The adiponectin-derived peptide ALY688 protects against the development of metabolic dysfunction-associated steatohepatitis.

Metabolic dysfunction-associated steatohepatitis (MASH) is the severe form of non-alcoholic fatty liver disease which has a high potential to progress to cirrhosis and hepatocellular carcinoma, yet adequate effective therapies are lacking. Hypoadiponectinemia is causally involved in the pathogenesis of MASH. This study investigated the pharmacological effects of adiponectin replacement therapy with the adiponectin-derived peptide ALY688 (ALY688-SR) in a mouse model of MASH. Human induced pluripotent stem (iPS) cell-derived hepatocytes were used to test cytotoxicity and signaling of unmodified ALY688 in vitro. High-fat diet with low methionine and no added choline (CDAHF) was used to induce MASH and test the effects of ALY688-SR in vivo. Histological MASH activity score (NAS) and fibrosis score were determined to assess the effect of ALY688-SR. Transcriptional characterization of mice through RNA sequencing was performed to indicate potential molecular mechanisms involved. In cultured hepatocytes, ALY688 efficiently induced adiponectin-like signaling, including the AMP-activated protein kinase and p38 mitogen-activated protein kinase pathways, and did not elicit cytotoxicity. Administration of ALY688-SR in mice did not influence body weight but significantly ameliorated CDAHF-induced hepatic steatosis, inflammation, and fibrosis, therefore effectively preventing the development and progression of MASH. Mechanistically, ALY688-SR treatment markedly induced hepatic expression of genes involved in fatty acid oxidation, whereas it significantly suppressed the expression of pro-inflammatory and pro-fibrotic genes as demonstrated by transcriptomic analysis. ALY688-SR may represent an effective approach in MASH treatment. Its mode of action involves inhibition of hepatic steatosis, inflammation, and fibrosis, possibly via canonical adiponectin-mediated signaling.

Regulation and molecular mechanism of adiponectin on the proliferation, apoptosis, autophagy, and chemosensitivity of LN18 Glioma cell line.

This study aimed to explore the regulatory effects and associated mechanisms of adiponectin on apoptosis and proliferation in the LN18 glioma cell line through the AMPK and Akt signaling pathways. Additionally, we sought to elucidate the impact of adiponectin on the chemosensitivity of the LN18 glioma cell line to temozolomide (TMZ). The proliferation rate of glioma cells treated with adiponectin was assessed using the cholecystokinin (CCK8) assay. The Western blot analysis was employed to assess the expression of p-Akt, p-AMPK, p-mTOR, cleaved caspase3, Bax, Cyclin D1, and Cyclin B1 following adiponectin treatment. Cell apoptosis was quantified using AnnexinV/PI flow cytometry, while changes in the cell cycle were detected using PI staining flow cytometry. The findings revealed that adiponectin upregulates p-AMPK expression and downregulates p-mTOR expression in the PTEN wild-type glioma cell line LN18, with no discernible effect on p-Akt expression. Moreover, adiponectin inhibits the proliferation rate of the PTEN wild-type glioma cell line LN18, enhances the expression of cleaved caspase3 and Bax, and significantly elevates the apoptosis rate, as evidenced by AnnexinV/PI flow cytometry. Adiponectin was observed to suppress the expression of Cyclin D1 and Cyclin B1, increase the number of cells in the G1 phase, and promote autophagy. Additionally, adiponectin augments the expression of Beclin1 and the ratio of LC3II/I in the PTEN wild-type glioma cell line LN18, while decreasing p62 expression. In conclusion, this study posits that adiponectin holds therapeutic promise for glioma treatment. Furthermore, adiponectin enhances the inhibitory effect of TMZ on the proliferation rate of LN18 cells when treated with 0.1 mM and 1 mM TMZ. These results collectively suggest that adiponectin impedes proliferation, encourages apoptosis and autophagy in the LN18 glioma cell line, and heightens its sensitivity to the chemotherapeutic drug TMZ.

Inconsequential role for chemerin-like receptor 1 in the manifestation of ozone-induced lung pathophysiology in male mice.

