Overexpression of Krüppel like factor 2 (Klf2) or Klf7 inhibits adipocyte formation. However, it remains unclear whether Klf2 regulates klf7 expression in adipose tissue. In this study, oil red O staining and Western blotting were employed to study the effect of Klf2 overexpression on the differentiation of chicken preadipocytes. The results showed that Klf2 overexpression inhibited the differentiation of chicken preadipocytes induced by oleate and the expression of pparγ, while promoted klf7 expression in chicken preadipocytes. Spearman correlation analysis was used to study the correlation between the expression data of klf2 and klf7 in the adipose tissue of both human and chicken. The results showed that there was a significantly positive correlation between the expression of klf2 and klf7 in adipose tissues (r > 0.1). Luciferase reporter assay showed that overexpression of Klf2 significantly promoted the activity of chicken klf7 promoter (-241/-91, -521/-91, -1 845/-91, -2 286/-91, -1 215/-91; P < 0.05). In addition, the activity of klf7 promoter (-241/-91) reporter in chicken preadipocytes was significantly positively correlated with the amount of klf2 overexpression plasmid transfected (T_au=0.917 66, P=1.074×10^-7). Moreover, Klf2 overexpression significantly promoted the mRNA expression of klf7 in chicken preadipocytes (P < 0.05). In conclusion, upregulation of klf7 expression might be one of the pathways that Klf2 inhibits chicken adipocyte differentiation, and the sequence from -241 bp to -91 bp upstream chicken klf7 translation start site might mediate the regulation of Klf2 on klf7 transcription.
Animals ; Humans ; Chickens/genetics* ; Kruppel-Like Transcription Factors/metabolism* ; Transcription Factors/metabolism* ; Adipocytes/metabolism* ; Adipose Tissue/metabolism*

The aim of the present study was to investigate the effects of short-term ketogenic diet on the low temperature tolerance of mice and the involvement of peroxisome proliferator-activated receptor α (PPARα). C57BL/6J mice were divided into two groups: normal diet (WT+ND) group and ketogenic diet (WT+KD) group. After being fed with normal or ketogenic diet at room temperature for 2 d, the mice were exposed to 4 °C low temperature for 12 h. The changes in core temperature, blood glucose, blood pressure of mice under low temperature condition were detected, and the protein expression levels of PPARα and mitochondrial uncoupling protein 1 (UCP1) were detected by Western blot. PPARα knockout mice were divided into normal diet (PPARα^-/-+ND) group and ketogenic diet (PPARα^-/-+KD) group. After being fed with the normal or ketogenic diet at room temperature for 2 d, the mice were exposed to 4 °C low temperature for 12 h. The above indicators were also detected. The results showed that, at room temperature, the protein expression levels of PPARα and UCP1 in liver and brown adipose tissue of WT+KD group were significantly up-regulated, compared with those of WT+ND group. Under low temperature condition, compared with WT+ND, the core temperature and blood glucose of WT+KD group were increased, while mean arterial pressure was decreased; The ketogenic diet up-regulated PPARα protein expression in brown adipose tissue, as well as UCP1 protein expression in liver and brown adipose tissue of WT+KD group. Under low temperature condition, compared to WT+ND group, PPARα^-/-+ND group exhibited decreased core temperature and down-regulated PPARα and UCP1 protein expression levels in liver, skeletal muscle, white and brown adipose tissue. Compared to the PPARα^-/-+ND group, the PPARα^-/-+KD group exhibited decreased core temperature and did not show any difference in the protein expression of UCP1 in liver, skeletal muscle, white and brown adipose tissue. These results suggest that the ketogenic diet promotes UCP1 expression by up-regulating PPARα, thus improving low temperature tolerance of mice. Therefore, short-term ketogenic diet can be used as a potential intervention to improve the low temperature tolerance.
Animals ; Mice ; Adipose Tissue, Brown/metabolism* ; PPAR alpha/pharmacology* ; Diet, Ketogenic ; Uncoupling Protein 1/metabolism* ; Blood Glucose/metabolism* ; Temperature ; Mice, Inbred C57BL ; Liver ; Adipose Tissue/metabolism*

