This study evaluated the effects of comorbid disorders of diabetes and hyperthyroidism in the adult male mice. In total, 32 ICR strain mice were equally distributed into four groups： control （C）, diabetic （D）, diabetic-plus- hyperthyroid （DH）, and hyperthyroid （H）. Mice allocated for diabetes received a single intraperitoneal injection of streptozotocin （STZ） at 200 mg/kg body weight. At the onset of diabetes, one group of mice was concomitantly injected levothyroxine （LT4; 0.3 mg/kg body weight） and the other set of animals received the same treatment independently on a daily basis. The body weight, as well as the testicular and epididymal weights, was reduced markedly in D and DH mice. Higher trends of blood glucose levels were seen in the DH group, in comparison to euthyroid diabetic mice. Thyroid hormones could exert a transient effect on blood glucose homeostasis by altering the serum blood glucose level in diabetic patients. Histomorphometric analysis showed increased luminal sizes of seminiferous tubules, along with decreased epithelial height and atrophic changes in germinal stem cells in the testis of DH and H mice. Caput epididymis of DH mice showed extensive compaction of principal cells, loss of stereocilia, lipid vacuolization, and inflammatory infiltrations; however, damaged tubular integrity, packed clear cells, exfoliated cells, and round sperma- tids were profoundly noticed in the cauda epididymis. Hyperthyroidism elevated the serum testosterone levels in H and DH mice and produced critical damages to the histoarchitecture of the epididymis. Collectively, this experiment en- deavored to mimic the polyglandular autoimmune syndrome, which will be helpful to better understand the reasons for male infertility in diabetic-cum-hyperthyroid patients.
Nazar Ali KOREJOQuan-wei WEIAtta Hussain SHAHFang-xiong SHI
The objective was to investigate the expression of bone morphogenetic protein （BMP） family members in the mouse uterus during the estrous cycle by real-time polymerase chain reaction （PCR） and immunohistochemistry. Uterine samples from Swiss ICR mice were collected and dissected free of surrounding tissue. One uterine horn was snap frozen in liquid nitrogen immediately after collection and stored at -80 ℃for RNA extraction, and the other was fixed in 40 mg/ml paraformaldehyde at room temperature for immunolocalization of BMP2 protein. Real-time PCR analysis showed that the expression level of Bmp2 was significantly higher at proestrus than at estrus and metestrus （P〈0.05）. The relative abundance of Bmp4 exhibited significant fluctuations, but there were no statistically significant differences between the expression levels of Bmp2 and Bmp4 （P〉0.05）. The expression levels of Bmprla and Bmpr2 remained unchanged during estrous cycles. However, the level of Bmprlb mRNA decreased significantly at estrus （P〈0.05）, increasing subsequently at metestrus. Furthermore, the level of Bmprlb mRNA was significantly lower than those of Bmprla and Bmpr2 mRNA at the corresponding stages （P〈0.05）. All three receptor-regulated Smads （R-Smads） detected were differentially expressed in the mouse uterus and the expression levels of Smadl and Smad5 were significantly higher than that of Smad8 （P〈0.05）. In addition, the expression level of Smad4 did not change substantially throughout the estrous cycle. Immunohistochemical experiments revealed that BMP2 protein was differentially expressed and localized mainly in the uterine luminal and glandular epithelial cells throughout the estrous cycle. In conclusion, our results provide information about the variation in the mRNA levels of Bmp2 and Bmp4 and related components of the BMP signaling pathway. The data provide quantitative and useful information about the roles of endometrial BMP proposed and demonstrated by others, such as the degradation an
Yan LIQuan-wei WEIJian-gang FENGMu-lin XURui-hua HUANGFang-xiong SHI
The effects of equine chorionic gonadotropin （eCG） on follicular development and ovulation in cyclic guinea pigs were investigated by histological and immunohistochemical analyses. Three groups of guinea pigs （n=12） were administrated subcutaneously with saline, 20 or 50 IU of eCG, respectively, on cyclic Day 12 （Day 1=vaginal openings）. Ovaries were collected at 4 and 8 d after administration （6 animals per group each time）. The eCG administration induced significant and distinct morphological changes in the ovaries, as it promoted the luteinization of granulosa cells, but not follicular development. In addition, proliferating cell nuclear antigen （PCNA） and steroidogenic acute regulatory protein （STAR） were immunolocalized specifically in luteinized follicles. Our experiments together indicate that eCG administration can induce follicular luteinization but not superovulation in guinea pigs. The eCG in cyclic guinea pigs functions similar to that of luteinizing hormone （LH）, but not follicle-stimulating hormone （FSH）.
