Previous studies have shown that scutellarin inhibits the excessive activation of microglia, reduces neuronal apoptosis, and exerts neuroprotective effects. However, whether scutellarin regulates activated microglia-mediated neuronal apoptosis and its mechanisms remains unclear. This study aimed to investigate whether scutellarin can attenuate PC12 cell apoptosis induced by activated microglia via the JAK2/STAT3 signalling pathway. Microglia were cultured in oxygen-glucose deprivation (OGD) medium, which acted as a conditioning medium (CM) to activate PC12 cells, to investigate the expression of apoptosis and JAK2/STAT3 signalling-related proteins. We observed that PC12 cells apoptosis in CM was significantly increased, the expression and fluorescence intensity of the pro-apoptotic protein Bax and apoptosis-related protein cleaved caspase-3 were increased, and expression of the anti-apoptotic protein B-cell lymphoma-2 (Bcl-2) was decreased. Phosphorylation levels and fluorescence intensity of the JAK2/STAT3 signalling pathway-related proteins JAK2 and STAT3 decreased. After treatment with scutellarin, PC12 cells apoptosis as well as cleaved caspase-3 and Bax protein expression and fluorescence intensity decreased. The expression and fluorescence intensity of Bcl-2, phosphorylated JAK2, and STAT3 increased. AG490, a specific inhibitor of the JAK2/STAT3 signalling pathway, was used. Our findings suggest that AG490 attenuates the effects of scutellarin. Our study revealed that scutellarin inhibited OGD-activated microglia-mediated PC12 cells apoptosis which was regulated via the JAK2/STAT3 signalling pathway.

Epilepsy ranks fourth among neurological diseases, featuring spontaneous seizures and behavioural and cognitive impairments. Although anti-epileptic drugs are currently available clinically, 30 % of epilepsy patients are still ineffective in treatment and 52 % of patients experience serious adverse reactions. In this work, the neuroprotective effect of α-linolenic acid (ALA, a nutrient) in mice and its potential molecular mechanisms exposed to pentylenetetrazol (PTZ) was assessed. The mice were injected with pentetrazol 37 mg/kg, and ALA was intra-gastrically administered for 40 d. The treatment with ALA significantly reduced the overall frequency of epileptic seizures and improved the behaviour impairment and cognitive disorder caused by pentetrazol toxicity. In addition, ALA can not only reduce the apoptosis rate of brain neurons in epileptic mice but also significantly reduce the content of brain inflammatory factors (IL-6, IL-1 and TNF-α). Furthermore, we predicted that the possible targets of ALA in the treatment of epilepsy were JAK2 and STAT3 through molecular docking. Finally, through molecular docking and western blot studies, we revealed that the potential mechanism of ALA ameliorates PTZ-induced neuron apoptosis and neurological impairment in mice with seizures by down-regulating the JAK2/STAT3 pathway. This study aimed to investigate the anti-epileptic and neuroprotective effects of ALA, as well as explore its potential mechanisms, through the construction of a chronic ignition mouse model via intraperitoneal PTZ injection. The findings of this research provide crucial scientific support for subsequent clinical application studies in this field.

Endometrial cancer is a malignant tumour with a high incidence and mortality rate, and obesity is one of the most significant risk factors for the disease. However, it remains unclear whether leptin affects cell activity, proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT).
Samples of endometrial cancer tissue were obtained from clinical patients and nude mice Enzyme-linked immunosorbent assays (ELISAs) were performed to assess leptin levels. Western blotting, immunohistochemical (IHC) and immunofluorescence (IF) analyses were conducted to detect EMT, JAK2/STAT3 signalling pathway proteins, and cell proliferation biomarkers. Cell Counting Kit-8 (CCK-8) assays, 5-ethynyl-2\'-deoxyuridine (EdU) staining, and Transwell assays were used to evaluate cell activity, proliferation, migration, and invasion, respectively.
ELISA, western blot and immunohistochemistry (IHC) analyses showed that leptin was highly expressed, and the JAK2/STAT3 signalling pathway was activated in endometrial cancer patients. Cell-based experiments showed that adipocytes secreted leptin, which increased the levels of leptin, and also promoted cell migration and invasion, EMT transition, and cell activity and proliferation. Leptin accelerated cell progression and promoted EMT via the JAK2/STAT3 signalling pathway in a dose-dependent manner. The tumour-promoting effect of leptin on endometrial cancer cells was further verified by in vivo experiments, in which leptin promoted tumour growth and activated the JAK2/STAT3 signalling pathway.
Leptin secreted by adipocytes promotes EMT transition and endometrial cancer progression via the JAK2/STAT3 signalling pathway in a dose-dependent manner.Highlights Endometrial cancer patients have high levels of leptinLeptin promotes EMT transition via the JAK2/STAT3 signalling pathwayLeptin promotes endometrial cancer progression via the JAK2/STAT3 signalling pathwayLeptin promotes endometrial cancer in a dose-dependent manner.

