exposure to PM2.5 led to a significant increase in hepatic TG and monounsaturated fatty acids (MUFAs), accompanied with elevated activity of SCD1, increased levels of TG synthesis enzymes and inhibited COX4 activity. Furthermore, the administration of CL-316,243 alleviated PM2.5-induced hepatic lipid deposition by enhancing SCD1 activity, TG lipolysis, fatty acid oxidation and TG synthesis via β3-AR/PKA/CREB/PPAR signaling pathway. Therefore, β3-AR activation may serve as a potential therapeutic approach for PM2.5 exposure-induced MAFLD.

Konjac glucomannan attenuate high-fat diet-fed obesity through enhancing β-adrenergic-mediated thermogenesis in inguinal white adipose tissue in mice

Konjac glucomannan (KGM) has been reported to prevent high-fat diet-induced obesity, and we study investigated whether dietary supplementation with KGM can prevent obesity by increasing energy expenditure in inguinal white adipose tissue (iWAT) of high-fat diet (HF) -fed mice. Weaned mice fed the control diet (Con), HF, or HF plus KGM (8%, w/w, HFK) were divided into three groups. The results showed that 10-week supplementation with KGM significantly reduced partial adipose tissue weight and body weight, and improved glucose tolerance. Compared to the HF group, plasma lipid concentrations in the HFK group were greatly decreased to the control level. Moreover, transcriptomic research has shown that genes that are mainly associated with energy and lipid metabolism are significantly altered in iWAT. Mechanistically, KGM stimulated thermogenesis by promoting the expression of uncoupling protein-1 (UCP1) and the β3-adrenergic receptor (ADR3β). Taken together, our results suggest that dietary supplementation with konjac glucomannan can effectively alleviate obesity induced by a high-fat diet by activating ADR3β-mediated iWAT thermogenesis. Dietary supplementation with KGM can effectively alleviate high fat diet- induced obesity mice by via activating ADR3β-mediated thermogenesis of iWAT.

Aurantio-obtusin ameliorates obesity by activating PPARα-dependent mitochondrial thermogenesis in brown adipose tissues

Obesity contributes to the progression of various chronic diseases, and shortens life expectancy. With abundant mitochondria, brown adipose tissue (BAT) dissipates energy through heat to limit weight gain and metabolic dysfunction in obesity. Our previous studies have shown that aurantio-obtusin (AO), a bioactive ingredient in Chinese traditional medicine Cassiae semen significantly improves hepatic lipid metabolism in a steatotic mouse model. In the current study we investigated the effects of AO on lipid metabolism in the BAT of diet-induced obesity mice and in oleic acid and palmitic acid (OAPA)-stimulated primary mature BAT adipocytes. Obese mice were established by feeding a HFHS diet for 4 weeks, and then administered AO (10 mg/kg, i.g.) for another 4 weeks. We showed that AO administration significantly increased the weight of BAT and accelerated energy expenditure to protect the weight increase in the obese mice. Using RNA sequencing and molecular biology analysis we found that AO significantly enhanced mitochondrial metabolism and UCP1 expression by activating PPARα both in vivo and in vitro in the primary BAT adipocytes. Interestingly, AO administration did not improve metabolic dysfunction in the liver and white adipose tissue of obese mice after interscapular BAT excision. We demonstrated that low temperature, a trigger of BAT thermogenesis, was not a decisive factor for AO to stimulate the growth and activation of BATs. This study uncovers a regulatory network of AO in activating BAT-dependent lipid consumption and brings up a new avenue for the pharmaceutical intervention in obesity and related comorbidities.

Oxymatrine relieves high-fructose/fat-induced obesity via reprogramming the activity of lipid metabolism-related enhancer

Introduction

Emerging evidence demonstrates that the high-fructose and high-fat diet (HFHF) induced obesity and fatty liver disease has become one of the most common metabolic disorders worldwide. Therefore, innovative investigations on compounds targeting obesity and fatty liver diseases are urgently needed.

Methods

The high-throughput natural compounds screen was performed to screen the important compounds. A rat HFHF model was constructed, the regulatory function of Oxymatrine in HFHF-induced obesity was further explored.

