Mst1 silencing alleviates hypertensive myocardial injury associated with the augmentation of microvascular endothelial cell autophagy.

The activation of mammalian ste20­like kinase1 (Mst1) is a crucial event in cardiac disease development. The inhibition of Mst1 has been recently suggested as a potential therapeutic strategy for the treatment of diabetic cardiomyopathy. However, whether silencing Mst1 also protects against hypertensive (HP) myocardial injury, or the mechanisms through which this protection is conferred are not yet fully understood. The present study aimed to explore the role of Mst1 in HP myocardial injury using in vivo and in vitro hypertension (HP) models. Angiotensin II (Ang II) was used to establish HP mouse and cardiac microvascular endothelial cell (CMEC) models. CRISPR/adenovirus vector transfection was used to silence Mst1 in these models. Using echocardiography, hematoxylin and eosin staining, Masson's trichrome staining, the enzyme­linked immunosorbent assay detection of inflammatory factors, the enzyme immunoassay detection of oxidative stress markers, terminal deoxynucleotidyl transferase dUTP nick­end labeling staining, scanning electron microscopy, transmission electron microscopy, as well as immunofluorescence and western blot analysis of the autophagy markers, p62, microtubule­associated proteins 1A/1B light chain 3B and Beclin­1, it was found that Ang II induced HP myocardial injury with impaired cardiac function, increased the expression of inflammatory factors, and elevated oxidative stress in mice. In addition, it was found that Ang II reduced autophagy, enhanced apoptosis, and disrupted endothelial integrity and mitochondrial membrane potential in cultured CMECs. The silencing of Mst1 in both in vivo and in vitro HP models attenuated the HP myocardial injury. On the whole, these findings suggest that Mst1 is a key contributor to HP myocardial injury through the regulation of cardiomyocyte autophagy.

Cystatin C and cardiovascular or all-cause mortality risk in the general population: A meta-analysis.

BACKGROUND: Elevated cystatin C level was associated with excessive risk of cardiovascular events and mortality in the highly cardiovascular risk populations. We conducted this meta-analysis to investigate the relationship between serum cystatin C level and cardiovascular or all-cause mortality risk in the general population. METHODS: We searched for all relevant studies published through May 2015 using PubMed, Embase, and Cochrane Library. Prospective studies that assessed the relationship between serum cystatin C level and cardiovascular or all-cause mortality risk in the general population were selected. Pooled adjust hazard risk (HR) and the corresponding 95% confidence intervals (CI) were calculated for continuous and category of cystatin C level. RESULTS: Nine studies composed of 38,854 participants were analyzed. Elevated serum cystatin C level was associated with excessive risk of all-cause mortality (HR 1.72; 95% CI 1.37-2.16) and cardiovascular mortality (HR 2.74; 95% CI 2.04-3.68) comparing the highest to lowest category of cystatin C. Each standard deviation increment in serum cystatin C level increased 32% all-cause (HR 1.32; 95% CI 1.12-1.55) and 57% cardiovascular mortality (HR 1.57; 95% CI 1.31-1.88) risk. CONCLUSIONS: Elevated serum cystatin C level is independently associated with excessive cardiovascular and all-cause mortality risk in elderly persons.

The expression and functional evidence for voltage-dependent potassium channel Kv1.3 in lymphocytes during aging in spontaneously hypertensive rats.

AIMS: Our previous studies showed that expression and functional profile of voltage-dependent potassium channels Kv1.3 were increased in lymphocytes of spontaneously hypertensive rats (SHR) compared to normotensive rats, suggesting a crucial role for lymphocyte Kv1.3 in the development of hypertension. Here, we further investigated whether the expression and functional profile of Kv1.3 was related to increased blood pressure in SHR with age of 4, 8, 16 and 24 wk. METHODS: Systolic blood pressure was measured through pressure device around the tail. mRNA and protein expression were assessed by real-time PCR and western blot in lymphocytes of SHR. Current density of Kv channels in lymphocytes was measured by patch-clamp. RESULTS: Systolic blood pressure was elevated in an age-dependent manner (ANOVA P < 0.05). mRNA and protein level of Kv1.3 were significantly increased in an age-dependent manner in lymphocyte of SHR (ANOVA P < 0.05). Moreover, the current density of Kv was dramatically enhanced in an age-dependent manner (ANOVA P < 0.05). CONCLUSION: The systolic blood pressure positively correlated with expression as well as current density of potassium channels in lymphocytes of SHR at age of 8, 16 and 24 wk. In conclusion, Kv1.3 channels were upregulated in an age-dependent manner in SHR and correlates with systolic blood pressure during aging. The present study implies that Kv1.3 blockers may be applied as a therapeutic treatment for the development of hypertension during aging.