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Background: Accurately stratifying patients with pulmonary arterial hypertension (PAH) is very important, and traditional risk scores still have internal heterogeneity. This study aimed to construct a risk stratification model that can accurately identify clinical worsening (CW) events in conventional low‐intermediate risk patients with pulmonary hypertension under targeted drug treatment by using echocardiographic parameters. Methods: This study is a single‐center, prospective study, including 105 PAH patients who underwent regular follow‐up at Guangdong Provincial People's Hospital from October 2021 to April 2023. The primary endpoint was the occurrence of CW, including death, hospitalization due to pulmonary hypertension, escalation of targeted drug therapy, and worsening of PAH. The predictive value of the echocardiography‐based three‐strata risk model was assessed using Kaplan‐Meier curves and COX regression analysis. Results: A total of 98 PAH patients were ultimately included in this study. The median follow‐up duration was 26 months (range 7–28 months). The echocardiography‐based three‐strata model included the ratio of tricuspid annular plane systolic excursion and pulmonary artery systolic pressure (TAPSE/PASP) and inferior vena cava (IVC). The echocardiography‐based three‐strata model had higher diagnostic value (C‐index =.76) compared to the 2022 ESC/ERS three‐strata model and four‐strata model (C‐index =.66 and C‐index =.61, respectively). PAH patients with lower TAPSE/PASP and wider IVC showed a higher CW rate compared to patients with higher TAPSE/PASP and normal IVC (HR = 15.1, 95%CI:4.4‐51.9, p <.001). Conclusion: The echocardiography‐based three‐strata model based on TAPSE/PASP and IVC can effectively improve the stratification of low‐intermediate risk PAH patients under targeted treatment. [ABSTRACT FROM AUTHOR]

Diabetic cardiomyopathy (DCM) is a chronic microvascular complication of diabetes that is generally defined as ventricular dysfunction occurring in patients with diabetes and unrelated to known causes. Several mechanisms have been proposed to contribute to the occurrence and persistence of DCM, in which oxidative stress and autophagy play a non‐negligible role. Diabetic cardiomyopathy is involved in a variety of physiological and pathological processes. The 5′ adenosine monophosphate‐activated protein kinase/nuclear factor‐erythroid 2‐related factor 2 (AMPK/Nrf2) are expressed in the heart, and studies have shown that asiaticoside (ASI) and activated AMPK/Nrf2 have a protective effect on the myocardium. However, the roles of ASI and AMPK/Nrf2 in DCM are unknown. The intraperitoneal injection of streptozotocin (STZ) and high‐fat feed were used to establish the DCM models in 100 C57/BL mice. Asiaticoside and inhibitors of AMPK/Nrf2 were used for intervention. Cardiac function, oxidative stress, and autophagy were measured in mice. DCM mice displayed increased levels of oxidative stress while autophagy levels declined. In addition, AMPK/Nrf2 was activated in DCM mice with ASI intervention. Further, we discovered that AMPK/Nrf2 inhibition blocked the protective effect of ASI by compound C and treatment with ML‐385. The present study demonstrates that ASI exerts a protective effect against DCM via the potential activation of the AMPK/Nrf2 pathway. Asiaticoside is a potential therapeutic target for DCM. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is the most frequent and aggressive malignant glioma. Due to patients' poor prognosis, it is of great clinical significance to determine new targets that may improve GBM treatment. In the present study, we showed that ubiquitin (Ub)‐conjugating enzyme E2T (UBE2T) was significantly overexpressed in GBM and could promote proliferation, invasion, and inhibit apoptosis of GBM cells. Mechanistically, UBE2T functioned as the Ub enzyme of ribosomal protein L6 (RPL6) and induced the ubiquitination and degradation of RPL6 in an E3 ligase‐independent manner through direct modification by K48‐linked polyubiquitination, thus contributing to the malignant progression of GBM cells. Furthermore, inhibiting the expression of RPL6 by UBE2T could not only reduce the expression of wild‐type p53, but also enhance the gain‐of‐function of mutant p53. Moreover, knockdown of UBE2T in LN229 cells obviously suppressed tumor growth in LN229 xenograft mouse models. Collectively, our study demonstrated that UBE2T promotes GBM malignancy through ubiquitination‐mediated degradation of RPL6 regardless of the p53 mutation status. It will provide new candidates for molecular biomarkers and therapeutic targets for clinical application in GBM. [ABSTRACT FROM AUTHOR]

