Dietary n-3 and n-6 polyunsaturated fatty acids differentially modulate the adiponectin and leptinmediated major signaling pathways in visceral and subcutaneous white adipose tissue in high fat diet induced obesity in Wistar rats.

Obesity is a chronic metabolic disease that involves excessive accumulation of fat in white adipose tissue (WAT). Apart from storing excess fats, WAT also serves as an important endocrine organ secreting adipocytokines such as adiponectin and leptin. Adiponectin and leptin bind to their transmembrane receptors adiponectin receptor 1 (AdipoR1)/adiponectin receptor 2 (AdipoR2) and Ob-R, respectively, and mediate their effect on metabolism by regulating multiple downstream targets. Dietary fat is considered the main culprit behind obesity development. Numerous preclinical studies have highlighted role of essential polyunsaturated fatty acids (PUFAs), particularly n-3 PUFAs, in prevention of obesity. Despite emerging data, there still is no clear understanding of the mechanism of action of n-3 PUFAs and n-6 PUFAs on adipose tissue function in two functionally and anatomically different depots of WAT: visceral and subcutaneous. We designed this study using a high fat diet (HFD) fed rodent model of obesity to test our hypothesis that n-3 and n-6 PUFAs possibly differentially modulate adipokine secretion and downstream metabolic pathways such as peroxisome proliferator-activated receptor-γ (PPAR-γ), protein kinase B (AKT)-forkhead box O1 (FOXO1), and Janus kinase-signal transducer and activator of transcription in obesity. The results of the current study showed that n-3 PUFAs upregulate the expression of AdipoR1/R2 and ameliorate the effects of HFD by modulating adipogenesis via PPAR-γ and by improving glucose tolerance and lipid metabolism via AKT-FOXO1 axis in fish oil fed rats. However, n-6 PUFAs did not show any remarkable change compared with HFD fed animals. Our study highlights that n-3 PUFAs modulate expression of various targets in adiponectin and leptin signaling cascade, bringing about an overall reduction in obesity and improvement in adipose tissue function in HFD induced obesity.

Atractylodes lancea and Magnolia officinalis combination protects against high fructose-impaired insulin signaling in glomerular podocytes through upregulating Sirt1 to inhibit p53-driven miR-221.

ETHNOPHARMACOLOGICAL RELEVANCE: In traditional Chinese medicine, a long term of improper diet causes the Dampness and disturbs Zang-Fu's functions including Kidney deficiency. Atractylodes lancea (Atr) and Magnolia officinalis (Mag) as a famous herb pair are commonly used to transform Dampness, with kidney protection. AIM OF THE STUDY: To explore how Atr and Mag protected against insulin signaling impairment in glomerular podocytes induced by high dietary fructose feeding, a major contributor for insulin resistance in glomerular podocyte dysfunction. MATERIALS AND METHODS: Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analyze constituents of Atr and Mag. Rat model was induced by 10% fructose drinking water in vivo, and heat-sensitive human podocyte cells (HPCs) were exposed to 5 mM fructose in vitro. Animal or cultured podocyte models were treated with different doses of Atr, Mag or Atr and Mag combination. Western blot, qRT-PCR and immunofluorescence assays as well as other experiments were performed to detect adiponectin receptor protein 1 (AdipoR1), protein kinase B (AKT), Sirt1, p53 and miR-221 levels in rat glomeruli or HPCs, respectively. RESULTS: Fifty-five components were identified in Atr and Mag combination. Network pharmacology analysis indicated that Atr and Mag combination might affect insulin signaling pathway. This combination significantly improved systemic insulin resistance and prevented glomerulus morphological damage in high fructose-fed rats. Of note, high fructose decreased IRS1, AKT and AdipoR1 in rat glomeruli and cultured podocytes. Further data from cultured podocytes with Sirt1 inhibitor/agonist, p53 agonist/inhibitor, or miR-221 mimic/inhibitor showed that high fructose downregulated Sirt1 to stimulate p53-driven miR-221, resulting in insulin signaling impairment. Atr and Mag combination effectively increased Sirt1, and decreased p53 and miR-221 in in vivo and in vitro models. CONCLUSIONS: Atr and Mag combination improved insulin signaling in high fructose-stimulated glomerular podocytes possibly through upregulating Sirt1 to inhibit p53-driven miR-221. Thus, the regulation of Sirt1/p53/miR-221 by this combination may be a potential therapeutic approach in podocyte insulin signaling impairment.

