ABSTRACT
AIMS: To investigate the association of IL10 SNPs in chronic hepatitis C (CHC) patients with and without the first major depressive episode (MDE), as well as their association with plasma levels of target cytokines. METHODS: A hundred and thirty two CHC patients (32 with and 100 without first MDE) and 98 controls were prospectively enrolled in this cross-sectional study. MDE was diagnosed by a psychiatrist, using the Mini International Neuropsychiatric Interview Plus 5.0. IL10 polymorphisms (-1082 G/A, -819C/T and -592C/A IL10 SNPs) were evaluated by Taqman SNP genotyping assay. Plasma concentrations of IL-2, IL-6, IL-10, IFN-γ and TNF-α were determined using the Human Th1/Th2 Cytometric Bead Array kit. The associations were investigated by logistic models. RESULTS: The frequencies of the studied IL10 SNPs did not differ between the CHC patients and controls. The first MDE was positive and independently associated with the IL10-1082*A, IL10-819*T and IL10-592*A (ATA) low producer haplotype (OR = 1.50; 95% CI = 1.11-2.04; P = 0.009) and current alcohol misuse (OR = 4.29; 95% CI = 1.22-15.05; P = 0.02), and inversely associated with increasing age (OR = 0.94; 95% CI = 0.91-0.98; P = 0.006). In addition, plasma level of TNF-α was significantly higher in the carriers than in the non-carriers of the IL10 ATA haplotype in patients with the first MDE. The IL-10 and IL-2 plasma levels were significantly higher in the carriers than in non-carriers of the IL10 GCC high producer haplotype, demonstrating the functionality of the studied IL10 polymorphisms. CONCLUSIONS: This is the first study to demonstrate that the IL10 low producer ATA haplotype is associated with the first MDE in patients with CHC.
