Molecular Medicine最新文献

Background: Macrophages play an important role in the pathogenesis of ulcerative colitis (UC). We will explore the effects of sodium butyrate (SB) on macrophage function.

Methods: The targets of butyric acid were identified using SwissTargetPrediction database and surface plasmon resonance (SPR). Limited proteolysis mass spectrometry (Lip-MS) was used to further investigate the binding sites of butyric acid with its targets and molecular docking was employed to simulate their binding modes. Macrophage polarization model was established with lipopolysaccharide (LPS) in vitro. Takeda G protein-coupled receptor 5 (TGR5) and β-arrestin2 expression and macrophage polarization markers were detected with or without SB.

Results: TGR5 was identified as the target of butyric acid. Moreover, the amino acid regions 275-286 and 321-330 of TGR5 (GPBAR1 [275-286] and GPBAR1 [321-330]) were the potential binding regions for butyric acid. Based on molecular docking analysis, butyric acid formed effective hydrogen-bonding interactions with ASP-284 and TYR-287 of TGR5. In cell experiments, LPS inhibited the expression of TGR5, β-arrestin2, IL-10, ARG1, and CD206 and increased the expression of IL-1β, iNOS, and CD86, while SB reversed the effect of LPS. SBI-115, a TGR5 antagonist, and knockdown of β-arrestin2 inhibited the effect of sodium butyrate. INT-777, a TGR5 agonist, reversed the inhibitory effect of knockdown of β-arrestin2.

Conclusion: SB inhibited M1-like polarization and promoted M2-like polarization induced by LPS via TGR5/β-arrestin2 in RAW264.7 cells and TGR5 was the target of SB.

Prostate cancer (PCa) is a highly common type of malignancy and affects millions of men in the world since it is easy to recur or emerge therapy resistance. Therefore, it is urgent to find novel treatments for PCa patients. In the current study, we found that tegaserod maleate (TM), an FDA-approved agent, inhibited proliferation, colony formation, migration as well as invasion, caused the arrest of the cell cycle, and promoted apoptosis of PCa cells in vitro. In addition, TM suppressed the tumor growth in the cell-derived xenograft (CDX) mouse model in vivo. Mechanistically, TM exerted anti-tumor effects via downregulating GLI2, and its downtream targets, thus inhibiting the sonic hedgehog (SHH) signaling pathway. In brief, our findings demonstrated that TM effectively inhibited the activities of PCa cells by suppressing the SHH signaling pathway and provided a potential new agent for the treatment of PCa.

Background: Myocardial infarction (MI) remains a leading cause of mortality globally, often resulting in irreversible damage to cardiomyocytes. Ferroptosis, a recently identified form of regulated cell death driven by iron-dependent lipid peroxidation, has emerged as a significant contributor to post-MI cardiac injury. The endoplasmic reticulum (ER) stress response has been implicated in exacerbating ferroptosis.

Methods: Here, we investigated the potential of Dioscin, a natural compound known for its diverse pharmacological properties, in mitigating ferroptosis in cardiomyocytes following MI by targeting ER stress.

Results: In animal models subjected to MI, administration of Dioscin notably improved cardiac function, reduced infarct size by approximately 24%, and prevented adverse remodeling, highlighting its therapeutic potential. Through in vitro and in vivo models of MI, we demonstrated that Dioscin treatment significantly attenuates ferroptosis in cardiomyocytes, as evidenced by a decrease in lipid peroxidation by about 19% and preserved mitochondrial integrity. Moreover, Dioscin exerted its protective effects by inhibiting ER stress markers, such as the phosphorylation levels of PERK and eIF2α proteins, and the expression levels of BIP and ATF4 proteins, thus disrupting the ER stress-mediated signaling cascade associated with ferroptosis.

Conclusion: Overall, our findings suggested that Dioscin holds promise as a therapeutic agent against post-MI cardiac injury by mitigating ferroptosis via the suppression of ER stress. Further investigations into the precise molecular mechanisms and clinical translation of Dioscin's cardioprotective effects are warranted, offering a potential avenue for novel therapeutic interventions in MI-related cardiac complications.

