RNA-binding protein CELF6 modulates transcription and splicing levels of genes associated with tumorigenesis in lung cancer A549 cells.

CELF6 (CUGBP Elav-Like Family Member 6), a canonical RNA binding protein (RBP), plays important roles in post-transcriptional regulation of pre-mRNAs. However, the underlying mechanism of lower expressed CELF6 in lung cancer tissues is still unclear. In this study, we increased CELF6 manually in lung cancer cell line (A549) and utilized transcriptome sequencing (RNA-seq) technology to screen out differentially expressed genes (DEGs) and alternative splicing events (ASEs) after CELF6 over-expression (CELF6-OE). We found that CELF6-OE induced 417 up-regulated and 1,351 down-regulated DEGs. Functional analysis of down-regulated DEGs showed that they were highly enriched in immune/inflammation response- related pathways and cell adhesion molecules (CAMs). We also found that CELF6 inhibited the expression of many immune-related genes, including TNFSF10, CCL5, JUNB, BIRC3, MLKL, PIK3R2, CCL20, STAT1, MYD88, and CFS1, which mainly promote tumorigenesis in lung cancer. The dysregulated DEGs were also validated by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) experiment. In addition, CELF6 regulates the splicing pattern of large number of genes that are enriched in p53 signaling pathway and apoptosis, including TP53 and CD44. In summary, we made an extensive analysis of the transcriptome profile of gene expression and alternative splicing by CELF6-OE, providing a global understanding of the target genes and underlying regulation mechanisms mediated by CELF6 in the pathogenesis and development of lung cancer.

Uric acid lowering effect of Tibetan Medicine RuPeng15 powder in animal models of hyperuricemia.

OBJECTIVE: To evaluate the influence of the Tibetan medicine RuPeng15 powder (RPP15) on uric acid levels, and explore its possible mechanisms of action in hyperuricemic animal models. METHODS: Hyperuricemic mice were generated by orally administering yeast extract paste twice daily (30 g/kg) for 8 days, to mimic human hyperuricemia induced by high-protein diets. Hyperuricemic rats were generated by intraperitoneal injection of 250 mg/kg potassium oxonate to each animal 1 h before the last oral administration of test compounds, which raised the serum uric acid level by inhibiting the decomposition of uric acid. Levels of uric acid and creatinine in serum and urine were detected by the phosphotungstic acid and picric acid methods respectively, and the activity of xanthine oxidase (XOD) was assayed using a commercial test kit. RESULTS: RPP15 (0.4, 0.8, 1.2 g/kg) significantly decreased the level of serum uric acid in healthy rats (P < 0.05). Furthermore, hyperuricemic rats treated with RPP15 (0.4, 0.8, 1.2 g/kg) had lower serum uric acid levels (P < 0.05), accompanied by lower urine uric acid (P < 0.05). For the hyperuricemic mice, the levels of uric acid in the serum decreased significantly (P < 0.05) and the activity of XOD in the liver was restored to normal levels after treatment with RPP15 (P < 0.05). CONCLUSION: RPP15 (0.4, 0.8, 1.2 g/kg) demonstrated an anti-hyperuricemic effect on both healthy and hyperuricemic animals, and the mechanism is most likely associated with inhibiting the activity of XOD.

Effect of aqueous extract of sanweitanxiang powder on calcium homeostasis protein expression in ischemic-reperfusion injury rat heart.

OBJECTIVE: To investigate the underlying mechanism of reduced myocardial ischemia-reperfusion (I/R) injury in rats using the traditional Tibetan medicine Sanweitanxiang powder (SWTX). METHODS: Rats were randomly divided into six groups (n = 10) as follows: (a) propranolol dinitrate control group, given propranolol dinitrate 0.02 g/kg for 10 days before I/R, (b) SWTX with a high dose group, given SWTX 1.5 g/kg for 10 days before I/R, (c) SWTX with a medium dose group, given SWTX 1.25 g/kg for 10 days before I/R, (d) sham group (Sham), in which the rat heart was exposed by pericardiotomy but without I/R, (e) SWTX with a low dose group, given SWTX 1.0 g/kg for 10 days before I/R, and (f) I/R injury group. Rats were intragastrically pretreated with propranolol dinitrate or SWTX. After that, the operation to cause ischemia and reperfusion was conducted. The histopathologic changes of rat hearts were observed by hematoxylin and eosin staining and transmission electron microscopy. Ca2+ homeostasis protein expression was determined by western blot. RESULTS: After SWTX pretreatment, the development of ultrastructural pathological changes from IR injury was attenuated. A decrease in the expression of B-cell lymphoma 2 associated X protein, and an increase in the expression of B-cell lymphoma 2 were observed. An increased activation of extracellular signal regulated kinases were found. Compared with the sham group, the expression of sarcoplasmic reticulum calcium-ATPase, phospholamban, and calsequestrin were all up-regulated after pretreatment with SWTX. CONCLUSION: The protective mechanism of SWTX pretreatment on myocardial I/R injury might be related to its effect on maintaining the balance of calcium homeostasis in rat heart.

[The antioxidative effect of Sanwei Tanxiang powder on rats' hearts against myocardial ischemia and reperfusion injury].

OBJECTIVE: To study the effect of Sanwei Tanxiang powder on myocardial pathologic change, myocardium lipid peroxidation and antioxidation on anesthetized rats' hearts against myocardial ischemia and reperfusion injury. METHODS: A model of regional myocardial ischemia-reperfusion injury (IR) was established by 30 min ligation of the left anterior descending coronary artery followed by 40 min reperfusion in hearts of anesthetized rats'. The experimental animals were randomly divided into the sham operation, IR model group, positive control group and two dose Sanwei Tanxiang powder groups. The changes of ECG, LDH, CK, SOD, GSH-Px and MDA in the heart were measured and ultrastructural pathological changes were observed. RESULTS: In Sanwei Tanxiang groups the displacement of ST segment reduced (P < 0.05), the activity of LDH, CK decreased (P < 0.05), the activities of SOD, GSH-Px significantly increased and the contents of MDA reduced (P < 0.05). Moreover, the development of ultrastructral pathological changes obviously improved compared with the IR model group. CONCLUSION: The protective effects of Sanwei Tanxiang powder on anesthetized rats' hearts against myocardial ischemia and reperfusion injury may be related to protecting the antioxidants and inhibiting the lipid peroxidation in the myocardium.