OBJECTIVETo study the effects of Wuzi Yanzong Pills (WYP) on sperm mitochondrial membrane potential (MMP) and its ultrastructure in oligo-asthenozoospermia model rats.

METHODSOligo-asthenozoospermia models were made in 50 male rats weighing 200 - 220 g by intragastric administration of Tripterygium Glucosides at 30 mg per kg per d for 8 weeks, and then equally allocated to a model control, a Huangjing Zanyu Capsule (HZC) control, a low-dose WYP, a medium-dose WYP, and a high-dose WYP group. Another 10 age-matched normal male rats were included as normal controls. The rats in the model and normal control groups were given intragastrically distilled water at 10 ml/kg, those in the HZC group administered HZC at 3.01 g/kg, and those in the low-, medium- and high-dose WYP groups medicated with WYP at 2.30, 4.60 and 9.20 g/kg, respectively, once daily for 30 days. At 30 minutes after the last administration, we detected the sperm MMP by JC-1 fluorescent staining and flow cytometry, and examined the sperm ultrastructure under the JEM-1230 transmission electron microscope.

RESULTSJC-1 + % and its fluorescence intensity were (33.77 +/- 6.19)% and 1 468 +/- 496 in the model control, (56.34 +/- 10.35)% and 3 277 +/- 895 in the HZC control, (40.80 +/- 10.40)% and 2 016 +/- 767 in the low-dose WYP, (59.40 +/- 6.51)% and 3 897 +/- 643 in the medium-dose WYP, and (60.71 +/- 7.81)% and 3 371 +/- 647 in the high-dose WYP group, significantly reduced in comparison with (70.80 +/- 4.92)% and 4 360 +/- 945 in the normal control group (P < 0.05), but remarkably higher in the medium- and high-dose WYP groups than in the model controls (P < 0. 05). After modeling, the sperm membrane was loose and degenerated, the mitochondria swelling, variously sized and with incomplete membrane, and the axonemal structure unclear or ruptured. After 30 days of WYP administration, compared with the model control group, the rats exhibited integrated sperm membrane and mitochondrial membrane, reduced mitochondrial swelling and basically normal axonemal and microtubular structures.

CONCLUSIONTripterygium Glucosides could decrease the sperm mitochondrial membrane potential and damage the mitochondrial structure, while WYP could significantly increase the sperm mitochondrial membrane potential and reduce the sperm mitochondrial structure damage. The protection of the integrity of sperm mitochondrial structure and function is one of the mechanisms of WYP acting on oligo-asthenozoospermia.