Effect of naringin on sodium fluoride induced neurobehavioral deficits in Wistar rats.

Discussion A fluoride concentration of 0.2 to 3.5 ppm is sufficient to induce dental fluorosis (2). According to the data published from 1990 to 2012, it has been reported that the prevalence of fluorosis in South Africa is 47%, while in Iran it is 61% (23). Approximately 82.4% of Sri Lanka's population lives in the low fluoride region with ~80% of children experiencing mild to severe forms of dental fluorosis (24). Intake of fluoride in an excessive amount above the safe limit is the chief

Abstract

There is a lack of treatment for the detrimental effects of fluorosis. Sodium fluoride at a concentration of 10 ppm induces stress, depression and memory impairment in adult Wistar rats. Naringin, a flavanone glycoside isolated from citrus fruits such as lemons and oranges, possesses anti?inflammatory, antioxidant and neuroprotective properties; therefore, it was used for treatment of fluoride induced toxicity in the present study. Adult Wistar rats were divided into eight groups (n=8). The normal control (NOR) group was provided with normal tap water. The sodium fluoride (FLU)10 group received water containing 10 ppm sodium fluoride for 60 days. The treatment groups (FLU10NAR100 and FLU10NAR50) received drinking water with 10 ppm sodium fluoride ad libitum along with Naringin 100 and 50 mg/kg body weight (bw) per oral gavage, respectively. The NAR100 and NAR50 groups received Naringin 100 and 50 mg/kg bw. The PRONAR100 and PRONAR50 groups received Naringin 100 and 50 mg/kg bw for the first 15 days and then subsequently received FLU10 ppm for 60 days (total of 75 days). All animals were subjected to behavioural tests consisting of the open field test (OFT), forced swim test (FST) and novel object recognition test (NORT). After euthanasia, the hippocampus and prefrontal cortex were stained with Cresyl violet. To measure the oxidative stress caused by fluoride and its effect on antioxidant levels, estimation of reduced glutathione (GSH) by Ellman’s method, lipid peroxidation (LPO) measured in terms of the MDA:thiobarbituric acid reaction and catalase was performed. To evaluate the effect of fluoride on activity of acetylcholine, estimation of acetylcholinesterase (AChE) by Ellman’s method was performed. In NORT and FST, significant changes (P<0.05) were present in the FLU10NAR100 and FLU10NAR50 groups compared with the FLU10 group, showing recovery from memory deficit and depression. The OFT results were insignificant. The LPO was reduced in all the other groups except the FLU10 group, with statistically significant changes. Catalase activity was significantly lower in FLU10 as compared with the NAR100, NAR50, PRONAR100 and PRONAR50 groups. GSH and AChE activities did not show significant changes as compared with the FLU10 group. The CA3 and prefrontal cortex viable and degenerated neuron count in the FLU10 group were insignificant compared with all other groups, except for the NAR100 and NAR50 groups. Thus, Naringin can be a useful drug to avoid the neurological effects of fluoride.

Full-text study online at https://www.spandidos-publications.com/10.3892/br.2024.1785

Excerpt:

Discussion

A fluoride concentration of 0.2 to 3.5 ppm is sufficient to induce dental fluorosis (2). According to the data published from 1990 to 2012, it has been reported that the prevalence of fluorosis in South Africa is 47%, while in Iran it is 61% (23). Approximately 82.4% of Sri Lanka’s population lives in the low fluoride region with ~80% of children experiencing mild to severe forms of dental fluorosis (24).

Intake of fluoride in an excessive amount above the safe limit is the chief cause of fluorosis and various neurological manifestations in the form of depression and decreased intelligence quotient (IQ), which has been observed in children (25,26). In Mexico, 132 children between the age group of 6 to 10 years from rural communities drink water that contains high fluoride content and thus exhibit reduced IQ scores (27). Fluoride concentrations from 1.2 to 3 ppm in drinking water have an inverse correlation with the IQ of 10-12-year-old children in Karnataka (26). Attention deficit hyperactivity disorder was observed at a higher rate in children aged 4 to 17 years in the United States of America in national surveys conducted in 2003, 2007 and 2011, where a greater portion of the population received fluoridated water (28)….