[Myricetin reduces the reproductive toxicity of cyclophosphamide in male mice]

To explore the effect of myrica flavone on male reproductive toxicity induced by cyclophosphamide and its mechanism.

Thirty 6-week-old male ICR mice were randomly divided into 5 groups: blank control group, cyclophosphamide reproductive injury model group, myricetin low-medium high-dose intervention group. Except the blank control group, the other groups were intraperitoneally injected with cyclophosphamide 50 mg/kg daily for 7 consecutive days. The myricetin group received intragastric administration of 100, 200, and 400 mg/kg myricetin daily for 30 consecutive days since the second day of modeling. The blank control group and the model control group were given an equal volume of a 0. 25% sodium carboxymethyl cellulose solution. The body weight was measured every 3 days, and the day after the last administration, the mice were sacrificed by cervical dislocation, and the epididymis and testes were quickly taken. Testicular weighing, testicular index calculation, epididymis to obtain sperm, sperm analyzer to analyze sperm density and vitality. The expression of Bax and Bcl-2 in testicular tissues was detected by immunoblotting, and the mitochondrial membrane potential of sperm was detected by flow cytometry.

After 9 days of modeling, the weight of mice in the model group was lower than that of the blank control group, which was statistically different(P<0. 05). There was no difference between the myricetin treatment group and the model group. The testis index of the model group was(3. 93±0. 91)mg/g, which was significantly lower than that of the blank control group(6. 93±0. 98)mg/g, and the difference was statistically significant(P<0. 05). After treatment with bayberry flavonoids, the testis index increased, in the 100 and 200 groups and 400 mg/kg testis index were(3. 94±1. 21) mg/g, (4. 33±0. 88) mg/g, and(4. 80±0. 43) mg/g, respectively. Compared with model control group, The difference was statistically significant(P<0. 05 and P<0. 01). Compared with the control group, the sperm density, sperm rate of forward movement, sperm rate of non-forward movement, and decreased sperm rate of non-moving sperm increased in the model group. After treatment with bayberry flavonoids, compared with the model group, the sperm density, sperm rate of forward motion, and sperm rate of non-forward motion increased, and the immobility sperm rate decreased. The 200 and 400 mg/kg groups had statistical significance(P<0. 05 or P<0. 01); the normal rate of sperm mitochondrial membrane potential in the model group was(54. 70±5. 45)%, and the normal mitochondrial membrane potential rate after treatment with myricetin of 100, 200 and 400 mg/kg(59. 10±9. 97)%, (62. 10±6. 07)% and(77. 10±8. 87)%, of which the 400 mg/kg group was statistically significant(P<0. 05); the ratio of Bax/Bcl-2 in the model group was 5. 92±1. 45, and the ratio of Bax/Bcl-2 decreased after treatment with myricetin of 100, 200 and 400 mg/kg, which were 2. 52±0. 51, 1. 71±0. 52 and 1. 07±0. 29. There were statistical differences(P<0. 05 or P<0. 01).

Myrica flavone can protect sperm mitochondrial membrane potential, inhibit testicular cell apoptosis, and protect the male mice from reproductive toxicity induced by cyclophosphamide.