Aquaporins Are Differentially Regulated in Canine Cryptorchid Efferent Ductules and Epididymis

The efferent ductules and the epididymis are parts of the male reproductive system where spermatozoa mature. Specialized epithelial cells in these ducts contribute to the transport of fluids produced by spermatozoa's metabolic activity. Aquaporins (AQPs) have been demonstrated to be expressed in the spermatozoan membrane and testis epithelial cells, where they contribute to regulating spermatozoan volume and transit through environments of differing osmolality. Due to the lack of detailed literature regarding AQP expression in the canine male genital tract, the aim of this study was to investigate both the distribution and expression of AQP7, AQP8, and AQP9 in the efferent ductules and epididymal regions (caput, corpus, and cauda) from normal and cryptorchid dogs by using immunohistochemistry, Western blotting, and real-time reverse transcription polymerase chain reaction (RT-PCR). Our results show different patterns for the distribution and expression of the examined AQPs, with particular evidence of their upregulation in the caput and downregulation in the cauda region of the canine cryptorchid epididymis. These findings are associated with a modulation of Hsp70 and caspase-3 expression, suggesting the participation of AQPs in the luminal microenvironment modifications that are peculiar characteristics of this pathophysiological condition

Cellular distribution of aquaporins in testes of normal and cryptorchid dogs: A preliminary study on dynamic roles

Fluid regulation within the male gonad is an important process for promoting sperm differentiation and maturation. Aquaporins (AQPs) are a family of thirteen integral membrane proteins involved in these processes. The expression of several genes of AQPs occurs in the male reproductive tract of humans and other animal species, although there are few studies on domestic animals. In this study, the localization of AQP7, AQP8, and AQP9 as well as the abundances of protein and mRNA transcripts were examined in normal and cryptorchid dog testes. There was immunohistochemical localization of AQP7, AQP8, and AQP9 in both the tubular and interstitial compartments of the normal and retained testes and crytorchid dogs, albeit there was an obvious difference in cellular localization with the testes from the cryptorchid dogs. These results were supported by western blotting and real-time RT-PCR analyses, there was a lesser AQP7 and greater AQP9 abundance of protein and mRNA transcripts in the cryptorchid testis. These findings indicate combined testicular functions of AQPs in cell volume regulation. In addition, with the cryptorchid condition characterized there was a different cellular distribution of AQPs supporting the thought that early detection is important for controlling possible side effects of cyptorchidism, such as pre-neoplastic and carcinogenic outcomes. © 2019 Elsevier B.V

Differential abundances of AQP3 and AQP5 in reproductive tissues from dogs with and without cryptorchidism

quaporins (AQPs) are integral transmembrane proteins facilitating transport of water and small solutes, such as glycerol and urea, between cells. In male reproductive tracts, AQPs maintain a milieu conducive for sperm formation, maturation, and storage. The aim of this study was to clarify effects of testicular and epidydimal function on male fertility by investigating localisation and abundances of AQP3 and AQP5 in testes and epididymal segments from dogs with and without unilateral cryptorchidism. Immunohistochemistry results indicated AQP3 and AQP5 have different distribution patterns in reproductive tissues of dogs with and without unilateral cryptorchidism. The AQP3, an aquaglyceroprotein, is present in different germ and Sertoli cells in testis of dogs without cryptorchidism. The AQP5 protein was not detected in germ cells but was present in Sertoli and Leydig cells and in endothelia of blood vessels. In cryptorchid dogs, AQP3 was detected in early-developing germ and Sertoli cells, and AQP5 had a distribution pattern similar to testes of dogs without cryptorchidism. In the epididymis, AQP3 and AQP5 were localised in epithelial cells of dogs with and without cryptorchidism in a cell-specific manner. The AQP3 and AQP5 protein was in larger abundance in the gonads from dogs with and without cryptorchidism. In contrast, AQP3 and AQP5 abundance increased in each segment of the cryptorchid epididymis, likely as a compensatory mechanism associated with the pathologic condition. These results indicate involvement of AQP3 and AQP5 in spermatogenesis and sperm maturation. Results from the present study indicate dogs are a useful for comparative reproductive biology studie

Effects of orexins on 17β-estradiol synthesis and P450 aromatase modulation in the testis of alpaca (Vicugna pacos).

