The therapeutic and protective effects of bee pollen against prenatal methylmercury induced neurotoxicity in rat pups

  • Abir Ben BachaEmail author
  • Al-Orf Norah
  • May Al-Osaimi
  • Abdel Halim Harrath
  • Lamjed Mansour
  • Afaf El-Ansary
Original Article


The current study evaluated the protective and therapeutic potency of bee pollen in ameliorating the toxic effects of methylmercury (MeHg), by measuring certain biochemical parameters related to neurotransmission, neuroinflammation, apoptosis, and glutamate excitotoxicity in the male neonate brain. Healthy, pregnant female rats (N = 40) were randomly divided into 5 groups, each comprising10 male neonates, as follows: (i) neonates delivered by control mothers; (ii) neonates delivered by MeHg-treated mothers who received 0.5 mg/kg BW/day MeHg via drinking water from gestational day 7 till postnatal day 7; (iii) neonates delivered by bee pollen treated mothers who received 200-mg/kg BW bee pollen from postnatal day 0 for 4 weeks; (iv) protective group of neonates delivered by MeHg and bee pollen-treated mothers, who continued to receive bee pollen until day 21 at the same dose, and (v) therapeutic group of neonates delivered by MeHg- treated mothers followed by bee pollen treatment, wherein they received 200-mg/kg BW bee pollen from postnatal day 0 for 4 weeks. Selected biochemical parameters in brain homogenates from each group were measured. MeHg-treated groups exhibited various signs of brain toxicity, such as a marked reduction in neurotransmitters (serotonin (5-HT), nor-adrenalin (NA), dopamine (DA)) and gamma aminobutyric acid (GABA) and elevated levels of interferon gamma (IFN-γ), caspase-3, and glutamate (Glu). Bee pollen effectively reduced the neurotoxic effects of MeHg. Minimal changes in all measured parameters were observed in MeHg-treated animals compared to the control group. Therefore, bee pollen may safely improve neurotransmitter defects, inflammation, apoptosis, and glutamate excitotoxicity.


Autism Methylmercury Bee pollen Neurotransmitters Interferon gamma Caspase-3 And glutamate excitotoxicity 





one-way analysis of variance


amyloid precursor protein


area under the curve

amyloid beta


blood brain barrier


center nerves system








gamma aminobutyric acid










interferon gamma




nuclear factor kappa light chain enhancer of activated B cells




receiver operating characteristics curve


standard deviation



This work was financed by Researchers Supporting Project number (RSP-2019/17), King Saud University, Riyadh, Saudi Arabia.

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 animals were in accordance with the ethical standards of the institution or practice at the Faculty of King Saud University (KSU-SE-17-10).


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Authors and Affiliations

  • Abir Ben Bacha
    • 1
    • 2
    Email author
  • Al-Orf Norah
    • 1
    • 3
  • May Al-Osaimi
    • 1
  • Abdel Halim Harrath
    • 4
  • Lamjed Mansour
    • 4
  • Afaf El-Ansary
    • 5
  1. 1.Biochemistry Department, Science CollegeKing Saud UniversityRiyadhSaudi Arabia
  2. 2.Laboratory of Plant Biotechnology Applied to Crop Improvement, Faculty of Science of SfaxUniversity of SfaxSfaxTunisia
  3. 3.The Materials Science Research InstituteKing Abdulaziz City for Science and TechnologyRiyadhSaudi Arabia
  4. 4.Department of Zoology, College of ScienceKing Saud UniversityRiyadhSaudi Arabia
  5. 5.Central LaboratoryKing Saud UniversityRiyadhSaudi Arabia

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