RESUMEN
This study investigated the fluctuation of NF-KB and HIF-1a gene expression between inhabitants of a high-level background radiation area (HBRA) and a normal-level background radiation area (NBRA) of Ramsar, Iran. Sixty participants with the mean age of 48 ± 15 years were selected and divided into two groups. The group receiving a dose of ≤1.5 mGy/year (NBRA) was considered the control group and the target group (HBRA) received a dose of >1.5 mGy/year. These two groups were from neighbor regions to minimize socioeconomic differences between the participants. Blood samples were collected from each group and NF-KB and HIF-1a expression levels were compared using quantitative real-time PCR (qPCR) based on the stem loop method. The effects of residency duration in the respective areas and gender on the expression of NF-KB and HIF-1a was also examined. The HIF-1a expression level was statistically lower in the HLBRA region (P < 0.0002), while NF-KB expression was upregulated (P < 0.0001). Although the under-expression of HIF-1a in response to dose rate was significant in females (P < 0.0004), it was not different in males (P = 0.74), indicating a significant difference between sexes (P = 0.0047). The upregulation of NF-KB expression related to dose level was also significant for the female group (P < 0.0001), whereas it was not for the male group (P = 0.72). Notably and as expected, there was a significant relation between longer residency in the HBRA and HIF-1A under-expression (P < 0.026), while there was no effect of increasing residency time for NF-KB over-expression level (P = 0.29). The dwellers of the HBRA those noted that despite receiving an elevated radiation level were seemingly good in general health, showed some alterations in their molecular mechanisms, specifically HIF-1a and NF-KB expression levels. It is not clear if this is indicative of a beneficial adaptive response and more research is recommended.
