ATF3-mediated transactivation of CXCL14 in HSCs during liver fibrosis.

BACKGROUND AND AIMS: Myofibroblasts, the primary producers of extracellular matrix, primarily originate from hepatic stellate cells (HSCs), and their activation plays a pivotal role in liver fibrosis. This study aimed to investigate the function of CXC motif ligand 14 (CXCL14) in the progression of liver fibrosis. APPROACH AND RESULTS: CXCL14 knockdown significantly reduced the extent of liver fibrosis. Using Ingenuity pathway analysis and qRT-PCR, activating transcription factor 3 (ATF3) was identified as a key upstream regulator of CXCL14 expression. Mechanistically, ATF3 was shown to bind to the CXCL14 promoter, promoting its transactivation by TGF-ß in HSCs. Notably, both global CXCL14 deletion (CXCL14-/-) and HSC/myofibroblast-specific CXCL14 knockdown significantly attenuated liver fibrosis in mice. RNA-seq comparisons between CXCL14-/- and WT mice highlighted Jak2 as the most significantly downregulated gene, implicating its role in the antifibrotic effects of CXCL14 suppression on HSC inactivation. Moreover, Jak2 overexpression reversed the inhibition of liver fibrosis caused by CXCL14 knockdown in vivo. CONCLUSIONS: These findings unveil a novel ATF3/CXCL14/Jak2 signalling axis in liver fibrosis, presenting potential therapeutic targets for the disease.

Effect of napabucasin and doxorubicin via the Jak2/Stat3 signaling pathway in suppressing the proliferation of neuroblastoma cells.

PURPOSE: Napabucasin (NP) is a natural compound that can suppress cancer cell proliferation and cell cycle by inhibition of the signal transducer and activator of transcription 3 (STAT3) gene. We examined the effects of NP on the proliferation and invasion of neuroblastoma cells (SH-SY5Y). METHODS: Human neuroblastoma SH-SY5Y cell line was used in this study. NP was administered to groups at the doses of 0.3-1 µM. Cell viability was analyzed by MTT assay. Real-time quantitative reverse transcription polymerase chain reaction and western blot analysis assessed the expressions of interleukin (IL)-6 dependent Jak2/Stat3 signaling pathway. The MTT cell viability method was applied to determine the antagonistic-synergistic effects and inhibitory concentration (IC50) doses of doxorubicin (DX) and NP. RESULTS: It was determined that 0.3-1 µM doses of NP killed the cells almost completely after 48 hours, and also that Jak2/Stat3 expressions decreased dose-dependently via IL-6. At the protein level, NP and DX were found to reduce Jak2 and Stat3 levels. CONCLUSIONS: NP showed that it suppresses the proliferation of neuroblastoma cells. Due to its inhibitory effect on Jak2 and Stat3, it can be used to prevent invasion of SH-SY5Y cells. NP, which can inactivate Jak2/Stat3, can be used as a treatment agent by combining with DX in proliferation pathway in neuroblastoma.

Effects of Ruxolitinib on Immune Checkpoint Molecule Expression in JAK2 V617F-Positive Cells.

BACKGROUND: This study aimed to explore the clinical significance of ruxolitinib and its effects on the proliferation and apoptosis of human erythroleukemia (HEL) cells and the expression of immune checkpoint molecules programmed death-1 (PD-1), programmed death-ligand 1 (PD-L1), and regulatory T cells (Tregs) in HEL cells and JAK2 V617F-positive patients with myeloproliferative neoplasms (MPNs). METHODS: JAK2 V617F-positive patients with MPNs admitted to the Baoding No. 1 Hospital from January 2016 to September 2023 were recruited, including 30 patients for the newly diagnosed group and 10 for the treatment group. Additionally, 15 healthy volunteers were selected as the control group. JAK2 V617F mutation was detected by using fluorescence quantitative PCR, and the expression levels of phosphorylated JAK2 (p-JAK2), PD-1, and PD-L1 in fresh bone marrow were examined by immunohistochemistry. HEL cells were treated with ruxolitinib at different concentrations (0, 50, 100, 250, 500, and 1,000 nmol/L). Cell viability was detected by CCK-8 assay. The mRNA expression levels of JAK2, PD-1, and PD-L1 were determined by using fluorescence quantitative PCR. The protein expression of p-JAK2 was detected by Western blot and those of PD-1 and PD-L1 were evaluated by flow cytometry. The expression of PD-1, PD-L1, and Tregs after the 48-hour co-culture of primary bone marrow cells and HEL cells were also analyzed by flow cytometry. RESULTS: In the newly diagnosed group, the bone marrow myeloid cells highly expressed p-JAK2, PD-1, and PD-L1. The Tregs expression in their peripheral blood increased and was significantly higher than those in the treatment and control groups (all p < 0.05). Ruxolitinib at different concentrations could inhibit the proliferation of HEL cells and was positively correlated with treatment time and dose. Additionally, ruxolitinib could reduce p-JAK2, PD-1, and PD-L1 expression in HEL cells and Tregs expression. CONCLUSIONS: Ruxolitinib reduces the expression of p-JAK2, PD-1, and PD-L1 in JAK2 V617F-positive cells by specifically inhibiting the JAK2 signaling pathway, thereby suppressing the progression of MPNs.