Background: Polycystic ovary syndrome (PCOS) is a common gynecological disease accompanied by multiple clinical features, including anovulation, hyperandrogenism, and polycystic ovarian morphology, leading to infertility. Formononetin (FMN), which is a major bioactive isoflavone compound in Astragalus membranaceus, exerts anti-inflammatory effects. However, whether FMN is effective in the treatment of PCOS remains unknown. This study aims to explore the effects and the possible mechanisms of FMN in PCOS.

Methods: Dehydroepiandrosterone (DHEA)-induced PCOS rats and dihydrotestosterone (DHT)-induced PCOS cell models were established. Fifty rats were randomly assigned into five groups of 10 rats each: Control, PCOS, PCOS + FMN (15 mg/kg), PCOS + FMN (30 mg/kg), and PCOS + FMN (60 mg/kg). Fasting blood glucose, insulin, luteinizing hormone, follicle-stimulating hormone, testosterone, and estradiol were detected in DHEA-induced PCOS rats. Ovarian histological changes and apoptosis were evaluated utilizing H&E and TUNEL staining. Subsequently, the effects of FMN on oxidative stress and inflammatory responses in the DHEA-induced PCOS rat model and DHT-induced PCOS cell model were explored. Besides, the function of FMN on cell viability and apoptosis in DHT-induced PCOS cell model were explored by using CCK-8 assay and flow cytometry. Protein expression was detected via western blot and immunofluorescence staining in the DHEA-induced PCOS rat model and DHT-induced PCOS cell model.

Results: FMN alleviated PCOS symptoms and reduced inflammation, cell apoptosis, and oxidative stress in DHEA-induced PCOS rats and DHT-induced KGN cells. Additionally, FMN suppressed NLRP3 inflammasome activation in both models. In the DHT-induced PCOS cell model, nigericin (a activator of NLRP3) reversed the functions of FMN on inflammation, apoptosis, and oxidative stress.

Conclusion: These findings demonstrated that FMN could alleviate PCOS by repressing inflammation, apoptosis, as well as oxidative stress in vivo and in vitro via inhibition of the NLRP3 inflammasome.

Highlights: 1. FMN improved PCOS symptoms. 2. FMN alleviated cell apoptosis, inflammation and oxidative stress in PCOS. 3. FMN inhibited the activation of NLRP3 inflammasome in PCOS.

The incidence of obesity is increasing annually worldwide. A high-fat diet (HFD) causes intestinal barrier damage, but effective interventions are currently unavailable. Our previous work demonstrated the therapeutic effect of nobiletin on obese mice; thus, we hypothesized that nobiletin could reverse HFD-induced damage to the intestinal barrier. Male C57BL/6 J mice were orally administered nobiletin for 14 d. After identification, the obese mice were equally divided into three groups: the HFD group, the low-dose (NOL, 100 mg/kg/d) group and the high-dose nobiletin (NOH, 200 mg/kg/d) group. A normal control group (CON) was also included. Hematoxylin and eosin (HE) staining and immunofluorescence were used to observe the intestinal barrier. RT-qPCR was used to determine the transcriptomic levels of genes involved in intestinal barrier integrity and lipid metabolism. The results revealed that intestinal tight proteins, including ZO-1 and Occludin, were significantly reduced in HFD-fed mice but markedly restored after nobiletin intervention, particularly in NOH mice. Improvements in the intestinal barrier and lipid metabolism associated with major histocompatibility complex class II (MHC-II) and relevant elements were revealed after nobiletin intervention. Enrichment analysis revealed that MHC-II plays an important role in the restoration of the intestinal barrier. Taken together, nobiletin restored intestinal barrier integrity and lipid metabolism by regulating MHC-II expression.

Background: Neuropathic pain (NP) is a debilitating condition caused by lesion or dysfunction in the somatosensory nervous system. Accumulation of advanced oxidation protein products (AOPPs) is implicated in mechanical hyperalgesia. However, the effects of AOPPs on NP remain unclear.

