Abstract:AimTo explore the effect of Vitamin K2 on vascular calcifiction in old ovariectomized rats model.MethodsThirty-six ten months female SD rats were allocated into three groups randomly: sham operation group, ovariectomized (OVX) group and OVX＋Vitamin K2 (OVX＋VK2) group.Rats in OVX＋VK2 group were administered orally with Vitamin K2 (30 mg(kg·d), 5 times a week) after three weeks of ovariectomy for 12 weeks.The urine and serum of all rats were kept every three weeks.All rats were sacrificed after 18 weeks, uterus and arteries were observed by histochemical method.The contents of MGP in serum and urine were determined by enzyme-linked immunosorbent assay (ELISA).Relative quantification of MGP mRNA expression in arterial was detected by Fluorescent real-time quantitative reverse-transcription polymerase chain reaction.Expression of ucMGP was detected by immunochistochemistry.Aterial calcification was evaluated by Von Kossa staining.The content of arterial calcium was measured.ResultsAfter 18 weeks of ovariectomized, the pathological section of uterus and aortic had differernt variation in different groups.The content of estrogen in serum had no difference before ovariectomized.Before sacrifice, the content of estrogen of sham group had no change, the other groups reduced (p<0.05).The content of MGP in serum and urine had no difference before ovariectomized, the content of MGP in serum and urine decreased in OVX group, the content of MGP in serum and urine decreased and then increased in OVX＋VK2 group.Relative quantification of MGP mRNA expression of aterial in OVX＋VK2 group was significantly lower than sham group (p<0.01), and was higher than that in OVX group (p<0.01).

Abstract:Aim To investigate the effects of rosiglitazone on insulin resistance and the expression of adiponectin and its receptors in the adipose tissue in ovariectomized rats. Methods Thirty-six female Sprague-Dawley rats were randomly divided into three groups: the sham control group,the ovariectomized group and the ovariectomized+rosiglitazone group.The changes of insulin sensitive index(ISI),blood pressure were measured. The content of visceral adipose depots was observed.The expression of adiponectin and its receptors(AdipoR1 and AdipoR2) in the visceral adipose tissue were analyzed by reverse transcription polymerase chain reaction(RT-PCR). Results Compared with the sham control group,the blood pressure and the content of visceral adipose depots were significantly increased,ISI was significantly decreased,and the expressions of adiponectin and AdipoR1/R2 in visceral adipose were significantly decreased in the ovariectomized rats.Compared with the ovariectomized group,these effects were reversed by rosiglitazone in the ovariectomized+rosiglitazone group. Conclusion Rosiglitazone improved insulin resistance by up-regulating the expression of adiponectin and its receptors in the adipose tissue in ovariectomized rats.

Abstract:Aim To investigate the effects of early estrogen replacement therapy(ERT)of different doses on atherosclerotic lesions,serum lipid and monocyte chemoattractant protein-1(MCP-1)levels in ovariectomized fat-fed female rabbits.Methods Twenty-eight female New Zealand White rabbits were randomly divided into sham operation group,ovariectomized group,ovariectomized with low-dose ERT group(estradiol benzoate 200 μg)and ovariectomized with high-dose ERT(estradiol benzoate 1 mg)group.All rabbits were given high-fat diets after the surgery for 12 weeks.The levels of serum total cholesterol(TC),low density lipoprotein cholesterol(LDLC),high density lipoprotein cholesterol(HDLC),estradiol and MCP-1 were measured.12 weeks later,the aortas were taken for pathological analysis and for calculating the areas of atherosclerotic plaques.Results Compared with sham operation group,the serums levels of TC,LDLC and MCP-1 in ovariectomized group were significantly increased after high-fat diet for 12 weeks,meanwhile the serum levels of HDLC and estradiol were decreased.But the above indexs had no differences between ERT groups and sham operation group.Compared with low-dose ERT group,high-dose ERT group had higher levels of estradiol and lower levels of MCP-1.After high-fat diet for 12 weeks,the extent of atherosclerotic lesions of aorta in ovariectomized group was remarkably bigger than that in sham operation group.The extent in both ERT groups was significantly smaller than that in sham operation group and ovariectomized group.There were no statistical difference in the aortic lesions among two ERT groups.The areas of atherosclerotic plaque were positively correlated with the serum levels of LDLC,TC,and MCP-1,but negatively correlated with the serum levels of HDLC and estradiol.Conclusions Early ERT can modulate the blood lipid,decrease the serum levels of MCP-1 and reduce the areas of atherosclerotic plaque.The antiatherogenic effect of early ERT may be associated with its effects of ameliorating the lipid metabolism and anti-inflammation.

Abstract:Aim To investigate the inhibiting effect of 17-β estradiol on insulin resistance induced by the high fructose diet in ovariectomized rats. Methods Thirty six ovariectomized female Sprague-Dawley(S-D)rats were fed with the high fructose diet for eight weeks to induce insulin resistance. Then they were randomly divided into three groups: the model group, the 17-β estradiol replacement group,the vehicle control group.The normal control group twelve rats were fed with the normal diet for eight weeks.Body weight(BW),systolic blood pressure(SBP),glucose tolerance,plasma triglyceride(TG),total cholesterol(TC),high density lipoprotein cholesterol(HDLC)and low density lipoprotein cholesterol(LDLC),fasting blood sugar(FBS)and fasting serum insulin(FSI)and insulin sensitivity index(ISI)were measured. Results Compared with the normal control group,BW(p<0.05),SBP(p<0.05), the levels of plasma TG,TC,LDLC,FBS(all p<0.05) and FSI(p<0.01) were increased significantly and the plasma HDLC level was decreased significantly (p<0.05) in the model group. Glucose tolerance was decreased significantly(p<0.05)and injury of pancreatic β-cell was observed in the model group.ISI was decreased significantly(p<0.05) and insulin resistance was arisesed in the model group.Compared with the model group,these effects were reversed, ISI was increased significantly(p<0.05) and insulin resistance was inhibited in the 17-β estradiol replacement group. Conclusion 17-β estradiol inhibited insulin resistance,injury of pancreatic β-cell and lipid dysbolism induced by the high fructose diet in ovariectomized rats.These findings suggested that estradiol in female rat might provide protection againt the effect of the high fructose diet,which caused hypertension,insulin resistance,injury of pancreatic β-cell and lipid dysbolism.