OBJECTIVE: To explore the regulation of SOCS3 in the JAK2/STAT3 pathway during vocal fold fibroblast activation after vocal fold injury.
METHODS: Normal vocal fold fibroblasts (VFFs), injured VFFs, and simulated injured VFFs (normal VFFs supplemented with transforming growth factor beta [TGF-β]) were treated with a JAK2 inhibitor (AG490), and SOCS3 was overexpressed in each group. Type I collagen (COL1), α-smooth muscle actin (α-SMA), SOCS3, JAK2, and STAT3 were detected using immunofluorescence, quantitative real-time polymerase chain reaction (qRT-PCR), and western blotting.
RESULTS: Compared with normal VFFs, expression of SOCS3 was lower, but p-JAK/p-STAT3 and JAK2/STAT3 were higher in injured and simulated injured VFFs. After the addition of AG490, COL1 and α-SMA expressions did not change significantly in normal VFFs but was significantly decreased in the other two groups. The protein and mRNA expression levels of SOCS3 were significantly increased, while those of p-JAK/p-STAT3 and JAK2/STAT3 were significantly decreased. When SOCS3 was overexpressed, the COL1 and α-SMA expression levels in normal VFFs were not altered significantly, whereas they were significantly decreased in injured and simulated injured VFFs. The expression of p-JAK2/p-STAT3 significantly decreased when SOCS3 was overexpressed in injured and simulated injured VFFs.
CONCLUSIONS: SOCS3 may regulate the activation of JAK2/STATA3 pathway after vocal fold injury. In addition, SOCS3 may inhibit excessive activation of vocal fold fibroblasts by downregulating JAK2/STAT3 in the early stages of vocal fold injury.

Pancreatic cancer is one of the most aggressive solid malignancies, as it has a 5-year survival rate of less than 10%. The growth and invasion of pancreatic cancer cells into normal tissues and organs make resection and treatment difficult. Finding an effective chemotherapy drug for this disease is crucial. In this study, we selected the tetracyclic triterpenoid compound cucurbitacin I, which may be used as a potential therapeutic drug for treating pancreatic cancer. First, we found that cucurbitacin I inhibited pancreatic cancer proliferation in a dose-time dependent manner. Further studies have shown that cucurbitacin I blocks the cell cycle of pancreatic cancer in the G2/M phase and induces cell apoptosis. In addition, under the action of the compound, the invasion ability of cells was greatly reduced and markedly impaired the growth of pancreatic tumour xenografts in nude mice. Furthermore, the decrease in pancreatic cancer cell proliferation caused by cucurbitacin I appeared to involve JAK2/STAT3 signalling pathway inhibition, and the use of JAK2/STAT3 activators effectively restored the inhibition. In conclusion, our research may provide a basis for the further development of pancreatic cancer treatment drugs.

BACKGROUND: Trophoblast dysfunction during pregnancy is fundamentally involved in preeclampsia. Several studies have revealed that human chorionic villous mesenchymal stem cells (CV-MSCs) could regulate trophoblasts function.
RESULTS: To understand how human chorionic villous mesenchymal stem cells (CV-MSCs) regulate trophoblast function, we treated trophoblasts with CV-MSC supernatant under hypoxic conditions. Treatment markedly enhanced proliferation and invasion and augmented autophagy. Transcriptome and pathway analyses of trophoblasts before and after treatment revealed JAK2/STAT3 signalling as an upstream regulator. In addition, STAT3 mRNA and protein levels increased during CV-MSC treatment. Consistent with these findings, JAK2/STAT3 signalling inhibition reduced the autophagy, survival and invasion of trophoblasts, even in the presence of CV-MSCs, and blocking autophagy did not affect STAT3 activation in trophoblasts treated with CV-MSCs. Importantly, STAT3 overexpression increased autophagy levels in trophoblasts; thus, it positively regulated autophagy in hypoxic trophoblasts. Human placental explants also proved our findings by showing that STAT3 was activated and that LC3B-II levels were increased by CV-MSC treatment.
CONCLUSIONS: In summary, our data suggest that CV-MSC-dependent JAK2/STAT3 signalling activation is a prerequisite for autophagy upregulation in trophoblasts.

