Exploring the role and mechanism of hyperoside against cardiomyocyte injury in mice with myocardial infarction based on JAK2/STAT3 signaling pathway

BACKGROUND

Myocardial infarction (MI) is one of the most deadly diseases in the world. Hyperoside (Hyp) has been shown to have a protective effect on cardiovascular function through various signaling pathways, but whether it can protect myocardial infarction by regulating JAK2/STAT3 signaling pathway is unknown.

AIM OF THE STUDY

To investigate whether Hyp could protect the heart against myocardial infarction injury in mice by modulating JAK2/STAT3 signaling pathway and its potential mechanism.

METHODS

In vivo experiments, the myocardial infarction model was established by ligating the left anterior descending coronary artery (LAD) of male C57BL/6 mice permanently. The mice were divided into seven groups: sham group, MI group, MI+Hyp (9 mg/kg), MI+Hyp (18 mg/kg) group, MI+Hyp (36 mg/kg) group, MI+Captopril group (15 mg/kg) group and MI+Hyp (36 mg/kg)+AG490 (7.5 mg/kg) group. Each group of animals were given different concentrations of hyperoside, positive control drug or inhibitor of JAK2/STAT3 singaling. After 14 days of administration, the electrocardiogram (ECG), echocardiography and serum myocardial injury markers were examined; Slices of mouse myocardial tissue were assessed for histopathological changes by HE, Masson and Sirius Red staining. TTC and TUNEL staining were used to evaluate the myocardial infarction area and cardiomyocytes apoptosis respectively. The expression of JAK2/STAT3 signaling pathway, apoptosis and autophagy-related proteins were detected by western blot. In vitro experiments, rat H9c2 cardiomyocytes were deprived of oxygen and glucose (OGD) to stimulate myocardial ischemia. The experiment was divided into seven groups: Control group, OGD group, OGD+Hyp (20 μM) group, OGD+Hyp (40 μM) group, OGD+Hyp (80 μM), OGD+Captopril (10 μM) group and OGD+Hyp (80 μM)+AG490 (100 μM) group. Myocardial cell damage and redox index were measured 12 h after OGD treatment. ROS content in cardiomyocytes was detected by immunofluorescence. Cardiomyocytes apoptosis was detected by flow cytometry. The expressions of JAK2/STAT3 signaling pathway-related proteins, apoptosis and autophagy related proteins were detected by western blot.

RESULTS

In vivo, hyperoside could ameolirate ECG abnormality, increase cardiac function, reduce myocardial infarction size and significantly reduce myocardial fibrosis level and oxidation level. The experimental results in vitro showed that Hyp could reduce the ROS content in cardiomyocytes, decrease the level of oxidative stress and counteract the apoptosis induced by OGD injury . Both in vivo and in vitro experiments showed that hyperoside could increase phosphorylated JAK2 and STAT3, indicating that hyperoside could play a cardioprotective role by activating JAK2/STAT3 signaling pathway. It was also shown that hyperoside could increase the autophagy level of cardiomyocytes in vivo and in vitro. However the cardiomyocyte-protective effect of Hyp was abolished in combination with JAK2/ STAT3 signaling pathway inhibitor AG490. These results indicated that the protective effect of Hyp on cardiomyocyte injury was at least partially achieved through the activation of the JAK2/STAT3 signaling pathway.

CONCLUSION

Hyp can significantly improve cardiac function, ameliorate myocardial hypertrophy and myocardial remodeling in MI mice. The mechanism may be related to improving mitochondrial autophagy of cardiomyocytes to maintain the advantage of autophagy, and blocking apoptosis pathway through phagocytosis, thus suppressing apoptosis level of cardiomyocytes. These effects of Hyp are achieved, at least in part, by activating the JAK2/STAT3 signaling pathway.

The role of JAK2/STAT3 pathway in non-cytotoxic concentrations of DON-induced aggravation of inflammatory response in IL-10 deficient RAW264.7 cells

Deoxynivalenol (DON) as a mycotoxin was commonly found in food and cereals which can affect immune function and inflammatory response. The majority of foods contain DON at levels below the official limit. This study aimed to evaluate the effects of non-cytotoxic concentration of DON on inflammation and its mechanisms using the IL-10 gene-silenced RAW264.7 cell model. The results showed that a non-cytotoxic concentration of DON at 25 ng/ml aggravated IL-10 knockdown-induced inflammation, which was manifested by increasing IL-1β and TNF-α mRNA expression, migration and phagocytosis, decreasing IL-10 mRNA expression, and enhancing JAK2/STAT3 phosphorylation. Adding JAK2 inhibitor AG490 attenuated the aggravating effect of DON on IL-10 knockdown-induced inflammation. In conclusion, a non-cytotoxic concentration of DON enhances the inflammatory response through the JAK2/STAT3 signaling pathway when inflammation occurs in the body. These results indicated that non-cytotoxic concentrations of DON could aggravate inflammation when inflammation was induced by IL-10 knockdown, which increases vigilance against DON contamination at low concentration especially when an animal's body has inflammation.

Maternal exposure to di-(2-ethylhexyl) phthalate impaired the social interaction via activating microglia in male pups

Di-(2-ethylhexyl) phthalate (DEHP), a common endocrine-disrupting chemical (EDC), is widely used in daily articles, early exposure to DEHP is associated with many behavioral changes in pups. This study aimed to investigate the effects and underlying mechanisms of maternal exposure to DEHP on the impaired social interaction in pups. Pregnant rats were administered 0, 30, 300, or 750 mg/kg/d DEHP daily by oral gavage. Highly aggressive proliferating immortalized (HAPI) cells were treated with mono-(2-ethylhexyl) phthalate (MEHP) and tyrosine phosphorylation inhibitor (AG490). Our results showed that DEHP exposure induced the activation of microglias (MGs) via activating the janus kinase 2 / signal transducer and activator of transcription 3 (JAK2/STAT3) signaling pathway, and increased the level of pro-inflammatory factors, then impaired the social behavior in male pups, but not female pups. Moreover, MEHP exposure could also activate HAPI via activating this signaling pathway, and AG490 could inhibit the activation of this signaling pathway caused by MEHP. Therefore, we indicated that maternal exposure to DEHP could cause the gender-specific impaired social interaction in pups that might be related to the activation of MGs.

Overexpression of miR-506-3p reversed doxorubicin resistance in drug-resistant osteosarcoma cells

Background and objective: Osteosarcoma is a common primary malignant tumor of bone, and doxorubicin is one of the most widely used therapeutic drugs. While the problem of doxorubicin resistance limits the long-term treatment benefits in osteosarcoma patients. The role of miRNAs and their target genes in osteosarcoma have become increasingly prominent. Currently, there is no report on miR-506-3p reversing doxorubicin resistance by targeting STAT3 in osteosarcoma. The purpose of this study was to investigate the molecular mechanism that overexpression of miR-506-3p reverses doxorubicin resistance in drug-resistant osteosarcoma cells. Methods: Doxorubicin-resistant osteosarcoma cells (U-2OS/Dox) were constructed by intermittent stepwise increasing stoichiometry. The target genes of miR-506-3p were predicted by bioinformatics approach and the targeting relationship between miR-506-3p and STAT3 was detected using dual luciferase reporter assay. U-2OS/Dox cells were treated with miR-506-3p overexpression and STAT3 silencing respectively. Then Western blot and RT-qPCR were used to detect the protein and mRNA expression levels of JAK2/STAT3 signaling pathway, drug-resistant and apoptotic associated molecules. The migration and invasion were assessed by cell scratch assay and transwell assay. The cell proliferative viability and apoptosis were investigated by CCK8 assay and flow cytometry assay. Results: U-2OS/Dox cells were successfully constructed with a 14.4-fold resistance. MiR-506-3p is directly bound to the 3'-UTR of STAT3 mRNA. Compared with U-2OS cells, the mRNA expression of miR-506-3p was reduced in U-2OS/Dox cells. Overexpression of miR-506-3p decreased the mRNA expression levels of JAK2, STAT3, MDR1/ABCB1, MRP1/ABCC1, Survivin and Bcl-2, and decreased the protein expression levels of p-JAK2, STAT3, MDR1/ABCB1, MRP1/ABCC1, Survivin and Bcl-2, and conversely increased Bax expression. It also inhibited the proliferation, migration and invasion of U-2OS/Dox cells and promoted cells apoptosis. The results of STAT3 silencing experiments in the above indicators were consistent with that of miR-506-3p overexpression. Conclusion: Overexpression of miR-506-3p could inhibit the JAK2/STAT3 pathway and the malignant biological behaviors, then further reverse doxorubicin resistance in drug-resistant osteosarcoma cells. The study reported a new molecular mechanism for reversing the resistance of osteosarcoma to doxorubicin chemotherapy and provided theoretical support for solving the clinical problems of doxorubicin resistance in osteosarcoma.

Jolkinolide B ameliorates rheumatoid arthritis by regulating the JAK2/STAT3 signaling pathway

BACKGROUND

Jolkinolide B (JB), an ent‑abietane-type diterpenoid in Euphorbia plants, has various pharmacological activities, including anticancer, anti-inflammatory, and anti-tuberculosis activities. However, no previous studies have proven whether JB can be regarded as a targeted drug for the treatment of rheumatoid arthritis (RA).

PURPOSE

This study aimed to evaluate the anti-RA effects of JB and explore the potential mechanisms.

METHODS

Components and targets of JB and RA were identified in different databases, and potential targets and pathways were predicted by protein-protein interaction (PPI) network analysis and pathway enrichment analysis. Then, molecular docking and surface-plasmon resonance (SPR) were used to confirm the predict. The anti-arthritic effects of JB were studied in vivo with collagen-induced arthritis (CIA) rat model and in vitro with lipopolysaccharide (LPS) and interleukin-6 (IL-6)-induced RAW264.7 macrophage. Potential mechanisms were further verified by in vivo and in vitro experiments.

RESULTS

The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that Th17 cell differentiation, prolactin signaling pathway, and JAK/STAT signaling pathway might be associated with anti-RA effects of JB. Molecular docking and SPR results showed that JB bound effectively to JAK2. JB significantly decreased body weight loss, arthritis index, paw thickness, and synovial thickness in CIA rats. Histomorphological results suggested the protective effects of JB on CIA rats with ankle joint injury. Molecular biology analysis indicated that JB suppressed the mRNA expression of inflammatory factors in ankle joints for CIA rats and reduced the concentration of these factors in LPS- induced RAW264.7 macrophage. The protein expression level of the JAK2/STAT3 pathway was also significantly decreased by JB.

CONCLUSION

JB had a novel inhibitory effect on inflammation and bone destruction in CIA rats, and the mechanism might be related to the JAK2/STAT3 signaling pathway.