Atherosclerosis is a chronic inflammatory disease of vascular walls with a complex etiology. In recent years, the incidence of atherosclerosis continues to increase with obesity and diabetes as major risk factors. As an important metabolic organ in the body, adipose tissue also has a powerful endocrine function. In the case of obesity and diabetes, various cytokines and exosomes derived from adipose tissue mediate organ-organ/cell-cell crosstalk, and are involved in the occurrence and development of various diseases. As an important intercellular communicator, exosomes regulate the pathological process of various cardiovascular diseases and are closely related to atherosclerosis. In this paper, we reviewed the mechanism of adipose-derived exosomes in atherosclerosis with focus on endothelial dysfunction, inflammatory response, lipid metabolism disorder and insulin resistance, hoping to provide reference for the research, diagnosis and treatment of atherosclerosis.
Humans ; Exosomes/metabolism* ; Atherosclerosis ; Obesity/complications* ; Adipose Tissue/metabolism* ; Insulin Resistance

Skeletal muscle is one of the most important organs in animal, and the regulatory mechanism of skeletal muscle development is of great importance for the diagnosis of muscle-related diseases and the improvement of meat quality of livestock. The regulation of skeletal muscle development is a complex process, which is regulated by a large number of muscle secretory factors and signaling pathways. In addition, in order to maintain steady-state and maximum use of energy metabolism in the body, the body coordinates multiple tissues and organs to form the complex and sophisticated metabolic regulation network, which plays an important role for the regulation of skeletal muscle development. With the development of omics technologies, the underlying mechanism of tissue and organ communication has been deeply studied. This paper reviews the effects of crosstalk among adipose tissue, nerve tissue and intestinal tissue on skeletal muscle development, with the aim to provide a theoretical basis for targeted regulation of skeletal muscle development.
Animals ; Muscle, Skeletal/metabolism* ; Adipose Tissue/metabolism* ; Signal Transduction

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.
Mice ; Animals ; Adipose Tissue, Brown ; Sirtuin 1/pharmacology* ; Diabetes Mellitus, Type 2/metabolism* ; AMP-Activated Protein Kinases/metabolism* ; Morus/metabolism* ; Flavonoids/metabolism* ; Prospective Studies ; Signal Transduction ; Adipose Tissue, White ; Plant Leaves ; Uncoupling Protein 1/metabolism* ; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/metabolism*

OBJECTIVES: To observe the effects on the glucose-lipid metabolism and the expression of zinc-α2-glycoprotein (ZAG) and glucose transporter 4 (GLUT4) in the femoral quadriceps and adipose tissue after electroacupuncture (EA) at "Pishu" (BL 20), "Weiwanxiashu" (EX-B 3), "Zusanli" (ST 36) and "Sanyinjiao" (SP 6) in the rats with diabetes mellitus type 2 (T2DM), so as to explore the effect mechanism of EA in treatment of T2DM. METHODS: Twelve ZDF male rats were fed with high-sugar and high-fat fodder, Purina #5008 for 4 weeks to induce T2DM model. After successfully modeled, the rats were randomly divided into a model group and an EA group, with 6 rats in each one. Additionally, 6 ZL male rats of the same months age were collected as the blank group. The rats in the EA group were treated with EA at bilateral "Pishu" (BL 20), "Weiwanxiashu" (EX-B 3), "Zusanli" (ST 36) and "Sanyinjiao" (SP 6), with continuous wave, 15 Hz in frequency, and 2 mA in intensity. The electric stimulation lasted 20 min each time. EA was delivered once daily, 6 times a week for 4 weeks. Separately, the levels of fasting blood glucose (FBG) was measured before modeling, before and after intervention, and the body mass of each rat was weighted before and after intervention. After intervention, the levels of the total cholesterol (TC), triacylglycerol (TG) and free fatty acid (FFA) in serum were detected using enzyme colorimetric method; and the levels of the serum insulin (INS) and ZAG were detected by ELISA. Besides, the insulin sensitivity index (HOMA-ISI) was calculated. With Western blot technique adopted, the protein expressions of ZAG and GLUT4 in the femoral quadriceps and adipose tissue were determined. RESULTS: After intervention, compared with the blank group, the levels of FBG and body mass, and the levels of serum TC, TG, FFA and INS increased (P<0.01), while HOMA-ISI decreased (P<0.01); the level of ZAG in the serum and the protein expressions of ZAG and GLUT4 in the femoral quadriceps and adipose tissue dropped (P<0.01) in the model group. In the EA group, compared with the model group, the levels of FBG and body mass, and the levels of serum TC, TG, FFA and INS were reduced (P<0.01), and HOMA-ISI increased (P<0.01); the level of ZAG in the serum and the protein expressions of ZAG and GLUT4 in the femoral quadriceps and adipose tissue increased (P<0.01, P<0.05). CONCLUSIONS Electroacupuncture can effectively regulate glucose-lipid metabolism, improve insulin resistance and sensitivity in the rats with T2DM, which is associated with the modulation of ZAG and GLUT4 expression in the skeletal muscle and adipose tissue.
Rats ; Male ; Animals ; Glucose/metabolism* ; Electroacupuncture ; Rats, Sprague-Dawley ; Diabetes Mellitus, Type 2/therapy* ; Lipid Metabolism ; Triglycerides ; Adipose Tissue/metabolism* ; Acupuncture Points