Results

We identified Oxymatrine, a natural compound extracted from Sophora flavescens, showed a potential compacity in high-fat diet-induced fatty liver disease. We found that oxymatrine significantly inhibited HFHF-induced obesity using a rat HFHF model. Additionally, we found that oxymatrine altered the enhancer landscape of subcutaneous adipose tissues by ChIP-seq analysis using antibodies against the H3K27ac histone modification. Motif enrichment analysis showed the Smad motif was significantly enriched in enhancers altered post-oxymatrine treatment. Further chromatin immunoprecipitation-quantitative PCR (ChIP-qPCR) analysis and luciferase reporter assays showed oxymatrine alters the binding of Smad3 on the enhancer regions of B-cell lymphoma 2 (Bcl2) and the enhancer activity of Bcl2.

Discussion

Together, our study highlighted oxymatrine could suppress high-fructose and high-fat diet-induced obesity by inhibiting the suppressor of mothers against decapentaplegic 3 (Smad3) binding on obesity-related enhancers.

Influence of Polyphenols on Adipose Tissue: Sirtuins as Pivotal Players in the Browning Process

Adipose tissue (AT) can be classified into two different types: (i) white adipose tissue (WAT), which represents the largest amount of total AT, and has the main function of storing fatty acids for energy needs and (ii) brown adipose tissue (BAT), rich in mitochondria and specialized in thermogenesis. Many exogenous stimuli, e.g., cold, exercise or pharmacological/nutraceutical tools, promote the phenotypic change of WAT to a beige phenotype (BeAT), with intermediate characteristics between BAT and WAT; this process is called "browning". The modulation of AT differentiation towards WAT or BAT, and the phenotypic switch to BeAT, seem to be crucial steps to limit weight gain. Polyphenols are emerging as compounds able to induce browning and thermogenesis processes, potentially via activation of sirtuins. SIRT1 (the most investigated sirtuin) activates a factor involved in mitochondrial biogenesis, peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), which, through peroxisome proliferator-activated receptor γ (PPAR-γ) modulation, induces typical genes of BAT and inhibits genes of WAT during the transdifferentiation process in white adipocytes. This review article aims to summarize the current evidence, from pre-clinical studies to clinical trials, on the ability of polyphenols to promote the browning process, with a specific focus on the potential role of sirtuins in the pharmacological/nutraceutical effects of natural compounds.

Corylin accelerated wound healing through SIRT1 and PI3K/AKT signaling: a candidate remedy for chronic non-healing wounds

Introduction: Chronic non-healing wound is a considerable clinical challenge and research into the discovery of novel pro-healing agents is underway as existing therapeutic approaches cannot sufficiently meet current needs. Method: We studied the effects of corylin in cell line fibroblasts and macrophages by Western blots, PCR, Flow cytometry assay, Immunofluorescence. Results: We showed that corylin, a main flavonoid extracted from Psoralea corylifolia L, reduced inflammatory responses, promoted collagen deposition, and accelerated the healing of full-thickness skin wounds in mice. Exploration of the underlying mechanisms showed that corylin activated the PI3K/AKT signaling, leading to fibroblasts' migration, proliferation, and scratch healing. Corylin also activated sirtuin 1 (SIRT1) signaling, enhanced the deacetylation and cytoplasmic translocation of NF-κB p65, and therefore reduced lipopolysaccharide (LPS)-induced inflammatory responses in macrophages. Furthermore, inhibition of PI3K/AKT and sirtuin 1 pathway with LY294002 and EX527 prevent the therapeutic potency of corylin against chronic wounds. Conclusion: In summary, our results suggested that corylin may be a candidate for the development of novel pro-healing agents.

PTPN2 targets TAK1 for dephosphorylation to improve cellular senescence and promote adipose tissue browning in T2DM

Introduction: The energy imbalance when energy intake exceeds expenditure acts as an essential factor in the development of insulin resistance (IR). The activity of brown adipose tissue, which is involved in the dissipation of energy via heat expenditure decreases under type 2 diabetic mellitus (T2DM) state when the number of pathological aging adipocytes increases. Protein tyrosine phosphatase non-receptor type 2 (PTPN2) regulates several biological processes by dephosphorylating several cellular substrates; however, whether PTPN2 regulates cellular senescence in adipocytes and the underlying mechanism has not been reported. Methods: We constructed a model of type 2 diabetic mice with PTPN2 overexpression to explore the role of PTPN2 in T2DM. Results: We revealed that PTPN2 facilitated adipose tissue browning by alleviating pathological senescence, thus improving glucose tolerance and IR in T2DM. Mechanistically, we are the first to report that PTPN2 could bind with transforming growth factor-activated kinase 1 (TAK1) directly for dephosphorylation to inhibit the downstream MAPK/NF-κB pathway in adipocytes and regulate cellular senescence and the browning process subsequently. Discussion: Our study revealed a critical mechanism of adipocytes browning progression and provided a potential target for the treatment of related diseases.

