Therapeutic effects of AdipoRon on liver inflammation and fibrosis induced by CCl4 in mice

Effect of goose-derived adiponectin peptide gADP3 on LPS-induced inflammatory injury in goose liver

1. This study evaluated the effects and mechanisms of action of the peptide gADP3 on hepatic inflammatory injury induced by lipopolysaccharide (LPS).2. Hepatic inflammatory injury was induced in geese by intraperitoneal injection of LPS and gADP3, and the adiponectin receptor agonist AdipoRon (positive control) was used for potential amelioration. Serum inflammatory factor levels, liver function-related biochemical indicators and oxidative stress-related biochemical parameters in the liver tissues were determined. The expression levels of adiponectin and its receptors, inflammation and oxidative stress-related genes and key signalling molecules involved in adiponectin, inflammation and oxidative stress signalling pathways in liver tissues were detected.3. The peptide gADP3 alleviated inflammatory cell infiltration and hepatic inflammatory changes, reversed the decrease in serum albumin (ALB), total protein (TP), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) content or activity induced by LPS and increased the activity of the antioxidant enzymes CAT (catalase), SOD (superoxide dismutase) and GSH-Px (glutathione peroxidase).4. The peptide gADP3 upregulated the expression of antioxidant enzyme-related genes GCLC, HO-1 and NQO1 in liver tissues, decreased the levels of inflammatory factors like TNF-α, IL-1β, IL-6, IFN-γ and TGF-β and reduced mRNA expression levels of inflammatory-related genes TNF-α, IL-1β, iNOS and TGF-β. Additionally, it increased the mRNA and protein expression levels of adiponectin and its receptors, as well as key molecules in the adiponectin signalling pathway like AMPK and PPARα. In addition, gADP3 reversed the changes in mRNA or protein expression of inflammatory and oxidative stress signalling pathway-related genes P38MAPK, NF-κBP65, TLR4 and Nrf2 in liver tissues caused by LPS treatment.5. In conclusion, goose-derived adiponectin peptide gADP3, similar to the adiponectin receptor agonist AdipoRon, attenuated LPS-induced hepatic inflammatory injury in geese.

The adiponectin-PPARγ axis in hepatic stellate cells regulates liver fibrosis

Hepatic stellate cells (HSCs) are key drivers of local fibrosis. Adiponectin, conventionally thought of as an adipokine, is also expressed in quiescent HSCs. However, the impact of its local expression on the progression of liver fibrosis remains unclear. We recently generated a transgenic mouse line (Lrat-rtTA) that expresses the doxycycline-responsive transcriptional activator rtTA under the control of the HSC-specific lecithin retinol acyltransferase (Lrat) promoter, which enables us to specifically and inducibly overexpress or eliminate genes in these cells. The inducible elimination of HSCs protects mice from methionine/choline-deficient (MCD) diet-induced liver fibrosis, confirming their causal involvement in fibrosis development. We generated HSC-specific adiponectin overexpression and null models that demonstrate that HSC-specific adiponectin overexpression dramatically reduces liver fibrosis, whereas HSC-specific adiponectin elimination accelerates fibrosis progression. We identify a local adiponectin-peroxisome proliferator-activated receptor gamma (PPARγ) axis in HSCs that exerts a marked influence on the progression of local fibrosis, independent of circulating adiponectin derived from adipocytes.

AdipoRon mitigates liver fibrosis by suppressing serine/glycine biosynthesis through ATF4-dependent glutaminolysis

AdipoRon has been validated for its ability to reverse liver fibrosis, yet the underlying mechanisms remain to be thoroughly investigated. Collagen, predominantly synthesized and secreted in hepatic stellate cells (HSCs), relies on glycine as a crucial constituent. Activating transcription factor 4 (ATF4) serves as a pivotal transcriptional regulator in amino acid metabolism. Therefore, our objective is to explore the impact of AdipoRon on ATF4-mediated endoplasmic reticulum stress and amino acid metabolism in HSCs. We induced liver fibrosis in mice through intraperitoneal injection of CCl4 and administered AdipoRon (50 mg/kg) via gavage. In vitro studies were predominantly conducted using LX-2 cells. Our findings demonstrated that AdipoRon effectively suppressed ATF4-mediated endoplasmic reticulum stress in HSCs and assumed a crucial role in hindering serine/glycine biosynthesis. Interestingly, this inhibitory effect of AdipoRon on serine/glycine biosynthesis is regulated by PSAT1-mediated glutaminolysis, resulting in a subsequent decrease in collagen synthesis within HSCs. This study provides potential mechanistic insights into the treatment of liver fibrosis with AdipoRon.

Intranasal AdipoRon Mitigated Anxiety and Depression-Like Behaviors in 6-OHDA-Induced Parkinson 's Disease Rat Model: Going Beyond Motor Symptoms

Depression and anxiety are prevalent neuropsychiatric conditions among patients with Parkinson's disease (PD), which may manifest prior to motor symptoms. As levodopa, a prominent treatment for PD motor symptoms, provides few benefits for mood-related abnormalities, tackling non-motor symptoms is particularly important. AdipoRon (Ad), an adiponectin agonist, has demonstrated neuroprotective effects by suppressing neuroinflammatory responses and activating the AMPK/Sirt-1 signaling pathway. This study looked at the potential advantages and underlying mechanisms of intranasal Ad in a rat model of PD induced by 6-hydroxydopamine (6-OHDA). We found that Ad at doses of 1 and 10 µg for 21 days exhibited anxiolytic- and antidepressant effects in the open field (OF) test, elevated plus maze (EPM), sucrose splash test, and forced swimming test in a PD model caused by a unilateral 6-OHDA injection into the medial forebrain bundle (MFB). The Ad also lowered the levels of corticosterone in the blood, decreased inflammasome components (NLRP3, caspase 1, and IL-1β), and increased Sirt-1 protein levels in the prefrontal cortex (PFC) of PD rats. We conclude that Ad ameliorates anxious and depressive-like behaviors in the PD rat model through stimulating the AMPK/Sirt-1 signaling and blocking the NLRP3 inflammasome pathways in the PFC.

