HOXB5 promotes the progression and metastasis of osteosarcoma cells by activating the JAK2/STAT3 signalling pathway

Objective

To investigate the involvement of the homeobox gene B5 (HOXB5) in the progression and metastasis of osteosarcoma.

Methods

The expression of HOXB5 in human osteosarcoma tissues and its correlation with clinical indicators were investigated using bioinformatics analysis and immunohistochemical labelling. Human osteosarcoma cells (HOS, MG63, U2OS, and Saos-2) and normal human osteoblasts (hFOB1.19) were cultivated. The expression of HOXB5 in these cells was detected using western blotting (WB) and RT‒PCR. Two cell lines exhibiting elevated HOXB5 expression were chosen and divided into three groups: the blank group (mock), control group (control) and transfection group (shHOXB5). The transfection group was infected with lentivirus expressing shRNAs targeting HOXB5. The transfection efficiency was detected by WB. Cell proliferation suppression was measured by CCK-8 and 5-ethynyl-2'-deoxyuridine (EdU) assays; the percentage of apoptotic cells was determined by flow cytometry; and cell migration and invasion were detected via the Transwell chamber test. WB was utilized to determine the protein expression of genes linked to metastasis (MMP2, MMP9), apoptosis (Bax, Bcl-2), and the JAK2/STAT3 pathway (JAK2, p-JAK2, STAT3, p-STAT3).

Results

In osteosarcoma tissues, HOXB5 expression was elevated and strongly correlated with distant metastasis. Silencing HOXB5 reduced the proliferation, migration and invasion of osteosarcoma cells; prevented the progression and metastasis of tumours in tumour-bearing nude mice; and reduced the activation of key proteins in the JAK2/STAT3 signalling pathway.

Conclusion

Through the JAK2/STAT3 signalling pathway, HOXB5 plays a crucial role in the malignant progression of osteosarcoma and is a promising target for osteosarcoma treatment.

Spexin ameliorated obesity-related metabolic disorders through promoting white adipose browning mediated by JAK2-STAT3 pathway

BACKGROUND

Spexin, a 14 amino acid peptide, has been reported to regulate obesity and its associated complications. However, little is known about the underlying molecular mechanism. Therefore, this study aimed to investigate the effects of spexin on obesity and explore the detailed molecular mechanisms in vivo and in vitro.

METHODS

Male C57BL/6J mice were fed a high-fat diet (HFD) for 12 weeks to induce obesity, and mice fed a standard fat diet were used as controls. Then, these mice were treated with SPX or Vehicle by intraperitoneal injection for an additional 12 weeks, respectively. The metabolic profile, fat-browning specific markers and mitochondrial contents were detected. In vitro, 3T3-L1 cells were used to investigate the molecular mechanisms.

RESULTS

After 12 weeks of treatment, SPX significantly decreased body weight, serum lipid levels, and improved insulin sensitivity in HFD-induced obese mice. Moreover, SPX was found to promote oxygen consumption in HFD mice, and it increased mitochondrial content as well as the expression of brown-specific markers in white adipose tissue (WAT) of HFD mice. These results were consistent with the increase in mitochondrial content and the expression of brown-specific markers in 3T3-L1 mature adipocytes. Of note, the spexin-mediated beneficial pro-browning actions were abolished by the JAK2/STAT3 pathway antagonists in mature 3T3-L1 cells.

CONCLUSIONS

These data indicate that spexin ameliorates obesity-induced metabolic disorders by improving WAT browning via activation of the JAK2/STAT3 signaling pathway. Therefore, SPX may serve as a new therapeutic candidate for treating obesity.

V-set and immunoglobulin domain containing 4 inhibits oxidative stress, mitochondrial dysfunction, and inflammation to attenuate Parkinson's disease progression by activating the JAK2/STAT3 pathway

OBJECTIVE

V-set and immunoglobulin domain containing 4 (VSIG4) inhibits neurological dysfunction, microglial M1 polarization, and inflammation to participate in the progression of neurological disorders, but evidence regarding Parkinson's disease (PD) is scarce. The present study intended to investigate the engagement of VSIG4 in PD progression, and the potential mechanism.

METHODS

BV-2 cells were treated with 1-Methyl-4-phenylpyridinium (MPP+) to establish PD model. MPP+ treated BV-2 cells were infected with VSIG4 overexpression adenovirus-associated virus (AAV) (oeVSIG4) and negative control AAV (oeNC), and AZD1480 (JAK2 inhibitor) was added to these cells.

RESULTS

MPP+ reduced VSIG4 mRNA (P < 0.05) and protein (P < 0.05) in BV-2 cells. Interestingly, VSIG4 reduced malondialdehyde (P < 0.01), reactive oxygen species (P < 0.01), NOD-like receptor family pyrin domain containing 3 (P < 0.05), cleaved-caspase1 (P < 0.05), tumor necrosis factor-α (P < 0.05), and interleukin-1β (P < 0.05), but increased glutathione (P < 0.05), mitochondrial membrane potential (P < 0.05), phosphorylation (p)-JAK2 (P < 0.05), and p-STAT3 (P < 0.01) in MPP+ treated BV-2 cells, which indicated that VSIG4 inhibited oxidative stress, mitochondrial dysfunction, and inflammation, as well as activated the JAK2/STAT3 pathway in PD model. Moreover, AZD1480 inhibited the JAK2/STAT3 pathway and aggravated oxidative stress, mitochondrial dysfunction, and inflammation in PD model (all P < 0.05). Importantly, AZD1480 attenuated the influence of VSIG4 on oxidative stress, mitochondrial dysfunction, inflammation, and the JAK2/STAT3 pathway in PD model (all P < 0.05).

CONCLUSION

VSIG4 suppresses oxidative stress, mitochondrial dysfunction, and inflammation by activating the JAK2/STAT3 pathway, which may be helpful in attenuating PD progression.

Targeting C21orf58 is a Novel Treatment Strategy of Hepatocellular Carcinoma by Disrupting the Formation of JAK2/C21orf58/STAT3 Complex

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide. Functionally uncharacterized genes are an attractive repository to explore candidate oncogenes. It is demonstrated that C21orf58 displays an oncogenic role in promoting cell growth, tumorigenesis and sorafenib resistance of HCC cells by abnormal activation of STAT3 signaling. Mechanistically, a novel manner to regulate STAT3 signaling that adaptor C21orf58 forms a ternary complex is reveal with N-terminal domain of STAT3 and SH2 domain of JAK2, by which C21orf58 overactivates wild-type STAT3 by facilitating its phosphorylation mediated by JAK2, and hyper-activates of constitutively mutated STAT3 due to preferred binding with C21orf58 and JAK2. Moreover, it is validated that inhibition of C21orf58 with drug alminoprofen, selected by virtual screening, could effectively repress the viability and tumorigenesis of HCC cells. Therefore, it is identified that C21orf58 functions as an oncogenic adaptor, reveal a novel regulatory mechanism of JAK2/STAT3 signaling, explain the cause of abnormal activity of activated mutants of STAT3, and explore the attractive therapeutic potential by targeting C21orf58 in HCC.

TRIM29 modulates proteins involved in PTEN/AKT/mTOR and JAK2/STAT3 signaling pathway and suppresses the progression of hepatocellular carcinoma

Tripartite motif-containing 29 (TRIM29), also known as the ataxia telangiectasia group D-complementing (ATDC) gene, has been reported to play an oncogenic or tumor suppressive role in developing different tumors. So far, its expression and biological functions in hepatocellular carcinoma (HCC) remain unclear. We investigated TRIM29 expression pattern in human HCC samples using quantitative RT-PCR and immunohistochemistry. Relationships between TRIM29 expression level, clinical prognostic indicators, overall survival (OS), and disease-free survival (DFS) were evaluated by Kaplan-Meier analysis and Cox proportional hazards model. A series of in vitro experiments and a xenograft tumor model were conducted to detect the functions of TRIM29 in HCC cells. RNA sequencing, western blotting, and immunochemical staining were performed to assess the molecular regulation of TRIM29 in HCC. We found that the mRNA and protein levels of TRIM29 were significantly reduced in HCC samples, compared with adjacent noncancerous tissues, and were negatively correlated with poor differentiation of HCC tissues. Survival analysis confirmed that lower TRIM29 expression significantly correlated with shorter OS and DFS of HCC patients. TRIM29 overexpression remarkably inhibited cell proliferation, migration, and EMT in HCC cells, whereas knockdown of TRIM29 reversed these effects. Moreover, deactivation of the PTEN/AKT/mTOR and JAK2/STAT3 pathways might be involved in the tumor suppressive role of TRIM29 in HCC. Our findings indicate that TRIM29 in HCC exerts its tumor suppressive effects through inhibition of the PTEN/AKT/mTOR and JAK2/STAT3 signaling pathways and may be used as a potential biomarker for survival in patients with HCC.

E2F5 Targeted by Let-7d-5p Facilitates Cell Proliferation, Metastasis and Immune Escape in Gallbladder Cancer

BACKGROUND

Gallbladder cancer (GBC) remains a serious cause of cancer-related mortality across the globe. E2F5 has been identified to as a known oncogene in various cancers. However, the special functions of E2F5 have not been investigated in GBC.

AIMS

To explore the regulatory functions of E2F5 and its related molecular regulatory mechanism in GBC progression.

METHODS

The expression of genes were examined through qRT-PCR, western blot and IHC assay. The cell proliferation was assessed through CCK-8 and EDU assays. The cytotoxicity was tested through LDH assay. The percentage of CD8+ T cells and cell apoptosis were evaluated through flow cytometry. The binding ability was detected through luciferase reporter assay. The tumor growth was assessed through in vivo assays.

RESULTS

In this study, it was demonstrated that E2F5 expression was evaluated in GBC, and resulted into poor prognosis. Bioinformatics analysis revealed E2F5 as a target for let-7d-5p, which when overexpressed, suppressed the metastasis and proliferation of GBC through the downregulation of E2F5. It was discovered that E2F5 activates JAK2/STAT3 signaling which is suppressed by let-7d-5p, implicating this pathway as one of the effectors of the oncogenic effects of ESF5 in GBC. E2F5 had been confirmed to aggravate tumor growth in vivo.

CONCLUSION

E2F5 targeted by let-7d-5p facilitated cell proliferation, metastasis and immune escape in GBC through the JAK2/STAT3 pathway.

ANGPTL4 accelerates ovarian serous cystadenocarcinoma carcinogenesis and angiogenesis in the tumor microenvironment by activating the JAK2/STAT3 pathway and interacting with ESM1

BACKGROUND

Ovarian cancer (OC) is a malignant neoplasm that displays increased vascularization. Angiopoietin-like 4 (ANGPTL4) is a secreted glycoprotein that functions as a regulator of cell metabolism and angiogenesis and plays a critical role in tumorigenesis. However, the precise role of ANGPTL4 in the OC microenvironment, particularly its involvement in angiogenesis, has not been fully elucidated.

