INTRODUCTION:Paclitaxel is a microtubule-stabilizing drug used to treat several types of cancer, including ovarian and breast cancer. Because of its antiproliferative effect on vascular smooth muscle cells, balloons and stents are coated with paclitaxel for use in coronary revascularization and prevention of in-stent restenosis (ISR). However, mechanisms underlying ISR are complicated. Platelet activation is one of the major causes of ISR after percutaneous coronary intervention. Although the antiplatelet activity of paclitaxel was noted in rabbit platelets, the effect of paclitaxel on platelets remains unclear. This study investigated whether paclitaxel exhibits antiplatelet activity in human platelets.METHODS AND RESULTS:Paclitaxel inhibited platelet aggregation induced by collagen but not that induced by thrombin, arachidonic acid, or U46619, suggesting that paclitaxel is more sensitive to the inhibition of collagen-induced platelet activation. Moreover, paclitaxel blocked collagen receptor glycoprotein (GP) VI downstream signaling molecules, including Lyn, Fyn, PLCγ2, PKC, Akt, and MAPKs. However, paclitaxel did not directly bind to GPVI and cause GPVI shedding, as detected by surface plasmon resonance and flow cytometry, respectively, indicating that paclitaxel may interfere with GPVI downstream signaling molecules, such as Lyn and Fyn. Paclitaxel also prevented granule release and GPIIbIIIa activation induced by collagen and low convulxin doses. Moreover, paclitaxel attenuated pulmonary thrombosis and delayed platelet thrombus formation in mesenteric microvessels without significantly affecting hemostasis.CONCLUSION:Paclitaxel exerts antiplatelet and antithrombotic effects. Thus, paclitaxel may provide additional benefits beyond its antiproliferative effect when used in drug-coated balloons and drug-eluting stents for coronary revascularization and prevention of ISR.
Figure S1. Inclusion Flowchart. Figure S2. Diagram of the image processing. Figure S3. Profiles of the Radiomic Features.
Trauma-hemorrhagic shock (THS) is a medical emergency that is encountered by physicians in the emergency department. Chuan Xiong is a traditional Chinese medicine and ligustrazine is a natural compound from it. Ligustrazine improves coronary blood flow and reduces cardiac ischemia in animals through Ca2+ and ATP-dependent vascular relaxation. It also decreases the platelets' bioactivity and reduces reactive oxygen species formation. We hypothesized that ligustrazine could protect liver by decreasing the inflammation response, protein production, and apoptosis in THS rats. Ligustrazine at doses of 100 and 1000 μg/mL was administrated in Kupffer cells isolated from THS rats. The protein expressions were detected via western blot. The THS showed increased inflammation response proteins, mitochondria-dependent apoptosis proteins, and had a compensation effect on the Akt pathway. After ligustrazine treatment, the hemorrhagic shock Kupffer cells decreased inflammatory response and mitochondria-dependent apoptosis and promoted a more compensative effect of the Akt pathway. It suggests ligustrazine reduces inflammation response and mitochondria-dependent apoptosis induced by THS in liver Kupffer cells and promotes more survival effects by elevating the Akt pathway. These findings demonstrate the beneficial effects of ligustrazine against THS-induced hepatic injury, and ligustrazine could be a potential medication to treat the liver injury caused by THS.