G3BP1 Interact with JAK2 mRNA to Promote the Malignant Progression of Nasopharyngeal Carcinoma via Activating JAK2/STAT3 Signaling Pathway

Ras-GTPase-activating protein (GAP)-binding protein 1 (G3BP1) is an RNA-binding protein implicated in various malignancies. However, its role in nasopharyngeal carcinoma (NPC) remains elusive. This study elucidates the potential regulation mechanisms of G3BP1 and its significance in NPC advancement. Through knockdown and overexpression approaches, we validate G3BP1's oncogenic role by promoting proliferation, migration, and invasion in vitro and in vivo. Moreover, G3BP1 emerges as a key regulator of the JAK2/STAT3 signaling pathway, augmenting JAK2 expression via mRNA binding. Notably, epigallocatechin gallate (EGCG), a green tea-derived antioxidant, counteracts G3BP1-mediated pathway activation. Clinical analysis reveals heightened G3BP1, JAK2, and p-STAT3 as powerful prognostic markers, with G3BP1's expression standing as an independent indicator of poorer outcomes for NPC patients. In conclusion, the study unveils the oncogenic prowess of G3BP1, its orchestration of the JAK2/STAT3 signaling pathway, and its pivotal role in NPC progression.

The effect and mechanism of Huangqin-Baishao herb pair in the treatment of dextran sulfate sodium-induced ulcerative colitis

Background

The haungqing (Scutellariae Radix) and baishao (Paeoniae Radix Alba) herb pair (HBHP) is a common prescribed herbal formula or is added to other traditional Chinese medicine (TCM) prescriptions to treat ulcerative colitis (UC). However, the underlying mechanism is unclear.

Purpose

Elucidate the efficacy and potential mechanism of HBHP against UC.

Methods

First, The UC model of mice induced by dextran sulfate sodium (DSS) was established. The mice were randomly divided into Control group, DSS group, SASP group (390 mg/kg), and HPHP group (1.95 g/kg), with 8 mice per group. Drugs were administrated via oral gavage for 7 days. Then, Disease activity index (DAI), length of the colon, histopathology, and changes in inflammatory cytokines in colonic tissues were analyzed to assess the effect of HBHP on UC. Besides, Network pharmacology was applied to identify the active compounds, core targets of HBHP in the treatment of UC, and the corresponding signaling pathways to explore the underlying mechanisms. Finally, Western blot (WB), immunohistochemistry (IHC) and molecular docking were performed to validate the results.

Results

HBHP significantly reduced DAI score and decreased colon length shortening in DSS-induced UC mice. The administration of HBHP was able to effectively alleviated mucosal ulceration and epithelial destruction. In addition, HBHP treatment obviously - reduced the expressions of TNF-α, IL-6, and IL-1β in colon tissues (p < 0.05 or p < 0.01). 35 bioactive compounds and 290 HBHP targets related to UC were obtained. Among them 3 key active compounds (baicalein, panicolin, and norwogonin) with higher degree values in the drug-compound-target network and 21 hub genes (STAT3, JAK2, SRC, AKT1, PIK3CA, and VEGFA, etc.) were identified. KEGG enrichment analysis suggested that HBHP's mechanisms mainly involve the JAK-STAT pathway. Abnormal activation of JAK/STAT signaling is believed to be involved in the pathogeneses of UC. Notably, WB and IHC showed that HBHP significantly down-regulated the protein expression levels of p-JAK2 (p < 0.05) and p-STAT3 (p < 0.05 or p < 0.01). JAK2 and STAT3 might be core targets for the action of HBHP; this possibility was also supported by molecular docking.

Conclusions

HBHP could alleviate DSS-induced UC, reduce tissue inflammation, and its mechanism might primarily be achieved by inhibiting JAK2/STAT3 signaling pathway. Meanwhile, our work revealed that network pharmacology combined with experimental verification is a cogent means of studying the mechanism of TCM.

Cucurbitacin C as an effective anti-cancer agent: unveiling its potential role against cholangiocarcinoma and mechanistic insights

BACKGROUND

Cholangiocarcinoma (CCA) is a malignant epithelial tumor characterized by a dismal prognosis. Given the lack of therapeutic strategies and durable treatment options currently available, identifying innovative treatments for CCA is an urgent unmet clinical need. Cucurbitacin C (CuC) is a distinct variant of the cucurbitacin family, displaying promising anti-cancer activity against various tumor types. The primary objective of our research is to elucidate the promising effects of CuC on CCA.

METHODS

The impact of CuC on CCA cell lines was assessed by cell count kit-8 assay, EdU staining assay, colony formation assay, wound-healing assay, and Transwell assay. Flow cytometric analysis was conducted to explore the function of CuC treatments on cell-cycle distribution and apoptosis in CCA cells. Computational biology and network pharmacology approaches were utilized to predict potential targets of CuC. Furthermore, a tumor xenograft mouse model was established using CCA cells to explore the anti-cancer effects of CuC in vivo.

RESULTS

Our research findings revealed that CuC exerted a suppressive effect on CCA cell progression. Cell viability assays, EdU staining assays, and colony formation assays demonstrated that CuC effectively suppressed viability and proliferation of CCA cells. Wound-healing assays and Transwell assays indicated that CuC effectively inhibits the migratory and invasive capabilities of CCA cells. Flow cytometry analysis elucidated that CuC played its anti-proliferative role in CCA cells by arresting G0/G1 phase and increasing apoptosis. Through bioinformatics and network pharmacology analysis, in conjunction with western blot analysis, we demonstrated CuC mediated the inhibition of CCA cell progression through modulation of JAK2/STAT3 pathway. Additionally, the CCA xenograft tumor model was established, and the results supported the inhibition of CuC treatment against CCA progression in vivo.

CONCLUSION

Our study demonstrates that CuC possesses notable capabilities to suppress cell proliferation, migration, and invasion in CCA. Importantly, the inhibitory effects of CuC on CCA progression are attributed to its modulation of the JAK2/STAT3 signaling pathway. Altogether, our study demonstrated that CuC holds promise as a prospective therapeutic agent for treating CCA.

DLGAP5 Regulates the Proliferation, Migration, Invasion, and Cell Cycle of Breast Cancer Cells via the JAK2/STAT3 Signaling Axis

The aim of this study was to discover new biomarkers to detect breast cancer (BC), which is an aggressive cancer with a high mortality rate. In this study, bioinformatic analyses (differential analysis, weighted gene co-expression network analysis, and machine learning) were performed to identify potential candidate genes for BC to study their molecular mechanisms. Furthermore, Quantitative Real-time PCR and immunohistochemistry assays were used to examine the protein and mRNA expression levels of a particular candidate gene (DLGAP5). And the effects of DLGAP5 on cell proliferation, migration, invasion, and cell cycle were further assessed using the Cell Counting Kit-8 assay, colony formation, Transwell, wound healing, and flow cytometry assays. Moreover, the changes in the JAK2/STAT3 signaling-pathway-related proteins were detected by Western Blot. A total of 44 overlapping genes were obtained by differential analysis and weighted gene co-expression network analysis, of which 25 genes were found in the most tightly connected cluster. Finally, NEK2, CKS2, UHRF1, DLGAP5, and FAM83D were considered as potential biomarkers of BC. Moreover, DLGAP5 was highly expressed in BC. The down-regulation of DLGAP5 may inhibit the proliferation, migration, invasion, and cell cycle of BC cells, and the opposite was true for DLGAP5 overexpression. Correspondingly, silencing or overexpression of the DLGAP5 gene inhibited or activated the JAK2/STAT3 signaling pathway, respectively. DLGAP5, as a potential biomarker of BC, may impact the cell proliferation, migration, invasion, cell cycle, and BC development by modulating the JAK2/STAT3 signaling pathway.

Autophagy Modulation and Its Implications on Glioblastoma Treatment

Autophagy is a vital cellular process that functions to degrade and recycle damaged organelles into basic metabolites. This allows a cell to adapt to a diverse range of challenging conditions. Autophagy assists in maintaining homeostasis, and it is tightly regulated by the cell. The disruption of autophagy has been associated with many diseases, such as neurodegenerative disorders and cancer. This review will center its discussion on providing an in-depth analysis of the current molecular understanding of autophagy and its relevance to brain tumors. We will delve into the current literature regarding the role of autophagy in glioma pathogenesis by exploring the major pathways of JAK2/STAT3 and PI3K/AKT/mTOR and summarizing the current therapeutic interventions and strategies for glioma treatment. These treatments will be evaluated on their potential for autophagy induction and the challenges associated with their utilization. By understanding the mechanism of autophagy, clinical applications for future therapeutics in treating gliomas can be better targeted.

miR-141-3p Regulates the Proliferation and Apoptosis of Endometrial-Myometrial Interface Smooth Muscle Cells in Adenomyosis Via JAK2/STAT3 Pathway

Adenomyosis (ADS) is a common benign gynecological disease. Abnormal proliferation at the endometrial-myometrial interface (EMI) plays a crucial role in the occurrence and progression of ADS. miR-141-3p is associated with cell proliferation and apoptosis. However, the specific mechanism of miR-141-3p in the etiology of ADS is still unknown. In this study, we explored the effects of miR-141-3p on the proliferation and apoptosis of ADS EMI smooth muscle cells (SMCs). We collected EMI tissues for the primary culture of SMCs from 25 patients diagnosed with ADS and 20 without ADS. Real-time quantitative polymerase chain reaction and western blot were used to measure the mRNA and protein expression levels of miR-141-3p, JAK2, STAT3, phospho-JAK2, and phospho-STAT3 in ADS EMI SMCs. The cell counting kit 8 assay and flow cytometry analysis were used to evaluate the proliferation and apoptosis of EMI SMCs. The miR-141-3p mimic/inhibitor was used to increase or decrease the expression level of miR-141-3p. We added WP1066 to block the phosphorylation of JAK2/STAT3 pathway components. The miR-141-3p levels were decreased, while JAK2 and STAT3 levels were increased in ADS EMI SMCs. miR-141-3p overexpression significantly inhibited the proliferation and enhanced the apoptosis of EMI SMCs, whereas a decrease in miR-141-3p expression level was connected to the opposite results. Meanwhile, inactivated JAK2/STAT3 pathway decreased proliferation and enhanced apoptosis of EMI SMCs after WP1066 treatment. Furthermore, rescue experiments confirmed that the JAK2/STAT3 pathway was the downstream pathway of miR-141-3p and reduced the effect of miR-141-3p on the proliferation and apoptosis of EMI SMCs. These results demonstrate that miR-141-3p regulates the proliferation and apoptosis of ADS EMI SMCs by modulating the JAK2/STAT3 pathway.

Acacetin restrains the malignancy of esophageal squamous carcinoma cells via regulating JAK2/STAT3 pathway

Acacetin is a natural flavonoid compound found in diverse plants, which has strong anti-inflammatory and anti-cancer activities. This work aimed at investigating how acacetin functions on esophageal squamous carcinoma cells. In this work, esophageal squamous carcinoma cell lines were subjected to increasing doses of acacetin, and the proliferative, migrative, invasive and apoptotic phenotypes were evaluated by a series of in vitro experiments. Genes related to acacetin and esophageal cancer were predicted by bioinformatics analysis. The levels of apoptosis-relevant proteins and JAK2/STAT3 pathway-relevant proteins in esophageal squamous carcinoma cells were probed by Western blot. It was revealed that acacetin could block the growth and aggressiveness of TE-1 and TE-10 cells and promote the apoptosis. Acacetin treatment induced bax's expression and repressed bcl-2's expression. Notably, acacetin inhibits JAK2/STAT3 pathway in esophageal squamous carcinoma cells. In summary, acacetin inhibits the malignant progression of esophageal squamous carcinoma via restraining JAK2/STAT3 signaling.

