Effect and Mechanism of Total Saponins from Panax Japonicus on White Adipose Tissue Browning/Brown Adipose Tissue Activation in High-fat Diet-induced Mice / 中国实验方剂学杂志

ObjectiveTo investigate the effect and mechanism of total saponins from Panax japonicus （TSPJ） on white adipose tissue （WAT） browning/brown adipose tissue （BAT） activation in C57BL6/J male mice fed on a high-fat diet （HFD）. MethodThirty-two C57BL6/J male mice （8-week-old） were randomly divided into a normal group， a model group， a low-dose TSPJ group， and a high-dose TSPJ group. The mice in the low-dose and high-dose TSPJ groups were given TSPJ for four months by gavage at 25， 75 mg·kg-1·d-1， respectively， and those in the other groups were given 0.5% sodium carboxymethyl cellulose （CMC-Na） accordingly. After four months of feeding， all mice were placed at 4 ℃ for acute cold exposure， and the core body temperature was monitored. Subsequently， all mice were sacrificed， and BAT and inguinal WAT （iWAT） were separated rapidly to detect the corresponding indexes. Hematoxylin-eosin （HE） staining was used to observe the morphological changes in each group. The effect of TSPJ on the mRNA expression of uncoupling protein 1 （UCP1）， fatty acid-binding protein 4 （FABP4）， cytochrome C （CytC）， PR domain-containing protein 16 （PRDM16）， elongation of very long chain fatty acids protein 3 （ELOVL3）， peroxisome proliferator-activated receptor γ （PPARγ）， and peroxisome proliferator-activated receptor-γ coactivator-1α （PGC-1α） in iWAT and BAT was detected by Real-time polymerase chain reaction （Real-time PCR）. Western blot was also used to detect the protein expression of UCP1， PRDM16， PPARγ， and PGC-1α in BAT and iWAT of each group. The effect of TSPJ on UCP1 expression in BAT and iWAT was detected by immunohistochemistry. Result① Compared with the model group， TSPJ could decrease the body weight and proportions of iWAT and BAT in the HFD-induced mice （P<0.05， P<0.01）. ② The body temperature of mice in the model group decreased compared with that in the normal group in the acute cold exposure tolerance test （P<0.05）. The body temperature in the high-dose TSPJ group increased compared with that in the model group （P<0.01）. ③ Compared with the normal group， the model group showed increased adipocyte diameter in iWAT and BAT and decreased number of adipocytes per unit area. Compared with the model group， the TSPJ groups showed significantly reduced cell diameter and increased number of cells per unit area， especially in the high-dose TSPJ group. ④ Compared with the normal group， the model group showed decreased mRNA expression of FABP4， UCP1， CytC， PRDM16， ELOVL3， PGC-1α， and PPARγ in adipose tissues of mice （P<0.05， P<0.01）. Compared with the model group， after intervention with TSPJ， the mRNA expression was significantly up-regulated （P<0.05， P<0.01）. ⑤ Compared with the normal group， the model group showed decreased protein expression of UCP1， PRDM16， PPARγ， and PGC-1α in adipose tissues of mice （P<0.05， P<0.01）. Compared with the model group， after intervention with TSPJ， the protein expression increased significantly （P<0.05， P<0.01）. ConclusionTSPJ could induce the browning of iWAT/BAT activation and enhance adaptive thermogenesis in obese mice induced by HFD. The underlying mechanism may be attributed to the activation of the PPARγ/PGC-1α signaling pathway.

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

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.