Design and synthesis of triazolopyridine derivatives as potent JAK/HDAC dual inhibitors with broad-spectrum antiproliferative activity.

A series of triazolopyridine-based dual JAK/HDAC inhibitors were rationally designed and synthesised by merging different pharmacophores into one molecule. All triazolopyridine derivatives exhibited potent inhibitory activities against both targets and the best compound 4-(((5-(benzo[d][1, 3]dioxol-5-yl)-[1, 2, 4]triazolo[1, 5-a]pyridin-2-yl)amino)methyl)-N-hydroxybenzamide (19) was dug out. 19 was proved to be a pan-HDAC and JAK1/2 dual inhibitor and displayed high cytotoxicity against two cancer cell lines MDA-MB-231 and RPMI-8226 with IC50 values in submicromolar range. Docking simulation revealed that 19 fitted well into the active sites of HDAC and JAK proteins. Moreover, 19 exhibited better metabolic stability in vitro than SAHA. Our study demonstrated that compound 19 was a promising candidate for further preclinical studies.

HPV16 E6-induced M2 macrophage polarization in the cervical microenvironment via exosomal miR-204-5p.

The persistent infection of high-risk human papillomavirus (HPV) and the progression of cervical cancer necessitate the involvement of microenvironmental immunity. As cervical lesions advance, there is an observed increase in the infiltration of type 2 (M2) macrophages. However, the precise mechanism driving this increased infiltration of M2 macrophages remains unclear. In this study, we investigated the role of exosomes in polarising M2 macrophages in cervical lesions associated with HPV E6. Through the analysis of bioinformatics data and clinical specimens, we discovered a positive correlation between HPV E6/E7 mRNA copy number and the level of M2 macrophage infiltration. Exosomes derived from HPV E6 overexpressed (HPV E6+) cervical squamous cell carcinoma (CESC) cells were found to induce the polarisation of macrophages towards M2 type. Specifically, miR-204-5p, enriched in HPV E6 + CESC exosomes, was transported into macrophages and triggered M2 macrophage polarisation by inhibiting JAK2. The clinical relevance of exosomal miR-204-5p in the progression of cervical lesions was validated through serum samples from 35 cases. Exosomal miR-204-5p emerges as a critical factor influencing M2 macrophage polarisation and is correlated with the severity of cervical lesions. Consequently, miR-204-5p could be used as a potential treatment and a candidate biomarker for cervical lesions.

LTF ameliorates cartilage endplate degeneration by suppressing calcification, senescence and matrix degradation through the JAK2/STAT3 pathway.

Intervertebral disc degeneration (IDD)-induced cervical and lumbar herniations are debilitating diseases. The function of intervertebral disc (IVD) mainly depends on the cartilage endplate (CEP), which provides support and waste removal. Therefore, IDD stems from the degeneration of CEP. Our study shows that the expression of lactotransferrin (LTF), an iron-binding protein, is significantly decreased in degenerated human and rat CEP tissues. In addition, we found that LTF knockdown promoted calcification, senescence, and extracellular matrix (ECM) degradation in human endplate chondrocytes. Furthermore, the in vivo experiment results confirmed that the JAK2/STAT3 pathway inhibitor AG490 significantly reversed these effects. In addition to investigating the role and mechanism of LTF in CEP degeneration, this study provides a theoretical basis and experimental evidence to improve IDD treatment.

Buzhong Yiqi decoction attenuates acquired myasthenia by regulating the JAK2/STAT3/AKT signaling pathway, inhibiting inflammation, and improving mitochondrial function.