We executed this study to determine if chemerin-like receptor 1 (CMKLR1), a Gi/o protein-coupled receptor expressed by leukocytes and non-leukocytes, contributes to the development of phenotypic features of non-atopic asthma, including airway hyperresponsiveness (AHR) to acetyl-ß-methylcholine chloride, lung hyperpermeability, airway epithelial cell desquamation, and lung inflammation. Accordingly, we quantified sequelae of non-atopic asthma in wild-type mice and mice incapable of expressing CMKLR1 (CMKLR1-deficient mice) following cessation of acute inhalation exposure to either filtered room air (air) or ozone (O3), a criteria pollutant and non-atopic asthma stimulus. Following exposure to air, lung elastic recoil and airway responsiveness were greater while the quantity of adiponectin, a multi-functional adipocytokine, in bronchoalveolar lavage (BAL) fluid was lower in CMKLR1-deficient as compared to wild-type mice. Regardless of genotype, exposure to O3 caused AHR, lung hyperpermeability, airway epithelial cell desquamation, and lung inflammation. Nevertheless, except for minimal genotype-related effects on lung hyperpermeability and BAL adiponectin, we observed no other genotype-related differences following O3 exposure. In summary, we demonstrate that CMKLR1 limits the severity of innate airway responsiveness and lung elastic recoil but has a nominal effect on lung pathophysiology induced by acute exposure to O3.

Ischemia-induced cardiac dysfunction is exacerbated in adiponectin-knockout mice due to impaired autophagy flux.

Strategies to enhance autophagy flux have been suggested to improve outcomes in cardiac ischemic models. We explored the role of adiponectin in mediating cardiac autophagy under ischemic conditions induced by permanent coronary artery ligation. We studied the molecular mechanisms underlying adiponectin's cardio-protective effects in adiponectin knockout (Ad-KO) compared with wild-type (WT) mice subjected to ischemia by coronary artery ligation and H9c2 cardiomyocyte cell line exposed to hypoxia. Systemic infusion of a cathepsin-B activatable near-infrared probe as a biomarker for autophagy and detection via noninvasive three-dimensional fluorescence molecular tomography combined with computerized tomography to quantitate temporal changes, indicated increased activity in the myocardium of WT mice after myocardial infarction which was attenuated in Ad-KO. Seven days of ischemia increased myocardial adiponectin accumulation and elevated ULK1/AMPK phosphorylation and autophagy assessed by Western blotting for LC3 and p62, an outcome not observed in Ad-KO mice. Cell death, assessed by TUNEL analysis and the ratio of Bcl-2:Bax, plus cardiac dysfunction, measured using echocardiography with strain analysis, were exacerbated in Ad-KO mice. Using cellular models, we observed that adiponectin stimulated autophagy flux in isolated primary adult cardiomyocytes and increased basal and hypoxia-induced autophagy in H9c2 cells. Real-time temporal analysis of caspase-3/7 activation and caspase-3 Western blot indicated that adiponectin suppressed activation by hypoxia. Hypoxia-induced mitochondrial reactive oxygen species production and cell death were also attenuated by adiponectin. Importantly, the ability of adiponectin to reduce caspase-3/7 activation and cell death was not observed in autophagy-deficient cells generated by CRISPR-mediated deletion of Atg7. Collectively, our data indicate that adiponectin acts in an autophagy-dependent manner to attenuate cardiomyocyte caspase-3/7 activation and cell death in response to hypoxia in vitro and ischemia in mice.

The Role of Adipocytokines and their Receptors in Prostate Cancer: Adiponectin May Protect Against Progression.

BACKGROUND/AIM: Obesity is correlated with an increased risk of developing malignancies, including prostate cancer. Adipocytokines, such as leptin and adiponectin, are a family of hormones derived from adipose tissue that are involved not only in metabolism, but also in the development and progression of various malignancies. However, little is known about their role in prostate cancer. This study aimed to determine how leptin, adiponectin, and their receptors impact the spread of prostate cancer. MATERIALS AND METHODS: We first performed immunohistochemical analysis of prostate cancer tissue microarrays to detect leptin, leptin receptor (Ob-R), adiponectin, and adiponectin receptors 1 and 2 (AdipoR1 and AdipoR2). Wound healing assays and western blot analysis were then performed in human prostate cancer cell lines. RESULTS: Immunohistochemistry showed that prostate tissue was not significantly positive for adiponectin. However, its expression tended to decrease according to the International Society of Urological Pathology (ISUP) grade of prostate cancer (p=0.056). In prostate cancer cell lines, administration of the synthetic adiponectin AdipoRon suppressed cell migration as well as the expression of phospho-NF-[Formula: see text]B and cyclooxygenase-2, whereas leptin stimulated these effects. CONCLUSION: Adiponectin expression tended to be suppressed according to ISUP grade in prostate cancer tissues. In vitro, tumor cell migration was induced by leptin but suppressed by adiponectin. Targeting adipocytokines could be a novel treatment strategy for prostate cancer.

Liver-specific adiponectin gene therapy suppresses microglial NLRP3-inflammasome activation for treating Alzheimer's disease.

