A peptide encoded by upstream open reading frame of MYC binds to tropomyosin receptor kinase B and promotes glioblastoma growth in mice.

MYC promotes tumor growth through multiple mechanisms. Here, we show that, in human glioblastomas, the variant MYC transcript encodes a 114-amino acid peptide, MYC pre-mRNA encoded protein (MPEP), from the upstream open reading frame (uORF) MPEP. Secreted MPEP promotes patient-derived xenograft tumor growth in vivo, independent of MYC through direct binding, and activation of tropomyosin receptor kinase B (TRKB), which induces downstream AKT-mTOR signaling. Targeting MPEP through genetic ablation reduced growth of patient-derived 4121 and 3691 glioblastoma stem cells. Administration of an MPEP-neutralizing antibody in combination with a small-molecule TRKB inhibitor reduced glioblastoma growth in patient-derived xenograft tumor-bearing mice. The overexpression of MPEP in surgical glioblastoma specimens predicted a poor prognosis, supporting its clinical relevance. In summary, our results demonstrate that tumor-specific translation of a MYC-associated uORF promotes glioblastoma growth, suggesting a new therapeutic strategy for glioblastoma.

Effects and mechanisms of Salvia miltiorrhiza Bunge extract on myocardial cell apoptosis in rat heart failure model.

PURPOSE: This work aimed to investigate the effects of Tanshinone IIA (Tan IIA) on myocardial cell (MC) apoptosis in a rat model of heart failure (HF). METHODS: Tan IIA was extracted from Salvia miltiorrhiza Bunge (SMB) using an ethanol reflux method. Fifty rats were randomly divided into five groups: sham (no treatment), mod (HF model establishment), low dose (LD: 0.1 mL/kg Tan IIA), medium dose (MD: 0.3 mL/kg Tan IIA), and high dose (HD: 0.5 mL/kg Tan IIA), with 10 rats in each group. The effects of different doses of Tan IIA on cardiac function, MC apoptosis, and the levels of proteins associated with the PI3K/Akt/mTOR signaling pathway were compared. RESULTS: Mod group showed a significant decrease in systolic arterial pressure, mean arterial pressure, heart rate, left ventricular systolic pressure, left ventricular ejection fraction, left ventricular fractional shortening, and the levels of p-PI3K, p-Akt, and p-mTOR proteins versus sham group (p < 0.05). Additionally, the left ventricular end-diastolic diameter (LVIDd), end-systolic diameter, diastolic pressure, and MC apoptosis were significantly increased (p < 0.05). LD, MD, and HD groups exhibited significant improvements across various indicators of cardiac function and MC apoptosis versus mod group (p < 0.05). CONCLUSIONS: Tan IIA may improve cardiac function and inhibit MC apoptosis in rats with HF by modulating the PI3K/Akt/mTOR signaling pathway.

Diosgenin Alleviates Obesity-Induced Insulin Resistance by Modulating PI3K/Akt Signaling Pathway in Mice Fed a High-Fat Diet.

Obesity is a global medical issue that can be effectively treated by relieving adipose inflammation and subsequent insulin resistance. Diosgenin (DIOS) has various effects as a steroidal saponin in inflammatory disorders. This study explored the effects and mechanism of DIOS on adipose inflammation and insulin sensitivity, both in silico and in vivo. The high-fat diet-induced obesity model in C57BL/6 mice was divided into five groups: normal chow (NC), high-fat diet (HFD), HFD with atorvastatin 10 mg/kg (AT), HFD with DIOS 100 mg/kg (DIOS 100), and HFD with DIOS 200 mg/kg (DIOS 200). Each group underwent an oral intervention for seven weeks. DIOS significantly suppressed weight gain in the body, liver, and epididymal fat pads. Additionally, it significantly improved fasting glucose and insulin levels, homeostatic model assessment of insulin resistance (HOMA-IR), and oral glucose tolerance test results, and reduced the proportion of total and M1 adipose tissue macrophages. Significant changes were shown in mRNA expression of janus kinase 2 (JAK2), insulin receptor (INRS), insulin receptor substrate 1 (IRS-1), phosphatidylinositol 3-kinase (PI3K), and protein kinase B (Akt), all of which exhibited high binding affinity in the in silico. Safety indices, including aspartate aminotransferase (AST), alanine transaminase (ALT), and creatinine level indicated the preventive effects of DIOS. In conclusion, DIOS improves insulin resistance and obesity-associated inflammation via the PI3K/Akt signaling pathway.

