Accumulating evidence revealed that mesenchymal stem cells (MSCs) confer cardioprotection against myocardial infarction (MI). However, the poor survival and engraftment rate of the transplanted cells limited their therapeutic efficacy in the heart. The enhanced leptin production associated with hypoxia preconditioning contributed to the improved MSCs survival. Mitochondrial integrity determines the cellular fate. Thus, we aimed to investigate whether leptin can enhance mitochondrial integrity of human MSCs (hMSCs) to protect against various stress. In vivo, transplantation of leptin-overexpressing hMSCs into the infarcted heart resulted in improved cell viability, leading to enhanced angiogenesis and cardiac function. In vitro, pretreatment of hMSCs with recombinant leptin (hMSCs-Lep^pre) displayed improved cell survival against severe ischemic condition (glucose and serum deprivation under hypoxia), which was associated with increased mitochondrial fusion. Subsequently, Optic atrophy 1 (OPA1), a mitochondrial inner membrane protein that regulates fusion and cristae structure, was significantly elevated in the hMSCs-Lep^pre group, and the protection of leptin was abrogated by targeting OPA1 with a selective siRNA. Furthermore, OMA1, a mitochondrial protease that cleaves OPA1, decreased in a leptin-dependent manner. Pretreatment of cells with an inhibitor of the proteasome (MG132), prevented leptin-induced OMA1 degradation, implicating the ubiquitination/proteasome system as a part of the protective leptin pathway. In addition, GSK3 inhibitor (SB216763) was also involved in the degradation of OMA1. In conclusion, in the hostile microenvironment caused by MI, (a) leptin can maintain the mitochondrial integrity and prolong the survival of hMSCs; (b) leptin-mediated mitochondrial integrity requires phosphorylation of GSK3 as a prerequisite for ubiquitination-depended degradation of OMA1 and attenuation of long-OPA1 cleavage. Thus, leptin targeting the GSK3/OMA1/OPA1 signaling pathway can optimize hMSCs therapy for cardiovascular diseases such as MI.

Glioma is the most common primary brain tumor and its prognosis is poor. Despite surgical removal, glioma is still prone to recurrence because it grows rapidly in the brain, is resistant to chemotherapy, and is highly aggressive. Therefore, there is an urgent need for a platform to study the cell dynamics of gliomas in order to discover the characteristics of the disease and develop more effective treatments. Although 2D cell models and animal models in previous studies have provided great help for our research, they also have many defects. Recently, scientific researchers have constructed a 3D structure called Organoids, which is similar to the structure of human tissues and organs. Organoids can perfectly compensate for the shortcomings of previous glioma models and are currently the most suitable research platform for glioma research. Therefore, we review the three methods currently used to establish glioma organoids. And introduced how they play a role in the diagnosis and treatment of glioma. Finally, we also summarized the current bottlenecks and difficulties encountered by glioma organoids, and the current efforts to solve these difficulties.

Background: The job performance of individual employees determines the overall performance of an organization, and organizational support is known as an important resource at the organizational level to enhance job performance. Although nursing scholars have confirmed the crucial role of organizational support in enhancing job performance, there are no studies on whether psychological capital and organizational identification mediate the association between organizational support and job performance. The purpose of this study is to investigate the influence of organizational support, psychological capital, and organizational identification on nurses’ job performance. Methods: A cross-sectional survey was conducted among 455 nurses from 21 public hospitals in China. Instruments were perceived organizational support scale, task performance scale, contextual performance scale, Nurse Psychological Capital Questionnaire, and Organizational Identification Questionnaire. Survey data were analyzed using SPSS and AMOS, and hypotheses were tested using path model analysis. Results: Nurses’ perceived organizational support, psychological capital, organizational identification, and task/contextual performance were positively correlated in every two variables. Psychological capital played an important mediating role in perceived organizational support and task/contextual performance, as well as organizational identification. The multi-mediating effect of psychological capital and organizational identification on the relationship between organizational support and task/contextual performance were 0.14 and 0.25, respectively. Conclusions: There was a positive correlation between organizational support and job performance among nurses. Psychological support, organizational identification and contextual performance played a chain mediation role in the relationship between organizational support on task performance in nurses. Nursing managers should pay more attention to enhancing nurses’ psychological capital and organizational identification through effective interventions to improve nurses’ job performance.

Background: Lipoprotein(a) [Lp(a)] elevation is an important risk factor for coronary artery disease (CAD). However, the correlation between Lp(a) elevations and the risk of recurrent cardiovascular events in patients with established cardiovascular disease is controversial. Some studies have shown that Low-density lipoprotein cholesterol (LDL-C) levels may influence the association between Lp(a) and cardiovascular risk. Our study aims to explore the correlation between Lp(a) elevations and cardiovascular risk in patients with different LDL-C levels. Methods: We included 516 patients who received coronary stents due to acute coronary syndrome (ACS) and followed them for three years. They were divided into low-Lp(a) group and high-Lp(a) group according to Lp(a) levels, and the incidence of major adverse cardiovascular events (MACE) and acute coronary events (ACE) was compared between the two groups. Then the patients were divided into three subgroups (S1:LDL-C ≥ 1.8 mmol/L; S2:1.4 ≤ LDL-C < 1.8 mmol/L; S3:LDL-C < 1.4 mmol/L). The correlation between Lp(a) elevations and cardiovascular risk in different subgroups was analysed by Cox proportional hazards models. Results: The incidence of MACE and ACE in the high-Lp(a) group was significantly higher than those in the low-Lp(a) group (P < 0.05). Lp(a) elevations had independent prognostic value from the statistical point of view (MACE: HR = 1.63, 95%CI = 1.12–2.38, P = 0.012; ACE: HR = 1.70, 95%CI = 1.03–2.81, P = 0.037). Subgroup analysis showed that Lp(a) elevations increased cardiovascular risk when LDL-C ≥ 1.4 mmol/L. However, this correlation no longer existed when LDL-C levels were very low (< 1.4 mmol/L) (MACE: HR = 0.49, 95%CI = 0.17–1.42, P = 0.186; ACE: HR = 0.68, 95%CI = 0.18–2.61, P = 0.570). Conclusions: Lp(a) elevations are associated with recurrent cardiovascular events when LDL-C levels are high, but this association may change when LDL-C levels are extremely low. CAD patients with combination of LDL-C ≥ 1.4 mmol/L and Lp(a) elevations shall be considered as high-risk groups and require further medication for the reduction of their LDL-C levels.