Rutin Promotes Browning of 3T3-L1 Preadipocytes and Its Mechanism / 中国实验方剂学杂志

ObjectiveTo investigate the effect of rutin on the browning of 3T3-L1 preadipocytes and the mechanism. MethodCell counting kit-8 （CCK-8） assay was used to detect the effect of different concentration of rutin （3.125， 6.25， 12.5， 25， 50， 100， 200 μmol·L-1） on 3T3-L1 cell activity， and Western blot to examine the effect of rutin （12.5， 25， 50 μmol·L-1） on the expression of thermogenesis-associated proteins uncoupling protein 1 （UCP1）， PR domain containing 16 （PRDM16） and peroxisome proliferator-activated receptor γ coactivator-1α （PGC-1α） in adipocytes. After the optimal concentration of rutin was determined， the effect of rutin on lipid droplet formation in adipocytes was observed based on oil red O staining， and the expression of nuclear respiratory factor 1 （NRF1）， nuclear respiratory factor 2 （NRF2） and mitochondrial transcription factor A （TFAM）， which were the landmark proteins of mitochondrial biosynthesis， was detected by Western blot. ResultCompared with the blank group， 200 μmol·L-1 rutin inhibited 3T3-L1 cell activity （P<0.01）. Compared with the blank group， at the concentration of 12.5， 25， 50 μmol·L-1 rutin significantly promoted the expression of thermogenesis-associated proteins （UCP1， PRDM16， and PGC-1α） （P<0.01）， which was determined as the optimal concentration. Compared with the blank group， 50 μmol·L-1 rutin significantly increased the immunofluorescence intensity of mitochondrial UCP1 protein in 3T3-L1 cells （P<0.01） and the expression of the markers of mitochondrial biosynthesis （NRF1， NRF2， and TFAM） （P<0.01）. In addition， 50 μmol·L-1 rutin significantly inhibited lipid droplet formation of 3T3-L1 adipocytes （P<0.01）. ConclusionRutin inhibited lipid droplet deposition in 3T3-L1 adipocytes and increased the expression of thermogenesis-related proteins （UCP1， PRDM16， and PGC-1α） and markers of mitochondrial biosynthesis （NRF1， NRF2， and TFAM）， thereby inducing the browning of 3T3-L1 adipocytes. This lays a basis for the development of drugs that safely regulate the browning of white cells.

Advances of targeted delivery vectors for inducing browning of white adipose tissue / 药学学报

Obesity has become an important inducer of many public diseases such as diabetes, endocrine disorders, and so on. Anti-obesity treatment has become a hot topic. Inhibiting fat synthesis and promoting fat decomposition are important ways of drug anti-obesity treatment. With the in-depth study of the distribution, morphology and function of adipose tissue, brown adipose tissue containing multi-compartment fat drops and rich mitochondria have attracted people's attention. Beige adipocytes which are similar to brown adipocytes in morphology and function have aroused great interest, such cells can be transformed from white adipocytes by external stimulation or browning agents. This process is called "white fat browning". The expression of promoting energy consumption proteins in these cells increase, so that the function of adipocytes changes from energy storage to energy consumption to increase excessive energy consumption in the body and reduce lipid accumulation. The browning of white adipose tissue has brought new ideas for obesity treatment, but the systemic administration of browning agent has the risk of adverse reactions to non-target tissues such as heart and central nervous system, which limits its application in inducing white fat browning. Browning agents to white adipose tissue can reduce its adverse reactions and improve its bioavailability by constructing a drug delivery system targeting white adipose tissue. In this review, the mechanism on browning of white adipose tissue, the commonly used browning agents and the targeted delivery carriers that induce browning of white adipose tissue are summarized.

Identification of laccase gene family members in peach and its relationship with chilling induced browning / 生物工程学报

The laccase (PpLAC) gene family members in peach fruit were identified and the relationship between their expression pattern and chilling induced browning were investigated. The study was performed using two varieties of peaches with different chilling tolerance, treated with or without exogenous γ-aminobutyric acid (GABA) during cold storage. Twenty-six genes were screened from the peach fruit genome. These genes were distributed on 6 chromosomes and each contained 5-7 exons. The PpLAC gene family members shared relatively similar gene structure and conserved motifs, and they were classified into 7 subgroups based on the cluster analysis. Transcriptome sequencing revealed that the expression levels of PpLAC7 and PpLAC9 exhibited an increasing pattern under low temperature storage, and displayed a similar trend with the browning index of peach fruit. Notably, GABA treatment reduced the degree of browning and inhibited the expression of PpLAC7 and PpLAC9. These results suggested that PpLAC7 and PpLAC9 might be involved in the browning of peach fruit during cold storage.

Research progress on mechanisms of AMPK in diabetes prevention and control / 中国药理学通报

AMP-activated protein kinase (AMPK) is a serine/threonine protein kinase that plays a key role in the maintenance and regulation of energy homeostasis in body. It is an important regulator of energy metabolism. Numerous studies have shown that AMPK plays an important role in the prevention and control of diabetes. AMPK can activate or inhibit a variety of downstream effectors, thereby regulating a variety of physiological activities, including regulating glucose and lipid metabolism, promoting browning of white adipose, anti-inflammatory, antioxidant stress, etc. In this review, the mechanisms of AMPK preventing the occurrence and development of diabetes were reviewed, aiming to provide a reference for the development of safe and effective new AMPK targeting drugs.