Spatially restricted ecto-5'-nucleotidase expression promotes the growth of uterine leiomyomas by modulating Akt activity.

Found in as many as 80% of women, uterine leiomyomas are a frequent cause of abnormal uterine bleeding, pelvic pain, and infertility. Despite their significant clinical impact, the mechanisms responsible for driving leiomyoma growth remain poorly understood. After obtaining IRB permission, expression of ecto-5'-nucleotidase (NT5E, CD73) was assessed in matched specimens of myometrium and leiomyoma by real-time qPCR, Western blot, and immunohistochemistry (IHC). Adenosine concentrations were measured by enzyme-linked assay. Primary cultures were used to assess the impact of adenosine and/or adenosine receptor agonists on proliferation, apoptosis, and patterns of intracellular signaling in vitro. When compared to matched specimens of healthy myometrium, uterine leiomyomas were characterized by reduced CD73 expression. Largely limited to thin-walled vascular structures and the pseudocapsule of leiomyomas despite diffuse myometrial distribution. Restricted intra-tumoral CD73 expression was accompanied by decreased levels of intra-tumoral adenosine. In vitro, incubation of primary leiomyoma cultures with adenosine or its hydrolysis-resistant analog 2-chloro-adenosine (2-CL-AD) inhibited proliferation, induced apoptosis, and reduced proportion of myocytes in S- and G2-M phases of the cell cycle. Decreased proliferation was accompanied by reduced expression of phospho-Akt, phospho-Cdk2-Tyr15, and phospho-Histone H3. Enforced expression of the A2B adenosine receptor (ADORA2B) and ADORA2B-selective agonists similarly suppressed proliferation and inhibited Akt phosphorylation. Collectively, these observations broadly implicate CD73 and reduced extracellular concentrations of adenosine as key regulators of leiomyoma growth and potentially identify novel strategies for clinically managing these common tumors.

Nervonic acid improves fat transplantation by promoting adipogenesis and angiogenesis.

Adipose tissue engraftment has become a promising strategy in the field of regenerative surgery; however, there are notable challenges associated with it, such as resorption of 50­90% of the transplanted fat or cyst formation due to fat necrosis after fat transplantation. Therefore, identifying novel materials or methods to improve the engraftment efficiency is crucial. The present study investigated the effects of nervonic acid (NA), a monounsaturated very long­chain fatty acid, on adipogenesis and fat transplantation, as well as its underlying mechanisms. To assess this, NA was used to treat cells during adipogenesis in vitro, and the expression levels of markers, including PPARγ and CEBPα, and signaling molecules were detected through reverse transcription­quantitative PCR and western blotting. In addition, NA was mixed with fat grafts in in vivo fat transplantation, followed by analysis through Oil Red O staining, hematoxylin & eosin staining and immunohistochemistry. It was demonstrated that NA treatment accelerated adipogenesis through activation of the Akt/mTOR pathway and inhibition of Wnt signaling. NA treatment enriched the expression of Akt/mTOR signaling­related genes, and increased the expression of genes involved in angiogenesis and fat differentiation in human mesenchymal stem cells (MSCs). Additionally, NA effectively improved the outcome of adipose tissue engraftment in mice. Treatment of grafts with NA at transplantation reduced the resorption of transplanted fat and increased the proportion of perilipin­1+ adipocytes with a lower portion of vacuoles in mice. Moreover, the NA­treated group exhibited a reduced pro­inflammatory response and had more CD31+ vessel structures, which were relatively evenly distributed among viable adipocytes, facilitating successful engraftment. In conclusion, the present study demonstrated that NA may not only stimulate adipogenesis by regulating signaling pathways in human MSCs, but could improve the outcome of fat transplantation by reducing inflammation and stimulating angiogenesis. It was thus hypothesized that NA could serve as an adjuvant strategy to enhance fat engraftment in regenerative surgery.

Euphorbia helioscopia L. extract suppresses hepatitis B virus-related hepatocellular carcinoma via alpha serine/threonine-protein kinase and Caspase-3.