Efficacy of ADIPOR1 and ADIPOR2 peptide-agonist AdipoRon in preventing contracture in a rabbit model of arthrofibrosis

AdipoRon is an adiponectin receptor 1, 2 (ADIPOR1 and ADIPOR2) agonist with potential antifibrotic effects. Whether AdipoRon can mitigate joint stiffness in a rabbit model of arthrofibrosis is unknown. We examined the efficacy of intravenous (IV) AdipoRon at mitigating contracture in a rabbit model of knee arthrofibrosis. Fifty-six female New Zealand White rabbits were divided into three dosing groups: vehicle (dimethyl sulfoxide, DMSO), 2.5 mg/kg AdipoRon, and 5 mg/kg AdipoRon. AdipoRon, in DMSO, was administered IV preoperatively and for 5 days postoperatively (30 rabbits, Aim 1). AdipoRon was again dosed similarly after Kirschner wire (K-wire) removal at 8 weeks (26 rabbits; Aim 2). The primary outcome of joint passive extension angle (PEA,°) was measured at 8, 10, 12, 16, and 24 weeks following index surgery. At 24 weeks, rabbits were euthanized and limbs were harvested to measure posterior capsular stiffness (N cm/°). In Aim 1, the 5 mg/kg treated rabbits had a significant increase in PEA when compared to controls at 16-week (p < 0.05). In Aim 2, the 5 mg/kg treated rabbits had a significant increase in PEA when compared to controls at 10-week (p < 0.05). In both aims, no significant differences were observed at later time points. Capsular stiffness was no different in any group. We are the first to report the efficacy of IV AdipoRon in a rabbit model of arthrofibrosis. We identified a significant dose-dependent decrease in joint PEA at early time points; however, no differences were observed between groups at later time points. Clinical Significance: The present investigation provided the first assessment of AdipoRon's efficacy in mitigating knee stiffness in the current gold standard rabbit model of arthrofibrosis. Results of this investigation provided further evidence as to the potential role of AdipoRon as a preventative for arthrofibrosis in large mammals.

Anti-inflammatory properties of polysaccharides from edible fungi on health-promotion: a review

Edible fungus polysaccharides have garnered significant attention from scholars due to their safety and potential anti-inflammatory activity. However, comprehensive summaries of their anti-inflammatory properties are still rare. This paper provides a detailed overview of the anti-inflammatory effects and mechanisms of these polysaccharides, as well as their impact on inflammation-related diseases. Additionally, the relationship between their structure and anti-inflammatory activity is discussed. It is believed that this review will greatly enhance the understanding of the application of edible fungus polysaccharides in anti-inflammatory treatments, thereby significantly promoting the development and utilization of edible fungi.

AdipoRon reduces TGFβ1-mediated collagen deposition in vitro and alleviates knee stiffness in vivo

Arthrofibrosis, which causes joint motion restrictions, is a common complication following total knee arthroplasty (TKA). Key features associated with arthrofibrosis include myofibroblast activation, knee stiffness, and excessive scar tissue formation. We previously demonstrated that adiponectin levels are suppressed within the knee tissues of patients affected by arthrofibrosis and showed that AdipoRon, an adiponectin receptor agonist, exhibited anti-fibrotic properties in human mesenchymal stem cells. In this study, the therapeutic potential of AdipoRon was evaluated on TGFβ1-mediated myofibroblast differentiation of primary human knee fibroblasts and in a mouse model of knee stiffness. Picrosirius red staining revealed that AdipoRon reduced TGFβ1-induced collagen deposition in primary knee fibroblasts derived from patients undergoing primary TKA and revision TKA for arthrofibrosis. AdipoRon also reduced mRNA and protein levels of ACTA2, a key myofibroblast marker. RNA-seq analysis corroborated the anti-myofibrogenic effects of AdipoRon. In our knee stiffness mouse model, 6 weeks of knee immobilization, to induce a knee contracture, in conjunction with daily vehicle (DMSO) or AdipoRon (1, 5, and 25 mg/kg) via intraperitoneal injections were well tolerated based on animal behavior and weight measurements. Biomechanical testing demonstrated that passive extension angles (PEAs) of experimental knees were similar between vehicle and AdipoRon treatment groups in mice evaluated immediately following immobilization. Interestingly, relative to vehicle-treated mice, 5 mg/kg AdipoRon therapy improved the PEA of the experimental knees in mice that underwent 4 weeks of knee remobilization following the immobilization and therapy. Together, these studies revealed that AdipoRon may be an effective therapeutic modality for arthrofibrosis.