Doxorubicin (Dox), an anthracycline antibiotic with potent antitumor effects, has limited clinical applications due to cumulative cardiotoxicity. Ca2+/calmodulin‐dependent protein kinase II (CaMKII) is implicated in the pathological progression of Dox‐induced cardiotoxicity. This study examined the hypothesis that CaMKII exacerbates Dox‐induced cardiotoxicity by promoting endoplasmic reticulum stress and apoptosis through regulation of the inositol‐requiring enzyme 1α (IRE1α)/spliced X‐box binding protein 1 (XBP1s) pathway. Our results demonstrated that CaMKII activation and IRE1α/XBP1s pathway were involved in Dox‐treated hearts. CaMKII inhibition with KN‐93 ameliorated Dox‐induced cardiac dysfunction and pathological myocardial changes. In addition, CaMKII inhibition prevented Dox‐induced endoplasmic reticulum stress and apoptosis. Moreover, CaMKII inhibition increased the expression of IRE1α and XBP1s in Dox‐treated hearts. The IRE1α inhibitor 4μ8C blocked the protective effect of CaMKII inhibition against Dox‐induced cardiotoxicity. Mechanistically, 4μ8C prevented the effects of CaMKII inhibition on Dox‐induced endoplasmic reticulum stress and apoptosis by inhibiting the expression of IRE1α and XBP1s. Additionally, treatment with rhADAMTS13 decreased the protein level of thrombospondin 1 (TSP1) and the phosphorylation of CaMKII in Dox‐treated human AC16 cardiomyocytes. Taken together, these results demonstrate that the ADAMTS13‐TSP1 axis regulates CaMKII activation and exacerbates Dox‐induced cardiotoxicity by triggering endoplasmic reticulum stress and apoptosis by inhibiting the IRE1α/XBP1s pathway. [ABSTRACT FROM AUTHOR]

This study was designed to investigate whether berbamine (BA)‐induced cardioprotective effects were related to 5′ adenosine monophosphate‐activated protein kinase (AMPK)/nuclear factor erythroid 2‐related factor (Nrf2) signaling and changes in the mitochondria in myocardial ischemia/reperfusion (I/R) injury. C57/BL6 mice were exposed to BA (10 mg/kg/d), with or without administration of the AMPK specific inhibitor compound C (5 mg/kg/d) or the Nrf2 specific inhibitor ML‐385 (30 mg/kg/d), and then subjected to a myocardial I/R operation. As expected, BA significantly improved post‐ischemic cardiac function, reduced infarct size and apoptotic cell death, decreased oxidative stress, and improved the mitochondrial state. Furthermore, BA markedly increased AMPK activation, Nrf2 nuclear translocation, and the levels of NAD(P)H quinone dehydrogenase and heme oxygenase‐1. Nevertheless, these BA‐induced changes were abrogated by compound C. In addition, ML‐385 also canceled the cardioprotective effects of BA but had little effect on AMPK activation. Our results demonstrate that BA alleviates myocardial I/R injury and the mitochondrial state by inhibiting apoptosis and oxidative stress via the AMPK/Nrf2 signaling pathway. [ABSTRACT FROM AUTHOR]