BACKGROUND: Hepatitis B virus (HBV)-related hepatocellular carcinoma (HBV-HCC) has poor prognosis and high mortality rate. Euphorbia helioscopia L. (EHL) is a classic Chinese medicinal herb. AIM: This study aimed to evaluate in vitro anti-HBV-HCC properties of EHL, and explore it targets in HBV-HCC based on molecular docking. METHODS: The anti-tumor effect of EHL on HBV-HCC was evaluated using the cell viability, migration, invasion, and apoptosis of Hep 3B2.1-7 and HepG2.2.15 cells. Next, network pharmacological analysis was performed to predicted the key targets of EHL against HBV-HCC. Then the prognostic targets, including RAC-alpha serine/threonine-protein kinase (AKT1) and Caspase-3 (CASP3), were verified using molecular docking and rescue experiments. RESULTS: EHL exhibited inhibitory effects on cell proliferation/migration/invasion and induced cell apoptosis. Network pharmacological analysis proposed 12 active compounds in EHL, which targeted 22 HBV-HCC-related genes. AKT1 and CASP3 were identified to be key targets for EHL against HBV-HCC. AKT1 and CASP3 had prognostic significance in liver cancer. Overexpression of AKT1 and caspase-3 inhibitor can counteract the EHL effect. CONCLUSION: EHL can exert anticancer effects on HBV-HCC by inhibiting migration/invasion, and inducing apoptosis, which may be achieved through AKT1 and CASP3.

AEBP1 restores osteoblastic differentiation under dexamethasone treatment by activating PI3K/AKT signalling.

Adipocyte enhancer-binding protein 1 (AEBP1) is closely implicated in osteoblastic differentiation and bone fracture; this research aimed to investigate the effect of AEBP1 on restoring osteoblastic differentiation under dexamethasone (Dex) treatment, and its interaction with the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway. Pre-osteoblastic MC3T3-E1 cells were cultured in osteogenic medium and treated by Dex to mimic steroid-induced osteonecrosis cellular model. They were then further transfected with control or AEBP1-overexpressed lentiviral vectors. Finally, cells were treated with the PI3K inhibitor LY294002, with or without AEBP1-overexpressed lentiviral vectors. AEBP1 expression showed a downward trend in MC3T3-E1 cells under Dex treatment in a dose-dependent manner. AEBP1-overexpressed lentiviral vectors increased relative cell viability, alkaline phosphatase (ALP) staining, Alizarin red staining and osteoblastic differentiation markers including osteocalcin (OCN), osteopontin (OPN), collagen type I alpha 1 (COL1A1), runt-related transcription factor 2 (RUNX2) and bone morphogenetic protein 2 (BMP2), but decreased cell apoptosis rate in MC3T3-E1 cells under Dex treatment; besides, AEBP1-overexpressed lentiviral vectors positively regulated p-PI3K and p-AKT expressions. Furthermore, LY294002 treatment decreased relative cell viability, Alizarin red staining, osteoblastic differentiation markers including OCN, OPN, RUNX2 and BMP, increased cell apoptosis rate and did not affect ALP staining in MC3T3-E1 cells under Dex treatment; meanwhile, LY294002 treatment weakened the effect of AEBP1 overexpression vectors on the above cell functions. AEBP1 restores osteoblastic differentiation under Dex treatment by activating the PI3K/AKT pathway.

Polyphyllin II inhibits breast cancer cell proliferation via the PI3K/Akt signaling pathway.

Paridis Rhizoma saponins (PRS) are significant components of Rhizoma Paridis and have inhibitory effects on various tumors, such as bladder, breast, liver and colon cancer. Polyphyllin II (PPII), one of the PRS, has an unclear effect on breast cancer. The present study aimed to explore the effect and mechanism of PPII in breast cancer. A network pharmacology approach was employed to predict the core components and breast cancer­related targets of PRS. Moreover, a xenograft tumor model was established to determine the anti­breast cancer effect of PPII in vivo. The viability of MDA­MB­231 cells was determined by a Cell Counting Kit­8 assay. Apoptosis was analyzed using annexin V/PI double staining. Additionally, Transwell and scratch assays were performed to evaluate invasion and migration. The potential mechanism was predicted by Kyoto Encyclopedia of Genes and Genomes enrichment analysis and molecular docking analysis and verified by western blot analysis. The effect of PPII on aerobic glycolysis in breast cancer cells was detected by lactic acid and pyruvate kits and Western blotting of glycolytic rate­limiting enzymes. Network pharmacology analysis revealed 26 core targets involved in breast cancer and that PPII was the core active component of PRS. The in vivo studies showed that PPII could inhibit the growth of breast cancer in mice. In vitro experiments confirmed that PPII induced cancer cell apoptosis and inhibited invasion and migration. Furthermore, PPII was capable of suppressing the expression of key proteins in the PI3K/Akt signaling pathway, reducing the generation of aerobic glycolytic products, and diminishing the protein expression levels of hexokinase 2 and pyruvate kinase M2. The results indicated that PPII inhibited aerobic glycolysis in breast cancer cells through the PI3K/Akt signaling pathway, thereby inhibiting breast cancer growth.