Xiaoyao San, a Chinese herbal formula, ameliorates depression-like behavior in mice through the AdipoR1/AMPK/ACC pathway in hypothalamus.

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.

Polyphenolic-rich Cissus quadrangularis extract ameliorates insulin resistance by activating AdipoR1 in peri-/post-menopausal rats.

Insulin resistance (IR) is a significant complication in menopausal women, which predisposes them to cardiovascular disorder, obesity, and diabetes. Cissus quadrangularis is a polyphenolic plant rich in nutrients and is used as an edible vegetable in Nigeria. Previously, we investigated that C. quadrangularis extract (EECQ) treatment ameliorates IR, hyperlipidemia, and overweight in diabetic rats. Accordingly, in the current study, we further evaluated the adiponectin mimetic activity of EECQ in peri-/post-menopausal rats. Perimenopause was induced by High-fat diet/4-vinylcyclohexenediepoxide/(HFD-VCD), while postmenopause was by HFD/bilateral ovariectomy (HFD-OVX). Both the menopausal rats demonstrated an abnormal level of sex hormones, IR, hyperlipidemia, increased fat mass, and abnormal weight gain. Nevertheless, EECQ treated group revealed protection from these untoward complications. Furthermore, the docking score of major constituents of EECQ on adiponectin receptor 1 (AdipoR1) depicted a strong binding affinity, which was comparable to the ligand adipoRon. Besides, AdipoR1 expression determined by RT-PCR, Western blotting, and immunohistochemistry was downregulated in peri-/post-menopausal rats. Similarly, the expression of AdipoR1 downstream marker APPL1 and insulin sensitivity markers, including IRS1, Akt1, and GLUT4, were also dysregulated in menopausal rats. However, EECQ treated rats manifested restoration of normal expression of APPL1, IRS1, Akt1, and GLUT4 by upregulating AdipoR1. Altogether, the current study promulgated the adiponectin mimetic activity of EECQ, which is substantial to mitigate IR in menopausal conditions.

Xiaoyao San, a Chinese herbal formula, ameliorates depression-like behavior in mice through the AdipoR1/AMPK/ACC pathway in hypothalamus / 中西医结合学报

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.

Tetrahydrocurcumin Upregulates the Adiponectin-AdipoR Pathway and Improves Insulin Signaling and Pancreatic ß-Cell Function in High-Fat Diet/Streptozotocin-Induced Diabetic Obese Mice.

Impairment of adiponectin production and function is closely associated with insulin resistance and type 2 diabetes, which are linked to obesity. Studies in animal models have documented the anti-diabetic effects of tetrahydrocurcumin (THC). Although several possible mechanisms have been proposed, the contribution of adiponectin signaling on THC-mediated antihyperglycemic effects remains unknown. Here, we report that adiposity, steatosis, and hyperglycemia were potently attenuated in high-fat diet/streptozotocin-induced diabetic obese mice after they received 20 and 100 mg/kg THC for 14 weeks. THC upregulated UCP-1 in adipose tissue and elevated adiponectin levels in the circulation. THC upregulated the AdipoR1/R2-APPL1-mediated pathway in the liver and skeletal muscle, which contributes to improved insulin signaling, glucose utilization, and lipid metabolism. Furthermore, THC treatment significantly (p < 0.05) preserved islet mass, reduced apoptosis, and restored defective insulin expression in the pancreatic ß-cells of diabetic obese mice, which was accompanied by an elevation of AdipoR1 and APPL1. These results demonstrated a potential mechanism underlying the beneficial effects of THC against hyperglycemia via the adiponectin-AdipoR pathway, and thus, may lead to a novel therapeutic use for type 2 diabetes.

Pectic Oligogalacturonide Facilitates the Synthesis and Activation of Adiponectin to Improve Hepatic Lipid Oxidation.

