Abstract

Fluoride is usually found in groundwater at a very wide range of concentration between 0.5 and 25 ppm. At present, few studies have assessed the renal effects of fluoride at environmentally relevant concentrations. Furthermore, most of these studies have used insensitive and nonspecific biomarkers of kidney injury. The aim of this study was to use early and sensitive biomarkers to evaluate kidney injury after fluoride exposure to environmentally relevant concentrations. Recently weaned male Wistar rats were exposed to low (15 ppm) and high (50 ppm) fluoride concentrations in drinking water for a period of 40 days. At the end of the exposure period, kidney injury biomarkers were measured in urine and renal mRNA expression levels were assessed by real time RT-PCR. Our results showed that the urinary kidney injury molecule (Kim-1), clusterin (Clu), osteopontin (OPN) and heat shock protein 72 excretion rate significantly increased in the group exposed to the high fluoride concentration. Accordingly, fluoride exposure increased renal Kim-1, Clu and OPN mRNA expression levels. Moreover, there was a significant dose-dependent increase in urinary B-2-microglobulin and cystatin-C excretion rate. Additionally, a tendency towards a dose dependent increase of tubular damage in the histopathological light microscopy findings confirmed the preferential impact of fluoride on the tubular structure. All of these changes occurred at early stages in which, the renal function was not altered. In conclusion using early and sensitive biomarkers of kidney injury, we were able to found proximal tubular alterations in rats sub-chronically exposed to fluoride.

• Related Studies :

  • Fluoridation of drinking water and chronic kidney disease: absence of evidence is not evidence of absence.

    Comment on Effects of fluoridation of community water supplies for people with chronic kidney disease. [Nephrol Dial Transplant. 2007, Oct;22(10):2763-7.] Sir, Ludlow et al. [1] only confirmed that our knowledge of the potential adverse effects of chronic low fluoride supplementation of drinking water on normal or diseased kidneys is insufficient. More than

  • Role of Some Natural Antioxidants in the Modulation of Some Proteins Expressions against Sodium Fluoride-Induced Renal Injury.

    Background: The aim of the present work is to find the effects of N-acetylcysteine (NAC) and/or thymoquinone (THQ) in the protection against acute renal injury induced by sodium fluoride (NaF). Method: Rats were distributed into five groups: G1 was normal (control), G2 was intoxicated with 10mg/kg NaF i.p., G3 was treated

  • A quantitative analysis of chronic exposure of selected heavy metals in a model diet in a CKD hotspot in Sri Lanka.

    Background Evidence of chronic low levels of exposure to heavy metals in Sri Lanka has emerged in a number of studies carried out in the recent past. The source and magnitude of such exposures have to be understood in order to assess the risk of adverse health effects of this exposure

  • Study of children drinking fluoridated and nonfluoridated water

    A special study was made of the quantitative excretion of albumin, red blood cells, and casts in 12-hour urine specimens in 12-year-old boys as part of the long-term study of children in the Newburgh-Kingston caries fluorine study. The objective of this study was to determine whether any irritative efIects on

  • Sodium fluoride induces apoptosis in the kidney of rats through caspase-mediated pathways and DNA damage

    Long-term excessive sodium fluoride (NaF) intake can cause many bone diseases and nonskeletal fluorosis. The kidneys are the primary organs involved in the excretion and retention of NaF. The objective of the present study was to determine the effects of NaF treatment on renal cell apoptosis, DNA damage, and the

• Related FAN Content :

  • Fluoride as a Cause of Kidney Disease in Humans

    Because the kidney is exposed to higher concentrations of fluoride than all other soft tissues (with the exception of the pineal gland), there is concern that excess fluoride exposure may contribute to kidney disease - thus initiating a "vicious cycle" where the damaged kidneys increase the accumulation of fluoride, causing

  • Fluoride as a Cause of Kidney Disease in Animals

    Because the kidney is exposed to higher concentrations of fluoride than all other soft tissues (with the exception of the pineal gland), there is concern that excess fluoride exposure may contribute to kidney disease - thus initiating a "vicious cycle" where the damaged kidneys increase the accumulation of fluoride, causing in

  • Kidney: A potential target for fluoride toxicity

    The kidneys are the organ responsible for clearing fluoride from the body. In the process of doing so, the kidneys are exposed to concentrations of fluoride that exceed, by a factor of 50, the concentration of fluoride in human blood. As such, the kidney have long been considered a potential

  • Fluoride & Kidney Stones

    It has long been suspected that fluoride may contribute to the formation of kidney stones. This suspicion has recently gained support from a study of an American man with skeletal fluorosis. According to the authors: "A new, important, medical problem (that seemed temporally related to cessation of fluoride exposure and subsequent negative calcium

  • Fluoride Gels & Kidney Function

    Scientists have found that the application of "Fluoride Gels" at the dental office causes very high spikes in the blood fluoride level. The high spikes in blood fluoride levels are a result of three factors: the high concentration of fluoride in the gel (= 12.3 mg of fluoride in each