title: Clinical significance of serum complement factor 3 in patients with type 2 diabetes mellitus.
abstract: OBJECTIVE
  Although serum complement factor 3 (C3) is an acute phase reactant mainly synthesized in the liver, several recent studies have shown high C3 gene expression in adipose tissue (AT). However, the relationship between C3 and AT levels has not been fully clarified in type 2 diabetes mellitus (T2DM) patients.
  
  
  METHODS
  A total of 164 T2DM patients (109men and 55 women) participated in this cross-sectional study. A computed tomography scan was performed to measure visceral, subcutaneous, and total AT. The correlation between these factors and C3 levels was examined using Pearson's correlation analysis. A multivariate regression model was used to assess an independent determinant associated with C3 levels after adjusting the explanatory variables (i.e., all ATs [visceral, subcutaneous, and total], and clinical features [sex, age, body mass index, waist circumference, glycated hemoglobin, duration of diabetes, systolic blood pressure, diastolic blood pressure, aspartate aminotransferase levels, alanine aminotransferase levels, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, log(triglyceride levels), estimated glomerular filtration rate, and log(high-sensitivity C-reactive protein levels)]).
  
  
  RESULTS
  Serum C3 levels were correlated with visceral, subcutaneous, and total AT among both men (r=0.505, p<0.001; r=0.545, p<0.001; r=0.617, p<0.001, respectively) and women (r=0.396, p=0.003; r=0.517, p<0.001; r=0.548, p<0.001, respectively). In the multivariate regression model, the association between total AT and C3 levels remained significantly positive (β=0.490, p<0.001).
  
  
  CONCLUSIONS
  Serum C3 levels are associated with visceral, subcutaneous, and total AT in T2DM patients. Furthermore, C3 levels seem to be a marker for overall adiposity rather than regional adiposity.
authors.affiliation: Department of Diabetes and Endocrinology, Eiju General Hospital, Life Extension Research Institute, Japan. Electronic address: t-nishimura128@z6.keio.jp.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nishimura
authors.affiliation: Medical Laboratory, Eiju General Hospital, Life Extension Research Institute, Japan.
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Itoh
authors.affiliation: Department of Diabetes and Endocrinology, Eiju General Hospital, Life Extension Research Institute, Japan.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Yamashita
authors.affiliation: Diabetes Research Center, Eiju General Hospital, Life Extension Research Institute, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Koide
authors.affiliation: Medical Laboratory, Eiju General Hospital, Life Extension Research Institute, Japan.
authors.forename: Noriaki
authors.initials: N
authors.lastname: Harada
authors.affiliation: Medical Laboratory, Eiju General Hospital, Life Extension Research Institute, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Yano
authors.affiliation: Medical Laboratory, Eiju General Hospital, Life Extension Research Institute, Japan.
authors.forename: Nobuko
authors.initials: N
authors.lastname: Ikeda
authors.affiliation: Institute for Integrated Sports Medicine, Keio University School of Medicine, Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Azuma
authors.affiliation: Diabetes Research Center, Eiju General Hospital, Life Extension Research Institute, Japan.
authors.forename: Yoshihito
authors.initials: Y
authors.lastname: Atsumi
mesh_terms: D000368:Aged; D003176:Complement C3 / Q000378:metabolism*; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged
chemical_list: D003176:Complement C3
keywords: Adipose tissue; Complement factor 3; Human; Obesity; Type 2 diabetes mellitus