Studies on the reproductive, cytological and biochemical toxicity of Ginkgo biloba in Swiss albino mice

Ginkgo biloba (an herbal product), used as a folkloric medicine in the treatment of dementia, was evaluated for its effects on reproductive, cytological and biochemical toxicity in male Swiss albino mice. The mice were treated with different doses (25, 50 and 100 mg/kg/day) of the aqueous suspension of Ginkgo biloba for 90 days by oral gavage. The following parameters were evaluated: (1) reproductive organ weight; (2) motility and content of sperms; (3) spermatozoa morphology; (4) cytology of the testes chromosomes; (5) study on reproduction; (6) biochemical study on proteins, nucleic acids, malondialdehyde (MDA) and nonprotein sulfhydryl (NP-SH). The treatment caused significant changes in the weight of caudae epididymis, prostate, chromosomal aberrations, rate of pregnancy and pre-implantation loss. However, the percent motility, sperm count and morphology of spermatozoa were not affected. Our study on biochemical parameters showed depletion of nucleic acids, NP-SH and increase of MDA, which elucidated the role of free radical species in the induced changes in testis chromosomes and the reproductive function. The exact mechanism is not known, however, the activation of GABA, glycine and glutamate under the influence of Ginkgo biloba and its constituents might have generated free radicals and depleted cellular glutathione by calcium influx and membrane depolarization. The observed toxicity is attributed to the toxic constituents (ginkgolic acids, biflavones, cardanols, cardols, bilobalides and quercetin) of Ginkgo biloba. Our results warrant careful use of Ginkgo biloba as a remedy for impotence and/or erectile dysfunction. (c) 2006 Elsevier Ireland Ltd. All rights reserved.