Background
1,25(OH)2D3/vitamin D3 receptor (VD3/VDR) signaling pathway can inhibit the occurrence of breast cancer in many ways. We used vitamin D3 to interfere with Hyperplasia of mammary glands (HMG) model rats, and to explore the intervention effect of vitamin D3 on HMG.
Conclusions
Supplementation of VD3 could markedly decrease the mammary gland thickness, nipple diameter, and nipple height of rats, accompanied by the decrease of serum E2, T, and LH. Intervention with VD3 can lead to decreased expression of ERa and PR, in conjunction with the increase of VDR.
Methods
We divided 42 female rats into six groups randomly: blank control group, hyperplasia model group, negative control group, and vitamin D3 (VD3) groups of low-dose (LVD, 5 µg/kg), medium-dose (MVD, 10 µg/kg), and high-dose (HVD, 20 µg/kg). We established HMG model in all groups except for the blank control group, then different dose of VD3 was intraperitoneal injected for VD3 groups and normal saline (NS) was given to the negative control group. After the experiment, the body weights, heights and diameters of nipples, and the thickness of the mammary gland of rats were measured. The serum content of sex hormone and VD3 were detected by enzyme-linked immunosorbent assay (ELISA). The tissues of mammary glands were analyzed by hematoxylin and eosin (HE) stain, and the expression of estrogen receptor α (ERα), progesterone receptor (PR), and VDR were detected by immunohistochemical (IHC) stain. Similarly, the total protein expression of ERα, PR, and VDR were measured by western blot.
Results
Compared with the hyperplasia group, rats in the VD3 groups displayed a marked decrease of the thickness of the mammary glands and the height and diameter of the nipples. The serum estrogen (E2), testosterone (T), luteinizing hormone (LH), and VD3 was markedly decreased in all VD3 groups (P<0.05). The IHC results showed that ERα and PR was decreased in all three VD3 groups; however, VDR was increased. Western blot demonstrated that both ERα and PR were reduced in VD3 groups, while the VDR level was significantly enhanced. Overall, the findings suggested that VD3 could be used in HMG treatment. Conclusions: Supplementation of VD3 could markedly decrease the mammary gland thickness, nipple diameter, and nipple height of rats, accompanied by the decrease of serum E2, T, and LH. Intervention with VD3 can lead to decreased expression of ERa and PR, in conjunction with the increase of VDR.