Pathogenesis of morphological changes in organs and tissues in chronic fluoride intoxication (literature review)

Introduction. Traditionally, the main manifestation of chronic fluoride intoxication is the damage to the skeletal system, while during recent years a large amount of works has been accumulated on the study of the mechanism of action of both fluorine and its compounds on non-skeletal tissues. Based on the analysis of the Russian Science Citation Index, PubMed, Scopus, Web of Science, MedLine, Google Scholar, CyberLeninka databases, a review of contemporary concepts of morphological changes in organs and systems under the conditions of long-term exposure to fluorine compounds is presented.

Effect of fluorine on the musculoskeletal system. Fluorine Ihas been shown to induce differentiation and apoptosis of osteoblasts and osteoclasts, leading to various skeletal injuries. Active osteogenesis and accelerated bone metabolism are key processes in the progression of skeletal fluorosis and the pathological base of the diversity of osteogenic lesions.

Effect of fluorine on non-skeletal tissues. Data on the effect of fluorine on the induction of free radical oxidation in the cerebral cortex, redistribution, and damage to nerve cells are presented. Activation of apoptosis, oxidative stress, and a decrease in the activity of antioxidant enzymes under the influence of sodium fluoride in the heart muscle are shown, data on the development of functional and structural disorders in the myocardium are given. Due to fluoride intoxication, the formation of degenerative and inflammatory changes in the respiratory system, liver, and kidneys, structural disorders and dysfunction of the thyroid gland, as well as an increase in the level of reactive oxygen species and the induction of apoptosis in these organs are shown. Data on the effect of sodium fluoride on the histological structure of the reproductive organs with a decrease in sperm motility, lack of differentiation and maturation of spermatocytes, intensification of free radical oxidation and cell apoptosis are presented.

Conclusion. The analysis carried out allows expanding the understanding of the pathogenetic bases of morphological changes and functional failure of organs and tissues under the conditions of chronic fluoride intoxication, to substantiate a systemic, integrated approach to its treatment and prevention.

Contribution:
Bugaeva M.S. — concept and design of the study, collection and processing of material, writing a text;
Kazitskaya A.S., Yadykina T.K. — collection and processing of material;
Zhukova A.G. — collection and processing of material, text editing;
Mikhailova N.N. — concept of the study, text editing.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Acknowledgement. The study had no sponsorship.

Received: March 23, 2023 / Accepted: June 7, 2023 / Published: August 30, 2023

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