Mild therapeutic hypothermic protection activates the PI3K/AKT signaling pathway to inhibit TRPM7 and suppress ferroptosis induced by myocardial ischemia­reperfusion injury.

The present study aimed to investigate the role of PI3K­mediated ferroptosis signaling induced by mild therapeutic hypothermia (MTH), which was defined as a temperature of 34˚C, in protecting against myocardial ischemia-reperfusion (I/R) injury (MIRI). To meet this aim, H9C2 cells underwent hypoxia­reperfusion (H/R) and/or MTH. The MTT assay was used to assess cell viability, cytotoxicity was measured using a lactate dehydrogenase cytotoxicity assay, and Annexin V­FITC/PI flow cytometric analysis was used to analyze early and late cell apoptosis. In addition, 84 healthy adult male Sprague­Dawley rats were randomly divided into seven groups (n=12), and underwent I/R and various treatments. Hemodynamics were monitored, and the levels of myocardial injury marker enzymes and oxidative stress markers in myocardial tissue were measured using ELISA. The expression levels of PI3K, AKT, transient receptor potential cation channel subfamily M member 7 (TRPM7), glutathione peroxidase 4 (GPX4) and acyl­CoA synthetase long chain family member 4 (ACSL4) in animals and cells were measured using western blot analysis. These experiments revealed that MTH could effectively reduce myocardial infarct size, improve hemodynamic performance following MIRI and suppress myocardial apoptosis, thereby contributing to the recovery from H/R injury. Mechanistically, MTH was revealed to be able to activate the PI3K/AKT signaling pathway in cells, upregulating GPX4, and downregulating the expression levels of TRPM7 and ACSL4. Treatment with 2­aminoethoxydiphenyl borate (an inhibitor of TRPM7) could further strengthen the myocardial protective effects of MTH, whereas treatment with erastin (promoter of ferroptosis) and wortmannin (inhibitor of PI3K) led to the effective elimination of the myocardial protective effects of MTH. Compared with in the I/R group, the PI3K/AKT activation level and the expression levels of GPX4 were both significantly increased, whereas the expression levels of TRPM7 and ACSL4 were significantly decreased in the I/R + MTH group. Taken together, the results of the present study indicated that MTH may activate the PI3K/AKT signaling pathway to inhibit TRPM7 and suppress ferroptosis induced by MIRI.

Sirt6 ameliorates high glucose-induced podocyte cytoskeleton remodeling via the PI3K/AKT signaling pathway.

BACKGROUND: Podocyte injury plays an important role in the occurrence and progression of diabetic kidney disease (DKD), which leads to albuminuria. Cytoskeletal remodeling is an early manifestation of podocyte injury in DKD. However, the underlying mechanism of cytoskeletal remodeling has not been clarified. Histone deacetylase sirtuin6 (Sirt6) has been found to play a key role in DKD progression, and the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (PKB/AKT) pathway directly regulates the cytoskeletal structure of podocytes. Whereas, the relationship between Sirt6, the PI3K/AKT pathway and DKD progression remains unclear. METHODS: Renal injury of db/db mice was observed by PAS staining and transmission electron microscope. Expression of Sirt6 in the glomeruli of db/db mice was detected by immunofluorescence. UBCS039, a Sirt6 activator, was used to explore the renal effects of Sirt6 activation on diabetic mouse kidneys. We also downregulating Sirt6 expression in podocytes using the Sirt6 inhibitor, OSS_128167, and induced upregulation of Sirt6 using a recombinant plasmid, after which the effects of Sirt6 on high glucose (HG)-induced podocyte damage were assessed in vitro. Podocyte cytoskeletal structures were observed by phalloidin staining. The podocyte apoptotic rate was assessed by flow cytometry, and PI3K/AKT signaling activation was measured by Western blotting. RESULTS: Db/db mice exhibited renal damage including elevated urine albumin-to-creatinine ratio (ACR), increased mesangial matrix, fused podocyte foot processes, and thickened glomerular basement membrane. The expression of Sirt6 and PI3K/AKT pathway components was decreased in db/db mice. UBCS039 increased the expressions of Sirt6 and PI3K/AKT pathway components and ameliorated renal damage in db/db mice. We also observed consistent Sirt6 expression was in HG-induced podocytes in vitro. Activation of the PI3K/AKT pathway via a Sirt6 recombinant plasmid ameliorated podocyte cytoskeletal remodeling and apoptosis in HG-treated immortalized human podocytes in vitro, whereas Sirt6 inhibition by OSS_128167 accelerated HG-induced podocyte damage in vitro. CONCLUSIONS: Sirt6 protects podocytes against HG-induced cytoskeletal remodeling and apoptosis through activation of the PI3K/AKT signaling pathway. These findings provide evidence supporting the potential efficacy of Sirt6 activation as a promising therapeutic strategy for addressing podocyte injury in DKD.