Artificial Downregulation of Ribosomal Protein L34 Restricts the Proliferation and Metastasis of Colorectal Cancer by Suppressing the JAK2/STAT3 Signaling Pathway

The highly conserved ribosomal protein L34 (RPL34) has been reported to play an essential role in the progression of diverse malignancies. RPL34 is aberrantly expressed in multiple cancers, although its significant in colorectal cancer (CRC) is currently unclear. Here, we demonstrated that RPL34 expression was higher in CRC tissues than in normal tissues. Upon RPL34 overexpression, the ability of proliferation, migration, invasion, and metastasis of CRC cells were significantly enhanced in vitro and in vivo. Furthermore, high expression of RPL34 accelerated cell cycle progression, activated the JAK2/STAT3 signaling pathway, and induced the epithelial-to-mesenchymal transition (EMT) program. Conversely, RPL34 silencing inhibited the CRC malignant progression. Utilizing immunoprecipitation assays, we identified the RPL34 interactor, the cullin-associated NEDD8-dissociated protein 1 (CAND1), which is a negative regulator of cullin-RING ligases. CAND1 overexpression reduced the ubiquitin level of RPL34 and stabilized RPL34 protein. CAND1 silencing in CRC cells resulted in a decrease in the ability of proliferation, migration, and invasion. CAND1 overexpression promoted CRC malignant phenotypes and induced EMT, and RPL34 knockdown rescued CAND1-induced CRC progression. In summary, our study indicates that RPL34 acts as a mediator, is stabilized by CAND1, and promotes proliferation and metastasis, in part, through the activation of the JAK2/STAT3 signaling pathway and induction of EMT in CRC.

TMT quantitative proteomics and network pharmacology reveal the mechanism by which asiaticoside regulates the JAK2/STAT3 signaling pathway to inhibit peritoneal fibrosis

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional Chinese medicine, Centella asiatica (L.) Urb., has been extensively utilized in clinics to treat a variety of fibrotic disorders. Asiaticoside (ASI), as an important active ingredient, has attracted much attention in this field. However, the effect of ASI on peritoneal fibrosis (PF) is still unclear. Therefore, we evaluated the benefits of ASI for PF and mesothelial-mesenchymal transition (MMT) and revealed the underlying mechanisms.

AIM OF STUDY

The objective of this investigation was to anticipate the potential molecular mechanism of ASI against peritoneal mesothelial cells (PMCs) MMT employing proteomics and network pharmacology, and to confirm it using in vivo and in vitro studies.

MATERIALS AND METHODS

The mesentery of peritoneal fibrosis mice and normal mice were analyzed quantitatively for proteins that were differentially expressed using a technique tandem mass tag (TMT). Next, the core target genes of ASI against PF were screened through network pharmacology analysis, and PPI and C-P‒T networks were constructed by Cytoscape Version 3.7.2. According to the findings of a GO and KEGG enrichment analysis of differential proteins and core target genes, the signaling pathway with a high correlation degree was selected as the key signaling pathway of ASI inhibiting the PMCs MMT for further molecular docking analysis and experimental verification.

RESULTS

TMT-based quantitative proteome analysis revealed the identification of 5727 proteins, of which 70 were downregulated and 178 were upregulated. Among them, the levels of STAT1, STAT2, and STAT3 in the mesentery of mice with peritoneal fibrosis were considerably lower than in the control group, indicating a role for the STAT family in the pathogenesis of peritoneal fibrosis. Then, a total of 98 ASI-PF-related targets were identified by network pharmacology analysis. JAK2 is one of the top 10 core target genes representing a potential therapeutic target. JAK/STAT signaling may represent a core pathway mediating PF effects by ASI. Molecular docking studies showed that ASI had the potential to interact favorably with target genes involved in the JAK/STAT signaling pathway, such as JAK2 and STAT3. The experimental results showed that ASI could significantly alleviate Chlorhexidine Gluconate (CG)-induced peritoneal histopathological changes and increase JAK2 and STAT3 phosphorylation levels. In TGF-β1-stimulated HMrSV5 cells, E-cadherin expression levels were dramatically reduced whereas Vimentin, p-JAK2, α-SMA, and p-STAT3 expression levels were considerably increased. ASI inhibited the TGF-β1-induced HMrSV5 cell MMT, decreased the activation of JAK2/STAT3 signaling, and increased the nuclear translocation of p-STAT3, which was consistent with the effect of the JAK2/STAT3 pathway inhibitor AG490.

CONCLUSION

ASI can inhibit PMCs MMT and alleviate PF by regulating the JAK2/STAT3 signaling pathway.

JAK2/STAT3 Signaling Pathway and Klotho Gene in Cadmium-induced Neurotoxicity In Vitro and In Vivo

Cadmium (Cd), a common heavy metal in the environment, is associated with cognitive impairment. In the present study, we carried out a preliminary inquiry to explore whether Cd causes neurotoxicity by regulating the JAK2/STAT3 signaling pathway and affecting the expression of klotho genes in vivo and in vitro, providing clues for the mechanism of Cd-induced cognitive dysfunction. The rat samples were injected with Cd chloride solution for 14 weeks, and the memory function of the rats was detected. Different concentrations of Cd and JAK2/STAT3 signaling pathway inhibitors were used to treat PC12 cells and thus detect the apoptosis rate. The protein expression levels of JAK2, p-JAK2, STAT3, p-STAT3, and klotho in rat and PC12 cell were detected by ELISA and Western blot, respectively. With the increase in exposure dose, the memory function of rats was severely impaired. The expression of p-JAK2 and p-STAT3 proteins was significantly up-regulated, whereas that of klotho was significantly down-regulated both in vivo and in vitro (p < 0.05). In comparison with the high-dose Cd exposure group, after adding tyrphostin AG490 (AG490), the apoptosis rate of PC12 cells increased, whereas the phosphorylation levels of JAK2 and STAT3 in the cells decreased significantly (p < 0.05). Cd exposure may cause neurotoxicity by regulating the JAK2/STAT3 signaling pathway and down-regulating klotho protein expression, leading to cognitive dysfunction.

SOCS3 Silencing Promotes Activation of Vocal Fold Fibroblasts via JAK2/STAT3 Signaling Pathway

Suppressor of cytokine signaling 3 (SOCS3) is a negative regulatory protein that has been identified as a key inhibitory regulator of JAK/STAT signaling pathway. However, the mutual regulatory relationship between SOCS3 and JAK2/STAT3 signaling pathway after vocal fold injury remains unclear. In this study, we used small interfering RNA (siRNA) to investigate the mechanism of SOCS3 regulating of fibroblasts through JAK2/STAT3 signaling pathway after vocal fold injury. Our data shows that SOCS3 silencing promotes the transformation of normal vocal fold fibroblasts (VFFs) into an fibrotic phenotype and activates the JAK2/STAT3 signaling pathway. JAK2 silencing significantly inhibits the increase in type I collagen and α-smooth muscle actin (α-SMA) secretion in VFFs induced by TGF-β but has no significant effect on normal VFFs. The silencing of SOCS3 and JAK2 reverses the fibrotic phenotype of VFFs induced by SOCS3 silencing. Therefore, we suggest that SOCS3 can affect the activation of vocal fold fibroblasts by regulating the JAK2/STAT3 signaling pathway after vocal fold injury. It provides a new insight for promoting the repair of vocal fold injury and preventing the formation of fibrosis.

Deoxynivalenol at No-Observed Adverse-Effect Levels Aggravates DSS-Induced Colitis through the JAK2/STAT3 Signaling Pathway in Mice

The etiology of inflammatory bowel diseases (IBDs) involves complex genetic and environmental factors such as mycotoxin contamination. Deoxynivalenol (DON), a well-known mycotoxin, contaminates food and feed and can induce intestinal injury and inflammatory response. The dose of DON in many foods is also below the limit, although the dose of DON exceeds the limit. The present study aims to evaluate the effects of the nontoxic dose of DON on colitis induced by dextran sodium sulfate (DSS) and the mechanism in mice. The results showed a nontoxic dose of DON at 50 μg/kg bw per day exacerbated DSS-induced colitis in mice as demonstrated by increased disease activity index, decreased colon length, increased morphological damage, decreased occludin and mucoprotein 2 expression, increased IL-1β and TNF-α expression, and decreased IL-10 expression. DON at 50 μg/kg bw per day enhanced JAK2/STAT3 phosphorylation induced by DSS. Adding JAK2 inhibitor AG490 attenuated the aggravating effects of DON on DSS-induced colitis by reversing the morphological damage, occludin and mucoprotein 2 expression increased, IL-1β and TNF-α expression increased, and IL-10 expression decreased. Taken together, a nontoxic dose of DON could aggravate DSS-induced colitis via the JAK2/STAT3 signaling pathway. This suggests that DON, below the standard limit dose, is also a risk for IBD and may be harmful to the health of humans and animals, which could provide the basis for establishing limits for DON.

PGK1 modulates balance between pro- and anti-inflammatory cytokines by interacting with ITI-H4

Inter-α-trypsin inhibitor heavy chain 4 (ITI-H4) is one of the acute phase proteins and is mainly related with inflammatory diseases such as bacterial bloodstream infection and recurrent pregnancy loss (RPL). In a previous study, ITI-H4 was reported to be cleaved by kallikrein B1 (KLKB1) and its cleaved form induces the imbalance between pro- and anti-inflammatory cytokines. Therefore, in this study, putative substrates of ITI-H4 were isolated by immunoprecipitation and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/MS) analysis. Of those, phosphoglycerate kinase 1 (PGK1) was found to be a binding protein of ITI-H4. PGK1 increases the level of ITI-H4 expression and blocks the cleavage of ITI-H4 mediated by KLKB1. It also inhibits pro-inflammatory response by inhibiting the JAK2/STAT3 signaling pathway. Therefore, PGK1, a novel binding partner of ITI-H4, is expected to have cellular functions in the pathogenesis of ITI-H4-related inflammatory diseases.

Pulsatilla saponin A Inhibits Proliferation and Induces Apoptosis in Diffuse Large Bcell Lymphoma Cells through the JAK2/STAT3 Signaling Pathway

OBJECTIVES

This study aimed to investigate the performance of Pulsatilla saponin A (PsA) in diffuse large B-cell lymphoma (DLBCL) cells.

METHODS

Proliferation, ELISA, apoptosis, cell cycle analysis, and assays were carried out to detect the growth and apoptosis in DLBCL cells. Western blotting was used to identify the change in the protein.