METHODS

The expression of ANGPTL4 was confirmed by bioinformatics and IHC in OC. The potential molecular mechanism of ANGPTL4 was measured by RNA-sequence. We used a series of molecular biological experiments to measure the ANGPTL4-JAK2-STAT3 and ANGPTL4-ESM1 axis in OC progression, including MTT, EdU, wound healing, transwell, xenograft model, oil red O staining, chick chorioallantoic membrane assay and zebrafish model. Moreover, the molecular mechanisms were confirmed by Western blot, Co-IP and molecular docking.

RESULTS

Our study demonstrates a significant upregulation of ANGPTL4 in OC specimens and its strong association with unfavorable prognosis. RNA-seq analysis affirms that ANGPTL4 facilitates OC development by driving JAK2-STAT3 signaling pathway activation. The interaction between ANGPTL4 and ESM1 promotes ANGPTL4 binding to lipoprotein lipase (LPL), thereby resulting in reprogrammed lipid metabolism and the promotion of OC cell proliferation, migration, and invasion. In the OC microenvironment, ESM1 may interfere with the binding of ANGPTL4 to integrin and vascular-endothelial cadherin (VE-Cad), which leads to stabilization of vascular integrity and ultimately promotes angiogenesis.

CONCLUSION

Our findings underscore that ANGPTL4 promotes OC development via JAK signaling and induces angiogenesis in the tumor microenvironment through its interaction with ESM1.

Amentoflavone Mitigates Cyclophosphamide-Induced Pulmonary Toxicity: Involvement of -SIRT-1/Nrf2/Keap1 Axis, JAK-2/STAT-3 Signaling, and Apoptosis

Background and objectives: Cyclophosphamide (CPA) is an alkylating agent that is used for the management of various types of malignancies and as an immunosuppressive agent for the treatment of immunological disorders. However, its use is limited by its potential to cause a wide range of pulmonary toxicities. Amentoflavone (AMV) is a flavonoid that had proven efficacy in the treatment of disease states in which oxidative stress, inflammation, and apoptosis may play a pathophysiologic role. This study investigated the potential ameliorative effects of the different doses of AMV on CPA-induced pulmonary toxicity, with special emphasis on its antioxidant, anti-inflammatory, and apoptosis-modulating effects. Materials and methods: In a rat model of CPA-induced pulmonary toxicity, the effect of AMV at two dose levels (50 mg/kg/day and 100 mg/kg/day) was investigated. The total and differential leucocytic counts, lactate dehydrogenase activity, and levels of pro-inflammatory cytokines in the bronchoalveolar lavage fluid were estimated. Also, the levels of oxidative stress parameters, sirtuin-1, Keap1, Nrf2, JAK2, STAT3, hydroxyproline, matrix metalloproteinases 3 and 9, autophagy markers, and the cleaved caspase 3 were assessed in the pulmonary tissues. In addition, the histopathological and electron microscopic changes in the pulmonary tissues were evaluated. Results: AMV dose-dependently ameliorated the pulmonary toxicities induced by CPA via modulation of the SIRT-1/Nrf2/Keap1 axis, mitigation of the inflammatory and fibrotic events, impaction of JAK-2/STAT-3 axis, and modulation of the autophagic and apoptotic signals. Conclusions: AMV may open new horizons towards the mitigation of the pulmonary toxicities induced by CPA.

IL-6/JAK2/STAT3 axis mediates neuropathic pain by regulating astrocyte and microglia activation after spinal cord injury

After spinal cord injury (SCI), the control of activated glial cells such as microglia and astrocytes has emerged as a promising strategy for neuropathic pain management. However, signaling mechanism involved in glial activation in the process of neuropathic pain development and maintenance after SCI is not well elucidated. In this study, we investigated the potential role and mechanism of the JAK2/STAT3 pathway associated with glial cell activation in chronic neuropathic pain development and maintenance after SCI. One month after contusive SCI, the activation of JAK2/STAT3 pathway was markedly upregulated in both microglia and astrocyte in nociceptive processing regions of the lumbar spinal cord. In addition, both mechanical allodynia and thermal hyperalgesia was significantly inhibited by a JAK2 inhibitor, AG490. In particular, AG490 treatment inhibited both microglial and astrocyte activation in the lumbar (L) 4-5 dorsal horn and significantly decreased levels of p-p38MAPK, p-ERK and p-JNK, which are known to be activated in microglia (p-p38MAPK and p-ERK) and astrocyte (p-JNK). Experiments using primary cell cultures also revealed that the JAK2/STAT3 pathway promoted microglia and astrocyte activation after lipopolysaccharide stimulation. Furthermore, JAK2/STAT3 signaling and pain behaviors were significantly attenuated when the rats were treated with anti-IL-6 antibody. Finally, minocycline, a tetracycline antibiotic, inhibited IL-6/JAK2/STAT3 signaling pathway in activated glial cells and restored nociceptive thresholds and the hyperresponsiveness of dorsal neurons. These results suggest an important role of the IL-6/JAK2/STAT3 pathway in the activation of microglia and astrocytes and in the maintenance of chronic below-level pain after SCI.

Levistilide A ameliorates neuroinflammation via inhibiting JAK2/STAT3 signaling for neuroprotection and cognitive improvement in scopolamine-induced Alzheimer's disease mouse model

Alzheimer's disease (AD) is a progressive neurodegenerative disease associated with cognitive impairment and dementia, which has become a major public health problem. There are no effective therapeutic agents used to treat AD in clinic for the extremely complex pathogenesis. Here we identify Levistilide A (LA), one of the major active natural terpene lactone constituents from Chinese herbal medicine Angelicae sinensis and Chuanxiong Rhizoma, as a potent neuroinflammation inhibitor for neuroprotection and cognitive improvement of AD. We show that LA suppresses neuronal apoptosis, restores cholinergic system function, and lowers neuroinflammation in vivo to improve scopolamine (SCOP)-induced learning and memory deficits. In addition, LA inhibits the release of IL-1β, IL-6 and TNF-α, while increasing the production of IL-4 and IL-10 for anti-inflammatory effects in LPS or Aβ-induced BV2 and HMC3 cells. Furthermore, the conditioned medium (CM) from LA-treated BV2 or HMC3 cells enhances the viability of SH-SY5Y and HT-22 cells, and LA reverses M1 to M2 phenotype transformation of BV2 and HMC3 cells accompanied by the inhibited Iba-1 expression and mRNA level of IL-1β, IL-6, TNF-α and NOS2, and the increased expression of ARG1, CD206 and CD163. Mechanistically, we analyze JAK2/STAT3 signaling as possible targets of LA using network pharmacology approaches, and further experimentally validate that LA inhibits the phosphorylation of JAK2 and STAT3, and STAT3 expression within nucleus both in vitro and in vivo. Collectively, we identify LA as a potential neuroinflammation inhibitor for neuroprotection and cognitive improvement, which is expected to be a candidate for AD therapy.

The mechanism of LZ-8-mediated immune response in the mouse model of Parkinson's disease

Parkinson's disease (PD) is associated with microscopic changes in the brain, particularly substantia nigra (SN). Ganoderma lucidum immunoregulatory protein (rLZ-8) is might confer protective effects against PD. We developed a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced murine model of PD and determined the effects of rLZ-8 on molecular and cellular components of SN and whole brain tissue. The levels of SOD, GSH-Px, p-JAK2 and p-STAT3 in the brain tissue and SN were downregulated, while IL-6, IL-1β, and TNF-α and MDA were upregulated. These effects were significantly reversed upon treatment rLZ-8. In summary, oxidative stress and inflammatory response in PD can be alleviated using rLZ-8.

Leptin Promotes the Proliferation and Neuronal Differentiation of Neural Stem Cells through the Cooperative Action of MAPK/ERK1/2, JAK2/STAT3 and PI3K/AKT Signaling Pathways

The potential of neural stem cells (NSCs) for neurological disorders the treatment has relied in large part upon identifying the NSCs fate decision. The hormone leptin has been reported to be a crucial regulator of brain development, able to influence the glial and neural development, yet, the underlying mechanism of leptin acting on NSCs' biological characteristics is still poorly understood. This study aims to investigate the role of leptin in the biological properties of NSCs. In this study, we investigate the possibility that leptin may regulate the NSCs' fate decision, which may promote the proliferation and neuronal differentiation of NSCs and thus act positively in neurological disorders. NSCs from the embryonic cerebral cortex were used in this study. We used CCK-8 assay, ki67 immunostaining, and FACS analysis to confirm that 25-100 ng/mL leptin promotes the proliferation of NSCs in a concentration-dependent pattern. This change was accompanied by the upregulation of p-AKT and p-ERK1/2, which are the classical downstream signaling pathways of leptin receptors b (LepRb). Inhibition of PI3K/AKT or MAPK/ERK signaling pathways both abolished the effect of leptin-induced proliferation. Moreover, leptin also enhanced the directed neuronal differentiation of NSCs. A blockade of the PI3K/AKT pathway reversed leptin-stimulated neurogenesis, while a blockade of JAK2/STAT3 had no effect on it. Taken together, our results support a role for leptin in regulating the fate of NSCs differentiation and promoting NSCs proliferation, which could be a promising approach for brain repair via regulating the biological characteristics of NSCs.

Arylsulfatase D is a prognostic biomarker that promotes glioma cells progression through JAK2/STAT3 pathway and M2 macrophage infiltration

Background

Arylsulfatase D (ARSD) belongs to the sulfatase family and plays a crucial role in maintaining the proper structure of bone and cartilage matrix. Although several researches have revealed the functions of ARSD in tumor progression, the prognostic value of ARSD in glioma and the related mechanisms have not been fully investigated.

Methods

We performed a pan-cancer analysis of ARSD, and investigated the relationship between expression of ARSD and overall survival (OS) in multiple glioma datasets. ROC curves and nomograms were created to investigate the predictive capacity of ARSD. Immune and analysis were conducted to investigate the mechanisms underlying the roles of ARSD in glioma. Glioma tissue samples were collected to verify the expression of ARSD in glioma, while the functions of ARSD were explored using cell experiment. M2 macrophage infiltration assay was used to determine the relation between ARSD and tumor immune microenvironment.

Results

Survival analysis indicated that individuals with high ARSD expression in glioma had a shorter survival time. Cox analysis showed that ARSD had a good ability for predicting prognosis in glioma. Immune analysis suggested that ARSD could regulate immune cell infiltration and affect the Cancer-Immunity Cycle to create an immunosuppressive environment. Combined with cell experiment and bioinformatic analysis, we found that ARSD can promote glioma progression through regulation of JAK2/STAT3 pathway and M2 macrophage infiltration.

Conclusion

Our study found that ARSD can promote glioma development by regulating immune microenvironment and JAK2/STAT3 signaling pathway, which provided a potential therapy target for glioma treatment.

