17 Beta-Estradiol–Stimulated Nitric Oxide Production by Neutrophils

Sexual Dimorphism in Alternative Metabolic Pathways of L-Arginine in Circulating Leukocytes in Young People with Type 1 Diabetes Mellitus

Background: Sexual dimorphism in specific biochemical pathways and immune response, underlies the heterogeneity of type 1 diabetes mellitus (T1DM) and affects the outcome of immunotherapy. Arginase and nitric oxide (NO) synthase (NOS) metabolize L-arginine and play opposite roles in the immune response and autoimmune processes.Objective: We hypothesized that the above mentioned enzymes can be involved in sex and age differences in T1DM and its treatment. Based on this, the enzymes have been studied in peripheral blood leukocytes (PBL) and plasma of young people with T1DM.Methods: Patients were recruited from Muratsan University Hospital (Yerevan, Armenia) and were divided into groups: girls and boys by age, from children to adolescents and adolescents/young adults with recent-onset T1DM (RO-T1DM) (0.1-1 years) and long-term T1DM (LT-T1DM) (1.6-9.9 years). Arginase activity was assessed by L-arginine-dependent production of L-ornithine, and the NOS activity was assessed by NO/nitrite production. Glycemic control was assessed using hemoglobin A1c test. Plasma HbA1c concentration below 7.5% (median (range) 6.7 [6.2-7.5]) was taken as good glycemic control (+) and above 7.5% (median (range) 10.5 [7.6-13]) as poor glycemic control (-). Healthy volunteers with corresponding sex and age were used as the control group.Results: All the patients with RO-T1DM, with poor glycemic control, had increased arginase activity in the cytoplasm (cARG) and mitochondria (mARG) in PBL. In girls with RO-T1DM, with good glycemic control, the subcellular arginase activity decreased, and normalized in LT-T1DM, regardless of age. In contrast, boys from both age groups showed high arginase activity, regardless of glycemic control and duration of T1DM along with insulin therapy. At the same time, a significant decrease in the subcellular production of bioavailable NO was observed in children/preadolescents, regardless of glycemic control and duration of diabetes. In adolescents/young adult boys with RO-T1DM, with (-), the subcellular production of NO decreased significantly, and with LT-T1DM, the decrease was attenuated, but even with (+) remained lower than in healthy people. In contrast, in the group of same age girls with RO-T1DM, NO production increased above normal in both cellular compartments, while with LT-T1DM it normalized in the cytoplasm. In adolescents/young adults with LT-T1DM, NO production in PBL mitochondria decreased by almost a half, regardless of glycemic control and gender. Changes in the metabolic pathways of L-arginine in plasma differed and were less substantial than in the PBL cellular compartments in T1DM.Conclusions: Glycemic status and duration of T1DM along with insulin therapy affect the activity of arginase and NOS-dependent production of bioavailable NO in the cytoplasm and mitochondria in PBL of young patients with T1DM, depending on sex and age. Arginase and NOS can directly affect the processes occurring in the pancreas and the outcome of therapy through infiltrated leukocytes. Obtained data can be useful for understanding the heterogeneity of T1DM and using it to develop available criteria for assessing the severity and treatment of autoimmune diabetes.

Immune Tumor Microenvironment in Breast Cancer and the Participation of Estrogen and Its Receptors in Cancer Physiopathology

Breast cancer is characterized by cellular and molecular heterogeneity. Several molecular events are involved in controlling malignant cell process. In this sense, the importance of studying multiple cell alterations in this pathology is overriding. A well-identified fact on immune response is that it can vary depend on sex. Steroid hormones and their receptors may regulate different functions and the responses of several subpopulations of the immune system. Few reports are focused on the function of estrogen receptors (ERs) on immune cells and their roles in different breast cancer subtypes. Thus, the aim of this review is to investigate the immune infiltrating tumor microenvironment and prognosis conferred by it in different breast cancer subtypes, discuss the current knowledge and point out the roles of estrogens and its receptors on the infiltrating immune cells, as well as to identify how different immune subsets are modulated after anti-hormonal treatments in breast cancer patients.