[Effects of L-carnitine on the apoptosis of spermatogenic cells and epididymal sperm count and motility in rats with diabetes mellitus].

OBJECTIVE:To explore the effects of L-carnitine (LC) on the apoptosis of spermatogenic cells and on the count and motility of epididymal sperm in rats with diabetes mellitus (DM). METHODS:Twenty-four SD rats (200-230 g) were randomly divided into a control group, a DM model group and an LC group. After the establishment of DM models in the latter two groups by injection of streptozotocin (STZ) at 65 mg/kg, the controls and DM models were treated intragastrically with physiological saline, while the rats in the LC group with LC at 300 mg/kg, all for 6 consecutive weeks. Twenty-four hours after the last administration, all the rats were killed for the detection of the count and motility of epididymal sperm and the apoptosis of spermatogenic cells. RESULTS:The motilities of caput and cauda epididymal sperm were (53.7 +/- 1.8)% and (60.3 +/- 1.6)% in the LC group, significantly higher than in the DM model group ([32.2 +/- 2.0]% and [40.5 +/- 1.4]%, P < 0.05), but remarkably lower than in the control ([63.1 +/- 2.4 ]% and [68.9 +/- 1.3]%, P < 0.05). The count of cauda epididymal sperm was (25.5 +/- 1.1) x 10(6)/100 mg in the DM models, and was increased to (32.0 +/- 1.5) x 10(6)/100 mg after LC treatment (P < 0.05), but still markedly lower than in the controls ([37.8 +/- 1.1] x 10(6)/100 mg) (P < 0.05). The apoptosis rate of spermatogenic cells was (52.5 +/- 4.4)% in the DM model group, and it was reduced to (35.3 +/- 3.5)% after LC administration (P < 0.05), but still significantly higher than in the control group ([3.7 +/- 1.3]%) (P < 0.05). CONCLUSION:Intragastrically gavage of LC at 300 mg/kg for 6 weeks increased the epididymal sperm count, improved sperm motility, and reduced the apoptosis of spermatogenic cells in rats with DM.