Adiponectin receptor 1 (AdipoR1) and Adiponectin receptor 2 (AdipoR2) can bind to adiponectin (AdipoQ) secreted by adipose tissue to participate in various physiological functions of the body. In order to explore the role of AdipoR1 and AdipoR2 in amphibians infected by Aeromonas hydrophila (Ah), the genes adipor1 and adipor2 of Rana dybowskii were cloned by reverse transcription-polymerase chain reaction (RT-PCR) and analyzed by bioinformatics. The tissue expression difference of adipor1 and adipor2 was analyzed by real-time fluorescence quantitative polymerase chain reaction (qRT-PCR), and an inflammatory model of R. dybowskii infected by Ah was constructed. The histopathological changes were observed by hematoxylin-eosin staining (HE staining); the expression profiles of adipor1 and adipor2 after infection were dynamically detected by qRT-PCR and Western blotting. The results show that AdipoR1 and AdipoR2 are cell membrane proteins with seven transmembrane domains. Phylogenetic tree also shows that AdipoR1 and AdipoR2 cluster with the amphibians in the same branch. qRT-PCR and Western blotting results show that adipor1 and adipor2 were up-regulated at different levels of transcription and translation upon Ah infection, but the response time and level were different. It is speculated that AdipoR1 and AdipoR2 participate in the process of bacterial immune response, providing a basis for further exploring the biological functions of AdipoR1 and AdipoR2 in amphibians.
Animals ; Receptors, Adiponectin/metabolism* ; Phylogeny ; Adiponectin/metabolism* ; Cloning, Molecular ; Ranidae/genetics*

OBJECTIVETo investigate the effects of GW4064, a farnesoid X receptor (FXR) agonist, on adiponectin and its receptors during the differentiation of 3T3-L1 preadipocytes and on adiponectin receptors in HepG2 cells.

METHODSThe mRNA expressions of FXR, PPARγ2, adiponectin, AdipoR1, and AdipoR2 and the protein levels of adiponectin on days 0, 2, 4, 6, and 8 during the differentiation of 3T3-L1 preadipocytes treated with GW4064 were detected by fluorescent real-time PCR and ELISA, respectively. The mRNA expressions of AdipoR1 and AdipoR2 in HepG2 cells were also examined at 0, 12, 24, and 48 h after GW4064 treatment.

RESULTSThe mRNA expressions of FXR, PPARγ2, adiponectin, and AdipoR2 in 3T3-L1 preadipocytes and AdipoR2 in HepG2 cells treated with GW4064 was significantly increased compared with the control group (all P<0.05). The protein level of adiponectin was also significantly increased after GW4064 treatment. The expression of AdipoR1 in either 3T3-L1 preadipocytes or HepG2 cells showed no significant changes after GW4064 treatment.

CONCLUSIONGW4064 can up-regulate the expressions of FXR, PPARγ2, adiponectin, AdipoR2 in 3T3-L1 preadipocytes and AdipoR2 in HepG2 cells. As adiponectin and its receptors are two important factors in the treatment of non-alcoholic fatty liver disease, FXR agonist may potentially produce therapeutic effect on non-alcoholic fatty liver disease and can regulate adipocytes via up-regulating PPARγ during adipocyte differentiation.

3T3-L1 Cells ; Adiponectin ; metabolism ; Animals ; Cell Differentiation ; drug effects ; Hep G2 Cells ; Humans ; Isoxazoles ; pharmacology ; Mice ; PPAR gamma ; metabolism ; Receptors, Adiponectin ; metabolism ; Receptors, Cytoplasmic and Nuclear ; agonists

OBJECTIVETo investigate the expression of adiponectin and its receptors (AdipoRs) in the retina of normal mice and mice with type 1 diabetes mellitus (T1DM).

METHODSC57BL/6 mice were randomly divided into control group and streptozotocin-induced T1DM group. Two months after the modeling, the total protein and adiponectin protein expression in the retina and choroid were measured using BCA method and enzyme-linked immunosorbent assay, respectively. Quantitative RT-PCR was performed to detect the mRNA expressions of AdipoRs in the retina and choroid, and Western blotting was employed to examine the protein expressions of AdipoRs in the retina.

RESULTSAdiponectin and AdipoRs proteins were expressed in the retina and choroid in normal mice. The expressions of adiponectin and AdipoR1 were up-regulated in the retina of mice with T1DM while AdipoR2 expression exhibited no significant changes.

CONCLUSIONAdiponectin and AdipoR1 may play an important role in the evolvement of type 1 diabetic retinopathy.

