| Background and ObjectLead(Pb)is a kind of toxic heavy metal which is ubiquitous in living environment and occupational environment,it can enter the body through respiratory tract,digestive tract and skin,then injure nerve,hematopoietic,digestive tract and reproduction and so on.It would affect human health seriously through long-term exposure to high lead environment,especially on the neural system of children.The prominent feature of developmental lead neurotoxicity is that lead exposure can affect hippocampal synaptic function through placenta and blood-brain barrier,resulting in the decrease of learning,memory and cognitive function.At present,metal complexing agents are often used for the treatment of lead poisoning,such as disodium dicarbonate(CaNa2EDTA),2,3-dimercaptosuccinic acid(DMSA).Studies have shown that metal complexing agents can produce persistent gastrointestinal adverse reactions,"hypercomplexation syndrome",hepatorenal toxicity and other toxic and side effects.So it doesn't apply to pregnant women,lactating women and children.Therefore,it is urgent to develop a new method for the treatment of lead poisoning.In view of gut microbiota play a critical role in maintaining human health,the development of probiotics to prevent human from lead toxicity has received grievous attention.Our study was planned to isolate a Lactobacillus casei stain from healthy newborn feces which owned outstanding probiotics function and strong capability of Pb bio-adsorption.To investigate its protective effect on Pb exposed mother and its offspring,the Lactobacillus casei stain was administration in Pb exposed dams during pregnancy and lactation.Methods1.The lead poisoning model of offspring mice induced by lead exposure in female mice during pregnancy and lactation was established by using adultmice without specific pathogen(SPF).The offspring mice were killed at the age of 21 days after drinking lead water with the concentration of 100mg/1 by female mice.The body weight and the weight of liver,kidney,brain and other organs of offspring were measured;blood,bone,brain,kidney,liver and small intestine were taken to detect the concentration of lead;GSH?GSH-Px?SOD and NOwere used to detect oxidative stress factors;and HE staining was performed to evaluate the pathological injury of brain and small intestine.In order to investigate the effect of probiotics on lead poisoning mice,we selected Lactobacterium rhamnosus GG(LGG)to interfere with female mice which exposed to lead.2.A Lactobacillus casei strain was isolated from the healthy newborns feces and its biochemical characteristics,probiotics functions and the ability of Pb bio-adsorption were determined.3.By using the successful model of lead poisoning offspring induced by lead exposure in female mice was established in l,the Lactic acid bacteria selected in 2were used to interfere with the female mice.The body weight and the weight of liver,kidney,brain,blood,bone,brain,kidney,liver of female mice and offspring were measured;NO in offspring's liver and kidney were detect;16s RNA sequencing of feces were measured;and HE staining was performed to evaluate the pathological injury of brain and small intestine.To investigate the protective effect of lactic acid bacteria with lead adsorption on lead exposed maternal mice and offspring mice.Results1.Female rats were exposed to Pb by drinking 100mg/1 lead acetate deionized water would induce to offspring were suffer lead poisoning.It was successful to established the mice model of lead poisoning offspring induced by maternal Pb exposure.2.Administration female mice by LGG via gavage could alleviate the damage of Pb-poisoning offspring,suggest that the protective effect of LGG on Pb poisoning offspring.3.A Lactobacillus casei strain named SYF-08 was isolated from healthy newborn faeces own the advantages of stable growth,outstanding probiotics function,stable adhesion to intestinal cells and excellent ability of Pb bio-adsorption.In 250 ppm lead solution,the lead adsorption rate of SYF-08 reached 51.00 to 6.81%,and SYF-08 was still able to grow on the MRS sugar plate with lead concentration of 2500 mg/L.4.The concentration of Pb in the dams' blood,bone,kidney and offspring'^blood,brain,kidney were significantly decreased after intervention of SYF-08 on Pb exposure female mice,the pathological damage of intestine and brain tissue was effectively alleviated and the activity of NO in liver and kidney of offspring was significantly decreased.The diversity and composition of intestinal flora in offspring rats were restored.ConclusionPersistent lead exposure on maternal mice by drinking water would induce offspring suffer Pb-poisoning.Intervention of SYF-08 isolated from healthy newborn feces on lead-exposed maternal mice could effectively reduce Pb accumulation in important tissues and organs of dams and offspring mice,alleviate oxidative stress damage in liver and kidney of offspring,maintain the cerebral cortex and small intestine health physiological structure of dams and offspring,and maintain the stability of the intestinal flora in the offspring.The study suggested that Lactobacillus casei SYF-08 show protective effect on Pb exposure maternal mice and their offspring. |
PDF Full Text Request