Adiponectin (APN) is an adipokine which predominantly expresses in adipocytes with neuroprotective and anti-inflammatory effects. We have recently indicated that circulatory trimeric APN can enter the brain by crossing the blood-brain barrier (BBB) and modulate microglia-mediated neuroinflammation. Here, we found that the microglial NLR family pyrin domain containing 3 (NLRP3)-inflammasome activation was exacerbated in APN-/-5xFAD mice in age-dependent manner. The focus of this study was to develop a new and tractable therapeutic approach for treating Alzheimer's disease (AD)-related pathology in 5xFAD mice using peripheral APN gene therapy. We have generated and transduced adeno-associated virus (AAV2/8) expressing the mouse mutated APN gene (APNC39S) into the liver of 5xFAD mice that generated only low-molecular-weight trimeric APN (APNTri). Single dose of AAV2/8-APNC39S in the liver increased circulatory and cerebral APN levels indicating the overexpressed APNTri was able to cross the BBB. Overexpression of APNTri decreased both the soluble and fibrillar Aß in the brains of 5xFAD mice. AAV2/8-APNTri treatment reduced Aß-induced IL-1ß and IL-18 secretion by suppressing microglial NLRP3-inflammasome activation. The memory functions improved significantly in AAV-APNTri-treated 5xFAD mice with reduction of dystrophic neurites. These findings demonstrate that peripheral gene delivery to overexpress trimeric APN can be a potential therapy for AD.

Effects of mifepristone on adipocyte differentiation in mouse 3T3-L1 cells.

BACKGROUND: Both glucocorticoid receptor and peroxisome proliferator-activated receptor-γ (PPARγ) play a critical role in adipocyte differentiation. Mifepristone is not only an antagonist of the glucocorticoid receptor but also an agonist of PPARγ. Therefore, the present study investigated the effect of mifepristone on adipocyte differentiation. METHODS: Mouse 3T3-L1 cells were used as a model for adipocyte differentiation. The lipid droplet formation was evaluated with Bodipy493/503 staining and the expression of adipocyte markers [adiponectin and adipocyte fatty acid binding protein-4 (Fabp4)] was evaluated with quantitative PCR and immunoblot analyses for indication of adipocyte differentiation. siRNA and neutralizing antibodies were used to elucidate the molecular mechanism of mifepristone-induced adipocyte differentiation. Luciferase reporter assay was used to examine the effect of mifepristone on the promoter activity of PPAR-response element (PPRE). The DNA microarray analysis was used to characterize the transcriptome of the mifepristone-induced adipocytes. In vivo adipogenic effect of mifepristone was examined in mice. RESULTS: Mifepristone not only enhanced adipocyte differentiation induced by the conventional protocol consisting of insulin, dexamethasone and 3-isobutyl-1-methylxanthine but also induced adipocyte differentiation alone, as evidenced by lipid droplets formation and induction of the expression of adiponectin and Fabp4. These effects were inhibited by an adiponectin-neutralizing antibody and a PPARγ antagonist. Mifepristone activated the promoter activity of PPRE in a manner sensitive to PPARγ antagonist. A principal component analysis (PCA) of DNA microarray data revealed that the mifepristone-induced adipocytes represent some characteristics of the in situ adipocytes in normal adipose tissues to a greater extent than those induced by the conventional protocol. Mifepristone administration induced an increase in the weight of epididymal, perirenal and gluteofemoral adipose tissues. CONCLUSIONS: Mifepristone alone is capable of inducing adipocyte differentiation in 3T3-L1 cells and adipogenesis in vivo. PPARγ plays a critical role in the mifepristone-induced adipocyte differentiation. Mifepristone-induced adipocytes are closer to the in situ adipocytes than those induced by the conventional protocol. The present study proposes a single treatment with mifepristone as a novel protocol to induce more physiologically relevant adipocytes in 3T3-L1 cells than the conventional protocol.

The effects of green tea extract supplementation on body composition, obesity-related hormones and oxidative stress markers: a grade-assessed systematic review and dose-response meta-analysis of randomised controlled trials.

Research indicates that green tea extract (GTE) supplementation is beneficial for a range of conditions, including several forms of cancer, CVD and liver diseases; nevertheless, the existing evidence addressing its effects on body composition, oxidative stress and obesity-related hormones is inconclusive. This systematic review and meta-analysis aimed to investigate the effects of GTE supplementation on body composition (body mass (BM), body fat percentage (BFP), fat mass (FM), BMI, waist circumference (WC)), obesity-related hormones (leptin, adiponectin and ghrelin) and oxidative stress (malondialdehyde (MDA) and total antioxidant capacity (TAC)) markers. We searched proper databases, including PubMed/Medline, Scopus and Web of Science, up to July 2022 to recognise published randomised controlled trials (RCT) that investigated the effects of GTE supplementation on the markers mentioned above. A random effects model was used to carry out a meta-analysis. The heterogeneity among the studies was assessed using the I2 index. Among the initial 11 286 studies identified from an electronic database search, fifty-nine studies involving 3802 participants were eligible to be included in this meta-analysis. Pooled effect sizes indicated that BM, BFP, BMI and MDA significantly reduced following GTE supplementation. In addition, GTE supplementation increased adiponectin and TAC, with no effects on FM, leptin and ghrelin. Certainty of evidence across outcomes ranged from low to high. Our results suggest that GTE supplementation can attenuate oxidative stress, BM, BMI and BFP, which are thought to negatively affect human health. Moreover, GTE as a nutraceutical dietary supplement can increase TAC and adiponectin.