SCOPE: Adiponectin (ADPN), a kind of adipokines, plays an important role in the regulation of lipid metabolism. The objective of this study is focused on the ADPN to investigate the functional mechanisms of pectin oligosaccharide (POS) from hawthorn fruit in the improvement of hepatic fatty acid oxidation. METHOD AND RESULTS: High-fat fed mice are used in this experiment. POS is administrated with the doses of 0.25, 0.75, and 1.5 g kg-1 diet, respectively. The results demonstrate that gene and protein expressions of ADPN synthesis regulators involved in PKA/ERK/CREB and C/EBPα/PPARγ pathways are upregulated by POS administration. POS also activates the AdiopR1/AMPKα/PGC1 and AdipoR2/PPARα signaling pathways to improve the fatty acid oxidation in the liver, which is further accelerated by the enhancement of mitochondrial functions. CONCLUSION: POS can act as an ADPN activator to improve lipid metabolism, leading it to the applications of biomedical and functional foods for ameliorating chronic liver diseases resulted from a high-energy diet.

A flavonoid-rich Smilax china L. extract prevents obesity by upregulating the adiponectin-receptor/AMPK signalling pathway and modulating the gut microbiota in mice.

The aim of this study was to investigate the effects of Smilax china L. flavonoid (SCF) on obesity and changes in gut microbiota high-fat/high-sucrose (HFHS)-fed mice. Male C57BL/6 mice fed either a normal-chow (NC) or a HFHS diet were treated with SCF for 12 weeks. The effect of SCF on the composition of gut microbiota was assessed by 16S rDNA sequencing. SCFA levels in the caecum were quantified by GC-MS. SCF supplementation alleviated the body weight gain, fat accumulation, serum lipid parameters, and hepatic steatosis and improved glucose homeostasis. SCF significantly increased plasma adiponectin level, adiponectin-receptor-gene (AdipoR1 and AdipoR2) expression in the liver, activated AMPKα, downregulated the expression of SREBP1-c, FAS, and ACCα, and upregulated the expression of PPARα, CPT-1α, and UCP-1. The anti-obesity effects of SCF might be through upregulation of adiponectin-receptor/AMPK signalling to improve lipid metabolism. SCF reversed HFHS-induced dysbiosis of gut microbiota and decreased SCFA production in the caecum, thus reducing energy absorption and leading to loss of body weight. Spearman's correlation analysis revealed significant correlations between obesity phenotypes, SCFA levels, and changes in gut microbiota. The results showed that SCF may be an effective dietary supplement that is useful for suppressing the development of obesity and associated disorders.

Adiponectin receptor agonist AdipoRon ameliorates renal inflammation in diet-induced obese mice and endotoxin-treated human glomeruli ex vivo.

AIMS/HYPOTHESIS: Chronic low-grade inflammation with local upregulation of proinflammatory molecules plays a role in the progression of obesity-related renal injury. Reduced serum concentration of anti-inflammatory adiponectin may promote chronic inflammation. Here, we investigated the potential anti-inflammatory and renoprotective effects and mechanisms of action of AdipoRon, an adiponectin receptor agonist. METHODS: Wild-type DBA/2J mice were fed with high-fat diet (HFD) supplemented or not with AdipoRon to model obesity-induced metabolic endotoxaemia and chronic low-grade inflammation and we assessed changes in the glomerular morphology and expression of proinflammatory markers. We also treated human glomeruli ex vivo and human podocytes in vitro with AdipoRon and bacterial lipopolysaccharide (LPS), an endotoxin upregulated in obesity and diabetes, and analysed the secretion of inflammatory cytokines, activation of inflammatory signal transduction pathways, apoptosis and migration. RESULTS: In HFD-fed mice, AdipoRon attenuated renal inflammation, as demonstrated by reduced expression of glomerular activated NF-κB p65 subunit (NF-κB-p65) (70%, p < 0.001), TNFα (48%, p < 0.01), IL-1ß (51%, p < 0.001) and TGFß (46%, p < 0.001), renal IL-6 and IL-4 (21% and 20%, p < 0.05), and lowered glomerular F4/80-positive macrophage infiltration (31%, p < 0.001). In addition, AdipoRon ameliorated HFD-induced glomerular hypertrophy (12%, p < 0.001), fibronectin accumulation (50%, p < 0.01) and podocyte loss (12%, p < 0.001), and reduced podocyte foot process effacement (15%, p < 0.001) and thickening of the glomerular basement membrane (18%, p < 0.001). In cultured podocytes, AdipoRon attenuated the LPS-induced activation of the central inflammatory signalling pathways NF-κB-p65, c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38-MAPK) (30%, 36% and 22%, respectively, p < 0.001), reduced the secretion of TNFα (32%, p < 0.01), and protected against podocyte apoptosis and migration. In human glomeruli ex vivo, AdipoRon reduced the LPS-induced secretion of inflammatory cytokines IL-1ß, IL-18, IL-6 and IL-10. CONCLUSIONS/INTERPRETATION: AdipoRon attenuated the renal expression of proinflammatory cytokines in HFD-fed mice and LPS-stimulated human glomeruli, which apparently contributed to the amelioration of glomerular inflammation and injury. Mechanistically, based on assays on cultured podocytes, AdipoRon reduced LPS-induced activation of the NF-κB-p65, JNK and p38-MAPK pathways, thereby impelling the decrease in apoptosis, migration and secretion of TNFα. We conclude that the activation of the adiponectin receptor by AdipoRon is a potent strategy to attenuate endotoxaemia-associated renal inflammation.

