title: Complement component 3 (C3) as a biomarker for insulin resistance after bariatric surgery.
abstract: OBJECTIVE
  Since complement system has been recently associated with metabolic and cardiovascular diseases, and closely related to insulin resistance, we investigated the association of plasma complement factor 3 (C3) and factor 4 (C4) with insulin sensibility and weight loss after bariatric surgery.
  
  
  METHODS
  Serum levels of C3, C4, total cholesterol, triacylglycerol, HDL-cholesterol, LDL-cholesterol and homeostatic model assessment (HOMA-IR) measurements were assessed in morbidly obese patients before and after bariatric surgery, including a 6-month follow-up period, as well as a comparison with a lean group.
  
  
  RESULTS
  Weight loss decreased body mass index (BMI), serum triacylglycerol, and increased serum HDL-cholesterol and insulin sensitivity, as expected. C3 and C4 were significantly higher in obese individuals when compared to lean subjects (p<0.001). In addition, C3 and C4 positively correlated with BMI and HOMA-IR, however, only C3 were significantly decreased 6months after surgery.
  
  
  CONCLUSIONS
  C3 was strongly associated with insulin sensitivity after bariatric surgery.
authors.affiliation: Programa de Pós-Gaduação em Farmácia, Centro de Ciências da Saúde, Universidade Federal de Santa Catarina, Florianópolis, SC 88040900, Brazil.
authors.forename: Letícia de Oliveira Souza
authors.initials: LOS
authors.lastname: Bratti
authors.affiliation: Departamento de Análises Clínicas, Centro de Ciências da Saúde, Universidade Federal de Santa Catarina, Florianópolis, SC 88040900, Brazil.
authors.forename: Ícaro Andrade Rodrigues
authors.initials: ÍAR
authors.lastname: do Carmo
authors.affiliation: Departamento de Clínica Médica, Centro de Ciências da Saúde, Universidade Federal de Santa Catarina, Florianópolis, SC 88040900, Brazil.
authors.forename: Taís Ferreira
authors.initials: TF
authors.lastname: Vilela
authors.affiliation: Programa de Pós-Gaduação em Farmácia, Centro de Ciências da Saúde, Universidade Federal de Santa Catarina, Florianópolis, SC 88040900, Brazil.
authors.forename: Sandro
authors.initials: S
authors.lastname: Wopereis
authors.affiliation: Departamento de Análises Clínicas, Centro de Ciências da Saúde, Universidade Federal de Santa Catarina, Florianópolis, SC 88040900, Brazil.
authors.forename: Ana Carolina Rabello
authors.initials: ACR
authors.lastname: de Moraes
authors.affiliation: Departamento de Análises Clínicas, Centro de Ciências da Saúde, Universidade Federal de Santa Catarina, Florianópolis, SC 88040900, Brazil.
authors.forename: Beatriz Garcia Mendes
authors.initials: BGM
authors.lastname: Borba
authors.affiliation: Departamento de Análises Clínicas, Centro de Ciências da Saúde, Universidade Federal de Santa Catarina, Florianópolis, SC 88040900, Brazil.
authors.forename: Liliete Canes
authors.initials: LC
authors.lastname: Souza
authors.affiliation: Departamento de Análises Clínicas, Centro de Ciências da Saúde, Universidade Federal de Santa Catarina, Florianópolis, SC 88040900, Brazil. Electronic address: fabiola.monteiro@ufsc.br.
authors.forename: Fabíola Branco
authors.initials: FB
authors.lastname: Filippin-Monteiro
mesh_terms: D000328:Adult; D050110:Bariatric Surgery; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D003176:Complement C3 / Q000378:metabolism*; D003181:Complement C4 / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007333:Insulin Resistance; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000097:blood* / Q000601:surgery*; D011184:Postoperative Period
chemical_list: D015415:Biomarkers; D003176:Complement C3; D003181:Complement C4; D008055:Lipids
keywords: Bariatric surgery; C3, C4 and C3a-desArg; Complement system; Dyslipidemia and cardiovascular disease; Morbid obesity; Type 2 diabetes