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Chronic Fluoride Exposure Disrupts Calcium-Dependent Neurodevelopmental Signalling and Brain Proteomic Architecture: Multi-Target Modulation by Naringin.
| Biological Trace Element Research | Swamy RS, Choudhary S, Ambawatiya A, Chhabra V, Mishra M, Abubakar M, Shenoy S, Kumar N, Gajbhiye RL, Rai A, Ravichandiran V, Kumar N. | Online ahead of print.
mitochondrial dysfunction Naringin Protective effect Behavior Brain Neurodevelopmental Oxidative Stress Animal Study

Abstract

Original abstract online at
https://link.springer.com/article/10.1007/s12011-026-05250-y

Long-term exposure to fluoride during early development is associated with impairments in neurobehavioral functions, oxidative stress, and molecular alterations in the developing brain. However, the mechanisms by which fluoride disrupts neurodevelopment, as well as the potential of natural flavonoids such as naringin to counteract these effects, are not well characterised. This study aimed to investigate the neurodevelopmental harms of fluoride and evaluate the multi-target neuroprotective efficacy of naringin using behavioural, biochemical, antioxidant, proteomic, and gene expression approaches in rats. Adult male and female Wistar rats and their offspring were exposed to sodium fluoride with or without naringin throughout development. Neurodevelopmental and behavioural assessments were performed along with estimation of serum and urine fluoride levels. Brain oxidative stress markers and biochemical parameters were analysed, followed by proteomic profiling (LC–MS/MS), functional enrichment analysis, and PCR validation of selected molecular markers. Fluoride exposure did not significantly affect most neonatal reflexes but produced selective impairments in specific sensorimotor parameters and pronounced behavioural deficits during post-weaning stages. Rats exposed to fluoride exhibited increased oxidative stress, altered antioxidant enzyme activities, and elevated fluoride levels in both serum and urine, highlighting systemic and neuronal toxicity. Proteomic analysis indicated a dysregulation of pathways linked to mitochondrial function, calcium signalling (including pathways associated with CALM2), synaptic plasticity, and apoptosis. PCR analysis confirmed alterations in key neuronal and stress-related genes. Co-treatment with naringin significantly alleviated behavioural impairments, restored antioxidant balance, reduced fluoride accumulation, mitigated dysregulation across multiple molecular pathways, and lessened changes in both proteomic and transcriptional markers. Fluoride exposure was associated with neurodevelopmental toxicity involving oxidative imbalance, mitochondrial dysfunction, calcium-related signalling disturbances, and alterations in synaptic pathways. Naringin attenuated many behavioural, biochemical, and molecular alterations, indicating a protective effect across multiple targets. These findings support further investigation of naringin as a potential protective compound against fluoride-induced neurodevelopmental alterations.

Data Availability

The datasets generated and/or analysed during the current study are available from the corresponding author on reasonable request.

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Acknowledgements

The authors are grateful to the Indian Council of Medical Research, India, for providing extramural funding for this project.

Funding

We thank ICMR for providing extramural funding for the project (Grant Number: 5/8–4/6/Env/2020-NCD-II), P.I. Dr Nitesh Kumar, Co-PIs: Dr. Ravindra Shantakumar Swamy, Dr. Smita Shenoy and Dr. Velayutham Ravichandiran.

Author information

Author notes

  1. Ravindra Shantakumar Swamy, Shalini Choudhary and Abhishek Ambawatiya contributed equally to this work.

Authors and Affiliations

  1. Department of Basic Medical Sciences, Manipal Academy of Higher Education, Manipal, 576 104, Karnataka, India

    Ravindra Shantakumar Swamy

  2. Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research, Hajipur, Vaishali, Bihar, 844102, India

    Shalini Choudhary, Abhishek Ambawatiya, Vishal Chhabra, Mayank Mishra, Md Abubakar, Velayutham Ravichandiran & Nitesh Kumar

  3. Department of Pharmacology, Kasturba Medical College, Manipal Academy of Higher Education, Manipal, 576 104, Karnataka, India

    Smita Shenoy

  4. Department of Anatomy, RAK College of Medical Sciences, RAK Medical and Health Sciences University (RAKMHSU), Ras Al Khaimah, 11172, UAE

    Naveen Kumar

  5. Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research, Hajipur, Vaishali, Bihar, 844102, India

    Rahul L. Gajbhiye, Amita Rai & Velayutham Ravichandiran

  6. Delhi Pharmaceutical Sciences and Research University, New Delhi, India

    Velayutham Ravichandiran

Contributions

Conceptualisation, Project administration : Ravindra Shantakumar Swami, Nitesh Kumar; Review and editing of manuscript : Shalini Choudhary, Abhishek Ambawatiya Vishal Chhabra, Ravindra Shantakumar Swamy, Nitesh Kumar, Naveen Kumar; Investigation, Interpretation – Ravindra Shantakumar Swami, Md Abubakar, Abhishek Ambawatiya, Rahul L. Gajbhiye, Mayank Mishra, Vishal Chhabra; writing original draft: Shalini Choudhary, Abhishek Ambawatiya, Vishal Chhabra, Smita Shenoy, Amita Rai, Supervision : Velayutham Ravichandiran, Krishna Murti, Smita Shenoy, Nitesh Kumar. All authors reviewed and approved the final manuscript.

Corresponding author

Correspondence to Nitesh Kumar.

Ethics declarations

Ethical Approval

All animal experimental procedures were conducted in accordance with the guidelines of the Committee for Control and Supervision of Experiments on Animals (CCSEA), Government of India. The experimental protocol was reviewed and approved by the Institutional Animal Ethics Committee (IAEC) with approval no. IAEC/KMC/62/2019.

Ethical Standards

All procedures performed in studies involving animals were conducted in accordance with institutional guidelines and national regulations for the care and use of laboratory animals.

Consent for Publication

All authors have given their consent for Publication. The manuscript does not contain any person’s data in any form.

Competing Interests

The authors declare no competing interests.

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