Tumor-promoting activity of p-hydroxybenzenediazonium is accelerated in Mg-deficient rats

Abstract

Tumor-promoting activity caused by the short-term administration of p-hydroxybenzenediazonium (PDQ) has been assayed in rats fed on a Mg-deficient diet as a reference model versus rats fed on a standard diet as controls. For 5 weeks groups of 20 rats, fed either on the Mg-deficient or standard diet, were treated simultaneously with PDQ. A group of 10 Mg-deficient rats remained untreated. Topical application of PDQ was followed by the appearance of macroscopic alterations in the skin, which were more evident in the Mg-deficient rats. No deaths occurred during the treatment. After 5 weeks' PDQ treatment the rats were killed and histological analyses were made. Tissues from the skin, liver, heart, kidney, lung and thymus were screened by conventional staining methods. Both the PDQ-treated Mg-deficient and PDQ-treated control rats presented tissue lesions, although to a different extent. The untreated Mg-deficient rats showed no such lesions. Mg-deficient rats treated with PDQ developed significant incipient fibrosarcomas (p < 0.05) and extended hyperplasia (p < 0.001), particularly in the skin, accompanied by a significant increase in the thickness of collagen (mean value: 445.4 ± 47.2 m, p < 0.05) compared to the control PDQ-treated group (mean values: 258.7 ± 36.4 m). The overall results provide objective proof of tumor-promoting activity after 5 weeks' treatment with PDQ. Such a fast response is interpreted as being linked to the increased vulnerability of the membrane caused by Mg deficiency, which would more readily facilitate the toxic activity of p-hydroxybenzenediazonium ions.

Disturbed homeostasis of zinc and other essential elements in the prostate gland dependent on the character of pathological lesions

“…On the other hand, changes in Mg levels in cells may induce a number of pathological lesions. Magnesium among its other functions stabilizes cellular membranes, and its insufficient supply enhances the permeability of cell membranes and sensitivity to oxygen free radicals, leading to the generation of numerous cellular abnormalities (Wolf et al 2007;Quintero et al 2006).…”