Adiponectin affects ileal contractility of mouse preparations.

Adiponectin (ADPN) has been reported to induce inhibitory effects on gastric motor activity, which, being a source of peripheral satiety signals, would contribute to the central anorexigenic effects of the hormone in rodents. However, peripheral satiety signals can also originate from the small intestine. Since there are no data on the effects of ADPN in this gut region, the present study aimed to investigate whether ADPN affects murine ileal contractility. Immunofluorescence experiments and Western blot were also performed to reveal the expression of ADPN receptors. Mechanical responses of ileal preparations were recorded in vitro via force-displacement transducers. Preparations showed a tetrodotoxin- and atropine-insensitive spontaneous contractile activity. Electrical field stimulation (EFS) induced tetrodotoxin- and atropine-sensitive contractile responses. ADPN induced a decay of the basal tension and decreased the amplitude of either the spontaneous contractility or the EFS-induced excitatory responses. All ADPN effects were abolished by the nitric oxide (NO) synthesis inhibitor NG-nitro l-arginine. The expression of the ADPN receptor, AdipoR1, but not AdipoR2, was also revealed in enteric glial cells. The present results offer the first evidence that ADPN acts on ileal preparations. The hormone exerts inhibitory effects, likely involving AdipoR1 on enteric glial cells and NO. From a physiological point of view, it could be hypothesized that the depressant action of ADPN on ileal contractility represents an additional peripheral satiety signal which, as also described for the ileal brake, could contribute to the central anorexigenic effects of the hormone.NEW & NOTEWORTHY This study provides the first evidence that adiponectin (ADPN) is able to act on ileal preparations. Functional results demonstrate that the hormone, other than causing a slight decay of the basal tension, depresses the amplitude of both spontaneous contractility and neurally induced excitatory responses of the mouse ileum through the involvement of nitric oxide. The expression of the ADPN receptor AdipoR1 and its localization on glial cells was revealed by Western blot and immunofluorescence analysis.

Homocysteine impairs the anticontractile/vasorelaxing activity of perivascular adipose tissue surrounding human internal mammary artery.

OBJECTIVES: Perivascular adipose tissue (PVAT) surrounding human internal mammary artery (IMA) possesses anticontractile property. Its function under pathological conditions is barely studied. We previously reported that homocysteine impairs the vasodilator function of IMA through endothelium and smooth muscle-dependent mechanisms. This study investigated the effect of homocysteine on the function of PVAT and the associated mechanisms. METHODS: Residual IMA tissues were collected from patients undergoing coronary artery bypass grafting. Vasoreactivity was studied using myograph. Adiponectin was measured by ELISA. Expressions of adiponectin receptors (AdipoRs), eNOS and p-eNOS were determined by RT-qPCR and Western blot. RESULTS: Exposure to homocysteine augmented the contractile responses of PVAT-intact IMA to U46619 and potassium chloride, regardless with or without endothelium. Such augmentation was also observed in skeletonized IMA with transferred, homocysteine-exposed PVAT. Homocysteine attenuated the relaxant response of PVAT-intact while endothelium-denuded vessels to acetylcholine. Homocysteine lowered adiponectin content in the PVAT, downregulated the expression of AdipoR1 and AdipoR2 as well as eNOS and p-eNOS in skeletonized IMA. The relaxant response of skeletonized IMA to AdipoR agonist AdipoRon was blunted by homocysteine or eNOS inhibitor, and homocysteine significantly attenuated the inhibitory effect of eNOS inhibitor on AdipoRon-induced relaxation. CONCLUSIONS: Homocysteine impairs the anticontractile/vasorelaxing activity of PVAT surrounding the IMA through inhibiting adiponectin/AdipoR/eNOS/nitric oxide signalling pathway.

Experimental periodontitis induced hypoadiponectinemia by IRE1α-mediated endoplasmic reticulum stress in adipocytes.

