In 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.

Deficiency of estradiol during the menopausal period is an important risk factor for neurodegenerative diseases, including various optic neuropathies. The aim of this study was to evaluate the impact of surgical menopause on the function and survival ratio of RGCs in the rat model of ONC (optic nerve crush). We used eight-week-old female Long Evans rats, divided into two main groups depending on the time between ovariectomy procedure (OVA) and euthanasia (two weeks vs. seven weeks), and subgroups—OVA, OVA + ONC, or ONC. Retinal function was assessed with electroretinography (ERG). RGC loss ratio was evaluated using immunolabelling and counting of RGCs. Seven weeks after OVA, the menopause morphologically affected interneurons but not RGC; however, when the ONC procedure was applied, RGCs appeared to be more susceptible to damage in case of deprivation of estrogens. In our analysis, PhNR (photopic negative responses) were severely diminished in the OVA + ONC group. A deprivation of estrogens in menopause results in accelerated retinal neurodegeneration that firstly involves retinal interneurons. The lack of estrogens increases the susceptibility of RGCs to insults.

Introduction: Prostaglandin analogs are the first line of treatment in patients with glaucoma. Recently, many preservative-free prostaglandin analogs have been marketed to increase their tolerance in chronic use. However, potentially safer formulations have been reported to induce inflammation within ocular surface and adnexa, associated with pronounced activation of tissue macrophages. Aim: We aimed to evaluate the effect of a Stearoyl-CoA desaturase-1 (SCD1) inhibitor, MF-438, on the differentiation of monocytes exposed to eye drop detergents, representing saturated fatty acid derivatives. Methods: A culture of human peripheral blood monocytes was exposed to eye drops containing fatty acid derivatives (eye drop detergents), pf-latanoprost (Monoprost^®, hydroxystearate macrogolglycerol – MGHS40) or pf-tafluprost (Taflotan^®, polysorbate 80 – PS80), as well as pf-latanoprost+MF-438, MGHS40, and PS80. For the negative control C(-), monocytes were cultured in basal medium, and for the positive controls, monocytes were stimulated with Lipopolysaccharide (LPS) and Interferon γ (IFNγ) (M1 macrophages) or Interleukin-4 (IL-4) (M2 macrophages). The concentration of desaturase in the cell homogenates was determined by ELISA. The number of cells was counted under a microscope at 20x magnification. Results: The following concentrations of SCD1 (ng/mL) were measured: 7.8± 0.3 – pf-latanoprost group; 1.5± 0.4 – pf-tafluprost group; 6.8± 0.7 – MGHS40 group; 0.4± 0.002 – PS80 group; 0.9± 0.02 – pf-latanoprost+MF-438 group; 5.4± 1.6 – C(-) control; 0.5± 0.04 – M1 control; 2.2± 0.13 – M2 control. The percentages of macrophages in culture were 33.6%, 17.6%, 33%, 0%, 13.5%, 18.6%, 36.3%, and 39.3% for the pf-latanoprost, pf-tafluprost, MGHS40, PS80, pf-latanoprost+MF-438, C(-), M1, and M2 cultures, respectively. There was a strong correlation between SCD1 concentration and macrophage count in the culture (r=0.8, p< 0.05). Conclusion: Inhibition of SCD1 in monocytes prevents their transformation into macrophages after exposure to saturated fatty acid derivatives contained in eye drops, which may contribute to the limitation of latent inflammation within ocular adnexa and could possibly translate into better tolerability of the topical treatment.