Adiponectin ; metabolism ; Animals ; Diabetes Mellitus, Experimental ; metabolism ; Diabetes Mellitus, Type 1 ; metabolism ; Diabetic Retinopathy ; metabolism ; pathology ; Male ; Mice ; Mice, Inbred C57BL ; Receptors, Adiponectin ; metabolism ; Retina ; metabolism

OBJECTIVETo explore the changes in the mRNA expression of adiponectin (Adp), adiponectin receptors(AdpR), and leptin in different adipose tissues of Wannanhua pigs at different stages of development, and their sexual dimorphism.

METHODSFive Wannanhua boars and five Wannanhua gilts were sampled at birth, 30, 45, 90, and 180 days of age respectively. The delta delta Ct relative quantification real-time PCR was used to detect the transcription levels of Adp, AdpR1, AdpR2, and leptin mRNAs in subcutaneous (SC) and perirenal (PR) adipose tissues, and beta-actin were used as internal standards.

RESULTSThe expression level of Adp, AdpR1, AdpR2, and leptin mRNA in SC and PR adipose tissue were changed with age significantly (P < 0.01). In general, Adp mRNA expression in SC adipose tissue was significantly lower than that in PR adipose tissue (P < 0.05), while AdpR1, AdpR2, and leptin mRNA expression in SC adipose tissue were significantly higher than those in PR adipose tissue (P < 0.05 or P < 0.01). Although the sexual dimorphism were found in apart genes or apart days of age, Adp, AdpR1, AdpR2, and leptin mRNA expression both in SC adipose tissue and PR adipose tissue had no significant differences between Wannanhua gilts and boars in general. Significant positive correlation was found between Adp and AdpR1, AdpR2 (P < 0.05 or P < 0.01), and significant negative correlation was found between Adp and leptin (P < 0.05) in SC adipose tissue and PR adipose tissue respectively (P < 0.05).

CONCLUSIONThe expression of Adp, AdpR1, AdpR2, and leptin mRNA in adipose tissue of Wannanhua pigs followed specific developmental patterns and tissue specificity. Adp correlated with its receptors.

Actins ; metabolism ; Adiponectin ; metabolism ; Adipose Tissue ; growth & development ; metabolism ; Animals ; Female ; Leptin ; metabolism ; Male ; RNA, Messenger ; genetics ; Receptors, Adiponectin ; metabolism ; Swine

OBJECTIVE: To investigate the effect of adiponectin on the osteoblast differentiation and its signal transduction. METHODS: Adipopnectin receptor (AdipoR) was detected by immunoblot analysis. Alkaline phosphatase (ALP) activity was measured by enzyme-linked immunosorbent assay. Osteocalcin was measured by a specific radioimmunoassay kit, and the extent of mineralized matrix was determined. RNA interference was used to down-regulate the expression of AdipoR1 in human osteoblasts, and the effect of adiponectin on osteoblast differentiation was investigated. RESULTS: Only AdipoR1 protein was detected in human osteoblasts. Adiponectin could promote osteoblast differentiation, and result in a dose-dependent increase in ALP activity, osteocalcin secretion, and an increase in mineralized nodules. Suppression of AdipoR1 with siRNA could abolish the adiponectin induced ALP expression. Adiponectin could induce the activation of p38 and JNK, but not ERK1/2 in osteoblasts, and the pretreatment of osteoblasts with the p38 inhibitor (SB203580) could block the adiponectin-induced ALP activity. CONCLUSION Adiponectin can induce human osteoblast differentiation via AdipoR1/p38 pathway.
Adiponectin ; pharmacology ; Alkaline Phosphatase ; metabolism ; Cell Differentiation ; drug effects ; Cells, Cultured ; Humans ; Osteoblasts ; cytology ; metabolism ; Osteocalcin ; analysis ; RNA, Small Interfering ; genetics ; Receptors, Adiponectin ; biosynthesis ; Signal Transduction

