Abstract 1584: Lead toxicity and oxidative stress: Possible causes of complications and grave prognosis in acute leukemic Nigeria patients
Authors: Akinloye Oluyemi , Ajadi Mary Bolanle , Adegbenro Adebayo M. , Arinola Ganiyu O. 
Published: May 2015

Toxic metals, especially implants are common causes of leukemia. Established relationship exsists between leukemia and oxidative stress. Leukemic cells produce larger amounts of reactive oxygen species (ROS). Cytokines are particulate immune proteins that serve as chemical messengers. They can have their production affected in many ways, including malignancy. Antioxidants, which control the oxidative stress state, represent a major line of physiological defense. The relationship between antioxidant status and the levels of well-known markers of oxidative stress that are measured as lipid peroxides reflects better health indices. This study, apart from investigating possible relationship between toxic metals especially Lead (Pb) in leukemic Nigeria patients, also evaluate the cytokine and antioxidant defense in this patients.

Fifty subjects including 25 acute leukemia patients and 25 apparently healthy aged matched controls were recruited for the study. Toxic trace elements (Cd, Pb, Hg, and As) were determined with AAS. The total antioxidants potential (TAP) was determined using the ferric reducing/antioxidants power (FRAP) assay and MDA was measured to evaluate the level of lipid peroxidation. Cytokines (IFN-λ, IL-4 and IgE) plasma levels were measured with ELISA. We observed significant increase in the mean plasma level of Pb in leukemic patients compared to controls (p&lt;0.05). This significant different was not observed in Cd, Hg and As (p&gt;0.05). The total antioxidant (TAP) reduced significantly in leukemic patient (p&lt;0.05), while the increased index of lipid peroxidation (MAD) was not significantly different from controls (p &gt;0.05). The plasma level of all the cytokine investigated was significant increase in acute leukemia patients compared with controls (p&lt; 0.05). Interestingly, Pb correlated inversely with TAP, and positively with Cd and Cytokines.

This study implicates Pb in the pathogenesis of leukemia in Nigeria patients. Pb, apart from its potential influence in enhancing toxic effect of other metals, especially Cd, possibly plays a role in depletion of antioxidant level in Leukemic patients. The reduction in total antioxidant may be in addition to increase consumption of antioxidants by aggressive production of free radical usually associated with acute leukemia. In addition, increase production of cytokine and its correlation with Pb and TAP may imply possible complications.

In conclusion, this study reveals a multiple contributing factors and possible complication in the grave prognosis of leukemia in Nigeria. These factors include Pb toxicity, reduced total antioxidant, increased lipid peroxidation and possible danger of ‘cytokine storm’. Thus, antioxidant supplementation may be worthwhile in early leukemia prophylaxis intervention and could possibly prevent the grave effect of complications associated with acute leukemia.

Citation Format: Oluyemi Akinloye, Mary Bolanle Ajadi, Adebayo M. Adegbenro, Ganiyu O. Arinola. Lead toxicity and oxidative stress: Possible causes of complications and grave prognosis in acute leukemic Nigeria patients. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1584. doi:10.1158/1538-7445.AM2014-1584