RESULTS

In cell assays, PsA significantly inhibited the growth and apoptosis in DLBCL cells. The IL-10 and TNF-α of OCI-LY10 and U2932 cells were reduced after 24 h PsA treatment. Bax, cleaved PARP, and cleaved Caspase-3 were increased, while Bcl-2 and C-Myc decreased after PsA treatment. IL-10 may regulate the expression of C-Myc protein in cells by activating the JAK2/STAT3 signaling pathway. PsA can inhibit the overexpression of p-JAK2 and p- STAT3 signaling pathways induced by IL-10 stimulants. The proliferation and apoptosis induced by PsA were confirmed in DLBCL cells.

CONCLUSION

Our findings revealed that PsA may exert its antitumor effect by causing G1 arrest and apoptosis in DLBCL cells. The mechanism of PsA regulating apoptosis in DLBCL cells is probably through the JAK2/STAT3 signaling pathway in vitro.

Oral squamous cell carcinoma cell-derived GM-CSF regulates PD-L1 expression in tumor-associated macrophages through the JAK2/STAT3 signaling pathway

Previous study reported that gastric cancer-derived granulocyte-macrophage colony-stimulating factor (GM-CSF) could mediate neutrophil activation and induce PD-L1 expression through JAK2/STAT3 signaling pathway. Moreover, this pathway in various cancers could also regulate PD-L1 expression of tumor cells. Therefore, our study aimed to investigate whether the JAK2/STAT3 pathway regulates PD-L1 expression in tumor-associated macrophages (TAMs) in oral squamous cell carcinoma (OSCC), which can help us achieve further understanding of immune escape mechanisms in OSCC. We induced human monocytes THP-1 into M0, M1, and M2 macrophages, and applied them to common medium and tumor-conditioned medium, the latter was collected from two types of OSCC cell line. Western blot and RT-PCR were used to detect PD-L1 expression and activation of JAK2/STAT3 pathway in macrophages under various conditions. We found that GM-CSF in tumor-conditioned medium from OSCC cells increased PD-L1 expression in M0 macrophages in a time-dependent manner. Moreover, both GM-CSF neutralizing antibody and JAK2/STAT3 pathway inhibitor AG490 could inhibited its up-regulation. In the meantime, we confirmed that GM-CSF indeed acted through JAK2/STAT3 pathway by measuring phosphorylation of key proteins in this pathway. Therefore, we concluded that OSCC cell-derived GM-CSF was able to up-regulate PD-L1 expression in TAMs through JAK2/STAT3 signaling pathway.

Lotus Bee Pollen Extract Inhibits Isoproterenol-Induced Hypertrophy via JAK2/STAT3 Signaling Pathway in Rat H9c2 Cells

Bee pollen possesses an anti-cardiomyocyte injury effect by reducing oxidative stress levels and inhibiting inflammatory response and apoptosis, but the possible effect mechanism has rarely been reported. This paper explores the effect of the extract of lotus bee pollen (LBPE) on cardiomyocyte hypertrophy (CH) and its mechanism. The main components of LBPE were identified via UPLC-QTOF MS. An isoproterenol-induced rat H9c2 CH model was subsequently used to evaluate the protection of LBPE on cells. LBPE (100, 250 and 500 μg∙mL^-1) reduced the surface area, total protein content and MDA content, and increased SOD activity and GSH content in CH model in a dose-dependent manner. Meanwhile, quantitative real-time PCR trials confirmed that LBPE reduced the gene expression levels of CH markers, pro-inflammatory cytokines and pro-apoptosis factors, and increased the Bcl-2 mRNA expression and Bcl-2/Bax ratio in a dose-dependent manner. Furthermore, target fishing, bioinformatics analysis and molecular docking suggested JAK2 could be a pivotal target protein for the main active ingredients in the LBPE against CH. Ultimately, Western blot (WB) trials confirmed that LBPE can dose-dependently inhibit the phosphorylation of JAK2 and STAT3. The results show that LBPE can protect against ISO-induced CH, possibly via targeting the JAK2/STAT3 pathway, also suggesting that LBPE may be a promising candidate against CH.

[Warm acupuncture stimulation improves cartilage damage and motor function by regulating JAK2/STAT3 signaling pathway in rabbits with knee osteoarthritis]

OBJECTIVE

To observe the effect of warm acupuncture on the expression of Janus protein tyrosine kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) signaling pathway and inflammatory factors of articular cartilage in rabbits with knee osteoarthritis (KOA), so as to explore its underlying mechanisms in improving KOA.

METHODS

New Zea-land rabbits were randomly divided into blank, model, warm acupuncture and medication groups (12 rabbits in each group). The KOA model was prepared by using the right hind limb tubular plaster extension fixation method. The rabbits in the warm acupuncture group received acupuncture of "Neixiyan"(EX-LE4),"Waixiyan"(ST35),"Heding"(EX-LE2) and "Zusanli"(ST36), followed by attaching an ignited moxa-stick segment to the acupuncture-handle. The treatment was conducted for 15 min, once a week for 4 weeks. The rabbits in the medication group received gavage of diclofenac sodium solution(0.35 mg/kg), once daily for 4 weeks. The dysfunction severity state of the rabbit's knee-joint was evaluated using Lequesne scale (0-3 points), and the histopathological changes of cartilage were observed under microscope after H.E. staining and the state of distribution of chondrocytes in different layers and the extracellular matrix was assessed using Mankin score (0-6 points). The contents of serum interleukin (IL)-6, tumor necrosis factor-α (TNF-α) and matrix metalloproteinase-9 (MMP-9) were measured by using ELISA, and the expression levels of p-JAK2/JAK2, p-STAT3/STAT3 and MMP-9 in knee cartilage tissue were detected using Western blot.

RESULTS

Compared with the blank group, the Lequesne score, Mankin score, and the contents of serum IL-6, TNF-α and MMP-9, and the ratios of p-JAK2/JAK2 and p-STAT3/STAT3, and the expression level of MMP-9 protein in knee cartilage tissue were significantly increased in the model group (P<0.01). In comparison with the model group, the Lequesne score, Mankin score, contents of serum IL-6, TNF-α and MMP-9, and the ratios of p-JAK2/JAK2 and p-STAT3/STAT3, and the expression of MMP-9 protein in knee cartilage tissue were notably decreased in both the warm acupuncture and medication groups (P<0.01,P<0.05). The levels of Lequesne score, Mankin score, contents of serum IL-6, TNF-α and MMP-9, and the ratios of p-JAK2/JAK2 and p-STAT3/STAT3 in knee cartilage tissue were significantly lower in the warm acupuncture group than in the medication group (P<0.01, P<0.05). No significant difference was found between the warm acupuncture and medication groups in the expression of MMP-9 protein (P>0.05). Outcomes of H.E. showed injury of the perichondrium of knee joint, obvious reduction of the cartilage matrix staining, cystic changes, clustered and disordered arrangement and severe pyknosis and necrosis of the surface cells with reduction of number of cells and increase of vacuoles in the model group, which was milder in both warm acupuncture and medication groups.

CONCLUSION

Warm acupuncture can improve motor function and reduce cartilage injury in KOA rabbits, which may be related to its functions in inhibiting the secretion of pro-inflammatory factors and regulating JAK2/STAT3 signaling and downregulating MMP-9 expression in the cartilage tissue.

CXCR1 participates in bone cancer pain induced by Walker 256 breast cancer cells in female rats

Bone cancer pain (BCP) is a clinically intractable mixed pain, involving inflammation and neuropathic pain, and its mechanisms remain unclear. CXC chemokine receptor 1 (CXCR1, IL-8RA) and 2 (CXCR2, IL-8RB) are high-affinity receptors for interleukin 8 (IL8). According to previous studies, CXCR2 plays a crucial role in BCP between astrocytes and neurons, while the role of CXCR1 remains unclear. The objective of this study was to investigate the role of CXCR1 in BCP. We found that CXCR1 expression increased in the spinal dorsal horn. Intrathecal injection of CXCR1 siRNA effectively attenuated mechanical allodynia and pain-related behaviors in rats. It was found that CXCR1 was predominantly co-localized with neurons. Intrathecal injection of CXCR1-siRNA reduced phosphorylated JAK2/STAT3 protein levels and the NLRP3 inflammasome (NLRP3, caspase1, and IL-1β) levels. Furthermore, in vitro cytological experiments confirmed this conclusion. The study results suggest that the spinal chemokine receptor CXCR1 activation mediates BCP through JAK2/STAT3 signaling pathway and NLRP3 inflammasome (NLRP3, caspase1, and IL-1β).

Viola yedoensis Makino formula alleviates DNCB-induced atopic dermatitis by activating JAK2/STAT3 signaling pathway and promoting M2 macrophages polarization

BACKGROUND

Atopic dermatitis (AD), a common inflammatory skin disorder, severely affects the life quality of patients and renders heavy financial burden on patient's family. The Chinese medicine Viola yedoensis Makino formula (VYAC) has been widely used for treating various skin disorders. Previous studies have reported that VYAC is effective in relieving DNCB-induced AD and inflammation. However, the anti-inflammatory mechanism of VYAC is still ill-defined and poorly understood. This study aims to investigate the therapeutic effects of VYAC on DNCB-induced AD and to elucidate the underlying anti-inflammatory mechanisms.

METHODOLOGY

VYAC were extracted with 70% ethanol and lyophilized for use. AD mice were established by DNCB. The therapeutic effects of VYAC were evaluated by oral administration VYAC (150, 300 and 600 mg/kg) daily in vivo. The histopathological and immunohistochemistry were used to analyze skin lesion and macrophages infiltration, RT-qPCR and Elisa were used to analyze the inflammatory factors in skin tissues and serum. To explore the underlying mechanism of VYAC against AD in vitro. RAW264.7 cells and bone-marrow-derived macrophages (BMDMs) were employed for macrophage polarization analysis. Flow cytometer, immunofluorescence and western blot were used to analyze M2 macrophages markers. STAT3 siRNA were transfected into both cells to validate the effects of VYAC-induced macrophages M2 polarization via JAK2/STAT3 signaling pathway.

RESULTS

VYAC ameliorated skin lesion of DNCB-induced AD mice by decreased clinical scores and epidermal thickness, decreased the level of pro-inflammatory factors (IL-1β, TNF-α and IL-18) and enhanced IL-10 anti-inflammatory factor level, inhibited macrophages infiltration and promoted M2 macrophages polarization in vivo. VYAC significantly promoted M2 macrophages polarization in vitro. It is observed that VYAC not only inhibited the phosphorylation of JAK2 and STAT3 in RAW264.7 cells and BMDMs, but also accelerated the translocation to the nucleus. What's more, VYAC reduced the polarization of M2 macrophage by activating JAK2/STAT3 signaling pathway was observed in both cells.

CONCLUSIONS

Our findings demonstrate that VYAC significantly ameliorates skin lesion of DNCB-induced AD mice and reduces the levels of inflammatory factors by activating JAK2/STAT3 signaling pathway and promoting M2 macrophages polarization.

MiR-630 suppresses non-small cell lung cancer by targeting vimentin

Objective

This study aimed to clarify the function of miR‐630 on non‐small cell lung cancer (NSCLC) cells.

