A STUDY OF CHRONIC TOBACCO SHISHA SMOKE EXPOSURE ON SOME REPRODUCTIVE PARAMETERS AND SPERM DNA INTEGRITY IN ADULT MALE WISTAR RATS

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Department of Medicine

ABSTRACT
Currently there are no putative empirical data on the effect of Shishasmoking on sperm DNA integrity and some of the available data on the adverse effects of Shishasmoking on conventional semen characteristics: sperm count, sperm motility, sperm viability and sperm morphology are contradictory. Despite the well-known deleterious reproductive effects of cigarette smoking, it is relatively unclear whether or notShishasmoking has the same effect on male reproductive parameters. The present study was aimed at determining the effect of chronic Shishasmoke exposure on testicular and prostate gland parameters, and sperm DNA integrity in adult male Wistar rats. Twenty-one adult male Wistar rats between the ages of 8-12 weeks, weighing between 160 -180 g were divided by simple random into three groups containing 7 rats per group. Group I rats were kept for 30 minutes daily in the nose-only exposure chamber for a period 13 weeks without exposure to Shisha smoke; group II (with water in the Shishajar) was exposed to bonged shisha smoke (BSS) and group III (without water in the shisha jar) was exposed to unbonged Shishasmoke (UBSS), respectively for 7 seconds first and fresh air later for 53 seconds, alternatively for 30 minutes daily for a period of 13 weeks. The Shishasmoke was drawn from the Shishaapparatus outlet by a vacuum compressor at a pressure of 300 kPa into the nose-only exposure chamber where the rats were kept. At the end of the exposure, five animals from each group were randomly selected and anaesthetised with 0.4 mL/100g of combined ketamine and diazepam and blood samples were obtained through cardiac puncture. The result obtained showed that chronic exposure to Shishasmoke revealed a significant increase in testicular malondialdehyde(MDA) level, high sperm DNA fragmentation, marked reduction in serum testosterone concentration, sperm count and progressive sperm motility,pronounced necrosis of tissues in the seminiferous tubules in the testicular histology, intense necrosis and decreased epithelia heights in the prostate gland histological, abnormal sperm cell morphology, and increased serum prostate specific antigen (PSA) concentration were also recorded. The testicular MDA level in the BSS (1.61 ± 0.08 μmol/mg) groupwas significantly higher than the UBSS (1.26 ± 0.04 μmol/mg)and the control (0.44 ± 0.08 μmol/mg) groups. SerumPSA concentration in the BSS exposed group (3.04 ± 0.03 ng/ml) was significantly higher than the UBSS (1.94 ± 0.06 ng/ml) and the control (1.30 ± 0.05 ng/ml) groups. Serum testosterone concentration was considerably lower in the BSS group with value of 25.4 ± 1.16 nmol/L compared to UBSS (31.8 ± 0.58 nmol/L) and control(41.6 ± 0.50 nmol/L) groups. The DNA fragmentation index(DFI) resultsobtained were significantly higher in the BSS (29.0 ± 1.90%) and UBSS(20.0 ± 0.94%) exposed groupsthan the control group (9.6 ± 0.67%). Epididymal sperm counts were significantly lower in the BSS (3.3 ± 0.13 x107cell/ml) and UBSS (4.08 ± 0.08 x107 cell/ml) groups than the controlgroup(5.62 ± 0.15 x107 cell/ml). Progressive spermmotility percentage value in the BSS (32.2 ± 1.01%) exposed group was significantly lower than the UBSS (40.0 ± 1.70%) and the control (48.0 ± 2.50%) groups. Thenon-progressive sperm motility percentage values were higher in the BSS (47.0 ± 2.30%) and UBSS (43.6 ± 0.90%) exposed groups than the control group (37.0 ± 3.0%), non-motile sperm cell percentage values were higher in the exposed groups with values of21.4 ± 2.50% and 18.04 ± 1.40% for BSS and UBSS groups, respectively than the control (15.0 ± 2.23%) group.A significant (r = -0.904; P < 0.01) negative correlation was observed between malondialdehyde and testosterone concentration, and sperm count.While,a significant (r = 0.881; P < 0.01) positive correlation was observed between malondialdehyde and sperm DNA fragmentation index; serum testosterone concentration and sperm count (r = 0.939; P < 0.01); and significant negative correlation (r = -0.922; P < 0.01)between sperm DNA fragmentation index and sperm count.. The present study observed significant harmful effects of Shisha smoking in the testis and prostate gland of the experimental animals as evidenced by the histological damages in these organs. The study also highlighted the possible role of oxidative stress on the adverse effects of Shisha smoking on sperm count, motility, morphology and enhanced sperm DNA fragmentation in the Shisha exposed groups, which were higher in the bonged group. Shisha tobacco smoking as an alternate to the traditional cigarette smoking should be discouraged as the acclaimed less harmful method of smoking does not significantly remove the toxins in the smoke, but rather compounds the harmful effect of tobacco.