Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P56851 (epididymal)
 11,273 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sperm undergo maturation acquiring progressive motility and the ability to fertilize oocytes through exposure to the components of the epididymal fluid (EF). Although the establishment of a calcium (Ca(2+)) gradient along the epididymis has been described, its direct effects on epididymal function remain poorly explored. Regucalcin (RGN) is a Ca(2+)-binding protein, regulating the activity of Ca(2+)-channels and Ca(2+)-ATPase, for which a role in male reproductive function has been suggested. This study aimed at comparing the morphology, assessed by histological analysis, and function of epididymis, by analysis of sperm parameters, antioxidant potential and Ca(2+) fluxes, between transgenic rats overexpressing RGN (Tg-RGN) and their wild-type littermates. Tg-RGN animals displayed an altered morphology of epididymis and lower sperm counts and motility. Tissue incubation with (45)Ca(2+) showed also that epididymis of Tg-RGN displayed a diminished rate of Ca(2+)-influx, indicating unbalanced Ca(2+) concentrations in the epididymal lumen. Sperm viability and the frequency of normal sperm, determined by the one-step eosin-nigrosin staining technique and the Diff-Quik staining method, respectively, were higher in Tg-RGN. Moreover, sperm of Tg-RGN rats showed a diminished incidence of tail defects. Western blot analysis demonstrated the presence of RGN in EF as well as its higher expression in the corpus region. The results presented herein demonstrated the importance of maintaining Ca(2+)-levels in the epididymal lumen and suggest a role for RGN in sperm maturation. Overall, a new insight into the molecular mechanisms driving epididymal sperm maturation was obtained, which could be relevant to development of better approaches in male infertility treatment and contraception.
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PMID:Sperm parameters and epididymis function in transgenic rats overexpressing the Ca2+-binding protein regucalcin: a hidden role for Ca2+ in sperm maturation? 2361 21

Potato chips (PC) contain abundant amounts of the free radical scavenger ascorbic acid (AA) due to the rapid dehydration of potato tubers (Solanum tuberosum) that occurs during frying. To evaluate the antioxidant activity of PC, this study examined reactive oxygen species (ROS) levels in tissues from SMP30/GNL knockout (KO) mice that cannot synthesize AA and determined AA and ROS levels after the animals were fed 20 and 10% PC diets for 7 weeks. Compared with AA-sufficient mice, AA-depleted SMP30/GNL KO mice showed high ROS levels in tissues. SMP30/GNL KO mice fed a PC diet showed high AA and low ROS levels in the brain, heart, lung, testis, soleus muscle, plantaris muscle, stomach, small intestine, large intestine, eyeball, and epididymal fat compared with AA-depleted mice. The data suggest that PC intake increases AA levels and enhances ROS scavenging activity in tissues of SMP30/GNL KO mice, which are a promising model for evaluating the antioxidant activity of foods.
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PMID:Potato chip intake increases ascorbic acid levels and decreases reactive oxygen species in SMP30/GNL knockout mouse tissues. 2518 Jul 84

Age-related changes, namely the increase in oxidative stress (OS) with the consequent sperm damage, result in decreased male fertility. Regucalcin (RGN) is a Ca2+-binding protein that has been shown to have beneficial effects on spermatogenesis by suppressing OS and chemical/radiation-induced damage. This work aims to evaluate whether RGN overexpression reduces the ageing-associated decline of male reproductive function. Sperm and testicular function analysis were performed in young-adult and senescent transgenic rats overexpressing RGN (Tg-RGN) comparatively with their wild-type (Wt) littermates. The gonadosomatic index (GI), tubular differentiation index and the expression levels of RGN and other proliferation regulators were evaluated. Moreover, the sperm parameters, OS analysis and immunolocalization of RGN were assessed, as well as morphometric evaluation of epididymal tubules. Both GI and sperm counts were reduced in the senescent Wt rats, but maintained in the Tg-RGN. Also, the levels of stem cell factor (SCF), c-Kit, and Akt were maintained in the testis of aged Tg-RGN rats, suggesting that the normal spermatogenic output was preserved over time in these animals, an effect not observed in Wt. Senescent Tg-RGN rats also presented lower sperm lipid peroxidation and total oxidant status relative to the Wt. Furthermore, aged Tg-RGN rats displayed higher sperm viability, higher frequency of sperm with normal morphology, and reduced incidence of head and neck/midpiece defects when compared with Wt, which may be a consequence of the lower OS levels found in the sperm of these animals. Interestingly, RGN expression increased with ageing in sperm, being mainly localized in the acrosome. Altogether, these findings indicate that the modulation of RGN levels may alleviate the age-related decline in sperm quality and testicular function.
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PMID:Overexpression of regucalcin mitigates the ageing-related changes in oxidative stress and sperm quality. 3289 22