Oxidative stress-induced brain cell damage is a crucial factor in the pathogenesis of reactive oxygen species (ROS)-associated neurological diseases. Further, studies show that astrocytes are an important immunocompetent cell in the brain and play a potentially significant role in various neurological diseases. Therefore, elimination of ROS overproduction might be a potential strategy for preventing and treating neurological diseases. Accumulating evidence indicates that calycosin, a main active ingredient in the Chinese herbal medicine Huangqi (Radix Astragali Mongolici), is a potential therapeutic candidate with anti-inflammation and/or anticancer effects. Here, we investigated the protective effect of calycosin in brain astrocytes by mimicking in vitro oxidative stress using H2 O2 . The results revealed that H2 O2 significantly induced ROS and inflammatory factor (tumor necrosis factor [TNF]-α and interleukin [IL]-1β) production, whereas post-treatment with calycosin dramatically and concentration-dependently suppressed H2 O2 -induced damage by enhancing cell viability, repressing ROS and inflammatory factor production, and increasing superoxide dismutase (SOD) expression. Additionally, we found that calycosin facilitated nuclear factor erythroid 2-related factor 2 (Nrf2) expression and promoted its nuclear translocation, thereby inducing the expression of antioxidant molecules (heme oxygenase [HO]-1 and SOD) following H2 O2 treatment. Moreover, calycosin did not attenuated H2 O2 -induced astrocyte damage and ROS production in the presence of the ML385 (a Nrf2-specific inhibitor) and following Nrf2 silencing. Furthermore, calycosin failed to increase Akt phosphorylation and mitigate H2 O2 -induced astrocyte damage in the presence of the LY294002 (a selective phosphatidylinositol 3-kinase inhibitor), indicating that calycosin-mediated regulation of oxidative-stress homeostasis involved Akt/Nrf2/HO-1 signaling. These findings demonstrated that calycosin protects against oxidative injury in brain astrocytes by regulating oxidative stress through the AKT/Nrf2/HO-1 signaling pathway.
Early and accurate prediction of endotracheal tube (ETT) location is pivotal for critically ill patients. Automatic and timely detection of faulty ETT locations from chest X-ray images may avert patients’ morbidity and mortality. Therefore, we designed convolutional neural network (CNN)-based algorithms to evaluate ETT position appropriateness relative to four detected key points, including tracheal tube end, carina, and left/right clavicular heads on chest radiographs. We estimated distances from the tube end to tracheal carina and the midpoint of clavicular heads. A DenseNet121 encoder transformed images into embedding features, and a CNN-based decoder generated the probability distributions. Based on four sets of tube-to-carina distance-dependent parameters (i.e., (i) 30–70 mm, (ii) 30–60 mm, (iii) 20–60 mm, and (iv) 20–55 mm), corresponding models were generated, and their accuracy was evaluated through the predicted L1 distance to ground-truth coordinates. Based on tube-to-carina and tube-to-clavicle distances, the highest sensitivity, and specificity of 92.85% and 84.62% respectively, were revealed for 20–55 mm. This implies that tube-to-carina distance between 20 and 55 mm is optimal for an AI-based key point appropriateness detection system and is empirically comparable to physicians’ consensus.
Platelets play a crucial role on hemostasis and are also involved in cardiovascular diseases, such as heart attack and stroke. Artesunate has been reported to possess multiple biological activities, including antitumor and anti-inflammatory activities. However, its effect on platelet activation remains unclear. Thus, we explored the detailed mechanisms underlying its antiplatelet effect. For the in vitro study, the data indicated that artesunate inhibited platelet aggregation induced by collagen, but not thrombin or U46619, indicating that artesunate may selectively inhibit collagen-mediated platelet activation Artesunate also blocked glycoprotein VI (GPVI) downstream signaling, including Syk, PLCγ2, PKC, Akt, and MAPKs. Moreover, artesunate could compete with collagen for binding to collagen receptor and bind to human recombinant GPVI with a high affinity (KD = 44 nM), indicating that it may directly interfere with GPVI. Artesunate also reduced collagen-induced granule release, calcium mobilization, and GPIIbIIIa activation. For the in vivo study, artesunate markedly prevented pulmonary thrombosis and delayed platelet thrombus formation in mesenteric veins and arteries but had minimal effects on hemostasis. In conclusion, we for the first time demonstrated that artesunate acts as a GPVI antagonist and effectively prevents platelet activation and thrombus formation with minimal risk of bleeding, highlighting its therapeutic potential in cardiovascular diseases.