Methods

Quantitative real‐time PCR was utilized to detect the mRNA expression of miR‐630 and vimentin (VIM) in NSCLC tissues and cells. The protein expression of VIM, P53, Caspase‐3, Bcl‐2, Bax and JAK2/STAT3 was evaluated via Western blot. Dual‐luciferase reporter assay was applied to evaluate whether VIM is the target gene of miR‐630. The migration, invasion, proliferation and apoptosis of NSCLC cells were examined by wound‐healing assay, transwell assay, CCK‐8 assay, and flow cytometry, respectively.

Results

MiR‐630 was lowly expressed in NSCLC tissues and cells, while VIM was highly expressed in NSCLC cells. Dual‐luciferase reporter assay data validated that miR‐630 directly targeted VIM. MiR‐630 overexpression inhibited VIM expression, but the inhibition of miR‐630 upregulated VIM expression. Besides, miR‐630 mimics restrained cell migration, invasion, and proliferation, and promoted NSCLC cell apoptosis. Whereas, VIM overexpression partly attenuated the inhibitory effect of miR‐630 on NSCLC cells. Moreover, miR‐630 mimics impeded p‐JAK2 and p‐STAT3 protein expression; and miR‐630 inhibitor upregulated p‐STAT3 and VIM protein expression, which was reversed after the addition of STAT3 inhibitor C188‐9.

Conclusion

MiR‐630 constrained the progression of NSCLC by inhibiting JAK2/STAT3 pathway and downregulating VIM expression.

LINC00893 inhibits the progression of prostate cancer through miR-3173-5p/SOCS3/JAK2/STAT3 pathway

Background

Prostate cancer (PCa) is one of the most common malignant tumors in the male urinary system. In recent years, the morbidity and mortality of PCa have been increasing due to the limited effects of existing treatment strategies. Long non-coding RNA (lncRNA) LINC00893 was reported to inhibit the proliferation and metastasis of papillary thyroid cancer cells, but its role in PCa has not been reported. This study aims to investigate the role and underlying mechanism of LINC00893 in regulating the progression of PCa cells.

Methods

We first compared LINC00893 expression levels between PCa tissues and normal prostate tissues through TCGA database. The relative LINC00893 expression levels were further validated in 66 pairs of PCa tissues and para-cancerous normal tissues, as well as in PCa cell lines. Gain-of-function experiment was performed by transfecting PCa cell with LINC00893 expression vector, and CCK (Cell count kit)-8, 5-Ethynyl-2′-deoxyuridine (EdU) incorporation, colony information and transwell assays were conducted to assess the functional phenotypes. Dual-luciferase reporter, RNA-binding protein immunoprecipitation (RIP) and RNA pull-down assays were performed to evaluate the molecular interactions.

Results

LINC00893 was downregulated in PCa tissues and cell lines, and patients with low expression of LINC00893 were associated with a poorer overall survival rate. LINC00893 overexpression hindered the proliferation, epithelial-mesenchymal transition (EMT) as well as the migratory ability of PCa cells, and suppressed the tumorigenesis of PCa cells in nude mice. We further demonstrated that LINC00893 acted as a sponge for miR-3173-5p and inhibited its activity, which in turn regulated the suppressor of cytokine signaling 3 (SOCS3)/Janus Kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling axis.

Conclusions

Our study demonstrated that LINC00893 suppresses the progression of PCa cells through targeting miR-3173-5p/SOCS3/JAK2/STAT3 axis. Our data uncovers a novel tumor-suppressor role of LINC00893 in PCa, which may serve as a potential strategy for targeted therapy in PCa.

Grapical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-022-02637-4.

RAR-Related Orphan Receptor: An Accelerated Preeclampsia Progression by Activating the JAK/STAT3 Pathway

PURPOSE

To investigate the effect and underlying mechanism of RAR related orphan receptor A (RORA) on preeclampsia (PE).

MATERIALS AND METHODS

Differentially expressed genes (DEGs) in four datasets were obtained by using the Venn diagram method. RORA mRNA and protein expressions were detected by qRT-PCR, western blot, and immunohistochemistry. HTR-8/SVneo cell viability, proliferation, invasion, migration, and angiogenesis were detected by CCK-8 assay, EdU assay, Transwell, wound healing assay, and tube formation assay, respectively. The concentration of Ang-1 in cells was assessed using available ELISA kit. Epithelial-mesenchymal transition, proliferation, and angiogenesis-related proteins were detected by western blot. GSEA analysis were performed for common DEGs, and the expression of enriched pathway-related proteins was also detected.

RESULTS

The expression of RORA was increased in PE tissue and HTR-8/SVneo cells. Silencing RORA could promote the migration, invasion, epithelial-mesenchymal transition, proliferation, and angiogenesis of hypoxia-treated HTR-8/SVneo cells. Mechanistically, RORA contributed to the deterioration of PE by activating the JAK2/STAT3 signaling pathway to promote cell proliferation, migration, invasion, and angiogenesis.

CONCLUSION

RORA was up-regulated in PE and affected HTR-8/SVneo cell proliferation, invasion, migration, apoptosis, and angiogenesis via the JAK2/STAT3 signaling pathway. This provided a novel strategy for the prevention and treatment of PE.

Magnolol alleviates hypoxia-induced pulmonary vascular remodeling through inhibition of phenotypic transformation in pulmonary arterial smooth muscle cells

Phenotypic transformation and excessive proliferation of pulmonary arterial smooth muscle cells (PASMCs) play an important role in vascular remodeling during pulmonary hypertension (PH). Magnolol (5,5'-diallyl-2,2'-dihydroxybiphenyl) is the major bioactive constituent isolated from the bark of Magnolia Officinalis, which has anti-inflammatory, antioxidant, and cardiovascular protection effects. However, the effect of magnolol on the phenotypic transformation of PASMCs is still unknown. This study aims to evaluate the effects of magnolol on the phenotypic transformation of PASMCs induced by hypoxia. In vivo, Sprague Dawley rats were exposed to hypoxia (10% O₂) for four weeks to establish a PH model. The results showed that hypoxia treatment led to an increase in right ventricle systolic pressure, Fulton index, collagen production, accompanied by upregulation in the expression of collagen Ⅰ, collagen Ⅲ, OPN, PCNA, CyclinD1, p-JAK2, and p-STAT3, as well as decreases in expression of SM-22α; these changes were attenuated by magnolol. In vitro, the primary cultured PASMCs were exposed to 3% O₂ for 48 h to induce phenotypic transformation. Consistent with the findings in vivo, magnolol treatment could prevent the phenotypic transformation and hyperproliferation of PASMCs induced by hypoxia, accompanied by downregulation in the expression of p-JAK2 and p-STAT3. In summary, this study demonstrated that the protective effect of magnolol on PH vascular remodeling is related to the inhibition of phenotypic transformation and hyperproliferation of PASMCs by inhibiting the JAK2/STAT3 pathway.

Formononetin protects against inflammation associated with cerebral ischemia-reperfusion injury in rats by targeting the JAK2/STAT3 signaling pathway

BACKGROUND

Formononetin is a type of phytoestrogen obtained from the Chinese medical herb Red Clover. It exhibits anti-neoplastic hepatoprotective, and neuroprotective properties. However, the anti-inflammatory effect of formononetin in cerebral ischemia-reperfusion injury has not been reported.

OBJECTIVE

To explore the potential mechanism of action of formononetin in cerebral ischemia-reperfusion injury with regard to the JAK2/STAT3 signaling pathway.

METHODS

Male SD rats were used to establish a middle cerebral artery occlusion (MCAO) model and randomly divided into 5 groups: Sham, MCAO, JAK2 Inhibitor (Ag490), Formononetin, Inhibitor + Formononetin. The protective effect of formononetin in MCAO rats was detected by performing neurological deficit testing, TTC staining, H&E staining, Nissl staining, ELISA, RT-PCR, western blotting and immunofluorescence.

RESULTS

Formononetin significantly alleviated the neurological deficit and the pathological state of brain tissues, and reduced the volume of cerebral infarction, levels of IL-18 and TNF-α inflammatory factors in plasma, mRNA levels of IL-6 and IL-1β in rat brain tissue, and the protein levels of p-JAK2, p-STAT3, NLRP3, ASC, cl-Caspase-1, and cl-IL-1β in the MCAO rat brain tissue.

CONCLUSION

Formononetin has anti-inflammatory effects. It may inhibit the relevant targets in the JAK2/STAT3 signaling pathway, thereby having a certain protective effect against cerebral ischemia-reperfusion injury.

The role of exosomal miR-181b in the crosstalk between NSCLC cells and tumor-associated macrophages

BACKGROUND

It has been reported that tumor-associated macrophages (TAMs) participate in modulating the progression of cancer in the tumor microenvironment. However, the crosstalk between TAMs and non-small cell lung cancer (NSCLC) is still unclear.

OBJECTIVE

We investigated whether NSCLC-derived exosomes could affect TAMs, which feedback modulated progression of NSCLC.

METHODS

MiR-181b expression was measured by RT-PCR. Human THP-1 monocyte was differentiated into macrophages with phorbol myristate acetate, which were further identified by transmission electron microscopy and western blot. Macrophage M1 and M2 polarizations were detected by flow cytometry, RT-PCR and western blot. Proliferation, migration, and invasion of NSCLC cells treated with conditioned mediums were detected by EdU and Transwell assays.

RESULTS

We demonstrated that miR-181b was up-regulated in exosomes derived from NSCLC patients' serum and NSCLC cells. MiR-181b could be transferred to macrophages via exosomes in the co-culture system of macrophages and NSCLC cells, which promoted macrophage M2 polarization. Further examinations revealed that exosomes derived from NSCLC cells could enhanced macrophage M2 polarizations by regulating miR-181b/JAK2/STAT3 axis, and silencing miR-181b in NSCLC cells and JAK2 inhibitor used in macrophages could reverse the effects. Importantly, the conditioned medium of macrophages treated with NSCLC cell-derived exosomes could promote NSCLC cell proliferation, migration, and invasion. Silencing miR-181b in NSCLC cells and JAK2 inhibitor used in macrophages could block the effects.

CONCLUSIONS

All of these results indicated that exosomal miR-181b participated in the crosstalk between NSCLC cells and TAMs, providing potential therapeutic targets for NSCLC.

Polydatin down-regulates the phosphorylation level of STAT3 and induces pyroptosis in triple-negative breast cancer mice with a high-fat diet

Background

To explore the impact of polydatin on mice with triple-negative breast cancer (TNBC) receiving a high-fat diet, as well as the underlying processes.

Methods

A total of 40 female Balb/c mice were randomly separated into 4 groups (4T1 + polydatin + fat diet group, 4T1 + high-fat diet group, 4T1 + polydatin group, and 4T1 group). To establish the obese TNBC mouse model, TNBC was xenografted 1×10⁵ 4T1 cells/50 µL per mouse at the right fourth mammary fat pad under anesthesia and the mice were fed a high fat diet. When the experiment was completed, total plasma cholesterol (TC) and cancer antigen (CA)15-3 were measured. The enzyme-linked immunosorbent assay (ELISA) method was used detect CA15-3. Oil red O staining was used to observe the morphological changes. Western blot analysis and reverse transcription polymerase chain reaction (RT-PCR) were used to detect the corresponding protein expression and the messenger RNA (mRNA) level.