The growth, differentiation and proliferation of adipose cells run through the whole life process. Dysregulation of lipid metabolism in adipose cells affects adipose tissue immunity and systemic energy metabolism. Increasingly available data suggest that lipid metabolism is involved in regulating the occurrence and development of various diseases, such as hyperlipidemia, nonalcoholic fatty liver disease, diabetes and cancer, which pose a major threat to human and animal health. Hypoxia inducible factor (HIF) is a major transcription factor mediating oxygen receptors in tissues and organs. HIF can induce disease by regulating lipid synthesis, fatty acid metabolism and lipid droplet formation. However, due to the difference of hypoxia degree, time and mode of action, there is no conclusive conclusion whether it has harmful or beneficial effects on the development of adipocytes and lipid metabolism. This article summarizes the regulation of hypoxia stress mediated transcription regulators and regulation of adipocyte development and lipid metabolism, aiming to reveal the potential mechanism of hypoxia induced changes in adipocyte metabolism pathways.
Animals ; Humans ; Lipid Metabolism ; Adipocytes/metabolism* ; Adipose Tissue/metabolism* ; Hypoxia/metabolism* ; Transcription Factors/metabolism*

This study investigated the mechanism of Zexie Decoction(ZXD) in promoting white adipose tissue browning/brown adipose tissue activation based on the GLP-1R/cAMP/PKA/CREB pathway. A hyperlipidemia model was induced by a western diet(WD) in mice, and the mice were divided into a control group, a model group(WD), and low-, medium-, and high-dose ZXD groups. An adipogenesis model was induced in 3T3-L1 cells in vitro, and with forskolin(FSK) used as a positive control, low-, medium-, and high-dose ZXD groups were set up. Immunohistochemistry and immunofluorescence results showed that compared with the WD group, ZXD promoted the expression of UCP1 in white and brown adipose tissues, and also upregulated UCP1, CPT1β, PPARα, and other genes in the cells. Western blot analysis showed a dose-dependent increase in the protein expression of PGC-1α, UCP1, and PPARα with ZXD treatment, indicating that ZXD could promote the white adipose tissue browning/brown adipose tissue activation. Hematoxylin-eosin(HE) staining results showed that after ZXD treatment, white and brown adipocytes were significantly reduced in size, and the mRNA expression of ATGL, HSL, MGL, and PLIN1 was significantly upregulated as compared with the results in the WD group. Oil red O staining and biochemical assays indicated that ZXD improved lipid accumulation and promoted lipolysis. Immunohistochemistry and immunofluorescence staining for p-CREB revealed that ZXD reversed the decreased expression of p-CREB caused by WD. In vitro intervention with ZXD increased the protein expression of CREB, p-CREB, and p-PKA substrate, and increased the mRNA level of CREB. ELISA detected an increase in intracellular cAMP concentration with ZXD treatment. Molecular docking analysis showed that multiple active components in Alismatis Rhizoma and Atractylodis Macrocephalae Rhizoma could form stable hydrogen bond interactions with GLP-1R. In conclusion, ZXD promotes white adipose tissue browning/brown adipose tissue activation both in vivo and in vitro, and its mechanism of action may be related to the GLP-1R/cAMP/PKA/CREB pathway.
Mice ; Animals ; Adipose Tissue, Brown ; Molecular Docking Simulation ; PPAR alpha/metabolism* ; Adipose Tissue, White ; RNA, Messenger/metabolism*

