Reproductive toxicity to male mice of nose only exposure to water- pipe smoke.

Background/aims: Water-pipe smoking (WPS) is popular in the Middle East and is starting to gain popularity in several Western countries as well. It is widely and erroneously perceived to be less harmful than other forms of tobacco use. The reproductive adverse effects of cigarette smoking have been studied before with conflicting results, but data on the possible adverse reproductive effects of WPS are lacking. Here, we assessed the effects of nose-only exposure to mainstream WPS generated by commercially available honey-flavored "moasel" tobacco in mice.

Methods: The duration of the session was 30 min/day for one month. Control mice were exposed to air. Twenty-four h after the last exposure, mice were killed and the testes and plasma removed for analysis. In testicular homogenates total protein, alkaline phosphatase activity, several indices of oxidative damage and Vascular Endothelial Growth Factor Receptor 2 (VEGFR2) were quantified. The plasma concentrations of leptin, testosterone, estrogen and luteinizing hormone (LH) were also measured. Histological analysis of testes and lungs was also conducted.

Results: WPS caused statistically significant decreases in the plasma concentrations of leptin, testosterone, and LH, and in the concentrations of total protein and the antioxidant indices measured. A statistically non-significant decrease in VEGFR2 protein in the WPS--exposed mice compared to the control mice was also found. The body and testicular weights of mice exposed to WPS, as well as their testicular alkaline phosphatase activity and light microscopic histology, and plasma estrogen concentration were all not significantly affected by WPS.

Conclusion: Further studies on the functional implications of these findings in mice exposed to WPS for longer durations are warranted.