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The sensitivity of male rat reproductive organs to monosodium glutamate
Sitthichai Iamsaard1, Wannisa Sukhorum, Rarinthorn Samrid
1Department of Anatomy, Faculty of Medicine, Khon Kaen University, 123 Mitraparp Road, Amphoe Muang, Khon Kaen 40002, Thailand. Iamsaard_sitt@yahoo.com, sittia@kku.ac.th.
Objective:
This study aimed to investigate the sensitivity of the testis, epididymis, seminal vesicle, and sperm acrosome reaction (AR) to monosodium L- glutamate (MSG) in rats.
Materials And Methods:
Rats were divided into four groups and fed with non-acidic MSG at 0.25, 3 or 6 g/kg body weight for 30 days or without MSG. The morphological changes in the reproductive organs were studied. The plasma testosterone level, epididymal sperm concentration, and sperm AR status were assayed.
Results:
Compared to the control, no significant changes were discerned in the morphology and weight of the testes, or the histological structures of epididymis, vas deferens and seminal vesicle. In contrast, significant decreases were detected in the weight of the epididymis, testosterone levels, and sperm concentration of rats treated with 6 g/kg body weight of MSG. The weight loss was evident in the seminal vesicle in MSG-administered rats. Moreover, rats treated with MSG 3 and 6 g/kg exhibited partial testicular damage, characterized by sloughing of spermatogenic cells into the seminiferous tubular lumen, and their plasma testosterone levels were significantly decreased. In the 6 g/kg MSG group, the sperm concentration was significantly decreased compared with the control or two lower dose MSG groups. In AR assays, there was no statistically significant difference between MSG-rats and normal rats.
Conclusion:
Testicular morphological changes, testosterone level, and sperm concentration were sensitive to high doses of MSG while the rate of AR was not affected. Therefore, the consumption of high dose MSG must be avoided because it may cause partial infertility in male.
Insights
High doses of monosodium L-glutamate (MSG) negatively impact male rat reproductive health, causing testicular damage and reduced sperm counts. However, sperm acrosome reaction (AR) remained unaffected by MSG exposure.
Area of Science:
- Reproductive toxicology
- Endocrinology
- Male reproductive system research
Background:
- Monosodium L-glutamate (MSG) is a widely used food additive.
- Potential adverse effects of high MSG consumption on male reproductive health require investigation.
Purpose of the Study:
- To evaluate the impact of varying monosodium L-glutamate (MSG) doses on male rat reproductive organs and sperm function.
- To determine the sensitivity of the testis, epididymis, seminal vesicle, and sperm acrosome reaction (AR) to MSG exposure.
Main Methods:
- Rats were administered non-acidic MSG at 0, 0.25, 3, or 6 g/kg body weight for 30 days.
- Evaluated were organ morphology, weight, plasma testosterone levels, epididymal sperm concentration, and sperm AR status.
Main Results:
- High MSG doses (3 and 6 g/kg) induced partial testicular damage and decreased seminal vesicle weight.
- Significant reductions in epididymis weight, testosterone levels, and sperm concentration were observed at 6 g/kg MSG.
- No significant changes were noted in testicular or epididymal morphology, histological structures, or sperm acrosome reaction (AR) rates.
Conclusions:
- Testicular morphology, testosterone levels, and sperm concentration are sensitive to high MSG doses.
- Sperm acrosome reaction (AR) rate is not significantly affected by MSG exposure.
- High MSG consumption should be avoided due to potential risks of partial male infertility.
