Aloe vera toxic effects: expression of inducible nitric oxide synthase (iNOS) in testis of Wistar rat

Document Type : Original Article


1 Department of Molecular Medicine, Faculty of Advanced Medical Technologies, Tehran University of Medical Sciences, Tehran, Iran

2 Medical Plant Research Center, Shahrekord University of Medical Sciences, Shahrekord, Iran

3 Cellular and Molecular Research Center, Shahrekord University of Medical Sciences, Shahrekord, Iran

4 Department of Genetics, Faculty of Basic Sciences, University of Shahrekord, Shahrekord, Iran


Objective(s): Nitric oxide (NO), a product of inducible nitric oxide synthase (iNOS), contributes in germ cell apoptosis. This study was aimed to evaluate the effects of Aloe vera gel (AVG) on male Wistar rat reproductive organ, serum NO level, and expression of iNOS gene in leydig cells.
Materials and Methods:Adult male Wistar rats (n=36) were used for experiments in three groups. The experimental groups were orally administered with the AVG extract solution once-daily as follow: 150; group A, 300; group B, and only normal saline; group C (control group). They were mated with untreated females and the reproductive and chemical parameters were assessed for each group, including semen quality, serum testosterone, sperm fertility, gonad and body weight, serum NO concentration (by the Griess method), and iNOS gene expression (using RT-PCR).
Results: The testes weight, serum testosterone, as well as sperm count and fertility of the AVG treated groups were significantly reduced when compared to the control (P<0.001). Concentration of serum NO was significantly increased (37.1±4.63 µM) in the administrated group with higher AVG concentration, compared to the control group (P<0.001; 10.19±0.87 µM); however, iNOS mRNA expression was increased in the treated animals (P<0.001).
Conclusion:iNOS may play a functional role in spermatogenesis via apoptosis, reducing sperm count, but further studies are needed to illustrate the mechanisms by which AVG exerts its negative effects on spermatogenesis and sperm quality.


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