OBJECTIVES: Weight gain and glucose intolerance are the most common symptoms of metabolic syndrome. Certain patients complain of weight-change and hyperglycemia after receiving antidepressants. Our study evaluated the effects of antidepressants on serum glucose and energy metabolism. METHODS: Subjects were 32 Otsuka Long-Evans Tokushima Fatty (OLETF) and 35 wild-type Long-Evans Tokushima Otsuka (LETO) rats. From age 11 weeks, the rats were divided into 4 subgroups within each strain. We administered the designated antidepressant-amitriptyline, fluoxetine, or mirtazapine-to these subgroups, allocating the fourth as the control. After exactly 4 weeks' medication, we sacrificed the animals and checked their weight, glucose, insulin, leptin, adiponectin, and expression of adiponectin receptor mRNA. RESULTS: Fluoxetine subgroups in both strains gained the least weight. The glucose, triglyceride, and cholesterol levels of all OLETF antidepressant subgroups did not differ from the controls. Adiponectins in amitriptyline- and mirtazapine-subgroups were higher than control. All antidepressant subgroups showed elevated expressions of adiponectin receptor mRNA in fat, muscle, and the pancreas. CONCLUSION: Amitriptyline and mirtazapine seem to regulate adiponectin and expression of adiponectin receptor mRNA. Even though the underlying mechanisms were different, we conclude none of the antidepressants would have negative influences on energy metabolism in diabetogenic animals.
Adiponectin ; Amitriptyline ; Animals ; Antidepressive Agents ; Cholesterol ; Energy Metabolism ; Fluoxetine ; Glucose ; Glucose Intolerance ; Humans ; Hyperglycemia ; Insulin ; Leptin ; Mianserin ; Muscles ; Pancreas ; Rats ; Receptors, Adiponectin ; RNA, Messenger ; Sprains and Strains ; Weight Gain

BACKGROUNDThe synovial fluid concentrations of adiponectin are significantly higher in patients with rheumatoid arthritis (RA) than in patients with osteoarthritis (OA). Accumulating evidence suggests that adiponectin may be an inducer of inflammation in arthritis, but the mechanism remains unclear. The objectives of this study were to compare the expression levels of adiponectin receptors in rheumatoid arthritis synovial fibroblasts (RASF) and osteoarthritis synovial fibroblasts (OASF), evaluate the roles of adiponectin receptors in adiponectin-induced prostaglandin E(2) (PGE(2)) production, and then investigate the effects of a nonsteroidal anti-inflammatory drug (NSAID) and a cyclooxygenase (COX)-2-selective inhibitor on adiponectin-induced PGE(2) release.

METHODSThe expressions of adiponectin receptor 1 (AdipoR1) and AdipoR2 mRNA and protein in synovial fibroblasts from seven patients with RA and eight patients with OA undergoing total knee replacement were evaluated by real-time polymerase chain reaction, immunofluorescence microscopy and Western blotting analysis. Adiponectin-induced PGE(2) production was detected by enzyme-linked immunosorbent assay. RNA interference against the AdipoR1 and AdipoR2 genes was performed to investigate the effects of the adiponectin receptors on adiponectin-induced PGE(2) production in both RASF and OASF.

RESULTSAdipoR1 and AdipoR2 mRNA and protein were expressed by both RASF and OASF. Compared with OASF, RASF exhibited higher levels of AdipoR1, but there was no significant difference for AdipoR2. Adiponectin induced the production of PGE(2) by the synovial fibroblasts in a concentration-dependent manner, and this was more obvious in RASF. RNA interference showed that the difference may be mediated by the diverse distribution of AdipoR1. The adiponectin-induced PGE(2) production was efficiently relieved by the NSAID and COX-2-selective inhibitor.

CONCLUSIONThe present findings suggest that AdipoR1 may mediate the difference in adiponectin-induced PGE(2) production in RASF and OASF.

Adiponectin ; pharmacology ; Arthritis, Rheumatoid ; metabolism ; Blotting, Western ; Cells, Cultured ; Dinoprostone ; metabolism ; Female ; Fibroblasts ; drug effects ; metabolism ; Humans ; Immunoassay ; Male ; Microscopy, Fluorescence ; Middle Aged ; Osteoarthritis ; metabolism ; RNA, Small Interfering ; Real-Time Polymerase Chain Reaction ; Receptors, Adiponectin ; genetics ; metabolism ; Synovial Membrane ; cytology