BACKGROUD: Hypoadiponectinemia is the important cause of insulin resistance. Recent studies have shown that periodontitis is associated with hypoadiponectinemia. The purpose of this study was to investigate the effect of periodontitis-induced endoplasmic reticulum stress (ERS) in visceral adipocytes on hypoadiponectinemia. METHODS: Rat periodontitis models were established by local ligation with silk around the bilateral maxillary second molars. Porphyromonas gingivalis-lipopolysaccharid (P.g-LPS) was also used to stimulate the visceral adipocytes in vitro. The protein expression levels of glucose regulated protein 78 (GRP78), inositol-requiring protein 1α (IRE1α), protein kinase RNA-like ER kinase (PERK), activating transcription factor 6 (ATF6) and adiponectin were detected. IRE1α lentiviruses were transfected into visceral adipocytes in vitro, and an IRE1α inhibitor (KIRA6) was injected in epididymal adipose tissue of rats to detect and verify the effect of ERS on adiponectin expression in visceral adipocytes in vivo. RESULTS: Hypoadiponectinemia was observed in periodontitis rat, and the expression levels of ERS key proteins GRP78 and the phosphorylation levels of IRE1α (p-IRE1α)/IRE1α in visceral adipocytes were increased, while the expression levels of adiponectin protein were decreased. After KIRA6 injection into epididymal adipose tissue of rats with periodontitis, adiponectin levels in visceral adipocytes increased, and serum adiponectin levels recovered to a certain extent. The protein expression levels of GRP78 and p-IRE1α/IRE1α were increased and adiponectin protein expression was decreased in P.g-LPS-induced visceral adipocytes. Overexpression of IRE1α further inhibited adiponectin expression in P.g-LPS-stimulated visceral adipocytes, and conversely, IRE1α inhibition restored adiponectin expression. CONCLUSIONS: Our findings suggest that periodontitis induces ERS in visceral adipocytes leading to hypoadiponectinemia. IRE1α is a key protein regulating adiponectin expression in visceral adipocytes.

AT1 receptors modulate ethanol-induced loss of anticontractile effect of perivascular adipose tissue.

Ethanol consumption activates renin-angiotensin-aldosterone system (RAAS), which plays a major role in the pro-contractile and hypertensive effects linked to ethanol. We hypothesized that ethanol consumption induces loss of the anticontractile effect of perivascular adipose tissue (PVAT)through RAAS-mediated mechanisms. We examined the contribution of angiotensin II type 1 receptors (AT1R) to ethanol-induced PVAT dysfunction. With this purpose, male Wistar Hannover rats were treated with ethanol 20 % (in volume ratio) and/or losartan (antagonist of AT1R; 10 mg/kg/day, gavage) for 9 weeks. Losartan prevented the increase in blood pressure and the loss of the anticontractile effect of PVAT induced by ethanol consumption. PVAT dysfunction occurred after 3 and 9 weeks of treatment with ethanol in an endothelium-dependent manner. Blockade of AT1R prevented ethanol-induced reduction of adiponectin levels in PVAT from ethanol-treated rats. Functional assays revealed that ethanol impaired the anticontractile effect of PVAT-derived angiotensin (1-7) and endothelial nitric oxide (NO). In conclusion, AT1R are implicated in ethanol-induced loss of the anticontractile effect of PVAT. In PVAT, AT1R activation decreases the production of adiponectin, a PVAT-derived factor that promotes vasorelaxation in an endothelium-dependent manner. In the endothelium, AT1R favors the production of superoxide (O2•-) leading to a reduction in NO bioavailability. These responses impair the vasodilator action induced by PVAT-derived angiotensin (1-7), which occurs via Mas receptors located in endothelial cells. Ethanol-induced PVAT dysfunction favors vascular hypercontractility, a response that could contribute to the hypertensive state associated with ethanol consumption.

Sesamol Alleviates High-Fat Diet-Induced Hepatic Insulin Resistance in C57BL/6 J Mice Through AMPK Activation Mediated by Adipose Adiponectin.

Sesamol is the major bioactive constituent isolated from sesame seeds and has a variety of bioactivities. However, its role and mechanism in liver insulin resistance remain unknown. The current study was designed to investigate the underlying adipose-liver crosstalk mechanism of sesamol ameliorating hepatic insulin sensitivity. The therapeutic effect of sesamol was evaluated in high-fat diet (HFD)-fed C57BL/6 J mice (100 mg/kg for 8 weeks, XYGW-2021-75) and the mechanism was further explored in HepG2 cells with/without adiponectin and adenosine 5 '-monophosphate-activated protein kinase (AMPK) inhibitor administration. Our in vivo data showed that sesamol reduced hepatic insulin resistance in HFD-induced mice with obesity by modulating protein expression levels of glycogen synthase (GS), phosphoenolpyruvate carboxykinase (PEPCK) and protein kinase B (AKT). Moreover, sesamol not only increased the serum and adipose tissue adiponectin concentrations but also activated the phosphorylation of AMPK in the liver. Furthermore, in vitro studies using recombinant human adiponectin and an AMPK inhibitor revealed that adiponectin and sesamol have a synergic impact on increasing glycogenesis and reducing gluconeogenesis, of which the effects could be attenuated by the AMPK inhibitor. Taken together, our results suggested that sesamol stimulated adiponectin secretion from adipocytes, whereby exhibited a co-effect on activating the downstream signal of hepatic AMPK, resulting in the alleviation of hepatic insulin resistance. The novel findings of sesamol on hepatic effects provides prospective therapeutic approaches to treat insulin resistance.

