Prenatal air pollution exposure to diesel exhaust induces cardiometabolic disorders in adulthood in a sex-specific manner.

BACKGROUND

Results from observational and experimental studies indicate that exposure to air pollutants during gestation reduces birth weight, whereas little is known on potential cardiometabolic consequences for the offspring at adulthood.

OBJECTIVES

Our aim was to evaluate the long-term effects of gestational exposure to diesel engine exhaust (DE) on adult offspring phenotype in a rabbit model.

METHODS

The protocol was designed to mimic human exposure in large European cities. Females rabbits were exposed to diluted (1 mg/m3) DE (exposed, n = 9) or clean air (controls, n = 7), from 3 days after mating, 2 h/d and 5 d/wk in a nose-only inhalation system throughout gestation (gestation days 3-27). After birth and weaning, 72 offspring (47 exposed and 25 controls) were raised until adulthood (7.5 months) to evaluate their cardio-metabolic status, including the monitoring of body weight and food intake, fasting biochemistry, body composition (iDXA), cardiovascular parameters and glucose tolerance. After a metabolic challenge (high fat diet in males and gestation in females), animals were euthanized for postmortem phenotyping.

RESULTS

Sex-specific responses to maternal exposure were observed in adult offspring. Age-related increases in blood pressure (p = 0.058), glycaemia (p = 0.029), and perirenal fat mass (p = 0.026) as well as reductions in HDL-cholesterol (p = 0.025) and fat-to-body weight ratio (p = 0.011) were observed in exposed males, suggesting a metabolic syndrome. Almost only trends were observed in exposed females with higher triglycerides and decreased bone density compared to control females. Metabolic challenges triggered or amplified some biological responses, especially in females.

CONCLUSIONS

In utero exposure to air pollution predisposed rabbit offspring to cardiometabolic disorders in a sex-specific manner.