Ethnopharmacological relevance: Solanum nigrum, commonly known as Makoi or black shade has been traditionally used in Asian countries and other regions of world to treat liver disorders, diarrhoea, inflammatory conditions, chronic skin ailments (psoriasis and ringworm), fever, hydrophobia, painful periods, eye diseases, etc. It has been observed that S. nigrum contains substances, like steroidal saponins, total alkaloid, steroid alkaloid, and glycoprotein, which show anti-tumor activity. However; there is no scientific evidence of the efficacy of S. nigrum in the treatment of cardiac hypertrophy. Aim: To investigate the ability of S. nigrum to attenuate Angiotensin II -induced cardiac hypertrophy and improve cardiac function through the suppression of protein kinase PKC-zeta and Mel-18-IGF-IIR signaling leading to the restoration of HSF2 desumolyation. Materials and methods: Cardiomyoblast cells (H9c2) were challenged with 100 nM Angiotensin-II (AngII) for 24 h and were then treated with different concentration of S.nigrum or Calphostin C for 24 h. The hypertrophic effect in cardiomyoblast cells were determined by immunofluorescence staining and the modulations in hypertrophic protein marker along with Protein Kinase C-zeta, MEL18, HSF2, and Insulin like growth factor II (IGFIIR), markers were analyzed by western blotting. In vivo experiments were performed using 12 week old male Wistar Kyoto rats (WKY) and Spontaneously hypertensive rats (SHR) separated into five groups. [1]Control WKY, [2] WKY -100 mg/kg of S.nigrum treatment, [3] SHR, [4] SHR-100 mg/kg of S.nigrum treatment, [5] SHR-300 mg/kg of S.nigrum treatment. S. nigrum was administered intraperitoneally for 8 week time interval. Results: Western blotting results indicate that S. nigrum significantly attenuates AngII induced cardiac hypertrophy. Furthermore, actin staining confirmed the ability of S. nigrum to ameliorate AngII induced cardiac hypertrophy. Moreover, S. nigrum administration suppressed the hypertrophic signaling mediators like Protein Kinase C-C, Mel-18, and IGFIIR in a dose-dependent manner and HSF2 activation (restore deSUMOlyation) that leads to downregulation of IGF-IIR expression. Additionally in vivo experiments demonstrate the reduced heart sizes of S. nigrum treated SHRs rats when compared to control WKY rats. Conclusion: Collectively, the data reveals the cardioprotective effect of S. nigrum inhibiting PKC-C with alleviated IGF IIR level in the heart that profoundly remits cardiac hypertrophy for hypertension-induced heart failure.
Urothelial bladder cancer is rapidly spreading across Western countries, and therapy has shown little-to-moderate effects on bladder cancer. Thus, focusing on curbing cancer incidence has become crucial. The aim of the present study was to investigate the anticancer effects of Tannic acid (TA) in human bladder cancer. UMUC3 bladder cancer cells were treated with different concentrations of TA (0–100 µM) and tested for cell viability, colony formation, and apoptosis. The involvement of the phosphoinositide-3 kinase (PI3K)/Akt pathway in the action of TA was examined. TA treatment significantly inhibited the viability and increased percentage of apoptotic cells, thereby decreasing antiapoptotic proteins (BCL2, MCL-1, and BCL-XL) expression, resulting in the Caspase-3 activation. TA treatment decreased stem cell markers expression such as SOX2, OCT4, and NANOG. Additionally, TA treatment significantly reduced the phosphorylation levels of Akt in bladder cancer cells. Our study demonstrates the growth inhibitory effects of TA in bladder cancer cells, and highlights its potential as an anticancer agent for bladder cancer.
Lung cancer is the major cause of cancer associated mortality. Mutations in EGFR have been implicated in lung cancer pathogenesis. Gefitinib (GF) is a RTKI (receptor tyrosine kinase inhibitor) first-choice drug for EGFR mutated advanced lung cancer. However, drug toxicity and cancer cell resistance lead to treatment failure. Consequently, new therapeutic strategies are urgently required. Therefore, this study was aimed at identifying tumor suppressive compounds that can synergistically improve Gefitinib chemosensitivity in the lung cancer treatment. Medicinal plants offer a vast platform for the development of novel anticancer agents. Daidzein (DZ) is an isoflavone compound extracted from soy plants and has been shown to possess many medicinal benefits. The anticancer potential of GF and DZ combination treatment was investigated using MTT, western blot, fluorescent microscopy imaging, flow cytometry and nude mice tumor xenograft techniques. Our results demonstrate that DZ synergistically induces c-Jun nuclear translocation through ROS/ASK1/JNK and downregulates EGFR-STAT/AKT/ERK pathways to activate apoptosis and a G0/G1 phase cell cycle blockade. In in-vivo, the combination treatment significantly suppressed A549 lung cancer cells tumor xenograft growth without noticeable toxicity. Daidzein supplements with current chemotherapeutic agents may well be an alternative strategy to improve the treatment efficacy of lung adenocarcinoma.