Potential therapeutic medicines for renal fibrosis: Small-molecule compounds and natural products

Renal fibrosis is the pathological change process of chronic kidney disease deteriorating continuously. When the renal organ is stimulated by external stimuli, it will trigger the damage and phenotypic changes of some intrinsic cells in the kidney. When the body's autoimmune regulation or external treatment is not prompted enough to restore the organ, the pathological process is gradually aggravating, inducing a large amount of intracellular collagen deposition, which leads to the appearance of fibrosis and scarring. The renal parenchyma (including glomeruli and tubules) begins to harden, making it difficult to repair the kidney lesions. In the process of gradual changes in the kidney tissue, the kidney units are severely damaged and the kidney function shows a progressive decline, eventually resulting in the clinical manifestation of end-stage renal failure, namely uremia. This review provides a brief description of the diagnosis, pathogenesis, and potential therapeutic inhibitors of renal fibrosis. Since renal fibrosis has not yet had a clear therapeutic target and related drugs, some potential targets and relevant inhibitors are discussed, especially pharmacological effects and interactions with targets. Some existing natural products have potential efficacy for renal fibrosis, which is also roughly summarized, hoping that this article would have reference significance for the treatment of renal fibrosis.

Diosmin ameliorates renal fibrosis through inhibition of inflammation by regulating SIRT3-mediated NF-κB p65 nuclear translocation

BACKGROUND

Renal fibrosis is considered an irreversible pathological process and the ultimate common pathway for the development of all types of chronic kidney diseases and renal failure. Diosmin is a natural flavonoid glycoside that has antioxidant, anti-inflammatory, and antifibrotic activities. However, whether Diosmin protects kidneys by inhibiting renal fibrosis is unknown. We aimed to investigate the role of Diosmin in renal interstitial fibrosis and to explore the underlying mechanisms.

METHODS

The UUO mouse model was established and gavaged with Diosmin (50 mg/kg·d and 100 mg/kg·d) for 14 days. HE staining, Masson staining, immunohistochemistry, western blotting and PCR were used to assess renal tissue injury and fibrosis. Elisa kits were used to detect the expression levels of IL-1β, IL-6, and TNF-α and the activity of SIRT3 in renal tissues. In addition, enrichment maps of RNA sequencing analyzed changes in signaling pathways. In vitro, human renal tubular epithelial cells (HK-2) were stimulated with TGF-β1 and then treated with diosmin (75 μM). The protein and mRNA expression levels of SIRT3 were detected in the cells. In addition, 3-TYP (selective inhibitor of SIRT3) and SIRT3 small interfering RNA (siRNA) were used to reduce SIRT3 levels in HK-2.

RESULTS

Diosmin attenuated UUO-induced renal fibrosis and TGF-β1-induced HK-2 fibrosis. In addition, Diosmin reduced IL-1β, IL-6, and TNF-α levels in kidney tissues and supernatants of HK-2 medium. Interestingly, Diosmin administration increased the enzymatic activity of SIRT3 in UUO kidneys. In addition, Diosmin significantly increased mRNA and protein expression of SIRT3 in vitro and in vivo. Inhibition of SIRT3 expression using 3-TYP or SIRT3 siRNA abolished the anti-inflammatory effects of diosmin in HK-2 cells. Enrichment map analysis by RNA sequencing indicates that the nuclear factor-kappa B (NF-κB) signaling pathway was inhibited in the Diosmin intervention group. Furthermore, we found that TGF-β1 increased the nuclear expression of nuclear NF-κB p65 but had little significant effect on the total intracellular expression of NF-κB p65. Additionally, Diosmin reduced TGF-β1-caused NF-κB p65 nuclear translocation. Knockdown of SIRT3 expression by SIRT3 siRNA increased the nuclear expression of NF-κB p65 and abolished the inhibition effect of Diosmin in NF-κB p65 expression.

CONCLUSIONS

Diosmin reduces renal inflammation and fibrosis, which is contributed by inhibiting nuclear translocation of NF-κB P65 through activating SIRT3.

AdipoRon and ADP355, adiponectin receptor agonists, in Metabolic-associated Fatty Liver Disease (MAFLD) and Nonalcoholic Steatohepatitis (NASH): A systematic review

Adiponectin replacement therapy holds the potential to benefit numerous human diseases, and ongoing research applies particular interest in how adiponectin acts against Metabolic-associated Fatty Liver Disease (MAFLD) and Nonalcoholic Steatohepatitis (NASH). However, the pharmacological limitations of the intact protein have prompted a focus on alternative options, specifically peptidic and small molecule agonists targeting the adiponectin receptor. AdipoRon is an extensively researched non-peptidic drug candidate in adiponectin replacement therapy. In turn, ADP355 is an adiponectin-based active short peptide. They have garnered significant attention due to their potential as substitutes for adiponectin. Researchers have studied AdipoRon's and ADP355's efficacy and therapeutic applications in various disease conditions. However, the effects of AdipoRon and ADP355 against NAFLD and NASH models advanced more, and no systematic review explored this area before. This systematic review was conceived to address the deficiency mentioned above and consider the lack of clinical evidence. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were utilized. To assess the risk of bias in systematic review, The Joanna Briggs Institute (JBI) Critical Appraisal Checklist was employed. Results from pre-clinical evidence show that AdipoRon and ADP355 represent promising effects in NAFLD and NASH-related models, including reducing hepatic steatosis, modulating inflammation, improving insulin sensitivity, enhancing mitochondrial function, and protecting against liver fibrosis. While AdipoRon and ADP355 exhibit promise in pre-clinical studies and experimental models, additional clinical trials are necessary to assess their effectiveness, safety, and potential translational therapeutic potential uses in NAFLD and NASH human cases.

