Determination Of Serum Magnesium, Zinc, Copper In Different States Of Glucose Regulation

Objective:Insulin resistance and dysfunctional insulin secretion are the two main parts of pathophysiological mechanism of type 2 diabetes mellitus. It can also cause the metabolic disorder of serum trace elements in addition to the apparent glucose metabolic disorder. Therefore,we performed this cross-sectional study to determine the serum level of magnesium,zinc and copper in different states of glucose regulation,and to evaluate the relative role of serum level of three elements with insulin resistance,glucose,blood pressure,blood lipid profile and so on.Methods:One hundred and eighty-eight subjects were enrolled in the study. A 75g oral glucose tolerance test was undertaken with fasting and 2 hour postprandial plasma glucose (2hBG) was available.The subjects were divided into three groups:normal glucose tolerance (NGT,FBG<6.1mmol/L and 2hBG<7.8mmol/L,n=78),impaired glucose tolerance (IGT,6.1mmol/L≤FPG<7.0mmol/L or 7.8mmol/L≤2hBG<11.1mmol/L,n=73),and newly diagnosed diabetic patients(NDM,FBG≥7.0mmol/L,or 2hBG≥11.1mmol/L, n=37).Body weight(BW),height(H),waist circumference(WC),systolic(SBP) and diastolic(DBP) blood pressure,body mass index(BMI) were calculated. Fasting blood samples were drawn to measure levels of triglyceride(TG), glucose,cholesterol(TC).The serum levels of magnesium,zinc and copper were determined with atomic absorption spectrophotometry.The levels of fasting insulin(FIns) and 2 hour postprandial plasma insulin(2hIns) was measured by radio immunoassay,insulin resistance index was calculated using minimal model of homeostasis(HOMA-IR).The statistic analysis was performed by SPSS11.5 software,the data of skewness distribution was changed to normal distribution by logarithm,and the data of normal distribution was described by mean±SD.A two-tailed P<0.05 was taken as statistically significant.Results:1. The levels of metabolic index SBP,FBG,2hBG and Fins were significantly different in three different glucose tolerant groups,and the SBP,FBG,2hBG levels of NDM group were higher than those of NGT group, the highest level of FIns appeared in the IGT group.2. The serum levels of magnesium,zinc,and copper in different glucose tolerant groups were:the magnesium levels in NDM group were significantly lower than NGT group(P<0.05).The zinc and copper levels were not significantly different among the three groups(P<0.05).3. The serum levels of magnesium,zinc,copper was not correlated significantly with HOMA-IR,zinc and copper were correlated with TG and Chol respectively(P<0.05).Conclusion:1. Element magnesium relates closely to DM.The diabetic serum level of magnesium is lower than the normal people.The relationship between zinc,copper and DM is not found in our study.2. Magnesium,zinc and copper are not main factors which affect insulin resistance.