Acquired myasthenia (AM), a debilitating autoimmune disease, is typically characterized by skeletal muscle fatigue and weakness. Despite advances in myasthenia gravis treatment, current approaches remain unsatisfactory and many result in unexpected side effects. Traditional Chinese medicine has shown great potential in the treatment of myasthenia gravis, including relieving myasthenic symptoms, improving patients' quality of life, and reducing Western medicine side effects. This study investigates the protective effects and mechanism of BZYQD in mice with acquired myasthenia. BZYQD alleviates the reduced grip strength and increased expression of MAFbx and MuRF-1 in mice with acquired myasthenia. It also reduces levels of pro-inflammatory factors IL-1ß, IL-6, and TNF-α in the mouse serum. In addition, BZYQD reduces ROS accumulation and the mitochondrial ROS production rate, while increasing ATP levels and mitochondrial membrane potential in mice with acquired myasthenia. Moreover, BZYQD decreases the expression of p-JAK2, p-STAT3, and p-AKT in the skeletal muscle of mice with acquired myasthenia. In summary, BZYQD reduces inflammation, enhances mitochondrial function, and regulates the JAK2/STAT3/AKT signaling pathway to treat acquired myasthenia.

Linoleyl acetate and mandenol alleviate HUA-induced ED via NLRP3 inflammasome and JAK2/STAT3 signalling conduction in rats.

Hyperuricemia (HUA) is characterized by elevated blood uric acid levels, which can increase the risk of erectile dysfunction (ED). Clinical studies have demonstrated satisfactory efficacy of a traditional Chinese medicine formula QYHT decoction in improving ED. Furthermore, the main monomeric components of this formula, linoleyl acetate and mandenol, demonstrate promise in the treatment of ED. This study established an ED rat model induced by HUA and the animals were administered with linoleyl acetate and mandenol. HE and TUNEL were performed to detect tissue changes, ELISA to measure the levels of serum testosterone (T), MDA, NO, CRP, and TNF-α and qPCR and WB to assess the expression levels of NLRP3, ASC, Caspase-1, JAK2, and STAT3 in whole blood. The findings showed that linoleyl acetate and mandenol improved kidney tissue morphology, reduced cell apoptosis in penile tissue, significantly increased T and NO levels, while substantially decreasing levels of MDA, CRP, and TNF-α. Meanwhile, the expression of NLRP3, ASC, and Caspase-1 mRNAs and proteins was markedly reduced, and the phosphorylation of JAK2 and STAT3 was inhibited. These findings were further validated through faecal microbiota transplantation results. Taken together, linoleyl acetate and mandenol could inhibit NLRP3 inflammasome activation, reduce inflammatory and oxidative stress responses, suppress the activity of JAK-STAT signalling pathway, ultimately providing a potential treatment for HUA-induced ED.

Role of the JAK2/STAT3 pathway on infection of Francisella novicida.

Francisella tularensis is a causative agent of the zoonotic disease tularemia, and is highly pathogenic to humans. The pathogenicity of this bacterium is largely attributed to intracellular growth in host cells. Although several bacterial factors important for the intracellular growth have been elucidated, including the type VI secretion system, the host factors involved in the intracellular growth of F. tularensis are largely unknown. To identify the host factors important for F. tularensis infection, 368 compounds were screened for the negative regulation of F. tularensis subsp. novicida (F. novicida) infection. Consequently, 56 inhibitors were isolated that decreased F. novicida infection. Among those inhibitors, we focused on cucurbitacin I, an inhibitor of the JAK2/ STAT3 pathway. Cucurbitacin I and another JAK2/STAT3 inhibitor, Stattic, decreased the intracellular bacterial number of F. novicida. However, these inhibitors failed to affect the cell attachment or the intrasaccular proliferation of F. novicida. In addition, treatment with these inhibitors destabilized actin filaments. These results suggest that the JAK2/STAT3 pathway plays an important role in internalization of F. novicida into host cells through mechanisms involving actin dynamics, such as phagocytosis.

Investigation of the mechanism of poly (ADP-ribose) polymerase (PARP) in elderly mouse myocardial ischemia-reperfusion injury.

