Statins improve cardiac endothelial function to prevent heart failure with preserved ejection fraction through upregulating circRNA-RBCK1.

Heart failure with preserved ejection fraction (HFpEF) is associated with endothelial dysfunction. We have previously reported that statins prevent endothelial dysfunction through inhibition of microRNA-133a (miR-133a). This study is to investigate the effects and the underlying mechanisms of statins on HFpEF. Here, we show that statins upregulate the expression of a circular RNA (circRNA-RBCK1) which is co-transcripted with the ring-B-box-coiled-coil protein interacting with protein kinase C-1 (RBCK1) gene. Simultaneously, statins increase activator protein 2 alpha (AP-2α) transcriptional activity and the interaction between circRNA-RBCK1 and miR-133a. Furthermore, AP-2α directly interacts with RBCK1 gene promoter in endothelial cells. In vivo, lovastatin improves diastolic function in male mice under HFpEF, which is abolished by loss function of endothelial AP-2α or circRNA-RBCK1. This study suggests that statins upregulate the AP-2α/circRNA-RBCK1 signaling to suppress miR-133a in cardiac endothelial cells and prevent diastolic dysfunction in HFpEF.

The expression of Nramp1 modulates the uptake of Mycobacterium tuberculosis by macrophages through alternating inflammatory responses.

Natural-resistance-associated macrophage protein-1 (NRAMP1) is a transmembrane protein of the mammalian SLC11 gene family. Previously, genome-wide association study (GWAS) have shown that the single nucleotide polymorphisms (SNPs) of NRAMP1 are associated with human susceptibility to tuberculosis (TB), and the detection of clinical samples have demonstrated that the expression levels of NRAMP1 are concomitant with the susceptibility to TB in humans and cows, but underlying mechanism is unknown. In this study, we completed a series of experiments to investigate how the expression of Nramp1 affects the infection of macrophages with Mycobacterium tuberculosis (Mtb). We found that the increase of Nramp1 expression induced the decrease of Mtb infection efficiency and the higher-level expression of pro-inflammatory cytokines and chemokines, However, the knockdown of Nramp1 promoted the efficiency of bacilli infection to macrophages and induced lower-levels of expression of pro-inflammatory cytokines and chemokines. Collectively, the results in this study demonstrated that the levels of Nramp1 expression affect Mtb infection of macrophage and regulate pro-inflammatory responses of macrophages to Mtb infection, indicating the population with the low-expression level of NRAMP1 predispose to Mtb infection and TB development, and suggesting SNPs in NRAMP1 modulate the host susceptibility to TB through its regulation of NRAMP1 expression.

Prevalence and clinical implications of polypharmacy and potentially inappropriate medication in elderly patients with heart failure: results of six months' follow-up.

OBJECTIVES: To investigate the prevalence of polypharmacy and potentially inappropriate medication (PIM) in elderly patients with heart failure (HF) and their impact on readmission and mortality. METHODS: We conducted a study of 274 participants aged 60 years or older with HF. The prevalence of polypharmacy (defined as the use of five or more medications) was calculated, and the 2019 American Geriatrics Society Beers criteria were applied to access PIMs. Medications and PIMs were characterized at admission and discharge, and changes in prescriptions during hospitalization were compared. The impact of polypharmacy and PIM on readmission and mortality were investigated. RESULTS: The median age of this study population was 68 years old. The median number of prescribed drugs was 7 at admission and 10 at discharge. At discharge, 99.27% of all patients were taking five or more drugs. The incidence of composite endpoint and cardiovascular readmission increased with the number of polypharmacy within 6 months. The use of guideline-directed medical therapy reduced the incidence of composite endpoint events and cardiovascular readmission, while the use of non-cardiovascular medications increased the composite endpoint events. The frequency of PIMs was 93.79% at discharge. The incidence of composite endpoint events increased with the number of PIMs. "PIMs in older adults with caution" increased cardiovascular readmission and "PIMs based on kidney function" increased cardiovascular mortality. Several comorbidities were associated with cardiovascular mortality or non-cardiovascular readmission. CONCLUSIONS: Polypharmacy and PIM were highly prevalent in elderly patients with HF, and their use was associated with an increased risk of composite endpoint events, readmission and mortality. Non-cardiovascular medications, "PIMs in older adults with caution", "PIMs based on kidney function" and several comorbidities were important factors associated with hospital readmission and mortality. Our findings highlight the importance of medication optimization in the management of HF in elderly patients.

Up-regulation of paired-related homeobox 2 promotes cardiac fibrosis in mice following myocardial infarction by targeting of Wnt5a.

