Downregulation of renal CYP-derived eicosanoid synthesis in rats with diet-induced hypertension

The incidence of essential hypertension increases with obesity; however, the mechanisms that link obesity with hypertension are unclear. Renal cytochrome P450 (CYP)-derived eicosanoids--hydroxyeicosatetraenoic acids (HETEs), epoxyeicosatrienoic acids (EETs), and dihydroxyeicosatrienoic acids (DHETs)--have been shown to play an important role in the regulation of renal function, vascular tone, and blood pressure. The objective of this study was to examine CYP-derived eicosanoid synthesis in the different renal zones (cortex, medulla, and papilla) of rats fed a high fat diet (HF). Male Sprague-Dawley rats were fed a HF diet or regular rat chow for 10 weeks. After 10 weeks, HF rats showed significantly higher systolic blood pressure, body weight, and fat:body weight ratio. The renal omega-hydroxylase activity was decreased by 46% in cortex, 43% in medulla, and 46% in papilla of HF rats. The renal epoxygenase activity was decreased by 46% in cortex, 31% in medulla, and 56% in papilla of HF rats. Interestingly, the changes in the rate of 20-HETE and EET formation in different renal zones were consistent with the levels of expression of CYP4A and CYP2C23 proteins, respectively. Furthermore, there were no significant changes in the synthesis of these metabolites in the renal microvessels. These results demonstrate that HF diet causes the downregulation of CYP4A and CYP2C23 in renal tubules, and these proteins are responsible for renal 20-HETE and EET formation. The reduction in the synthesis of these eicosanoids may play an important role in the regulation of renal function and blood pressure in obesity-induced hypertension.     

Mitochondrial sources of H2O2 generation play a key role in flow-mediated dilation in human coronary resistance arteries

We previously showed that hydrogen peroxide (H2O2) contributes to flow-induced dilation in human coronary resistance arteries (HCRAs); however, the source of this H2O2 is not known. We hypothesized that the H2O2 is derived from superoxide (O2*-) generated by mitochondrial respiration. HCRAs were dissected from right atrial appendages obtained from patients during cardiac surgery and cannulated with micropipettes. H2O2-derived radicals and O2*- were detected by electron spin resonance (ESR) using BMPO as the spin trap and by histofluorescence using hydroethidine (HE, 5 micromol/L) and dichlorodihydrofluorescein (DCFH, 5 micromol/L). Diameter changes to increases in pressure gradients (20 and 100 cm H2O) were examined in the absence and the presence of rotenone (1 micromol/L), myxothiazol (100 nmol/L), cyanide (1 micromol/L), mitochondrial complex I, III, and IV inhibitors, respectively, and apocynin (3 mmol/L), a NADPH oxidase inhibitor. At a pressure gradient of 100 cm H2O, ubisemiquinone and hydroxyl radicals were detected from effluents of vessels. Including superoxide dismutase and catalase in the perfusate reduced the ESR signals. Relative ethidium and DCFH fluorescence intensities in HCRAs exposed to flow were enhanced (1.45+/-0.15 and 1.57+/-0.12, respectively compared with no-flow) and were inhibited by rotenone (0.87+/-0.17 and 0.95+/-0.07). Videomicroscopic studies showed that rotenone and myxothiazol blocked flow-induced dilation (% max. dilation at 100 cm H2O: rotenone, 74+/-3% versus 3+/-13%; myxothiazol, 67+/-3% versus 28+/-4%; P<0.05). Neither cyanide nor apocynin altered flow-induced dilation. These results suggest that shear stress induced H2O2 formation, and flow-induced dilation is derived from O2*- originating from mitochondrial respiration.     