Effects of carotid baroreceptor stimulation on aortic remodeling in obese rats.

BACKGROUND AND AIM: Our previous study found carotid baroreceptor stimulation (CBS) reduces body weight and white adipose tissue (WAT) weight, restores abnormal secretion of adipocytokines and inflammation factors, decreases systolic blood pressure (SBP) by inhibiting activation of sympathetic nervous system (SNS) and renin-angiotensin system (RAS) in obese rats. In this study, we explore effects of CBS on aortic remodeling in obese rats. METHODS AND RESULTS: Rats were fed high-fat diet (HFD) for 16 weeks to induce obesity and underwent either CBS device implantation and stimulation or sham operation at 8 weeks. BP and body weight were measured weekly. RAS activity of WAT, histological, biochemical and functional profiles of aortas were detected after 16 weeks. CBS effectively decreased BP in obese rats, downregulated mRNA expression of angiotensinogen (AGT) and renin in WAT, concentrations of AGT, renin, angiotensin II (Ang II), protein levels of Ang II receptor 1 (AT1R) and Ang II receptor 2 (AT2R) in WAT were declined. CBS inhibited reactive oxygen species (ROS) generation, inflammatory response and endoplasmic reticulum (ER) stress in aortas of obese rats, restrained vascular wall thickening and vascular smooth muscle cells (VSMCs) phenotypic switching, increased nitric oxide (NO) synthesis, promoted endothelium-dependent vasodilatation by decreasing protein expression of AT1R and leptin receptor (LepR), increasing protein expression of adiponectin receptor 1 (AdipoR1) in aortic VSMCs. CONCLUSION: CBS reduced BP and reversed aortic remodeling in obese rats, the underlying mechanism might be related to the suppressed SNS activity, restored adipocytokine secretion and restrained RAS activity of WAT.

Adiponectin-mimetic novel nonapeptide rescues aberrant neuronal metabolic-associated memory deficits in Alzheimer's disease.

