Metformin Effect on Endocan Biogenesis in Human Endothelial Cells Under Diabetic Condition.

BACKGROUND AND AIM: Endocan is a novel endothelium-derived proteoglycan and may play a role in endothelial cells activity under diabetic conditions. Here, we evaluated the effect of high glucose concentration (30 mmol glucose) on endocan level in presence or absence of metformin in human umbilical vein endothelial cells (HUVECs). METHODS: Cells were incubated with 30 mmol glucose for 72 h. High glucose content, metformin (2.5 to 500 mmol) and compound C (10 mmol) effects were assessed on cell viability. HUVECs migration was studied by scratch test. The changes in endocan expression and protein level were evaluated by RT-PCR, ELISA and flow cytometry assays. Griess reaction was used to measure NO levels. Functional activity of endothelial cells was monitored related to lipoprotein lipase activity using Dil-Ac-LDL uptake. p-AMPK/AMPK ratio was assessed by western blotting. RESULTS: Cells viability significantly was reduced under high glucose condition (p <0.05). 30 mmol glucose inhibited HUVECs migration, whereas these features were improved by 50 mmol metformin (p <0.05). Endocan transcription and protein levels were increased in diabetic HUVECs exposed to metformin (p <0.05). Metformin increased NO production in HUVECs under high glucose condition (p <0.001). Metformin increased LDL uptake capacity under high glucose condition (p <0.05). The addition of compound C blunted these effects. Western blot analysis confirmed the increase of p-AMPK/AMPK ratio in metformin-treated cells. CONCLUSION: Data demonstrated that metformin could promote angiogenic potential of endothelial cells which its reduction is a main cause in the development of diabetic foot ulcer, probably by the regulation of endocan dynamics under high glucose condition.

Evaluation of Various Biological Activities of the Aerial Parts of Scrophularia frigida Growing in Iran.

The current study was assigned to evaluate the total phenol, total flavonoid content (TPC, TFC) and antioxidant properties of extracts from the aerial parts of Scrophularia frigida (S. frigida). Extracts were also tested by preliminary phytochemical screening as well as cytotoxic activity against Artemia salina, MCF-7 (human breast carcinoma) and SW-480 (colon carcinoma) and L-929 (normal) cell lines along with antimicrobial characteristic. DPPH, MTT and Brine shrimp lethality tests and disc diffusion method were carried out to determine the biological activities of the different extracts of S. frigida. In addition, the extracts which had more potent antioxidant and antiproliferative activity were further analyzed by NMR and GC-MS. 40% methanol-water (from MeOH extract) fraction showed higher amounts of TPC, TFC and antioxidant property. Findings of the study for general toxicity effect showed that dichloromethane (DCM) and MeOH extracts had weak to moderate effects. Furthermore, DCM extract indicated the most potent anti-proliferative activity against cancer cell lines. No evidence of antibacterial activity was determined. On the other hand, analysis of the potent extract DCM in cytotoxic assay showed the presence of trans-phytol and cis-oleic acid in GC-MS. Furthermore, NMR analysis of potent methanolic fractions in antioxidant tests revealed the presence of iridoids and phenolics. Generally, the results of TPC, TFC and antioxidant activity of extracts and fractions were in agreement with each other.