Transcriptional Profile Alteration of Peripheral Blood in Chronic Hypoxia / 中国医学科学杂志(英文版)

Objective Many physiological and pathological conditions, including cyanotic congenital heart diseases (CCHD), are accompanied by chronic hypoxia, which might interfere with the transcription process. However, the transcriptome profile in peripheral blood under hypoxia is still unidentified. The present work aimed to explore the transcriptional profile alteration of peripheral blood in chronic hypoxia. Methods The present study used a chronic hypoxia rat model to simulate the hypoxic state of CCHD patients. Two groups of Sprague-Dawley rats (n=6 per group) were either exposed to hypoxia (10% O2) or normoxia (21% O2) for 3 weeks. Body weight was measured weekly. Peripheral blood was collected and total RNA was extracted for RNA-Seq at the end of the hypoxia treatment. After quality assessment, the library was sequenced by the Illumina Hiseq platform. The differentially expressed genes were screened (false discovery rate<0.05 and fold change>2). The functional annotation analysis and cluster analysis of differentially expressed genes were performed based on the adjusted P-value (padj<0.05). Results Compared with the control group, the body weight of the rats in the hypoxia group was significantly lowered (P<0.01). RNA-Seq results showed that the transcriptome patterns of the two groups had significant differences. In total, 872 genes were identified as differentially expressed. Among all, 803 genes were down-regulated, while only 69 genes were up-regulated in the hypoxia group. The functional enrichment analysis of the 872 genes showed that multiple biological processes involved, such as porphyrin-containing compound metabolic process, hemoglobin complex and oxygen transporter activity. Conclusions Our study demonstrated the transcriptional profile alteration in peripheral blood of chronic hypoxia rat model. This study provided basic data and directions to further understand the physiological and pathological changes in patients with CCHD.

Therapeutic Effects of Transthoracic Pulmonary Artery Denervation in a Rat Model of Pulmonary Arterial Hypertension / 中国循环杂志

Objectives:The aim of this study was to observe whether transthoracic pulmonary artery denervation (TPADN) could reduce the pulmonary arterial pressure and attenuate pulmonary vascular remodeling in rats with pulmonary arterial hypertension induced by monocrotaline. Methods:Twenty-four healthy male SD rats were randomly divided into control group, sham operation group and operation group (n=8 per group). Rats in sham operation group and operation group received single subcutaneous injection of monocrotaline (MCT, 60 mg/kg). After four weeks, the mean pulmonary arterial pressure (mPAP) and other hemodynamic parameters were measured with the right heart catheter in rats of these two groups. Then, operation group received the surgery of TPADN, which included thoracotomy in left 2-3 rib, exposing pulmonary artery, and removing the near connective tissue of the pulmonary artery trunk. After two weeks of operation, the mPAP and other hemodynamic parameters were measured again by the right heart catheter. The microstructure changes of the heart and pulmonary vessels was observed by immunohistochemistry and immunofluorescence. Meanwhile, RV cardiomyocyte cross-sectional area (CSA) and the right hearthy pertrophy index (RVHI= RV/[LV+S]) were used to evaluate the degree of right ventricular hypertrophy. Results:After four weeks of injection of MCT, the mPAP was significantly higher in the operation group and the sham operation group than in control group (P＜0.01). Two weeks after the surgery of TPADN, the mPAP was significantly reduced in the operation group than compared in the sham group(P＜0.01). Meanwhile, the percentage of medial thickness to outer diameter of the small pulmonary arterioles, right ventricular myocardial cell cross-sectional area and RVHI were also significantly decreased in the operation group compared to sham operation group(all P＜0.01). Conclusions:Our results show that TPADN could reduce the mean pulmonary arterial pressure and attenuate the hypertrophy of medial thickness of small pulmonary arterioles and of right ventricle in PAH rats induced by monocrotaline.