Maternal engineered nanomaterial exposure and fetal microvascular function: does the Barker hypothesis apply?

Area of Science:

• Environmental Toxicology
• Cardiovascular Physiology
• Developmental Biology

Background:

• Engineered nanomaterials (ENM) raise concerns regarding human health effects, particularly cardiovascular toxicity.
• The maternal system's unique demands during pregnancy require further investigation for ENM impacts.
• The Barker hypothesis suggests prenatal environmental conditions influence future health.

Purpose of the Study:

• To investigate if maternal ENM exposure affects uterine and fetal microvascular function.
• To evaluate the applicability of the Barker hypothesis at the microvascular level in the context of maternal ENM exposure.

Main Methods:

• Pregnant Sprague-Dawley rats were exposed to nano-titanium dioxide aerosols.
• Maternal uterine and fetal tail arteries were isolated on gestation day 20.
• Arteriolar reactivity was assessed using pharmacologic and mechanical stimuli.

Main Results:

• Engineered nanomaterial exposure caused significant maternal and fetal microvascular dysfunction.
• Compromised endothelium-dependent and -independent reactivity was observed in both maternal and fetal vessels.
• Maternal exposure created a hostile gestational environment, impacting fetal weight and microvascular vasodilation signaling.

Conclusions:

• Maternal inhalation of engineered nanomaterials adversely affects fetal health.
• This study provides the first evidence that the Barker hypothesis is relevant at the microvascular level.
• Maternal ENM exposure leads to impaired fetal microvascular function and supports the concept of developmental programming.