The effect of short term exposure to outdoor air pollution on fertility

Background There is evidence to suggest that long term exposure to air pollution could be associated with decreased levels of fertility, although there is controversy as to how short term exposure may compromise fertility in IVF patients and what windows of exposure during the IVF process patients could be most vulnerable. Methods This prospective cohort study aimed to evaluate the impact of acute exposure that air pollution have on reproductive outcomes in different moments of the IVF process. Women undergoing IVF living in Barcelona were recruited. Individual air pollution exposures were modelled at their home address 15 and 3 days before embryo transfer (15D and 3D, respectively), the same day of transfer (D0), and 7 days after (D7). The pollutants modelled were: PM2.5 [particulate matter (PM) ≤2.5 μm], PMcoarse (PM between 2.5 and 10μm), PM10 (PM≤10 μm), PM2.5 abs, and NO2 and NOx. Outcomes were analyzed using multi-level regression models, with adjustment for co-pollutants and confouding factors. Two sensitivity analyses were performed. First, the model was adjusted for subacute exposure (received 15 days before ET). The second analysis was based on the first transfer performed on each patient aiming to exclude patients who failed previous transfers. Results One hundred ninety-four women were recruited, contributing with data for 486 embryo transfers. Acute and subacute exposure to PMs showed a tendency in increasing miscarriage rate and reducing clinical pregnancy rate, although results were not statistically significant. The first sensitivity analysis, showed a significant risk of miscarriage for PM2.5 exposure on 3D after adjusting for subacute exposure, and an increased risk of achieving no pregnancy for PM2.5, PMcoarse and PM10 on 3D. The second sensitivity analysis showed a significant risk of miscarriage for PM2.5 exposure on 3D, and a significant risk of achieving no pregnancy for PM2.5, PMcoarse and PM10 particularly on 3D. No association was observed for nitrogen dioxides on reproductive outcomes. Conclusions Exposure to particulate matter has a negative impact on reproductive outcomes in IVF patients. Subacute exposure seems to increase the harmful effect of the acute exposure on miscarriage and pregnancy rates. Nitrogen dioxides do not modify significantly the reproductive success.

Potential Neuroprotective Effect of Nanomicelle Curcumin on Learning and Memory Functions Following Subacute Exposure to Bisphenol a in Adult Male Rats

ObjectiveBisphenol A (BPA) is an endocrine-disrupting chemical that widely used in plastics production. It can influence on the brain tissue. Curcumin has a strong protective activity against brain disorders. The purpose of this study was to evaluate the protective effect of nanomicelle curcumin (NmCur) on BPA-induced learning and memory disorders in rats.Material and methodsIn this study, after determining the dose of BPA, rats were randomly divided into 8 groups (8 rats in each group); sesame oil, dextrose 5%, sesame oil + dextrose 5%, NmCur (50 mg/kg), BPA (50 mg/kg), and 50 mg/kg BPA plus 10, 25, or 50 mg/kg NmCur, respectively. All materials administered via gavage. Behavioral tests were estimated by shuttle-box, open-field, and Morris water maze devices. Then, stress oxidative, pro-inflammatory cytokines, oxidative stress-scavenging enzymes levels, as well as expression of MAPK proteins, glutamate receptors, and memory-related proteins were determined in the hippocampus and cortex tissues. ResultsBPA significantly increased expression of ROS, MDA, TNF-α, IL-6, IL-1β, SOD, GST, p-P38, and p-JNK; however, considerably decreased GSH, GPx, GR, CAT, p-AKT, p-ERK1/2 levels. In addition, it down regulated expression of p-NR1, p-NR2A, p-NR2B, p-GluA1, BDNF, and p-CREB in rat cortex and hippocampus tissues. BPA significantly also changed behavioral activity. Conversely, BPA (50 mg/kg) plus NmCur (25 and 50 mg/kg) significantly reversed all BPA-induced adverse effects. ConclusionThe results of this study support that nanomicelle curcumin exhibited preventive effects against neurotoxicity and learning and memory impairment induced by subacute exposure to bisphenol A.