MicroRNA plays an integral role in the development of atherosclerosis. Our study aimed to investigate the roles of miR-599 in lipopolysaccharide (LPS)-induced endothelial damage in human umbilical vein endothelial cells (HUVECs). HUVECs were transfected with a miR-599 mimic and negative control, and then exposed to LPS. The expression of miR-599 was detected by quantitative real time-polymerase chain reaction (RT-qPCR). Cell viability was analyzed by CCK-8 assay and trypan blue exclusion assay; the formation of DNA fragments was tested by Cell Death Detection ELISA Plus kit; the incidence of apoptosis was detected by flow cytometry; the expression of p53 and cleaved-caspase 3 (c-caspase 3) was evaluated by western blot. Moreover, the mRNA levels and concentrations of tumour necrosis factor (TNF)-α, interleukin (IL)-6, ICAM-1 and VCAM-1 were assayed by RT-qPCR and ELISA. The results showed that overexpression of miR-599 increased cell viability, reduced DNA fragments, the incidence of apoptosis, as well as the protein levels of p53 and c-caspase 3 in the presence of LPS. TNF-α, IL-6, ICAM-1 and VCAM-1 mRNA levels and concentrations were also decreased upon miR-599 upregulation. In addition, the dual luciferase reporter assay demonstrated that ROCK1 is a direct target of miR-599. MiR-599 overexpression inhibited ROCK1 expression. Induced expression of ROCK1 reversed the roles of miR-599 in apoptosis and inflammation. The gain function of miR-599 function inhibited activation of the JAK2/STAT3 signalling pathway, which was abrogated by overexpression of ROCK1. Taken together, our results indicate that miR-599 attenuates LPS-caused cell apoptosis and inflammatory responses through the JAK2/STAT3 signalling pathway via targeting ROCK1.

OBJECTIVE: The shortage of donor hearts could be alleviated with the use of the allografts from donation after circulatory death (DCD). Here, we evaluated the protective effect of melatonin on myocardial ischemia/reperfusion (MI/R) injury in a DCD heart model after ex vivo perfusion.
METHODS: Donor hearts were harvested from DCD model rats pre-treated with or without melatonin and subjected to 30 min of ex vivo perfusion, followed by transplantation. Tissue samples were obtained at 3, 12, and 24 h after heart transplantation. Myocardial oedema was evaluated based on the water content and wet/dry ratio, while inflammation was examined with hematoxylin & eosin staining. The expression levels of matrix metalloproteinase-9, interleukin-6, and tumour necrosis factor-α were evaluated. Oxidative stress level was determined from the content of malondialdehyde, activities of superoxide dismutase and glutathione peroxidase, and expression of Nrf2, NQO1 and cytochrome-C. Myocardial apoptosis was detected with TUNEL assay and measurement of the expression levels of Bax, Bcl-2, caspase-3, and cleaved caspase-3. The activation of the JAK2/STAT3 signalling pathway was evaluated by determining the levels of p-JAK2 and p-STAT3.
RESULTS: Melatonin pre-treatment protected the heart from MI/R by reducing myocardial oedema and inflammation, attenuating oxidative stress, and decreasing myocardial apoptosis. Furthermore, the JAK2/STAT3 signalling pathway was activated after melatonin treatment during MI/R. The protective effects of melatonin were abolished by AG490.
CONCLUSIONS: Melatonin pre-treatment protected the heart from MI/R in a DCD heart model after ex vivo perfusion. Melatonin exerted cardioprotective effects through the activation of the JAK2/STAT3 signalling pathway.

OBJECTIVE: This study aimed to investigate the anti-inflammatory effects of a novel spirocyclopiperazinium salt compound LXM-15, and explore the underlying mechanisms.
METHODS: Xylene-induced mouse ear oedema and carrageenan-induced rat paw oedema tests were used to evaluate the anti-inflammatory effects of LXM-15. The protein levels of TNF-α, IL-6, phosphorylation of Janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3) were detected by ELISA or Western blot analysis. Additionally, receptor blocking test was performed to explore the possible target.
RESULTS: Intragastric administration with LXM-15 (2, 1, 0.5 mg/kg in mice, and 6, 3, 1.5 mg/kg in rats) produced distinct anti-inflammatory effects in vivo, the highest inhibition percentage was 60 and 52%, respectively (P < 0.01). Following treatment with LXM-15 (6 mg/kg, i.g.), the levels of TNF-α and IL-6 in the rats paws were attenuated by 40 and 41%; and the phosphorylation of JAK2 and STAT3 was restrained by 35 and 45%, respectively (P < 0.01). All effects of LXM-15 were blocked by pretreatment with methyllycaconitine citrate or tropicamide.
CONCLUSIONS: This study provides the first report that the spirocyclopiperazinium salt compound LXM-15 displays considerable anti-inflammatory effects. The underlying mechanism may be through activating the peripheral α7 nicotinic acetylcholine receptor and M4 muscarinic acetylcholine receptor, leading to the inhibition of the JAK2/STAT3 signalling pathway, eventually resulting in the reduction of TNF-α and IL-6.