Results

Polydatin decreased the degree of fatty liver, as determined by oil red O staining. The TC level in the 4T1 + fat diet group was significantly higher, and it was decreased in the 4T1 + polydatin group. The results of ELISA showed that compared with the 4T1 group, CA15-3 was significantly increased in the 4T1 + fat diet group, and polydatin was shown to significantly reduce the expression of CA15-3. Polydatin inhibited p-JAK2 and p-STAT3 mRNA and protein levels. Polydatin increased pyroptosis-related gene mRNA and protein level.

Conclusions

We believe that polydatin can effectively reduce blood lipid levels in TNBC mice with a high-fat diet, and play an anticancer role in TNBC. The underlying mechanism may be related to the JAK2/STAT3 signaling pathway and pyroptosis in TNBC. Our results contribute to validating the traditional use of polydatin in the treatment of TNBC with hyperlipidemia.

Yi Shen Juan Bi Pill Regulates the Bone Immune Microenvironment via the JAK2/STAT3 Signaling Pathway in Vitro

Rheumatoid arthritis (RA) is characterized by an impaired articular bone immune microenvironment, which is associated with regulatory T cells (Tregs) hypofunction and osteoclasts (OCs) hyperfunction and leads to articular bone erosion and systemic bone loss. Studies have shown that Tregs slow bone loss in RA by regulating the bone resorption function of OCs and the JAK/STAT signaling pathway can regulate the immunosuppressive function of Tregs and reduce the bone erosion function of OCs. Yi Shen Juan Bi Pill (YSJB) is a classic Chinese herbal compound for the treatment of RA. However, whether YSJB regulates bone immune microenvironment homeostasis through JAK/STAT signaling pathway remains unclear. Based on in vitro OC single culture, Treg single culture and OC-Treg coculture systems, treatments were performed using drug-containing serum, AG490 and JAK2 siRNA to explore whether YSJB-containing serum regulates the homeostasis of the bone immune microenvironment through the JAK/STAT signaling pathway. In vitro, YSJB treatment decreased the number of TRAP⁺ cells and the areas of bone resorption and inhibited the expression of RANK, NFATc1, c-fos, JAK2, and STAT3 in both the OC single culture system and the OC-Treg coculture system. Tregs further reduced the number of TRAP⁺ cells and the areas of bone resorption in the coculture system. YSJB promoted the secretion of IL-10 while inhibiting the expression of JAK2 and STAT3 in Tregs. Moreover, inhibiting the expression of JAK2 with the JAK2 inhibitor AG490 and JAK2 siRNA improved the immunosuppressive functions of Treg, inhibited OC differentiation and bone resorption. Our study demonstrates that YSJB can regulate OC-mediated bone resorption and Treg-mediated bone immunity through the JAK2/STAT3 signaling pathway. This study provides a new strategy for regulating the bone immune microenvironment in RA with traditional Chinese medicine.

PM2.5 promoted lipid accumulation in macrophage via inhibiting JAK2/STAT3 signaling pathways and aggravating the inflammatory reaction

BACKGROUND

Abnormal lipid accumulation in macrophages may lead to macrophages foaming, which is the most important pathological process of atherosclerosis. Atmospheric PM_2.5 could enter the blood circulation and further affect the lipid metabolism of macrophages. But the underlying mechanism is not unclear. This study was undertaken to clarify the effect of PM_2.5 on lipid metabolism in macrophages, and to explore the role of inflammatory reaction and JAK2/STAT3 signaling pathway in this process.

METHOD

Macrophages derived from THP-1 cells were exposed to PM_2.5 (0,100,200,400 μg/mL) for 6 h and 12 h. STAT3 agonist ColivelinTFA is used to specifically excite STAT3. The survival rate of macrophages was detected by CCK-8. The lipid levels in macrophages were detected by colorimetry. The levels of inflammatory factors secreted by macrophages were detected by ELISA. Q-PCR was used to detect the mRNA expression levels, and Western Blot was used to detect the protein expression levels of JAK2/STAT3 pathway genes.

RESULT

The survival rate of macrophages was reduced by PM_2.5, and the levels of TG, T-CHO and LDL-C of macrophages exposed to PM_2.5 were increased. PM_2.5 led to the increasing level of IL-6 and the decreasing level of IL-4, and the JAK2/STAT3 signaling pathway was inhibited by PM_2.5. Colivelin TFA significantly decreased the increasing levels of TG, T-CHO and LDL-C levels, and increased the decreasing mRNA levels of IL-4, and LPL induced by PM_2.5 (p < 0.05).

DISCUSSION

PM_2.5 could cause the lipid accumulation of macrophages by inhibiting the JAK2/STAT3 signaling pathway, and inflammatory responses may be involved in this process.

Upregulation of miR-216a-5p by Lentinan Targeted Inhibition of JAK2/STAT3 Signaling Pathway to Reduce Lung Adenocarcinoma Cell Stemness, Promote Apoptosis, and Slow Down the Lung Adenocarcinoma Mechanisms

To investigate the effect of Lentinan (LNT) on lung adenocarcinoma (LUAD) cell stemness and its mechanism. In this study, we founded that LNT significantly reduce the cell proliferation, activity, migration, invasion, and stemness of LUAD cells, and promote their apoptosis compared with the control group in vitro. Moreover, LNT significantly inhibited the volume and weight of tumors of nude mice in vivo. At the same time, LNT can significantly up-regulate miR-216a-5p levels and reduce the protein expression of phospho-JAK2 (Y1007/1008) and phospho-STAT3 (Tyr705), thereby inhibiting the JAK2/STAT3 signaling pathway. Interfering with miR-216a-5p expression and activating the JAK2/STAT3 signaling pathway can significantly reverse LNT inhibitory effects on LUAD. Collectively, LNT can inhibit the JAK2/STAT3 signaling pathway by up-regulating miR-216a-5p, reducing stemness, and promoting LUAD cells apoptosis, then slow down LUAD occurrence and development, providing concepts and experimental foundation treating patients with LUAD.

Berberrubine attenuates potassium oxonate- and hypoxanthine-induced hyperuricemia by regulating urate transporters and JAK2/STAT3 signaling pathway

Phellodendri Chinensis Cortex (PC) is a traditional medicinal material used to treat gout and hyperuricemia (HUA) in China. Berberine (BBR), the main component of PC, possesses anti-hyperuricemic and anti-gout effects. However, BBR exhibits low bioavailability due to its extensive metabolism and limited absorption. Thus, the metabolites of BBR are believed to be the potential active forms responsible for its in vivo biological activities. Berberrubine (BRB), one of the major metabolites of BBR, exhibits appreciable biological activities even superior to BBR. In this work, the anti-hyperuricemic efficacy of BRB was investigated in HUA model mice induced by co-administration with intraperitoneal potassium oxonate (PO) and oral hypoxanthine (HX) for 7 days. Results showed that administration with BRB (6.25, 12.5, and 25.0 mg/kg) significantly decreased the serum levels of uric acid (UA) by 49.70%, 75.35%, and 75.96% respectively, when compared to the HUA group. In addition, BRB sharply decreased the levels of blood urea nitrogen (BUN) (by 19.62%, 28.98%, and 38.72%, respectively) and serum creatinine (CRE) (by 16.19%, 25.07%, and 52.08%, respectively) and reversed the PO/HX-induced renal histopathological damage dose-dependently. Additionally, BRB lowered the hepatic XOD activity, downregulated the expressions of glucose transporter 9 (GLUT9) and urate transporter 1 (URAT1), upregulated expressions of organic anion transporter 1/3 (OAT1/3) and ATP-binding cassette transporter subfamily G member 2 (ABCG2) at both protein and mRNA levels, and suppressed the activation of the JAK2/STAT3 signaling pathway. In addition, BRB significantly decreased the levels of inflammatory mediators (IL-1β, IL-6, and TNF-α). In conclusion, our study indicated that BRB exerted anti-hyperuricemic effect, at least in part, via regulating the urate transporter expressions and suppressing the JAK2/STAT3 signaling pathway. BRB was believed to be promising for further development into a potential therapeutic agent for HUA treatment.

Urantide alleviates the symptoms of atherosclerotic rats in vivo and in vitro models through the JAK2/STAT3 signaling pathway

Atherosclerosis is the leading cause of human death, and its occurrence and development are related to the urotensin II (UII) and UII receptor (UT) system and the biological function of vascular smooth muscle cells (VSMCs). During atherosclerosis, impaired biological function VSMCs may promote atherosclerotic plaque formation. The Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) pathway is an important mediator of signal transduction; however, the role of this signaling pathway in atherosclerosis and VSMCs remains unknown. This study aimed to investigate the effects of urantide on the JAK2/STAT3 signaling pathway in atherosclerosis. We examined the effect of urantide on the UII/UT system and the JAK2/STAT3 signaling pathway in a high fat diet induced atherosclerosis rat model and studied the effect and mechanism of urantide on the phenotypic transformation of VSMCs. We found that the UII/UT system and JAK2/STAT3 signaling pathway were highly activated in the thoracic aorta in atherosclerotic rats and in ox-LDL- and UII-induced VSMCs. After urantide treatment, the pathological changes in atherosclerotic rats were effectively improved, and the activities of the UII/UT system and JAK2/STAT3 signaling pathway were inhibited. Moreover, urantide effectively inhibited proliferation and migration and reversed the phenotypic transformation of VSMCs. These results demonstrated that urantide may control the JAK2/STAT3 signaling pathway by antagonizing the UII/UT system, thereby maintaining the biological function of VSMCs and potentially preventing and curing atherosclerosis.

MiR-135-5p Alleviates Bone Cancer Pain by Regulating Astrocyte-Mediated Neuroinflammation in Spinal Cord through JAK2/STAT3 Signaling Pathway

Bone cancer pain (BCP) was associated with microRNA dysregulation. In this study, we intended to clarify the potential role of miR-135-5p in a BCP mouse model, which was established by tumor cell implantation (TCI) in the medullary cavity of the mouse femur. The BCP-related behaviors were tested, including the paw withdrawal mechanical threshold (PWMT) and number of spontaneous flinches (NSF). The miRNA expression profiles in astrocytes of the sham and tumor groups were compared, and miRNA microarray and quantitative real-time PCR (qRT-PCR) assays confirmed that the amount of expression of miR-135-5p was significantly decreased in astrocytes of the tumor group. Gain- and loss-of-function studies showed that miR-135-5p could inhibit astrocyte activation and inflammation cytokine (TNF-α and IL-1β) expression. The relation between miR-135-5p and JAK2 was detected by bioinformatic analysis and dual luciferase reporter gene assay. By conducting in vitro experiments, it was shown that the miR-135-5P mimics lowered the level of JAK2/STAT3 proteins and inflammatory factors in astrocytes. Moreover, in vivo analysis on BCP mice model indicated that the miR-135-5p agonist could sufficiently increase PWMT and decrease NSF. Meanwhile, reduced activation of astrocytes in the spinal cord, as well as decreased expression of JAK2/STAT3 and inflammatory mediators, were found after miR-135-5p agonist treatment. Collectively, the results showed that miR-135-5p could potentially reduce BCP in mice through inhibiting astrocyte-mediated neuroinflammation and blocking of the JAK2/STAT3 signaling pathway, indicating that the upregulation of miR-135-5P could be a therapeutic focus in BCP treatment.