BACKGROUND: Recently, we and other researchers reported that brain metabolic disorders are implicated in Alzheimer's disease (AD), a progressive, devastating and incurable neurodegenerative disease. Hence, novel therapeutic approaches are urgently needed to explore potential and novel therapeutic targets/agents for the treatment of AD. The neuronal adiponectin receptor 1 (AdipoR1) is an emerging potential target for intervention in metabolic-associated AD. We aimed to validate this hypothesis and explore in-depth the therapeutic effects of an osmotin-derived adiponectin-mimetic novel nonapeptide (Os-pep) on metabolic-associated AD. METHODS: We used an Os-pep dosage regimen (5 µg/g, i.p., on alternating days for 45 days) for APP/PS1 in amyloid ß oligomer-injected, transgenic adiponectin knockout (Adipo-/-) and AdipoR1 knockdown mice. After behavioral studies, brain tissues were subjected to biochemical and immunohistochemical analyses. In separate cohorts of mice, electrophysiolocal and Golgi staining experiments were performed. To validate the in vivo studies, we used human APP Swedish (swe)/Indiana (ind)-overexpressing neuroblastoma SH-SY5Y cells, which were subjected to knockdown of AdipoR1 and APMK with siRNAs, treated with Os-pep and other conditions as per the mechanistic approach, and we proceeded to perform further biochemical analyses. RESULTS: Our in vitro and in vivo results show that Os-pep has good safety and neuroprotection profiles and crosses the blood-brain barrier. We found reduced levels of neuronal AdipoR1 in human AD brain tissue. Os-pep stimulates AdipoR1 and its downstream target, AMP-activated protein kinase (AMPK) signaling, in AD and Adipo-/- mice. Mechanistically, in all of the in vivo and in vitro studies, Os-pep rescued aberrant neuronal metabolism by reducing neuronal insulin resistance and activated downstream insulin signaling through regulation of AdipoR1/AMPK signaling to consequently improve the memory functions of the AD and Adipo-/- mice, which was associated with improved synaptic function and long-term potentiation via an AdipoR1-dependent mechanism. CONCLUSION: Our findings show that Os-pep activates AdipoR1/AMPK signaling and regulates neuronal insulin resistance and insulin signaling, which subsequently rescues memory deficits in AD and adiponectin-deficient models. Taken together, the results indicate that Os-pep, as an adiponectin-mimetic novel nonapeptide, is a valuable and promising potential therapeutic candidate to treat aberrant brain metabolism associated with AD and other neurodegenerative diseases.

AdipoR agonist increases insulin sensitivity and exercise endurance in AdipoR-humanized mice.

Adiponectin receptors, AdipoR1 and AdipoR2 exert anti-diabetic effects. Although muscle-specific disruption of AdipoR1 has been shown to result in decreased insulin sensitivity and decreased exercise endurance, it remains to be determined whether upregulation of AdipoR1 could reverse them in obese diabetic mice. Here, we show that muscle-specific expression of human AdipoR1 increased expression levels of genes involved in mitochondrial biogenesis and oxidative stress-detoxification to almost the same extents as treadmill exercise, and concomitantly increased insulin sensitivity and exercise endurance in obese diabetic mice. Moreover, we created AdipoR-humanized mice which express human AdipoR1 in muscle of AdipoR1·R2 double-knockout mice. Most importantly, the small-molecule AdipoR agonist AdipoRon could exert its beneficial effects in muscle via human AdipoR, and increased insulin sensitivity and exercise endurance in AdipoR-humanized mice. This study suggests that expression of human AdipoR1 in skeletal muscle could be exercise-mimetics, and that AdipoRon could exert its beneficial effects via human AdipoR1.

Nobiletin alleviates high-fat diet-induced nonalcoholic fatty liver disease by modulating AdipoR1 and gp91phox expression in rats.

Nobiletin, one of the polymethoxylated flavonoids isolated from citrus peels, is reported to possess various biological activities. The current study investigates the effect and possible mechanisms of nobiletin on nonalcoholic fatty liver disease (NAFLD) in high-fat diet (HFD)-fed rats. Male Sprague-Dawley rats were administrated with HFD and fructose (15%) in drinking water for 16 weeks to induce NAFLD. HFD-fed rats were treated with nobiletin (20 or 40 mg/kg/day) or vehicle for the last 4 weeks. Treatment of HFD-fed rats with nobiletin significantly reduced systolic blood pressure, adiposity, hyperlipidemia, insulin resistance, hepatic lipids content, NAFLD activity score and liver fibrosis. Nobiletin significantly increased plasma adiponectin levels, together with up-regulation of liver adiponectin receptor 1 (AdipoR1) expression. Additionally, decreased malondialdehyde levels and increased superoxide dismutase activity in plasma and hepatic tissue, consistent with down-regulation of liver NADPH oxidase subunit gp91phox expression, were also observed after nobiletin treatment. Furthermore, high dose of nobiletin exhibited higher therapeutic effect as a compared to low dose. These findings suggest that nobiletin alleviates HFD-induced NAFLD and metabolic dysfunction in rats. There might be an association between the observed inhibitory effect of nobiletin on NAFLD and modulation of AdipoR1 and gp91phox.