Molecular characterization and function of JAK/STAT pathway in IPEC-J2 cells during Clostridium perfringens beta2 toxin stimulation

Intestinal infection with C. perfringens is responsible for outbreaks of diarrhea in piglets. Janus kinase / signal transducer and activator of transcription (JAK/STAT) is a vital signaling pathway that regulates cellular activity and inflammatory response, closely correlated with multiple diseases development and advances. Currently, the potential effect of JAK/STAT on C. perfringens beta2 (CPB2) treatment on porcine intestinal epithelial (IPEC-J2) cells has not been explored. The expression of JAK/STAT genes or proteins in IPEC-J2 cells induced by CPB2 were observed by qRT-PCR and Western blot, and further used WP1066 to explore the effect of JAK2/STAT3 on mechanism employed by CPB2 on apoptosis, cytotoxicity, oxidative stress and inflammatory cytokines of IPEC-J2 cells. JAK2, JAK3, STAT1, STAT3, STAT5A and STAT6 were highly expressed in CPB2-induced IPEC-J2 cells, among which STAT3 had the highest expression. Moreover, apoptosis, cytotoxicity and oxidative stress were attenuated via blocking the activation of JAK2/STAT3 by using WP1066 in CPB2-treated IPEC-J2 cells. Furthermore, WP1066 significantly suppressed the secretion of interleukin (IL)-6, IL-1β and TNF-α induced by CPB2 in IPEC-J2 cells.Our findings provide some insights into the functional roles of JAK2/STAT3 in piglets against to C. perfringens infection.

Osteoclast-Derived Exosomal miR-5134-5p Interferes with Alveolar Bone Homeostasis by Targeting the JAK2/STAT3 Axis

Background

In chronic periodontitis, exosomes transport various informative substances between osteoclasts and osteoblasts in alveolar bone. Herein, we aimed to investigate the effect of exosomal micro-ribonucleic acid (miRNA/miR)-5134-5p derived from osteoclasts on osteoblastic proliferation and differentiation and the development of periodontitis in vivo and in vitro.

Methods

The effects of OC-Exos on the proliferation and differentiation of osteoblasts were identified by Real-time quantitative reverse polymerase chain reaction (qRT-PCR), Western blot(WB), alkaline phosphatase(ALP) staining, etc. Exosomal miRNA expression was analyzed by sequencing. The sites of miRNA action were predicted through TargetScan and tested by double luciferase assay. After transfecting miR-5134-5p mimic/inhibitor into osteoblasts, we measured the proliferation and differentiation of osteoblasts by ALP staining and WB, etc. Furthermore, OC-Exos were injected into the gingival sulcus at the ligation site. Inflammation was observed by Hematoxylin-eosin (H&E) staining, the expression of inflammatory factors were detected by qRT-PCR, the resorption of alveolar bone was observed by Micro CT.

Results

Osteoblastic proliferation and differentiation were negatively regulated by OC-Exos in vitro. miRNA sequencing analysis revealed that miR-5134-5p expression was significantly elevated in OC-Exos, which also increased in osteoblasts following OC-Exo intervention. The dual-luciferase assay revealed that miR-5134-5p and Janus kinase 2 (JAK2) had binding sites. miR-5134-5p-mimics could upregulate miR-5134-5p expression in osteoblasts while downregulating Runt-related transcription factor 2(Runx2), phosphorylated-JAK2 (p-JAK2), and phosphorylated-signal transducer and activator of transcription 3 (p-STAT3) expression and inhibited osteogenic differentiation. However, miR-5134-5p-inhibitor had the opposite effect. In vivo, the OC-Exo group demonstrated morphological disruption of periodontal tissue, massive inflammatory cell infiltration, upregulation of inflammatory factors mRNA expression, a significant decrease in BV/TV, and an increase in the cementoenamel junction and alveolar bone crest distance.

Conclusion

Osteoclast-derived exosomal miR-5134-5p inhibits osteoblastic proliferation and differentiation via the JAK2/STAT3 pathway. OC-Exos exacerbate periodontal tissue inflammation and accelerate alveolar bone resorption in mice with experimental periodontitis.

Guizhi Fuling capsule relieves memory deficits by inhibition of microglial neuroinflammation through blocking JAK2/STAT3 pathway in presenilin1/2 conditional double knockout mice

Chronic neuroinflammation has been regarded as an important part of the pathological initiation of Alzheimer's disease (AD), which is associated with the regulation of microglial activation. Preventing microglial activation to inhibit neuroinflammation may become a potential target for the treatment of neurodegenerative diseases. Guizhi Fuling capsule (GZFL) has a strong repression on inflammatory responses. Here, the presenilin1/2 conditional double knockout (PS cDKO) mice, a well-established mouse model of AD, were divided into: WT mice (WT), WT mice+GZFL (WT+GZFL), PS cDKO mice (cDKO), and PS cDKO mice+GZFL (cDKO+GZFL). Mice in the WT+GZFL and cDKO+GZFL group were fed standard chow containing 2000 ppm GZFL for 90 days. After 60 days of GZFL treatment, mice were given to behavioral tests for 30 days in order to explore the effects of GZFL on cognitive and motor function. Then, mice were sacrificed for examining the effects of GZFL on inflammation. Furthermore, primary microglia were obtained from neonatal Sprague-Dawley rats and pretreated with or without GZFL (50 μg/ml) for 1 h in the absence or presence of lipopolysaccharide (LPS) (100 ng/ml) stimulation to speculate whether the underlying mechanism of GZFL's anti-inflammatory potential was closely associated with Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway. Our findings indicated that GZFL has the ability to alleviate memory deficits in PS cDKO mice, which attributes to the improvement of neuroinflammation by inhibiting microglial activation and the levels of pro-inflammatory mediators. In addition, GZFL could inverse the tau hyperphosphorylation and the lessened expression of synaptic proteins in hippocampus of PS cDKO mice. Furthermore, GZFL prevented LPS-induced neuroinflammatory responses in primary microglia by decreasing the levels of pro-inflammatory mediators. It is noteworthy that therapeutic effects of GZFL on memory impairment are depended on the inhibition of neuroinflammatory responses by the blockage of JAK2/STAT3 signaling pathway. Taken together, GZFL may be an effective compound Chinese medicine for the improvement and postponement of neurodegenerative progression in AD.

Lp-PLA2 silencing ameliorates inflammation and autophagy in nonalcoholic steatohepatitis through inhibiting the JAK2/STAT3 pathway

Background

Nonalcoholic steatohepatitis (NASH), a common cause of liver-related morbidity and mortality worldwide, is characterized by inflammation and hepatocellular injury. Our research focuses on lipoprotein-associated phospholipase A2 (Lp-PLA2), an inflammation-related biomarker that has recently garnered interest in the context of NASH due to its potential roles in disease pathogenesis and progression.

Methods

We established a NASH mouse model using a high-fat diet (HFD) and treated it with sh-Lp-PLA2 and/or rapamycin (an mTOR inhibitor). Lp-PLA2 expression in NASH mice was detected by qRT-PCR. Serum levels of liver function parameters and inflammatory cytokines were detected using corresponding assay kits. We examined pathological changes in liver using hematoxylin-eosin, oil red O, and Masson staining, and observed autophagy through transmission electron microscopy. The protein levels of Lp-PLA2, mTOR, light chain 3 (LC3) II/I, phosphorylated Janus kinase 2 (p-JAK2)/JAK2, and phosphorylated signal transducer and activator of transcription 3 (p-STAT3)/STAT3 were determined by western blotting. Kupffer cells extracted from C57BL/6J mice were treated to replicate NASH conditions and treated with sh-Lp-PLA2, rapamycin, and/or a JAK2-inhibitor to further verify the roles and mechanisms of Lp-PLA2 in NASH.

Results

Our data indicate an upregulation of Lp-PLA2 expression in HFD-induced NASH mice. Silencing Lp-PLA2 in NASH mice reduced liver damage and inflammation markers (aspartate aminotransferase (AST), alanine aminotransferase (ALT), total cholesterol (TC), triglycerides (TG), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6)), while increasing IL-10 levels, an anti-inflammatory cytokine. Additionally, Lp-PLA2 silencing decreased lipid and collagen accumulation and promoted autophagy. The beneficial effects of sh-Lp-PLA2 on NASH were enhanced by rapamycin. Furthermore, Lp-PLA2 silencing resulted in the downregulation of the expression of p-JAK2/JAK2 and p-STAT3/STAT3 in NASH mice. Similar results were observed in Kupffer cells treated under NASH conditions; Lp-PLA2 silencing promoted autophagy and repressed inflammation, effects which were potentiated by the addition of rapamycin or a JAK2-inhibitor.

Conclusion

Our findings suggest that silencing Lp-PLA2 promotes autophagy via deactivating the JAK2/STAT3 signaling pathway, thereby restraining NASH progression. This highlights the potential therapeutic value of targeting Lp-PLA2, adding a new dimension to our understanding of NASH pathogenesis and treatment strategies.

Liuwei Anxiao San protects gastric mucosa from gastric ulcer in rats by regulating the JAK2/STAT3 pathway

Mongolian medicine prescriptions are recognized as promising gastroprotective agents. This study is to explore the effects and mechanisms of Liuwei Anxiao San (LAS) in gastric ulcer (GU). GU rat models were established using acetic acid, followed by treatment with LAS at different doses and/or the JAK2 agonist Coumermycin A1 (CA1). The ulcerous area and inhibition rates were calculated. The mucosal damage and cell apoptosis in gastric tissues were assessed by H&E and TUNEL staining. The activities of SOD, GSH-Px, and CAT, and MDA levels were measured. The levels of pro-inflammatory and anti-inflammatory factors were determined by ELISA. The activation of the JAK2/STAT3 pathway was determined by Western blot. As the results suggested, LAS dose-dependently ameliorated gastric mucosal damage and inhibited oxidative stress and inflammatory response, evidenced by increased activities of SOD, GSH-Px, and CAT, decreased MDA level, increment of anti-inflammatory factors and decrement of pro-inflammatory factors, and inhibited the activation of the JAK2/STAT3 pathway in GU rats. CA1 partly abolished the function of LAS on gastric mucosal injury, oxidative stress, and inflammation in GU rats. In conclusion, LAS protects against gastric mucosal injury in GU rats through inhibition of oxidative stress and inflammation by suppressing the JAK2/STAT3 pathway.

Protective Effect of Unfractionated Heparin on Lipopolysaccharide-Induced Acute Respiratory Distress Syndrome in Neonatal Mice via the JAK2/STAT3 Signaling Pathway

BACKGROUND

Neonatal acute respiratory distress syndrome (ARDS) is a clinical disorder characterized by excessive acute inflammatory response in lung parenchyma and has high morbidity and mortality. However, the therapeutic treatments are still lacking. The aim of this study is to evaluate the role of unfractionated heparin in neonatal ARDS and explore the underlying mechanism of its effects.

METHODS

To conduct the ARDS model, the mouse pups were treated by intraperitoneal injection of lipopolysaccharide (LPS) (10 mg/kg). For unfractionated heparin intervention group, C57BL/6 mouse pups received a single subcutaneous injection of unfractionated heparin (400 IU/kg) 30 minutes prior to LPS. The survival rate was recorded for each group. Histological analysis was used to evaluate lung injury. MPO (myeloperoxidase) concentration level in lung tissues and extracellular histones in serum were detected by enzyme linked immunosorbent assay (ELISA). A commercially available kit was used to detect inflammatory cytokine levels in serum. Real time quantitative polymerase chain reaction (qPCR) and western blot were used to detect the mRNA and protein in the JAK2/STAT3 signaling pathway, respectively.

