Immunopotentiotor Effect of α-Tocopherol on Cytokine Expression in the Lymphocytes in the Elderly People

Aging is associated with attenuation of immune responses. Studies show that old people are vulnerable to infectious diseases such as influenza. α-Tocopherol as an immunomodulator affects immune responses. In the present study, the effect of α-tocopherol, on lymphocyte responses i.e. interferon-gamma (IFN-γ), Tumor Necrosis Factor-alpha (TNF-α), and nuclear factor-κB (NF-κB)  in elderly individuals was evaluated. Heparinized blood samples were prepared from 10 elderly individuals (n=10, age >80 years) as the experimental group and 10 young individuals (n= 10, 20-40 years) as the control group. The separated Peripheral Blood Mononuclear Cells (PBMCs) of aged and young individuals were used for treatment with 2 μg/mL of α-tocopherol and 2 μg/mL of Purified Protein Derivative (PPD) after 12 and 24 h incubation period. After isolation of total RNA and synthesize of cDNA, the gene expressions of IFN-γ, TNF-α, and NF-κB were evaluated by real-time PCR method. β-Actin gene was considered as the internal control gene. Results showed that treatment with α-tocopherol increased the IFN-γ expression in old and young lymphocyte groups. The mRNA level of NF-κB increased in the PPD group after 12 h in both old and young groups (p <0.05). There were no alterations in TNF-α expression in both groups. It seems that α-tocopherol is effective in the promotion of cytokine responses in old individuals and may be useful as a supplement for improving the immune system of elderly people.