Aldo-keto reductase family 1 member C3 mediates radioresistance of esophageal cancer cells through suppressing MAPK and AKT signaling.

BACKGROUND: Aldo-keto reductase family 1 member C3 (AKR1C3) is a radioresistance gene in esophageal cancer. This study aimed to investigate the signaling pathways that mediate the regulatory role of AKR1C3 in the radioresistance of esophageal cancer cells. METHODS: The protein levels of AKR1C3 in cancer tissue samples were compared between patients with radiosensitive and radioresistant esophageal cancer using immunohistochemical staining. AKR1C3-silenced stable KYSE170R esophageal cancer cells (KY170R-shAKR1C3) were established. Colony formation assay was employed to evaluate the radiosensitivity of cancer cells, while flow cytometry analysis was utilized to quantify reactive oxygen species (ROS) production in these cells. Additionally, Western blotting was conducted to determine protein expression levels. RESULTS: AKR1C3 protein exhibited significantly higher expression in radioresistant cancer tissue samples compared to radiosensitive samples. AKR1C3 silencing promoted radiosensitivity and ROS production of KYSE170R cells. At 32 h after X-ray radiation, the levels of total and phosphorylated ERK1/2, JNK, and AKT proteins were significantly elevated in KYSE170R-shAKR1C3 cells compared to untransfected KYSE170R cells. The inhibitor of AKR1C3 remarkably enhanced the radiosensitivity of KYSE170R cells. Conversely, treatment with either a MEK inhibitor or an AKT inhibitor significantly increased the radioresistance of KYSE170R-shAKR1C3 cells. CONCLUSIONS: Our results suggest that AKR1C3 mediates radioresistance of KYSE170R cells possibly through MAPK and AKT signaling.

ITGA5 is associated with prognosis marker and immunosuppression in head and neck squamous cell carcinoma.

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) is a major tumor that seriously threatens the health of the head and neck or mucosal system. It is manifested as a malignant phenotype of high metastasis and invasion caused by squamous cell transformation in the tissue area. Therefore, it is necessary to search for a biomarker that can systematically correlate and reflect the prognosis of HNSCC based on the characteristics of head and neck tumors. METHODS: Based on TCGA-HNSCC data, R software was used to analyze gene expression, correlation, Venn diagram, immune invasive and immunosuppressive phenotypes respectively. The intrinsic effect of ITGA5 on the malignant phenotype of HNSCC cells was verified by cell experiments. Immunohistochemical images from The Human Protein Atlas (THPA) database display the differences in the expression of related proteins in HNSCC tissues. Based on functional enrichment and correlation analysis, the prognostic value of ITGA5 for HNSCC was explored, and the expression level of ITGA5 may affect the chemotherapy of targeting the PI3K-AKT. RESULTS: In this study, the target gene ITGA5 may be identified as a valuable prognostic marker for HNSCC. The results of enrichment analysis showed that ITGA5 was mainly involved in the dynamic process of extracellular matrix, which may affect the migration or metastasis of tumor cells. Meanwhile, ITGA5 may be closely related to the infiltration of M2 macrophages, and its secretory phenotypes TGFB1, PDGFA and PDGFB may affect the immunosuppressive phenotypes of tumor cells, which reflects the systemic influence of ITGA5 in HNSCC. In addition, the expression levels of ITGA5 were negatively correlated with the efficacy of targeting PI3K-AKT chemotherapy. CONCLUSION: ITGA5 can be used as a potential marker to systematically associate with prognosis of HNSCC, which may be associated with HNSCC malignant phenotype, immunosuppression and chemotherapy resistance.

MG53's non-physiologic interaction with insulin receptor: lack of effect on insulin-stimulated Akt phosphorylation in muscle, heart and liver tissues.