Background:Hypertension is a severe public health risk factor worldwide. Elevated angiotensin II (Ang II) produced by the renin-angiotensin-aldosterone system can lead to hypertension and its complications.Method:In this study, we addressed the cardiac-injury effects of Ang II and investigated the signaling mechanism induced by Ang II. Both H9c2 cardiomyoblast cells and neonatal rat cardiomyocytes were exposed to Ang II to observe hypertension-related cardiac apoptosis.Results:The results of western blotting revealed that Ang II significantly attenuated the IGF1R-PI3K-AKT pathway via the Ang II-AT1 receptor axis and phosphatase and tensin homolog expression. Furthermore, real-time PCR showed that Ang II also activated miR-320-3p transcription to repress the PI3K-Akt pathway. In the heart tissue of spontaneously hypertensive rats, activation of the IGF1R survival pathway was also reduced compared with that in Wistar-Kyoto rats, especially in aged spontaneously hypertensive rats.Conclusion:Hence, we speculate that the Ang II-AT1 receptor axis induces both phosphatase and tensin homolog and miR-320-3p expression to downregulate the IGF1R-PI3K-AKT survival pathway and cause cell apoptosis in the heart.
Exposure to air pollutants may elevate the injury severity scores (ISSs) for road traffic injuries (RTIs). This multicenter cross-sectional study aimed to investigate the associations between air pollution, weather conditions, and RTI severity. This retrospective study was performed in Taiwan in 2018. The location of each road traffic accident (RTA) was used to determine the nearest air quality monitoring and weather station, and the time of each RTA was matched to the corresponding hourly air pollutant concentration and weather factors. Five multiple logistic regression models were used to compute the risk of sustaining severe injury (ISS ≥ 9). Of the 14,973 patients with RTIs, 2853 sustained severe injury. Moderate or unhealthy air quality index, higher exposure to particulate matter ≤2.5 μm in diameter, bicyclists or pedestrians, greater road width, nighttime, and higher temperature and relative humidity were significant risk factors for severe injury. Exposure to nitrogen oxide and ozone did not increase the risk. Auto occupants and scene-to-hospital time were the protective factors. Sensitivity analyses showed consistent results between air pollutants and the risk of severe injury. Poor air quality and hot and humid weather conditions were associated with severe RTIs. Active commuters were at higher risk of sustaining severe RTI.
Hypertension is a common chronic cardiovascular disease reported among both men and women. Hypertension in males affects the testis and reproduction function; however, the pathogenesis is poorly understood. Rapamycin has been reported to have a variety of beneficial pharmacological effects; however, high-doses rapamycin does have side effects such as immunosuppression. The present study investigates whether low-dose rapamycin can reduce the damage caused by hypertension to the testis of spontaneously hypertensive rats (SHRs) and further examines molecular mechanism of low-dose rapamycin in preventing testicular toxicity induced by angiotensin II (Ang II). Low rapamycin dose restores the testicle size, histological alterations, 3β-hydroxysteroid dehydrogenase (3β-HSD) expression, and prevents apoptosis in SHR rats. Ang II downregulates angiotensin-converting enzyme-2 (ACE2) expression through AT1R, p-ERK, and MAS receptor in LC-540 Leydig cells in a dose-dependent manner. Low doses of rapamycin effectively upregulate steroidogenic enzymes, steroidogenic acute regulatory protein and 3β-HSD expression in Leydig cells. Rapamycin upregulates ACE2 expression through p-PKAc and p-PI3k in Ang II-treated cells. Further, rapamycin curbs mitochondrial superoxide generation and depleted mitochondrial membrane potential induced by Ang II through activation of Nrf2-mediated Gpx4 and superoxide dismutase 2 expression. Our results revealed the involvement of ACE2, AT1R, AT2R, PKAc, and oxidative stress in Ang-II-induced testicular toxicity, suggesting low-dose rapamycin could be a potential therapeutic candidate to attenuate testicular toxicity.