Adiponectin receptor 1-mediated stimulation of Cav3.2 channels in trigeminal ganglion neurons induces nociceptive behaviors in mice.

BACKGROUND: Adipokines, including adiponectin, are implicated in nociceptive pain; however, the underlying cellular and molecular mechanisms remain unknown. METHODS: Using electrophysiological recording, immunostaining, molecular biological approaches and animal behaviour tests, we elucidated a pivotal role of adiponectin in regulating membrane excitability and pain sensitivity by manipulating Cav3.2 channels in trigeminal ganglion (TG) neurons. RESULTS: Adiponectin enhanced T-type Ca2+ channel currents (IT) in TG neurons through the activation of adiponectin receptor 1 (adipoR1) but independently of heterotrimeric G protein-mediated signaling. Coimmunoprecipitation revealed a physical association between AdipoR1 and casein kinase II alpha-subunits (CK2α) in the TG, and inhibiting CK2 activity by chemical inhibitor or siRNA targeting CK2α prevented the adiponectin-induced IT response. Adiponectin significantly activated protein kinase C (PKC), and this effect was abrogated by CK2α knockdown. Adiponectin increased the membrane abundance of PKC beta1 (PKCß1). Blocking PKCß1 pharmacologically or genetically abrogated the adiponectin-induced IT increase. In heterologous expression systems, activation of adipoR1 induced a selective enhancement of Cav3.2 channel currents, dependent on PKCß1 signaling. Functionally, adiponectin increased TG neuronal excitability and induced mechanical pain hypersensitivity, both attenuated by T-type channel blockade. In a trigeminal neuralgia model induced by chronic constriction injury of infraorbital nerve, blockade of adipoR1 signaling suppressed mechanical allodynia, which was prevented by silencing Cav3.2. CONCLUSION: Our study elucidates a novel signaling cascade wherein adiponectin stimulates TG Cav3.2 channels via adipoR1 coupled to a novel CK2α-dependent PKCß1. This process induces neuronal hyperexcitability and pain hypersensitivity. Insight into adipoR-Cav3.2 signaling in sensory neurons provides attractive targets for pain treatment.

Cumulative effects of exercise training and consumption of propolis on managing diabetic dyslipidemia in adult women: a single-blind, randomized, controlled trial with pre-post-intervention assessments.

Dyslipidemia is an imbalance of various lipids, and propolis, as a natural resinous viscos mixture made by Apis mellifera L. could improve in this condition. In this single-blind, randomized trial, 60 women with type 2 diabetes and dyslipidemia were divided into four groups: (1) the patients who did not apply the combined training and 500 mg propolis capsules supplement (Control group); (2) subjects performed combined training, including aerobic and resistance training (EXR); (3) subjects received the 500 mg propolis supplement capsules (SUPP); (4) Subjects performed combined training along with receiving the 500 mg propolis supplement capsules (EXR + SUPP). We evaluated the concentration of CTRP12, SFRP5, interleukin-6 (IL6), superoxide dismutase (SOD), malondialdehyde (MDA), adiponectin, and total antioxidant capacity (TAC) before and after the intervention. MDA, TAC, IL6, CTRP12, SFRP5 IL6, adiponectin, and lipid profile levels ameliorated in the EXR + SUPP group. We found that 8 weeks of treatment by combined exercise training and propolis supplement decreased inflammation activity and increased antioxidant defense in women with diabetic dyslipidemia.Trial registration This study was registered in the Iranian Registry of Clinical Trials; IRCT code: IRCT20211229053561N1.

Injectable cell-targeting fiber rods to promote lipolysis and regulate inflammation for obesity treatment.