Rationale: MG53's known function in facilitating tissue repair and anti-inflammation has broad applications to regenerative medicine. There is controversy regarding MG53's role in the development of type 2 diabetes mellitus. Objective: This study aims to address this controversy - whether MG53's myokine function contributes to inhibition of insulin signaling in muscle, heart, and liver tissues. Study design: We determined the binding affinity of the recombinant human MG53 (rhMG53) to the insulin receptor extracellular domain (IR-ECD) and found low affinity of interaction with Kd (>480 nM). Using cultured C2C12 myotubes and HepG2 cells, we found no effect of rhMG53 on insulin-stimulated Akt phosphorylation (p-Akt). We performed in vivo assay with C57BL/6J mice subjected to insulin stimulation (1 U/kg, intraperitoneal injection) and observed no effect of rhMG53 on insulin-stimulated p-Akt in muscle, heart and liver tissues. Conclusion: Overall, our data suggest that rhMG53 can bind to the IR-ECD, however has a low likelihood of a physiologic role, as the Kd for binding is ~10,000 higher than the physiologic level of MG53 present in the serum of rodents and humans (~10 pM). Our findings question the notion proposed by Xiao and colleagues - whether targeting circulating MG53 opens a new therapeutic avenue for type 2 diabetes mellitus and its complications.

SPP1 induces idiopathic pulmonary fibrosis and NSCLC progression via the PI3K/Akt/mTOR pathway.

BACKGROUND: The prevalence of non-small cell lung cancer (NSCLC) is notably elevated in individuals diagnosed with idiopathic pulmonary fibrosis (IPF). Secreted phosphoprotein 1 (SPP1), known for its involvement in diverse physiological processes, including oncogenesis and organ fibrosis, has an ambiguous role at the intersection of IPF and NSCLC. Our study sought to elucidate the function of SPP1 within the pathogenesis of IPF and its subsequent impact on NSCLC progression. METHODS: Four GEO datasets was analyzed for common differential genes and TCGA database was used to analyze the prognosis. The immune infiltration was analyzed by TIMER database. SPP1 expression was examined in human lung tissues, the IPF fibroblasts and the BLM-induced mouse lung fibrosis model. Combined with SPP1 gene gain- and loss-of-function, qRT-PCR, Western blot, EdU and CCK-8 experiments were performed to evaluate the effects and mechanisms of SPP1 in IPF progression. Effect of SPP1 on NSCLC was detected by co-cultured IPF fibroblasts and NSCLC cells. RESULTS: Through bioinformatics analysis, we observed a significant overexpression of SPP1 in both IPF and NSCLC patient datasets, correlating with enhanced immune infiltration of cancer-associated fibroblasts in NSCLC. Elevated levels of SPP1 were detected in lung tissue samples from IPF patients and bleomycin-induced mouse models, with partial colocalization observed with α-smooth muscle actin. Knockdown of SPP1 inhibits TGF-ß1-induced differentiation of fibroblasts to myofibroblasts and the proliferation of IPF fibroblasts. Conversely, SPP1 overexpression promoted IPF fibroblast proliferation via PI3K/Akt/mTOR pathway. Furthermore, IPF fibroblasts promoted NSCLC cell proliferation and activated the PI3K/Akt/mTOR pathway; these effects were attenuated by SPP1 knockdown in IPF fibroblasts. CONCLUSIONS: Our findings suggest that SPP1 functions as a molecule promoting both fibrosis and tumorigenesis, positioning it as a prospective therapeutic target for managing the co-occurrence of IPF and NSCLC.

Cold Exposure Alleviates T2DM Through Plasma-Derived Extracellular Vesicles.