This study investigated the role of Poly (ADP-ribose) Polymerase (PARP) in myocardial ischemia-reperfusion injury (MIRI) in elderly mice. It involves 30 elderly male KM mice divided into three groups: Sham, MIRI, and DPQ, where the MIRI and DPQ groups undergo myocardial ischemia-reperfusion with the DPQ group also receiving DPQ for PARP-1 inhibition. Over three weeks, assessments include histological analysis of myocardial lesions, left ventricular ejection fraction (LVEF) measurements, and evaluations of serum cardiac enzymes and inflammatory markers. This approach aims to understand the protective effects of DPQ in MIRI, focusing on its impact on cardiac health and inflammation via the JAK2/STAT3 pathway. The findings suggest that PARP activation exacerbates cardiac dysfunction and inflammation in MIRI by possibly modulating the JAK2/STAT3 signaling pathway. Inhibition of PARP-1 with DPQ mitigates these effects, as indicated by reduced myocardial lesions and inflammatory infiltration, improved LVEF, and altered levels of inflammatory markers and signaling molecules. However, the differences in STAT3 and p-STAT3 protein expression between the DPQ and MIRI groups were not statistically significant, suggesting that while PARP inhibition affects many aspects of MIRI pathology, its impact on the JAK2/STAT3 pathway may not fully explain the observed benefits. This study contributes to our understanding of the complex mechanisms underlying myocardial ischemia-reperfusion injury, particularly in the context of aging. It highlights the potential of PARP inhibition as a therapeutic strategy to attenuate cardiac dysfunction and inflammation in MIRI, though further research is necessary to fully elucidate the underlying molecular pathways and to explore the clinical relevance of these findings in humans.

Ruxolitinib-based senomorphic therapy mitigates cardiomyocyte senescence in septic cardiomyopathy by inhibiting the JAK2/STAT3 signaling pathway.

Background: Cellular senescence has emerged as a pivotal focus in cardiovascular research. This study investigates the previously unrecognized role of cellular senescence in septic cardiomyopathy (SCM) and evaluates senomorphic therapy using ruxolitinib (Rux) as a potential treatment option. Methods: We employed lipopolysaccharide (LPS)-induced neonatal rat cardiomyocytes (NRCMs) and two mouse models-LPS-induced and cecal ligation and puncture (CLP)-induced SCM models-to assess Rux's effects. RNA sequencing, western blotting (WB), quantitative polymerase chain reaction (qPCR), immunofluorescence, immunohistochemistry, senescence-associated ß-galactosidase (SA-ß-gal) assay, and other techniques were utilized to investigate underlying mechanisms. Results: Senescence-associated secretory phenotype (SASP) and cellular senescence markers were markedly elevated in LPS-induced NRCMs and SCM animal models, confirmed by the SA-ß-gal assay. Rux treatment attenuated SASP in vitro and in vivo, alongside downregulation of senescence markers. Moreover, Rux-based senomorphic therapy mitigated mitochondrial-mediated apoptosis, improved cardiac function in SCM mice, restored the balance of antioxidant system, and reduced reactive oxygen species (ROS) levels. Rux treatment restored mitochondrial membrane potential, mitigated mitochondrial morphological damage, and upregulated mitochondrial complex-related gene expression, thereby enhancing mitochondrial function. Additionally, Rux treatment ameliorated SCM-induced mitochondrial dynamic dysfunction and endoplasmic reticulum stress. Mechanistically, Rux inhibited JAK2-STAT3 signaling activation both in vitro and in vivo. Notably, low-dose Rux and ABT263 showed comparable efficacy in mitigating SCM. Conclusions: This study highlighted the potential significance of cellular senescence in SCM pathogenesis and suggested Rux-based senomorphic therapy as a promising therapeutic approach for SCM.

Lrig1 regulates cell fate specification of glutamatergic neurons via FGF-driven Jak2/Stat3 signaling in cortical progenitors.

The cell-intrinsic mechanisms underlying the decision of a stem/progenitor cell to either proliferate or differentiate remain incompletely understood. Here, we identify the transmembrane protein Lrig1 as a physiological homeostatic regulator of FGF2-driven proliferation and self-renewal of neural progenitors at early-to-mid embryonic stages of cortical development. We show that Lrig1 is expressed in cortical progenitors (CPs), and its ablation caused expansion and increased proliferation of radial/apical progenitors and of neurogenic transit-amplifying Tbr2+ intermediate progenitors. Notably, our findings identify a previously unreported EGF-independent mechanism through which Lrig1 negatively regulates neural progenitor proliferation by modulating the FGF2-induced IL6/Jak2/Stat3 pathway, a molecular cascade that plays a pivotal role in the generation and maintenance of CPs. Consistently, Lrig1 knockout mice showed a significant increase in the density of pyramidal glutamatergic neurons placed in superficial layers 2 and 3 of the postnatal neocortex. Together, these results support a model in which Lrig1 regulates cortical neurogenesis by influencing the cycling activity of a set of progenitors that are temporally specified to produce upper layer glutamatergic neurons.

