Lack of NWC protein (c11orf74 homolog) in murine spermatogenesis results in reduced sperm competitiveness and impaired ability to fertilize egg cells in vitro

<div><p>NWC is an uncharacterised protein containing three strongly conserved domains not found in any other known protein. Previously, we reported that the NWC protein is detected in cells in the germinal layer in murine testes (strain: C57BL/6), and its knockout results in no obvious phenotype. We determined the NWC expression pattern during spermatogenesis, and found this protein in spermatocytes and round spermatids, but not in epididymal sperm. Although NWC knockout males are fertile, we further characterised their reproductive potential employing non-standard mating that better simulates the natural conditions by including sperm competition. Such an approach revealed that the sperm of knockout males fail to successfully compete with control sperm. After analysing selected characteristics of the male reproductive system, we found that <i>NWC</i> knockout sperm had a reduced ability to fertilize cumulus-intact eggs during IVF. This is the first report describing a subtle phenotype of <i>NWC</i> knockout mice that could be detected under non-standard mating conditions. Our results indicate that NWC plays an important role in spermatogenesis and its deficiency results in the production of functionally impaired sperm.</p></div

The role of G-protein-coupled membrane estrogen receptor in mouse Leydig cell function : in vivo and in vitro evaluation

AbstractIn this study, G-coupled estrogen receptor (GPER) was inactivated, by treatment with antagonist (G-15), in testes of C57BL/6 mice: immature (3 weeks old), mature (3 months old) and aged (1.5 years old) (50 μg/kg bw), as well as MA-10 mouse Leydig cells (10 nM/24 h) alone or in combination with 17β-estradiol or antiestrogen (ICI 182,780). In G-15-treated mice, overgrowth of interstitial tissue was found in both mature and aged testes. Depending on age, differences in structure and distribution of various Leydig cell organelles were observed. Concomitantly, modulation of activity of the mitochondria and tubulin microfibers was revealed. Diverse and complex GPER regulation at the mRNA level and protein of estrogen signaling molecules (estrogen receptor α and β; ERα, ERβ and cytochrome P450 aromatase; P450arom) in G-15 Leydig cells was found in relation to age and the experimental system utilized (in vivo and in vitro). Changes in expression patterns of ERs and P450arom, as well as steroid secretion, reflected Leydig cell heterogeneity to estrogen regulation throughout male life including cell physiological status.We show, for the first time, GPER with ERs and P450arom work in tandem to maintain Leydig cell architecture and supervise its steroidogenic function by estrogen during male life. Full set of estrogen signaling molecules, with involvement of GPER, is crucial for proper Leydig cell function where each molecule acts in a specific and/or complementary manner. Further understanding of the mechanisms by which GPER controls Leydig cells with special regard to male age, cell of origin and experimental system used is critical for predicting and preventing testis steroidogenic disorders based on perturbations in estrogen signaling.</jats:p

Analysis of ghrelin expression in mouse skeletal muscles

Grelina jest hormonem zaliczanym do klasy hormonów peptydowych wykazujących wielokierunkowe działanie w organizmie. Za produkcję i uwalnianie tego hormonu odpowiada głównie żołądek, ale jej obecność stwierdzono także w przysadce mózgowej, trzustce, gonadach i mięśniach szkieletowych. Dotychczasowe badania nad wpływem greliny na mięśnie szkieletowe opierały się głównie na analizie ustalonych linii komórkowych takich jak C2C12 i i28. Celem niniejszej pracy było określenie profilu ekspresji greliny w wolnych i szybkich typach mięśni szkieletowych to jest w mięśniu Soleus (SOL), Gastrocnemius (GAS), Extensor digitorum longus (EDL) oraz Tibialis anterior (TA) w trakcie rozwoju osobniczego myszy. Zbadano również profil ekspresji greliny w mięśniach regenerujących po uszkodzeniu mechanicznym oraz chemicznym mięśni. Na podstawie analizy znakowania immunofluorescencyjnego stwierdzono, iż grelina ulega ekspresji w wolnych włóknach mięśniowych i najprawdopodobniej pełni rolę stabilizatora włókien wolnokurczliwych. Co więcej, ekspresję greliny odnotowano już w 14-tym dniu po urodzeniu w wolnych włóknach mięśniowych co sugeruje, że hormon ten jest obecny już w bardzo młodych mięśniach i utrzymuje się stale w trakcie rozwoju w dorosłych mięśniach szkieletowych. Obecność tego hormonu zidentyfikowano także w mięśniach regenerujących po uszkodzeniu.Ghrelin is a hormone classified as a peptide hormone, which has a multi-directional action in the body. For the production and release of this hormone is primarily responsible stomach, but ghreline was also found in the pituitary gland, pancreas, skeletal muscle, and gonads. Previous studies on the effect of ghrelin on skeletal muscles are mainly based on the analysis of established cell lines such as C2C12 and i28. The purpose of this study was to determine the expression profile of ghrelin in the slow and fast types of skeletal muscle in the Soleus muscle (SOL), Gastrocnemiu (GAS), Extensor digitorum longus (EDL) and Tibialis anterior (TA) during the ontogenetic development of the mouse. The expression profile of ghrelin was also studied in muscle regeneration after chemical or mechanical muscle injury. Based on the analysis of immunofluorescence labeling there was found that ghrelin is expressed in the slow muscle fibers and most probably stabilizes the phenotype of slow-contractile muscle fibers. Furthermore, the expression of ghrelin was already noted in the 14th day after birth, which suggests that ghrelin has been already expressed in very young muscles and is maintained during further development of muscle. The presence of the hormone has also been identified in muscle regeneration after injury

The role of selected neurotrophins in the development and regeneration of skeletal muscle

Czynniki neurotroficzne są niezbędne do prawidłowego rozwoju mięśnia szkieletowego jak i prawidłowej regeneracji mięśnia po urazie. Praca zawiera opis budowy mięśnia szkieletowego oraz ekspresji neurotrofin i ich receptorów: p75 i TRK. Scharakteryzowano wybrane neurotrofiny tj. czynnik neurotroficzny pochodzenia mózgowego (BDNF), czynnik neurotroficzny pochodzenia glejowego (GDNF), czynnik wzrostu nerwów (NGF), neurotrofinę-3 (NT-3) oraz neurotrofinę-4/5 (NT-4/5). Ponadto opisano wpływ, jaki wywierają na sygnalizację w rejonie połączenia nerwowo-mięśniowego. Zebrane dane literaturowe przedstawione w formie wykresów jak i rycin wskazują na ważną rolę neurotrofin nie tylko w początkowych etapach rozwoju mięśnia szkieletowego, ale także w dorosłym mięśniu szkieletowym pobudzając komórki satelitarne do prawidłowego różnicowania. Przedstawiono także, jak obecność neurotrofin może zapobiec zmianom patologicznym w wybranych dystrofiach mięśniowych.Neurotrophic factors are essential for normal development of skeletal muscle and normal muscle regeneration after injury. This paper describes organization of the skeletal muscle, expression of neurotrophins and their receptors: p75 and TRK. Selected neurotrophins such as brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), nerve growth factor (NGF), neurotrophin-3 (NT-3) and neurotrophnin-4/5 (NT-4/5) has been characterized. Moreover, a description of the impact they have on signaling in the neuromuscular junction has been included. Collected literature data presented here in the form of graphs and figures indicated an important role of neurotrophins not only in the early stages of development, but also in the adult muscle satellite cells by stimulating them for normal differentiation. It is also shown how the presence of neurotrophins can prevent the pathologic changes in some muscular dystrophies