Lead is a heavy metal which is widespread in the environment, and the exposure to Pb during the body’s development can alter the gut microbiota. The aim of this study was to assess the effects of prenatal and neonatal exposure to lead (Pb) on the number of commensal intestinal bacteria in rats. Pregnant female rats received 0.1% lead acetate (PbAc) in drinking water supplied ad libitum. Pregnant females from the control group received distilled water. During the feeding of offspring, mothers from the experimental group were still receiving PbAc. The offspring were weaned at postnatal day 21. The number of enterococci was significantly lower in all the studied parts of the intestine of the rats pre- and neonatally exposed to PbAc than in the control group. The total number of coliforms in all the examined sections of the intestine was lower in the Pb-exposed group. In contrast, streptococci were found only in all the analysed parts of the intestine in the Pb-exposed animals. In the control group, yeasts were not found, contrary to the Pb-exposed group. The amount of Candida observed in the colon was approximately ten times higher than their amounts in every other examined section of the intestine. Prenatal and neonatal exposure to lead may decrease the number of coliforms and enterococci bacteria, and may promote colonization of the intestine by streptococci (especially in the duodenum) and yeasts (particularly in the colon). Streptococci and yeasts are more alkaline microorganisms than coliforms and enterococci. Exposure to Pb can effect changes in pH of the environment in the gastrointestinal tract and this way it can lead to the selection of specific species of bacteria.  

24.2.2019