Programmed death-ligand 1 expression in patients with primary or secondary myelofibrosis.

BACKGROUND: It has been described in mice models that myeloproliferative neoplasm (MPN) with JAK2-V617F mutation has an increased expression of programmed death-ligand 1 (PD-L1) in megakaryocytes leading to cancer immune evasion by inhibiting the T-lymphocytes. AIMS: To quantify and compare the PD-L1 expression on bone marrow (BM) of patients with MPN JAK2 positive, negative, and normal controls. METHODS: We collected BM of patients with MPN JAK2 positive, negative and normal controls from 1990 to 2019. We also created a scoring system to quantify PD-L1 expression in megakaryocytes. RESULTS: We obtained 14 BM with JAK2 positive PMF, 5 JAK2 negative PMF, and 10 patients with normal BM biopsies. PD-L1 expression was higher in the JAK2 positive group compared with the control group with a score of 212.6 versus 121.1 (t-value 2.05, p-value 0.025). In addition, the score was higher in the PMF group regardless of JAK2 mutational status when compared with the control group with score of 205.9 versus 121.1 (t-value 2.12, p-value 0.021). There was no difference in the PD-L1 score between the JAK2 negative versus the control group 187.2 versus 121.1 (t-value 1.02, p-value 0.162). CONCLUSION: These findings suggest that PMF patients with a JAK2 mutation have a higher PD-L1 expression in megakaryocytes compared with the control group. We postulate that the combination of checkpoint and JAK2 inhibitors may be an active treatment option in JAK2 mutated PMF given the higher PD-L1 expression.

Siweixizangmaoru Decoction Ameliorated Type II Collagen-Induced Arthritis in Rats via Regulating JAK2-STAT3 and NF-κB Signaling Pathway.

Siweixizangmaoru decoction (SXD) is widely used as an anti-rheumatoid arthritis (RA) in Tibet, however, the specific anti-inflammatory mechanism of SXD is still unclear. This research attempts to examine the efficacy and possible mechanisms of SXD in treating RA. The primary chemical components of SXD were identified using UHPLC-Q-Exactive Orbitrap MS. We established a lipopolysaccharide (LPS)-induced RAW264.7 macrophage inflammatory injury model to explore the anti-inflammatory mechanism of SXD and validated it through in vivo experiments. According to our research in vitro as well as in vivo, SXD exhibits anti-inflammatory qualities. SXD can suppress nitric oxide (NO) and pro-inflammatory factor production in RAW264.7 cells activated by LPS. The mechanism underlying this effect might be connected to the janus tyrosine kinase 2-signal transducer and activator of transcription 3 (JAK2/STAT3) and nuclear factor-κB (NF-κB) signaling pathways. In vivo, SXD alleviates joint swelling, decreases the generation of inflammatory factors in the serum, lowers oxidative stress, and improves joint damage. In short, SXD improves joint degeneration and lowers symptoms associated with RA by regulating inflammation via the suppression of NF-κB and JAK2/STAT3 signaling pathway activation.

[Therapeutic mechanism of Cynanchum wilfordii for ulcerative colitis: an analysis using UPLC-QE-MS, network pharmacology and metabolomics].