Selective dietary polyphenols induce differentiation of human osteoblasts by adiponectin receptor 1-mediated reprogramming of mitochondrial energy metabolism.

Anabolic therapies for osteoporosis including dietary polyphenols promote osteoblast function by influencing its energy metabolism. Among the dietary polyphenols, the beneficial skeletal effects of genistein (an isoflavone), kaempferol (a flavone), resveratrol (RES, a stilbenoid) and epigallocatechin gallate (EGCG, a catechin) have been reported in preclinical studies. We studied the action mechanism of these nutraceuticals on osteoblast bioenergetics. All stimulated differentiation of human fetal osteoblasts (hFOB). However, only EGCG and RES stimulated mitochondrial parameters including basal and maximum respiration, spare respiratory capacity and ATP production (a measure of the activity of electron transport chain/ETC). Increases in these parameters were due to increased mitochondrial biogenesis and consequent upregulation of several mitochondrial proteins including those involved in ETC. Rotenone blocked the osteogenic effect of EGCG and RES suggesting the mediatory action of mitochondria. Both compounds rapidly activated AMPK, and dorsomorphin (an AMPK inhibitor) abolished ATP production stimulated by these compounds. Moreover, EGCG and RES upregulated the mitochondrial biogenesis factor, PGC-1α which is downstream of AMPK activation, and silencing PGC-1α blocked their stimulatory effects on ATP production and hFOB differentiation. Adiponectin receptor 1 (AdipoR1) is an upstream regulator of PGC-1α, and both compounds increased the expression of AdipoR1 but not AdipoR2. Silencing AdipoR1 blocked the upregulation of EGCG/RES-induced PGC-1α and hFOB differentiation. In rat calvarium, both compounds increased AdipoR1, PGC-1α, and RunX2 (the osteoblast transcription factor) with a concomitant increase in mitochondrial copy number and ATP levels. We conclude that EGCG and RES display osteogenic effects by reprogramming osteoblastic bioenergetics by acting as the AdipoR1 agonists.

The phytoestrogen, quercetin, in serum, uterus and ovary as a potential treatment for dehydroepiandrosterone-induced polycystic ovary syndrome in the rat.

The exact mechanisms of polycystic ovary syndrome (PCOS) are unknown and there is no effective cure for the disease. The aim of this study was to evaluate the alterations in serum oestradiol and adiponectin levels and in the expression of some important genes in the uterine and ovarian tissues of PCOS rats. The therapeutic effect of quercetin on PCOS was also assessed. Rats were divided into five groups: control, ethanol, quercetin (Q), PCOS and PCOS+Q. After 30 days of oral treatments, the rats' ovaries and uteri were removed and nesfatin-1, aromatase and adipoR1 expressions were quantified with real-time polymerase chain reaction. Serum adiponectin and oestradiol levels were evaluated using enzyme-linked immunosorbent assay technique. The results of this study showed that expression of nesfatin-1 and adipoR1 genes and adiponectin serum levels decreased in the PCOS rats, but aromatase expression and oestradiol level increased. Treatment with quercetin increased the adiponectin level and expression of adipoR1 and nesfatin-1 and decreased both the expression of aromatase and the oestradiol level. Quercetin improved PCOS by phytoestrogenic effects and mimicking oestrogen's function. Quercetin also affects important factors in both the uterus and ovary and could improve the obesity and the diabetic and infertility symptoms of PCOS.

[Effect of moxibustion at "Shenque" (CV8) and "Zusanli" (ST36) on expression of adiponectin and adiponectin receptor in Alzheimer's disease rats].