Some clinical studies have indicated the patients with Alzheimer's disease (AD) display an increased risk of cardiovascular disease (CVD). Here, to examine the relationship between AD and CVDs, we investigated the changes in heart function in triple-transgenic late-stage AD model mice (3× Tg-AD; APPSwe, PS1M146V, and tauP301L). We fed the AD mice folic acid (FA) or folinic acid (FN) and analyzed the protective effects of the compounds on the heart; specifically, 20-month-old triple-transgenic AD mice, weighing 34-55 g, were randomly allocated into three groups-the AD, AD + FA, and AD + FN groups-and subject to gastric feeding with FA or FN once daily at 12 mg/kg body weight (BW) for 3 months. Mouse BWs were assessed throughout the trial, at the end of which the animals were sacrificed using carbon dioxide suffocation. We found that BW, whole-heart weight, and left-ventricle weight were reduced in the AD + FA and AD + FN groups as compared with the measurements in the AD group. Furthermore, western blotting of excised heart tissue revealed that the levels of the hypertrophy-related protein markers phospho(p)-p38 and p-c-Jun were markedly decreased in the AD + FA group, whereas p-GATA4, and ANP were strongly reduced in the AD + FN group. Moreover, the fibrosis-related proteins uPA, MMP-2, MEK1/2 and SP-1 were decreased in the heart in both AD + FN group. In summary, our results indicate that FA and FN can exert anti-cardiac hypertrophy and fibrosis effects to protect the heart in aged triple-transgenic AD model mice, particular in FN.
Habitual chewing of the areca nut increases the risk of mortality owing to cardiovascular disease, but few reports have revealed the cardiotoxicity mechanism of the areca nut. Arecoline has been reported to be the primary toxic constituent in the areca nut. In order to study the acute cardiotoxicity of the areca nut in the development of pathologic heart hypertrophy, we induced heart injury in rats using arecoline. Arecoline at a low dosage (5 mg/kg/day) or a high dosage (50 mg/kg/day) was intraperitoneally injected to Sprague-Dawley rats for 21 days. The change of heart function and biochemical pathways were investigated with echocardiography and Western blot. The results were presented that heart functions were weakened by arecoline stimulation, and western blotting analysis revealed an elevation in BNP levels in the heart after arecoline exposure. Arecoline induced IL-6-mediated activation of the MEK5/ERK5 and JAK2/STAT3 pathways, as well as mitogen-activated protein kinase signaling cascades. Further, arecoline increased the calcineurin and NFATc3 levels in the heart. In summary, our results suggest that arecoline causes significantly cardiotoxicity and heart damage by inducing several hypertrophy-related signaling pathways, including IL-6-induced MEK5/ERK5, JAK2/STAT3, mitogen-activated protein kinases, and calcineurin signaling pathways. The study elucidated, for the first time, the possible cardiac hypertrophy mechanisms underlying the cardiotoxicity of the areca nut.