The steroidogenic enzyme P450 aromatase (ARO) has a key role in the conversion of testosterone (T) into estrogens (E), expressed as 17β-estradiol. The presence and localization of this key enzyme have not been described before in the South American camelid alpaca (Vicugna pacos). In our previous studies of the expression and biological effects of orexin A (OxA) and OxB on the alpaca testis demonstrated that OxA, via its specific receptor 1 (OX1R), stimulated T synthesis. In order to extend these findings, we presently explored the presence and localization of ARO in the alpaca male gonad, and the possible correlation between ARO and the orexinergic complex. Western blotting and immunohistochemistry demonstrated the presence of ARO in tissue homogenates and its localization in the tubular and interstitial compartments of the alpaca testis, respectively. The addition of OxA to fresh testicular slices decreased the 17β-estradiol E levels. This effect was annulled by the sequential addition of the selective OX1R antagonist, SB-408124. OxB incubation did not have any effect on the biosynthesis of E. Furthermore, the OxA-mediated down-regulation of E secretion could be ascribed to ARO inhibition by exogenous OxA, as indicated by measurement of ARO activity in tissue slices incubated with OxA. Overall, our findings suggest that locally secreted OxA interacting with OX1R could indirectly inhibit ARO activity, disabling the conversion of T to E, and consequently lowering E biosynthesis and increasing the production of T in mammalian testis

Effect of colostrum and milk on small intestine expression of AQP4 and AQP5 in newborn buffalo calves.

Functional studies indicate differences in newborn gastrointestinal morphology and physiology after a meal. Both water and solutes transfer across the intestinal epithelial membrane appear to occur via aquaporins (AQPs). Given that the physiological roles of AQP4 and AQP5 in the developing intestine have not been fully established, the objective of this investigation was to determine their distribution, expression and respective mRNA in the small intestine of colostrums-suckling buffalo calves by using immunohistochemistry, Western blot, and reverse transcriptase-PCR analysis. Results showed different tissue distribution between AQP4 and AQP5 with the presence of the former along the enteric neurons and the latter in the endocrine cells. Moreover, their expression levels were high in the ileum of colostrum-suckling buffalo calves. The data present a link between feeding, intestinal development and water homeostasis, suggesting the involvement of these channel proteins in intestinal permeability and fluid secretion/absorption during this stage of development after birth

Synthesis, molecular modeling and biological evaluation of two new chicoric acid analogs

Two conformationally constrained compounds similar to chicoric acid but lacking the catechol and carboxyl groups were prepared. In these analogues, the single bond between the two caffeoyl fragments has been replaced with a chiral oxirane ring and both aromatic residues modified protecting completely or partially the catechol moiety as methyl ether. Preliminary molecular modelling studies carried out on the two analogues showed interactions near the active site of HIV integrase; however, in comparison with raltegravir, the biological evaluation confirmed that CAA-1 and CAA-2 were unable to inhibit infection at lower concentration

ANALISI DELL’INDICE DI INTERAZIONE BAMBINO-PETS IN FATTORIA ZOOANTROPOLOGICA: STUDIO PILOTA

INTRODUZIONE - La didattica applicata alla zooantropologia prevede un’attuazione in campo educativo e pedagogico dei principi zooantropologici; essa si prefigge un duplice obiettivo: di ridurre il gap relazionale tra animali e giovani generazioni e di recuperare i contenuti e le valenze della relazione, al fine dell’utilizzo pedagogico ed educativo. Nasce un nuovo modello educativo che pone al centro delle strutture pedagogiche l’animale, non più come oggetto da sfruttare, ma come soggetto che aiuti il bambino nella sua crescita educativa (1,2). In quest’ottica generale, la Fattoria Zooantropologica sembra essere un buon sistema in grado di permettere la “fruizione” da parte di bambini e\o soggetti con disabilità di questo modello relazionale e di consentire, altresì, attività e terapie assistite con gli animali (3,4). La Fattoria Zooantropologica offre l’opportunità di attivare la relazione reciproca in un ambiente nuovo, attraente e confortevole tra il fruitore e l’animale che giova di un habitat naturale e familiare. L’esperienza diretta permette ai bambini di usare tutti i loro sensi per imparare: più i bambini vedono, toccano, odorano, sentono, gustano, più imparano (5,6). Partendo da questi presupposti, lo studio si è posto l’obiettivo di effettuare una valutazione del gradimento delle differenti specie animali, attraverso l’analisi degli indici di interazione dei bambini rispetto agli animali presenti in fattoria, al fine di fornire delle linee guida nella scelta del pet in relazione ad una amplificazione delle risposte cognitive ed emozionali del bambino