RESULTS

Intervention of unfractionated heparin significantly increased the survival rate of mouse pups with ARDS, restored lung architecture, inhibited neutrophil infiltration as evidenced by reduced MPO concentration, and attenuated the LPS-induced inflammatory responses, characterized by the down-regulation of proinflammatoy factors and up-regulation of anti-inflammatory factor when compared with the ARDS group. In addition, the concentration of extracellular histones, which have been proven to be mediated in the pathogenesis of ARDS, was diminished by unfractionated heparin. Moreover, the protein expressions of p-JAK2 (Y1007/1008) and p-STAT3 (Y705) in the ARDS group were remarkably up-regulated, which were reversed by unfractionated heparin.

CONCLUSIONS

Unfractionated heparin protects LPS-induced ARDS via inhibiting JAK2/STAT3 pathway in neonatal mice, which might present a novel therapeutic target for ARDS of neonates.

VSIG4 Silencing Inhibits Glioblastoma Growth by Regulating the JAK2/STAT3 Pathway

Background

Glioblastoma (GBM) is the most common malignant primary brain tumour in adults. VSIG4 has been identified to be associated with GBM. We aimed to determine the downstream regulatory mechanisms of VSIG4 in GBM.

Methods

Differential expression of VSIG4 was analysed using GEPIA. The expression of VSIG4 was assessed by RT-qPCR and its downstream genes were screened by transcriptome sequencing. The expression of pyroptosis-related proteins and the JAK2/STAT3 pathway was measured by Western blotting. GBM cell viability, migration, and invasion were detected using CCK-8, scratch, and Transwell assays. The levels of pyroptosis-related factors were measured using ELISA. The effect of VSIG4 on GBM tumour growth in vivo was explored by constructing a xenograft tumour model.

Results

VSIG4 expression was upregulated in GBM. Functionally, silencing of VSIG4 inhibited proliferation, invasion, and migration of U251 and LN229 cells, and promoted pyroptosis. Mechanically, transcriptome sequencing revealed that the JAK2/STAT3 pathway might be a downstream regulator of VSIG4. Further studies proved that silencing of VSIG4 enhanced the expression of p-JAK2 and p-STAT3, and the JAK2/STAT3 pathway inhibitor relieved the suppression of VSIG4 silencing on GBM cell viability, invasion, and migration. Furthermore, in vivo experiments further validated that knockdown of VSIG4 inhibited the growth of GBM tumors.

Conclusion

In GBM, silencing VSIG4 promoted pyroptosis and inhibited tumor progression by regulating the JAK2/STAT3 signaling pathway.

Modified Erchen decoction ameliorates cognitive dysfunction in vascular dementia rats via inhibiting JAK2/STAT3 and JNK/BAX signaling pathways

BACKGROUND

Vascular dementia (VaD) is one of the most common clinical syndromes of progressive neurocognitive dysfunction with uncertain mechanisms. Modified Erchen decoction (MECD), developed from "Erchen decoction (ECD)" recorded in "Taiping Huimin Heji Jufang", showed a good effect in the treatment of VaD. However, its therapeutic mechanism is still unclear.

PURPOSE

This study aimed to elucidate the multi-target mechanisms of MECD against VaD in vivo and in vitro.

METHODS

VaD model was established by two-vessel obstruction (2-VO) in Sprague-Dawley rats. Six groups, including the control, 2-VO operation, MECD treatment (2.5, 5.0 and 10.0 g kg^-1 d^-1), donepezil hydrochloride (positive control, 0.45 g kg^-1 d^-1) were designed in the whole experiment. After oral administration for 4 weeks, the effects of MECD were verified by behavioral experiments, histological observation, and biochemical index analysis. The chemical profiling of MECD was performed by UHPLC-Orbitrap Fusion-HRMS, and a "compound-target-pathway" multivariate network was constructed to validate and elucidate its pharmacological mechanisms.

RESULTS

Compared with 2-VO group, MECD treatment significantly alleviated anxiety and improved spatial memory in VaD rats according to the open field test (OFT) and Y-maze test. A significant increase in neuron number was observed from hematoxylin and eosin (H&E) stained images in cornu ammonis 1 (CA1) of the hippocampal region after MECD treatment. On the one hand, MECD reduced the plasma levels of triglyceride (TG), low-density lipoprotein (LDL), malondialdehyde (MDA), and amyloid-beta 42 (Aβ42), and inhibited mRNA expression of interleukin-1 beta (Il-1β) and Il-6 in the hippocampus. On the other hand, superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) were significantly increased after treatment with MECD. Moreover, MECD reduced the mRNA expression and protein expression of janus kinase 2 (JAK2), signal transducer and activator of transcription 3 (STAT3), c-Jun N-terminal kinase (JNK), and BCL2-associated X (BAX) in the brain of 2-VO rats. Furthermore, 71 compounds were identified from the extract of MECD. Among them, liquiritin and isochlorogenic acid C gave inhibiting effects on the mRNA expression of Jnk. In addition, liquiritin and hesperetin were conformed with the inhibition of Jak2 transcription level in vitro experiments.

CONCLUSION

MECD has demonstrated a significant amelioration effect on cognitive dysfunction in VaD rats via JAK2/STAT3 and JNK/BAX signaling pathways, which represents an innovative insight into the "activate blood and eliminate phlegm" theory.

Exercise preconditioning attenuates cerebral ischemia-induced neuronal apoptosis, Th17/Treg imbalance, and inflammation in rats by inhibiting the JAK2/STAT3 pathway

BACKGROUND

Exercise preconditioning (EP) is essential for preventing ischemic stroke. Recent studies have shown that EP exerts neuroprotective effects in the cerebral ischemia-reperfusion injury model. Nonetheless, there have been few reports on the relationship between EP and the Th17/Treg balance. Moreover, it is unclear whether the JAK2/STAT3 pathway is responsible for the neuroprotective effect of EP. Therefore, we aimed to explore the impact of EP, other than the anti-inflammatory and antiapoptotic functions, on the Th17/Treg balance via the JAK2/STAT3 pathway in a middle cerebral artery occlusion (MCAO)-induced model.

RESULTS

Fifty rats were randomly allocated into five groups, including the sham group (n = 10), EP+sham group (n = 10), MCAO group (n = 10), EP+MCAO group (n = 10), and EP+MCAO+JAK2/STAT3 pathway agonist (coumermycin A1, CA1) group (n = 10). The results indicated that EP alleviated neurological deficits, reduced infarct volume, and ameliorated neuronal apoptosis induced by MCAO. Additionally, the MCAO-induced Th17/Treg imbalance could be rectified by EP. The decreased levels of IL-10 and Foxp3 and increased IL-17 and RORα in the MCAO group were reversed by EP treatment. Regarding inflammation, EP reduced the concentrations of IL-6 and IL-17 and elevated those of IL-10 and TGF-β. The neuroprotective effects of EP were accompanied by decreased phosphorylation of JAK2 and STAT3. Furthermore, CA1 pretreatment diminished all the beneficial effects of EP partially.

CONCLUSION

Our findings suggest that EP contributes to attenuating neuronal apoptosis, Th17/Treg imbalance, and inflammation induced by MCAO via inhibiting the JAK2/STAT3 pathway, indicating its therapeutic potential in ischemic stroke.

Muscle-derived stem cell exosomes with overexpressed miR-214 promote the regeneration and repair of rat sciatic nerve after crush injury to activate the JAK2/STAT3 pathway by targeting PTEN

Introduction

This study aimed to investigate the effect of muscle-derived stem cell (MDSC) exosomes with overexpressed miR-214 on the regeneration and repair of rat sciatic nerve after crush injury and its molecular mechanism.

Methods

First, primary MDSCs, Schwann cells (SCs) and dorsal root ganglion (DRG) neurons were isolated and cultured, and the characteristics of MDSCs-derived exosomes were identified by molecular biology and immunohistochemistry. NC mimics and miR-214 mimics were transfected to obtain exo-NC and exo-miR-214. An in vitro co-culture system was established to determine the effect of exo-miR-214 on nerve regeneration. The restoration of sciatic nerve function of rats by exo-miR-214 was evaluated by walking track analysis. Immunofluorescence for NF and S100 was used to detect the regeneration of axon and myelin sheath in injured nerve. The Starbase database was used to analyze the downstream target genes of miR-214. QRT-PCR and dual luciferase reporter assays were used to validate the miR-214 and PTEN interaction relationship. And the expression of the JAK2/STAT3 pathway-related proteins in sciatic nerve tissues were detected by western blot.

Results

The above experiments showed that MDSCs-derived exosomes with overexpressed miR-214 was found to promote the proliferation and migration of SCs, increase the expression of neurotrophic factors, promote axon extension of DRG neurons and positively affect the recovery of nerve structure and function. In addition, PTEN was a target gene of miR-214. Exo-miR-214 can significantly inhibit the expression level of PTEN, increase the protein expression levels of p-JAK2 and p-STAT3 and the ratio of p-JAK2/JAK2 and p-STAT3/STAT3, also MDSCs-derived exosomes with overexpressed miR-214 can reduce the occurrence of denervated muscle atrophy.

Conclusion

In summary, the MDSCs-derived exosomes with overexpressed miR-214 is involved in peripheral nerve regeneration and repair in rats after sciatic nerve crush injury to activate the JAK2/ STAT3 pathway by targeting PTEN.

Resveratrol Loaded by Folate-Modified Liposomes Inhibits Osteosarcoma Growth and Lung Metastasis via Regulating JAK2/STAT3 Pathway

Background

Osteosarcoma is a malignant bone tumor with a high rate of lung metastasis and mortality. It has been demonstrated that resveratrol can inhibit tumor proliferation and metastasis, but its application is limited due to poor water solubility and low bioavailability. In this study, we proposed to prepare folate-modified liposomes loaded with resveratrol to investigate its anti-osteosarcoma effect in vitro and in vivo.

Methods

We prepared and characterized resveratrol liposomes modified with folate (denoted as, FA-Res/Lps). The effects of FA-Res/Lps on human osteosarcoma cell 143B proliferation, apoptosis, and migration were investigated by MTT, cell cloning, wound-healing assay, transwell, and flow cytometry. A xenograft tumor and lung metastasis model of osteosarcoma was constructed to study the therapeutic effects of FA-Res/Lps on the growth and metastasis of osteosarcoma in vivo.

Results

The FA-Res/Lps were prepared with a particle size of 118.5 ± 0.71 and a small dispersion coefficient of 0.154 ± 0.005. We found that FA-modified liposomes significantly increased resveratrol uptake by osteosarcoma cells 143B in flow cytometric assay, resulting in FA-Res/Lps, which inhibit tumor proliferation, migration and induce apoptosis more effectively than free Res and Res/Lps. The mechanism of action may be associated with the inhibition of JAK2/STAT3 signaling. In vivo imaging demonstrated that FA-modified DiR-modified liposomes significantly increased the distribution of drugs at the tumor site, leading to significant inhibition of osteosarcoma growth and metastasis by FA-Res/Lps. Furthermore, we found that FA-Res/Lps did not cause any adverse effects on mice body weight, liver, or kidney tissues.

