Next, we found that SLI has a bidirectional regulatory effect on autophagy early-stage (24h) cerebral ischaemia promotes the activation of autophagy and developmental-stage (72h) cerebral ischaemia has an inhibitory effect. SLI enhanced I/R-induced autophagy as evidenced by the increased expression level of the autophagy marker protein LC3Ⅱ, as well as the decreased expression of mTOR and the autophagy substrate protein p62, but there was no change in lysosomal activity at 24h after I/R-induced injury. Moreover, SLI also inhibited excessive activation of autophagy at 72h after I/R-induced injury, which manifested as downregulating LC3Ⅱ expression, upregulating mTOR and p62 expression, and inhibiting lysosomal activity.
SLI has a protective effect on cerebral ischaemia/reperfusion injury, which may be mediated by the autophagy-lysosome pathway.
SLI has a protective effect on cerebral ischaemia/reperfusion injury, which may be mediated by the autophagy-lysosome pathway.The nucleolus functions as the cellular hub for the initiation and early steps of ribosome biogenesis. Ribosomes are key components of the translation machinery and, accordingly, their abundance needs to be adjusted to the cellular energy status. Further, to ensure translational fidelity, the integrity and quality of ribosomes needs to be monitored under conditions of cellular stress. Stressful insults, such as nutrient, genotoxic or proteotoxic stress, interfere with ribosome biogenesis and activate a cellular response referred to as nucleolar stress. This nucleolar stress response typically affects nucleolar integrity and is intricately linked to the activation of protein quality control pathways, including (i) the ubiquitin proteasome system (UPS) and (ii) the autophagy machinery, to restore cellular proteostasis. Here we will review some key features of the nucleolar stress response with a particular focus on the role of the UPS and autophagy in this process.
It is unclear what role does obesity (OB) index play between blood lipid and bone mineral density (BMD).
This study recruited a total of 4,558 Chinese elders >65 years. OB indices waist circumference (WC), body mass index (BMI), waist-hip-ratio (WHR); blood lipid parameters low density lipoprotein (LDL); total cholesterol (TC), triglyceride (TG), and BMDs at femur neck (FN), total hip (TH), and lumbar spine (LS) were measured. The t-test and multiple linear regression analysis were used to detect the differences of variables. Casual inference test (CIT) were performed to test potential mediators underlying the associations between blood lipid and BMD.
The blood lipids were positively associated with BMD (p<0.05) after adjustment of age and sex (Model 1) both in total subjects and in sex-stratified subjects. The CIT showed that OB indices had significant mediation effects on the associations between blood lipid (TG and LDL) and BMD in total subjects and males. Comparably, the correlations of TG and BMD are most likely mediated by BMI and WC.
This study represented the first effort to report that OB indices, especially BMI and WC, served as significant mediators between blood lipid (TG and LDL) and BMD in Chinese elderly.
This study represented the first effort to report that OB indices, especially BMI and WC, served as significant mediators between blood lipid (TG and LDL) and BMD in Chinese elderly.Polycystic ovary syndrome (PCOS), affecting over 10% of women, is associated with insulin resistance, obesity, dyslipidaemia, fatty liver and adipose tissue dysfunction. Its pathogenesis is poorly understood and consequently treatment remains suboptimal. Prenatally androgenized (PA) sheep, a clinically realistic model of PCOS, recapitulate the metabolic problems associated with PCOS. Fibroblast Growth Factor 21 (FGF21) is a metabolic hormone regulating lipid homeostasis, insulin sensitivity, energy balance and adipose tissue function. We therefore investigated the role of FGF21 in the metabolic phenotype of PA sheep. In adolescence PA sheep had decreased hepatic expression and circulating concentrations of FGF21. Adolescent PA sheep show decreased FGF21 signalling in subcutaneous adipose tissue, increased hepatic triglyceride content, trend towards reduced fatty acid oxidation capacity and increased hepatic expression of inflammatory markers. These data parallel studies on FGF21 deficiency, suggesting that FGF21 therapy during adolescence may represent a treatment strategy to mitigate metabolic problems associated with PCOS.
Endogenously produced glucocorticoids exhibit immunomodulating properties and are of pivotal importance for sepsis outcome. Uncontrolled activation of the immune-adrenal crosstalk increases the risk of sepsis-related death. Triggering receptor expressed on myeloid cells-2 (TREM2) is richly expressed on macrophages and has been demonstrated to improve outcome of sepsis by enhancing elimination of pathogens. However, the role and mode of action of macrophage TREM2 on adrenocortical steroidogenesis remains unclear in septic shock.
The acute septic shock model was established by intraperitoneally challenging wild-type (WT) and TREM2 knock-out (Trem2
) mice with lipopolysaccharide (LPS, 30mg/kg). The mice were assessed for TREM2 expression and local inflammation in adrenal gland and for synthesis of corticotropin releasing hormone (CRH) and adrenocorticotropic hormone (ACTH) in vivo. Bone marrow-derived macrophages or macrophage-derived exosomes were isolated from WT and Trem2
mice and were co-cultured withassociate with macrophage-derived exosomes.Acquired drug-resistance, often involving downregulation or mutations in the target protein, is a major caveat in precision medicine. Understanding mechanisms of resistance to therapeutic drugs may unravel strategies to overcome or prevent them. We previously identified phorbol ester (PE) compounds such as TPA that induce Protein Kinase δ (PKCδ), thereby suppressing leukemogenesis. Here we identified erythroleukemia cell lines that resist PEs and showed that reduced PKCδ protein expression underlies drug resistance. Reduced level of PKCδ in resistant cell lines was due to its phosphorylation followed by protein degradation. Indeed, proteasome inhibition prevented PE-induced loss of PKCδ. Accordingly, a combination of TPA and the proteasome inhibitor ALLN significantly suppressed leukemia in a mouse model of leukemia. PKCδ downregulation by TPA was independent of the downstream MAPK/ERK/P38/JNK pathway. selleck Instead, expression of ubiquitin-associated and SH3 domain-containing protein b (Ubash3b) was induced by TPA, which leads to PKCδ protein dephosphorylation and degradation.selleck