Purpose: Anecdotal reports have praised the benefits of cold exposure, exemplified by activities like winter swimming and cold water immersion. Cold exposure has garnered acclaim for its potential to confer benefits and potentially alleviate diabetes. We posited that systemic cold temperature (CT, 4-8°C) likely influences the organism's blood components through ambient temperature, prompting our investigation into the effects of chronic cold exposure on type 2 diabetic (T2DM) mice and our initial exploration of how cold exposure mitigates the incidence of T2DM. Methods: The effects of CT (4-8°C) or room temperature (RT, 22-25°C) on T2DM mice were investigated. Mice blood and organ specimens were collected for fully automated biochemical testing, ELISA, HE staining, immunohistochemistry, and immunofluorescence. Glucose uptake was assessed using flow cytometry with 2-NBDG. Changes in potential signaling pathways such as protein kinase B (AKT), phosphorylated AKT (p-AKT), insulin receptor substrates 1 (IRS1), and phosphorylated IRS1 (p-IRS1) were evaluated by Western blot. Results: CT or CT mice plasma-derived extracellular vesicles (CT-EVs) remarkably reduced blood glucose levels and improved insulin sensitivity in T2DM mice. This treatment enhanced glucose metabolism, systemic insulin sensitivity, and insulin secretion function while promoting glycogen accumulation in the liver and muscle. Additionally, CT-EVs treatment protected against the streptozocin (STZ)-induced destruction of islets in T2DM mice by inhibiting ß-cell apoptosis. CT-EVs also shielded islets from destruction and increased the expression of p-IRS1 and p-AKT in adipocytes and hepatocytes. In vitro experiments further confirmed its pro-insulin sensitivity effect. Conclusion: Our data indicate that cold exposure may have a potentially beneficial effect on the development of T2DM, mainly through the anti-diabetic effect of plasma-derived EVs released during cold stimulation. This phenomenon could significantly contribute to understanding the lower prevalence of diabetes in colder regions.

mTORC2 inhibition by JR-AB2-011 improves IL-1ß-induced inflammation, catabolic response, and apoptosis in human chondrocytes through IκB-α/NF-κB p65.

Osteoarthritis (OA) is a very common chronic joint condition marked by inflammation and cartilage loss. mTOR is a well-known mediator of inflammation, cell survival, and aging; however, its role in OA has not been determined. To explore the role of mTORC2 in OA-and associated pathological changes, we examined the contribution of mTORC2-mediated Akt, rictor and IκB-α/NF-κB p65 pathway in interleukin (IL)-1ß-treated human chondrocytes. We focused on the protein expression of proinflammatory cytokines and catabolic and apoptotic factors, including TNF-α, IL-6, iNOS, MMP13, Bax, and caspase3, which may occur through this signalling pathway in IL-1ß-treated chondrocytes. Chondrocytes were cultured and treated with either 2 ng/mL IL­1ß alone or in combination with increasing concentrations of JR-AB2-011 (50, 100, or 250 µM), a selective mTORC2 inhibitor. The protein levels of phosphorylated (p)­Akt, Akt, rictor, p-NF-κB p65, NF-κB p65, IκB-α, p-IκB-α, iNOS, MMP13, Bax, and caspase3 were evaluated by Western blotting. In IL-1ß-stimulated chondrocytes, mTORC2 activity was increased with increased phosphorylation of Akt and expression of rictor. IL-1ß increased the expression of p-IκBα, p-NF-κB p65, NF-κB p65, IL-6, TNF-α, iNOS, Bax, and caspase3 proteins and decreased the expression of IκB-α. All of these IL-1ß-induced alterations were prevented by JR-AB2-011. The main novel finding in the present study is that selective mTORC2 inhibition by JR-AB2-011 prevents the inflammatory, catabolic, and apoptotic responses induced by IL-1ß via modulation of IκB-α/NF-κB activity. Therefore, we demonstrated a previously unknown function of mTORC2 inhibition that seems to be a potential therapeutic target for OA.

A novel role for WZ3146 in the inhibition of cell proliferation via ERK and AKT pathway in the rare EGFR G719X mutant cells.

Mutations in the epidermal growth factor receptor (EGFR) gene are common driver oncogenes in non-small cell lung cancer (NSCLC). Studies have shown that afatinib is beneficial for NSCLC patients with rare EGFR mutations. However, the effectiveness of tyrosine kinase inhibitors (TKIs) against the G719X (G719A, G719C and G719S) mutation has not been fully established. Herein, using the CRISPR method, the EGFR G719X mutant cell lines were constructed to assess the sensitivity of the rare mutation G719X in NSCLC. WZ3146, a novel mutation-selective EGFR inhibitor, was conducted transcriptome sequencing and in vitro experiments. The results showed that WZ3146 induced cytotoxic effects, inhibited growth vitality and proliferation via ERK and AKT pathway in the EGFR G719X mutant cells. Our findings suggest that WZ3146 may be a promising treatment option for NSCLC patients with the EGFR exon 18 substitution mutation G719X.

Integrin αVß3 mediates porcine deltacoronavirus infection and inflammatory response through activation of the FAK-PI3K-AKT-nf-κB signalling pathway.