Conclusion

Taken together, the anti-osteosarcoma effect of resveratrol is significantly enhanced when it is loaded into FA-modified liposomes. FA-Res/Lps is a promising strategy for the treatment of osteosarcoma.

Huangkui capsule alleviates doxorubicin-induced proteinuria via protecting against podocyte damage and inhibiting JAK/STAT signaling

ETHNOPHARMACOLOGICAL RELEVANCE

Huangkui capsule (HKC), a Chinese patent medicine, has been widely used in China as adjuvant therapy for chronic kidney disease (CKD). It displays superior anti-proteinuria efficacy than losartan in patients with CKD at stages 1-2, however, the mechanism of HKC alleviating proteinuria has not been well elucidated.

AIM OF THE STUDY

This study aims to confirm the therapeutic effect and investigate associated underlying mechanism of HKC against proteinuria by in vivo and in vitro experiments.

MATERIALS AND METHODS

We established a doxorubicin (DOX) induced proteinuria mouse model to evaluate kidney function by biochemical markers measurement and to observe histopathological alterations by hematoxylin and eosin (H&E), Masson's trichrome and Periodic Acid-Schiff (PAS)-stained sections of renal, respectively. Moreover, the expressions of Nephrin and Podocin were measured by immunohistochemistry (IHC) and western blotting analysis to investigate podocyte damage. Furthermore, we established Mouse Podocyte Clone-5 (MPC-5) injury model to identify the active components of HKC against podocyte damage by detecting the expressions of Nephrin, Podocin, and ZO-1 proteins. At last, the key protein levels of Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway were assessed by western blotting analysis to explore the underlying mechanism of HKC against proteinuria.

RESULTS

Our results showed that HKC administration for three consecutive weeks dose-dependently ameliorated both renal function and histopathological damages, elevated the expressions of Nephrin and Podocin, the pivotal molecules maintaining filtration function of the podocyte, indicating the promising protective effect against podocyte injury under DOX exposure. Consistently, in vitro experiments showed HKC administration effectively reversed the abnormal expressions of Nephrin and Podocin in MPC-5 cells treated with DOX, suggesting its protective effect against podocyte injury to maintain filtration barrier integrity. In addition, Hibifolin was identified as the most active ingredients in HKC, which suppressed upstream JAK2/STAT3 and PI3K/Akt pathway phosphorylation to maintain the structural and functional integrity of podocyte filtration barrier. Of note, AG490, a selective JAK2 inhibitor, was used to further affirm the role of Hibifolin involving in regulation JAK2/STAT3.

CONCLUSIONS

Our study suggested that HKC may protect podocytes via JAK2/STAT3 and PI3K/Akt pathway to display its effects of ameliorating proteinuria.

Alpinetin inhibits neuroinflammation and neuronal apoptosis via targeting the JAK2/STAT3 signaling pathway in spinal cord injury

BACKGROUND

A growing body of research shows that drug monomers from traditional Chinese herbal medicines have antineuroinflammatory and neuroprotective effects that can significantly improve the recovery of motor function after spinal cord injury (SCI). Here, we explore the role and molecular mechanisms of Alpinetin on activating microglia-mediated neuroinflammation and neuronal apoptosis after SCI.

METHODS

Stimulation of microglia with lipopolysaccharide (LPS) to simulate neuroinflammation models in vitro, the effect of Alpinetin on the release of pro-inflammatory mediators in LPS-induced microglia and its mechanism were detected. In addition, a co-culture system of microglia and neuronal cells was constructed to assess the effect of Alpinetin on activating microglia-mediated neuronal apoptosis. Finally, rat spinal cord injury models were used to study the effects on inflammation, neuronal apoptosis, axonal regeneration, and motor function recovery in Alpinetin.

RESULTS

Alpinetin inhibits microglia-mediated neuroinflammation and activity of the JAK2/STAT3 pathway. Alpinetin can also reverse activated microglia-mediated reactive oxygen species (ROS) production and decrease of mitochondrial membrane potential (MMP) in PC12 neuronal cells. In addition, in vivo Alpinetin significantly inhibits the inflammatory response and neuronal apoptosis, improves axonal regeneration, and recovery of motor function.

CONCLUSION

Alpinetin can be used to treat neurodegenerative diseases and is a novel drug candidate for the treatment of microglia-mediated neuroinflammation.

A novel alkaloid compound, DCZ0358, exerts significant antitumor activity in bortezomib-resistant multiple myeloma cells through inhibition of JAK2/STAT3 pathway

Multiple myeloma (MM), the second most common haematological malignancy, is currently incurable because patients often develop multiple drug resistance and experience subsequent relapse of the disease. This study aims to identify a potential therapeutic agent that can counter bortezomib (BTZ) resistance in MM. DCZ0358, a novel alkaloid compound, is found to exert potent cytotoxic effects against BTZ-resistant MM cells in vivo and in vitro. The anti-myeloma activity of DCZ0358 is associated with inhibition of cell proliferation, promotion of cell apoptosis via caspase-mediated apoptotic pathways, and induction of G0/G1 phase arrest via downregulation of cyclin D1, CDK4, and CDK6. Further investigation of the molecular mechanism shows that DCZ0358 suppresses the JAK2/STAT3 signaling pathway. In conclusion, DCZ0358 can successfully counter BTZ resistance in MM cells. This study provides evidence that warrants future preclinical assessments of DCZ0358 as a therapeutic agent against BTZ resistance in MM.

FANCD2 inhibits ferroptosis by regulating the JAK2/STAT3 pathway in osteosarcoma

BACKGROUND

This research aimed to investigate the roles of fanconi anemia complementation group D2 (FANCD2) on the regulation of ferroptosis in osteosarcoma progression.

METHODS

The function of FANCD2 on cell viability, invasion, migration, and tumor growth were explored. FANCD2 and pathway-related genes were determined by western blot. Ferroptosis-associated markers were determined, including lipid peroxidation, labile iron pool (LIP), ferrous iron (Fe²⁺), and ferroptosis-related genes.

RESULTS

FANCD2 expression was increased in osteosarcoma cells. FANCD2 knockdown reduced cell viability, invasion, and migration of osteosarcoma cells. FANCD2 knockdown regulated ferroptosis-related gene expression, and distinctly increased the levels of LIP, Fe²⁺, and lipid peroxidation, and these effects were reversed by a ferroptosis inhibitor Fer-1. In addition, JAK2 and STAT3 expression were reduced by silencing of FANCD2, and STAT3 activator (colivelin) distinctly reversed tumor suppressor effects of FANCD2 silencing on osteosarcoma development.

CONCLUSION

These findings suggested that FANCD2 silencing could suppress osteosarcoma cell viability, migration, invasion, and tumor growth, and induced ferroptosis by regulating the JAK2/STAT3 axis. These findings may provide novel therapeutic ideas for clinical treatment of osteosarcoma.

Exosomal RBP4 potentiated hepatic lipid accumulation and inflammation in high-fat-diet-fed mice by promoting M1 polarization of Kupffer cells

Exosomes containing various biological cargoes have potential to be novel diagnostic biomarkers for metabolic diseases. In this study, retinol-binding protein 4 (RBP4) was found to be enriched in serum exosomes, and its increased levels could be considered as an independent risk factor for the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Exosomal RBP4 (exo-RBP4), primarily derived from hepatocytes, significantly enhanced the M1-like polarization of Kupffer cells (KCs) via promoting the activation of NOX2 and NF-κB and reactive oxygen species (ROS) accumulation, resulting in the over-production of inflammatory cytokines including TNF-α. Subsequently, those excess cytokines remarkably increased the levels of intracellular free fatty acid uptake and lipogenesis-related genes (FAS and SREBP-1c) but decreased fatty acid degradation-related genes (CPT-1 and PPARα) in palmitic acid-treated LO2 cells. More notably, TNF-α significantly elevated RBP4 transcription by activating STAT3 in hepatocytes, playing a positive role in NAFLD development. Intravenous injection with RBP4 (50 μg/kg) potentiated hepatic lipid accumulation, M1-type KC proportion, and serum pro-inflammatory cytokine levels in the hepatic tissues of high-fat-diet-fed mice. Collectively, these data indicated that exo-RBP4 converted KCs to M1 subtype by mediating the NOX2/ROS/NF-κB pathway, subsequently promoting de novo lipogenesis in hepatocytes by TNF-α secretion to activate the JAK2/STAT3 signaling pathway. Therefore, this study uncovered a novel intercellular communication between the inflammatory microenvironment and lipid metabolism for fostering NAFLD progression and found the potential of exo-RBP4 as a novel diagnostic biomarker and therapeutic target for NAFLD.

Ulinastatin affects focal cerebral ischemia-reperfusion injury via SOCS1-mediated JAK2/STAT3 signalling pathway

Cerebral ischemia results in loss of cerebral blood flow, which contributes to neuronal damage, neurocognitive impairment, as well as learning and memory difficulties. Although reperfusion is necessary to restore the blood supply to the brain, it also leads to several detrimental effects on the brain. The purpose of this study was to assess the effects of ulinastatin (UTI) on preventing focal cerebral ischemia/reperfusion-induced injury (FCIRI). First, a rat model of FCIRI was established and treated with UTI. The effects of UTI on FCIRI in rats were evaluated using Morris water maze assay, triphenyl tetrazolium chloride staining, TUNEL, western blot assay, and enzyme-linked immunosorbent assay analysis. UTI was found to improve the learning memory ability, reduce infarction area, inhibit apoptosis and decrease inflammation in FCIRI rats. Messenger RNA microarray analysis of hippocampal tissues revealed that suppressor of cytokine signalling-1 (SOCS1) was the downstream target of UTI in FCIRI. SOCS1 depletion impaired the protective effect of UTI on FCIRI in rats. SOCS1 blocked the activation of the JAK2/STAT3 pathway. JAK2 inhibitor caused the JAK2/STAT3 pathway deficit, hence reversing the effect of sh-SOCS1 on FCIRI in rats. Taken together, our results demonstrate that UTI alleviated FCIRI in rats, which was, to some extent, related to SOCS1-mediated JAK2/STAT3 pathway.

