Hyperosmolar sexual lubricant causes epithelial damage in the distal colon: potential implication for HIV transmission.
BACKGROUND
Many sexual lubricants are hyperosmolar. Hyperosmolar enemas induce epithelial damage, and enema use has been associated with an increased risk of HIV infection. To inform the development of rectal microbicide formulation, we evaluated the effects of hyperosmolar gels on the rectal mucosa.


METHODS
Two commercial lubricants were compounded into iso-osmolar and hyperosmolar mixtures (283 and 3429 mOsm/kg, respectively). Each gel was radiolabeled with 500 micro Ci of (99m)Technetium-diethylene triaminepentaacetic acid, and 10 mL was given rectally to 10 subjects in random sequence. Sigmoidoscopy by an endoscopist blinded to treatment assignment was performed 90 min later to obtain luminal and mucosal samples. Urine radiolabel detection was used to assess mucosal permeability.


RESULTS
Epithelial denudation 10 cm from the anus occurred to a greater degree with the hyperosmolar gel than with the iso-osmolar formulation (median toxicity grade, 2.50 vs. 1.17 out of 3, respectively; P=.009). The hyperosmolar gel was also associated with lower isotope luminal concentration at 10 cm, compared with the iso-osmolar gel (median, 8.9% vs. 54.6% of administered concentration, respectively). Mucosal permeability measured through 12 h was reduced with the hyperosmolar gel (P=.037).


CONCLUSIONS
Rectally applied hyperosmolar gels induce greater epithelial denudation and luminal secretion than iso-osmolar gels. Because denudation plausibly increases the risk of HIV transmission, hyperosmolar gels make poor rectal microbicide formulations, and hyperosmolar sexual lubricants may increase susceptibility to HIV infection.
Fuchs
Edward J
EJ
Division of Clinical Pharmacology, Johns Hopkins University School of Medicine, Baltimore, MD 21287-5554 , USA. ejfuchs@jhmi.edu
Lee
Linda A
LA
Torbenson
Michael S
MS
Parsons
Teresa L
TL
Bakshi
Rahul P
RP
Guidos
Anita M
AM
Wahl
Richard L
RL
Hendrix
Craig W
CW
D003106:Colon / Q000187:drug effects* / Q000473:pathology*; D018592:Cross-Over Studies; D005782:Gels / Q000008:administration & dosage / Q000009:adverse effects* / Q000737:chemistry*; D015658:HIV Infections / Q000635:transmission*; D006801:Humans; D007413:Intestinal Mucosa / Q000187:drug effects* / Q000473:pathology*; D008153:Lubrication; D008297:Male; D009994:Osmolar Concentration; D012812:Sigmoidoscopy / Q000009:adverse effects
D005782:Gels