Combination of Fluoride and SO2 Induce DNA Damage and Morphological Alterations in Male Rat Kidney

Background/Aims: We investigated the combined toxic effect of sodium fluoride (NaF) and sulfur dioxide (SO2) on kidney morphological changes and DNA damage in male Wistar rats. Methods: In this study we selected totally 96 male Wistar rats (12-week-old) then randomly group-housed them into four cages, treated with deionized water, NaF, SO2 and co-treatment of NaF and SO2 respectively. Morphological changes of kidney were detected by hematoxylin and eosin (H&E) staining at 2, 4, 6 and 8 weeks. Correspondingly, tailing ratio and comet length were measured by BAB Bs Comet Assay System, including DNA damage special unit were calculated to evaluate the grades of kidney DNA damage at the same time. Results: Treated groups showed a body weight decrease when compared to control group. However, no significant difference in the relative weight of kidney was found in all four groups. It is noteworthy that at 2, 4, 6 and 8 weeks after exposure, the morphological alteration of renal tubules were observed in all treated groups, especially in group-IV. Also, at 4 and 6 weeks, notable DNA damage was found in all treated groups, as assessed by significantly increasing trend of comet length tailing ratio. Conclusion: The study manifests that presence of NaF and SO2 will not only induce renal tissue lesions but also impact DNA integrity. In addition, this combined exposure exhibits a synergistic effect, characterizing a dose-dependence and time correlation. These findings may provide novel insights regarding perturbations of DNA damage and its functions as a potential new mechanism, by which cautious interpretation of NaF and SO2 co-exposure evolved in both animals and human beings is necessary

BATF sustains homeostasis and functionality of bone marrow Treg cells to preserve homeostatic regulation of hematopoiesis and development of B cells

Bone marrow Treg cells (BM Tregs) orchestrate stem cell niches crucial for hematopoiesis. Yet little is known about the molecular mechanisms governing BM Treg homeostasis and function. Here we report that the transcription factor BATF maintains homeostasis and functionality of BM Tregs to facilitate homeostatic regulation of hematopoiesis and B cell development. Treg-specific ablation of BATF profoundly compromised proportions of BM Tregs associated with reduced expression of Treg effector molecules, including CD44, ICOS, KLRG1, and TIGIT. Moreover, BATF deficiency in Tregs led to increased numbers of hematopoietic stem cells (HSCs), multipotent progenitors (MPPs), and granulocyte-macrophage progenitors (GMPs), while reducing the functionality of myeloid progenitors and the generation of common lymphoid progenitors. Furthermore, Tregs lacking BATF failed to support the development of B cells in the BM. Mechanistically, BATF mediated IL-7 signaling to promote expression of effector molecules on BM Tregs and their homeostasis. Our studies reveal a previously unappreciated role for BATF in sustaining BM Treg homeostasis and function to ensure hematopoiesis