Angelica sinensis Polysaccharide and Astragalus membranaceus Polysaccharide Accelerate Liver Regeneration by Enhanced Glycolysis via Activation of JAK2/STAT3/HK2 Pathway

The promotion of liver regeneration is crucial to avoid liver failure after hepatectomy. Angelica sinensis polysaccharide (ASP) and Astragalus membranaceus polysaccharide (AMP) have been identified as being associated with hepatoprotective effects. However, their roles and specific mechanisms in liver regeneration remain to be elucidated. In the present study, it suggested that the respective use of ASP or AMP strikingly promoted hepatocyte proliferation in vitro with a wide range of concentrations (from 12.5 μg/mL to 3200 μg/mL), and a stronger promoting effect was observed in combined interventions. A significantly enhanced liver/body weight ratio (4.20%) on day 7 and reduced serum transaminase (ALT 243.53 IU/L and AST 423.74 IU/L) and total bilirubin (52.61 IU/L) levels on day 3 were achieved by means of ASP-AMP administration after partial hepatectomy in mice. Metabonomics showed that differential metabolites were enriched in glycolysis with high expression of beta-d-fructose 6-phosphate and lactate, followed by significantly strengthened lactate secretion in the supernatant (0.54) and serum (0.43) normalized to control. Upon ASP-AMP treatment, the knockdown of hexokinase 2 (HK2) or inhibited glycolysis caused by 2-deoxy-d-glucose decreased hepatocyte proliferation in vitro and in vivo. Furthermore, pathway analysis predicted the role of JAK2/STAT3 pathway in ASP-AMP-regulated liver regeneration, and phosphorylation of JAK2 and STAT3 was proven to be elevated in this promoting process. Finally, downregulated expression of HK2, an attenuated level of lactate secretion, and reduced hepatocyte proliferation were displayed when STAT3 was knocked out in vitro. Therefore, it can be concluded that ASP-AMP accelerated liver regeneration and exerted a hepatoprotective effect after hepatectomy, in which the JAK2/STAT3/HK2 pathway was actively involved in activating glycolysis.

Interleukin-22 exacerbates angiotensin II-induced hypertensive renal injury

Hypertensive renal injury (HRI) is a main cause of end-stage renal diseases, and CD4+ T cells and the secreted inflammatory cytokines contribute to the progress of HRI. However, the exact mechanisms remain unidentified in HRI, and there is still a shortage of effective treatments. Here, we aim to explore the role of interleukin-22 (IL-22) and its underlying mechanism in HRI. Serum IL-22 level and peripheral Th22 cells frequency in patients with HRI were detected by ELISA and flow cytometry respectively. Angiotension II (Ang II) was infused subcutaneously to C57BL/6 mice for 28 days. Hypertensive mice were treated with recombinant IL-22 (rIL-22), anti-IL-22 antibody, or JAK2/STAT3 pathway blocker AG-490 respectively. Blood pressure (BP), urinary albumin/creatinine ratio (UACR), serum creatinine (Scr) and renal histopathology were measured; renal Th22 cells proportion were evaluated; inflammatory factors were evaluated by ELISA; JAK2/STAT3 pathway and fibrosis related factors expression in kidney were detected by Western blot. Serum IL-22 and Th22 cells proportion in kidney of mice were elevated after Ang II infusion. Compared to Ang II-infused mice, treatment with rIL-22 resulted in further increased UACR, Scr, renal pathological damage, inflammation and renal fibrosis, accompanied by elevated BP and JAK2/STAT3 pathway activation. Conversely, anti-IL-22 antibody reduced inflammation, renal fibrosis and BP in Ang II treated mice. AG490 could compromised the above effects of rIL-22. Taken together, recombinant IL-22 may aggravate hypertensive renal damage mediated by Ang II in mice, which may be through promoting JAK2/STAT3 pathway activation. Anti-IL-22 antibody exerts the opposite effects. These data suggest the IL-22 signaling maybe a novel therapeutic target for the treatment of hypertensive renal injury.

Protective mechanisms of 10-gingerol against myocardial ischemia may involve activation of JAK2/STAT3 pathway and regulation of Ca2+ homeostasis

10-Gingerol (10-Gin), an active ingredient extracted from ginger, has been reported to have beneficial effects on the cardiovascular system. However, its protective effects on myocardial ischemia (MI) and the underlying cellular mechanisms are still unclear. To investigate the protection conferred by 10-Gin against MI injury and its potential mechanisms in cardiomyocytes via patch-clamp and molecular biology techniques. A rat MI model was established using the subcutaneous injection of isoproterenol (85 mg/kg) administered on two consecutive days. 10-Gin was pre-administered to rats for seven days to assess its cardio-protection. The patch-clamp and IonOptix Myocam detection techniques were used to investigated 10-Gin's effects on L-type Ca²⁺ channels (LTCCs), Ca²⁺ transients and cell contractility in isolated rat cardiomyocytes. 10-Gin administration alleviated MI injury, improved cardiac function and myocardial histopathology, reduced myocardial infarct area, downregulated oxidative stress and Ca²⁺ levels, and decreased the expression of apoptotic factors. Importantly, 10-Gin led to an increase in phosphorylated Janus kinase 2 and signal transducer and activator of transcription 3 (JAK2 and STAT3, respectively) expressions. Furthermore, 10-Gin inhibited LTCCs in a concentration-dependent manner with a half-maximal inhibitory concentration of 75.96 μM. Moreover, 10-Gin administration inhibited Ca²⁺ transients and cell contractility. Our results suggest that 10-Gin exerts cardioprotective effects on MI in vivo and in vitro in connection with the inhibition of oxidative stress and apoptosis via activation of the JAK2/STAT3 signalling pathway, and regulation of Ca²⁺ homeostasis by LTCCs.

Arginine regulates inflammation response-induced by Fowl Adenovirus serotype 4 via JAK2/STAT3 pathway

Background

Fowl Adenovirus serotype 4 (FAdV-4) infection causes severe inflammatory response leading to hepatitis-hydropericardium syndrome (HHS) in poultry. As an essential functional amino acid of poultry, arginine plays a critical role in anti-inflammatory and anti-oxidative stress.

Results

In this study, the differential expression genes (DEGs) were screened by transcriptomic techniques, and the DEGs in gene networks of inflammatory response-induced by FAdV-4 in broiler’s liver were analyzed by Kyoto encyclopedia of genes and genomes (KEGG) enrichment. The results showed that the cytokines pathway and JAK/STAT pathway were significantly enriched, in which the DEGs levels of IL-6, IL-1β, IFN-α, JAK and STAT were significantly up-regulated after FAdV-4 infection. It was further verified with real-time fluorescence quantitative polymerase chain reaction (Real-time qPCR) and Western blotting (WB) in vitro and in vivo. The findings demonstrated that FAdV-4 induced inflammatory response and activated JAK2/STAT3 pathway. Furthermore, we investigated whether arginine could alleviate the liver inflammation induced by FAdV-4. After treatment with 1.92% arginine level diet to broilers or 300 μg/mL arginine culture medium to LMH cell line with FAdV-4 infection at the same time, we found that the mRNA levels of IL-6, IL-1β, IFN-α and the protein levels of p-JAK2, p-STAT3 were down-regulated, compared with FAdV-4 infection group. Furthermore, we confirmed that the inflammation induced by FAdV-4 was ameliorated by pre-treatment with JAK inhibitor AG490 in LMH cells, and it was further alleviated in LMH cells treatment with AG490 and ARG.

Conclusions

These above results provide new insight that arginine protects hepatocytes against inflammation induced by FAdV-4 through JAK2/STAT3 signaling pathway.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-022-03282-9.

The mechanism of low-dose radiation-induced upregulation of immune checkpoint molecule expression in lung cancer cells

INTRODUCTION

This study explored the effect of low-dose radiation on the expression of immune checkpoint molecules in lung cancer cells and its mechanism, as well as the antitumour effect of combined low-dose radiation and immune checkpoint inhibitors.

METHODS

Western blot analysis was used to assess the expression of the immune checkpoint molecules CD47, PD-L1, FGL-1 and CD155 in lung cancer cells after radiation. Western blotting was also used to explore changes in the JAK2/STAT3 pathway. CD8⁺ T lymphocyte infiltration in tumour tissues were assessed by immunohistochemistry in a mouse model. The inhibitory effect of low-dose radiation combined with PD-L1 or CD47 inhibitors on tumor growth was evaluated by measuring tumor volume.

RESULTS

In response to low-dose irradiation, the expression of CD47 and PD-L1 in A549 and LLC cells was increased, the expression of p-JAK2 and p-STAT3 was also increased. AG490-mediated inhibition of the JAK2/STAT3 pathway before irradiation significantly reduced the expression of p-JAK2 and p-STAT3 in lung cancer cells, in the meantime, expression of CD47 and PD-L1 was also reduced. Conventional dose exposure exhibited the same trend. PD-L1 and CD47 protein levels increased after low-dose irradiation in an LLC tumour-bearing mouse model. Low-dose irradiation combined with PD-L1 or CD47 inhibitor treatment reduced levels of PD-L1 or CD47 in tumour tissues, increased the proportion of CD8⁺ T lymphocytes, and significantly inhibited tumour growth.

CONCLUSIONS

Both low-dose and regular-dose irradiation upregulate expression of the immune checkpoint molecules CD47 and PD-L1 in lung cancer cells, and the mechanism may be related to the JAK2/STAT3 pathway. Furthermore, low-dose irradiation combined with PD-L1 or CD47 inhibitors significantly inhibits tumour growth.

Osteoinductive activity of bisdemethoxycurcumin and its synergistic protective effect with human amniotic mesenchymal stem cells against ovariectomy-induced osteoporosis mouse model

Osteoporosis is a common disease characterized by skeletal fragility and microarchitectural deterioration. However, existing conventional drugs exhibit limited efficacy and can elicit severe adverse effects; moreover, and novel stem cell-based therapies have not exhibited sufficient therapeutic efficacy. Our hypothesis is that an appropriate osteogenic inducer may improve their therapeutic efficacy. In this study, we found that bisdemethoxycurcumin (BDMC) stimulates the differentiation of human amniotic mesenchymal stem cells (hAMSCs) into osteoblasts without inducing cytotoxicity. Here BDMC enhances calcium deposition in hAMSCs, while promoting the expression of early and late markers of osteoblast differentiation, including ALP, runt-related transcription factor 2, osterix, COL1-α1, osteocalcin, and osteopontin at the transcriptional and translational levels. Mechanistically, BDMC was found to activate the JAK2/STAT3 pathway; whereas AG490 (JAK2/STAT3 pathway inhibitor) inhibited BDMC functioning. Subsequently, we found that the combinatorial therapy of BDMC and hAMSC had a positive synergistic effect on osteoporotic mouse model induced by bilateral ovariectomy, including inhibiting bone loss and bone resorption and improving bone micro-architecture. Moreover, BDMC inhibited production of the bone resorption markers C-terminal telopeptide of type I collagen, and tartrate resistant acid phosphatase, while promoting serum levels of bone formation markers OCN, and procollagen I N-terminal propeptide. BDMC also improved liver and kidney function in osteoporotic mouse model. Collectively, BDMC improved osteoporosis by enhancing hAMSC osteogenesis and exhibited a protective effect on liver and kidney function in an osteoporotic mouse model. Hence, BDMC may serve as an effective adjuvant, and combined therapy with hAMSCs is a promising new approach toward osteoporosis treatment.