Leaf Extract of Perilla frutescens (L.) Britt Promotes Adipocyte Browning via the p38 MAPK Pathway and PI3K-AKT Pathway

The leaf of Perilla frutescens (L.) Britt (PF) has been reported to negatively affect adipocyte formation, inhibit body-fat formation, and lower body weight. However, its effect on adipocyte browning remains unknown. Thus, the mechanism of PF in promoting adipocyte browning was investigated. The ingredients of PF were acquired from the online database and filtered with oral bioavailability and drug-likeness criteria. The browning-related target genes were obtained from the Gene Card database. A Venn diagram was employed to obtain the overlapped genes that may play a part in PF promoting adipocyte browning, and an enrichment was analysis conducted based on these overlapped genes. A total of 17 active ingredients of PF were filtered, which may regulate intracellular receptor-signaling pathways, the activation of protein kinase activity, and other pathways through 56 targets. In vitro validation showed that PF promotes mitochondrial biogenesis and upregulates brite adipocyte-related gene expression. The browning effect of PF can be mediated by the p38 MAPK pathway as well as PI3K-AKT pathway. The study revealed that PF could promote adipocyte browning through multitargets and multipathways. An in vitro study validated that the browning effect of PF can be mediated by both the P38 MAPK pathway and the PI3K-AKT pathway.

Insights into β3-adrenoceptor agonism through comprehensive in silico investigation

Research onβ₃-AR, the new member of the adrenoceptor family, is in its infancy and few β₃-AR agonists have been approved for marketing to date. Meanwhile, β₃-AR exhibited obvious species differences in pharmacological properties, such as between human and animals, however, the 3D structure of human β₃-AR has not been published, which makes it difficult to understand the interaction between human β₃-AR and its agonists. Herein, binding patterns of β₃-AR agonists are explored starting from the Alphafold predicted structural model, and the obtained model was optimized by using molecular dynamics simulations. Moreover, the human β₃-AR and its agonists were subjected to molecular docking, dynamics simulations, binding free energy calculations and pharmacophore modeling to elucidate the characteristics of human β₃-AR activity pockets and agonist conformational relationships, including a hydrophobic group, a positively charged group as well as two hydrogen-bonded donors, which provide comprehensive insights into the interactions between human β₃-AR and its agonists.

The multifaceted roles of natural products in mitochondrial dysfunction

Mitochondria are the primary source of energy production in cells, supporting the metabolic demand of tissue. The dysfunctional mitochondria are implicated in various diseases ranging from neurodegeneration to cancer. Therefore, regulating dysfunctional mitochondria offers a new therapeutic opportunity for diseases with mitochondrial dysfunction. Natural products are pleiotropic and readily obtainable sources of therapeutic agents, which have broad prospects in new drug discovery. Recently, many mitochondria-targeting natural products have been extensively studied and have shown promising pharmacological activity in regulating mitochondrial dysfunction. Hence, we summarize recent advances in natural products in targeting mitochondria and regulating mitochondrial dysfunction in this review. We discuss natural products in terms of their mechanisms on mitochondrial dysfunction, including modulating mitochondrial quality control system and regulating mitochondrial functions. In addition, we describe the future perspective and challenges in the development of mitochondria-targeting natural products, emphasizing the potential value of natural products in mitochondrial dysfunction.

Emerging role of aging in the progression of NAFLD to HCC

With the aging of global population, the incidence of nonalcoholic fatty liver disease (NAFLD) has surged in recent decades. NAFLD is a multifactorial disease that follows a progressive course, ranging from simple fatty liver, nonalcoholic steatohepatitis (NASH) to liver cirrhosis and hepatocellular carcinoma (HCC). It is well established that aging induces pathological changes in liver and potentiates the occurrence and progression of NAFLD, HCC and other age-related liver diseases. Studies of senescent cells also indicate a pivotal engagement in the development of NAFLD via diverse mechanisms. Moreover, nicotinamide adenine dinucleotide (NAD⁺), silence information regulator protein family (sirtuins), and mechanistic target of rapamycin (mTOR) are three vital and broadly studied targets involved in aging process and NAFLD. Nevertheless, the crucial role of these aging-associated factors in aging-related NAFLD remains underestimated. Here, we reviewed the current research on the roles of aging, cellular senescence and three aging-related factors in the evolution of NAFLD to HCC, aiming at inspiring promising therapeutic targets for aging-related NAFLD and its progression.

