title: Combining a synthetic spermicide with a natural trichomonacide for safe, prophylactic contraception.
abstract: OBJECTIVE
  Can a specifically acting synthetic spermicide (DSE-37) be combined with a natural microbicide (saponins) for safe, prophylactic contraception?
  
  
  CONCLUSIONS
  A 1:1 (w/w) combination of DSE-37 and Sapindus saponins can target sperm and Trichomonas vaginalis precisely without any noticeable off-target effects on somatic cells at effective concentrations.
  
  
  BACKGROUND
  Broad-spectrum vaginal agents like nonoxynol-9 (N-9) and cellulose sulfate have failed clinically as microbicides due to non-specific off-target effects, whereas agents that specifically target retroviruses have shown promise in clinical trials. DSE-37 and Sapindus saponins, respectively, specifically target human sperm and T. vaginalis in vitro.
  
  
  METHODS
  A comprehensive study of efficacy and safety was undertaken using in vitro (human cells) and in vivo (rabbit) models. The 1:1 combination of DSE-37 and Sapindus saponins was based on the in vitro spermicidal and anti-Trichomonal activities of the two components. N-9, the spermicide in clinical use, served as reference control. Free sperm thiols were fluorescently glinted to reveal differences in the targets of the test agents.
  
  
  METHODS
  On/off-target effects were evaluated in vitro against human sperm, T. vaginalis, HeLa, Vk2/E6E7, End1/E6E7 and Lactobacillus jensenii, using standard assays of drug susceptibility, cell viability, flow cytometric assessment of cell apoptosis and qPCR for expression of pro-inflammatory cytokine mRNAs. The spermicidal effect was also recorded live and free thiols on sperm were fluorescently visualized using a commercial kit. In vivo contraceptive efficacy (pregnancy/fertility rates) and safety (vaginal histopathology and in situ immune-labeling of inflammation markers VCAM-1, E-selectin and NFkB) were evaluated in rabbits.
  
  
  RESULTS
  A 0.003% drug 'combination' containing 0.0015% each of DSE-37 and Sapindus saponins in physiological saline irreversibly immobilized 100% human sperm in ∼30 s and eliminated 100% T. vaginalis in 24 h, without causing any detectable toxicity to human cervical (HeLa) cells and Lactobacilli in 24-48 h, in vitro. N-9 at 0.003% exhibited lower microbicidal activity against Trichomonas but failed in spermicidal assays while causing severe toxicity to HeLa cells and Lactobacilli in 12-24 h. The 'combination' of DSE-37 and Sapindus saponins completely prevented pregnancy in rabbits at a vaginal dose of 20 mg (1% in K-Y Jelly), while application of 5% 'combination' in K-Y Jelly for 4 consecutive days caused negligible alterations in epithelial lining of rabbit vagina with only minor changes in levels of inflammation markers. N-9 at a 20 mg vaginal dose prevented pregnancy in 33% animals and a 4-day repeat application of 2% N-9 gel caused severe local toxicity to vaginal epithelium with molecular expression of acute inflammation markers.
  
  
  CONCLUSIONS
  The number of animals used for the in vivo efficacy study was limited by the approval of the animal ethics committee.
  
  
  CONCLUSIONS
  Anti-Trichomonal contraceptives with specifically acting synthetic component and clinically-proven safe natural component may define a new concept in empowering women to control their fertility and reproductive health.
  
  
  BACKGROUND
  The study was funded by CSIR-Network Project 'PROGRAM' (BSC0101) and partly by the Ministry of Health and Family Welfare, Government of India (GAP0001). The funding agencies did not play any role in this study and none of the authors had any competing interest(s).
authors.affiliation: Division of Endocrinology, CSIR-Central Drug Research Institute, Lucknow 226031, India.
authors.forename: Ashish
authors.initials: A
authors.lastname: Jain
authors.forename: Lokesh
authors.initials: L
authors.lastname: Kumar
authors.forename: Bhavana
authors.initials: B
authors.lastname: Kushwaha
authors.forename: Monika
authors.initials: M
authors.lastname: Sharma
authors.forename: Aastha
authors.initials: A
authors.lastname: Pandey
authors.forename: Vikas
authors.initials: V
authors.lastname: Verma
authors.forename: Vikas
authors.initials: V
authors.lastname: Sharma
authors.forename: Vishal
authors.initials: V
authors.lastname: Singh
authors.forename: Tara
authors.initials: T
authors.lastname: Rawat
authors.forename: Vishnu L
authors.initials: VL
authors.lastname: Sharma
authors.forename: Jagdamba P
authors.initials: JP
authors.lastname: Maikhuri
authors.forename: Gopal
authors.initials: G
authors.lastname: Gupta
mesh_terms: D000634:Aminoquinolines / Q000737:chemistry*; D000818:Animals; D000890:Anti-Infective Agents / Q000008:administration & dosage*; D003270:Contraceptive Agents / Q000627:therapeutic use*; D004220:Disulfides / Q000737:chemistry; D005260:Female; D006367:HeLa Cells; D006801:Humans; D007249:Inflammation; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008297:Male; D053078:Membrane Potential, Mitochondrial; D010590:Phalloidine / Q000737:chemistry; D011817:Rabbits; D032127:Sapindus / Q000378:metabolism; D012661:Semen / Q000187:drug effects; D013089:Spermatocidal Agents / Q000008:administration & dosage*; D013094:Spermatozoa / Q000473:pathology; D013500:Surface Tension; D013501:Surface-Active Agents / Q000737:chemistry; D014246:Trichomonas vaginalis / Q000378:metabolism
chemical_list: D000634:Aminoquinolines; D000890:Anti-Infective Agents; D003270:Contraceptive Agents; C519274:DSE-37 compound; D004220:Disulfides; D013089:Spermatocidal Agents; D013501:Surface-Active Agents; D010590:Phalloidine; C035138:trichomonacid; D007770:L-Lactate Dehydrogenase
keywords: DSE-37; Sapindus saponins; Trichomonas vaginalis; spermicide; vaginal contraception