Homeodomain-containing gene 10 contributed to breast cancer malignant behaviors by activating Interleukin-6/Janus kinase 2/Signal transducer and activator of transcription 3 pathway

Homeodomain‑containing gene 10 (HOXC10) has been identified as an oncogene in various malignancies. Nevertheless, the role and function of HOXC10 in breast cancer (BC) remain unclear. RT-qPCR and Western blot were used to detect the mRNA and protein levels of genes, respectively. CCK-8, transwell, and TUNEL assays were performed to evaluate cell viability, invasion, migration, and apoptosis of BC cells in vitro. The xenograft model was established to examine the effect of HOXC10 on tumor growth in vivo. Our results indicated that HOXC10 expression was increased in BC and correlated with an unsatisfactory prognosis. Functional assays indicated that HOXC10 overexpression promoted cell proliferation and metastasis, and suppressed cell apoptosis of BC, while HOXC10 knockdown showed opposite trends. Furthermore, in vitro and in vivo assays uncovered that HOXC10 promoted the tumorigenesis of BC via the activation of IL-6/JAK2/STAT3 signaling. Overall, our study revealed that HOXC10 could function as a tumor promotor in BC by upregulating IL-6 levels to activate the JAK2/STAT3 signaling pathway.

Hypoxia inducible factor-3α promotes osteosarcoma progression by activating KDM3A-mediated demethylation of SOX9

Hypoxia/oxygen-sensing signally is closely associated with many tumor progressions, including osteosarcoma (OS). Previous research principally focused on the function of hypoxia-inducible factor (HIF)-1α and HIF-2α as the major hypoxia-associated transcription factors in OS, however, the role of HIF-3α has not been investigated. Our study found that HIF-3α was upregulated in OS tissues and cell lines. HIF-3α overexpression facilitated cell proliferation and invasion, and inhibited apoptosis, whereas HIF-3α knockdown showed the opposite results. Chromatin immunoprecipitation analysis revealed that lysine demethylase 3A (KDM3A) expression was transcriptionally activated by HIF-3α under hypoxia, and KDM3A occupied the SRY-box transcription factor 9 (SOX9) gene promoter region through H3 lysine 9 dimethylation (H3K9me2). Additionally, rescue results revealed that KDM3A or SOX9 overexpression reversed the effects of HIF-3α silence on cell functions. The Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway inhibitor cucurbitacin I suppressed the promotive effects of HIF-3α overexpression on cell proliferation, invasion and TAK2/STAT3 pathway. Finally, OS cell line MG-63 transfected with HIF-3α short hairpin RNA (HIF-3α shRNA) were subcutaneously injected into nude mice, and the results found that HIF-3α knockdown significantly inhibited the xenograft tumor growth of OS in vivo. In conclusion, this study reveals that HIF-3α promotes OS progression in vitro and in vivo by activating KDM3A-mediated SOX9 promoter demethylation, which may provide a potential therapeutic mechanism for OS.

Leptin receptor antagonist attenuates experimental autoimmune thyroiditis in mice by regulating Treg/Th17 cell differentiation

Leptin has been found to be involved in the development and progression of many autoimmune diseases. As an organ-specific autoimmune disease, the pathogenesis of Hashimoto's thyroiditis has not been fully elucidated. It has been reported that serum leptin level is increased in Hashimoto's thyroiditis, but other studies have not shown any difference. We replicated a mouse model of experimental autoimmune thyroiditis (EAT) with a high-iodine diet and found that injection of the leptin receptor antagonist Allo-aca reduced thyroid follicle destruction and inflammatory cell infiltration in EAT mice, and thyroxine and thyroid autoimmune antibody levels. Further investigation revealed that Allo-aca promotes the differentiation of Treg cells and inhibits the differentiation of Th17 cells. We believe that Allo-aca can alter the differentiation of Treg/Th17 cells by inhibiting the leptin signaling pathway, thereby alleviating thyroid injury in EAT mice. Interfering with the leptin signaling pathway may be a novel new approach to treat treating and ameliorating Hashimoto's thyroiditis.

Synthesis and Antiproliferative Activity of Ester Derivatives of Mogrol through JAK2/STAT3 Pathway

In attempt to enhance the antiproliferative activity of mogrol, two series of ester derivatives modified at C₃ -OH and C₁₁ -OH were designed and synthesized. The activity against human cancer cells including A549, NCI-H460 and CNE1 was screened by Cell Counting Kit-8 (CCK8) assay. According to the results, modifications of the mogrol core through introduction of different ester scaffolds drastically improved the cytotoxicity, and some of the derivatives exhibited even higher activity than the positive drug. Among them, compound M2h exhibited nearly 4 times more cytotoxic than 5-Fu against CNE1 cells, derivative M6c showed ten times higher activity with the IC₅₀ value of 10.59 μM than mogrol against NCI-H460 cells, and compound M6a which contained one 1,2,3-triazole motif showed the strongest activity with an three folds lower IC₅₀ value than mogrol. Furthermore, the most potent compound M2h could lead to cell cycle arrest at G2 phase on CNE1 cell lines and M6a induced G1 phase arrest on A549 cell lines. It was noteworthy that both M2h and M6a regulated signal transducer and activator of transcription 3 (STAT3) signal pathway through inhibiting phosphorylation of Janus Kinase 2 (JAK2) and STAT3, and simultaneously increasing the protein level of downstream cyclin p21.

Genistein-3'-sodium sulfonate ameliorates cerebral ischemia injuries by blocking neuroinflammation through the α7nAChR-JAK2/STAT3 signaling pathway in rats

BACKGROUND

Neuroinflammation plays a pivotal role in the acute progression of cerebral ischemia/reperfusion injury (I/RI). We previously reported that genistein-3'-sodium sulfonate (GSS), a derivative from the extract of the phytoestrogen genistein (Gen), protects cortical neurons against focal cerebral ischemia. However, the molecular mechanism underlying the neuroprotective effects exerted by GSS remains unclear.

PURPOSE

The present study focused on the anti-inflammatory effects of GSS following I/RI in rats.

STUDY DESIGN

Randomized controlled trial.

METHODS

The tMCAO rat model and LPS-stimulated BV2 in vitro model were used. Longa's scare was used to observe neurological function. TTC staining and Nissl staining were used to evaluate brain injury. ELISA, qRT-PCR, Western blotting and immunofluorescent staining methods were used to detect cytokine concentration, mRNA level, protein expression and location.

RESULTS

GSS treatment improves neurological function, reduces the volume of cerebral infarction, attenuates proinflammatory cytokines and inactivates the phosphorylation of JAK2 and STAT3 in I/RI rats. Furthermore, GSS increased the expression of α7nAChR. More importantly, the neuroprotective, anti-inflammatory and inhibiting JAK2/STAT3 signaling pathway effects of GSS were counteracted in the presence of alpha-bungarotoxin (α-BTX), an α7nAChR inhibitor, suggesting that α7nAChR is a potential target associated with the anti-inflammatory effects of GSS in the I/RI rats. GSS also inhibited BV2 cells from releasing IL-1β via the α7nAChR pathway after LPS stimulation.

CONCLUSION

GSS protects against cerebral I/RI through the expression of α7nAChR and inhibition of the JAK2/STAT3 pathway. Our findings provide evidence for the role of the cholinergic anti-inflammatory pathway in neuroinflammation and uncover a potential novel mechanism for GSS treatment in ischemic stroke. The downstream signals of GSS, α7nAChR- JAK2/STAT3 could also be potential targets for the treatment of I/RI.

GPER mediates the IL6/JAK2/STAT3 pathway involved in VEGF expression in swine ovary GCs

Vascular endothelial growth factor (VEGF) plays a pivotal role in angiogenesis in ovaries, particularly during follicular development and ovulation. Interleukin-6 (IL-6) is one of the major pro-inflammatory factors that are involved in the angiogenesis process physiologically and pathologically. Previous studies have shown that 17β-estradiol (E2) stimulates VEGF expression by upregulating hypoxia-inducible factor 1α (HIF-1α) in many cell types, and the high level of E2 causes an inflammatory-like microenvironment before ovulation. However, whether IL-6 signaling is involved in E2-regulating VEGF expression in swine granulosa cells (GCs) is still unknown. In this study, we found the estrogen membrane receptor, G-protein-coupled estrogen receptor 1 (GPER), was expressed in swine GCs, and the expression level of GPER, HIF-1α, and VEGF increased with follicular development. In vitro study showed that E2, ICI182780, and GPER agonist (G1) promoted the expressions of HIF-1α and VEGF in swine GCs, while GPER antagonist (G15) inhibited the stimulating effect of E2 and G1. Meanwhile, G15 inhibited the stimulating effect of E2 and G1 on IL-6 mRNA expression and secretion. Furthermore, IL-6 antibody and AG490 (JAK2/STAT3 inhibitor) attenuated G1-induced HIF-1α and VEGF expression. In conclusion, this study revealed how estrogen-induced HIF-1α and VEGF expressions in swine GCs are mediated through GPER-derived IL-6 secretion leading to JAK2/STAT3 activation.

Effect of profilin-1 on the asymmetric dimethylarginine-induced vascular lesion-associated hypertension

Previous studies have demonstrated that the levels of asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide (NO) synthesis, are strongly associated with hypertension, diabetes, and cardiovascular diseases. Profilin-1, an actin-binding protein, has been documented to be involved in endothelial injury and in the proliferation of vascular smooth muscle cells resulting from hypertension. However, the role of profilin-1 in ADMA-induced vascular injury in hypertension remains largely unknown. Forty healthy subjects and forty-two matched patients with essential hypertension were enrolled, and the related indexes of vascular injury in plasma were detected. Rat aortic smooth muscle cells (RASMCs) were treated with different concentrations of ADMA for different periods of time and transfected with profilin-1 small hairpin RNA to interrupt the expression of profilin-1. To determine the role of the Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) pathway, RASMCs were pretreated with AG490 or rapamycin. The expression of profilin-1 was tested using real-time polymerase chain reaction (PCR) and western blot analysis. Cell proliferation was measured by flow cytometry and 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazoliumbromide assays. Compared with healthy subjects, the levels of ADMA and profilin-1 were markedly elevated in hypertensive individuals, while the levels of NO were significantly decreased (p < 0.05). In vitro, studies showed ADMA-induced profilin-1 expression in a concentration- and time-dependent manner in RASMCs (p < 0.05), concomitantly with promoting the proliferation of RASMCs. Furthermore, ADMA-mediated proliferation of RASMCs and upregulation expression of profilin-1 were inhibited by blockade of the JAK2/STAT3 pathway or knockdown of profilin-1. Profilin-1 implicated in the ADMA-mediated vascular lesions in hypertension.

