Prenatal PM 2.5 Exposure Induces Offspring Hypertension via Nrf2/NLRP3 Pathway

BACKGROUND: Adverse factors during pregnancy can significantly increase the incidence of hypertension in adult offspring. Activation of the sympathetic nervous system is closely associated with the development and progression of hypertension. METHODS: We established a model of offspring hypertension induced by prenatal fine particulate matter exposure to evaluate the role of the sympathetic nervous system activation. Quantitative immunofluorescence and Western blot analysis were used to assess the levels of activated and inhibitory sympathetic neurons. The effects of the central and peripheral sympathetic nervous systems were evaluated using clonidine and renal sympathetic denervation. In addition, the activation of microglia in the lateral ventricle region and the expression of the Nrf2 (nuclear factor E2-related factor)/ NLRP3 (NLR family pyrin domain-containing 3) signaling pathway were analyzed. RESULTS: The adult offspring showed increased neuronal hyperactivity and sympathetic nervous system activity. Specific inhibition of the central sympathetic nervous system and renal denervation effectively reversed the prenatal fine particulate matter-induced blood pressure elevation in adult offspring. In addition, overactivation of oxidative stress and microglia-mediated inflammation in the paraventricular nucleus was responsible for increased central sympathetic activity in the adult offspring exposed to prenatal fine particulate matter. Furthermore, we confirmed the critical role of the Nrf2/NLRP3 signaling pathway in oxidative stress and inflammation activation in the paraventricular nucleus of adult offspring. CONCLUSIONS: Overall, prenatal fine particulate matter exposure induces excessive inflammation and oxidative stress in paraventricular nucleus microglia through the Nrf2/NLRP3 signaling pathway, resulting in central and peripheral sympathetic overactivation, leading to hypertension and left ventricular hypertrophy.