The Adiponectin Receptor Agonist, ALY688: A Promising Therapeutic for Fibrosis in the Dystrophic Muscle

Duchenne muscular dystrophy (DMD) is one of the most devastating myopathies, where severe inflammation exacerbates disease progression. Previously, we demonstrated that adiponectin (ApN), a hormone with powerful pleiotropic effects, can efficiently improve the dystrophic phenotype. However, its practical therapeutic application is limited. In this study, we investigated ALY688, a small peptide ApN receptor agonist, as a potential novel treatment for DMD. Four-week-old mdx mice were subcutaneously treated for two months with ALY688 and then compared to untreated mdx and wild-type mice. In vivo and ex vivo tests were performed to assess muscle function and pathophysiology. Additionally, in vitro tests were conducted on human DMD myotubes. Our results showed that ALY688 significantly improved the physical performance of mice and exerted potent anti-inflammatory, anti-oxidative and anti-fibrotic actions on the dystrophic muscle. Additionally, ALY688 hampered myonecrosis, partly mediated by necroptosis, and enhanced the myogenic program. Some of these effects were also recapitulated in human DMD myotubes. ALY688's protective and beneficial properties were mainly mediated by the AMPK-PGC-1α axis, which led to suppression of NF-κβ and TGF-β. Our results demonstrate that an ApN mimic may be a promising and effective therapeutic prospect for a better management of DMD.

APN Expression in Serum and Corpus Luteum: Regulation of Luteal Steroidogenesis Is Possibly Dependent on the AdipoR2/AMPK Pathway in Goats

Adiponectin (APN) is an essential adipokine for a variety of reproductive processes. To investigate the role of APN in goat corpora lutea (CLs), CLs and sera from different luteal phases were collected for analysis. The results showed that the APN structure and content had no significant divergence in different luteal phases both in CLs and sera; however, high molecular weight APN was dominant in serum, while low molecular weight APN was more present in CLs. The luteal expression of both AdipoR1/2 and T-cadherin (T-Ca) increased on D11 and 17. APN and its receptors (AdipoR1/2 and T-Ca) were mainly expressed in goat luteal steroidogenic cells. The steroidogenesis and APN structure in pregnant CLs had a similar model as in the mid-cycle CLs. To further explore the effects and mechanisms of APN in CLs, steroidogenic cells from pregnant CLs were isolated to detect the AMPK-mediated pathway by the activation of APN (AdipoRon) and knockdown of APN receptors. The results revealed that P-AMPK in goat luteal cells increased after incubation with APN (1 μg/mL) or AdipoRon (25 μM) for 1 h, and progesterone (P4) and steroidogenic proteins levels (STAR/CYP11A1/HSD3B) decreased after 24 h. APN did not affect the steroidogenic protein expression when cells were pretreated with Compound C or SiAMPK. APN increased P-AMPK and reduced the CYP11A1 expression and P4 levels when cells were pretreated with SiAdipoR1 or SiT-Ca, while APN failed to affect P-AMPK, the CYP11A1 expression or the P4 levels when pretreated with SiAdipoR2. Therefore, the different structural forms of APN in CLs and sera may possess distinct functions; APN might regulate luteal steroidogenesis through AdipoR2 which is most likely dependent on AMPK.

The Safety of Adiponectin Receptor Agonist AdipoRon in a Rabbit Model of Arthrofibrosis

AdipoRon is an adiponectin receptor 1, 2 (ADIPOR1 and ADIPOR2) agonist with numerous reported physiological benefits in murine models of human disease, including a proposed reduction in fibrosis. However, AdipoRon has never been investigated in rabbits, which provide a robust model for orthopedic conditions. We examined the safety of intravenous (IV) AdipoRon in New Zealand White (NZW) female rabbits surgically stressed by a procedure that mimics human arthrofibrosis. Fifteen female NZW rabbits were prospectively studied using increasing AdipoRon doses based on established literature. AdipoRon was dissolved in dimethyl sulfoxide (DMSO), diluted in normal saline, and administered IV preoperatively and for 5 subsequent days postoperatively. The primary outcome was overall toxicity to rabbits, whereas secondary outcomes were change in rabbit weights and hemodynamics and defining acid-base characteristics of the drug formulation. Two rabbits expired during preoperative drug administration at 25 mg/kg. Remaining rabbits received preoperative doses of DMSO (vehicle), 2.5, 5, or 10 mg/kg of AdipoRon without complications. On postoperative day 1, one rabbit sustained a tonic-clonic seizure after their second dose of 10 mg/kg AdipoRon. The remaining 12 rabbits (4 in each group) received six serial doses of vehicle, 2.5, or 5 mg/kg of AdipoRon without adverse effects. All formulations of AdipoRon were within safe physiological pH ranges (4-5). We are the first to report the use of IV AdipoRon in a surgically stressed rabbit model of orthopedic disease. AdipoRon doses of 5 mg/kg or less appear to be well-tolerated in female NZW rabbits. Impact statement We provided the first in vivo toxicity assessment and dose optimization of a new antifibrotic experimental medication, AdipoRon, in a surgically stressed rabbit model of knee arthrofibrosis.

A Substituted-Rhodamine-Based Reversible Fluorescent Probe for In Vivo Quantification of Glutathione

Quantifying glutathione (GSH) in cells and organisms is of great significance for understanding the mechanism of oxidative stress in various physiological and pathological processes. However, the quantification by fluorescence bioimaging in living tissues has much stricter requirements than the "Petri dish"-cultured cells in flat plates. Based on the evaluation of the electronic structure and steric hindrance-tuned reactivity of phospha-substituted rhodamine with GSH, a reversible Förster resonance energy transfer (FRET) probe ZpSiP with a distinct performance (K_d =4.9 mM, t_1/2 =0.57 s, k=81 M^-1  s^-1 ) is developed for real time quantifying GSH in living cells. Furthermore, the near-infrared (NIR) probe succeeded in sensitively tracking the dynamics of GSH in the real organisms bearing tumors, chronic renal failure, and liver fibrosis for unveiling the related pathological processes. We believe that the advance in chemistry with quantitative analysis methods will initiate more promising progress and broad applications.

