Abstract
Excessive fluoride intake from residential environments may affect multiple tissues and organs; however, the specific pathogenic mechanisms are unclear. Researchers have recently focused on the damaging effects of fluoride on the immune system. Damage to immune function seriously affects the quality of life of fluoride-exposed populations and increases the incidence of infections and malignant tumors. Probing the mechanism of damage to immune function caused by fluoride helps identify effective drugs and methods to prevent and treat fluorosis and improve people’s living standards in fluorosis-affected areas. Here, the recent literature on the effects of fluoride on the immune system is reviewed, and research on fluoride damage to the immune system is summarized in terms of three perspectives: immune organs, immune cells, and immune-active substances. We reviewed that excessive fluoride can damage immune organs, lead to immune cells dysfunction and interfere with the expression of immune-active substances. This review aimed to provide a potential direction for future fluorosis research from the perspective of fluoride-induced immune function impairment. In order to seek the key regulatory indicators of fluoride on immune homeostasis in the future.
Article online at https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2024.1394161/full
Excerpt:
5 Conclusion
An increasing number of researchers have focused on the damage to the immune system caused by endemic fluorosis, and substantial progress has been made in understanding the mechanism of immune system damage. Recent studies have shown that fluoride damages the immune system primarily via oxidative stress pathways, signaling pathways, cell apoptosis, and cell activity. For example, several studies have found that fluoride regulates cell differentiation and development primarily via the oxidative stress pathway when it damages immune organs such as the thymus and spleen, thus leading to cell apoptosis and inhibition of relevant signaling pathways. Therefore, immune system damage warrants further exploration. These findings provide a new direction for studying other fluoride-induced immune dysfunctions and lay the foundation for subsequent studies at the molecular level.
In this review, we found that fluoride affects both cellular and humoral immunity. Fluoride decreases the number and activity of immune cells, causing an imbalance in the Th1/Th2 cells. However, an imbalance in the Th1/Th2 cell ratio may lead to a response from the body’s immune system to its components, leading to autoimmune diseases. In contrast, T lymphocyte subsets in peripheral blood are changed, the number of auxiliary T lymphocytes is reduced and the number of inhibitory T lymphocytes is relatively high, leading to tumor immunosuppression, which affects the occurrence and development of tumors (Figure 1).