Methods: A rat model of NP was established by chronic constriction injury (CCI) and employed to evaluate the changes of mechanical withdrawal threshold, thermal and cold withdrawal latency, as well as AOPPs levels. The effects of AOPPs on the activation of satellite glial cells (SGCs) in the dorsal root ganglion (DRG), receptor for advanced glycation end-products (RAGE) expression, and NF-κB signaling pathway activation were also investigated using western blotting, immunofluorescence, and the Fluo4-AM fluorescence probe for calcium signaling. Additionally, oxidative stress levels and inflammatory cytokine production in SGCs, triggered by AOPPs exposure, were measured through the DCFH-DA probe for ROS detection and ELISA kits for cytokine quantification.

Results: CCI significantly elevated the AOPPs levels in the plasma and sciatic nerve and caused AOPPs accumulation in the DRG. Exogenous AOPPs activated SGCs, increased reactive oxygen species and inflammatory response, upregulated the RAGE, and activated NF-κB signaling. The RAGE inhibitor FPS-ZM1 effectively inhibited AOPPs-induced SGC activation. Additionally, AOPPs intervention worsened CCI-induced hyperalgesia and neuroinflammation in vivo.

Conclusion: These results indicate that AOPPs exacerbate the SGC activation and NP following nerve injury, and AOPPs accumulation might play an important role in the pathogenesis of NP.

Background: Obesity is a significant risk factor for severe acute pancreatitis (SAP) and is typically associated with increased intestinal permeability. Understanding the role of specific molecules can help reduce the risk of developing SAP. Claudin 11 (CLDN11), a member of the Claudin family, regulates the permeability of various internal barriers. However, the role and mechanism of CLDN11 in the intestinal permeability of obesity-related SAP remain unclear.

Methods: We evaluated intestinal permeability and the expression of CLDN11 in experimental obesity-related SAP. A recombinant adeno-associated virus carrying CLDN11 was used to treat experimental obesity-related SAP. The interaction between CLDN11 mRNA and insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) protein was predicted through bioinformatics analysis and validated by RNA immunoprecipitation and RNA pull-down assay. Additionally, tumor necrosis factor-α (TNF-α) treatment in Caco-2 cells was conducted, and the IGF2BP3/CLDN11 axis was detected. Moreover, we conducted anti-TNFα therapy and evaluated intestinal permeability and pancreatic inflammation in experimental obesity-related SAP.

Results: Downregulation of CLDN11 was observed in the intestinal epithelial cells of experimental obesity-related SAP. When the expression of CLDN11 in intestinal epithelial cells of experimental obesity-related SAP was increased exogenously, intestinal epithelial permeability and pancreatic inflammation were relieved. Overexpression of CLDN11 reduced the paracellular permeability of Caco-2 monolayer cells, while knockdown of CLDN11 increased it. IGF2BP3 bound to and regulated the stability of CLDN11 mRNA. TNF-α treatment downregulated IGF2BP3 and CLDN11 in vitro. Anti-TNFα therapy reduced intestinal permeability, alleviated pancreatitis, and improved the expression of IGF2BP3 and CLDN11 in intestinal epithelial cells in experimental obesity-related SAP.

Conclusion: CLDN11 regulates intestinal permeability in obesity-related SAP. Mechanistically, an increase in TNF-α impaired the stability of IGF2BP3-dependent CLDN11 mRNA in obesity-related SAP.

Background: Long COVID or Post-acute sequelae of COVID-19 is an emerging syndrome, recognized in COVID-19 patients who suffer from mild to severe illness and do not recover completely. Most studies define Long COVID, through symptoms like fatigue, brain fog, joint pain, and headache prevailing four or more weeks post-initial infection. Global variations in Long COVID presentation and symptoms make it challenging to standardize features of Long COVID. Long COVID appears to be accompanied by an auto-immune multi-faceted syndrome where the virus or viral antigen persistence causes continuous stimulation of the immune response, resulting in multi-organ immune dysregulation.