Diabetic neuropathy is a common complication of diabetes mellitus, posing a challenge in treatment. Previous studies have indicated the protective role of mesenchymal stem cells against several disorders. Although they can repair nerve injury, their key limitation is that they reduce viability under stress conditions. We recently observed that overactivation of the carboxyl terminus of heat shock protein 70 (Hsp70) interacting protein (CHIP) considerably rescued cell viability under hyperglycemic stress and played an essential role in promoting the beneficial effects of Wharton's jelly-derived mesenchymal stem cells (WJMSCs). Thus, the present study was designed to unveil the protective effects of CHIP-overexpressing WJMSCs against neurodegeneration using in vivo animal model based study. In this study, western blotting observed that CHIP-overexpressing WJMSCs could rescue nerve damage observed in streptozotocin-induced diabetic rats by activating the AMPKα/AKT and PGC1α/SIRT1 signaling pathway. In contrast, these signaling pathways were downregulated upon silencing CHIP. Furthermore, CHIP-overexpressing WJMSCs inhibited inflammation induced in the brains of diabetic rats by suppressing the NF-κB, its downstream iNOS and cytokines signaling nexus and enhancing the antioxidant enzyme system. Moreover, TUNEL assay demonstrated that CHIP carrying WJMSCs suppressed the apoptotic cell death induced in STZ-induced diabetic group. Collectively, our findings suggests that CHIP-overexpressing WJMSCs might exerts beneficial effects, which may be considered as a therapeutic strategy against diabetic neuropathy complications.
Diabetic nephropathy is a serious chronic complication affecting at least 25% of diabetic patients. Hyperglycemia associated advanced glycation end-products (AGEs) increase tubular epithelial-myofibroblast transdifferentiation (TEMT) and extracellular matrix synthesis and thereby causes renal fibrosis. The chalcone isoliquiritigenin, found in many herbs of Glycyrrhiza family, is known for potential health-promoting effects. However, their effects on AGE-associated renal proximal tubular fibrosis are not known yet. In this study, the effect of isoliquiritigenin on AGE-induced renal proximal tubular fibrosis was determined in cultured HK-2 cell line. The results show that 200 μg/mL of AGE-induced TEMT and the formed myofibroblasts synthesized collagen to increase extracellular matrix formation thereby lead to renal tubular fibrosis. However, treatment with 200 nM of isoliquiritigenin considerably inhibited the TEMT and suppressed the TGFβ/STAT3 mechanism to inhibit collagen secretion. Therefore, isoliquiritigenin effectively suppressed AGE-induced renal tubular fibrosis.
The insulin-like growth factor II receptor (IGF-IIR) induces myocardial hypertrophy under various pathological conditions like diabetes and hypertension via G protein receptors like Gαq or Gαs. Increased expression of the ligand IGF II and IGF-IIR induces pathological hypertrophy through downstream signaling mediators such as calcineurin, nuclear factor of activated T cells 3 and calcium-calmodulin (CaM)-dependent kinase II (CaMKII)-histone deacetylase 4 (HDAC4). The dried stigma of Crocus sativus L. (saffron) has a long repute as a traditional medicine against various disorders. In the present study, we have investigated whether C. sativus extract (CSE) canameliorate Leu27 IGF-II triggered hypertrophy and have elucidated the underlying mechanism of protection. Additionally, the effects of oleic acid (OA), an activator of calcineurin and CaMKII was investigated thereof. The results demonstrate that CSE can ameliorate Leu27 IGF-II-induced hypertrophy seemingly through regulation of calcineurin-NFAT3 and CaMKII-HDAC4 signaling cascade.