Naringenin is a Potential Immunomodulator for Inhibiting Liver Fibrosis by Inhibiting the cGAS-STING Pathway

BACKGROUND AND AIMS

Naringenin is an anti-inflammatory flavonoid that has been studied in chronic liver disease. The mechanism specific to its antifibrosis activity needs further investigation This study was to focused on the cyclic guanosine monophosphate-adenosine monophosphate synthase (cGAS) pathway in hepatic stellate cells and clarified the antifibrosis mechanism of naringenin.

METHODS

The relationship between the cGAS-stimulator of interferon genes (STING) pathway and liver fibrosis was analyzed using the Gene Expression Omnibus database. Histopathology, immunohistochemistry, fluorescence staining, Western blotting and polymerase chain reaction were performed to assess gene and protein expression levels associated with the cGAS pathway in clinical liver tissue samples and mouse livers. Molecular docking was performed to evaluate the relationship between naringenin and cGAS, and western blotting was performed to study the expression of inflammatory factors downstream of cGAS in vitro.

RESULTS

Clinical database analyses showed that the cGAS-STING pathway is involved in the occurrence of chronic liver disease. Naringenin ameliorated liver injury and liver fibrosis, decreased collagen deposition and cGAS expression, and inhibited inflammation in carbon tetrachloride (CCl₄)-treated mice. Molecular docking found that cGAS may be a direct target of naringenin. Consistent with the in vivo results, we verified the inhibitory effect of naringenin on activated hepatic stellate cells (HSCs). By using the cGAS-specific agonist double-stranded (ds)DNA, we showed that naringenin attenuated the activation of cGAS and its inflammatory factors affected by dsDNA. We verified that naringenin inhibited the cGAS-STING pathway, thereby reducing the secretion of inflammatory factors by HSCs to ameliorate liver fibrosis.

CONCLUSIONS

Interrupting the cGAS-STING pathway helped reverse the fibrosis process. Naringenin has potential as an antihepatic fibrosis drug.

AdipoRon Engages Microglia to Antinociception through the AdipoR1/AMPK Pathway in SNI Mice

Background

Microglia-associated neuroinflammation plays a crucial role in the initiation and development of neuropathic pain (NeuP). AdipoRon is an analog of adiponectin that exerts an anti-inflammatory effect in various diseases through the adiponectin receptor 1 (AdipoR1) signaling mechanism. Adenosine monophosphate-activated protein kinase (AMPK) is a downstream target of AdipoR1, and the AdipoR1/AMPK pathway is involved in the regulation of inflammation. This study is aimed at investigating whether AdipoRon could alleviate NeuP by inhibiting the expression of microglia-derived tumor necrosis factor-alpha (TNF-α) through the AdipoR1/AMPK pathway.

Methods

In vivo, the NeuP model was established in mice through the spared nerve injury. The von Frey test was used to detect the effect of AdipoRon on the mechanical paw withdrawal threshold. Western Blot was performed to detect the effects of AdipoRon on the expression of TNF-α, AdipoR1, AMPK, and p-AMPK. Immunofluorescence was performed to observe the effects of AdipoRon on spinal microglia. In vitro, lipopolysaccharide (LPS) was used to induce inflammatory responses in BV2 cells. The effect of AdipoRon on cell proliferation was detected by CCK-8. qPCR was used to examine the effects of AdipoRon on the expression of TNF-α and polarization markers. And the effect of AdipoRon on the AdipoR1/AMPK pathway was confirmed by Western Blot.

Results

Intraperitoneal injection of AdipoRon alleviated mechanical nociception in SNI mice, and the application of AdipoRon reduced the expression of TNF-α and the number of microglia in the ipsilateral spinal cord. Additionally, AdipoRon decreased the protein level of AdipoR1 and increased the protein level of p-AMPK in the ipsilateral spinal cord. In vitro, AdipoRon inhibited BV2 cell proliferation and reversed LPS-induced TNF-α expression and polarization imbalance. Furthermore, AdipoRon reversed the LPS-induced increase in AdipoR1 expression and decrease in p-AMPK expression in BV2 cells.

Conclusions

AdipoRon may alleviate NeuP by reducing microglia-derived TNF-α through the AdipoR1/AMPK pathway.

Targeting adipokines in polycystic ovary syndrome and related metabolic disorders: from experimental insights to clinical studies

Polycystic ovary syndrome (PCOS) affects approximately 15% of women of reproductive age worldwide. It is the most prevalent endocrine disorder with marked risks for female infertility, type 2 diabetes mellitus (T2DM), psychiatric disorders and gynecological cancers. Although the pathophysiology of PCOS remains largely elusive, growing evidence suggests a close link with obesity and its related metabolic disorders. As a highly active endocrine cell population, hypertrophic adipocytes in obesity have disturbed production of a vast array of adipokines, biologically active peptides that exert pleiotropic effects on homeostatic regulation of glucose and lipid metabolism. In parallel with their crucial roles in the pathophysiology of obesity-induced metabolic diseases, adipokines have recently been identified as promising targets for novel therapeutic strategies for multiple diseases. Current treatments for PCOS are suboptimal with insufficient alleviation of all symptoms. Novel findings in adipokine-targeted agents may provide important insight into the development of new drugs for PCOS. This Review presents an overview of the current understanding of mechanisms that link PCOS to obesity and highlights emerging evidence of adipose-ovary crosstalk as a pivotal mediator of PCOS pathogenesis. We summarize recent findings of preclinical and clinical studies that reveal the therapeutic potential of adipokine-targeted novel approaches to PCOS and its related metabolic disorders. We also discuss the critical gaps in knowledge that need to be addressed to guide the development of adipokine-based novel therapies for PCOS.