OBJECTIVE: To observe the effect of moxibustion on serum adiponectin content, and expression of adiponectin and adiponectin receptor in adipose tissue in Alzheimer's disease (AD) rats, so as to explore its mechanism underlying improvement of AD. METHODS: Fifty male SD rats were randomly divided into control, model, Shenque (CV8), Zusanli (ST36) and CV8＋ST36 groups (n＝10 in each group). The AD model was established by intraperitoneal injection of D-galactose (400 mg•kg－1•d－1) for 5 weeks and scopolamine hydrobromide (3 mg •kg－1•d－1) for 2 weeks. Moxibustion was applied to CV8, ST36 and CV8＋ST36 respectively for 3 moxa-cones every time, once daily for 5 weeks. Morris water maze tests were used to assess the rats' learning-memory ability. The contents of serum adiponectin were assayed using ELISA, and the expression of adiponectin and adiponectin receptor in the adipose tissue was detected by quantitative real-time PCR and Western blot, separately. RESULTS: Following modeling, the average escape latency of Morris water maze tests was significantly prolonged (P<0.05), the content of serum adiponectin and the expression level of adiponectin mRNA in adipose tissue were significantly decreased (P<0.01), the expression of adiponectin receptor protein significantly decreased in the model group relevant to the control group (P<0.01). After the intervention, the average escape latency was significantly shortened (P<0.05), the decreased serum adiponectin content and adiponectin mRNA expression, and the decreased adiponectin receptor protein expression in adipose tissue were all reversed in the 3 treatment groups (P<0.01，P<0.05). No significant differences were found among the three moxibustion groups in the above indexes (P>0.05). CONCLUSION: Moxibustion at CV8, ST36 and CV8＋ST36 is effective in up-regulating serum adiponectin content，adiponectin mRNA expression and adiponectin receptor protein expression in adipose tissue, which may provide evidence for clinical election of acupoints.

Dietary ß-Conglycinin Modulates Insulin Sensitivity, Body Fat Mass, and Lipid Metabolism in Obese Otsuka Long-Evans Tokushima Fatty (OLETF) Rats.

The physiological effects of dietary ß-conglycinin (ß-CON), one of the major components of soy protein (SOY), were examined in an obese animal model. Prior studies show that ß-CON intake decreases plasma triglycerides and visceral adipose tissue weight, and increases plasma adiponectin in rodents. Since plasma adiponectin is known to affect both lipid and glucose metabolism, feeding a diet containing ß-CON could modulate insulin sensitivity. Therefore, we examined the effects of dietary ß-CON on insulin sensitivity and blood glucose levels, as well as lipid metabolism in obese Otsuka Long-Evans Tokushima Fatty (OLETF) rats (pre-symptomatic stage of type 2 diabetes mellitus). Male OLETF rats (6 weeks old) were fed diets containing 20% protein such as casein (CAS), CAS replaced with soy protein (SOY), or ß-CON at a proportion of 50% for 13 weeks. Fasting blood glucose levels were measured every 3 weeks, and an insulin tolerance test (ITT; 0.75 IU/kg body weight) was conducted at week 12. During the feeding period, fasting blood glucose was comparable among the groups. Insulin sensitivity measured by the ITT revealed that the SOY and ß-CON diets decreased blood glucose levels at 30 min after intraperitoneal insulin injection (vs. CAS diet). In addition, the ß-CON diet increased plasma adiponectin concentrations, hepatic gene expression of insulin receptor substrate (IRS) 2, and muscle gene expression of adiponectin receptor 1 (AdipoR1) and IRS1, and with a decrease in plasma insulin concentration. Finally, the ß-CON diet decreased the mesenteric adipose tissue weight and liver triglyceride concentration compared to the CAS diet. These results suggest that the metabolic effects of dietary ß-CON are mediated by increasing plasma adiponectin to increase insulin sensitivity and influence the hepatic lipid metabolism in obese OLETF rats.

(-)-Hydroxycitric Acid Suppresses Lipid Droplet Accumulation and Accelerates Energy Metabolism via Activation of the Adiponectin-AMPK Signaling Pathway in Broiler Chickens.

