Thiamine prevents X-ray induction of genetic changes in human lymphocytes in vitro.

Abstract

The effects of thiamine (vitamin B1) on the level of spontaneous or radiation-induced genetic changes in human lymphocytes in vitro were studied. Cultured lymphocytes were exposed to increasing concentrations of thiamine (0-500 microg/ml) and irradiated with X-rays. The DNA damage was estimated as the frequency of micronuclei and apoptotic or necrotic morphological changes in fixed cells. The results show that thiamine alone did not induce genetic changes. A significant decrease in the fraction of apoptotic and necrotic cells was observed in lymphocytes irradiated in the presence of vitamin B1 at concentrations between 1-100 microg/ml compared to those irradiated in the absence of thiamine. Vitamin B1 at 1 and 10 microg/ml decreased also the extent of radiation-induced formation of micronuclei. Vitamin B1 had no effect on radiation-induced cytotoxicity as measured by nuclear division index. The results indicate that vitamin B1 protects human cells from radiation-induced genetic changes.

Antioxidant and Prooxidant Activities of B Group Vitamins in Lipid Peroxidation

“…The lowest concentration (1 pg/ml) of vitamin Bi more effectively prevented X ray-induced DNA damage and cytotoxicity of human Iymphocytes than higher concentrations (10'500 pg/ml) of vitamin Bi [14]. Furthermore, as a preliminary experiment, we examined the effect of a much lower concentration (O.25 pM) of vitamin Bi on lipid peroxidation, and the strong antioxidant activities were also observed in later phase (3 weeks) reactions (data llot shown).…”

Boric acid as a protector against paclitaxel genotoxicity.

“…where 1N is number of cells with one nucleus, 2Nwith two nuclei, and >2N -with more than two nuclei, C -number of cells examined (Konopacka & Rogolinski, 2004).…”

Ascorbic acid, thiamine or salicylic acid induced changes in some physiological parameters in wheat grown under copper stress

“…Moreover, the thiazole biosynthetic enzyme of yeast and Arabidopsis appear to be a dual functional protein with the role in thiamine biosynthesis and mitochondrial DNA damage tolerance (Machado et al 1996(Machado et al , 1997. Although there is no direct evidence to support the hypothesis, the DNA damage tolerance associated with the thiazole biosynthetic enzymes of yeast and Arabidopsis may be due to the action of thiamine as observed in human lymphocytes in which the radiation-induced genetic changes can be protected by thiamine (Konopacka & Rogolinski 2004). Besides its physiological and genetic importance, priming by thiamine could be one of the most economical and effective resistances because the expression of defence-related mechanisms in the absence of pathogen requires the plant's metabolic investment necessary for growth or other fitness-related processes (Purrington 2000;Heil 2001; Van Hulten et al 2006).…”