Challenges of fluoride pollution in environment: Mechanisms and pathological significance of toxicity – A review.

Fluoride is an important trace element in the living body. A suitable amount of fluoride has a beneficial effect on the body, but disproportionate fluoride entering the body will affect various organs and systems, especially the liver, kidneys, nervous system, endocrine system, reproductive system, bone, and intestinal system. In recent years, with the rapid development of agriculture and industry, fluoride pollution has become one of the important factors of environmental pollution, and fluoride pollution in any form is becoming a serious problem. Although countries around the world have made great breakthroughs in controlling fluoride pollution, however fluorosis still exists. A large amount of fluoride accumulated in animals will not only produce the toxic effects, but it also causes cell damage and affect the normal physiological activities of the body. There is no systematic description of the damage mechanism of fluoride. Therefore, the study on the toxicity mechanism of fluoride is still in progress. This review summarizes the existing information of several molecular mechanisms of the fluoride toxicity comprehensively, aiming to clarify the toxic mechanism of fluoride on various body systems. We have also summerized the pathological changes of those organ systems after fluoride poisoning in order to provide some ideas and solutions to the reader for the prevention and control of modern fluoride pollution. ①After fluoride enters the body, it induces the production of caspase-12,caspase-9,caspase-3, caspase-7 through different ways, causes cell apoptosis and induces body damage. ②After fluoride enters the body, it induces the production of autophagy markers U1K1, Atg13, LC3 and Beclin1 through mTOR signaling pathway, resulting in autophagy.③ After fluoride enters the body, it affects the antioxidant system of various organs, inhibits the activity of antioxidant enzymes, increases reactive oxygen species and the occurrence of oxidative stress.④Fluoride promotes the degradation of IκBβ, activate NF-κB pathway, increase the content of proinflammatory cytokines TNF- α, IL-6 and IL-1 β, and induce inflammation. [Display omitted] • Fluoride exposure induces mitochondrial dysfunction. • Fluoride exposure mediates organs injury both in apoptosis and autophagy. • Fluoride exposure induces inflammatory reaction. • Fluoride exposure facilitates changes in intestinal microbial abundance. [ABSTRACT FROM AUTHOR]