Atractylenolide III from Atractylodes macrocephala Koidz promotes the activation of brown and white adipose tissue through SIRT1/PGC-1α signaling pathway

BACKGROUND

Hypothermia is a complex pathophysiological response that can be life-threatening in low-temperature environment because of impaired thermoregulation. However, there is currently no clinically effective drugs that can prevent or treat this disease. Brown adipose tissue (BAT) activation or browning of white adipose tissue (WAT) is a promising therapeutic strategy to prevent or treat hypothermia. Atractylodes macrocephala Koidz extract (AE) and its active compound Atractylenolide III (AIII) has been reported to regulate glycolipid metabolism, which might be relevant to BAT activation. However, the thermogenic effect and mechanism of AE and AIII on adipose tissues have not been explored yet. Therefore, this study firstly investigated the role of AE and AIII on hypothermia by promoting heat production of BAT and WAT.

PURPOSE

To explore the anti-cold effect of AE and AIII in cold exposure model and explore their biological function and mechanism underlying thermogenesis.

METHODS

The effect of thermogenesis and anti-hypothermia of AE and AIII on C57BL/6J mice were evaluated with several experiment in cold environment, such as toxicity test, cold exposure test, metabolism estimation, histology and immunohistochemistry, and protein expression. Additionally, BAT, inguinal WAT (iWAT) and brown adipocytes were utilized to explore the mechanism of AE and AIII on thermogenesis in vivo and in vitro. Finally, SIRT1 agonist and inhibitor in brown adipocytes to verify that AIII activated BAT through SIRT1/PGC-1α pathway.

RESULTS

Both AE and AⅢ could significantly maintain the core body temperature and body surface temperature of mice during cold exposure. Besides, AE and AⅢ could significantly improve the capacity of total antioxidant and glucose, lipid metabolism of mice. In addition, AE and AIII reduced mitochondrial membrane potential and ATP content both in BAT and brown adipocytes, and decreased the size of lipid droplets. Moreover, AE and AⅢ promoted the expression of proteins related to heat production in BAT and iWAT. And AIII might activate BAT via SIRT1/PGC-1α pathway.

CONCLUSION

AE and AⅢ were potential candidate drugs that treated hypothermia by improving the heat production capacity of the mice. Mechanistically, they may activate SIRT1/PGC-1α pathway, thus enhancing the function of BAT, and promoting the browning of iWAT, to act as anti-hypothermia candidate medicine.

Antiobesity Potential of Bioactive Constituents from Dichloromethane Extract of Psoralea corylifolia L. Seeds

Purpose

Effectively controlling the accumulation of adipose tissue can be a therapeutic strategy for treating obesity, which is a global problem. The present study was designed for comparative assessment of in vitro antiobesity activities of the Psoralea corylifolia-dichloromethane seed extract (DCME) and the isolated phytochemicals, bakuchiol, isopsoralen, and psoralen, through antiadipogenesis and pancreatic lipase (PL) inhibition assays. Material and Methods. In vitro pancreatic lipase activity was determined spectrophotometrically by measuring the hydrolysis of p-nitrophenyl butyrate (p-NPB) to p-nitrophenol at 405 nm, and adipogenesis was assayed in 3 T3-L1 adipocytes (by using Oil Red O staining) using P. corylifolia-dichloromethane seed extract (DCME) and individual compounds, isolated from the extract.

Result

Antilipase as well as antiadipogenesis activity was displayed by both the DCME and the compounds. Maximum antilipase property was recorded in DCME (26.02 ± .041%) at 100 μg/ml, while, among the isolated compounds, bakuchiol exhibited a higher activity (24.2 ± 0.037%) at 100 μg/ml concentration, compared to other isolates. DCME was found to exhibit antiadipogenesis property, 75 ± 0.003% lipid accumulation, compared to the control at 100 μg/ml dose. Bakuchiol, isopsoralen, and psoralen inhibited the lipid accumulation in 3T3-L1 preadipocytes, 78.06 ± 0.002%, 80.91 ± 0.004%, and 80.91 ± 0.001%, respectively, lipid accumulation in comparison to control at 25 μM dose.

Conclusion

The present study highlights the antiobesity potential of P. corylifolia and its active constituents. Thus, it can be concluded that P. corylifolia has the potential to treat obesity and related diseases; however, further research on dose standardization and clinical trials are required.

