Influence of ROS on Ovarian Functions

High level of ROS (Reactive Oxygen Species), due to an increased production of oxidant species and/or a decreased efficacy of antioxidant system, can lead to oxidative stress (OS) an emerging health risk factor involved in the aging and in many diseases, either in humans or in animals. ROS are a double-edged sword – they serve as key signal molecules in physiological processes, but also have a role in pathological processes involving the female reproductive tract

Redoxomics and Oxidative Stress: From the Basic Research to the Clinical Practice

Potentially oxidant chemical species, which include not only free radicals but also other oxidizing chemical species such as reactive oxygen species (ROS), for example, hydroxyl radical and hydrogen peroxide, and nitrogen reactive species (RNS), for example, nitric oxide, play a relevant role in all biological processes and especially in cell defenses and molecular signaling. Their action is finely modulated by the antioxidant network that is composed either by endogenous or exogenous compounds (e.g., enzymes, peptides, lipids, and vitamins). An impaired modulation of oxidant species can lead to the so-called oxidative stress that is now considered an emerging health risk factor in almost all living organisms including plants, animals, and humans. Indeed, oxidative stress is related to a reduced lifespan and many diseases (e.g., cardiovascular diseases, neurodegenerative disorders, and metabolic diseases) both in humans and in animals. Unfortunately, oxidative stress does not show any clinical picture, but it can be detected only by means of specific laboratory tests. The recent recognition of a specific “redox code” and the definition of a redoxomics as a new “omics” are now enlarging the horizon of the traditional oxidative stress field leading to the definition of the so-called electrophilic stress. The aim of this chapter is to review the basic principles of redox reaction starting from the concept of free radicals and antioxidant in order to define the “electrophilic stress” as an emerging health risk factor for early aging and almost 1000 illness from infectious diseases to cancer. A paragraph is dedicated to the tests to measure oxidative stress in clinical practice either in humans or in animals in order to prevent, to treat and to monitor electrophilic-related diseases

Reactive Oxygen Species (ROS) and Male Fertility

Oxidative energy production is inevitably associated with the generation of reactive oxygen species (ROS), excessive concentrations of which can lead to cellular pathology. A free radical may be defined as any molecule that has one or more unpaired electrons. The superoxide anion, the hydroxyl radical, and the hypochlorite radical are some of the highest reactive radicals of oxygen. Owing to their high reactivity and to their capability of initiating an uncontrolled cascade of chain reactions, ROS produce extensive protein damage and cytoskeletal modifications and inhibit cellular mechanisms. Aerobic organisms are equipped with a powerful battery of mechanisms that protect them from the adverse effects of lipid peroxidation (LPO) and other manifestations of oxygen toxicity. Defective sperm function frequently causes male infertility, due to abnormal flagella movement, failure to recognize the zona, and inhibition of sperm-oocyte fusion. ROS are fundamental mediators of physiological sperm function, such as signal transduction mechanisms that have an effect on fertility. ROS can have positive effects on sperm and the concentration functions depending on the nature and the concentration of the ROS involved. They are necessary in regulating the hyperactivation and the ability of the spermatozoa to undergo acrosome reaction. An increased amount of superoxide anion (O2-) is one of the first steps required by the spermatozoa for induction and development of hyperactivation and capacitation. Numerous studies have shown that oxidative stress plays an important role in the pathophysiology of infertility and assisted fertility. The paternal genome is of primary importance in the normal embryo and fetal development. ROS-induced sperm damage during sperm translation, such as signal transduction through the seminiferous tubules and epididymis, is one of the most important mechanisms leading to sperm DNA damage. Male germ cells are extremely vulnerable to oxidative stress as the sperm membrane is rich in unsaturated fatty acids and lacks the capacity for DNA repair. Spermatozoa are particularly susceptible to ROS-induced damage because their plasma membranes contain large quantities of polyunsaturated fatty acids (PUFA) and their cytoplasm contains low concentrations of the scavenging enzymes. Many clinical and research institutes are investigating the usefulness of antioxidant supplementation and their role in prevention of the infertility problems. Incubation under oxygen in vitro was detrimental to human spermatozoa, decreasing motility and viability. Since then, many reports have associated ROS with impaired sperm function, including decreased motility, abnormal morphology, and decreased sperm-egg penetration. Increasing knowledge of the mechanisms whereby ROS and endogenous antioxidant systems influence reproductive processes can assist to optimize the application of exogenous antioxidants to fertility treatment

Assisted Reproductive Technologies in Safeguard of Feline Endangered Species

The growth of the human population and the escalating consumption of natural resources have reduced wild habitats, modifying the existing balance of biological cycles. Therefore, ex situ conservation efforts have received renewed attention as a potential safeguard for species with an uncertain future in the wild. Most wild felid species are classified as rare, vulnerable, or endangered due to poaching and habitat loss. Any directed action taken by humans to enhance animal reproduction results in assisted reproductive technologies (ART) development. These technologies have been included in programs for the conservation of endangered species. Therefore, ART provide a new approach in the safeguard programs of felid biodiversity. Currently, ART mainly include Artificial Insemination (AI); In Vitro Embryo Production (IVEP) consisting of In Vitro Maturation (IVM), In Vitro Fertilization (IVF), In Vitro Culture (IVC), Embryo Transfer (ET), and Intra Cytoplasmic Sperm Injection (ICSI); gamete/embryo cryopreservation; gamete/embryo sexing; gamete/embryo micromanipulation; Somatic Cell Nuclear Transfer (SCNT); and genome resource banking