The isolation and subsequent molecular analysis of extracellular vesicles (EVs) derived from patient samples is a widely used strategy to understand vesicle biology and to facilitate biomarker discovery. Expressed prostatic secretions in urine are a tumor proximal fluid that has received significant attention as a source of potential prostate cancer (PCa) biomarkers for use in liquid biopsy protocols. Standard EV isolation methods like differential ultracentrifugation (dUC) co‐isolate protein contaminants that mask lower‐abundance proteins in typical mass spectrometry (MS) protocols. Further complicating the analysis of expressed prostatic secretions, uromodulin, also known as Tamm‐Horsfall protein (THP), is present at high concentrations in urine. THP can form polymers that entrap EVs during purification, reducing yield. Disruption of THP polymer networks with dithiothreitol (DTT) can release trapped EVs, but smaller THP fibres co‐isolate with EVs during subsequent ultracentrifugation. To resolve these challenges, we describe here a dUC method that incorporates THP polymer reduction and alkaline washing to improve EV isolation and deplete both THP and other common protein contaminants. When applied to human expressed prostatic secretions in urine, we achieved relative enrichment of known prostate and prostate cancer‐associated EV‐resident proteins. Our approach provides a promising strategy for global proteomic analyses of urinary EVs. [ABSTRACT FROM AUTHOR]

Testicular germ cell tumors (TGCTs) are a diverse group of neoplasms that are derived from dysfunctional fetal germ cells and can also present in extragonadal sites. The genetic drivers underlying malignant transformation of TGCTs have not been fully elucidated so far. The aim of the present study is to clarify the functional role and regulatory mechanism of miR‐196a‐5p in TGCTs. We demonstrated that miR‐196a‐5p was downregulated in TGCTs. It can inhibit the proliferation, migration, and invasion of testicular tumor cell lines including NT‐2 and NCCIT through targeting the NR6A1 gene, which we proved its role in promotion of cell proliferation and repression of cellular junction and aggregation. Mechanistically, NR6A1 inhibited E‐cadherin through binding with DR0 sites in the CDH1 gene promoter and recruiting methyltransferases Dnmt1. Further, NR6A1 promoted neuronal marker protein MAP2 expression in RA‐induced neurodifferentiation of NT‐2 cells and testicular tumor xenografts. Clinical histopathologically, NR6A1 was positively correlated with MAP2, and negatively correlated with E‐cadherin in TGCTs. These findings revealed that the miR‐196a‐5p represses cell proliferation, migration, invasion, and tumor neurogenesis by inhibition of NR6A1/E‐cadherin signaling axis, which may be a potential target for diagnosis and therapy of TGCTs. [ABSTRACT FROM AUTHOR]

Background: Myocardial ischemia/reperfusion (MI/R) injury imposes devastating cardiovascular sequelae in particular cardiac dysfunction as a result of restored blood flow. However, the mechanism behind MI/R injury remains elusive. Mitochondrial ubiquitin ligase (MITOL/MARCH5) is localized at the mitochondria‐ER contact site and may be activated in response to a variety of pathophysiological processes, such as apoptosis, mitochondrial injury, ER stress, hypoxia, and reactive oxygen species (ROS) generation. Irisin as a cleaved product of fibronectin type III domain‐containing protein 5 (FNDC5) displays cardioprotection in diverse cardiac diseases. Methods: This study was designed to examine the role of irisin and MITOL in MI/R injury. Male C57BL/6J mice (8‐10‐week‐old) were administered adenovirus MITOL shRNA through intracardiac injection followed by MI/R surgery through ligation and release the slipknot of cardiac left anterior descending coronary artery. Results: Our results showed that irisin improved myocardial function in the face of MI/R injury as evidenced by reduced myocardial infarct size, apoptotic rate, serum lactate dehydrogenase (LDH), ROS generation, and malondialdehyde (MDA) levels as well as lessened ER stress injury. Moreover, our results indicated that protective role of irisin was mediated by upregulation of MITOL. Irisin also protected H9c2 cells against simulated I/R through negating ER stress, apoptosis, ROS and MDA levels, as well as facilitating superoxide dismutase (SOD) by way of elevated MITOL expression. Conclusions: To this end, our data favored that irisin pretreatment protects against MI/R injury, ER stress, ROS production, and mitochondrial homeostasis through upregulation of MITOL. These findings depicted the therapeutic potential of irisin and MITOL in the management of MI/R injury in patients with ST‐segment elevation. [ABSTRACT FROM AUTHOR]

