Metabolic Brain Disease

, Volume 31, Issue 3, pp 593–599 | Cite as

The levels of blood mercury and inflammatory-related neuropeptides in the serum are correlated in children with autism spectrum disorder

  • Gehan Ahmed MostafaEmail author
  • Geir Bjørklund
  • Mauricio A. Urbina
  • Laila Yousef AL-Ayadhi
Original Article


Tachykinins (substance P, neurokinin A, and neurokinin B) are pro-inflammatory neuropeptides that may play an important role in some autoimmune neuroinflammatory diseases, including autism spectrum disorder (ASD). Mercury (Hg) is a neurotoxicant, and potentially one of the main environmental triggers for ASD as it induces neuroinflammation with a subsequent release of neuropeptides. This is the first study to explore the potentially causal relationship between levels of serum neurokinin A and blood mercury (BHg) in children with ASD. Levels of serum neurokinin A and BHg were measured in 84 children with ASD, aged between 3 and 10 years, and 84 healthy-matched children. There was a positive linear relationship between the Childhood Autism Rating Scale (CARS) and both serum neurokinin A and BHg. ASD children had significantly higher levels of serum neurokinin A than healthy controls (P < 0.001). Increased levels of serum neurokinin A and BHg were respectively found in 54.8 % and 42.9 % of the two groups. There was significant and positive linear relationship between levels of serum neurokinin A and BHg in children with moderate and severe ASD, but not in healthy control children. It was found that 78.3 % of the ASD patients with increased serum levels of neurokinin A had elevated BHg levels (P < 0.001). Neuroinflammation, with increased levels of neurokinin A, is seen in some children with ASD, and may be caused by elevated BHg levels. Further research is recommended to determine the pathogenic role of increased levels of serum neurokinin A and BHg in ASD. The therapeutic role of tachykinin receptor antagonists, a potential new class of anti-inflammatory medications, and Hg chelators, should also be studied in ASD.


Autism Neurokinin A Neuroinflammation Mercury 



This research project was supported by a grant from the Research Center of the Center for Female Scientific and Medical Colleges, Deanship of Scientific Research, King Saud University.

Compliance with ethical standards

Conflict of interest

The authors declare no potential conflicts of interest with respect to the authorship, and/or publication of this article.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.


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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  1. 1.Department of Pediatrics, Faculty of MedicineAin Shams UniversityCairoEgypt
  2. 2.Autism Research and Treatment Center, AL-Amodi Autism Research Chair, Department of Physiology, Faculty of MedicineKing Saud UniversityRiyadhSaudi Arabia
  3. 3.Council for Nutritional and Environmental MedicineMo i RanaNorway
  4. 4.Department of Biosciences, College of Life and Environmental SciencesUniversity of ExeterExeterUK
  5. 5.Departamento de Zoología, Facultad de Ciencias Naturales y OceanográficasUniversidad de ConcepciónConcepciónChile

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