(-)-Hydroxycitric acid (HCA) inhibits the deposition of fat in animals and humans, while the molecular mechanism is still unclear. The present study investigated the effect and mechanism of (-)-HCA's regulation of lipid, glucose, and energy metabolism in broiler chickens. The current results showed that (-)-HCA decreased the accumulation of lipid droplets and triglyceride content by reducing fatty acid synthase protein level and enhancing phosphorylation of acetyl-CoA carboxylase protein level. (-)-HCA accelerated carbohydrate aerobic metabolisms by increasing the activities of phosphofructokinase-1, pyruvate dehydrogenase, succinate dehydrogenase, and malate dehydrogenase. Furthermore, (-)-HCA increased adiponectin receptor 1 mRNA level and enhanced phospho-AMPKα, peroxisome proliferator-activated receptor gamma coactivator-1α, nuclear respiratory factor-1, and mitochondrial transcription factor A protein levels in broiler chickens. These data indicated that (-)-HCA reduced lipid droplet accumulation, improved glucose catabolism, and accelerated energy metabolism in broiler chickens, possibly via activation of adiponectin-AMPK signaling pathway. These results revealed the biochemical mechanism of (-)-HCA-mediated fat accumulation and the prevention of metabolic disorder-related diseases in broiler chickens.

Suppression of Hyperglycemia and Hepatic Steatosis by Black-Soybean-Leaf Extract via Enhanced Adiponectin-Receptor Signaling and AMPK Activation.

Yellow-soybean-leaf extract includes kaempferol glycosides and pheophorbides that reduce obesity and plasma glucose levels. This study researched the molecular mechanisms underlying the glucose-lowering effect of the extract of black-soybean leaves (EBL), which mainly contains quercetin glycosides and isorhamnetin glycosides, in mice with high-fat-diet (HFD)-induced obesity and diabetes and in HepG2 cells. Twelve weeks of EBL supplementation decreased body weight and fasting glucose, glycated hemoglobin, insulin, triglyceride, and nonesterified fatty acid levels. Histological analyses manifested that EBL suppressed hepatic steatosis. Interestingly, EBL significantly improved plasma adiponectin levels and increased adiponectin-receptor-gene ( AdipoR1 and AdipoR2) expression in the liver. EBL restored the effects of HFD on hepatic AMP-activated protein kinase (AMPK) and on the family of peroxisome proliferator-activated receptors (PPARα, PPARδ, and PPARγ), which are associated with fatty acid metabolism and are downstream of the adiponectin receptors. Hence, EBL effectively diminished hyperglycemia and hepatic steatosis through enhancing adiponectin-induced signaling and AMPK activation in the liver.

Docosanoids and elovanoids from omega-3 fatty acids are pro-homeostatic modulators of inflammatory responses, cell damage and neuroprotection.

The functional significance of the selective enrichment of the omega-3 essential fatty acid docosahexaenoic acid (DHA; 22C and 6 double bonds) in cellular membrane phospholipids of the nervous system is being clarified by defining its specific roles on membrane protein function and by the uncovering of the bioactive mediators, docosanoids and elovanoids (ELVs). Here, we describe the preferential uptake and DHA metabolism in photoreceptors and brain as well as the significance of the Adiponectin receptor 1 in DHA retention and photoreceptor cell (PRC) survival. We now know that this integral membrane protein is engaged in DHA retention as a necessary event for the function of PRCs and retinal pigment epithelial (RPE) cells. We present an overview of how a) NPD1 selectively mediates preconditioning rescue of RPE and PR cells; b) NPD1 restores aberrant neuronal networks in experimental epileptogenesis; c) the decreased ability to biosynthesize NPD1 in memory hippocampal areas of early stages of Alzheimer's disease takes place; d) NPD1 protection of dopaminergic circuits in an in vitro model using neurotoxins; and e) bioactivity elicited by DHA and NPD1 activate a neuroprotective gene-expression program that includes the expression of Bcl-2 family members affected by Aß42, DHA, or NPD1. In addition, we highlight ELOVL4 (ELOngation of Very Long chain fatty acids-4), specifically the neurological and ophthalmological consequences of its mutations, and their role in providing precursors for the biosynthesis of ELVs. Then we outline evidence of ELVs ability to protect RPE cells, which sustain PRC integrity. In the last section, we present a summary of the protective bioactivity of docosanoids and ELVs in experimental ischemic stroke. The identification of early mechanisms of neural cell survival mediated by DHA-synthesized ELVs and docosanoids contributes to the understanding of cell function, pro-homeostatic cellular modulation, inflammatory responses, and innate immunity, opening avenues for prevention and therapeutic applications in neurotrauma, stroke and neurodegenerative diseases.