Objective To study the effect and molecular mechanism of vitamin D(VitD)on Tfh cells of MRL/lpr lupus mice.Methods C57/B6 mice and MRL/lpr lupus mice were transfected with siRNA to construct VDR knockout mouse models.Splenic Tfh cells of C57/B6 mice and MRL/lpr lupus mice were divided into control group,lupus group and VDRsiRNA lupus group(treated with vitamin D 0,1 and 10 nmol·L-1,respectively)by siRNA transfection.The percentage of Tfh cells was detected by flow cytometry.MRL/lpr lupus mice Peyer node Tfh cells were randomly divided into 7 groups,blank control group,vitamin D dose groups of 1 and 10 nmol·L-1,paricalcitol group(VitD 10 nmol·L-1+PA),VDRsiRNA control group,VDRsiRNA group(VitD 10 nmol·L-1),CaN inhibitor group(VitD 10 nmol·L-1+CsA),and incubated for 72 h.The concentration of calcium ions in Tfh of each group was detected.The expressions of AT1R,NFAT,CaN and P-CaN in Tfh cells were determined by Western blotting.Results The percentage of Tfh cells decreased significantly with the increase of vitamin D dose.Vitamin D CaN reduce the intracellular calcium concentration of Tfh,up-regulate the expression of AT1 protein in Tfh cells,and down-regulate the expression of CAN,P-CaN and NFAT protein in a dose-dependent manner,and the effect is more obvious when combined with PA.Conclusion Vitamin D may regulate the activation of follicular T helper cells in MRL/lpr mice via the Ca-CaN-NFAT pathway.

Objective To study the effect and molecular mechanism of vitamin D(VitD)on Tfh cells of MRL/lpr lupus mice.Methods C57/B6 mice and MRL/lpr lupus mice were transfected with siRNA to construct VDR knockout mouse models.Splenic Tfh cells of C57/B6 mice and MRL/lpr lupus mice were divided into control group,lupus group and VDRsiRNA lupus group(treated with vitamin D 0,1 and 10 nmol·L-1,respectively)by siRNA transfection.The percentage of Tfh cells was detected by flow cytometry.MRL/lpr lupus mice Peyer node Tfh cells were randomly divided into 7 groups,blank control group,vitamin D dose groups of 1 and 10 nmol·L-1,paricalcitol group(VitD 10 nmol·L-1+PA),VDRsiRNA control group,VDRsiRNA group(VitD 10 nmol·L-1),CaN inhibitor group(VitD 10 nmol·L-1+CsA),and incubated for 72 h.The concentration of calcium ions in Tfh of each group was detected.The expressions of AT1R,NFAT,CaN and P-CaN in Tfh cells were determined by Western blotting.Results The percentage of Tfh cells decreased significantly with the increase of vitamin D dose.Vitamin D CaN reduce the intracellular calcium concentration of Tfh,up-regulate the expression of AT1 protein in Tfh cells,and down-regulate the expression of CAN,P-CaN and NFAT protein in a dose-dependent manner,and the effect is more obvious when combined with PA.Conclusion Vitamin D may regulate the activation of follicular T helper cells in MRL/lpr mice via the Ca-CaN-NFAT pathway.

Objective To establish a RP-HPLC method for the determination of psoralen and isopsoralen in Qianggu Capsules.Methods An Agilent C18(4.6 mm?250 mm,5 ?m)column was used.The methyl-water(45:55) was used as the mobile phase.The flow rate was 1.0 mL?min-1.The determination wavelength was at 246 nm.Results The linear range was 0.08～0.80 ?g,for psoralen,r=0.999 8,the average recovery rate was 99.3 %,RSD=1.4 %(n=5),and for isopsoralen,r=0.999 9,the average recovery rate was 98.5 %,RSD=0.8 %(n=5).The linear equation was Y=7 365.9X-102.7 for psoralen and Y=7 556.0X-65.3 for isopsoralen.Conclusion The method is simple,reliable,accurate,and can be applied to control the quality of Qianggu Capsules.