Porcine deltacoronavirus (PDCoV) is an emerging porcine enteropathogenic coronavirus that causes acute watery diarrhoea in piglets, resulting in significant economic losses to the global swine industry. However, the underlying mechanism of PDCoV infection is not well defined, which seriously hinders the development of effective drugs and vaccines. Integrins (ITG) are heterodimeric transmembrane glycoproteins that play important roles in the life cycle of many viruses. In the current study, the viral entry pathways of PDCoV were explored and the role of ITGαVß3 was investigated during PDCoV infection. Our results showed that the lysosomal acidification inhibitor bafilomycin-A1 (Baf-A1) significantly reduced PDCoV infection, while exogenous protease facilitated PDCoV infection and even allowed PDCoV entry to bypass the endosomal pathway, suggesting PDCoV entry into cells via the endocytic pathway and the exogenous protease-mediated pathway simultaneously. Furthermore, ITGαVß3 was identified to be involved in PDCoV infection, especially during viral entry stages. PDCoV infection triggers the activation of the focal adhesion kinase (FAK)-phosphatidylinositol 3-kinase (PI3K)-serine/threonine-specific protein kinase (AKT) signalling pathway, and this activation is ITGαVß3-dependent, suggesting that the activation of the FAK-PI3K-AKT signalling pathway during PDCoV infection is mediated by ITGαVß3. Our results further demonstrated that PDCoV infection induced the expression of inflammatory cytokines, which was mediated by activation of the ITGαVß3-FAK-PI3K-AKT-nuclear transcription factor-κB (NF-κB) signalling pathway. Overall, the results revealed that ITGαVß3 is an essential host factor for PDCoV infection and can serve as a supplementary receptor to facilitate PDCoV infection, which can help us to explore the molecular mechanism of PDCoV infection.

Identifying the host factors required for entry will be helpful in uncovering the pathogenesis mechanisms and developing antivirals against the emerging coronavirus porcine deltacoronavirus (PDCoV). Herein, we revealed that PDCoV enters cells via the endocytic and exogenous protease-mediated pathways simultaneously. Integrins (ITG) αVß3 is a host factor required for PDCoV infection, especially during virus adhesion, invasion, and release. Most importantly, PDCoV promotes viral infection by activating the ITGαVß3-focal adhesion kinase (FAK)-phosphatidylinositol 3-kinase (PI3K)-serine/threonine-specific protein kinase (AKT) signalling pathway and induces inflammation by activating the ITGαVß3-FAK-PI3K-AKT-NF-κB signalling pathway. Overall, this is the first study to identify ITGαVß3 as an essential factor for PDCoV infection, which can help us to confirm the molecular regulatory mechanism and provide a comprehensive resource for PDCoV infection.

MUC1­ND interacts with TRPV1 to promote corneal epithelial cell proliferation in diabetic dry eye mice by partly activating the AKT signaling pathway.

Although both mucin1 (MUC1) and transient receptor potential cation channel subfamily V member 1 (TRPV1) have been reported to be associated with dry eye (DE) disease, whether they interact and their regulatory roles in diabetic DE disease are unknown. Diabetic DE model mice were generated by streptozotocin induction and assessed by corneal fluorescein staining, tear ferning (TF) tests, phenol red thread tests, hematoxylin and eosin staining of corneal sections and periodic acid Schiff staining of conjunctival sections. Cell proliferation was measured by CCK8 assay. Western blotting was performed to measure protein expression. Primary mouse corneal epithelial cells (MCECs) were cultured after enzymatic digestion. Immunofluorescence staining of MCECs and frozen corneal sections was conducted to assess protein expression and colocalization. Coimmunoprecipitation was performed to detect protein­protein interactions. It was found that, compared with control mice, diabetic DE mice exhibited increased corneal epithelial defects, reduced tear production, poorer TF pattern grades and impaired corneal and conjunctival tissues. In vivo and in vitro experiments showed that hyperglycemia impaired cell proliferation, accompanied by decreased levels of the MUC1 extracellular domain (MUC1­ND) and TRPV1. Additionally, it was found that capsazepine (a TRPV1 antagonist) inhibited the proliferation of MCECs. Notably, MUC1­ND was shown to interact with the TRPV1 protein in the control group but not in the diabetic DE group. It was also found that the AKT signaling pathway was attenuated in the diabetic DE mice and downstream of TRPV1. MUC1­ND interacted with TRPV1, partly activating the AKT signaling pathway to promote MCEC proliferation. The present study found that the interaction of MUC1­ND with TRPV1 promotes MCEC proliferation by partly activating the AKT signaling pathway, providing new insight into the pathogenesis of corneal epithelial dysfunction in diabetic DE disease.