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Orexins are neuropeptides with pleiotropic functions, involved in the coordination of multiple versatile physiological processes, in particular related to food intake and several aspects of the reproductive process. Their actions are carried out through the bond with the related Orexin 1 (OXR1) and Orexin 2 (OXR2) G-protein-coupled receptors. Studies on the expression of the orexinergic system in the female genital organs are scarce and limited to preovulatory gametogenic follicles and corpora lutea isolated from the rest of the ovary. As the description of only these structures is insufficient to provide a complete picture of the organ, the present study is aimed to give a panoramic view of all the ovarian structures and cells expressing Orexin A (OXA) and its receptors in their original localization. Double labeling immunofluorescent methods, applied on frozen sections of the whole organ in both follicular and luteal phase, were used to highlight the particular distribution and colocalization of the proteins. For a better recognition of cellular morphology and a better distinction between gametogenic (healthy) and atretic follicles, also a single labeling immunolocalization of OXA on formalin fixed paraffin embedded tissues and a TUNEL staining were performed. The results indicate that OXA and its two receptors subtypes are expressed in all the different structures composing the swine ovary, albeit in different ways, in both phases of the ovarian cycle. In general, OXA and OXR2 appear diffusely distributed within “health”, proliferating and steroid producing cells, while has granular appearance, being presumably associated to cytoplasmic vesicles, in degenerating cells, independently if apoptotic or not. The immunoreactivity for OXR1, instead, is often associated with the nuclear envelope but it is also detectable, to a lesser extent, diffusely distributed in the cytoplasm of growing or steroid producing cells. When cells undertake the path leading to degeneration, also OXR1 immunoreactivity assumes a granular appearance in the cytoplasm and is colocalized with OXA and OXR2. Different roles for the two receptors in the same cell and a different regulation of their expression remain to be investigated. Their comprehension could help studies of follicle development in pig, as part of in vitro oocyte maturation and fertilization programs in livestock. [ABSTRACT FROM AUTHOR]

Recent studies have demonstrated the surprising ability of reproductive endocrine cells to express receptors of innate immunity useful to sense danger in order to avoid disruption of tissue homeostasis. Present research demonstrates the presence of pattern recognition receptors, i.e. toll like receptors (TLR) TLR2, TLR4 and TLR 5 and NOD like receptors (NLR) NOD1 and NOD2 in swine granulosa cells from ovarian follicles> 5 mm. Therefore, our second goal was to expose granulosa cells to different concentrations (1000, 100 and 10 ng/ml) of lipopolysaccharide (LPS) and N -Palmitoyl-S-[2,3-bis(palmitoyloxy)-(2RS)- propyl]-[R]-cysteinyl-[S]-seryl-[S]-lysyl-[S]-lysyl-[S]-lysyl-[S]- lysine (Pam3CSK4), two substances associated with pathogen molecular patterns. Their potential effects on the main functional parameters were monitored: proliferation (through the incorporation of Bromo-deoxy-Uridine), cell viability (by testing the metabolization of MTT salt), steroidogenic activity (by immunoenzymatic examination) and redox status (evaluating the production of superoxide anion by means of the WST test, production of nitric oxide through the use of the Griess test, and the non-enzymatic reducing power, by FRAP test). The data collected show a significant inhibition (p < 0.01) of cell proliferation after treatment with both LPS and Pam3CSK4, while cell viability has not been modified. As for steroidogenesis, treatment with both LPS and Pam3CSK4 significantly inhibited (p < 0.05) the production of 17β-estradiol and progesterone. LPS and Pam3CSK4 stimulated (p < 0.05) the production of superoxide anion and nitric oxide, while inhibited (p < 0.05) the antioxidant power. In conclusion, the study shows that the functionality of granulosa cells is compromised by the exposure to molecular profiles associated with pathogens; the knowledge gathered could lay the theoretical basis for the definition of therapeutic treatments related to diseases that can affect normal reproductive processes. • Innate immunity responds to variations to restore stability. • Toll like (TLRs) and NOD like (NOD) receptors are involved in innate immunity. • We verified the expression of TLRs and NOD in swine granulosa cells (GC). • Pathogen associated molecular patterns (PAMPs) affect GC functions. • Swine GC could perform an innate immunity response. [ABSTRACT FROM AUTHOR]