BACKGROUND More than 79.2 million confirmed COVID-19 cases and 1.7 million deaths were caused by SARS-CoV-2; the disease was named COVID-19 by the World Health Organization. Control of the COVID-19 epidemic has become a crucial issue around the globe, but there are limited studies that investigate the global trend of the COVID-19 pandemic together with each country’s policy measures. OBJECTIVE We aimed to develop an online artificial intelligence (AI) system to analyze the dynamic trend of the COVID-19 pandemic, facilitate forecasting and predictive modeling, and produce a heat map visualization of policy measures in 171 countries. METHODS The COVID-19 Pandemic AI System (CPAIS) integrated two data sets: the data set from the Oxford COVID-19 Government Response Tracker from the Blavatnik School of Government, which is maintained by the University of Oxford, and the data set from the COVID-19 Data Repository, which was established by the Johns Hopkins University Center for Systems Science and Engineering. This study utilized four statistical and deep learning techniques for forecasting: autoregressive integrated moving average (ARIMA), feedforward neural network (FNN), multilayer perceptron (MLP) neural network, and long short-term memory (LSTM). With regard to 1-year records (ie, whole time series data), records from the last 14 days served as the validation set to evaluate the performance of the forecast, whereas earlier records served as the training set. RESULTS A total of 171 countries that featured in both databases were included in the online system. The CPAIS was developed to explore variations, trends, and forecasts related to the COVID-19 pandemic across several counties. For instance, the number of confirmed monthly cases in the United States reached a local peak in July 2020 and another peak of 6,368,591 in December 2020. A dynamic heat map with policy measures depicts changes in COVID-19 measures for each country. A total of 19 measures were embedded within the three sections presented on the website, and only 4 of the 19 measures were continuous measures related to financial support or investment. Deep learning models were used to enable COVID-19 forecasting; the performances of ARIMA, FNN, and the MLP neural network were not stable because their forecast accuracy was only better than LSTM for a few countries. LSTM demonstrated the best forecast accuracy for Canada, as the root mean square error (RMSE), mean absolute error (MAE), and mean absolute percentage error (MAPE) were 2272.551, 1501.248, and 0.2723075, respectively. ARIMA (RMSE=317.53169; MAPE=0.4641688) and FNN (RMSE=181.29894; MAPE=0.2708482) demonstrated better performance for South Korea. CONCLUSIONS The CPAIS collects and summarizes information about the COVID-19 pandemic and offers data visualization and deep learning–based prediction. It might be a useful reference for predicting a serious outbreak or epidemic. Moreover, the system undergoes daily updates and includes the latest information on vaccination, which may change the dynamics of the pandemic.
Background Recent studies indicate that umbilical cord stem cells are cytoprotective against several disorders. One critical limitation in using stem cells is reduction in their viability under stressful conditions, such as diabetes. However, the molecular intricacies responsible for diabetic conditions are not fully elucidated. Methods Effects of HG on Wharton's jelly derived mesenchymal stem cells (WJMSCs) viability was evaluated by MTT assay and flow cytometry. The mechanism responsible for HG-induced PTEN degradation was assessed using loss and gain of function, immunofluorescence, co-immunoprecipitation, and western blot analysis. Co-culturing of CHIP-overexpressed WJMSCs with embryo derived cardiomyoblasts was performed to analyze their ameliorative effects. The therapeutic effects of CHIP expressing WJMSCs were further validated in Sprague Dawley male (eight weeks old) STZ-induced diabetic animals by echocardiography, immunohistochemistry, hematoxylin eosin, and masson’s trichrome and TUNEL staining. Multiple comparisons were accessed through one‐way ANOVA and p -Value of <0.05 was considered statistically significant. Results In this study, we found that high glucose (HG) conditions induced loss of chaperone homeostasis, stabilized PTEN, triggered the downstream signaling cascade, and induced apoptosis and oxidative stress in Wharton's jelly derived mesenchymal stem cells (WJMSCs). Increased CHIP expression promoted PTEN degradation via the ubiquitin-proteasome system and shortened its half-life during HG stress. Docking studies confirmed the interaction of CHIP with PTEN and FOXO3a with the Bim promoter region. Further, it was found that the chaperone system is involved in CHIP-mediated PTEN proteasomal degradation. CHIP depletion stabilizes PTEN whereas PTEN inhibition showed an inverse effect. CHIP overactivation suppressed the binding of FOXO3a with bim . Co-culturing CHIP overexpressed WJMSCs suppressed HG-induced apoptosis and oxidative stress in cardiac cells. Finally, CHIP overexpression and PTEN inhibition minimized blood glucose levels, improved body and heart weight, and rescued hyperglycemia-induced cardiac injury in diabetic rats. Conclusion The current study suggests that CHIP confers resistance to apoptosis and oxidative stress and modulates PTEN and the downstream signaling cascade by promoting PTEN proteasomal degradation, thereby potentially exerting therapeutic effects against diabetes-induced cardiomyopathies.
