N,N'–Dithiobisphthalimide, a disulfide aromatic compound, is a potent spermicide agent in humans

Abstract

Several studies have shown that users of vaginal preparations containing nonoxynol-9 (N-9) are at a high risk for sexually transmitted diseases, including HIV. Therefore, there is a great interest in identifying compounds that can specifically inhibit sperm without damaging the vaginal lining, possess a powerful spermicide activity, and can be used in contraceptive vaginal preparations to replace N-9. In this work, we studied the spermostatic and/or spermicidal activity of five non-detergent, disulfide compounds on human sperm, HeLa cells, and Lactobacillus acidophilus. The motility and viability of human sperm in semen and culture medium was evaluated after treatment with different concentrations of the disulfide compounds (2.5 -100 µM). In addition, we evaluated the cytotoxic effect on HeLa cells and L. acidophilus. We identified compound 101, N, N , as the most effective molecule. It has a half maximal effective concentration (EC 50 ) of 8 µM and a minimum effective concentration (defined as the concentration that immobilizes 100 percent of the sperm in 20 sec) of 24 µM. At these concentrations, compound 101 does not affect the viability of the sperm, HeLa cells, or L. acidophilus. Our results indicate that dithiobisphthalimide has a potent spermostatic, irreversible effect with no toxic effects on HeLa cells and L. acidophilus.

Vaginal Administration of Contraceptives

“…Although the primary function of N-9 is to prevent pregnancy, it is an effective barrier against STDs, including gonorrhea, chlamydia1 infection candidiasis, syphilis, genital herpes, trichomoniasis, and the acquired immunodeficiency syndrome [100][101][102]. However, because of the strong surfactant action of N-9, it often disrupts the vaginal mucosa [103] and targets other cells in the vagina, such as the cervicovaginal epithelia that are essential for maintaining a natural barrier to pathogen invasion, especially HIV [104,105]. Thus, N-9 causes an acute tissue inflammatory response, increasing the risk of STDs such as HIV [106,107].…”

Espermicida y espermiostático: ¿hacen referencia a lo mismo?

“…El sufijo CIDA significa matador o exterminador y en el contexto biológico hace referencia a sustancias que producen muerte a organismos vivos, por ejemplo hongos -fungicida-, insectos -insecticida-o hierbas -herbicida-(7). Se ha encontrado que algunos compuestos considerados espermicidas no causan necesariamente la muerte de los espermatozoides, sólo su inmovilización (8,9), lo que en realidad acuñaría el término espermiostático, sin embargo el tér-mino espermicida se utiliza comúnmente y sin distinción entre muerte o inmovilización espermática.…”