Effects of fluoride exposure on kidney injury and SIRT3-FOXO3a-PINK1/PARKIN pathway in rats
10.3760/cma.j.cn231583-20231118-00109
- VernacularTitle:氟暴露对大鼠肾脏损伤及SIRT3-FOXO3a-PINK1/PARKIN通路的影响
- Author:
Juhui SONG
1
;
Wenwen HE
;
Ruichao LI
;
Yunyan LUO
;
Ting ZHANG
;
Chanjuan WANG
;
Yangting DONG
;
Yan HE
Author Information
1. 贵州医科大学地方病与少数民族疾病教育部重点实验室 贵州省医学分子生物学重点实验室 省部共建地方病及民族区域性疾病防控协同创新中心，贵阳 550004
- Keywords:
Fluorine;
Rat;
Mitochondrial autophagy;
Sirtuin 3-fork head protein O3a;
Tensin homolog induced putative kinase 1/E3 ubiquitin ligase
- From:
Chinese Journal of Endemiology
2024;43(7):528-535
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the effects of fluoride exposure on kidney injury in rats and the sirtuin 3 (SIRT3)-fork head protein O3a (FOXO3a)-tensin homolog induced putative kinase 1 (PINK1)/E3 ubiquitin ligase (PARKIN) pathway.Methods:Twenty-four 4-week-old SD rats (clean grade, body mass 100 - 150 g) were selected and divided into three groups according to the randomized numeric table: control group, low fluoride group, and high fluoride group, with eight rats in each group (half male and half female). The control group was given free access to tap water (fluoride ion concentration < 0.5 mg/L), while the low fluoride and high fluoride groups were given free access to tap water and sodium fluoride solutions with fluoride ion concentrations of 5.0 and 50.0 mg/L, respectively, for a period of 180 days. The formation of dental fluorosis in rats was observed and recorded, and the femur, urine and blood samples of rats were collected to measure bone fluoride, urinary fluoride, and blood fluoride levels, and to detect kidney function related indicators (serum uric acid, creatinine, and urea nitrogen contents). Morphological changes of renal tissues stained with hematoxylin-eosin (HE) were observed under a light microscope. Real-time fluorescence quantitative PCR (qRT-PCR) and Western blotting were used to detect the mRNA and protein expression levels of renal SIRT3, FOXO3a, PINK1, PARKIN, microtubule associated protein 1 light chain 3 (LC3), autophagy receptor protein (P62), respectively.Results:Seven and one rats in the low and high fluoride groups were found to haveⅠdegree dental fluorosis, while zero and seven rats were found to haveⅡdegree dental fluorosis. Compared with the control group, rats in the low and high fluoride groups had higher levels of bone fluoride (μg/g: 1.18 ± 0.06, 2.16 ± 0.07 vs 0.52 ± 0.05), urinary fluoride (mg/L: 4.43 ± 0.11, 7.46 ± 0.09 vs 2.58 ± 0.14), blood fluoride (μg/ml: 0.77 ± 0.06, 1.68 ± 0.10 vs 0.52 ± 0.08), serum uric acid (μg/ml: 61.01 ± 4.17, 103.92 ± 5.43 vs 28.68 ± 2.91), creatinine (μg/ml: 74.82 ± 9.61, 132.05 ± 5.35 vs 22.38 ± 4.11), and urea nitrogen (μg/ml: 13.36 ± 1.27, 14.55 ± 0.34 vs 0.29 ± 0.07, P < 0.05). Under the light microscope, the kidneys of the control group showed tight and orderly arrangement of renal tubules and glomerular cells, with complete and clear cell contours. The low fluoride group was similar to the control group and no significant abnormalities were observed. The high fluoride group showed abnormal glomerular structure and atrophy, with some areas of renal tubules showing epithelial cell edema and unclear intercellular boundaries. The results of qRT-PCR assay showed that compared with the control group, the low and high fluoride groups had lower mRNA expression levels of SIRT3 (0.82 ± 0.03, 0.58 ± 0.02 vs 1.00 ± 0.08), P62 (0.75 ± 0.07, 0.28 ± 0.09 vs 1.00 ± 0.07, P < 0.05), and higher mRNA expression levels of FOXO3a (1.35 ± 0.04, 3.01 ± 0.23 vs 1.00 ± 0.08), PINK1 (1.58 ± 0.09, 3.28 ± 0.09 vs 1.00 ± 0.07), PARKIN (1.51 ± 0.04, 1.67 ± 0.10 vs 1.00 ± 0.05), LC3 (1.74 ± 0.07, 2.38 ± 0.18 vs 1.00 ± 0.08, P < 0.05). The results of Western blotting showed that compared with the control group, the low and high fluoride groups had lower protein expression levels of SIRT3 (0.91 ± 0.01, 0.55 ± 0.03 vs 1.00 ± 0.01), P62 (0.94 ± 0.27, 0.66 ± 0.38 vs 1.00 ± 0.19, P < 0.05), and higher protein expression levels of FOXO3a (1.14 ± 0.03, 1.22 ± 0.05 vs 1.00 ± 0.02), PINK1 (1.46 ± 0.03, 1.56 ± 0.03 vs 1.00 ± 0.05), PARKIN (1.98 ± 0.02, 2.33 ± 0.11 vs 1.00 ± 0.06), LC3 (4.10 ± 0.58, 4.93 ± 0.33 vs 1.00 ± 0.13, P < 0.05). Conclusion:Exposure to fluoride can cause renal tissue injury in rats, with downregulation of SIRT3 and P62 expression levels, and upregulation of FOXO3a, PINK1, PARKIN, and LC3 expression levels.
