Distribution of superoxide dismutase 1 and glutathione peroxidase 1 in the cyclic canine endometrium.
Superoxide dismutase (SOD) and glutathione peroxidase (GPx) are two important antioxidant enzymes involved in tissue homeostasis by protecting cells and tissues from an accumulation of reactive oxygen species. Information concerning antioxidant enzymes in the canine uterus is almost inexistent. This work intends to establish the pattern of distribution of SOD1 and GPx1 immunoreaction in canine endometrium throughout the estrous cycle, using 46 endometrium samples of healthy dogs representing different cycle stages (anestrus-10, proestrus-10, estrus-10, early diestrus-7, and diestrus-9). SOD1 distribution in canine endometrium showed cyclic variations (P ≤ 0.001), with higher immunoscores in the progesterone-associated stages. Changing immunoreaction also concerned the different epithelial structures considered (surface epithelium, superficial glandular epithelium, and deep glandular epithelium) (P ≤ 0.001), but it was always higher than in the stroma (P ≤ 0.001). Deep glandular epithelial cells usually showed higher scores of immunoreaction compared with the other epithelial cells. Interestingly, in epithelial cells, distinct subcellular patterns for SOD1 were seen: the nuclear labeling was observed in estrus and early diestrus (P ≤ 0.001), whereas an apical reinforcement was observed in estrus (P = 0.011) in the glandular epithelia but not in the surface epithelia. In general, GPx1 distribution in canine endometrium remained relatively unchanged throughout the estrous cycle (P = 0.169) despite the slight decrease observed from proestrus to early diestrus. The highest scores were found in anestrus and diestrus (P < 0.05), varying with of the structure considered. An apical reinforcement pattern was also found for this molecule, which peaked in proestrus and estrus (P < 0.005). In summary, the present study showed that SOD1 and GPx1 are consistently distributed in the canine endometrium. The cyclic changes registered for both molecules suggest that they may play important roles in endometrial physiology, probably in apoptosis and proliferation.
Centro de Ciência Animal e Veterinária (CECAV), Universidade de Trás-os-Montes e Alto Douro, Vila Real, Portugal.
Celso
C
Santos
Centro de Ciência Animal e Veterinária (CECAV), Universidade de Trás-os-Montes e Alto Douro, Vila Real, Portugal.
Maria Dos Anjos
Mdos A
Pires
Centro de Investigação e Tecnologias Agroambientais e Biológicas (CITAB), Universidade de Trás-os-Montes e Alto Douro, Vila Real, Portugal.
Dario
D
Santos
Centro de Ciência Animal e Veterinária (CECAV), Universidade de Trás-os-Montes e Alto Douro, Vila Real, Portugal. Electronic address: rtpayan@gmail.com.
Rita
R
Payan-Carreira
D000818:Animals; D004285:Dogs / Q000502:physiology*; D004717:Endometrium / Q000201:enzymology*; D030762:Estrous Cycle / Q000502:physiology*; D005260:Female; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D005979:Glutathione Peroxidase / Q000235:genetics / Q000378:metabolism*; D000072105:Superoxide Dismutase-1 / Q000235:genetics / Q000378:metabolism*; D000094765:Glutathione Peroxidase GPX1
D005979:Glutathione Peroxidase; D000072105:Superoxide Dismutase-1; D000094765:Glutathione Peroxidase GPX1
Antioxidant enzymes; Dogs; Immunohistochemistry; Oxidative stress; Reactive oxygen species; Uterus