Effects of two triterpenoids from Nigella sativa seeds on insulin resistance of 3T3-L1 adipocytes

Insulin resistance (IR) is a physiological abnormality that occurs when insulin fails to activate the signal transduction pathway in target organs. It was found that supplementation of Nigella sativa seeds with oral antidiabetic medicines helps improve blood glucose control by enhanced β cells activity and alleviation of IR. However, the activities and related mechanisms of phytochemicals from N. sativa seeds have not been thoroughly explored. In this study, the effects of two triterpenoids, 3-O-[β-D-xylopyranose-(1→3)-α-L-rhamnose-(1→2)-α-L-arabinose]-28-O-[α-L-rhamnose-(1→4)-β-D-glucopyranose-L-(1→6)-β-D-glucopyranose]-hederagenin (Hxrarg) and 3-O-[β-D-xylopyranose-(1→3)-α-L-rhamnose-(1→2)-α-L-arabinose]-hederagenin (Hxra), on IR were studied by 3T3-L1 adipocytes model. The results demonstrated that Hxrarg and Hxra inhibited maturation of 3T3-L1 preadipocytes, dramatically stimulated glucose uptake of IR-3T3-L1 adipocytes, promoted transcription of IRS, AKT, PI-3K, and GLUT4 mRNA. Western Blot results suggested that Hxrarg and Hxra were able to markedly up-regulate expression of p-IRS, p-AKT, PI-3K, and GLUT4 proteins. These findings could provide a basic foundation for the continued development and application of N. sativa in medicine and functional foods.

The Underexplored Dimensions of Nutritional Hormesis

PURPOSE OF REVIEW

Hormesis is biphasic response wherein low and high doses of chemical and nutrient confer beneficial and toxic effects respectively, typically in a U-shaped manner. Hormesis is intricately related to bioenergetic state of a cell, and therefore, nutrition impacts it. Excessive nutrition can halt the endogenous antioxidant synthesis leading to cytotoxic effects. While low and optimum doses of the same bring about hormetic stimulation that can exalt the antioxidant response and reduce susceptibility towards degenerative diseases. The sirtuin family of proteins is triggered by mild stress of calorie restriction and exerts hormesis. Similarly, several phytochemicals and micronutrients are known to bring about health benefits at optimum dose and deleterious effects at high doses. Despite this attribute, nutritional hormesis is not very well researched upon because the magnitude of hormetic effect observed is generally quite modest. There is no precise regulation of optimal intake of certain foods to witness hormesis and no characterization of any biomarker that reports stress responses at various doses above or below optimal intakes. There is a major gap in research between nutrition and hormesis being affected by sirtuin family of proteins, phytochemicals, and micronutrients.

RECENT FINDINGS

Mild stress of calorie restriction elevates sirtuin protein and effect of sirtuin protein on hormesis has been recently reported. More foods that enhance sirtuin protein, phytochemicals, and micronutrients need to be explored in relation to hormesis and associated health benefits.

Recent advances in natural anti-obesity compounds and derivatives based on in vivo evidence: A mini-review

Obesity is not only viewed as a chronic aggressive disorder but is also associated with an increased risk for various diseases. Nonetheless, new anti-obesity drugs are an urgent need since few pharmacological choices are available on the market. Natural compounds have served as templates for drug discovery, whereas modified molecules from the leads identified based on in vitro models often reveal noncorresponding bioactivity between in vitro and in vivo studies. Therefore, to provide inspiration for the exploration of innovative anti-obesity agents, recent discoveries of natural anti-obesity compounds with in vivo evidence have been summarized according to their chemical structures, and the comparable efficacy of these compounds is categorized using animal models. In addition, several synthetic derivatives optimized from the phytochemicals are also provided to discuss medicinal chemistry achievements guided by natural sources.

Flavonoids as Sirtuin Modulators

Sirtuins (SIRTs) are described as NAD+-dependent deacetylases, also known as class III histone deacetylases. So far, seven sirtuin genes (SIRTS 1-7) have been identified and characterized in mammals and also known to occur in bacteria and eukaryotes. SIRTs are involved in various biological processes including endocrine system, apoptosis, aging and longevity, diabetes, rheumatoid arthritis, obesity, inflammation, etc. Among them, the best characterized one is SIRT1. Actually, small molecules seem to be the most effective SIRT modulators. Flavonoids have been reported to possess many positive effects favrable for human health, while a relatively less research has been reported so far on their funcions as SIRT modulation mechanisms. In this regard, we herein aimed to focus on modulatory effects of flavonoids on SIRTs as the most common secondary metabolites in natural products. Our literature survey covering the years of 2006-2021 pointed out that flavonoids frequently interact with SIRT1 and SIRT3 followed by SIRT6. It can be also concluded that some popular flavonoid derivatives, e.g. resveratrol, quercetin, and catechin derivatives came forward in terms of SIRT modulation.