Human-Animal Relationship Dysfunction: A Case Study of Animal Hoarding in Italy

"Animal hoarding" or "compulsive hoarding of animals" is a psychiatric disease, which has important social implications and a profound influence on animal welfare. To date, this phenomenon has been little investigated and largely unexplored. The present study aims to systematically describe a case of animal hoarding, which remains unresolved. The report refers to a case of a woman suffering from animal hoarding that emerged in 2005. From March 2014 to December 2019, 450 animals were seized over nine different occasions. This disease had significant implications on the welfare of the animals collected, which lived in poor housing and hygiene conditions that frequently led to their death. Since animal hoarding cases involve sanitary, legal, and veterinary aspects, we believe that a multidisciplinary approach is necessary in order to prevent a recurrence and a new accumulation of animals. A holistic approach should be taken according to the One Health principle that involves different stakeholders at every level in order to adopt an efficient solution

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

Expression of orexin B and its receptor 2 in rat testis

The peptides orexin A (OxA) and orexin B (OxB) deriving from a common precursor molecule, prepro-orexin, by proteolytic cleavage, bind the two G-coupled OX1 and OX2 receptors. While OX1 selectively binds OxA, OX2 shows similar affinity for both orexins. Firstly discovered in the hypothalamus, orexins and their receptors have been found in other brain regions as well as in peripheral tissues of mammals, thus resulting involved in the regulation of a broad variety of physiological functions. While the functional localization of OxA and OX1 in the mammalian genital tract has been already described, the expression of OxB and OX2 and their potential role in the reproductive functions remain to be explored. Here, we investigated the presence of OxB and OX2 in the rat testis by immunohistochemical and biochemical analyses. The results definitely demonstrated the localization of OxB and OX2 in pachytene and second spermatocytes as well as in spermatids at all stages of the cycle of the seminiferous epithelium. The expression of both OX2 mRNA and protein in the rat testis was also established by RT-PCR and Western blotting, respectively. The analysis of the molecular mechanism of action of OxB in the rat testis showed that OxB, in contrast with OxA, is unable to promote steroidogenesis. These results translate into the regulation of diverse biological actions by OxA and OxB in the male gonad

Localization of orexin B and orexin-2 receptor in the rat epididymis

The peptides orexin A (OXA) and orexin B (OXB) derived from the proteolytic cleavage of a common precursor molecule, prepro-orexin, were originally described in the rat hypothalamus. Successively, they have been found in many other brain regions as well as in peripheral organs of mammals and other less evolved animals. The widespread localization of orexins accounts for the multiple activities that they exert in the body, including the regulation of energy homeostasis, feeding, metabolism, sleep and arousal, stress, addiction, and cardiovascular and endocrine functions. Both OXA and OXB peptides bind to two G-coupled receptors, orexin-1 (OX1R) and orexin-2 (OX2R) receptor, though with different binding affinity. Altered expression/activity of orexins and their receptors has been associated with a large number of human diseases. Though at present evidence highlighted a role for orexins and cognate receptors in mammalian reproduction, their central and/or local effects on gonadal functions remain poorly known. Here, we investigated the localization of OXB and OX2R in the rat epididymis. Immunohistochemical staining of sections from caput, corpus and cauda segments of the organ showed intense signals for both OXB and OX2R in the principal cells of the lining epithelium, while no staining was detected in the other cell types. Negative results were obtained from immunohistochemical analysis of hypothalamic and testicular tissues from OX2R knock-out mice (OX2R−/−) and OX1R/OX2R double knock-out (OX1R−/−; OX2R−/−) mice, thus demonstrating the specificity of the rabbit polyclonal anti-OX2R antibody used in our study. On contrary, the same antibody clearly showed the presence of OX2R in sections from hypothalamus and testis of normal mice and rats which are well known to express the receptor. Thus, our results provide the first definite evidence for the immunohistochemical localization of OXB and OX2R in the principal cells of rat epididymis

Expression and potential role of the peptide orexin-A in prostate cancer

The peptides orexin-A and orexin-B and their G protein-coupled OX1 and OX2 receptors are involved in multiple physiological processes in the central nervous system and peripheral organs. Altered expression or signaling dysregulation of orexins and their receptors have been associated with a wide range of human diseases including narcolepsy, obesity, drug addiction, and cancer. Although orexin-A, its precursor molecule prepro-orexin and OX1 receptor have been detected in the human normal and hyperplastic prostate tissues, their expression and function in the prostate cancer (PCa) remains to be addressed. Here, we demonstrate for the first time the immunohistochemical localization of orexin-A in human PCa specimens, and the expression of prepro-orexin and OX1 receptor at both protein and mRNA levels in these tissues. Orexin-A administration to the human androgen-dependent prostate carcinoma cells LNCaP up-regulates OX1 receptor expression resulting in a decrease of cell survival. Noteworthy, nanomolar concentrations of the peptide counteract the testosterone-induced nuclear translocation of the androgen receptor in the cells: the orexin-A action is prevented by the addition of the OX1 receptor antagonist SB-408124 to the test system. These findings indicate that orexin-A/OX1 receptor interaction interferes with the activity of the androgen receptor which regulates PCa onset and progression, thus suggesting that orexin-A and its receptor might represent novel therapeutic targets to challenge this aggressive cancer