OBJECTIVE: To explore the targets and pathways of Cynanchum wilfordii for treatment of ulcerative colitis (UC). METHODS: UPLC-QE-MS was used to identify the components of Cynanchum wilfordii ethanol extract, and their targets were screened using public databases for construction of the core protein-protein interaction (PPI) network and GO and KEGG enrichment analyses. Forty male C57 mice were randomized into normal control group, model group, mesalazine group and Cynanchum wilfordii group (n=10), and in the latter 3 groups, mouse UC models were established by treatment with 2.5% DSS and the latter 2 groups drug interventions by gavage. The therapeutic effect was evaluated by recording body weight changes and DAI score. Pathological changes of the colon tissue were observed with HE and AB-PAS staining, and JAK2 and STAT3 protein expressions were detected with Western blotting. The metabolites and metabolic pathways were identified by metabonomics analysis. RESULTS: We identified 240 chemical components in Cynanchum wilfordii alcoholic extracts, including 19 steroids. A total of 177 Cynanchum wilfordii targets, 5406 UC genes, and 117 intersection genes were obtained. JAK2 and STAT3 were the core targets and significantly enriched in lipid and atherosclerosis pathways. Cynanchum wilfordii treatment significantly increased the body weight and decreased DAI score of UC mice (P < 0.05), alleviated intestinal pathologies, and decreased JAK2 and STAT3 protein expressions in the colon tissues. Most of the 83 intersecting differential metabolites between the control, model and Cynanchum wilfordii groups were identified as glycerophospholipids, arachidonic acid, and amino acids involving glycerophospholipid metabolism and other pathways. Correlation analysis suggested that the core targets of Cynanchum wilfordii for UC participated in regulation of the metabolites. CONCLUSION: Cynanchum wilfordii alleviates lipid and amino acid metabolism disorders to lessen UC in mice by regulating the core targets including JAK2 and STAT3 and the levels of endogenous metabolites.

The functional role of m6A demethylase ALKBH5 in cardiomyocyte hypertrophy.

Cardiomyocyte hypertrophy is a major outcome of pathological cardiac hypertrophy. The m6A demethylase ALKBH5 is reported to be associated with cardiovascular diseases, whereas the functional role of ALKBH5 in cardiomyocyte hypertrophy remains confused. We engineered Alkbh5 siRNA (siAlkbh5) and Alkbh5 overexpressing plasmid (Alkbh5 OE) to transfect cardiomyocytes. Subsequently, RNA immunoprecipitation (RIP)-qPCR, MeRIP-qPCR analysis and the dual-luciferase reporter assays were applied to elucidate the regulatory mechanism of ALKBH5 on cardiomyocyte hypertrophy. Our study identified ALKBH5 as a new contributor of cardiomyocyte hypertrophy. ALKBH5 showed upregulation in both phenylephrine (PE)-induced cardiomyocyte hypertrophic responses in vitro and transverse aortic constriction (TAC)/high fat diet (HFD)-induced pathological cardiac hypertrophy in vivo. Knockdown or overexpression of ALKBH5 regulated the occurrence of hypertrophic responses, including the increased cardiomyocyte surface areas and elevation of the hypertrophic marker levels, such as brain natriuretic peptide (BNP) and atrial natriuretic peptide (ANP). Mechanically, we indicated that ALKBH5 activated JAK2/STAT3 signaling pathway and mediated m6A demethylation on Stat3 mRNA, but not Jak2 mRNA, resulting in the phosphorylation and nuclear translocation of STAT3, which enhances the transcription of hypertrophic genes (e.g., Nppa) and ultimately leads to the emergence of cardiomyocytes hypertrophic growth. Our work highlights the functional role of ALKBH5 in regulating the onset of cardiomyocyte hypertrophy and provides a potential target for hypertrophic heart diseases prevention and treatment. ALKBH5 activated JAK2/STAT3 signaling pathway and mediated m6A demethylation on Stat3 mRNA, but not Jak2 mRNA, resulting in the phosphorylation and nuclear translocation of STAT3, which enhances the transcription of hypertrophic genes (e.g., Nppa) and ultimately leads to the emergence of cardiomyocytes hypertrophic growth.

Puerarin inhibits macrophage M1 polarization by combining STAT1 to reduce myocardial damage in EAM model mice.

Myocarditis is an inflammatory lesion of the myocardium that is caused by a variety of factors. At present, treatment of symptoms remains the main clinical intervention, but it cannot reduce the myocarditis damage caused by inflammation. M1 macrophages are thought to contribute significantly to the occurrence and development of inflammation by secreting a large number of proinflammatory factors. Puerarin is an isoflavone derivative isolated from pueraria that can be used as a dietary supplement and exerts wide range of anti-inflammatory and antioxidant effects. However, the mechanism underlying its anti-inflammatory effects needs to be further studied. The objective of this study was to investigate whether puerarin inhibited M1 polarization by affecting the JAK-STAT signaling pathway in a mouse model of autoimmune myocarditis, thus inhibiting the occurrence of inflammation in experimental autoimmune myocarditis (EAM) model mice. The results showed that EAM model mice treated with puerarin showed milder clinical symptoms and inflammatory infiltration than EAM model mice. Puerarin suppressed the in vivo and in vitro JAK1/2-STAT1 signal transduction in macrophages, thus inhibiting M1 polarization, reducing the secretion of proinflammatory factors, and ultimately decreasing IFN-γ and TNF-α levels in vivo, which led to myocardial apoptosis. Thus, puerarin could alleviate myocardial damage caused by inflammation. The conclusion of this study was that puerarin reduced myocardial damage in EAM model mice by regulating the polarization of macrophages toward M1, and this inhibitory effect may be achieved by inhibiting JAK1/2-STAT1 signaling.