Rutin-activated adipose tissue thermogenesis is correlated with increased intestinal short-chain fatty acid levels

The activation of thermogenic programs in brown adipose tissue (BAT) and white adipose tissue (WAT) provides a promising approach to increasing energy expenditure during obesity and diabetes treatment. Although evidence has been found that rutin activates BAT against obesity and type 2 diabetes mellitus (T2DM), its potential mechanism is not completely understood. In this study, we focused on the potential modulating effect of rutin on short-chain fatty acids (SCFAs) and the thermogenesis of BAT and WAT, aiming to elucidate the molecular mechanism of rutin in the treatment of obesity and T2DM. The results showed that rutin could significantly reduce the body weight and fasting blood glucose, inhibit fat accumulation, relieve hepatic steatosis and ameliorate the disorder of glycolipid metabolism in db/db mice. Moreover, rutin also increased the expression of uncoupling protein 1 (Ucp1) and other thermogenic genes and proteins in BAT and inguinal WAT (IWAT), indicating that rutin activated BAT and induced browning of IWAT. Importantly, rutin markedly enhanced the concentration of SCFAs (acetate, propionate and butyrate) and SCFA-producing enzymes (acetate kinase (ACK), methylmalonyl-CoA decarboxylase (MMD) and butyryl-CoA (BUT)) in feces of db/db mice. In addition, rutin significantly increased the mRNA expression of monocarboxylate transporter 1 (Mct1), catabolic enzyme acyl-CoA medium-chain synthetase 3 (Acsm3), carnitine palmitoyl transferase 1α (Cpt-1α) and Cpt-1β genes in BAT and IWAT of db/db mice, which is conducive to inducing adipocyte thermogenesis. In summary, our findings revealed that rutin played a variety of regulatory roles in improving glucose and lipid metabolism disorders, reducing hepatic steatosis, inducing browning of IWAT and activating BAT, which has potential therapeutic significance for the treatment of obesity and T2DM. Mechanistically, rutin activates the thermogenesis of BAT and IWAT, which may be associated with increasing the concentration of SCFAs.

The flavonoid corylin exhibits lifespan extension properties in mouse

In the long history of traditional Chinese medicine, single herbs and complex formulas have been suggested to increase lifespan. However, the identification of single molecules responsible for lifespan extension has been challenging. Here, we collected a list of traditional Chinese medicines with potential longevity properties from pharmacopeias. By utilizing the mother enrichment program, we systematically screened these traditional Chinese medicines and identified a single herb, Psoralea corylifolia, that increases lifespan in Saccharomyces cerevisiae. Next, twenty-two pure compounds were isolated from Psoralea corylifolia. One of the compounds, corylin, was found to extend the replicative lifespan in yeast by targeting the Gtr1 protein. In human umbilical vein endothelial cells, RNA sequencing data showed that corylin ameliorates cellular senescence. We also examined an in vivo mammalian model, and found that corylin extends lifespan in mice fed a high-fat diet. Taken together, these findings suggest that corylin may promote longevity.

Modulation of Gut Microbiota Combined with Upregulation of Intestinal Tight Junction Explains Anti-Inflammatory Effect of Corylin on Colitis-Associated Cancer in Mice