Increasing evidence indicates that extracellular vesicles (EVs) play an important role in cancer cell‐to‐cell communication. The Epstein‐Barr virus (EBV)‐encoded latent membrane protein 1 (LMP1), which is closely associated with nasopharyngeal carcinoma (NPC) pathogenesis, can trigger multiple cell signaling pathways that affect cell progression. Several reports have shown that LMP1 promotes EV secretion, and LMP1 trafficking by EVs can enhances cancer progression and metastasis. However, the molecular mechanism by which LMP1 promotes EV secretion is not well understood. In the present study, we found that LMP1 promotes EV secretion by upregulated syndecan‐2 (SDC2) and synaptotagmin‐like‐4 (SYTL4) through nuclear factor (NF)‐κB signaling in NPC cells. Further study indicated that SDC2 interacted with syntenin, which promoted the formation of the EVs, and SYTL4 is associated with the release of EVs. Moreover, we found that stimulation of EV secretion by LMP1 can enhance the proliferation and invasion ability of recipient NPC cells and tumor growth in vivo. In summary, we found a new mechanism by which LMP1 upregulates SDC2 and SYTL4 through NF‐κB signaling to promote EV secretion, and further enhance cancer progression of NPC. [ABSTRACT FROM AUTHOR]

Radioresistance has been one of the impediments to effective nasopharyngeal carcinoma (NPC) therapy in clinical settings. Epstein‐Barr virus (EBV) encoded latent membrane protein 1 (LMP1) is expressed in NPC and has potent effects on radioresistance. It has been detected in extracellular vesicles (EVs) or exosomes and shown to promote tumor proliferation and invasive potential. However, whether LMP1‐positive EVs can confer radioresistance to cancer cells and the mechanism used to promote radioresistance need to be elucidated. In this study, the data showed that EVs derived from LMP1‐positive NPC cells could induce recipient NPC cell proliferation and invasion and suppress apoptosis, especially promoting radioresistance. In addition, LMP1 could increase the secretion of LMP1‐positive EVs. Furthermore, transmitted LMP1 subsequently performed its oncogenic functions through activating P38 MAPK signaling in recipient cells, and inhibiting P38 activity could efficaciously restore the sensitivity of NPC cells to ionizing radiation (IR). Finally, we found that LMP1‐positive EVs could promote tumor growth and P38 inhibition eliminates this promoting effect in vivo, and EV formation is associated with a poor prognosis in NPC patients. These results showed that a few cells expressing LMP1 could enhance the radioresistance of NPC cells through potentially impacting the infected host and also modulating the tumor microenvironment. [ABSTRACT FROM AUTHOR]

Complete plastid genome (plastome) sequences and nuclear ribosomal DNA (nrDNA) regions have been proposed as candidates for the next generation of DNA barcodes for plant species discrimination. However, the efficacy of this approach still lacks comprehensive evaluation. We carried out a case study in the economically important but phylogenetically and taxonomically difficult genus Panax (Araliaceae). We generated a large data set of plastomes and nrDNA sequences from multiple accessions per species. Our data improved the phylogenetic resolution and levels of species discrimination in Panax, compared to any previous studies using standard DNA barcodes. This provides new insights into the speciation, lineage diversification and biogeography of the genus. However, both plastome and nrDNA failed to completely resolve the phylogenetic relationships in the Panax bipinnatifidus species complex, and only half of the species within it were recovered as monophyletic units. The results suggest that complete plastome and ribosomal DNA sequences can substantially increase species discriminatory power in plants, but they are not powerful enough to fully resolve phylogenetic relationships and discriminate all species, particularly in evolutionarily young and complex plant groups. To gain further resolving power for closely related species, the addition of substantial numbers of nuclear markers is likely to be required. [ABSTRACT FROM AUTHOR]