Subacute Exposure to an Environmentally Relevant Dose of Di-(2-ethylhexyl) Phthalate during Gestation Alters the Cecal Microbiome, but Not Pregnancy Outcomes in Mice

Di-2-ethylhexyl phthalate (DEHP) is a plasticizer commonly found in polyvinyl chloride, medical equipment, and food packaging. DEHP has been shown to target the reproductive system and alter the gut microbiome in humans and experimental animals. However, very little is known about the impact of DEHP-induced microbiome changes and its effects during pregnancy. Thus, the objective of this study was to investigate the effects of DEHP exposure during pregnancy on the cecal microbiome and pregnancy outcomes. Specifically, this study tested the hypothesis that subacute exposure to DEHP during pregnancy alters the cecal microbiome in pregnant mice, leading to changes in birth outcomes. To test this hypothesis, pregnant dams were orally exposed to corn oil vehicle or 20 µg/kg/day DEHP for 10 days and euthanized 21 days after their last dose. Cecal contents were collected for 16S Illumina and shotgun metagenomic sequencing. Fertility studies were also conducted to examine whether DEHP exposure impacted birth outcomes. Subacute exposure to environmentally relevant doses of DEHP in pregnant dams significantly increased alpha diversity and significantly altered beta diversity. Furthermore, DEHP exposure during pregnancy significantly increased the relative abundance of Bacteroidetes and decreased the relative abundance of Firmicutes and Deferribacteres compared with controls. The affected taxonomic families included Deferribacteraceae, Lachnospiraceae, and Mucisprillum. In addition to changes in the gut microbiota, DEHP exposure significantly altered 14 functional pathways compared with the control. Finally, DEHP exposure did not significantly impact the fertility and birth outcomes compared with the control. Collectively, these data indicate that DEHP exposure during pregnancy shifts the cecal microbiome, but the shifts do not impact fertility and birth outcomes.

Effects of Subacute Exposure of Dibutyl Phthalate on the Homeostatic Model Assessment, Thyroid Function, and Redox Status in Rats

Dibutyl phthalate is an endocrine disruptor used in a wide range of industrial and agriculture applications. The present study focuses on elucidating the effect of subacute exposure (4-weeks) of DBP on insulin and its sensitivity indexes, oxidative status, thyroid function, energy metabolites, serum biochemistry, and anthropometry in rats. A total of 64 rats were divided into 4 treatment groups as mg DBP/Kg body weight per day: (a) 0 mg/Kg (control), (b) 10 mg/Kg (DBP-10), (c) 50 mg/Kg (DBP-50), and (d) 100 mg/Kg (DBP-100). The rats in each treatment ( n = 16 ) were further divided into male ( n = 8 ) and female ( n = 8 ) rats for studying treatment and gender interactions. Intraperitoneal glucose tolerance test (IPGTT) was performed on the 21st day. Anthropometry, nutritional determinants, fasting plasma glucose, fasting plasma insulin, homeostatic model assessment (HOMA), thyroid hormones, energy metabolites, and oxidative status were studied during the experimental period. Two-way ANOVA was used to analyze the data ( p < 0.05 ). Tukey’s posthoc test was used for pair-wise comparisons. DBP increased body weight gain and feed efficiency in an inverted nonmonotonic U -shaped fashion. Hyperglycemia and increased blood glucose area under the curve were observed in DBP-100 at 120 minutes in IPGTT. The HOMA also showed a linear monotonic contrast. Thyroxin decreased significantly in the DBP-100 rats, whereas malondialdehyde, nonesterified fatty acids, and beta hydroxyl butyrate were increased with the DBP treatments. In conclusion, DBP could be attributed to the development of hyperglycemia and insulin resistance in rats. Further investigations into the lipid peroxidation pathways can improve our understanding of the mechanisms involved in metabolic disruption.