Main text: This review is focused on understanding the risk factors of Long COVID with a special emphasis on the dysregulation of the gut-brain axis. Two proposed mechanisms are discussed here. The first mechanism is related to the dysfunction of angiotensin-converting enzyme 2 receptor due to Severe Acute Respiratory Syndrome Corona Virus 2 infection, leading to impaired mTOR pathway activation, reduced AMP secretion, and causing dysbiotic changes in the gut. Secondly, gut-brain axis dysregulation accompanied by decreased production of short-chain fatty acids, impaired enteroendocrine cell function, and increased leakiness of the gut, which favors translocation of pathogens or lipopolysaccharide in circulation causing the release of pro-inflammatory cytokines. The altered Hypothalamic-Pituitary-Adrenal axis is accompanied by the reduced level of neurotransmitter, and decreased stimulation of the vagus nerve, which may cause neuroinflammation and dysregulation of serum cortisol levels. The dysbiotic microbiome in Long COVID patients is characterized by a decrease in beneficial short chain fatty acid-producing bacteria (Faecalibacterium, Ruminococcus, Dorea, and Bifidobacterium) and an increase in opportunistic bacteria (Corynebacterium, Streptococcus, Enterococcus). This dysbiosis is transient and may be impacted by interventions including probiotics, and dietary supplements.

Conclusions: Further studies are required to understand the geographic variation, racial and ethnic differences in phenotypes of Long COVID, the influence of viral strains on existing and emerging phenotypes, to explore long-term effects of gut dysbiosis, and gut-brain axis dysregulation, as well as the potential role of diet and probiotics in alleviating those symptoms.

Background: Acute rejection (AR) is one of the significant factors contributing to poor prognosis in patients following kidney transplantation. Neutrophils are the main cause of early host-induced tissue injury. This paper intends to investigate the possible mechanisms of neutrophil involvement in acute rejection in renal transplantation.

Methods: Samples were analyzed for their relationship with immune cells using CIBERSORT. WGCNA was used to identify modules with high relevance to neutrophils and hub genes in the modules were extracted. The effect on neutrophil function after blocking formyl peptide receptor 1 (FPR1) was tested in vitro experiments. The effects of blocking FPR1 on neutrophil function as well as acute rejection were tested in vivo after constructing a mouse kidney transplant model.

Results: The proportion of neutrophils was higher in the AR group than in the non-rejection group, and FPR1 was identified as an important gene in the regulation of acute rejection in kidney transplantation by neutrophils. At the cellular level, blocking FPR1 inhibited the activation of the ERK1/2 pathway, decreased ferrous ion content, affected the expression of iron metabolism-related proteins, and suppressed the formation of NETs. In the acute rejection model of renal transplantation, blockade of FPR1 decreased graft neutrophil infiltration and NETs content. Meanwhile, blocking FPR1 attenuated graft injury during acute rejection.

Conclusion: This study found that FPR1 might be an important molecule involved in neutrophils during acute rejection of kidney transplantation, explored the relationship between kidney transplantation and neutrophils, and provided potential treatment methods for clinical practice.

Hepatocellular carcinoma is one of the most common malignant tumors, and radiotherapy plays a pivotal role in its therapeutic regimen. However, radiotherapy resistance is the main cause of therapeutic failure in patients. Our previous study revealed that Adiponectin Receptor 1 (AdipoR1) is involved in regulating radiation resistance in liver cancer patients treated with stereotactic body radiotherapy. To explore the mechanism, we performed high-throughput transcriptome sequencing of hepatocellular carcinoma cells with stable knockdown of AdipoR1. KEGG enrichment analysis indicated that the cell cycle and ubiquitination degradation pathways may be involved in the regulation of radiation resistance by AdipoR1.The knockdown of AdipoR1 can attenuate the radiation-induced G2/M phase arrest through cyclin B1.By the ubiquitination IP assay and a rescue experiment, we confirmed that CCNB1IP1 regulated the ubiquitination and degradation of cyclin B1. Combined with information from transcription factor database and AdipoR1 transcriptome sequencing, these results showed that estrogen receptor 1 (ESR1) may be a transcription factor of CCNB1IP1. We found that AdipoR1 promoted the translocation of ESR1 from the cytoplasm to the nucleus, and ESR1 inhibited the transcription of CCNB1IP1.Therefore, we propose that AdipoR1 regulates the ubiquitination level, cell cycle progression, and radiation resistance of HCC cells through the "AdipoR1 /ESR1/CCNB1IP1/cyclin B1" axis. This study will promote the development of novel targeted radiosensitizing drugs.