La salvaguardia delle specie ittiche di allevamento attraverso la conoscenza del loro benessere

Il benessere animale in acquacoltura è divenuto una tematica di grande interesse a livello nazionale, europeo e mondiale. La crescente richiesta di prodotto ittico, in considerazione sia dell’aumento della popolazione mondiale, sia del sempre maggiore apprezzamento per le qualità del prodotto e per le sue proprietà nutrizionali, ha posto nuovi interrogativi in termini di sicurezza e di benessere. Le ricerche condotte sul campo stimolate anche dai rispettivi governi a tutela del prodotto, hanno permesso di accrescere le conoscenze sull’anatomia, la fisiologia e sul comportamento dei pesci. La capacità da parte del pesce di percepire l’ambiente circostante, così come il suo comportamento in relazione ai conspecifici, ha permesso di chiarire molti aspetti legati alle sue attività e, al contempo, di riconoscere per queste specie il concetto di essere senziente. Sicuramente le conoscenze fino ad oggi acquisite in relazione a più moderne tecnologie di biologia e di genetica molecolare hanno contribuito ad approfondire le suddette tematiche con interessanti risultati

Urocortins in the mammalian endocrine system

Urocortins (Ucns), peptides belonging to the corticotropin-releasing hormone (CRH) family, are classified into Ucn1, Ucn2, and Ucn3. They are involved in regulating several body functions by binding to two G protein-coupled recep- tors: receptor type 1 (CRHR1) and type 2 (CRHR2). In this review, we provide a historical overview of research on Ucns and their receptors in the mammalian endocrine system. Although the literature on the topic is limited, we focused our attention particularly on the main role of Ucns and their receptors in regulating the hypothalamic–pituitary–adre- nal and thyroid axes, reproductive organs, pancreas, gastrointestinal tract, and other tissues characterized by “diffuse” endocrine cells in mammals. The prominent function of these peptides in health conditions led us to also hypothesize an action of Ucn agonists/antagonists in stress and in various diseases with its critical consequences on behavior and physiology. The potential role of the urocortinergic system is an intriguing topic that deserves further in-depth investi- gations to develop novel strategies for preventing stress-related conditions and treating endocrine diseases

Tumor-educated mesenchymal stem cells promote pro-metastatic phenotype

Multipotent mesenchymal stem cells (MSCs) are recruited into tumor microenvironment in response to multiple signals produced by cancer cells. Molecules involved in their homing to tumors are the same inflammatory mediators produced by injured tissues: chemokines, cytokines and growth factors. When MSCs arrive into the tumor microenvironment these are “educated” to have pro-metastatic behaviour. Firstly, they promote cancer immunosuppression modulating both innate and adaptive immune systems. Moreover, tumor associated-MSCs trans-differentiating into cancer-associated fibroblasts can induce epithelial-mesenchymal-transition program in tumor cells. This process determinates a more aggressive phenotype of cancer cells by increasing their motility and invasiveness and favoring their dissemination to distant sites. In addition, MSCs are involved in the formation and modelling of pre-metastatic niches creating a supportive environment for colonization of circulating tumor cells. The development of novel therapeutic approaches targeting the different functions of MSCs in promoting tumor progression as well as the mechanisms underlying their activities could enhance the efficacy of conventional and immune anti-cancer therapies. Furthermore, many studies report the use of MSCs engineered to express different genes or as vehicle to specifically deliver novel drugs to tumors exploiting their strong tropism. Importantly, this approach can enhance local therapeutic efficacy and reduce the risk of systemic side effects

Glutathione concentration and gamma-glutamyltransferase activity in water buffalo colostrum