Inflammatory bowel disease (IBD) involves chronic inflammation, loss of epithelial integrity, and gastrointestinal microbiota dysbiosis, resulting in the development of a colon cancer known as colitis-associated colorectal cancer (CAC). In this study, we evaluated the effects of corylin in a mouse model of dextran sodium sulfate (DSS)-induced colitis. The results showed corylin could improved the survival rate and colon length, maintained body weight, and ameliorated the inflammatory response in the colon. Then, we further identified the possible antitumor effects after 30-day treatment of corylin on an azoxymethane (AOM)/DSS-induced CAC mouse model. Biomarkers associated with inflammation, the colon tissue barrier, macrophage polarization (CD11c, CCR7, CD163, and CD206), and microbiota dysbiosis were monitored in the AOM/DSS group versus corylin groups. Corylin downregulated pro-inflammatory cytokines (TNF-α, IFN-γ, IL-1β, and IL-6) mRNA expression and inflammatory signaling-associated markers (TLR4, MyD88, AP-1, CD11b, and F4/80). In addition, a colon barrier experiment revealed that epithelial cell proliferation of the mucus layer (Lgr5, Cyclin D1, and Olfm4) was downregulated and tight junction proteins (claudin-1 and ZO-1) were upregulated. Furthermore, the Firmicutes/Bacteroidetes ratio changed with corylin intervention, and the microbial diversity and community richness of the AOM/DSS mice were improved by corylin. The comparative analysis of gut microbiota revealed that Bacteroidetes, Patescibacteria, Candidatus Saccharimonas, Erysipelatoclostridium, and Enterorhabdus were significantly increased but Firmicutes, Turicibacter, Romboutsia, and Blautia decreased after corylin treatment. Altogether, corylin administration showed cancer-ameliorating effects by reducing the risk of colitis-associated colon cancer via regulation of inflammation, carcinogenesis, and compositional change of gut microbiota. Therefore, corylin could be a novel, potential health-protective, natural agent against CAC.

Exercise and/or Cold Exposure Alters the Gene Expression Profile in the Fat Body and Changes the Heart Function in Drosophila

The major reason of human morbidity and mortality is obesity and related diseases. Brown adipose tissue (BAT) is associated with low total adipose tissue content and a lower risk of type 2 diabetes mellitus. Studies have shown that exercise and cold expose may induce browning. In this study, we verified (1) whether exercise and/or cold exposure can improve the expression level of ucp4c, serca, ampkα, camkII, sirt1, octβ3r, and hamlet; (2) if these interventions can save cardiac dysfunction induced by a high-fat diet (HFD) in Drosophila. w1118 (wild-type) virgin female flies collected within 8 h after eclosion were divided into eight groups: the normal feed control group (NFD-C), the normal feed exercise group (NFD-E), the normal feed cold exposure group (NFD-CA), the normal feed exercise/cold exposure group (NFD-EC), the HFD control group (HFD-C), the HFD exercise group (HFD-E), the HFD cold exposure group (HFD-CA), and the HFD exercise/cold exposure group (HFD-EC). After exercise and/or cold exposure for 7 days, the mRNA expression levels of ucp4c, serca, ampkα, camk II, sirt1, octβ3r, and hamlet were tested by qRT-PCR, and m-mode was used to assess cardiac function. In addition, we assessed the triacylglycerol (TAG) levels, motor ability, fat mass (by Oil Red O [ORO] staining), and morphological features. The results of TAG, ORO staining, and morphological features all indicate that after interventions, body size of Drosophila was smaller compared with the control group, irrespective of the feeding patterns. The mRNA expression levels of ucp4c, serca, octβ3r, hamlet, ampkα, camkII, and sirt1 were changed to varying degrees under different intervention states (exercise and/or cold exposure). Cold exposure and exercise/cold exposure partly improved cardiac function and the normal fruit flies' cardiac function and exercise ability. However, after exercise intervention, exercise ability and heart function were improved in both HFD and normal-fat diet (NFD) fruit flies. In conclusion, different intervention states (exercise and/or cold exposure) can change the mRNA expression levels of ucp4c, serca, octβ3r, hamlet, ampkα, camkII, and sirt1. Exercise is the most effective way to restore HFD-induced cardiac dysfunction.

Corylin Ameliorates LPS-Induced Acute Lung Injury via Suppressing the MAPKs and IL-6/STAT3 Signaling Pathways

Acute lung injury (ALI) is a high mortality disease with acute inflammation. Corylin is a compound isolated from the whole plant of Psoralea corylifolia L. and has been reported to have anti-inflammatory activities. Herein, we investigated the therapeutic potential of corylin on lipopolysaccharides (LPS)-induced ALI, both in vitro and in vivo. The levels of proinflammatory cytokine secretions were analyzed by ELISA; the expressions of inflammation-associated proteins were detected using Western blot; and the number of immune cell infiltrations in the bronchial alveolar lavage fluid (BALF) were detected by multicolor flow cytometry and lung tissues by hematoxylin and eosin (HE) staining, respectively. Experimental results indicated that corylin attenuated LPS-induced IL-6 production in human bronchial epithelial cells (HBEC3-KT cells). In intratracheal LPS-induced ALI mice, corylin attenuated tissue damage, suppressed inflammatory cell infiltration, and decreased IL-6 and TNF-α secretions in the BALF and serum. Moreover, it further inhibited the phosphorylation of mitogen-activated protein kinases (MAPKs), including p-JNK, p-ERK, p-p38, and repressed the activation of signal transducer and activator of transcription 3 (STAT3) in lungs. Collectively, our results are the first to demonstrate the anti-inflammatory effects of corylin on LPS-induced ALI and suggest corylin has significant potential as a novel therapeutic agent for ALI.