Determination of the activity and kinetic parameters of polyphenol oxidase enzyme in crude extracts of some Jordanian plants

The activity and kinetic parameters of the enzyme polyphenol oxidase (PPO) in crude extracts of the fruits ofParadise apple (Pyrus malus L.), cucumber (Cucumis sativus L.), squash (Cucurbita pepo L.), pomegranaterind and seeds (Punica granatum L.), and the leaf of cactus (Opuntia ficus-indica (L.) were investigated. Thehighest browning intensity was found in P. apple, followed by pomegranate seeds and cucumber fruits. Theoptimum activity of the enzyme was shown at pH 7.0 for P. apple and cucurbita, but it was found at pH 6.0 forthe rind and seeds of the pomegranate. The PPO of cactus leaf and cucumber fruits showed two peaks at pH 4.0and 7.0. On the other hand, the optimal temperature found for PPO activity in these plants was around 40°C.A strong correlation with value (R) = 0.9485 between the browning intensity and PPO activity in all studiedsamples was obtained.

Recent developments in natural products for white adipose tissue browning / 中国天然药物

Excess accumulation of white adipose tissue (WAT) causes obesity which is an imbalance between energy intake and energy expenditure. Obesity is a serious concern because it has been the leading causes of death worldwide, including diabetes, stroke, heart disease and cancer. Therefore, uncovering the mechanism of obesity and discovering anti-obesity drugs are crucial to prevent obesity and its complications. Browning, inducing white adipose tissue to brown or beige (brite) fat which is brown-like fat emerging in WAT, becomes an appealing therapeutic strategy for obesity and metabolic disorders. Due to lack of efficacy or intolerable side-effects, the clinical trials that promote brown adipose tissue (BAT) thermogenesis and browning of WAT have not been successful in humans. Obviously, more specific means still need to be developed to activate browning of white adipose tissue. In this review, we summarized seven kinds of natural products (alkaloids, flavonoids, terpenoids, long chain fatty acids, phenolic acids, else and extract) promoting white adipose tissue browning which can ameliorate the metabolic disorders, including obesity, dislipidemia, insulin resistance and diabetes. Since natural products are important drug sources and the browning property plays a significant role in not only obesity treatment but also in type 2 diabetes (T2DM) improvement, natural products of inducing browning may be an irreplaceable drug discovery orientation for obesity, diabetes and even other metabolic disorders.

Withaferin A protecting against high fat diet induced obesity by inducing white adipose tissue browning / 解剖学报

[ Abstract] Objective To investigate the protective effect of withaferin A (WA) against high fat diet induced obesity and its associated mechanism. Methods C57BL / 6 J mice at 8-week of age were divided into two groups. The mice were fed with high fat diet (HFD) and were given an intraperitoneal injection of WA or DMSO (solvent control) . The body weight and food intake of the mice were monitored. One week later, inguinal white adipose tissue (iWAT), interscapular brown adipose tissue (BAT), epididymal white adipose tissue (eWAT) and retroperitoneal white adipose tissue (rWAT) were collected and weighed. Expression levels of the genes associated with white adipose browning were detected in iWAT. HE staining was applied to observe the morphological changes of iWAT. Results The data showed that body weight and fat weight in WA group were significantly lower than those in the control group, and the food intake was not changed significantly. Real-time PCR analysis showed that the expression level of browning related genes in iWAT of the WA group was significantly increased. The result from Western blotting analysis showed that the protein levels of uncoupling protein 1 (UCP1) and peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC1α) increased significantly in iWAT of the WA group. The typical morphological change of adipose browning, such as the multilocular adipocytes was observed in inguinal white adipose tissue of the mice treated with WA by using HE staining and mmunofluorescence assay. Conclusion Taken together, these observations indicate that withaferin A can protect the mice from high fat diet induced obesity by promoting white adipose tissue browning.

