ABSTRACT
The different extracts and of Viola yedoensis Makino and Viola inconspicua were analyzed and identi-fied by Fourier transform infrared spectroscopy (FT-IR). One-dimensional infrared spectrum showed that the extracts of Viola yedoensis Makino and Viola inconspicua contained the aromatics,volatile substances and glyco-sides,with not significant differences from each other. However,different extraction sites of the two medicinal materials in second derivation spectrum were obviously different,especially the number of automatic peaks and peak intensity in the range of 970 800 cm-1. Viola yedoensis Makino displayed 5 automatic peaks,6 automatic peaks and 6 automatic peaks,while Viola inconspicua displayed 7 automatic peaks,4 peaks,4 peaks in the second derivation spectrum of petroleum ether extraction site,chloroform extraction site and the ethyl acetate extraction site. In addition,the peak position of the strongest peak in the second derivative of the ethyl acetate extraction site was 1 467 cm-1,while the strongest peak of the Viola inconspicua was at 1 384 cm-1,so the two medicinal mate-rials can be distinguished by the strongest peak position of ethyl acetate extraction site in second derivation spec-trum. Studies demonstrated that one-dimensional infrared spectroscopy combined with the second-order derivative analysis could achieve the accurate identification between Viola yedoensis Makino and Viola inconspicua. This research provides new ideas and new methods for the identification of Viola and other adulterants.
ABSTRACT
Objective To observe the effect of exogenous insulin on the expression of P-glycoprotein (P-gp)and the secretion of insulin in pancreatic beta cells (INS-1 832/13).Methods Insulinoma cells (INS-1 832/13) were cultured with 0.5 μmol/L exogenous insulin for 30 days.MTT assay was used to measure cell viability.Quantitative RT-PCR and western blot were used to detect the expression of P-gp mRNA and protein respectively,and glucose stimulated insulin secretion (GSIS) were measured by radioimmunoassay.Results Compared with control group,0.5 μmol/L exogenous insulin promoted the viability of INS-1 832/13 cells [(102.00±12.99) vs (356.00±35.51),P<0.05] and accelerated P-gp expression [(107.50±17.08) vs (307.50±44.25)] both at mRNA and protein levels [(105.00±12.91) vs (192.50±35.94),P<0.05].Glucose stimulated insulin secretion was positively correlated with P-gp expression level,but had no significant effect on basal insulin secretion.Conclusion Exogenous insulin can promote the secretion function of INS-1 832/13 cells,and the mechanism may be related to the expression of P-gp.
ABSTRACT
Objective To analyse the effects of high insulin on the expression and function of P-glycoprotein (P-gp), and preliminarily investigate the influence of insulin on chemotherapeutic sensitivity in MCF-7/ADR cells. Methods MCF-7/ADR cells were cultured with different concentrations of insulin(0.001, 0.005, 0.01, 0.05 and 0.1μmol/L). Real-time PCR was used to detect the expression of P-gp mRNA. Western blot assay was used to detect the expression level of P-gp. Rhodamine 123 was used to detect the efflux function level of P-gp. Cell viability and chemotherapeutic sensitivity were detected by MTT assay. Results High concentration of insulin (0.1 μmol/L) promoted the proliferation of MCF-7/ADR cells. The concentration of insulin (0.05 and 0.1 μmol/L) accelerated P-gp mRNA and protein expression, which also augmented the efflux function of P-glycoprotein and reduced the chemotherapeutic sensitivity to epirubicin. Conclusion High concentration of insulin may influence the drug resistance of breast cancer cells by promoting the expression and function of P-glycoprotein of MCF-7/ADR cells.