Influence of adiponectin and inflammatory cytokines in fatty degenerative atrophic muscle

Tendon rupture and nerve injury cause fatty infiltration of the skeletal muscle, and the adipokines secreted from the infiltrated adipocytes are known to contribute to chronic inflammation. Therefore, in this study, we evaluated the effects of the adipokines on chronic inflammation using a rat sciatic nerve-crushed injury model. In vitro and in vivo experiments showed that the expression of adiponectin was decreased (0.3-fold) and the expression of Il6 (~ 3.8-fold) and Tnf (~ 6.2-fold) was increased in the nerve-crushed group compared to that in the control group. It was also observed that the administration of an adiponectin receptor agonist decreased the levels of Il6 (0.38-fold) and Tnf (0.28-fold) and improved cellular viability (~ 1.9-fold) in vitro. Additionally, in the fatty infiltrated skeletal muscle, low adiponectin levels were found to be associated with chronic inflammation. Therefore, the local administration of adiponectin receptor agonists would prevent chronic inflammation.

Protective effects of AdipoRon on the liver of Huoyan goose fed a high-fat diet

Adiponectin can participate in the regulation of glucose and lipid metabolism, energy regulation, immune response, resistance to inflammation, oxidative stress, and apoptosis. Studies in rodents demonstrated that the small molecule compound adiponectin receptor agonist AdipoRon could activate the adiponectin receptor and played the same biological role as adiponectin. To explore the influence and regulation of AdipoRon on lipid metabolism disorder in Huoyan goose liver, in this study, goslings were fed a high-fat diet and then administered different dosages of AdipoRon. Subsequently, goose body weight, liver index, liver histopathological changes, blood glucose, blood and liver lipid, biochemical indexes related to liver function and oxidative stress, and the expression levels of genes related to lipid metabolism, inflammation, apoptosis, and autophagy, adiponectin and its receptors, key molecules of adiponectin involved signal pathway, and transcription factors in the liver, were detected using H&E and Oil red O staining, ELISA, and qRT-PCR methods. The results indicated that AdipoRon could alter the expression of lipid metabolism-related genes, inflammatory factors, apoptosis and autophagy genes, and adiponectin and its receptor genes in liver tissues through signaling pathways such as AMPK and p38 MAPK, as well as the involvement of transcription factors such as PPARα, PPARγ, SIRT1, and FOXO1, reduce the lipid content in blood and liver tissues of geese fed high-fat diets, improve liver antioxidant capacity, regulate apoptosis and autophagy of hepatocytes, and reduce liver inflammatory injury. Our study suggests that AdipoRon has a protective effect on fatty liver injury in goslings fed a high-fat diet.

Morchella importuna Polysaccharides Alleviate Carbon Tetrachloride-Induced Hepatic Oxidative Injury in Mice

This study aimed to investigate the effects of Morchella importuna polysaccharides (MIPs) on carbon tetrachloride (CCl4)-induced hepatic damage in mice. A total of 144 female mice were randomly assigned to four treatment groups, namely, control, CCl4, low-dose MIP (LMIP) group, and high-dose MIP (HMIP) group. After the 10-day experiment, serum and liver were sampled for biochemical and metabolomic analyses. The HMIPs markedly decreased the liver weight under CCl4 intoxication. Furthermore, the significantly elevated concentrations of five serum biochemical parameters, including alanine aminotransferase, aspartate aminotransferase, triglyceride, total cholesterol, and total bile acid under CCl4 treatment were subverted by MIP administration in a dose-dependent manner. Moreover, MIPs relieved the increased hepatic malonaldehyde and protein carbonyl content and the decreased superoxide dismutase and catalase contents caused by CCl4 intoxication. There was also a dose-dependent decrease in the CCl4-induced inflammatory indices, such as the levels of interleukin-1, interleukin-6, tumor necrosis factor-alpha, and myeloperoxidase, with MIP administration. Subsequent ultra-high performance liquid chromatography-tandem mass spectrometry-based serum metabolomics identified nine metabolites between the control and CCl4 groups and 10 metabolites between the HMIP and CCl4 groups, including some critical metabolites involved in flavonoid biosynthesis, amino acid metabolism, energy metabolism, and toxicant degradation. These novel findings indicate that MIPs may be of therapeutic value in alleviating the oxidative stress and inflammation caused by CCl4. Liquid chromatography-mass spectrometry-based metabolomics provides a valuable opportunity for identifying potential biomarkers and elucidating the protective mechanisms of medicinal mushrooms against hepatic oxidative injury.