Fibroblast growth factor 21 regulates browning of white fat: The role of exercise / 中国组织工程研究

BACKGROUND: Fibroblast growth factor 21 (FGF-21) is a newly discovered metabolic regulator that has been expressed in various tissues and organs such as liver, fat and skeletal muscle. Numerous studies have shown that FGF-21 is involved in the browning of white fat, but there is less review of this aspect worldwide. Especially the mediation of exercise is still controversial. OBJECTIVE: To explore the inducing factors and mechanism of FGF-21 regulating the browning of white fat, especially the effects of exercise on it, in order to provide new targets for the treatment of obesity and related metabolic diseases. METHODS: A computer-based search of CNKI and PubMed databases was performed for relevant articles published from January 2001 to July 2019 using the keywords of “FGF-21, browning, exercise, fat” in Chinese and English, respectively. Finally, 45 eligible articles were included in results analysis according to the inclusion criteria. RESULTS AND CONCLUSION: FGF-21 can enter the blood in autocrine, endocrine and paracrine patterns to regulate glycolipid metabolism, improve insulin resistance, prevent liver disease, and promote the browning of white fat. Exercise can induce the secretion and expression of FGF-21, thereby effectively regulating the activation of brown fat and browning of white fat to achieve fat loss. Due to differences in exercise patterns, exercise intensity, and exercise time, the current process of exercise-mediated FGF-21 involvement in the browning of white fat needs further study.

Study on formation regularity and kinetics of advanced glycation end-products during processing of boiled Cervi Cornu Pantotrichum / 中草药

Objective: To study the formation regularity and kinetic parameters of advanced glycation end-products during the processing of boiled Cervi Cornu Pantotrichum (CCP). Methods: UV-visible spectrophotometry and UPLC-MS/MS method were used to determine the change of browning index and content of typical advanced glycation end-products, Nε-(carboxymethyl) lysine and Nε-(carboxyethyl) lysine, of the processing system of simulated boiled CCP. The formation regularity and kinetic parameters of advanced glycation end-products during the processing of boiled CCP were discussed by constructing glucose and lysine to simulate the Maillard reaction system of CCP processing. Results: The activation energy of browning reaction, Nε-(carboxymethyl) lysine and Nε-(carboxyethyl) lysine reaction during processing of boiled CCP were 5.07, 40.44 and 78.47 kJ/mol, respectively, and all of them were zero-order kinetics. The activation energies of the above reactions in the baking process were 6.72, 89.34 and 164.77 kJ/mol, respectively, and all of them were zero-order kinetics. Compared to the formation of Nε-(carboxymethyl) lysine, the formation of Nε-(carboxyethyl) lysine required higher activation energy and was more difficult to occur. Conclusion: The temperature changed in the baking process has a significantly higher effect on the kinetic parameters of the advanced glycation end-products than in the boiling process. Long-term higher baking temperature resulted in more advanced glycation end-products produced in the boiled CCP. This study provides a solid theoretical basis for the blocking and inhibition strategies of advanced glycation end-products in the processing of CCP, which is also a great significance for the production of green safety CCP and strengthening the safety of traditional Chinese medicine.

Effect of different sulfur fumigation dosages on activity of browning enzymes and chemical constituents of Chrysanthemum morifolium cv. Boju / 中国中药杂志

This study aims to investigate the influence of the different dosages of sulfur on the quality and the browning enzyme activity of Chrysanthemum morifolium cv. Boju. In this experiment,UV-spectrophotometry was used to determine the activities of browning enzymes,including polyphenol oxidase( PPO) and peroxidase( POD),in 7 different dosages of 0,4,8,16,50,150,200 g·kg~(-1)( weight ratio of sulfur/fresh chrysanthemum). A comprehensively comparison of the 7 chemical constituents of C. morifolium cv. Boju fumigated with 7 different dosage of sulfur was conducted by HPLC analysis. In this paper,the results showed that the activities of PPO and POD enzymes decreased significantly in chrysanthemum processed by sulfur fumigation. The activities of PPO and POD enzymes decreased gradually with the increase of sulfur dosage. When the sulfur dosage was higher than 4 g·kg~(-1),the PPO enzyme was significantly reduced. When the sulfur dosage was higher than 8 g·kg~(-1),the PPO enzyme was completely inactivated. The effect of different sulfur dosage s on the chemical composition was investigated. In comparison,it was found that when the sulfur dosage was 8 g·kg~(-1),the content of chlorogenic acid was higher than the 4 g·kg~(-1) and that of the sample without sulfur fumigation. Thereafter,with the increase of the sulfur dosage,the content of chlorogenic acid was unchanged. It was speculated that when harvesting,the tissue of fresh flower was destroyed,which caused the activation of browning enzymes. Afterwards,the sulfur fumigation could significantly reduce the activity of browning enzymes,which prevented the conversion of phenols in the reaction substrates( chlorogenic acid and 3,5-dicaffeoylquninic acid) into terpenoids,and better retained quinic acid components. However,when the sulfur dosage reached 8 g·kg~(-1) or16 g·kg~(-1),the content of quinic acid components were no longer changed,which indicated that the sulfur dosage had reached the saturated dosage. Similarly,when the sulfur dosage was increased,the contents of flavonoid aglycones showed a downward trend except for luteolin-7-O-glucoside. It was speculated that the sulfur fumigation inhibited the activity of hydrolase,which reduced the hydrolysis of flavonoid glycosides to aglycones. However,the reaction mechanism needed further verification. In conclusion,although sulfur fumigation could significantly inhibit browning,different dosages of sulfur had a significant effect on the chemical composition of C. morifolium cv. Boju,which could affect the consistency of quality and the stability of the therapeutic effect. Excessive use of sulfur was likely to cause a large amount of SO2 residues in C. morifolium cv. Boju,Therefore,different Sulphur dosages had a significant effect on the quality of chrysanthemum,which therefore was not recommended in production. A small dose of sulfur could be used to prevent enzymatic browning. When the dosage of sulfur increased to a certain extent or reached a saturation state,a small dose of sulfur is recommended in necessary. In this paper,the correlation between the sulfur dosage,the enzyme activity,and the main chemical constituents of chrysanthemum was clarified. The experimental research provided the guidance for regulating the harvesting processing of chrysanthemum and the harvesting processing,and improving the quality of chrysanthemum.

