Exosomal miRNA-200b-3p regulated autogenous arteriovenous fistula thrombosis in maintenance hemodialysis patients.

BACKGROUND: Autogenous arteriovenous fistula (AVF) is the best vascular hemodialysis access for terminal chronic renal failure patients but is prone to thrombosis. Pathogenic mechanisms of AVF thrombus are thus largely explored. As exosomes carry genetic content from cell of origin. We hypothesized that miRNAs in serum exosomes are promising regulators of AVF thrombosis. METHODS: Serum exosomes were isolated from maintenance hemodialysis (MHD) patient, miRNAs profile of the exosomes was obtained by high throughput sequencing, six miRNAs (miR-144-5p, miR-18a-5p, miR-200a-3p, miR-200b-3p, miR-141-3p, and miR-429) were determined as candidates examined by RT-PCR, cells transfected with miR-200b-3p mimics demonstrated significantly increased mRNA levels of VEGF and Ang-II, the relationship between miR-200b-3p and VEGF or Ang-II was performed by adual luciferase reporter assay. RESULTS: There are 43 miRNA down-regulation and 15 miRNA up-regulation between MHD group and MHD+Thrombus group, the expression levels of miR-200b-3p and miR-429 in MHD with thrombus were significantly increased (p < 0.001, p < 0.05). Inhibited miR-200b-3p expression level can increase VEGF mRNA and protein expression levels and decrease Ang-II mRNA and protein expression levels. Furthermore, we also identified that miR-200b-3p targets VEGF and Ang-II. CONCLUSION: Our study indicates that serum exosome-derived miR-200b-3p regulate VEGF and Ang-II to increase intimal hyperplasia to induce AVF thrombosis. Besides miR-200b-3p, miR-200 family may also play a regulatory role in AVF thrombosis.

Antihyperglycemic effect of the traditional Chinese scutellaria-coptis herb couple and its main components in streptozotocin-induced diabetic rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Scutellaria-coptis herb couple (SC) is the main herb couple in many traditional Chinese compound formulas used for the treatment of diabetes mellitus, which has been used to treat diabetes mellitus for thousands of years in China. In this study we provide experimental evidence for the clinical use of SC in the treatment of diabetes mellitus. AIM OF THE STUDY: To confirm the anti-diabetic effect of SC extract and its main components, and to explore its mechanism from the effect on intestinal disaccharidases by in vivo and in vitro experiment. MATERIALS AND METHODS: SC extract was prepared and the main components (namely berberine and baicalin) contained in the extract were assayed with high performance liquid chromatography (HPLC). And diabetic model rats were induced by intraperitoneal injection of streptozotocin (STZ). After grouped randomly, diabetic rats were administered SC extract, berberine, baicalin, berberine+baicalin, acarbose and vehicle for 33d, respectively. Body weight, food intake, urine volume, urine sugars, fasting plasma glucose and fasting plasma insulin were monitored to evaluate the antidiabetic effects on diabetic rats. Intestinal mucosa homogenate was prepared and the activities of intestinal disaccharidases were assayed. Moreover, oral sucrose tolerance test (OSTT) was performed and the inhibitory effects of SC extract and its main components (berberine and baicalin) on the maltase and sucrase in vitro was evaluated. RESULTS: After the treatment of SC extract and its main components, the body weight and the fasting plasma insulin level were found to be increased while food intake, urine volume, urine sugars and fasting plasma were decreased. OSTT showed that SC extract and its main components could lower the postprandial plasma glucose level of diabetic rats. Furthermore, SC extract and its main components could inhibit the activities of intestinal disaccharidases in diabetic rats, whereas only SC extract and berberine could inhibit the activity of maltase in vitro. CONCLUSIONS: According to our present findings, scutellaria-coptis herb couple (SC) possessed potent anti-hyperglycemic effect on STZ-induced diabetic rats. And SC extract and its main components exerted anti-hyperglycemic effect partly via inhibiting the increased activities of intestinal disaccharidases and elevating the level of plasma insulin in diabetic rats induced by STZ.

[Isolation and identification of brine shrimp lethal activities from Derris trifoliata].

OBJECTIVE: To study the brine shrimp lethal activities of the roots and stems from Derris trifoliata. METHODS: The biological activity of the athyl acetate extract was tested by the 2nd-instar of Artemia franciscana by the method of Silica gel column chromatography, Sephadex LH-20 column chromatography, Semipreparative HPLC, and their structures were elucidated by spectral analysis. RESULTS: Eleven compounds were isolated from the athyl acetate extract, and LD50 s of 12a-hydroxyrotenone, tephrosin, rotenone and deguelin were 0.365, 0.236, 0.060 and 0.734 microg/mL, respectively. CONCLUSION: The results of bioassay show that 12a-hydroxyrotenone, tephrosin,rotenone and deguelin have strong brine shrimp lethal activity.

Comparative pharmacokinetics of baicalin in normal and the type 2 diabetic rats after oral administration of the Radix scutellariae extract.

Radix scutellariaewas used alone or in combinationwith othermedicinal herbs in the treatment oftype 2 diabetes mellitus in China. At present, the pharmacokinetics of baicalin in type 2 diabeticrats following oral administration of Radix scutellariae extract was investigated. The resultsshowed that the pharmacokinetics (especially AUC) of baicalin in type 2 diabetic rats after oraladministration of Radix scutellariae extract was remarkably different from that in normal rats.Then the mechanism which resulted in the increased AUC of baicalin in diabetic rats wasinvestigated from system clearance and presystemic metabolism. And it was found that theincreased AUC of baicalin in diabetic rats at least partly resulted from higher production ofbaicalein in the intestinal tract of type 2 diabetic rats.Moreover, the activity of ß-glucuronidase inintestinal mucosa of type 2 diabetic rats was demonstrated to be higher than that in normal rats,which confirmed the results above. In conclusion, the pharmacokinetic behavior of baicalin wassignificantly altered in type 2 diabetic rats after orally administrated Radix scutellariae extract,which may partly result from the increased activity of intestinal ß-glucuronidase under thepathological state of type 2 diabetes mellitus.