连续护理对妊娠期糖尿病患者妊娠结局的干预效果研究

目的探讨连续护理对妊娠期糖尿病（GDM）患者妊娠结局的干预效果。方法选取在产科门诊经OGTT试验确诊为GDM,并在我院产检、分娩的患者160例,分为干预组和对照组,每组各80例。对照组采用传统护理;干预组在传统护理的基础上采用个体化连续护理干预方案,合理应用教育指导、饮食疗法、适度运动锻炼、血糖监测和用药指导等干预,并对出院后的患者进行全程管理。统计两组孕妇孕期及产后并发症和新生儿并发症的发生率以及产后42d血糖控制情况,作为评价GDM患者妊娠结局的观察指标。在完成全程管理、结束本次连续护理的研究计划时,让患者自行填写糖尿病患者生存质量特异性量表（DQOL）。结果两组孕妇孕期及产后并发症和新生儿并发症发生率、血糖控制情况以及DQOL结果显示,干预组均显著优于对照组。结论连续护理应用于GDM患者,可有效提高妊娠质量,改善妊娠结局。     

急性冠脉综合征患者的知识、态度和信念水平在抑郁应对中的作用

目的探讨急性冠脉综合征(acute coronary syndrome,ACS)患者的知识、态度和信念水平在抑郁情绪和应对方式之间的中介效应,为ACS患者的健康教育提供理论依据。方法采用方便抽样法选取2012年6-9月在山东省济南市4所三级甲等医院心内科住院的ACS患者177例,采用一般资料问卷、患者健康问卷、ACS反应指数量表和特质应对方式问卷对患者进行调查。结果 ACS患者健康问卷平均得分为(4.72±4.72)分,应对方式中积极应对和消极应对的平均得分分别为(20.92±5.93)和(33.39±7.00)分,反应指数量表中知识、态度、信念各维度平均得分分别为(12.05±2.86)、(14.32±3.03)、(22.71±3.81)分。ACS患者抑郁、反应指数、应对方式之间存在相关性。知识水平在积极应对和抑郁中起到部分中介效应,在消极应对和抑郁中起到完全中介效应,中介效应依次为0.04和0.03,分别占总效应的35.74%和60.62%。结论在应对方式对抑郁情绪的作用中,有一部分是通过知识水平来实现的;因此,通过针对性的健康教育提高ACS患者的知识水平有利于患者采取积极应对的方式以缓解抑郁情绪。     

蛛网膜下隙出血患者水钠紊乱的影响因素及护理

目的探讨蛛网膜下隙出血(subarachnoid hemorrhage,SAH)患者水钠紊乱的影响因素及护理对策。方法回顾性分析并总结西安交通大学医学院第一附属医院2007年1月至2012年6月收治的183例SAH患者的临床资料。结果水钠紊乱多发生在SAH患者发病后的5~8d内,主要表现为低血钠,占85.5%。SAH患者水钠紊乱与Hunt-Hess分级、抗利尿激素分泌异常综合征(inappropriate antidiuretic hormone secretion,SIADH)、脑盐耗综合征(cerebral salt wasting syndrome,CSWS)及颅内压增高有关。结论护理人员应高度重视对SAH患者水钠代谢的持续监护,针对产生水钠紊乱的影响因素及早采取有效的护理对策,从而改善SAH患者的预后。     

Detection of promoter methylation status of suppressor of cytokine signaling 3 (SOCS3) in tissue and plasma from Chinese patients with different hepatic diseases

SOCS3 as an important negative regulator of IL6/JAK/STAT3 signaling pathway may be early critical determinants of carcinogenesis. This study aimed to explore the aberrant promoter methylation of SOCS3 gene in circulating DNA as a noninvasive biomarker for screening hepatocellular carcinoma (HCC) high-risk individuals and for prognosis of HCC patients after partial hepatectomy. We detected its methylation status in 116 liver tissues and 326 plasma specimens of different hepatic diseases and healthy subjects, and its mRNA and protein expression in tissues. Higher methylation rate was remarkably detected in HCC (47.92%), compared with corresponding non-tumor (25.0%), liver cirrhosis (LC) (10.0%), benign liver diseases (0%) and normal liver tissues (0%) (all P < 0.05). SOCS3 mRNA level was significantly lower in methylated HCC tissues (P < 0.05). The expressions of SOCS3 and pSTAT3 were affected by methylation status. Correlation and consistency of SOCS3 methylation were found between cancer tissue and corresponding plasma (P < 0.001, κ = 0.747). The detection rate of plasma for HCC reached 73.91%, with no false positive error. SOCS3 methylation status both in tissue and plasma was significantly associated with AFP400, tumor size, tumor differentiation, LC, metastasis and recurrence (all P < 0.05). Patients with SOCS3 methylation were followed up a markedly poorer prognosis than those unmethylated for disease-free survival (P < 0.05). These data indicate that methylation status of SOCS3 in plasma cell-free DNA can correctly reflect that in tissue DNA and be used as a noninvasive potential biomarker for chronic liver disease monitoring, predicting the degree of malignancy and poor prognosis of HCC.     