Correlation of IL-6 and JAK2/STAT3 signaling pathway with prognosis of nasopharyngeal carcinoma patients

IL-6 is reported to be the main upstream activator, instead of the downstream target of JAK2/STAT3. This study is intended to explore the correlation of IL-6 and JAK2/STAT3 signaling pathway with clinicopathological features and prognosis in nasopharyngeal carcinoma (NPC). First, NPC tissues and normal nasopharyngeal epithelial tissues were obtained from 117 NPC patients. Next, we detected expression levels of IL-6 in serum and those of STAT3, p-STAT3, JAK2, p-JAK2 and CyclinD1 in tissues. A follow-up was conducted in all the patients and the survival was analyzed. To verify the correlation of IL-6 and JAK2/STAT3 pathway, CNE-1 and SUNE1 NPC cells were interpreted with IL-6 and JAK2/STAT3 signaling pathway inhibitor AG490 to detect cell viability, migration and invasion. We observed thatIL-6 increased in serum of NPC patients. The expressions of IL-6, STAT3, p-STAT3, JAK2, p-JAK2 and CyclinD1 in NPC tissues were higher and correlated with TNM stage and lymph node metastasis (LNM). Survival rates were reduced in patients with positive expressions of IL-6, STAT3, p-STAT3, JAK2, p-JAK2 and CyclinD1. LNM and positive expressions of IL-6 and p-STAT3 were risk factors for poor prognosis of NPC. Besides, recombinant human IL-6 promoted cell proliferation, invasion and migration while AG490 inhibited cell proliferation, invasion and migration in CNE-1 and SUNE1 NPC cells. The results demonstrated that increased IL-6 expression and the activated JAK2/STAT3 signaling pathway had effects on prognosis and reduced the survival time in NPC patients, which provide a potential target for the treatment of NPC.

Tibetan medicine Ershiwuwei Lvxue Pill attenuates collagen-induced arthritis via inhibition of JAK2/STAT3 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Ershiwuwei Lvxue Pill (ELP, མགྲིན་མཚལ་ཉེར་ལྔ།), a traditional Tibetan medicine preparation, has been used hundreds of years for the clinical treatment of rheumatoid arthritis (RA) in the highland region of Tibet, China. However, the underlying mechanism of its therapeutic effect remains unclear.

AIM OF THE STUDY

The present study aimed to investigate the potential pharmacological mechanisms of anti-arthritic effect of ELP.

MATERIALS AND METHODS

The main chemical constituents of ELP were analyzed by ultra-performance liquid chromatography quadrupole-time-flight mass spectrometry (UPLC-Q-TOF-MS). Forty-eight male Wistar rats (220 ± 20 g) were randomly divided into six groups: normal group, collagen-induced arthritis (CIA) group, methotrexate group (1.05 mg/kg), ELP groups (115, 230 and 460 mg/kg). CIA rat models were assigned to evaluate the anti-RA activity of ELP by determining the paws swelling, arthritis score, organ coefficients of spleen and thymus, and histopathological analysis of knee joints of synovial tissues. The levels of TNF-α, IL-10, IL-6 and IL-17 in serum were measured by ELISA. In addition, mRNA and protein expression levels associated with JAK2/STAT3 signaling pathway in synovial tissues of CIA rats were detected by qRT-PCR, immunohistochemistry and Western blot analyses.

RESULTS

Fourteen main chemical constituents of ELP were quantitatively determined by UPLC-Q-TOF-MS analysis. Treatment with ELP reduced the paw swelling, arthritis score and organ coefficients of spleen and thymus. Histopathological examination revealed the protective effects of ELP on CIA rats with knee joint injury. The levels of serum pro-inflammatory cytokines (TNF-α, IL-6 and IL-17) were markedly reduced while the anti-inflammatory cytokine IL-10 was significantly increased with the treatment of ELP. Further investigations showed ELP down-regulated the mRNA and protein expression levels of Bcl-2, whereas up-regulated Bax, SOCS1 and SOCS3. Meanwhile, the ratios of p-JAK2/JAK2 and p-STAT3/STAT3 proteins from synovial tissues were dramatically decreased with the treatment of ELP, whereas no changes of the mRNA and protein expression levels of JAK2 and STAT3 were observed.

CONCLUSION

These results indicated that ELP reduced the severity of arthritis and joint swelling, suggesting an antirheumatic effect on CIA rats. The possible mechanism is related to inhibiting inflammatory response and inducing apoptosis in synovial tissues by regulating JAK2/STAT3 signaling pathway. However, further in vivo and in vitro investigations are still needed to clarify the underlying mechanism of ELP in treating RA.

Elevated retinol binding protein 4 levels are associated with atherosclerosis in diabetic rats via JAK2/STAT3 signaling pathway

BACKGROUND

Atherosclerosis is a major cause of mortality worldwide and is driven by multiple risk factors, including diabetes, which results in an increased atherosclerotic burden, but the precise mechanisms for the occurrence and development of diabetic atherosclerosis have not been fully elucidated.

AIM

To summarize the potential role of retinol binding protein 4 (RBP4) in the pathogenesis of diabetic atherosclerosis, particularly in relation to the RBP4-Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) signaling pathway.

METHODS

Male Wistar rats were randomly divided into three groups, including a control group (NC group), diabetic rat group (DM group), and diabetic atherosclerotic rat group (DA group). The contents of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), triglycerides (TG), low-density lipoprotein cholesterol (LDL-c), fasting insulin (FINS), fasting plasma glucose, and hemoglobin A1c (HbA1c) were measured. Moreover, the adipose and serum levels of RBP4, along with the expression levels of JAK2, phosphorylated JAK2 (p-JAK2), STAT3, phosphorylated STAT3 (p-STAT3), B-cell lymphoma-2 (Bcl-2), and Cyclin D1 in aortic tissues were also measured. Besides, homeostasis model assessment of insulin resistance (HOMA-IR) and atherogenic indexes (AI) were calculated.

RESULTS

Compared with the NC and DM groups, the levels LDL-c, TG, TC, FINS, HOMA-IR, RBP4, and AI were upregulated, whereas that of HDL-c was downregulated in the DA group (P < 0.05); the mRNA levels of JAK2, STAT3, Cyclin D1, and Bcl-2 in the DA group were significantly increased compared with the NC group and the DM group; P-JAK2, p-JAK2/JAK2 ratio, p-STAT3, p-STAT3/STAT3 ratio, Cyclin D1, and Bcl-2 at protein levels were significantly upregulated in the DA group compared with the NC group and DM group. In addition, as shown by Pearson analysis, serum RBP4 had a positive correlation with TG, TC, LDL-c, FINS, HbA1C, p-JAK2, p-STAT3, Bcl-2, Cyclin D1, AI, and HOMA-IR but a negative correlation with HDL-c. In addition, multivariable logistic regression analysis showed that serum RBP4, p-JAK2, p-STAT3, and LDL-c were predictors of the presence of diabetic atherosclerosis.

CONCLUSION

RBP4 could be involved in the initiation or progression of diabetic atherosclerosis by regulating the JAK2/STAT3 signaling pathway.

Anti-arthritic Effect of the Spirocyclopiperazinium Salt Compound LXM-15 in Rats and Its Underlying Mechanism

In this study, we aimed to evaluate the effects of the spirocyclopiperazinium salt compound LXM-15 on rheumatoid arthritis induced by complete Freund's adjuvant (CFA) in rats and investigate the underlying mechanism. The results showed that LXM-15 significantly inhibited the paw edema and ankle swelling, and alleviated the mechanical allodynia and thermal hyperalgesia responses in the CFA rats. The histopathological results revealed that LXM-15 ameliorated the infiltration of inflammatory cells and joint destruction. The micro-CT scan showed that LXM-15 alleviated bone erosion and increased BMD in the ankle joints of the CFA rats. Western blot analyses showed that LXM-15 significantly reduced the upregulation of phospho-JAK2, phospho-STAT3, phospho-IκBα, and phospho-NF-κBp65, and the overexpression of BDNF in the dorsal root ganglions. ELISA result showed that the protein level of TNF-α in the paw tissue was decreased upon LXM-15 treatment. RT-PCR analysis showed that the mRNA expression levels of c-fos and BDNF were reduced in the dorsal root ganglions by LXM-15 treatment. The LXM-15-mediated anti-arthritic effects were abolished by treatment with hexamethonium (a peripheral nicotinic receptor antagonist), atropine methylnitrate (a peripheral muscarinic receptor antagonist), methyllycaconitine citrate (a selective α7 nicotinic receptor antagonist), and tropicamide (a selective M4 muscarinic receptor antagonist). Collectively, our results demonstrate that LXM-15 exerts anti-arthritic effects in CFA rats. The underlying mechanism may be related to the activation of the peripheral α7 nicotinic receptor and M4 muscarinic receptor by LXM-15, further suppressing the activation of the JAK2/STAT3 and IκBα/NF-κBp65 signaling pathways and, eventually, inhibiting the expression levels of TNF-α, BDNF, and c-fos.

Neuritin inhibits astrogliosis to ameliorate diabetic cognitive dysfunction

Earlier, it was shown that reversing the downregulation of neuritin expression in the brain improves central neuropathy in diabetic rats. We investigated the protective mechanism of neuritin in diabetic cognitive dysfunction via astrocytes. Further, the impact of the overexpression of neuritin in the cortex and the hippocampus on diabetic cognitive dysfunction and astrogliosis in type 2 diabetic (db/db) mice was assessed. Antagonists were used to inhibit the JAK2/STAT3 signaling pathway in U-118MG, an astrocyte cell line. Immunofluorescence, Western blotting, and real-time PCR were performed. Neuritin overexpression in the hippocampus of db/db mice significantly ameliorated cognitive dysfunction, hippocampal neuronal impairment, and synaptic plasticity deterioration, and inhibited astrogliosis and the JAK2/STAT3 signaling pathway in the hippocampus. Neuritin suppressed the JAK2/STAT3 signaling pathway to inhibit lipopolysaccharide-induced gliosis in U-118MG cells. It was observed that neuritin regulates the JAK2/STAT3 signaling pathway in astrocytes to inhibit astrogliosis and improve diabetic cognitive dysfunction.

Electroacupuncture ameliorates intestinal inflammation by activating α7nAChR-mediated JAK2/STAT3 signaling pathway in postoperative ileus

Inflammatory cytokines produced by muscularis macrophages largely contribute to the pathological signs of postoperative ileus (POI). Electroacupuncture (EA) can suppress inflammation, mainly or partly via activation of vagal efferent. The goal of this study was to investigate the mechanisms by which EA stimulation at an hindlimb region ameliorates inflammation in POI.

