title: Tobacco smoking decreases plasma concentration of the emerging cardiovascular risk marker, L-homoarginine.
abstract: BACKGROUND
  Tobacco smoking is one of the most important risk factors for cardiovascular disease (CVD) and few biomarkers have been linked to the increased risk of CVD and tobacco smoking. Tobacco smoke has been shown to elevate the plasma levels of asymmetric dimethylarginine (ADMA), a metabolite of L-arginine and an endogenous inhibitor of endothelial nitric oxide synthase. The other potential biomarker that has not been studied to date is L-homoarginine, a homolog of L-arginine. The aim of this study was to evaluate the effects of cigarette smoking on L-homoarginine and other CVD biomarkers.
  
  
  RESULTS
  In a cross-sectional study of 231 healthy male volunteers, we measured plasma levels of L-homoarginine, L-arginine, and ADMA using the HPLC method. In smokers, we found that plasma L-homoarginine levels were 16.7% lower compared with nonsmokers after adjusting for age, body mass index, plasma creatinine, and metal blood levels (P<0.05). Plasma ADMA levels were only 6.0% higher in smokers when compared with the levels found in nonsmokers (P>0.05).
  
  
  CONCLUSIONS
  Our results suggest that, in contrast to ADMA, there is a strong association between exposure to tobacco smoke and plasma L-homoarginine levels. Further research in this field is needed to explain the mechanisms of the relationship of low L-homoarginine levels, smoking, and cardiovascular health.
authors.affiliation: Department of Chemical Hazards and Genetic Toxicology, Institute of Occupational Medicine and Environmental Health.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Sobczak
authors.forename: Adam
authors.initials: A
authors.lastname: Prokopowicz
authors.forename: Malgorzata
authors.initials: M
authors.lastname: Radek
authors.forename: Magdalena
authors.initials: M
authors.lastname: Szula
authors.forename: Marzena
authors.initials: M
authors.lastname: Zaciera
authors.forename: Jolanta
authors.initials: J
authors.lastname: Kurek
authors.forename: Maciej Lukasz
authors.initials: ML
authors.lastname: Goniewicz
mesh_terms: D000328:Adult; D015415:Biomarkers; D002318:Cardiovascular Diseases / Q000097:blood* / Q000209:etiology*; D003404:Creatinine / Q000097:blood; D003430:Cross-Sectional Studies; D005260:Female; D049690:History, Ancient; D006709:Homoarginine / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects* / Q000097:blood*
chemical_list: D015415:Biomarkers; D006709:Homoarginine; D003404:Creatinine