Effect of Capsaicin on Proliferation and Migration of Vascular Smooth Muscle Cells in Spontaneously Hypertensive Rats

OBJECTIVE To investigate the effect of capsaicin on proliferation and migration of vascular smooth muscle cells(VSMCs) in spontaneously hypertensive rats. METHODS After construction of spontaneously hypertensive rats vascular smooth muscle cells in vitro, cells were treated with 20 μmol·L^-1 capsaicin(high dose group), 10 μmol·L^-1 capsaicin(middle dose group), 5 μmol·L^-1 capsaicin(low dose group), or 1 μmol·L^-1 irbesartan(irbesartan group) directly or treated with 20 μmol·L^-1 capsaicin(high dose group), 10 μmol·L^-1 capsaicin(middle dose group), 5 μmol·L^-1 capsaicin(low dose group), or 1 μmol·L^-1 irbesartan(irbesartan group) after specifically inhibiting the expression of CD36, the proliferation of VSMCs was detected by MTT method, the migration of VSMCs was detected by Boyden chemotaxis, and the changes of smooth muscle 22a (SM22a) and Calopnin mRNA and protein expression levels were detected by qRT-PCR and Western blotting. RESULTS After VSMCs were treated with capsaicin or irbesartan respectively, compared with the control group, the cell proliferation rate and migration rate in the high, middle, low dose of capsaicin group or irbesartan group reduced, SM22a and Calponin expression were up-regulated. Compared with the irbesartan group, SM22a and Calponine expression in the high dose of capsaicin group was up-regulated, while that in the middle or low dose of capsaicin group were down-regulated. After inhibiting CD36 expression specifically, compared with the control group, the cell proliferation rate in high, middle, low dose of capsaicin group or irbesartan group reduced, the migration rate was further reduced, and SM22a or Calponin expression were up-regulated. Compared with the irbesartan group, the SM22a expression in the high, middle, low dose of capsaicin group was up-regulated, while Calponin expression in the high, middle, low dose of capsaicin group were down-regulated. CONCLUSION High, middle, low dose of capsaicin can up-regulate SM22a and Calponin expression, inhibit the expression of CD36 to promote VSMCs in spontaneously hypertensive rats transform from undifferentiated phenotype to differentiation phenotype, thereby inhibiting proliferation and migration of VSMCs and vascular remodeling in hypertension, promoting restoration of arterial wall normal physiological function and to reduce blood pressure.