Osteopontin expression in dromedary camel's conceptuses during the peri-implantation period.

The reproductive efficiency of dromedary camels is hindered by challenges such as early embryonic mortality, which may be attributed to a lack of synchronization between conceptus signalling and uterine receptivity. Understanding the intricate biological processes involved in feto-maternal interactions during implantation is crucial to address these limitations. Osteopontin (OPN) is a protein involved in cell signalling and adhesion, playing a crucial role in embryonic implantation. Previous studies have shown the presence of OPN in the uterine endometrium of various mammalian species including dromedary camels. However, the expression pattern of OPN in dromedary conceptuses remains unexplored. Thus, the current study aimed, for the first time, to investigate the temporospatial expression of OPN in dromedary conceptuses during the peri-implantation period at Days 8, 10, and 12 of pregnancy. Twelve conceptuses were recovered non-surgically from pregnant females on Days 8, 10, 12 of pregnancy. Quantitative real-time PCR (qrt-PCR), immunohistochemistry (IHC), and immunofluorescence (IF) were employed for analysis of the expression of OPN mRNA and protein. The results revealed significant increases in both OPN mRNA and protein expression started on Day 10 and peaked at Day 12 of pregnancy. Immuno-localization confirmed the presence of OPN protein in the trophectoderm and endoderm of dromedary conceptuses. In conclusion, the expression and localization of OPN during the peri-implantation period in dromedary conceptuses imply its involvement as a crucial reproductive factor and its upregulation during this period, with a pronounced increase close to attachment time (Day 12 of pregnancy) further supports its role in embryo adhesion, implantation, and placentation.

MUC1 regulation in the left and right uterine horns and conceptus trophectoderm during the peri-implantation period of dromedary camel.

Pregnancy maintenance in dromedary camels poses significant challenges, including early embryonic loss in the left uterine horn (LH) and unsuccessful pregnancy in the right uterine horn (RH), suggesting a potential asynchrony between conceptus signaling and uterine receptivity. The transition of the uterine epithelium from a pre-receptive to a receptive state requires a delicate balance of adhesion-promoting and anti-adhesion molecules. Mucin-1 (MUC1) acts as an anti-adhesive molecule on the uterine luminal (LE) and glandular (GE) epithelium. Downregulation of MUC1 is believed to be crucial for successful embryo attachment in various mammals. This study aimed to investigate the temporospatial expression of MUC1 in the LH and RH on Days 8, 10, and 12 pregnant dromedaries and their conceptuses. Quantitative real-time polymerase chain reaction (qrt-PCR), Western blot analysis, immunohistochemistry, and immunofluorescence techniques were employed to assess MUC1 expression at the mRNA and protein levels. The results demonstrated a reduction in MUC1 mRNA expression on Day 8, then increased on Day 10, followed by a decrease on Day 12 in LH. While the RH exhibited progressive increases, peaking on Day 12. However, MUC1 expression constantly exhibited higher levels in RH than in LH in all days. Two bands were detected at 150-kDa and 180-kDa, with the highest intensity observed on Day 10. Spatially, MUC1 was localized in the apical, cytoplasmic, and lumen of uterine glands only. MUC1 was barely detectable on Day 8 but gradually increased on Days 10 and 12 in both horns. Likewise, the RH exhibited higher MUC1 signals than the LH on Days 10 and 12. In the conceptuses, MUC1 mRNA increased on Day 8, peaked on Day 10, and declined on Day 12. Notably, MUC1 protein was detected in both the trophectoderm and endoderm, with high expression observed on Day 10 and reduced by Day 12. In conclusion, the decrease in MUC1 expression on Day 8 in the LH may be associated with maternal recognition of pregnancy (MRP), and the increase on Day 10 may related to embryo protection and movement, while the subsequent decrease on Day 12 could be linked to the embryo attachment and preparation for the implantation. Conversely, the increase of MUC1 in the RH implies a role in the anti-adhesion mechanism. These findings contribute to understanding MUC1's involvement in reproductive processes and provide insights into the complex mechanisms underlying successful pregnancy establishment and maintenance in dromedary camels.