Activation and Migration of Adventitial Fibroblasts Contributes to Vascular Remodeling

The rat carotid artery balloon injury model was used to prove the activation and migration of adventitial fibroblasts. We found that at day 7 after injury, adventitial fibroblasts proliferated, transformed into myofibroblasts under transmission electron microscopy in the model group. Simultaneously, we proved that the adventitial cells migrated to the media and intima on seventh day after injury by directly labeled the adventitial cells by the in vivo gene transfer technique. Moreover, we captured the precise moment when the adventitial fibroblasts migrated from the adventitia to the media through the external elastic plate under transmission electron microscope. This study provides direct evidences that adventitial fibroblasts activate and migrate to the media and intima, then actively take part in revascularization. Anat Rec, 301:1216–1223, 2018. © 2018 Wiley Periodicals, Inc.     

Substance P increases CCN2 dependent on TGF-beta yet Collagen Type I via TGF-beta1 dependent and independent pathways in tenocytes

Transforming growth factor beta 1 (TGFbeta-1) and connective tissue growth factor (CCN2) are important mediators of tissue repair and fibrosis, with CCN2 functioning as a downstream mediator of TGFβ-1. Substance P (SP) is also linked to collagen production in tenocytes. A link between SP, TGFbeta-1 and CCN2 has yet to be established in tenocytes or fibrogenic processes. We sought to determine whether SP induces tenocyte proliferation, CCN2, or collagen production via TGFbeta-1 signaling or independently in rat primary tenocytes. Tenocytes were isolated from rat tendons, cultured and stimulated by SP and/or TGFbeta-1. Cultured cells expressed proteins characteristic of tenocytes (vimentin and tenomodulin) and underwent increased proliferation dose dependently after SP and TGFbeta-1 treatments, alone or combined (more than SP alone when combined). SP induced TGFbeta-1 expression in tenocytes in both dose- and time-dependent manners. SP and TGFbeta-1, alone or combined, stimulated CCN2 expression in tenocytes and their supernatants after both 24 and 48 h of stimulation; a response blocked with addition of a TGFbeta-1 receptor inhibitor. In contrast, SP potentiated collagen type I secretion by tenocytes, a response abrogated by the TGFbeta-1 receptor inhibitor after 48 h of stimulation, but not after the shorter 24 h of stimulation. Our findings suggest that both SP and TGFbeta-1 can stimulate tenocyte fibrogenic processes, albeit differently. TGFbeta-1 pathway signaling was involved in CCN2 production at all time points examined, while SP induced collagen type I production independently prior to the onset of signaling through the TGFbeta-1 pathway.     

DNMT3A controls miR-200b in cardiac fibroblast autophagy and cardiac fibrosis

Aim and objective

Regulation of microRNA gene expression by DNA methylation may represent a key mechanism to drive cardiac fibrosis progression. Cardiac fibroblast autophagy is the primary source of cardiac fibrosis, but the mechanisms underlying this process are incompletely understood. Here we found that DNMT3A suppression of the microRNA-200b (miR-200b) through pathway leads to cardiac fibroblast autophagy in cardiac fibrosis.

Methods

To understand the impact of DNMT3A on miR-200b at cardiac fibrosis, the rat cardiac fibrosis model was established via the abdominal aortic coarctation. Cardiac fibroblasts (CFs) were harvested from SD neonate rats and cultured. The expression of DNMT3A, miR-200b, collagen I was measured by western blotting, immunohistochemistry and qRT-PCR. Gain- or loss-of-function approaches were used to manipulate DNMT3A and miR-200b.

Results

DNMT3A level was upregulated and negatively correlated with miR-200b expression in fibrosis tissues and cardiac fibroblast. We found that autophagy was activated by miR-200b inhibitor and inactivated by miR-200b mimic in the rat cardiac fibroblast. Knockdown of DNMT3A notably increased the expression of miR-200b.

Conclusions

Taken together, these findings indicate that DNMT3A regulation of miR-200b controls cardiac fibroblast autophagy during cardiac fibrosis and provide a basis for the development of therapies for cardiac fibrosis.