Methods: Intestinal motility and inflammation were examined after 24 h after intestinal manipulation (IM)-induced POI in mice. Local immune response in the intestinal muscularis, expression of macrophages, α7 nicotinic acetylcholine receptor (α7nAChR), Janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3) were determined by flow cytometry, Western Blot, qPCR and immunofluorescence. The effects of α7nAChR antagonists (methyllycaconitine and α-bungarotoxin) and JAK2/STAT3 inhibitors (AG490 and WP1066) were also administered in a subset of mice prior to EA. In the parasympathetic pathways, intestinal motility and inflammation were determined after cervical vagotomy and sub-diaphragmatic vagotomy. The expression of gamma absorptiometry aminobutyric acid (GABA_A) receptor in dorsal motor nucleus of vagal (DMV) cholinergic neurons was assessed by immunofluorescence and the response to DMV microinjection of bicuculine (antagonist of GABA_A receptor) or muscimol (agonist of GABA_A receptor) were assessed.

Results: EA suppressed intestinal inflammation and promoted gastrointestinal motility. Mechanistically, EA activated the α7nAChR-mediated JAK2/STAT3 signaling pathway in macrophages which reduced the production of inflammatory cytokines. Furthermore, we also demonstrated that hindlimb region stimulation drove vagal efferent output by inhibiting the expression of GABA_A receptor in DMV to ameliorate inflammation.

Conclusions: The present study revealed that EA of hindlimb regions inhibited the expression of GABA_A receptor in DMV neurons, whose excited vagal nerve, in turn suppressed IM-induced inflammation via activation of α7nAChR-mediated JAK2/STAT3 signaling pathway.

Downregulation of miR-19a inhibits the proliferation and promotes the apoptosis of osteosarcoma cells by regulating the JAK2/STAT3 pathway

Osteosarcoma is a malignant tumor derived from the skeletal system, often occurring in bone tissues, and it is the most common malignant tumor in the skeletal system, with more than 90% of cases being highly malignant. The present study was designed to explore the regulatory effects of microRNA (miR)-19a on the proliferation and apoptosis of osteosarcoma cells, and its influence on the activation of the Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway. The expression of miR-19a in adult SaOS-2 osteosarcoma cells was downregulated via lentiviral transfection, and the cells were divided into a control group, NC-inhibitor group and miR-19a-inhibitor group. The expression of miR-19a in each group was detected via quantitative polymerase Chain reaction (qPCR). Next, the cell proliferation and apoptosis levels in each group were detected via methyl thiazolyl tetrazolium (MTT) assay and flow cytometry, respectively, and the level of reactive oxygen species (ROS) in cells was further determined. Moreover, the expression levels of apoptosis-related proteins and JAK2/STAT3 signaling pathway-related proteins were detected through western blotting. The expression level of miR-19a in the miR-19a-inhibitor group was significantly lower than that in the control group and NC-inhibitor group (P<0.01). Downregulation of miR-19a significantly reduced the proliferation ability (P<0.01), increased the apoptosis level of SaOS-2 cells (P<0.01), and significantly increased the ROS level in cells (P<0.01). Downregulation of miR-19a also promote cleaved caspase-3/caspase-3 expression in the OS cells (P<0.01) and inhibited Bcl-2/Bax expression (P<0.01). Additionally, downregulation of miR-19a markedly lowered the protein expression levels of phosphorylated (p-)JAK2, p-STAT3 and myeloid cell leukemia-1 (Mcl-1) in the cells (P<0.01). To conclude, downregulation of miR-19a can inhibit the JAK2/STAT3 signaling pathway in SaOS-2 cells, promote the expression of apoptosis-related proteins, and increase the ROS level in cells, thereby promoting apoptosis and inhibiting cell proliferation.

Ruxolitinib attenuates intimal hyperplasia via inhibiting JAK2/STAT3 signaling pathway activation induced by PDGF-BB in vascular smooth muscle cells

BACKGROUND

Cardiovascular diseases are associated with proliferation and phenotypic switch. Platelet-derived growth factor-BB (PDGF-BB) is a major initiating factor for proliferative vascular diseases, such as neointimal lesion formation, restenosis after angioplasty, and atherosclerosis. Ruxolitinib, a potent Janus kinase (JAK) 1 and 2 inhibitor, has been reported to significantly block the proliferation-related signaling pathway of JAK2/signal transducers and activators of transcription 3 (STAT3) and harbor a broad spectrum of anti-cancer activities, including proliferation inhibition, apoptosis induction, and anti-inflammation. However, the role of ruxolitinib in regulating PDGF-BB-induced VSMC proliferation remains to be elucidated. Thus, this study investigates the role of ruxolitinib in regulating PDGF-BB-induced VSMC proliferation and its underlying mechanisms.

METHODS

In vivo, the medial thickness of the carotid artery was evaluated using a mouse carotid ligation model, ruxolitinib was administered orally to the mice every other day, and the mice were euthanized on day 28 to evaluate the therapeutic effects of ruxolitinib. Cell proliferation markers were measured using real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blotting. In vitro, VSMCs were treated with ruxolitinib with or without PDGF-BB at an indicated time and concentration. Cell proliferation and apoptosis were measured using Cell Counting Kit-8 assay, MTS assays and flow cytometry. The JAK2/STAT3 signaling pathway involved in the effects of ruxolitinib on VSMCs was detected by western blotting with the specific pathway inhibitor AG490.

RESULTS

In vivo, ruxolitinib significantly decreased the ratio-of-intima ratio (I/M ratio) by inhibiting the expression of PCNA and cyclinD1 (p <0.05). In vitro, ruxolitinib inhibited PDGF-BB-induced VSMC proliferation compared with the PDGF-BB treatment group (p <0.05). In addition, ruxolitinib inhibited the PDGF-BB-induced activation of the JAK2/STAT3 signaling pathway and decreased the expression of proliferation related-proteins cyclinD1 and PCNA in VSMCs (p <0.05).

CONCLUSION

Our findings suggest that ruxolitinib inhibits VSMC proliferation in vivo and in vitro by suppressing the activation of the JAK2/STAT3 signaling pathway. Therefore, ruxolitinib has a therapeutic potential for proliferative vascular diseases.

Ulinastatin attenuates monocyte-endothelial adhesion via inhibiting ROS transfer between the neighboring vascular endothelial cells mediated by Cx43

Ulinastatin is widely used in the treatment of pancreatitis and sepsis, because of its excellent anti-inflammatory and antioxidant effects. However, its effects on atherosclerosis, an inflammatory vascular disease, are rarely reported. Therefore, in present study, we explored effects of ulinastatin on monocyte-endothelial adhesion, the initiator of atherosclerosis. We used U937 monocytes and angiotensin II-stimulated human umbilical vein endothelial cells (HUVECs) to build the model of monocyte-endothelial adhesion. Different methods were used to change the function of connexin43 (Cx43), the level of ROS, the activation of JAK2/STAT3 signaling pathway and its downstream MMP2 and MMP9 expression, and then the influences of ulinastatin on U937-HUVECs adhesion and the adhesion molecules were observed. The results showed that ulinastatin could attenuate ROS transmission between the neighboring HUVECs via inhibiting Cx43 function. With the decrease of ROS, JAK2/STAT3 signaling pathway and its downstream MMP2 and MMP9 expression were downregulated. Ultimately, important adhesion molecules expression, such as VCAM-1, ICAM-1, sVCAM-1 and sICAM-1, and U937-HUVECs adhesion, were both reduced. Thus, we can conclude that ulinastatin attenuates adhesion molecules expression and monocyte-endothelial adhesion, mechanism of which is related that ulinastatin inhibits ROS transfer between the neighboring vascular endothelial cells mediated by Cx43, resulting in the inactivation of JAK2/STAT3 signaling pathway, and its downstream MMP2 and MMP9 expression decrease.

Effect of matrine on JAK2/STAT3 signaling pathway and brain protection in rats with cerebral ischemia-reperfusion

BACKGROUND

Ischemic encephalopathy is a common clinical disease. The main treatment goal is to achieve vascular recanalization. However, after vascular recanalization, the reperfusion of fresh blood can change local cell metabolism, thus adversely affecting cell structure and function, which can result in reperfusion injury.

OBJECTIVES

To explore the effect of matrine intervention of different concentrations on JAK2/STAT3 signaling pathway and brain protection in rats with cerebral ischemia-reperfusion.

MATERIAL AND METHODS

Healthy male Sprague Dawley rats were divided into a blank control group (20 rats), a model group (80 rats) and a sham group (20 rats). In the model group, the middle cerebral artery was occluded with suture method to establish cerebral ischemia-reperfusion model rats, which were subdivided into cerebral ischemia-reperfusion group, and 5, 10 and 20 mg/kg matrine groups, with 20 rats in each group. Indicators including neurological function score, brain infarct size, brain water content, lactic dehydrogenase activity, protein expressions of p-JAK2 and p-STAT3, as well as superoxide dismutase activity and malondialdehyde content were evaluated.

RESULTS

Compared with cerebral ischemia-reperfusion group, all the indicators were significantly improved in the 3 matrine treatment groups in a dose-dependent manner, and protein expressions of p-JAK2 and p-STAT3 in the brain tissue and brain cell apoptosis rate were decreased with the increase of matrine concentration (all p < 0.05).

CONCLUSIONS

Matrine can significantly ameliorate the neurological function and brain edema of rats with cerebral ischemia-reperfusion, and improve superoxide dismutase, malondialdehyde and lactic dehydrogenase levels in the brain tissue and brain cell apoptosis rate. The mechanism of matrine may be related to the inhibition of abnormal JAK2/STAT3 signaling pathway activation.

Neuroprotective Effect of Mesenchymal Stromal Cell-Derived Extracellular Vesicles Against Cerebral Ischemia-Reperfusion-Induced Neural Functional Injury: A Pivotal Role for AMPK and JAK2/STAT3/NF-κB Signaling Pathway Modulation

Introduction

Cerebral ischemia-reperfusion injury (CIRI) is the main factor that leads to poor prognosis of cerebral ischemia. Apoptosis has been shown to occur during the process of CIRI. Extracellular vesicles derived from mesenchymal stromal cells (MSCs-EVs) have shown broad potential for treating brain dysfunction and eliciting neuroprotective effects after stroke through neurogenesis and angiogenesis. However, the mechanism of action of extracellular vesicles during CIRI is not well known.

Methods

A middle cerebral artery occlusion (MCAO) model was induced by the modified Longa method, and MSCs-EVs were injected via the tail vein.

Results

Our results showed that MSCs-EVs significantly alleviated neurological deficits, reduced the volume of cerebral infarction and brain water content, improved pathological lesions in cortical brain tissue, and attenuated neuronal apoptosis in the cortex at 24 h and 48 h after MCAO in rats. Western blotting analysis showed that MSCs-EVs significantly upregulated p-AMPK and downregulated p-JAK2, p-STAT3 and p-NF-κB. In addition, an AMPK pathway blocker reversed the effect of MSCs-EVs on brain damage.

Conclusion

These results indicate that MSCs-EVs protected MCAO-injured rats, possibly by regulating the AMPK and JAK2/STAT3/NF-κB signaling pathways. This study supports the use of MSCs-EVs as a potential treatment strategy for MCAO in the future.