Hypertension contributes to the high cardiac morbidity and mortality. Although oxidative stress plays an essential role in hypertensive heart diseases, the mechanism remains elusive. Transgenic mice with cardiac overexpression of metallothionein, a heavy metal‐binding scavenger, were challenged with NG‐nitro‐L‐arginine methyl ester (L‐NAME) for 14 days prior to measurement of myocardial contractile and intracellular Ca2+ anomalies as well as cell signalling mechanisms using Western blot and immunofluorescence analysis. L‐NAME challenge elicited hypertension, macrophage infiltration, oxidative stress, inflammation and cardiac dysfunction manifested as increased proinflammatory macrophage marker F4/80, interleukin‐1β (IL‐1β), intracellular O2- production, LV end systolic and diastolic diameters as well as depressed fractional shortening. L‐NAME treatment reduced mitochondrial membrane potential (MMP), impaired cardiomyocyte contractile and intracellular Ca2+ properties as evidenced by suppressed peak shortening, maximal velocity of shortening/relengthening, rise in intracellular Ca2+, along with elevated baseline and peak intracellular Ca2+. These unfavourable mechanical changes and decreased MMP (except blood pressure and macrophage infiltration) were alleviated by overexpression of metallothionein. Furthermore, the apoptosis markers including BAD, Bax, Caspase 9, Caspase 12 and cleaved Caspase 3 were up‐regulated while the anti‐apoptotic marker Bcl‐2 was decreased by L‐NAME treatment. Metallothionein transgene reversed L‐NAME‐induced changes in Bax, Bcl‐2, BAD phosphorylation, Caspase 9, Caspase 12 and cleaved Caspase 3. Our results suggest that metallothionein protects against L‐NAME‐induced myocardial contractile anomalies in part through inhibition of apoptosis. [ABSTRACT FROM AUTHOR]

Aging is accompanied with unfavorable geometric and functional changes in the heart involving dysregulation of Akt and autophagy. This study examined the impact of Akt2 ablation on life span and cardiac aging as well as the mechanisms involved with a focus on autophagy and mitochondrial integrity. Cardiac geometry, contractile, and intracellular Ca2+ properties were evaluated using echocardiography, IonOptix® edge-detection and fura-2 techniques. Levels of Sirt1, mitochondrial integrity, autophagy, and mitophagy markers were evaluated using Western blot. Our results revealed that Akt2 ablation prolonged life span (by 9.1%) and alleviated aging (24 months)-induced unfavorable changes in myocardial function and intracellular Ca2+ handling ( SERCA2a oxidation) albeit with more pronounced cardiac hypertrophy (58.1%, 47.8%, and 14.5% rises in heart weight, wall thickness, and cardiomyocyte cross-sectional area). Aging downregulated levels of Sirt1, increased phosphorylation of Akt, and the nuclear transcriptional factor Foxo1, as well as facilitated acetylation of Foxo1, the effects of which (except Sirt1 and Foxo1 acetylation) were significantly attenuated or negated by Akt2 ablation. Advanced aging disturbed autophagy, mitophagy, and mitochondrial integrity as evidenced by increased p62, decreased levels of beclin-1, Atg7, LC3B, BNIP3, PTEN-induced putative kinase 1 ( PINK1), Parkin, UCP-2, PGC-1α, and aconitase activity, the effects of which were reversed by Akt2 ablation. Aging-induced cardiomyocyte contractile dysfunction and loss of mitophagy were improved by rapamycin and the Sirt1 activator SRT1720. Activation of Akt using insulin or Parkin deficiency prevented SRT1720-induced beneficial effects against aging. In conclusion, our data indicate that Akt2 ablation protects against cardiac aging through restored Foxo1-related autophagy and mitochondrial integrity. [ABSTRACT FROM AUTHOR]

Although reperfusion is the most effective therapy for patients with acute myocardial infarction, reperfusion injury limits the therapeutic effects of early reperfusion. Oxidative stress plays a crucial role in myocardial ischaemia/reperfusion (I/R) injury. Melatonin, a circulating hormone, is well-known as an antioxidant in cardiovascular diseases. In this short communication, we show that melatonin significantly improves post-ischaemic cardiac function, reduces infarct size and decreases oxidative stress. Furthermore, melatonin markedly increases AMPK activation and Nrf2 nuclear translocation. Nevertheless, these melatonin-induced changes are abrogated by compound C. In addition, ML-385, an Nrf2 inhibitor, also withdraws the antioxidative effects of melatonin but has little effect on AMPK activation. In conclusion, our results demonstrate that melatonin alleviates myocardial I/R injury by inhibiting oxidative stress via the AMPK/Nrf2 signalling pathway., (© 2021 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)