Modified citrus pectin prevents isoproterenol-induced cardiac hypertrophy associated with p38 signalling and TLR4/JAK/STAT3 pathway

Modified citrus pectin (MCP) is a specific inhibitor of galectin-3 (Gal-3) that is regarded as a new biomarker of cardiac hypertrophy, but its effect is unclear. The aim of this study is to investigate the role and mechanism of MCP in isoproterenol (ISO)-induced cardiac hypertrophy. Rats were injected with ISO to induce cardiac hypertrophy and treated with MCP. Cardiac function was detected by ECG and echocardiography. Pathomorphological changes were evaluated by the haematoxylin eosin (H&E) and wheat germ agglutinin (WGA) staining. The hypertrophy-related genes for atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and β-myosin heavy chain (β-MHC), and the associated signal molecules were analysed by qRT-PCR and western blotting. The results show that MCP prevented cardiac hypertrophy and ameliorated cardiac dysfunction and structural disorder. MCP also decreased the levels of ANP, BNP, and β-MHC and inhibited the expression of Gal-3 and Toll-like receptor 4 (TLR4). Additionally, MCP blocked the phosphorylation of Janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3), but it promoted the phosphorylation of p38. Thus, MCP prevented ISO-induced cardiac hypertrophy by activating p38 signalling and inhibiting the Gal-3/TLR4/JAK2/STAT3 pathway.

Discovery of 1,8-naphthalidine derivatives as potent anti-hepatic fibrosis agents via repressing PI3K/AKT/Smad and JAK2/STAT3 pathways

Liver fibrosis is one of the most common pathological consequences of chronic liver diseases (CLD). To develop effective antifibrotic strategies, a novel class of 1-(substituted phenyl)-1,8-naphthalidine-3-carboxamide derivatives were designed and synthesized. By means of the collagen type I α 1 (COL1A1)-based screening and cytotoxicity assay in human hepatic stellate cell (HSC) line LX-2, seven compounds were screened out from total 60 derivatives with high inhibitory effect and relatively low cytotoxicity for further COL1A1 mRNA expression analysis. It was found that compound 17f and 19g dose-dependently inhibited the expression of fibrogenic markers, including α-smooth muscle actin (α-SMA), matrix metalloprotein 2 (MMP-2), connective tissue growth factor (CTGF) and transforming growth factor β1 (TGFβ1) on both mRNA and protein levels. Further mechanism studies indicated that they might suppress the hepatic fibrogenesis via inhibiting both PI3K/AKT/Smad and non-Smad JAK2/STAT3 signaling pathways. Furthermore, 19g administration attenuated hepatic histopathological injury and collagen accumulation, and reduced fibrogenesis-associated protein expression in liver tissues of bile duct ligation (BDL) rats, showing significant antifibrotic effect in vivo. These findings identified 1,8-naphthalidine derivatives as potent anti-hepatic fibrosis agents, and provided valuable information for further structure optimization.

The effects of hyperuricemia on endothelial cells are mediated via GLUT9 and the JAK2/STAT3 pathway

BACKGROUND

Uric acid (UA) transporters mediate the uptake and outflow of UA, and are greatly involved in the control of UA concentrations. Glucose transporter 9 (GLUT9), one of the UA transporters, has been confirmed to be expressed in human umbilical vein endothelial cells (HUVECs). This study aimed to characterize GLUT9's effect on intracellular UA accumulation in HUVECs in a high-UA environment and to explore the mechanism of cellular dysfunction.

METHODS AND RESULTS

HUVECs were treated with UA to establish a model of cellular dysfunction. Then, UA uptake, GLUT9 expression and endothelial nitric oxide synthase (eNOS) and reactive oxygen species (ROS) amounts were measured. UA uptake was concentration- and time-dependent, and UA treatment significantly reduced nitric oxide (NO) levels and eNOS activity. UA also upregulated pro-inflammatory molecules and GLUT9, and increased intracellular ROS amounts in HUVECs. GLUT9 knockdown reduced UA uptake and ROS content, but antioxidant treatment did not reduce GLUT9 expression. To assess the function of JAK2/STAT3 signaling, HUVECs were treated with UA, and the phosphorylation levels of JAK2, STAT3, IL-6 and SOCS3 were increased by a high concentration of UA. In addition, GLUT9 knockdown reduced the phosphorylation of JAK2/STAT3 intermediates and increased p-eNOS amounts.

CONCLUSIONS

GLUT9 mediated the effects of high UA levels on HUVECs by increasing the cellular uptake of UA, activating JAK2/STAT3 signaling, and reduced the production of active eNOS and NO in HUVECs.

A curcumin analog GL63 inhibits the malignant behaviors of hepatocellular carcinoma by inactivating the JAK2/STAT3 signaling pathway via the circular RNA zinc finger protein 83/microRNA-324-5p/cyclin-dependent kinase 16 axis

BACKGROUND AND AIM

(1E,4E)-1,5-bis(2-bromophenyl) penta-1,4-dien-3-one (GL63) is a curcumin analog that can protect against carcinogenesis in hepatocellular carcinoma (HCC). The aim of this study was to explore the molecular mechanism of GL63 in HCC.

METHODS

Cell viability was examined by cell counting kit-8 (CCK-8) assay. Circular RNA zinc finger protein 83 (circZNF83), microRNA-324-5p (miR-324-5p), and cyclin-dependent kinase 16 (CDK16) levels were measured via the quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation was assessed using colony formation assay. Flow cytometry was performed for detecting cell cycle and apoptosis. Protein analysis was conducted by western blot. Cell migration and invasion were determined using transwell assay. Target relation was analyzed using dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. The function of GL63 in vivo was researched by xenograft model in mice.

RESULTS

GL63 inhibited the circZNF83 expression in HCC cells. CircZNF83 overexpression attenuated the inhibitory effects of GL63 on HCC cell growth, cell cycle progression, migration, and invasion but the promoting effect on cell apoptosis. CircZNF83 served as a sponge of miR-324-5p and circZNF83/miR-324-5p axis was involved in the functional regulation of GL63 in HCC progression. Moreover, CDK16 was a downstream target of miR-324-5p and circZNF83 could regulate the CDK16 expression by sponging miR-324-5p. The anti-tumor function of GL63 was also related to the miR-324-5p/CDK16 axis. In addition, GL63 inactivated the JAK2/STAT3 pathway via downregulating circZNF83 to mediate the miR-324-5p/CDK16 axis. GL63 also repressed tumor growth in vivo through the circZNF83/miR-324-5p/CDK16-mediated JAK2/STAT3 signal inhibition.

CONCLUSION

This study suggested GL63 impeded the HCC development by blocking the JAK2/STAT3 signaling pathway via mediating the circZNF83/miR-324-5p/CDK16 axis.

Tilianin inhibits the human ovarian cancer (PA-1) cell proliferation via blocking cell cycle, inducing apoptosis and inhibiting JAK2/STAT3 signaling pathway

Ovarian cancer is one of the deadliest gynecologic malignancies and is the seventh leading cause of mortalities and morbidities globally. Although there are various therapeutic strategies, a major challenge for scientific community is to come up with effective strategy to treat ovarian cancer. Tilianin, a polyphenol flavonoid is well known for its extensive biological actions like cardioprotective, neuroprotective, anti-oxidant, anti-inflammatory, anti-diabetic and anti-tumor properties. The current study is designed to investigate the anti-cancer action of Tilianin in ovarian cancer (PA-1) cells. The findings of this study revealed that Tilianin treatment results in significant and concentration dependent decrease in cell viability. The growth inhibiting action of Tilianin is associated with apoptosis which was confirmed by DAPI and AO/EtBr staining. The Tilianin-triggered apoptosis in PA-1 cells was correlated with elevated generation of ROS, loss of mitochondrial membrane potential, alterations in pro-apoptotic (upregulated mRNA expression of Bax) and anti-apoptotic (downregulated mRNA expression of Bcl2) factors and activation of caspase-8, −9 and −3. Cell cycle analysis revealed that Tilianin treatment prevented G1/S transition through reduced mRNA expression of cyclin D1. Additionally, the findings of this study also showed Tilianin inhibited JAK2/STAT3 signaling (downregulated expression of pJAK2, JAK2, pSTAT3, and STAT3) with no change in mRNA expression level of ERK indicating its non-involvement in the apoptotic and/or growth inhibition of ovarian cancer cells. In conclusion, the findings of this exploration provided clear evidence of anti-cancer effects of Tilianin in PA-1 cells through its anti-proliferative action, ability to induce apoptosis both through extrinsic and intrinsic pathways, cell cycle (G1/S) arrest and JAK2/STAT3 signaling inhibition.

Study on the effect of Mongolian medicine Qiwei Qinggan Powder on hepatic fibrosis through JAK2/STAT3 pathway

This research aimed to evaluate the antihepatic fibrosis effect and explore the mechanism of Qiwei Qinggan Powder (QGS-7) in vivo and in vitro. Carbon tetrachloride (CCl4)-treated rats and hepatic stellate cells (HSCs) were used. QGS-7 treatment significantly improved the liver function of rats as indicated by decreased serum enzymatic activities of alanine aminotransferase, aspartate transaminase, and alkaline phosphatase. Meanwhile, the hydroxyproline of liver was significantly decreased. Histopathological results indicated that QGS-7 alleviated liver damage and reduced the formation of fibrosis septa. Moreover, QGS-7 significantly attenuated expressions of Alpha smooth muscle actin, Collagen I, Janus kinase 2 (JAK2), phosphorylation-JAK2, signal transducer and activator of transcription 3 (STAT3), phosphorylation-STAT3 in the rat hepatic fibrosis model. QGS-7 inhibited HSC proliferation and promoted it apoptosis. QGS-7 may affect hepatic fibrosis through JAK2/STAT3 signaling pathway so as to play an antihepatic fibrosis role.

RANKL expression of primary osteoblasts is enhanced by an IL-17-mediated JAK2/STAT3 pathway through autophagy suppression

Objective: Interleukin-17 (IL-17), produced by T helper (Th)-17 cells, is a potent regulator of bone homeostasis. Osteoblasts are key cells that orchestrate inflammatory bone destruction and bone remodeling. This study examines the effect of different concentrations of IL-17 on osteogenesis and receptor activator of nuclear factor-kappa B ligand (RANKL) expression of primary osteoblasts.Methods: First, the growth of primary osteoblasts was evaluated. Second, we assessed the effects of IL-17 on the level of autophagy and the related Janus activated kinase 2 (JAK2) and downstream signal transducer and activator of transcription 3 (STAT3) signaling pathway. Next, osteogenic activity in different concentrations of IL-17 was tested. Finally, the specific JAK2/STAT3 signaling pathway inhibitor AG490 and autophagy inhibitor 3-MA were used to investigate the involvement of this pathway and autophagy in IL-17-induced regulation of RANKL expression.Results: Initially, we found that IL-17 treatment promoted growth of osteoblasts in a time- and dose-dependent manner. Next, we showed that low levels of IL-17 promoted autophagy activity, whereas the opposite was observed at high levels of IL-17. Moreover, high levels of IL-17 activated the JAK2/STAT3 signaling pathway, although this effect was reversed by upregulation of autophagy. Furthermore, our findings indicated that high concentrations of IL-17 promoted the differentiation, calcification, and RANKL expression of murine osteoblasts via activation of the JAK2/STAT3 pathway. Importantly, downregulation of autophagy at high IL-17 concentrations further enhanced RANKL expression via suppressing the JAK2/STAT3 cascade.Conclusion: Overall, our findings demonstrate, for the first time, that IL-17 modulates RANKL expression of osteoblasts through an autophagy-JAK2-STAT3 signaling pathway, thus affecting bone metabolism.