RESUMO
AIMS: Platelet-derived growth factor (PDGF) promotes liver collagen deposition, acting on hepatic stellate cells. Despite this, low serum PDGF levels were reported in chronic hepatitis C or B infection, although some studies yield the opposite result. Since PDGF may be related not only to fibrosis but also with vascular, neuronal or muscle disease, it is important to analyze its behavior in alcoholics. METHODS: In total, 17 controls and 62 alcoholic patients consecutively admitted to the hospitalization unit of the Internal Medicine Service were included. We determined serum levels of PDGF C, routine laboratory evaluation, tumor necrosis factor-α, interleukin (IL)-6 and IL-8 and malondialdehyde (MDA) levels. We analyzed the relationships between PDGF and liver function, ethanol intake and inflammatory reaction by both univariate and multivariate analysis to discern which variables PDGF levels depend on. RESULTS: Serum PDGF levels were significantly lower among patients (675 ± 466 pg/ml) than among controls (1074 ± 337 pg/ml; Z = 3.70; P < 0.001), and even lower among cirrhotics (549 ± 412 among cirrhotics vs 778 ± 487 among non-cirrhotics; Z = 2.33; P = 0.02). PDGF levels showed a direct correlation with prothrombin activity (ρ = 0.50; P < 0.001), platelet count (ρ = 0.44; P < 0.001) and inverse ones with bilirubin (ρ = -0.39; P = 0.002), IL-6 (ρ = -0.33; P = 0.016), IL-8 (ρ = -0.47; P < 0.001), and MDA levels (ρ = -0.44; P < 0.001). By multivariate analysis, only prothrombin activity and platelet count were independently related to PDGF. CONCLUSION: PDGF-C levels are decreased in alcoholics, especially among cirrhotics. Multivariate analysis discloses that only prothrombin activity and platelet count are independently related to PDGF-C levels.