Characterization of β-adrenergic receptors in bovine intramuscular and subcutaneous adipose tissue: comparison of lubabegron fumarate with β-adrenergic receptor agonists and antagonists

Chinese hamster ovary cell constructs expressing either the β ₁-, β ₂- or β ₃-adrenergic receptor (AR) were used to determine whether a novel β-AR modulator, lubabegron fumarate (LUB; Experior, Elanco Animal Health) might exert greater potency for a specific β-AR subtype. EC₅₀ values calculated based on cAMP accumulation in dose response curves indicate that LUB is highly selective for the β ₃-AR subtype, with an EC₅₀ of 6 × 10^–9 M, with no detectible agonistic activity at the β ₂-AR. We hypothesized that the accumulation of lipolytic markers would reflect the agonist activity at each of the β-receptor subtypes of the specific ligand; additionally, there would be differences in receptor subtype expression in subcutaneous (s.c.) and intrmuscular (i.m.) adipose tissues. Total RNA was extracted from adipose tissue samples and relative mRNA levels for β ₁-, β₂-, and β ₃-AR were measured using real-time quantitative polymerase chain reaction. Fresh s.c. and i.m. adipose tissue explants were incubated with isoproterenol hydrochloride (ISO; β-AR pan-agonist), dobutamine hydrochloride (DOB; specific β ₁-AA), salbutamol sulfate (SAL; specific β ₂-AA), ractopamine hydrochloride (RAC), zilpaterol hydrochloride (ZIL), BRL-37344 (specific β ₃-agonist), or LUB for 30 min following preincubation with theophylline (inhibitor of phosphodiesterase). Relative mRNA amounts for β ₁-, β ₂-, and β ₃-AR were greater (P < 0.05) in s.c. than in i.m. adipose tissue. The most abundant β-AR mRNA in both adipose tissues was the β ₂-AR (P < 0.05), with the β ₁- and β ₃-AR subtypes being minimally expressed in i.m. adipose tissue. ISO, RH, and ZH stimulated the release of glycerol and nonesterified fatty acid (NEFA) from s.c. adipose tissue, but these β-AR ligands did not alter concentrations of these lipolytic markers in i.m. adipose tissue. LUB did not affect glycerol or NEFA concentrations in s.c. or i.m. adipose tissue, but attenuated (P < 0.05) the accumulation of cAMP mediated by the β ₁- and β ₂-AR ligands DOB and SAL in s.c. adipose tissue. Collectively, these data indicate that bovine i.m. adipose tissue is less responsive than s.c. adipose tissue to β-adrenergic ligands, especially those that are agonists at the β ₁- and β₃-receptor subtypes. The minimal mRNA expression of the β ₁- and β ₃ subtypes in i.m. adipose tissue likely limits the response potential to agonists for these β-AR subtypes.

The Anti-Obesity Effect of Traditional Chinese Medicine on Lipid Metabolism

With the improvement of living conditions and the popularity of unhealthy eating and living habits, obesity is becoming a global epidemic. Obesity is now recognized as a disease that not only increases the risk of metabolic diseases such as type 2 diabetes (T2D), non-alcoholic fatty liver disease (NAFLD), cardiovascular disease (CVD), and cancer but also negatively affects longevity and the quality of life. The traditional Chinese medicines (TCMs) are highly enriched in bioactive compounds and have been used for the treatment of obesity and obesity-related metabolic diseases over a long period of time. In this review, we selected the most commonly used anti-obesity or anti-hyperlipidemia TCMs and, where known, their major bioactive compounds. We then summarized their multi-target molecular mechanisms, specifically focusing on lipid metabolism, including the modulation of lipid absorption, reduction of lipid synthesis, and increase of lipid decomposition and lipid transportation, as well as the regulation of appetite. This review produces a current and comprehensive understanding of integrative and systematic mechanisms for the use of TCMs for anti-obesity. We also advocate taking advantage of TCMs as another therapy for interventions on obesity-related diseases, as well as stressing the fact that more is needed to be done, scientifically, to determine the active compounds and modes of action of the TCMs.