| Objective: Hyperhomocysteinemia(hHcy)which is more often in patients with hypertension in Chinese not only promotes the progress of hypertension,also acts as a significant risk factor in the atherosclerotic disease.While how homocysteine(Hcy)impacts cardiac structure and function accompanied by hypertension still not be illuminated well.Emerging evidence suggests that immune inflammatory response participates in the pathological process of hypertension and target organ damage(TOD),T helper cell 17(Th17)and Regulatory T cell(Treg)are the most studied immune cells associated with cardiovascular disease,disorders of immune inflammation caused by imbalance of Th17 / Treg are involved in the hypertension and TOD.Differentiation of Th17 and Tregs are modulated by a characteristic transcription factor respectively,and the activation of transcription factor is closely related with the methylation status of its promoter,while methyl is prodyced by the methionine cycle in whichHcy,the product of methionine metabolism,accepts a methyl from N5-methyl 4 hydrogen folic acid and regenerate methionine.It is very important of methionine cycle in providing methyl for widespread methylation in the body.Whether the reduce of gene expression affected by demethylation in the condition of Hcy metabolic blocked may impact the differentiation of Th17 and Treg literature have not been reported.This study aims to explore the correlation of Hcy and hypertrophy of left ventricle in older elderly hypertensive patients.For a further study,spontaneously hypertensive rats(SHR)were selected as the object which were fed with methionine for a hHcy model,analyse the effects of highHcy on cardiac damage,the balance of Th17 / Treg and on the methylation of associated gene transcription factor.methods:(1)sequential recruit 378 cases of elderly inpatients aged 80-years old or more who were diagnosed with primary hypertension among January 2012 to January 2015 in our department.All cases were divided into non H-type hypertension group with 142 patients and H-type hypertension group with 236 patients according to the level of Hcy.Height,weight,medicines applied and blood pressure,the concentration of plasma Hcy were recorded.Color Doppler ultrasonic equipment was used to determine the morphology and structure of left ventricle.The relationship of plasma Hcy and remodeling of left ventricle was analyzed.(2)seven-week-old SHR fed with perfect compound diet or appended methionine compound diet were divided into three groups after a period of one week adaptive feed.Control group were fed with perfect compound diet without methionine,methionine group were fed with perfect compound diet added 2% methionine,treatment group were fed as methionine group in the first 8 weeks,and then as the fodder of control group,but added with vitamin B12 0.09 mg/(kg.d)and folate 4mg/(kg.d).The weight,plasma Hcy levels and blood pressure were measured every four weeks,cardiac structure and function were detected using echocardiography,the count of Th17 and Treg cells in peripheral blood was analyzed by flow cytometry,plasma inflammation factors were detected and heart tissue based on histopathology and molecular biological method were inspected at eighth week,twelfth week,sixteenth week and twentieth week,respectively,and invasive hemodynamic method to check the cardiac function before killed.Results:(1)The ratio of left ventricular hypertrophy was higher in H-type hypertension group than that in non H-type hypertension group.Patients in H-type hypertension group had higher systolic blood pressure,higher plasma level of Hcy and higher levels of 1eft ventricular posterior wall thickness(LVPWT),Left ventricular ejection fractions(LVEF),higher interventricular septal thickness(IVST)and higher left ventricular mass index(LVMI)compared to non H-type hypertension group.There was positive correlation between LVMI and Hcy,multivariable logistic regression analysis showed that hyperhomocysteinemia was an independent risk factor of LVMI.(2)Plasma level of Hcy and systolic blood pressure,higher than that of control group,were the same as each other between methionine group and treatment group during the first 8 weeks.Methionine group manifested a continue increasing concentration of plasma Hcy,while the systolic blood pressure raised to the peak at 12 th week and then decreased rapidly,Hcy level in treatment group dropped rapidly after 8 weeks and reached to a similar level as the control at 16 th week,blood pressure in treatment group experienced a modest rise and began to decrease at 12 th week.Compared to control group and treatment group,rats in methionine group who appeared the earliest increace of Left ventricular end-diastolic dimension(LVEDD)displayed significantly lower diastolic function at 20 th weekend and the systolic function was significantly reduced since16 th week to the 20 th weekend.Count of Th17 cells in peripheral blood were similar between methionine group and treatment group,which were higher than that of control group.There was a rising trend of Th17 content in methionine group from12 th week to 16 th week and at 20 th weekend there was no difference in the three groups of Th17.Count of Treg in peripheral blood in the treatment group,higher than control group at every point,were the highest in each point of the experiment,and also higher than that of methionine group at 12 th week,16 th week and 20 th week,respectively.At 8th week it was higher of interleukin-17(IL-17),interleukin-6(IL-6)concentration in peripheral blood and IL-17 m RNA,orphan nuclear receptor gamma t(ROR?t)m RNA in myocardium in methionine group and treatment group than control group.The above indexes remained higher in methionine group than both of treatment group and control group at 12 th week,treatment group had fallen to similar with the control group,the same tendency of above indexes maintained to 16 th week,and the level of IL-6 in the treatment group dropped to lower than the level of control group.There was no significance difference of plasma IL-17,IL-6 and myocardium ROR?t m RNA between three groups at 20 th week,only IL-17 m RNA in myocardium of methionine group was higher than treatment group and control group.At 8th week it was significantly higher of transforming growth factor-?(TGF-?,interleukin-10(IL-10)concentration in peripheral blood and IL-10 m RNA,forkhead box protein 3(Fox P3)m RNA in myocardium in methionine group and treatment group than control group.From the9 th week the above inflammation factors in treatment group increased rapidly and exceeded methionine group,and at 16 th week these indexes were higher in treatment group than both of methionine group and control group which two groups were similar,and remained the tendency to the end of experiment.Using western blot to detect the protein of ROR?t and Fox P3 in the myocardial of rats in each group,results showed that protein of ROR?t and Fox P3 in methionine group and treatment group were significantly higher than that of control group,protein of ROR?t in treatment group decreased but there was no statistical differences compared with control group,which two groups were lower than that of methionine group.Fox P3 protein in methionine group was lower than the treatment group but higher than the control group at 12 th and 16 th week,the difference reached a statistical significance.Further to analyze the related gene methylation levels of Th17 and Treg cells,the results showed that IL-17 and ROR?t gene promoter methylation in methionine group was low and in the treatment group was high,reversely of IL-10 and Fox P3 gene promoter methylation.Histopathological staining showed that methionine group and treatment group had higher ratio of perivascular collagen area to lumen area(PVCA/LA)and higher collagen volume fraction(CVF)than the control group,and the tendency kept to the 20 th weekend in methionine group,PVCA/LA in the treatment group gradually declined after 8th week and lower than the methionine but slightly higher than the control group at 16 th week,at 20 th week it reducd to close to the control level.CVF,which was lower in treatment group than the methionine group and slightly higher than the control group at 12 th week,and similar to the control group at 16 th and 20 th week,improved faster than PVCA/LA in the treatment group.Conclusion: hHcy may be an independent risk factors of hypertensive left ventricular hypertrophy.High level of Hcy accelerated systolic and diastolic dysfunction through accumulation of fibrosis in myocardium and perivascular wall which led to adverse cardiac remolding,folic and vitamin B12 had a protective effect on heart function by reversing the adverse changes by Hcy.High level of Hcy may lead to unbalance of Th17/Treg,of which the correlated immune inflammation may be a new approach associated with hypertensive heart damage by high level of Hcy. |
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