Cardiac fibrosis is a key factor to determine the prognosis in patient with myocardial infarction (MI). The aim of this study is to investigate whether the transcriptional factor paired-related homeobox 2 (Prrx2) regulates Wnt5a gene expression and the role in myocardial fibrosis following MI. The MI surgery was performed by ligation of left anterior descending coronary artery. Cardiac remodelling was assessed by measuring interstitial fibrosis performed with Masson staining. Cell differentiation was examined by analysis the expression of alpha-smooth muscle actin (α-SMA). Both Prrx2 and Wnt5a gene expressions were up-regulated in mice following MI, accompanied with increased mRNA and protein levels of α-SMA, collagen I and collagen III, compared to mice with sham surgery. Adenovirus-mediated gene knock down of Prrx2 increased survival rate, alleviated cardiac fibrosis, decreased infarction sizes and improved cardiac functions in mice with MI. Importantly, inhibition of Prrx2 suppressed ischaemia-induced Wnt5a gene expression and Wnt5a signalling. In cultured cardiac fibroblasts, TGF-ß increased gene expressions of Prrx2 and Wnt5a, and induced cell differentiations, which were abolished by gene silence of either Prrx2 or Wnt5a. Further, overexpression of Prrx2 or Wnt5a mirrored the effects of TGF-ß on cell differentiations of cardiac fibroblasts. Gene silence of Wnt5a also ablated cell differentiations induced by Prrx2 overexpression in cardiac fibroblasts. Mechanically, Prrx2 was able to bind with Wnt5a gene promoter to up-regulate Wnt5a gene expression. In conclusions, targeting Prrx2-Wnt5a signalling should be considered to improve cardiac remodelling in patients with ischaemic heart diseases.

Berberine suppresses the ectopic expression of miR-133a in endothelial cells to improve vascular dementia in diabetic rats.

Objective: Vascular dementia is the second leading cause of dementia, which is strongly associated with diabetes. Ectopic expression of miR-133a in endothelial cells is involved in endothelial dysfunction in diabetes. Whether berberine, as a natural product in Coptis chinensis, improves vascular dementia induced by diabetes remains unknown.Methods: Diabetes and subsequent vascular dementia were induced in rats by injecting streptozotocin (50 mg/kg/day) for five consecutive days. The expression of miR-133a was determined by fluorescence in situ hybridization. The learning and memory were evaluated by step-down, step-through, and morris water maze (MWM) tests.Results: In streptozotocin-injected rats, hyperglycemia dramatically induced miR-133a ectopic expressions in vascular endothelium, reduced GTPCH1 gene expressions and BH4 levels, which were reversed by berberine administration (1.0 g/kg/day, 8 weeks). Hyperglycemia also inhibited acetylcholine-induced vasorelaxation in middle cerebral artery and reduced blood supply to the brain, which were bypassed by berberine. Ex vivo studies indicated that miR-133a agomirs abolished these beneficial effects of berberine on acetylcholine-induced vasorelaxation, while supplement of L-sepiapterin prevented endothelial dysfunction in middle cerebral artery isolated from rats. By performing step-down, step-through, and MWM tests, we observed that hyperglycemia significantly caused the impairments of learning and memory in streptozotocin-injected rats. Importantly, these aberrant phenotypes in diabetic rats were normalized by berberine therapy. Finally, berberine reduced miR-133a expression, and increased both BH4 levels and NO production in cultured endothelial cells treated with high glucose.Conclusion: Berberine improves vascular dementia in diabetes, which is possibly related to the suppression of miR-133a ectopic expression in endothelial cells.

Correlation between serum lactadherin and pulse wave velocity and cardiovascular risk factors in elderly patients with type 2 diabetes mellitus.

AIMS: This study was carried out with the purpose of investigating the association between serum lactadherin, monocyte chemoattractant protein 1 (MCP-1), tumor necrosis factor alpha (TNFα) and carotid-femoral pulse wave velocity (PWV) in elderly patients with type 2 diabetes mellitus (T2DM). METHODS: A total of 105 subjects including 27 T2DM patients without vascular complications (DM), 28 T2DM patients with vascular complications (DC), 25 elderly healthy volunteers (older) and 25 younger healthy volunteers (younger) were recruited into the study. Carotid-femoral PWV was measured using an automatic device. Serum lactadherin, MCP-1 and TNFα were determined by enzyme linked immunosorbent assay. RESULTS: PWV and lactadherin, MCP-1 and TNFα were significantly higher in DM and DC groups than those of older and younger groups. PWV and lactadherin were higher in older group than those of younger group. Moreover, lactadherin was significantly correlated with MCP-1, TNFα, PWV, HbA1c and 2 h postprandial blood glucose (P2hBG) (P<0.05). In multivariate regression analysis, the independent determinants of lactadherin were HbA1c, P2hBG and age (P<0.05). CONCLUSIONS: These findings underscore that lactadherin is correlated with poor blood glucose control and diabetic vascular complications.