title: The gonadal hormone regulates the plasma lactate levels in type 2 diabetes treated with and without metformin.
abstract: OBJECTIVE
  Our previous study showed there was a gender difference in plasma lactate concentrations in subjects with type 2 diabetes. This study investigated the effect of sex hormone levels on plasma lactic acid (LA) levels in type 2 diabetes with and without metformin therapy.
  
  
  METHODS
  Fasting whole blood specimens of 392 type 2 diabetes patients treated with metformin (n=199) or not (n=193) were collected. LA was measured with an enzyme-electrode assay. Levels of sex hormones, including testosterone (T) and estradiol (E(2)), were measured with a chemiluminescence microparticle immunoassay. Spearman's or Pearson's correlation and logistic regression analysis were performed for the factors associated with LA.
  
  
  RESULTS
  The LA level in the metformin group was significantly higher than that in the non-metformin group (1.26±0.43 vs. 1.14±0.49 mmol/L, P<0.001), and LA levels of females were significantly higher than those of males (P<0.001). LA concentrations were positively correlated with E(2) level but negatively correlated with metformin and T levels (P<0.01). The logistic regression analysis showed that gender, creatinine, E(2), metformin, and T were independent factors influencing lactate levels. Analysis of subgroups demonstrated that the LA concentrations increased with the elevation of E(2) level (P<0.05) but decreased with the rising of T level (P<0.05).
  
  
  CONCLUSIONS
  Sex hormones play an important role on regulating plasma lactate levels in diabetes patients treated with metformin. E(2) up-regulates but T tend to down-regulate lactate levels.
authors.affiliation: Soochow University, Soochow, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Shen
authors.forename: Fang
authors.initials: F
authors.lastname: Liu
authors.forename: Qing
authors.initials: Q
authors.lastname: Li
authors.forename: Junling
authors.initials: J
authors.lastname: Tang
authors.forename: Taishan
authors.initials: T
authors.lastname: Zheng
authors.forename: Fengdi
authors.initials: F
authors.lastname: Lu
authors.forename: Huijuan
authors.initials: H
authors.lastname: Lu
authors.forename: Weiping
authors.initials: W
authors.lastname: Jia
mesh_terms: D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000188:drug therapy / Q000235:genetics; D004967:Estrogens / Q000378:metabolism*; D005215:Fasting / Q000097:blood; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D019344:Lactic Acid / Q000097:blood*; D016015:Logistic Models; D008297:Male; D008687:Metformin / Q000627:therapeutic use*; D008875:Middle Aged; D012737:Sex Factors; D013739:Testosterone / Q000378:metabolism*
chemical_list: D001786:Blood Glucose; D004967:Estrogens; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D019344:Lactic Acid; D008687:Metformin; D013739:Testosterone; C517652:hemoglobin A1c protein, human