PEGylated AdipoRon derivatives improve glucose and lipid metabolism under insulinopenic and high-fat diet conditions

The pleiotropic actions of adiponectin in improving cell survival and metabolism have motivated the development of small-molecule therapeutic agents for treating diabetes and lipotoxicity. AdipoRon is a synthetic agonist of the adiponectin receptors, yet is limited by its poor solubility and bioavailability. In this work, we expand on the protective effects of AdipoRon in pancreatic β-cells and examine how structural modifications could affect the activity, pharmacokinetics, and bioavailability of this small molecule. We describe a series of AdipoRon analogs containing amphiphilic ethylene glycol (PEG) chains. Among these, AdipoRonPEG5 induced pleiotropic effects in mice under insulinopenic and high-fat diet (HFD) conditions. While both AdipoRon and AdipoRonPEG5 substantially attenuate palmitate-induced lipotoxicity in INS-1 cells, only AdipoRonPEG5 treatment is accompanied by a significant reduction in cytotoxic ceramides. In vivo, AdipoRonPEG5 can substantially reduce pancreatic, hepatic, and serum ceramide species, with a concomitant increase in the corresponding sphingoid bases and improves insulin sensitivity of mice under HFD feeding conditions. Furthermore, hyperglycemia in streptozotocin (STZ)-induced insulinopenic adiponectin-null mice is also attenuated upon AdipoRonPEG5 treatment. Our results suggest that AdipoRonPEG5 is more effective in reducing ceramides and dihydroceramides in the liver of HFD-fed mice than AdipoRon, consistent with its potent activity in activating ceramidase in vitro in INS-1 cells. Additionally, these results indicate that the beneficial effects of AdipoRonPEG5 can be partially attributed to improved pharmacokinetics as compared with AdipoRon, thus suggesting that further derivatization may improve affinity and tissue-specific targeting.

Exogenous Plant gma-miR-159a, Identified by miRNA Library Functional Screening, Ameliorated Hepatic Stellate Cell Activation and Inflammation via Inhibiting GSK-3β-Mediated Pathways

Purpose

Plant-derived exogenous microRNAs (miRNAs) regulate human physiological functions by blocking the translation of target mRNAs. Although several computational approaches have been developed to elucidate the interactions of cross-species miRNAs and their targets in mammals, the number of verified plant miRNAs is still limited, and the biological roles of most exogenous plant miRNAs remain unknown.

Methods

A miRNA mimic library-based phenotypic screening, which contained 8394 plant mature miRNAs published in the official database miRbase, was performed to identify more novel bioactive plant miRNAs for the prevention of hepatic fibrosis. Inhibition of candidates for the activation of hepatic stellate cells (HSCs) and the underlying mechanisms were evaluated in TGF-β1- and PDGF-exposed HSC models. The protective effects of the candidates against CCl₄-induced liver fibrosis were evaluated in a mouse model.

Results

Among the 8394 plant mature miRNAs reported in the official database miRBase, five candidates were found to effectively inhibit the differentiation of HSCs. gma-miR-159a (miR159a) exerted the strongest inhibitory activities on both TGF-β1- and PDGF-induced HSC activation and proliferation by inhibiting the GSK-3β-mediated NF-κB and TGF-β1 pathways. Moreover, miR159a was mainly accumulated in the liver after intravenous injection, and it reduced CCl₄-induced hepatic fibrosis and inflammation in mice.

Conclusion

Results indicated that miR159a has the therapeutic potential for preventing hepatic fibrosis. This study provides a novel strategy for achieving natural nucleic acid drugs.

Starch based hydrogel NPs loaded by anthocyanins might treat glycogen storage at cardiomyopathy in animal fibrotic model

Many reports have been published recently confirmed the limitation of cargo molecules delivered into the heart. This failure is mostly associated with lymphatic or vascular channels washing or to the immune system recognition. Delivery of anthocyanins by encapsulation may augment it retention in the heart at early time points as the capsules are too large to wash out by lymphatic or venous channels and the physical structure of the capsule may shield the anthocyanins from immunoglobulins and cellular components of the immune system. In the current study, the cardiac dysfunction was induced by using carbon tetrachloride and then animal were treated orally by using anthocyanins incorporated into hydrogel NPs twice time /week for 4 weeks. The results showed anthocyanin loaded hydrogel NPs has ability to re-maintain the glycogen content in the liver and heart tissues of fibrotic group (13 ± 1.4 and 5 ± 0.7 μmol glucose/g tissue). Additionally, MDA and hydroxyproline were significantly reduced. PAS stain showed depletion of glycogen granules from heart tissue. It is concluded that starch based hydrogel loaded by anthocyanins can improve histological cardiac functions after their injury .

Physcion 8-O-β-glucopyranoside ameliorates liver fibrosis through inflammation inhibition by regulating SIRT3-mediated NF-κB P65 nuclear expression

Physcion 8-O-β-glucopyranoside (PSG), an anthraquinone extracted from Rumex japonicus Houtt, has various pharmacological effects, however, the effect of PSG on liver fibrosis and its related mechanism remain to be determined. We here showed that PSG ameliorated liver injury and liver fibrosis, decreased collagen deposition and inhibited inflammation in carbon tetrachloride (CCl4)-induced rats. Consistent with the in vivo results, PSG suppressed the transforming growth factor-β1 (TGF-β1)-induced cell viability, liver fibrosis and secretion of inflammatory factors in hepatic stellate cells (HSCs). Interestingly, PSG increased the enzyme activity and promoter activity of sirtuin 3 (SIRT3) in fibrotic liver and activated HSCs. In addition, PSG notably increased the mRNA and protein expression of SIRT3 both in vivo and in vitro. Depletion of SIRT3 either by using 3-TYP (SIRT3 selective inhibitor) or SIRT3 siRNA attenuated the anti-inflammatory effect of PSG in activated HSCs. Further study found that TGF-β1 increased the nuclear expression of NF-κB p65, but showed no obvious effect on the total NF-κB p65 expression. Compared to the control adenovirus (Ad.mk), overexpression of SIRT3 by infecting adenovirus encoding SIRT3 (Ad.SIRT3) notably decreased the nuclear expression of NF-κB p65 in activated HSCs. Our results demonstrated that PSG attenuated inflammation by regulating SIRT3-mediated NF-κB P65 nuclear expression in liver fibrosis, providing novel molecular insights into the anti-fibrotic effect of PSG.