Demethylzeylasteral ameliorates podocyte damage in murine lupus by inhibiting inflammation and enhancing autophagy.

BACKGROUND: Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with multiorgan and tissue involvement. Lupus nephritis (LN), an inflammatory condition of the kidneys associated with SLE, represents a significant cause of morbidity and mortality in SLE patients. Current immunosuppressive therapies for LN have limited efficacy and can lead to significant side effects. Demethylzeylasteral (DML) has shown promise in the treatment of LN, but its precise mechanism of action remains unclear. PURPOSE: To assess the therapeutic effects and potential molecular mechanisms of DML in LN METHODS: The study evaluated the renal protective effects of DML in MRL/lpr mice through assessments of immune complex levels, renal function, and pathological changes. Network pharmacology and transcriptomics approaches were used to elucidate the underlying mechanisms. Molecular docking, biacore assay, monoclonal antibody blocking experiments, and in vitro studies were conducted to verify the mechanisms of action. RESULTS: DML treatment reduced levels of anti-Sm and anti-dsDNA IgG antibodies, as well as serum creatinine and blood urea nitrogen levels. DML also mitigated glomerular damage and fibrosis. Mechanistically, DML alleviated podocyte damage by suppressing inflammation and enhancing autophagy through inhibition of the IL-17A/JAK2-STAT3 pathways. Additionally, DML exhibited high binding affinity with IL17A, JAK2, and STAT3. CONCLUSION: These findings provide strong evidence for the beneficial effects of DML in LN, suggesting its potential as a novel therapeutic strategy for improving renal function in autoimmune kidney diseases.

Myeloid-Specific JAK2 Contributes to Inflammation and Salt Sensitivity of Blood Pressure.

BACKGROUND: Salt sensitivity of blood pressure (SSBP), characterized by acute changes in blood pressure with changes in dietary sodium intake, is an independent risk factor for cardiovascular disease and mortality in people with and without hypertension. We previously found that elevated sodium concentration activates antigen-presenting cells (APCs), resulting in high blood pressure, but the mechanisms are unknown. Here, we hypothesized that APC-specific JAK2 (Janus kinase 2) through STAT3 (signal transducer and activator of transcription 3) and SMAD3 (small mothers against decapentaplegic homolog 3) contributes to SSBP. METHODS: We performed bulk or single-cell transcriptomic analyses following in vitro monocytes exposed to high salt and in vivo high sodium treatment in humans using a rigorous salt-loading/depletion protocol to phenotype SSBP. We also used a myeloid cell-specific CD11c+ JAK2 knockout mouse model and measured blood pressure with radiotelemetry after N-omega-nitro-L-arginine-methyl ester and a high salt diet treatment. We used flow cytometry for immunophenotyping and measuring cytokine levels. Fluorescence in situ hybridization and immunohistochemistry were performed to spatially visualize the kidney's immune cells and cytokine levels. Echocardiography was performed to assess cardiac function. RESULTS: We found that high salt treatment upregulates gene expression of the JAK/STAT/SMAD pathway while downregulating inhibitors of this pathway, such as suppression of cytokine signaling and cytokine-inducible SH2, in human monocytes. Expression of the JAK2 pathway genes mirrored changes in blood pressure after salt loading and depletion in salt-sensitive but not salt-resistant humans. Ablation of JAK2, specifically in CD11c+ APCs, attenuated salt-induced hypertension in mice with SSBP. Mechanistically, we found that SMAD3 acted downstream of JAK2 and STAT3, leading to increased production of highly reactive isolevuglandins and proinflammatory cytokine IL (interleukin)-6 in renal APCs, which activate T cells and increase production of IL-17A, IL-6, and TNF-α (tumor necrosis factor-alpha). CONCLUSIONS: Our findings reveal the APC JAK2 signaling pathway as a potential target for the diagnosis and treatment of SSBP in humans.