Role of Ad36 in inducing browning of 3T3-L1 cells / 中华内分泌代谢杂志

Objective@#To investigate the role of adenovirus type 36 (Ad36) in the browning of 3T3-L1 cells.@*Methods@#BODIPY staining was performed on the 0, 2nd, 4th, 6th and 8th days of the cocktail induction (control) group and the cocktail plus Ad36 induction (experimental) group to observe the adipogenesis of 3T3-L1 cells.The mRNA and protein expressions of uncoupling protein-1(Ucp1), ATP synthase, H+ transporting, mitochondrial F1 complex, O subunit (Atp5o), cytochrome c oxidase subunit 5B(Cox5b), and perilipin were detected by real-time PCR and Western-blot.@*Results@#The results of BODIPY staining showed that the lipid droplets in the control group gradually became larger with the differentiation of the cells, while the lipid droplets in the experimental group firstly became larger, and then appeared smaller after Ad36 was added on the fourth day. Compared with the control group, the mRNA and protein expression levels of Ucp1, Atp5o, and Cox5b in the experimental group were significantly increased while the expression level of perilipin was significantly decreased (all P<0.05).@*Conclusion@#During the differentiation of 3T3-L1 cells, Ad36 promotes its browning via increasing the expressions of Ucp1, Atp5o, and Cox5b.

Time-sequential expression of lnc AK079912 during adipose tissue development and browning in mice / 南方医科大学学报

OBJECTIVE@#To investigate the time-sequential expression of a novel long non-coding RNA, lnc AK079912, in metabolically related tissues and during adipose tissue development and browning in mice.@*METHODS@#The interscapular brown adipose tissue (iBAT), subcutaneous white adipose tissue (sWAT), epididymal white adipose tissue (eWAT), liver tissues and muscular tissues were collected from 8-week-old C57BL/6J mice. The iBAT, sWAT and eWAT were also collected from the mice during development (0 day, 21 days, 8 weeks and 6 months after birth) and from 8- to 10-week- mice with cold exposure (4 ℃) and intraperitoneal injections of CL316, 243 (1 μg/g body weight) for 1 to 5 days. Trizol was used to extract the total RNA from the tissues, and RT-qPCR was performed to detect the expressions of lnc AK079912. Isolated mouse preadipocytes in primary culture were induced for adipogenic differentiation for 9 days and then treated with CL316, 243 (2 μmol/L) for different durations (no longer than 24 h); the expression of lnc AK079912 in the cells was detected using RT-qPCR at different time points of the treatment.@*RESULTS@#Lnc AK079912 was highly expressed in mouse adipose tissues, the highest in iBAT, followed by the muscular tissue, but was hardly detected in the liver tissue. The expression level of lnc AK079912 increased progressively in iBAT and sWAT during development of the mice, while its expression in eWAT showed an initial increase followed by a reduction at 8 weeks ( 0.05). The expression of lnc AK079912 was significantly decreased in iBAT and eWAT ( < 0.05) but increased in eWAT from mice with intraperitoneal injection of CL316, 243 for 1 to 5 days ( < 0.05). The expression level in the adipocytes in primary culture was significantly increased in response to treatment with CL316, 243 ( < 0.05).@*CONCLUSIONS@#Lnc AK079912 is highly expressed in mouse adipose tissue, and its expression gradually increases with the development of adipose tissue but with a depot-specific difference. Lnc AK079912 is significantly elevated in the early stage of adipose tissue browning, indicating its important role in the development and browning of adipose tissue.

