Association Between Serum Zinc and Copper Levels and Antioxidant Defense in Subjects Infected with Human T-lymphotropic Virus Type 1

Introduction: Copper (Cu) and zinc (Zn) are important trace elements that are also structural ions of superoxide dismutase (SOD), which reduce oxidative stress. Zinc deficiency and excess copper have been reported to be associated with inflammation. The human T-lymphotropic virus type 1 (HTLV-1) is a retrovirus, which is believed to cause systemic inflammation. The aim of this study is to measure levels of Zn, Cu, SOD, and prooxidant-antioxidant balance (PAB) in HTLV-1-positive patients and investigate the association between serum Zn and Cu concentrations and levels of oxidative stress in them.

Methods: The serum samples of 1,116 subjects who had participated in the "Mashhad Stroke and Heart Atherosclerotic Disorder" study, including 279 HTLV-1-positive and 837 HTLV-1-negative patients, were used. Levels of Zn, Cu, SOD, and PAB were measured.

Results: Zinc and SOD levels were lower in the HTLV-1-positive group; however, the difference was statistically significant only for the level of SOD (=0.003). On the other hand, levels of copper and PAB were significantly higher in HTLV-1 positive subjects; =0.004 and =0.002, respectively.

Conclusion: In HTLV-infected patients, serum Zn concentration is lower and Cu concentration is higher than healthy controls. This altered situation might be either primary or secondary to HTLV-1 infection, which should be investigated in larger studies. We showed that SOD is significantly lower in HTLV-1-infected subjects. As in some other viruses that evolve different mechanisms to potentiate virus replication by changing the physiologic condition of host cells, HTLV-1 too probably decreases the activity of copper-zinc SOD1 by suppressing its gene.