OBJECTIVE: Depression and metabolic disorders have overlapping psychosocial and pathophysiological causes. Current research is focused on the possible role of adiponectin in regulating common biological mechanisms. Xiaoyao San (XYS), a classic Chinese medicine compound, has been widely used in the treatment of depression and can alleviate metabolic disorders such as lipid or glucose metabolism disorders. However, the ability of XYS to ameliorate depression-like behavior as well as metabolic dysfunction in mice and the underlying mechanisms are unclear. METHODS: An in vivo animal model of depression was established by chronic social defeat stress (CSDS). XYS and fluoxetine were administered by gavage to the drug intervention group. Depression-like behaviors were analyzed by the social interaction test, open field test, forced swim test, and elevated plus maze test. Glucose levels were measured using the oral glucose tolerance test. The involvement of certain molecules was validated by immunofluorescence, histopathology, and Western blotting. In vitro, hypothalamic primary neurons were exposed to high glucose to induce neuronal damage, and the neuroprotective effect of XYS was evaluated by cell counting kit-8 assay. Immunofluorescence and Western blotting were used to evaluate the influences of XYS on adiponectin receptor 1 (AdipoR1), adenosine 5'-monophosphate-activated protein kinase (AMPK), acetyl-coenzyme A carboxylase (ACC) and other related proteins. RESULTS: XYS ameliorated CSDS-induced depression-like behaviors and glucose tolerance impairment in mice and increased the level of serum adiponectin. XYS also restored Nissl bodies in hypothalamic neurons in mice that exhibited depression-like behaviors and decreased the degree of neuronal morphological damage. In vivo and in vitro studies indicated that XYS increased the expression of AdipoR1 in hypothalamic neurons. CONCLUSION Adiponectin may be a key regulator linking depression and metabolic disorders; regulation of the hypothalamic AdipoR1/AMPK/ACC pathway plays an important role in treatment of depression by XYS.
AMP-Activated Protein Kinases/metabolism* ; Acetyl-CoA Carboxylase/metabolism* ; Adiponectin/metabolism* ; Animals ; Antidepressive Agents/pharmacology* ; China ; Depression/drug therapy* ; Disease Models, Animal ; Drugs, Chinese Herbal/therapeutic use* ; Glucose ; Hypothalamus/metabolism* ; Mice ; Receptors, Adiponectin/metabolism*

To determine whether adiponectin may have synergistic effects in combination with the proinflammatory cytokine interleukin (IL)-1beta regarding the production of proinflammatory mediators during arthritic joint inflammation, synovial cells from rheumatoid arthritis (RA) patients were treated with adiponectin, IL-1beta, and their combination for 24 h. Culture supernatant was collected and analyzed by enzyme-linked immunosorbent assay for levels of IL-6, IL-8, prostaglandin E2 (PGE2), vascular endothelial growth factor (VEGF), and matrix metalloproteinases (MMPs). Adiponectin-mediated intracellular signaling pathways were investigated to elucidate the molecular mechanisms underlying their synergy. The association of proinflammatory mediators with adiponectin was investigated in the synovial fluid of arthritis patients. Adiponectin functioned synergistically with IL-1beta to activate IL-6, IL-8, and PGE2 expression in RA fibroblast-like synoviocytes; Levels of VEGF, MMP-1, and MMP-13 were not synergistically stimulated. Adiponectin and IL-1beta each increased the expression of both adiponectin receptor 1 and IL-1 receptor 1. However, adiponectin and IL-1beta did not synergistically support the degradation of IkappaB-alpha or the nuclear translocation of NF-kappaB. Synergistically increased gene expression was significantly inhibited by MG132, an NF-kappaB inhibitor. Supporting the in vitro results, IL-6 and IL-8 levels were positively associated with adiponectin in synovial joint fluid from patients with RA, but not osteoarthritis (OA). In conclusion, adiponectin and IL-1beta may synergistically stimulate the production of proinflammatory mediators through unknown signaling pathways during arthritic joint inflammation. Adiponectin may be more important to the pathogenesis of RA than previously thought.
Adiponectin/administration & dosage/*metabolism ; *Arthritis, Rheumatoid/metabolism/pathology ; Cells, Cultured ; Cyclooxygenase 2/metabolism ; Gene Expression Regulation/drug effects ; Humans ; *Inflammation/metabolism/pathology ; Interleukin-1beta/administration & dosage/*metabolism ; Interleukin-6/metabolism ; Interleukin-8/metabolism ; Joints/metabolism/pathology ; Matrix Metalloproteinases ; NF-kappa B/metabolism ; Obesity/metabolism/pathology ; Osteoarthritis ; Receptors, Adiponectin/metabolism ; Receptors, Interleukin-1/metabolism ; *Synovial Fluid/cytology/metabolism

For the regulation of energy balance in various internal organs including gut, pancreas and liver, visceral adipose tissue and brain perform important sensing and signaling roles via neural and endocrine pathway. Among these, adipose tissue has been known as a simple energy-storing organ, which stores excess energy in triglyceride. However, it became apparent that adipocytes have various receptors related to energy homeostasis, and secrete adipocytokines by endocrine, paracrine and autocrine mechanisms. In this review, basic roles of adipocytes in energy homeostasis and the correlation between adipocyte signals and digestive diseases are discussed.
Adipocytes/*metabolism ; Adipokines/*physiology ; Adiponectin/physiology ; Digestive System Diseases/*metabolism ; *Energy Metabolism ; Homeostasis ; Humans ; Leptin/physiology ; Peroxisome Proliferator-Activated Receptors/physiology ; Resistin/physiology ; Signal Transduction