Obesity has become a worldwide public health problem and continues to be one of the leading causes of chronic diseases. Obesity treatment is challenged by large drug doses, high administration frequencies and severe side effects. Herein, we propose an antiobesity strategy through the local administration of HaRChr fiber rods loaded with chrysin and grafted with hyaluronic acid and AtsFRk fiber fragments loaded with raspberry ketone and grafted with adipocyte target sequences (ATSs). The hyaluronic acid grafts double the uptake levels of HaRChr by M1 macrophages to promote phenotype transformation from M1 to M2 through upregulating CD206 and downregulating CD86 expressions. ATS-mediated targeting and sustained release of raspberry ketone from AtsFRk increase the secretion of glycerol and adiponectin, and Oil red O staining shows much fewer lipid droplets in adipocytes. The combination treatment with AtsFRk and the conditioned media from HaRChr-treated macrophages elevates adiponectin levels, suggesting that M2 macrophages may secrete anti-inflammatory factors to stimulate adipocytes to produce adiponectin. Diet-induced obese mice showed significant weight losses of inguinal (49.7%) and epididymal (32.5%) adipose tissues after HaRChr/AtsFRk treatment, but no effect was observed on food intake. HaRChr/AtsFRk treatment reduces adipocyte volumes, lowers serum levels of triglycerides and total cholesterol and restores adiponectin levels to those of normal mice. In the meantime, HaRChr/AtsFRk treatment significantly elevates the gene expression of adiponectin and interleukin-10 and downregulates tissue necrosis factor-α expression in the inguinal adipose tissues. Thus, local injection of cell-targeting fiber rods and fragments demonstrates a feasible and effective antiobesity strategy through improving lipid metabolism and normalizing the inflammatory microenvironment.

Hypoadiponectinemia-induced upregulation of microRNA449b downregulating Nrf-1 aggravates cardiac ischemia-reperfusion injury in diabetic mice.

Diabetes enhances myocardial ischemic/reperfusion (MI/R) injury via an incompletely understood mechanism. Adiponectin (APN) is a cardioprotective adipokine suppressed by diabetes. However, how hypoadiponectinemia exacerbates cardiac injury remains incompletely understood. Dysregulation of miRNAs plays a significant role in disease development. However, whether hypoadiponectinemia alters cardiac miRNA profile, contributing to diabetic heart injury, remains unclear. Methods and Results: Wild-type (WT) and APN knockout (APN-KO) mice were subjected to MI/R. A cardiac microRNA profile was determined. Among 23 miRNAs increased in APN-KO mice following MI/R, miR-449b was most significantly upregulated (3.98-fold over WT mice). Administrating miR-449b mimic increased apoptosis, enlarged infarct size, and impaired cardiac function in WT mice. In contrast, anti-miR-449b decreased apoptosis, reduced infarct size, and improved cardiac function in APN-KO mice. Bioinformatic analysis predicted 73 miR-449b targeting genes, and GO analysis revealed oxidative stress as the top pathway regulated by these genes. Venn analysis followed by luciferase assay identified Nrf-1 and Ucp3 as the two most important miR-449b targets. In vivo administration of anti-miR-449b in APN-KO mice attenuated MI/R-stimulated superoxide overproduction. In vitro experiments demonstrated that high glucose/high lipid and simulated ischemia/reperfusion upregulated miR-449b and inhibited Nrf-1 and Ucp3 expression. These pathological effects were attenuated by anti-miR-449b or Nrf-1 overexpression. In a final attempt to validate our finding in a clinically relevant model, high-fat diet (HFD)-induced diabetic mice were subjected to MI/R and treated with anti-miR-449b or APN. Diabetes significantly increased miR-449b expression and downregulated Nrf-1 and Ucp3 expression. Administration of anti-miR-449b or APN preserved cardiac Nrf-1 expression, reduced cardiac oxidative stress, decreased apoptosis and infarct size, and improved cardiac function. Conclusion: We demonstrated for the first time that hypoadiponectinemia upregulates miR-449b and suppresses Nrf-1/Ucp3 expression, promoting oxidative stress and exacerbating MI/R injury in this population. Dysregulated APN/miR-449b/oxidative stress pathway is a potential therapeutic target against diabetic MI/R injury.

Mirabegron alleviates acetic acid-induced colitis in rats: Role of adiponectin and GSTM1/GSH detoxification pathway.

The prevalence of the debilitating chronic disease ulcerative colitis (UC) is increasing significantly. Mirabegron is a selective beta-3 adrenergic receptor (ß-3 AR) agonist used to treat an overactive bladder. Previous reports have demonstrated the antidiarrheal effect of ß-3AR agonists. Therefore, the current study aims to investigate the potential symptomatic effects of mirabegron on an experimental colitis model. The effects of oral administration of mirabegron (10 mg/kg) for seven days on rats receiving intra-rectal acetic acid instillation on the sixth day were examined using adult male Wistar rats. Sulfasalazine was utilized as a reference medication. Gross, microscopic, and biochemical observations of the experimental colitis were performed. The quantity and mucin content of goblet cells were found to have significantly decreased in the colitis group. In the colons of rats administered mirabegron, the number of goblet cells and the optical density of its mucin content increased. Mirabegron's ability to increase adiponectin in serum and decrease glutathione, GSTM1, and catalase in the colon may account for its protective effects. In addition, mirabegron decreased the expression of the proteins caspase-3 and NF-κB p65. It also prevented the activation of their upstream signaling receptors TLR4 and p-AKT by acetic acid administration. In conclusion, mirabegron prevented acetic acid-induced colitis in rats, possibly due to its antioxidant, anti-inflammatory, and antiapoptotic properties.