Human adipose-derived stem cells (hASCs) are a promising cell type for bone tissue regeneration. Circular RNAs (circRNAs) have been shown to play a critical role in regulating various cell differentiation and involve in mesenchymal stem cell osteogenesis. However, how circRNAs regulate hASCs in osteogenesis is still unclear. Herein, we found circ_0003204 was significantly downregulated during osteogenic differentiation of hASCs. Knockdown of circ_0003204 by siRNA or overexpression by lentivirus confirmed circ_0003204 could negatively regulate the osteogenic differentiation of hASCs. We performed dual-luciferase reporting assay and rescue experiments to verify circ_0003204 regulated osteogenic differentiation via sponging miR-370-3p. We predicted and confirmed that miR-370-3p had targets in the 3'-UTR of HDAC4 mRNA. The following rescue experiments indicated that circ_0003204 regulated the osteogenic differentiation of hASCs via miR-370-3p/HDAC4 axis. Subsequent in vivo experiments showed the silencing of circ_0003204 increased the bone formation and promoted the expression of osteogenic-related proteins in a mouse bone defect model, while overexpression of circ_0003204 inhibited bone defect repair. Our findings indicated that circ_0003204 might be a promising target to promote the efficacy of hASCs in repairing bone defects.
Adipose Tissue/metabolism* ; Animals ; Cell Differentiation/genetics* ; Cells, Cultured ; Histone Deacetylases/metabolism* ; Humans ; Mice ; MicroRNAs/metabolism* ; Osteogenesis/genetics* ; RNA, Circular/metabolism* ; Repressor Proteins/metabolism* ; Signal Transduction ; Stem Cells/metabolism*

This study explored the molecular mechanism underlying the Gegen Qinlian Decoction(GQD) promoting the differentiation of brown adipose tissue(BAT) to improve glucose and lipid metabolism disorders in diabetic rats. After the hypoglycemic effect of GQD on diabetic rats induced by high-fat diet combined with a low dose of streptozotocin was confirmed, the total RNA of rat BAT around scapula was extracted. Nuclear transcription genes Prdm16, Pparγc1α, Pparα, Pparγ and Sirt1, BAT marker genes Ucp1, Cidea and Dio2, energy expenditure gene Ampkα2 as well as BAT secretion factors Adpn, Fndc5, Angptl8, IL-6 and Rbp4 were detected by qPCR, then were analyzed by IPA software. Afterward, the total protein from rat BAT was extracted, and PRDM16, PGC1α, PPARγ, PPARα, SIRT1, ChREBP, AMPKα, UCP1, ADPN, NRG4, GLUT1 and GLUT4 were detected by Western blot. The mRNA expression levels of Pparγc1α, Pparα, Pparγ, Ucp1, Cidea, Ampkα2, Dio2, Fndc5, Rbp4 and Angptl8 were significantly increased(P<0.05) and those of Adpn and IL-6 were significantly decreased(P<0.05) in the GQD group compared with the diabetic group. In addition, Sirt1 showed a downward trend(P=0.104), whereas Prdm16 tended to be up-regulated(P=0.182) in the GQD group. IPA canonical pathway analysis and diseases-and-functions analysis suggested that GQD activated PPARα/RXRα and SIRT1 signaling pathways to promote the differentiation of BAT and reduce the excessive lipid accumulation. Moreover, the protein expression levels of PRDM16, PGC1α, PPARα, PPARγ, SIRT1, ChREBP, AMPKα, UCP1, GLUT1, GLUT4 and NRG4 were significantly decreased in the diabetic group(P<0.01), which were elevated after GQD intervention(P<0.05). Unexpectedly, the expression of ADPN protein in the diabetic group was up-regulated(P<0.01) as compared with the control group, which was down-regulated after the administration with GQD(P<0.01). This study indicated that GQD promoted BAT differentiation and maturity to increase energy consumption, which reduced the glucose and lipid metabolism disorders and thereby improved diabetes symptoms.
Adipose Tissue, Brown ; Animals ; Diabetes Mellitus, Experimental/genetics* ; Drugs, Chinese Herbal ; Fibronectins ; Glucose ; Lipid Metabolism ; Lipid Metabolism Disorders ; Rats