Effect of cold exposure on browning of white adipose tissues in mice fed with high fat diet / 中国药理学通报

Aim: To observe the effect of cold exposure on browning of white adipose tissues in mice fed with high fat diet. Methods: Male 8-week-old C57BL/6J mice were randomly divided into HFD + 5 °C group and HFD + RT group, after 8 weeks of high-fat diet. Male 8-week-old C57BL/6J mice were randomly divided into normal + 5 °C group and normal + RT group, after 8 weeks of normal diet. Each group of mice were intervened for 2 h at different temperatures in the same time period for 8 weeks. Parameters, including body weight, food intake, inguinal white adipose tissue (iWAT) mass, brown adipose tissue (BAT) mass, blood glucose, blood lipids, leptin, adiponectin, adipose tissue pathology and in situ expression of uncoupling protein 1(UCP1) and prohibitin protein (PHB) in iWAT and BAT. Results: Compared with HFD + RT group, cold exposure not only significantly reduced body weight, blood glucose, iWAT weight/body weight ratio, TC, TG, LDL-C and leptin, but also increased food intake and BAT weight in high-fat diet mice. HE staining showed that iWAT and BAT cells became smaller and had multiple compartments. The iWAT had a browning trend. Immunohistochemistry showed that UCP1 and PHB protein in iWAT and BAT significantly increased. Conclusions: Cold exposure can counteract the weight gain caused by a high-fat diet, which may be related to the activation of brown adipose tissue and the induction of browning of white adipose tissues, increasing heat production and reducing white fat accumulation.

Dihydromyricetin promoted browning of subscapular adipose tissues in obese mice fed with high-fat diet via activating AMPK-PGC1 a-Sirtl signaling pathway / 中国药理学通报

Aim To observe the effect of dihydromyricetin (DHM) on the browning of subscapular adipose tissues in the high-fat diet fed obese mice, and clarify the mechanism. Methods C57BL/6J mice were fed with normal and high-fat diet, and were treated with or without low dose (125 mg • kg"1 • d"1) or high dose (250 mg • kg"1 • d"1) DHM for 16W. The body mass of mice was measured every four weeks during the experiment. After 16 weeks, the mice were fasted overnight. Blood samples were taken for fasting blood glucose. The mice were then sacrificed and the body length measured. The Lee' s index was calculated. The size of the subscapular adipocytes was observed by HE staining. The mRNA and protein expression of uncoupling protein 1 (UCP1) , PR domain containing 16 (Prdml6) , adenylate-activated protein kinase (AMPK) , peroxisome proliferator-activated receptor gamma-assisted activator alpha (PGCla) and silencing signal regulator 1 (Sirtl) were assessed by real time quantitative PCR and Western blot assay. Results Compared with normal control group (ND group) , the body mass of mice in high-fat diet group (HFD group) significantly increased, suggesting that the obese mice model was successfully replicated. In addition , blood glucose, Lee' s index and the fat cell diameter of the subscapular adipose tissues in HFD group all significantly increased, while the mRNA and pro-tein expression of UCP1, Prdml6, AMPK, PGCla and Sirtl significantly decreased. DHM markedly re-versed the changes of the above indexes of HFD mice, but DHM did not significantly affect the above indexes of normal mice. Conclusions Dihydromyricetin promotes the browning of subscapular adipose tissues in mice fed with high-fat diet, which might be via activating AMPK-PGC1 a-Sirtl signaling pathway.