Adiponectin Attenuates Splenectomy-Induced Cognitive Deficits by Neuroinflammation and Oxidative Stress via TLR4/MyD88/NF-κb Signaling Pathway in Aged Rats.

Perioperative neurocognitive disorder (PND) is a common adverse event after surgical trauma in elderly patients. The pathogenesis of PND is still unclear. Adiponectin (APN) is a plasma protein secreted by adipose tissue. We have reported that a decreased APN expression is associated with PND patients. APN may be a promising therapeutic agent for PND. However, the neuroprotective mechanism of APN in PND is still unclear. In this study, 18 month old male Sprague-Dawley rats were assigned to six groups: the sham, sham + APN (intragastric (i.g.) administration of 10 µg/kg/day for 20 days before splenectomy), PND (splenectomy), PND + APN, PND + TAK-242 (intraperitoneal (i.p.) administration of 3 mg/kg TAK-242), and PND + APN + lipopolysaccharide (LPS) (i.p. administration of 2 mg/kg LPS). We first found that APN gastric infusion significantly improved learning and cognitive function in the Morris water maze (MWM) test after surgical trauma. Further experiments indicated that APN could inhibit the Toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88)/nuclear factor kappa B (NF-κb) p65 pathway to decrease the degree of oxidative damage (malondialdehyde (MDA) and superoxide dismutase (SOD)), microglia-mediated neuroinflammation (ionized calcium binding adapter molecule 1 (IBA1), caspase-1, tumor necrosis factor (TNF)-α, interleukin-1ß (IL-1ß), and interleukin-6 (IL-6)), and apoptosis (p53, Bcl2, Bax, and caspase 3) in hippocampus. By using LPS-specific agonist and TAK-242-specific inhibitor, the involvement of TLR4 engagement was confirmed. APN intragastric administration exerts a neuroprotective effect against cognitive deficits induced by peripheral trauma, and the possible mechanisms include the inhibition of neuroinflammation, oxidative stress, and apoptosis, mediated by the suppression of the TLR4/MyD88/NF-κb signaling pathway. We propose that oral APN may be a promising candidate for PND treatment.

Role of central adiponectin and its interactions with NPY and GABAergic systems on food intake in neonatal layer chicken.

BACKGROUND & AIM: Adiponectin is a member of the adipokine family and contributes to regulating energy homeostasis, reproduction, and various biological functions, such as insulin receptor signaling pathway sensitivity, mitochondrial biogenesis, oxidative metabolism, neurogenesis, and suppression of inflammation. This study aimed to investigate the effects of intracerebroventricular (ICV) injection of adiponectin and its interaction with the neuropeptide Y (NPY) and GABAergic systems on central appetite regulation in neonatal layer-type chickens. MATERIALS & METHODS: In this study, 6 experiments were conducted, each of which included 4 experimental groups. In the first experiment, the chickens were injected with saline and adiponectin (20.73, 41.45, and 62.18 nmol). In the second experiment, saline, adiponectin (62.18 nmol), B5063 (NPY1 receptor antagonist, 2.12 nmol), and simultaneous injections of adiponectin and B5063 were performed. Experiments 3 to 6 were done in the same way to experiment 1, but the chickens were injected with SF22 (NPY2 receptor antagonist, 2.66 nmol), SML0891 (NPY5 receptor antagonist, 2.89 nmol), picrotoxin (GABAA receptor antagonist, 0.89 nmol), CGP54626 (GABAB receptor antagonist, 0.047 nmol) instead of B5063. Feed consumption was measured 120 min after the injection. RESULTS: A dose-dependent increase in appetite was observed after the injection of adiponectin (20.73, 41.45, and 62.18 nmol) (P < 0.05). The injection of B5063 + adiponectin attenuated the hyperphagic effect of adiponectin (P < 0.05). In addition, co-injection of picrotoxin and adiponectin significantly decreased adiponectin-induced hyperphagia (P < 0.05). In addition, adiponectin significantly increased the number of steps, jumps, exploratory food, pecks, and standing time, while decreasing sitting time and rest time (P < 0.05). CONCLUSION: These results suggest that the hyperphagic effects of adiponectin are probably mediated through NPY1 and GABAA receptors in neonatal layer-type chickens.