Evidence is presented that the buffalo mammary gland contains enzymes that catalyse the synthesis and utilization of glutathione. A significant, inverse correlation (r = 0.79) was detected between colostrum gamma-glutamyltransferase (GGT) and glutathione (GSH), suggesting that the enzyme uses GSH as a substrate for its activity. A similar trend was shown in mammary gland homogenates (r = 0.75). Our results show that GSH is secreted into buffalo colostrum and suggest that the enzyme GGT degrades it. To the authors' knowledge, this is the first demonstration of the involvement of GGT-mediated GSH metabolism in the synthesis of colostrums, which elucidates the role of the enzyme that has always been reported very high in colostrum. © 2009 Blackwell Verlag GmbH

Orexin A-Mediated Modulation of Reproductive Activities in Testis of Normal and Cryptorchid Dogs: Possible Model for Studying Relationships Between Energy Metabolism and Reproductive Control

Orexin A (OxA) is a neuropeptide produced in the lateral hypothalamus that performs pleiotropic functions in different tissues, including involvement in energy homeostasis and reproductive neuroendocrine functions. The role of OxA is particularly important given the well-studied relationships between physiological mechanisms controlling energy balance and reproduction. The enzyme P450 aromatase (ARO) helps convert androgens to estrogens and has roles in steroidogenesis, spermatogenesis, and energy metabolism in several organs. The goal of this study was thus to investigate the role of OxA in ARO activity and the effects of this regulation on reproductive homeostasis in male gonads from healthy and cryptorchid dogs. The cryptorchidism is a specific condition characterized by altered reproductive and metabolic activities, the latter of which emerge from impaired glycolysis. OxA helps to stimulate testosterone (T) synthesis in the dog testis. We aimed to investigate OxA-mediated modulation of 17β-estradiol (17β-E) synthesis, ARO expression and metabolic indicators in testis of normal and cryptorchid dogs. Our results indicate putative effects of OxA on estrogen biosynthesis and ARO activity based on western blotting analysis and immunohistochemistry for ARO detection and in vitro tests. OxA triggered decrease in estrogen production and ARO activity inhibition; reduced ARO activity thus prevented the conversion of T to estrogens and increasing OxA-mediated synthesis of T. Furthermore, we characterized some metabolic and oxidative modulations in normal and cryptorchid dog's testis. The steroidogenic regulation by OxA and its modulation of ARO activity led us to hypothesize that OxA is a potential therapeutic target in pathological conditions associated with steroidogenic alterations and OxA possible involvement in metabolic processes in the male gonad

VALUTAZIONE DEL CALCIO INTRACELLULARE IN PIASTINE DI CANI SANI ED AFFETTI DA LEISHMANIOSI

Le piastrine rappresentano gli elementi cellulari fondamentali per il processo di regolazione dell’emostasi. La loro interazione con l’endotelio vasale riveste un ruolo fondamentale sia nella fisiologia che nella fisiopatologia della coagulazione. fisiologicamente, infatti, le piastrine hanno la capacità di aderire alla parete del vaso solo dopo attivazione da parte dell’endotelio vasale. In condizioni patologiche, come quelle causate dalla rottura di una placca aterosclerotica, le piastrine aderiscono all’endotelio, si attivano e reclutano numerose altre piastrine per la formazione del tappo piastrinico. In medicina veterinaria, diversamente dalla medicina umana, la conoscenza dei meccanismi fisiologici specifici alla base di tali processi è piuttosto scarsa. Le piastrine subiscono fenomeni di attivazione, fra i quali è possibile menzionare, lo shape change, l’attivazione del recettore per il fibrinogeno che causa l’aggregazione delle piastrine, il rilascio del contenuto dei granuli e la produzione di trombossano A2 (Gachet C. et al., 1996, Mills D.C.B., 1996). Tali fenomeni sono mediati da modificazioni del calcio intracellulare che origina dal rilascio di calcio dagli store intracellulari e dall’entrata di calcio dal mezzo extracellulare (Rink T.J. et al., 1985, Rink T.J. et al., 1990). D’altro canto però, sono note numerose patologie nel cane, tra cui forme di Leishmaniosi eo Ehrlichiosi, che comportano seria compromissione della funzione coagulativa (Harrus S. et al., 1996; Weiss D.J. et al., 1995). La leishmaniosi, in particolare, è una zoonosi largamente diffusa nelle zone costiere del Mediterraneo caratterizzata da una alterazione della coagulazione spesso asintomatica che si inserisce in un quadro sintomatologico estremamente vario. In precedenti ricerche abbiamo mostrato che, in corso di leishmaniosi, si verifica un danno piastrinico di entità variabile che, peraltro, non trova completa risoluzione con le terapie normalmente utilizzate in corso di tale patologia. I meccanismi attraverso i quali l’aggregazione piastrinica risulta alterata in corso di leishmaniosi non sono ancora chiari. Per tale motivo, l’obiettivo di questo studio è stato quello di valutare le variazioni di calcio nelle piastrine di cani sani ed affetti da leishmaniosi allo scopo di raggiungere una migliore comprensione dei meccanismi responsabili di alterazioni dell’emostasi in corso di tale patologia