A Potential Theragnostic Regulatory Axis for Arthrofibrosis Involving Adiponectin (ADIPOQ) Receptor 1 and 2 (ADIPOR1 and ADIPOR2), TGFβ1, and Smooth Muscle α-Actin (ACTA2)

(1) Background: Arthrofibrosis is a common cause of patient debility and dissatisfaction after total knee arthroplasty (TKA). The diversity of molecular pathways involved in arthrofibrosis disease progression suggest that effective treatments for arthrofibrosis may require a multimodal approach to counter the complex cellular mechanisms that direct disease pathogenesis. In this study, we leveraged RNA-seq data to define genes that are suppressed in arthrofibrosis patients and identified adiponectin (ADIPOQ) as a potential candidate. We hypothesized that signaling pathways activated by ADIPOQ and the cognate receptors ADIPOR1 and ADIPOR2 may prevent fibrosis-related events that contribute to arthrofibrosis. (2) Methods: Therefore, ADIPOR1 and ADIPOR2 were analyzed in a TGFβ1 inducible cell model for human myofibroblastogenesis by both loss- and gain-of-function experiments. (3) Results: Treatment with AdipoRon, which is a small molecule agonist of ADIPOR1 and ADIPOR2, decreased expression of collagens (COL1A1, COL3A1, and COL6A1) and the myofibroblast marker smooth muscle α-actin (ACTA2) at both mRNA and protein levels in basal and TGFβ1-induced cells. (4) Conclusions: Thus, ADIPOR1 and ADIPOR2 represent potential drug targets that may attenuate the pathogenesis of arthrofibrosis by suppressing TGFβ-dependent induction of myofibroblasts. These findings also suggest that AdipoRon therapy may reduce the development of arthrofibrosis by mediating anti-fibrotic effects in joint capsular tissues.

Sennoside A prevents liver fibrosis by binding DNMT1 and suppressing DNMT1-mediated PTEN hypermethylation in HSC activation and proliferation

Hepatic stellate cell (HSC) activation is an essential event during liver fibrogenesis. Phosphatase and tension homolog deleted on chromosome 10 (PTEN) is a negative regulator of this process. DNA methyltransferase 1 (DNMT1), which catalyzes DNA methylation and subsequently leads to the transcriptional repression of PTEN, is selectively induced in myofibroblasts from diseased livers. Sennoside A (SA), a major purgative constituent of senna and the Chinese herb rhubarb, is widely used in China and other Asian countries as an irritant laxative. SA is reported to improve hepatic steatosis. However, the effect and mechanism of SA on liver fibrosis remain largely unknown. We recently identified a novel strategy for protecting liver fibrosis via epigenetic modification by targeting DNMT1. A Surface Plasmon Resonance (SPR) assay first reported that SA could directly bind DNMT1 and inhibit its activity. Administration of SA significantly prevented liver fibrosis, as evidenced by the dramatic downregulation of α-smooth muscle actin (α-SMA) and type I collagen alpha-1 (Col1α1) protein levels in a CCl₄ -induced mouse hepatic fibrosis model and in TGF-β1-activated HSC-T6 cells, in vivo and in vitro. SA decreased the expression of Cyclin D1, CDK, and C-myc, indicating that SA may inhibit the activation and proliferation of TGF-β1-induced HSC-T6. Moreover, SA significantly promoted the expression of PTEN and remarkably inhibited the expression of p-AKT and p-ERK in vitro. Blocking PTEN or overexpressing DNMT1 could reduce the effect of SA on liver fibrosis. These data suggest that SA directly binds and inhibits the activity and that attenuated DNMT1-mediated PTEN hypermethylation caused the loss of PTEN expression, followed by the inhibition of the AKT and ERK pathways and prevented the development of liver fibrosis. Hence, SA might be employed as a promising natural supplement for liver fibrosis drug therapy.

Erythropoietin-Modified Mesenchymal Stem Cells Enhance Anti-fibrosis Efficacy in Mouse Liver Fibrosis Model

Background:

Mesenchymal stem cell (MSC)-based cell transplantation is an effective means of treating chronic liver injury, fibrosis and end-stage liver disease. However, extensive studies have found that only a small number of transplanted cells migrate to the site of injury or lesion, and repair efficacy is very limited.

Methods:

Bone marrow-derived MSCs (BM-MSCs) were generated that overexpressed the erythropoietin (EPO) gene using a lentivirus. Cell Counting Kit-8 was used to detect the viability of BM-MSCs after overexpressing EPO. Cell migration and apoptosis were verified using Boyden chamber and flow cytometry, respectively. Finally, the anti-fibrosis efficacy of EPO-MSCs was evaluated in vivo using immunohistochemical analysis.

Results:

EPO overexpression promoted cell viability and migration of BM-MSCs without inducing apoptosis, and EPO-MSC treatment significantly alleviated liver fibrosis in a carbon tetrachloride (CCl₄) induced mouse liver fibrosis model.

Conclusion:

EPO-MSCs enhance anti-fibrotic efficacy, with higher cell viability and stronger migration ability compared with treatment with BM-MSCs only. These findings support improving the efficiency of MSCs transplantation as a potential therapeutic strategy for liver fibrosis.