Experimental exposure to gasohol impairs sperm quality with recognition of the classification pattern of exposure groups by machine learning algorithms.

Contamination caused by leakage at gas stations leads to possible exposure of the general population when in contact with contaminated water and soil. The present study aimed to evaluate the reproductive effects of exposure of adult male rats to gasohol and evaluate the performance of machine learning (ML) algorithms for pattern recognition and classification of the exposure groups. Rats were orally exposed to 0 (control), 16 (EA), 160 (EB), or 800 mg kg-1 bw day-1 of gasohol (EC), for 30 consecutive days. Sperm quality of the groups exposed to two higher doses was reduced in comparison to the control group. The sperm parameters decreased were: daily sperm production, sperm number in the caput/corpus epididymis, progressive motility, mitochondrial activity, and acrosomal membrane integrity. Sperm transit time in the epididymis cauda and sperm isolated head were increased in EB and EC. Sertoli cells number was decreased in these groups, but their support capacity was maintained. ML methods were used to identify patterns between samples of control and exposure groups. The results obtained by ML methods were very promising, obtaining about 90% of accuracy. It was concluded that the exposure of rats to different doses of gasohol impair spermatogenesis and sperm quality, with a recognizable classification pattern of exposure groups at ML.

Experimental exposure to 3 monochloropropane 1, 2 diol from the pre puberty causes damage in sperm production and motility in adulthood / Exposição experimental ao 3 monocloropropano 1, 2 diol, a partir da pré puberdade, causa alteração na produção e motilidade espermática na idade adulta

3-Monochloropropane-1,2-diol (3-MCPD) is a food contaminant that can be formed during the thermic processing of various foodstuffs. Studies of reproductive toxicology of 3-MCPD are mainly concentrated in the evaluation of possible insults caused by exposure of adult animals. However, the prepuberty might be a period of different susceptibility to chemicals. The aim of this study was to evaluate the effects on reproductive endpoints of the 3-MCPD-exposure prepubertal male rats. Wistar male rats were assigned to 4 groups: control and exposed to 2.5; 5 or 10 mg kg-1 day-1 of 3-MCPD for 30 days by gavage. Testis and epididymis were used for sperm counts and histology analysis. Sertoli cell number and dynamic of the spermatogenesis were evaluated. Sperm were collected from the vas deferens for evaluation of the sperm motility and morphology. Number of sperm with progressive movement, number of Sertoli cells and germ cells and relative daily sperm production were decreased in the groups exposed to 5 and 10 mg kg-1 day- 1 of 3-MCPD. Sperm morphology, testicular and epididymal histology were comparable among groups. Results show that 3-MCPD-exposure of rats from prepuberty might cause alterations in spermatogenesis and sperm maturation, similarly to exposure in adulthood.

3-monocloropropano-1,2-diol (3-MCPD) é um contaminante alimentar formado durante o processamento térmico de vários produtos. Estudos de toxicologia reprodutiva do 3-MCPD estão concentrados principalmente na avaliação de danos causados pela exposição de animais adultos. No entanto, a peri-puberdade pode ser um período de susceptibilidade diferente a produtos químicos. O objetivo deste estudo foi avaliar os efeitos reprodutivos da exposição de ratos machos pré-púberes ao 3-MCPD. Ratos Wistar machos foram divididos em quatro grupos: controle e expostos a 2,5; 5 ou 10 mg kg-1 dia-1 de 3-MCPD durante 30 dias, por gavagem. Os testículos e epidídimos foram usados para contagem espermática e análise histológica. Foram avaliados o número de células de Sertoli e a dinâmica da espermatogênese. Espermatozoides foram coletados a partir dos ductos deferentes para avaliação da motilidade e morfologia. O número de espermatozoides com movimento progressivo, o número de células de Sertoli e de células germinativas e a produção espermática foram reduzidos nos grupos expostos a 5 e 10 mg kg-1 dia-1 de 3-MCPD. A morfologia espermática e histologia testicular e epididimária foram semelhantes entre os grupos. Os resultados mostram que a exposição de ratos ao 3-MCPD, a partir da pré-puberdade, pode causar alterações na espermatogênese e na maturação espermática, de forma semelhante à exposição na idade adulta.

Maternal and fetal toxicity of Wistar rats exposed to herbicide metolachlor / Toxicidade materna e fetal de ratas Wistar expostas ao herbicida metolacloro

Metolachlor is a selective pre-emergent herbicide widely used in agriculture to control weeds. The aim of this study was to evaluate the possible effects of metolachlor on reproductive performance of adult rats, as well as its teratogenic potential when administered during the period of organogenesis. Pregnant adult female rats were allocated into 4 experimental groups (n = 10 group-1), that received 0 (control); 150 (TA); 300 (TB); or 1000 mg kg-1 bw day-1 (TC) of metolachlor, by gavage, from the 6th to 15th gestational day (GD). There is reduction in the weight gain of the animals from TB and TC groups compared to the control group. Liver and placenta weights were reduced in TB and TC groups, respectively, while the percentage of post-implantation loss was increased in the TC group. There were no external malformations in either rat of the control or treated groups. However, an increased incidence of skeletal anomalies and visceral anomalies (especially in the urogenital system) was observed in TC group. These results demonstrate that exposure of pregnant rats to metolachlor can lead to signs of general toxicity, late embryonic losses and congenital anomalies.

O metolacloro é um herbicida seletivo de pré-emergência, amplamente usado na agricultura para controlar ervas daninhas. O objetivo deste estudo foi avaliar os possíveis efeitos do metolacloro sobre o desempenho reprodutivo de ratas adultas, bem como o seu potencial teratogênico quando administrado durante o período da organogênese. Ratas adultas prenhes foram divididas em quatro grupos experimentais (n = 10 grupo-1), que receberam 0 (controle); 150 (TA); 300 (TB); ou 1.000 mg kg-1 dia-1 (TC) do metolacloro, via gavagem, do sexto ao 15º dia de gestação (DG). Foi observada redução no ganho de peso dos animais dos grupos TB e TC em comparação ao grupo controle. Os pesos do fígado e placenta foram reduzidos nos grupos TB e TC, respectivamente, enquanto que a percentagem de perda pós-implantação foi aumentada no grupo TC. Não foram observadas malformações externas nos ratos dos grupos controle e tratados. No entanto, foi observado aumento da incidência de anomalias esqueléticas e anomalias viscerais (especialmente no sistema urogenital) no grupo TC. Estes resultados demonstram que a exposição de ratas prenhes ao metolacloro pode levar a sinais de toxicidade geral, perdas embrionárias tardias e anomalias congênitas.