Basal macroautophagy/autophagy has recently been found in anucleate platelets. Platelet autophagy is involved in platelet activation and thrombus formation. However, the mechanism underlying autophagy in anucleate platelets require further clarification. Our data revealed that LC3-II formation and SQSTM1/p62 degradation were noted in H2O2-activated human platelets, which could be blocked by 3-methyladenine and bafilomycin A1, indicating that platelet activation may cause platelet autophagy. AMPK phosphorylation and MTOR dephosphorylation were also detected, and block of AMPK activity by the AMPK inhibitor dorsomorphin reversed SQSTM1 degradation and LC3-II formation. Moreover, autophagosome formation was observed through transmission electron microscopy and deconvolution microscopy. These findings suggest that platelet autophagy was induced partly through the AMPK-MTOR pathway. In addition, increased LC3-II expression occurred only in H2O2-treated Atg5f/f platelets, but not in H2O2-treated atg5−/− platelets, suggesting that platelet autophagy occurs during platelet activation. atg5−/− platelets also exhibited a lower aggregation in response to agonists, and platelet-specific atg5−/− mice exhibited delayed thrombus formation in mesenteric microvessles and decreased mortality rate due to pulmonary thrombosis. Notably, metabolic analysis revealed that sphingolipid metabolism is involved in platelet activation, as evidenced by observed several altered metabolites, which could be reversed by dorsomorphin. Therefore, platelet autophagy and platelet activation are positively correlated, partly through the interconnected network of sphingolipid metabolism. In conclusion, this study for the first time demonstrated that AMPK-MTOR signaling could regulate platelet autophagy. A novel linkage between AMPK-MTOR and sphingolipid metabolism in anucleate platelet autophagy was also identified: platelet autophagy and platelet activation are positively correlated.Abbreviations: 3-MA: 3-methyladenine; A.C.D.: citric acid/sod. citrate/glucose; ADP: adenosine diphosphate; AKT: AKT serine/threonine kinase; AMPK: AMP-activated protein kinase; ANOVA: analysis of variance; ATG: autophagy-related; B4GALT/LacCS: beta-1,4-galactosyltransferase; Baf-A1: bafilomycin A1; BECN1: beclin 1; BHT: butylate hydrooxytoluene; BSA: bovine serum albumin; DAG: diacylglycerol; ECL: enhanced chemiluminescence; EDTA: ethylenediamine tetraacetic acid; ELISA: enzyme-linked immunosorbent assay; GALC/GCDase: galactosylceramidase; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GBA/GluSDase: glucosylceramidase beta; GPI: glycosylphosphatidylinositol; H2O2: hydrogen peroxide; HMDB: human metabolome database; HRP: horseradish peroxidase; IF: immunofluorescence; IgG: immunoglobulin G; KEGG: Kyoto Encyclopedia of Genes and Genomes; LAMP1: lysosomal associated membrane protein 1; LC-MS/MS: liquid chromatography-tandem mass spectrometry; mAb: monoclonal antibody; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MPV: mean platelet volume; MTOR: mechanistic target of rapamycin kinase; ox-LDL: oxidized low-density lipoprotein; pAb: polyclonal antibody; PC: phosphatidylcholine; PCR: polymerase chain reaction; PI3K: phosphoinositide 3-kinase; PLS-DA: partial least-squares discriminant analysis; PRP: platelet-rich plasma; Q-TOF: quadrupole-time of flight; RBC: red blood cell; ROS: reactive oxygen species; RPS6KB/p70S6K: ribosomal protein S6 kinase B; SDS: sodium dodecyl sulfate; S.E.M.: standard error of the mean; SEM: scanning electron microscopy; SGMS: sphingomyelin synthase; SM: sphingomyelin; SMPD/SMase: sphingomyelin phosphodiesterase; SQSTM1/p62: sequestosome 1; TEM: transmission electron microscopy; UGT8/CGT: UDP glycosyltransferase 8; UGCG/GCS: UDP-glucose ceramide glucosyltransferase; ULK1: unc-51 like autophagy activating kinase 1; UPLC: ultra-performance liquid chromatography; PIK3C3/VPS34: phosphatidylinositol 3-kinase catalytic subunit type 3; PtdIns3P: phosphatidylinositol-3-phosphate; WBC: white blood cell; WT: wild type