Complement 3 Receptor Expression in Individuals with Type 2 Diabetes.

BACKGROUND: According to the World Health Organization, as of 2014 9% of the world's adult population is affected by diabetes. Uncontrolled diabetes is a pro-inflammatory process that increases generation of reactive oxygen species (ROS). METHODS: The production of ROS leads to a chronic increase in oxidative stress which results in an increased susceptibility to infections. Individuals with type 2 diabetes mellitus (T2DM) are highly susceptible to Mycobacterium tuberculosis (M. tb) infection. Previous research has demonstrated that glutathione (GSH) plays an important role in the control of M. tb infection. Recent studies have demonstrated that phagocytosis of M.tb is diminished in patients with T2DM. Phagocytosis in macrophages is thought to be mediated in part by complement protein 3b (C3b)-complement protein receptor 3b (C3R) interactions. Since C3b production is not diminished in patients with T2DM we propose that C3R production is reduced and is the cause for impaired macrophage phagocytosis as well as IL-12 and IFN-γ signaling. CONCLUSION: This study utilizes a quantitative PCR (qPCR), demonstrating decreased transcription of C3R mRNA in patients with T2DM as compared to non-diabetics.

Liposomal Glutathione Supplementation Restores TH1 Cytokine Response to Mycobacterium tuberculosis Infection in HIV-Infected Individuals.

Cytokines are signaling biomolecules that serve as key regulators of our immune system. CD4(+) T-cells can be grouped into 2 major categories based on their cytokine profile: T-helper 1 (TH1) subset and T-helper 2 (TH2) subset. Protective immunity against HIV infection requires TH1-directed CD4 T-cell responses, mediated by cytokines, such as interleukin-1ß (IL-1ß), IL-12, interferon-γ (IFN-γ), and tumor necrosis factor-α (TNF-α). Cytokines released by the TH1 subset of CD4 T-cells are considered important for mediating effective immune responses against intracellular pathogens such as Mycobacterium tuberculosis (M. tb). Oxidative stress and redox imbalance that occur during HIV infection often lead to inappropriate immune responses. Glutathione (GSH) is an antioxidant present in nearly all cells and is recognized for its function in maintaining redox homeostasis. Our laboratory previously reported that individuals with HIV infection have lower levels of GSH. In this study, we report a link between lower levels of GSH and dysregulation of TH1- and TH2-associated cytokines in the plasma samples of HIV-positive subjects. Furthermore, we demonstrate that supplementing individuals with HIV infection for 13 weeks with liposomal GSH (lGSH) resulted in a significant increase in the levels of TH1 cytokines, IL-1ß, IL-12, IFN-γ, and TNF-α. lGSH supplementation in individuals with HIV infection also resulted in a substantial decrease in the levels of free radicals and immunosuppressive cytokines, IL-10 and TGF-ß, relative to those in a placebo-controlled cohort. Finally, we determined the effects of lGSH supplementation in improving the functions of immune cells to control M. tb infection by conducting in vitro assays using peripheral blood mononuclear cells collected from HIV-positive individuals at post-GSH supplementation. Our studies establish a correlation between low levels of GSH and increased susceptibility to M. tb infection through TH2-directed response, which may be relieved with lGSH supplementation enhancing the TH1 response.

Glutathione synthesis is compromised in erythrocytes from individuals with HIV.

We demonstrated that the levels of enzymes responsible for the synthesis of glutathione (GSH) such as glutathione synthase (GSS), glutamate-cysteine ligase-catalytic subunit (GCLC), and glutathione reductase (GSR) were significantly reduced in the red blood cells (RBCs) isolated from individuals with human immunodeficiency virus (HIV) infection and this reduction correlated with decreased levels of intracellular GSH. GSH content in RBCs can be used as a marker for increased overall oxidative stress and immune dysfunctions caused by HIV infection. Our data supports our hypothesis that compromised levels of GSH in HIV infected individuals' is due to decreased levels of GSH-synthetic enzymes. The role of GSH in combating oxidative stress and improving the functions of immune cells in HIV patients' indicates the benefit of an antioxidant supplement which can reduce the cellular damage and promote the functions of immune cells.