AIM: We have previously proved that oxidized low-density lipoprotein (oxLDL), a proatherogenic lipoprotein, plays a pivotal role in the development of atherosclerotic calcification (AC). The present study was performed to investigate whether tanshinone II A (TS II A), an anti-oxidant which has been shown to inhibit in vitro oxidation of LDL, has the effects to inhibit AC in rat model and by which, if any, mechanisms. METHODS: Rat AC model was induced by excessive vitamin D(2) (VD) and high cholesterol diet (HCD), which was proven to be successful histopathologically and biochemically. RESULTS: Administration of AC rats with TS II A (35, 70 mg/kg) dose-dependently attenuated the AC pathological changes, meanwhile reduced the vessel contents of lipid and calcium. However, TS II A had no effects on serum levels of lipids, calcium and 25-OH VD. Further studies revealed that TS II A decreased serum concentration of oxLDL, reduced the superoxide anion production and malondialdehyde (MDA) in vessel. In addition, TS II A increased vessel Cu/Zn SOD activity, upregulated vessel mRNA and protein expression of Cu/Zn SOD. CONCLUSION: The results suggested that TS II A significantly attenuated the AC in rat model, which might be attributed to its inhibition of oxLDL production independent of the serum levels of lipids, calcium and 25-OH VD, and that increasing of Cu/Zn SOD activity as well as mRNA and protein expression by TS II A might protect LDL against oxidation induced by superoxide anion in vessel.
AIM: We have previously proved that oxidized low-density lipoprotein (oxLDL), a proatherogenic lipoprotein, plays a pivotal role in the development of atherosclerotic calcification (AC). The present study was performed to investigate whether tanshinone II A (TS II A), an anti-oxidant which has been shown to inhibit in vitro oxidation of LDL, has the effects to inhibit AC in rat model and by which, if any, mechanisms. METHODS:Rat AC model was induced by excessive vitamin D(2) (VD) and high cholesterol diet (HCD), which was proven to be successful histopathologically and biochemically. RESULTS: Administration of AC rats with TS II A (35, 70 mg/kg) dose-dependently attenuated the AC pathological changes, meanwhile reduced the vessel contents of lipid and calcium. However, TS II A had no effects on serum levels of lipids, calcium and 25-OH VD. Further studies revealed that TS II A decreased serum concentration of oxLDL, reduced the superoxide anion production and malondialdehyde (MDA) in vessel. In addition, TS II A increased vessel Cu/Zn SOD activity, upregulated vessel mRNA and protein expression of Cu/Zn SOD. CONCLUSION: The results suggested that TS II A significantly attenuated the AC in rat model, which might be attributed to its inhibition of oxLDL production independent of the serum levels of lipids, calcium and 25-OH VD, and that increasing of Cu/Zn SOD activity as well as mRNA and protein expression by TS II A might protect LDL against oxidation induced by superoxide anion in vessel.
Authors: Dongxing Zhu; Neil C W Mackenzie; Colin Farquharson; Vicky E Macrae Journal: Front Endocrinol (Lausanne) Date: 2012-08-06 Impact factor: 5.555