Expression levels of the focal adhesion-associated proteins paxillin and p130CAS in canine and feline mammary tumors

International audiencePaxillin and p130$^{{\rm CAS}}$ are two adaptor proteins localized at the focal adhesions which play an important role in cell signaling, cell motility and oncogenic transformation. In this study we evaluated the levels of paxillin and p130$^{{\rm CAS}}$ in feline and canine mammary tumor tissues at different stages of malignancy. The results obtained by Western blotting analysis showed no significant differences in the amounts of paxillin and p130$^{{\rm CAS}}$ between normal and non-invasive tumor tissues. By contrast, mammary tumor tissues with the invasive phenotype showed lower levels of paxillin $P < 0.01$ and higher levels of p130$^{{\rm CAS}}$ $P < 0.001$ than normal tissues. The decrease $P < 0.001$ of the amount of paxillin and the increase $P < 0.001$ of p130$^{{\rm CAS}}$ levels were correlated with the progression stage of malignancy. Since paxillin and p130$^{{\rm CAS}}$ are involved in regulating cell migration, our results suggest that low levels of paxillin together with high levels of p130$^{{\rm CAS}}$ expression may cause certain breast cancers to be more motile and possibly more aggressive. Thus, both paxillin and p130$^{{\rm CAS}}$ may represent useful prognosticators of feline and canine breast cancer malignancy

Does Orexin B-Binding Receptor 2 for Orexins Regulate Testicular and Epididymal Functions in Normal and Cryptorchid Dogs?

Orexins A (OXA) and B (OXB) and the receptors 1 (OX1R) and 2 (OX2R) for orexins are hypothalamic peptides found in several mammalian organs and participated to the control of a wide assortment of physiological and pathological functions. The distribution of OXA and OX1R has been extensively studied in the male gonad of mammals. Here, we examined the expression and localization of OXB and OX2R as well as their possible involvement in the regulation of testicular and epididymal functions, in healthy and cryptorchid dogs, employing some techniques such as immunohistochemistry, Western blotting, and real-time RT-PCR. In vitro tests were also carried out for evaluating the steroidogenic effect of OXB. OXB and OX2R were expressed in spermatocytes, spermatids, and Leydig cells in normal testis. Their localization was restricted to Sertoli and Leydig cells in cryptorchid conditions. OXB was found to be localized in all tracts of both normal and cryptorchid epididymis, whereas OX2R was found only in the caput. Because the small molecular weight of the peptides OXA and OXB, the expression of their precursor prepro-orexin (PPO), OX1R, and OX2R proteins and mRNAs were investigated by means of Western blot and real-time RT-PCR analyses, respectively, in all tested groups of. In particular, the mRNA level expression of all three genes was higher in cryptorchid dogs than in normal ones. In vitro tests demonstrated that OXB—by binding OX2R—is not involved in testicular steroidogenic processes. Therefore, the findings of this study might be the basis for further functional and molecular studies addressing the possible biochemical effects of OXB and OX2R in normal and pathological conditions of the male reproductive system