Supplementation of Fermented Barley Extracts with Lactobacillus Plantarum dy-1 Inhibits Obesity via a UCP1-dependent Mechanism / 生物医学与环境科学（英文）

OBJECTIVE@#We aimed to explore how fermented barley extracts with Lactobacillus plantarum dy-1 (LFBE) affected the browning in adipocytes and obese rats.@*METHODS@#In vitro, 3T3-L1 cells were induced by LFBE, raw barley extraction (RBE) and polyphenol compounds (PC) from LFBE to evaluate the adipocyte differentiation. In vivo, obese SD rats induced by high fat diet (HFD) were randomly divided into three groups treated with oral gavage: (a) normal control diet with distilled water, (b) HFD with distilled water, (c) HFD with 800 mg LFBE/kg body weight (bw).@*RESULTS@#In vitro, LFBE and the PC in the extraction significantly inhibited adipogenesis and potentiated browning of 3T3-L1 preadipocytes, rather than RBE. In vivo, we observed remarkable decreases in the body weight, serum lipid levels, white adipose tissue (WAT) weights and cell sizes of brown adipose tissues (BAT) in the LFBE group after 10 weeks. LFBE group could gain more mass of interscapular BAT (IBAT) and promote the dehydrogenase activity in the mitochondria. And LFBE may potentiate process of the IBAT thermogenesis and epididymis adipose tissue (EAT) browning via activating the uncoupling protein 1 (UCP1)-dependent mechanism to suppress the obesity.@*CONCLUSION@#These results demonstrated that LFBE decreased obesity partly by increasing the BAT mass and the energy expenditure by activating BAT thermogenesis and WAT browning in a UCP1-dependent mechanism.

Cordycepin promotes browning of white adipose tissue through an AMP-activated protein kinase (AMPK)-dependent pathway

Obesity is a worldwide epidemic. Promoting browning of white adipose tissue (WAT) contributes to increased energy expenditure and hence counteracts obesity. Here we show that cordycepin (Cpn), a natural derivative of adenosine, increases energy expenditure, inhibits weight gain, improves metabolic profile and glucose tolerance, decreases WAT mass and adipocyte size, and enhances cold tolerance in normal and high-fat diet-fed mice. Cpn markedly increases the surface temperature around the inguinal WAT and turns the inguinal fat browner. Further investigations show that Cpn induces the development of brown-like adipocytes in inguinal and, to a less degree, epididymal WAT depots. Cpn also increases the expression of uncoupling protein 1 (UCP1) and other thermogenic genes in WAT and 3T3-L1 differentiated adipocytes, in which AMP-activated protein kinase (AMPK) plays an important role. Our results provide novel insights into the function of Cpn in regulating energy balance, and suggest a potential utility of Cpn in the treatment of obesity.

Role of ad36 in inducing browning of 3T3-L1 cells / 中华内分泌代谢杂志

Objective To investigate the role of adenovirus type 36 ( Ad36) in the browning of 3T3-L1 cells. Methods BODIPY staining was performed on the 0, 2nd, 4th, 6th and 8th days of the cocktail induction (control) group and the cocktail plus Ad36 induction ( experimental) group to observe the adipogenesis of 3T3-L1 cells. The mRNA and protein expressions of uncoupling protein-1 ( Ucp1 ), ATP synthase, H+ transporting, mitochondrial F1 complex, O subunit ( Atp5o), cytochrome c oxidase subunit 5B ( Cox5b), and perilipin were detected by real-time PCR and Western-blot. Results The results of BODIPY staining showed that the lipid droplets in the control group gradually became larger with the differentiation of the cells, while the lipid droplets in the experimental group firstly became larger, and then appeared smaller after Ad36 was added on the fourth day. Compared with the control group, the mRNA and protein expression levels of Ucp1, Atp5o, and Cox5b in the experimental group were significantly increased while the expression level of perilipin was significantly decreased ( all P＜0. 05 ). Conclusion During the differentiation of 3T3-L1 cells, Ad36 promotes its browning via increasing the expressions of Ucp1, Atp5o, and Cox5b.

The dark side of browning

The induction of brown-like adipocyte development in white adipose tissue (WAT) confers numerous metabolic benefits by decreasing adiposity and increasing energy expenditure. Therefore, WAT browning has gained considerable attention for its potential to reverse obesity and its associated co-morbidities. However, this perspective has been tainted by recent studies identifying the detrimental effects of inducing WAT browning. This review aims to highlight the adverse outcomes of both overactive and underactive browning activity, the harmful side effects of browning agents, as well as the molecular brake-switch system that has been proposed to regulate this process. Developing novel strategies that both sustain the metabolic improvements of WAT browning and attenuate the related adverse side effects is therefore essential for unlocking the therapeutic potential of browning agents in the treatment of metabolic diseases.