Salivary parameters alterations after early exposure to environmental methylmercury: A preclinical study in offspring rats

J Trace Elem Med Biol. 2021 Dec:68:126820. doi: 10.1016/j.jtemb.2021.126820. Epub 2021 Jul 16.

Abstract

Background: Methylmercury (MeHg) is still considered a global pollutant of major concern; thus, it becomes relevant to investigate and validate alternative diagnostic methods to track early-life human exposure. This study aimed to evaluate the salivary parameters and to characterize potential mechanisms of oxidative damage on the salivary glands (SG) of offspring rats after pre- and postnatal environmental-experimental MeHg exposure.

Methods: Pregnant Wistar rats were daily exposed to 40 μg/kg MeHg during both gestational and lactation periods. Then, the saliva of offspring rats was analyzed in terms of flow rate, amylase activity, and total protein concentration. The SG of the offspring rats were dissected to perform the oxidative biochemistry analyses of antioxidant capacity against peroxyl radicals (ACAP), lipid peroxidation (LPO), and nitrite levels.

Results: Exposure to MeHg significantly decreased the ACAP, increased LPO and nitrite levels, decreased salivary flow rate, amylase activity, and total protein concentration.

Conclusion: Saliva analyses can predict damages induced by early-life MeHg exposure and may be used as an auxiliary diagnostic method.

Keywords: Development; Methylmercury; Saliva; Salivary glands; Toxicology.

MeSH terms

  • Amylases
  • Animals
  • Female
  • Lipid Peroxidation
  • Methylmercury Compounds* / toxicity
  • Nitrites
  • Oxidative Stress
  • Pregnancy
  • Rats
  • Rats, Wistar

Substances

  • Methylmercury Compounds
  • Nitrites
  • Amylases