Immunolocalization and expression of Siglec5 protein in the male reproductive tract of dromedary camel during rutting season.

Lectins are carbohydrate-binding proteins that are highly selective for sugar groups on other molecules. Siglec5 is a cell-surface lectin that belongs to the sialic acid-binding Ig-like lectins (Siglecs) and acts as a suppressor of immune responses. In this study, immunohistochemistry, western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) were used to detect the expression of Siglec5 in the male reproductive tract of dromedary camels during the rutting season. Siglec5 displayed strong immunostaining in the cranial and caudal testicular regions and moderate immunostaining in the rete testis. Different parts of the epididymis showed varying immunoreactions to Siglec5. The spermatozoa in the testes and epididymis also showed positive immunostaining for Siglec5, whereas, the vas deferens showed negative immunostaining for the protein. The results obtained by western blotting confirmed the immunohistochemical detection of the protein in the testicular and epididymal tissues. The results of qRT-PCR showed that Siglec mRNA was expressed differently in each part of the testis and epididymis; the highest levels of expression were observed in the caudal part of the testis and in the head of the epididymis. In conclusion, the present study revealed that Siglec5 is mainly located in the testis and epididymis, where sperm production and maturation occur. Therefore, this protein may play an essential role in the development, maturation and protection of camel sperm.

Temporospatial expression of osteopontin in both left and right uterine horns during the peri-implantation period of dromedary camel.

Pregnancy in camels is established and maintained predominantly in the left uterine horn (98% frequency), whereas pregnancies occurring in the right horn result in early embryonic death. Aside from other reasons such as asynchrony of conceptus signaling and uterine receptivity, this phenomenon contributes to low reproductive efficiency in camels. The current research focuses on the expression of osteopontin (OPN), an extracellular matrix protein and adhesion molecule involved in implantation in mammals. Based on the differences in the pregnancy rate between the left and right horns, the temporal and spatial OPN expression was analyzed during the peri-implantation period on Days 8, 10, and 12. Results showed that OPN expression on Day 10 significantly increased by 14.5 fold in the left and 8.4-fold in the right uterine horn. By Day 12, OPN expression increased to 39.4 fold in the left and increased 7-fold in the right horn compared with non-mated females. Only the full length, 70-kDa OPN, was detected and upregulated with advancing pregnancy, with higher intensity in the left uterine horns than in the right. Spatially, OPN was predominantly localized on the apical uterine luminal and glandular epithelium in all camels. Moreover, OPN was detected in the stratum compactum stroma of pregnant camels. In conclusion, OPN mRNA and protein were detected and upregulated during the peri-implantation period, with higher OPN expression detected in the left uterine horn than in the right. OPN may be regulated by the presence of the embryo in the left uterine horn due to its role in embryo adhesion, implantation and placentation.

Effect of Momordica charantia on Insulin Immune-Reactive Pancreatic Beta Cells and Blood Glucose Levels in Streptozotocin-Induced Diabetic Rats.

The present study was conducted to determine the antidiabetic effect of Momordica charantia (MC) on pancreatic islets of Langerhans in streptozotocin (STZ)-induced diabetic male Wistar rats in relation to the distribution of insulin immuno-positive beta cells. MC was fed to rats at 2, 5, and 10% of the standard diet for 12 wk. After sacrification, the pancreatic tissues were obtained for histopathological and immunohistochemical observations. In addition, monitoring of fasting blood glucose was applied each month during experimental period. The results revealed that the oral doses of MC at 5% and 10% of the daily diet increased the percentage of insulin-positive pancreatic beta cells as well as the size and number of pancreatic islets. Moreover, significant (p≤0.0001) dose and time-depended reduction in fasting blood glucose levels were observed. In conclusion, these results suggest that MC induces antidiabetic effects via regeneration of insulin-positive pancreatic beta cells and increase the number of insulin secretory granules hence, blood glucose reduction.