Modulatory Effects of Metformin Alone and in Combination with Cimetidine and Ibuprofen on T Cell-related Parameters in a Breast Cancer Model.

Metformin, cimetidine, and ibuprofen separately exhibit immunomodulatory and anti-tumorigenic effects. Herein, the impacts of metformin alone and in combination with cimetidine/ibuprofen on some Th1- and regulatory T (Treg) cell-related parameters were evaluated using a breast cancer (BC) model. For establishing the BC model, four groups of Balb/c mice were challenged with the carcinoma cell line. After 11-30 days post-induction, they were treated intraperitoneally (with metformin (200 mg/kg), "metformin plus cimetidine (20 mg/kg)"; "metformin plus ibuprofen (20 mg/kg)", or with all three drugs in mentioned doses. Untreated BC and without tumor mice were enrolled as control groups. On day 31, splenic Th1 and Treg cell frequencies, serum interferon-gamma (IFN-γ), and transforming growth factor-beta (TGF-ß) concentration, and intra-tumoral T-bet, TGF-ß, and forkhead box protein P3 (FOXP3) expression were measured; using flow cytometry, enzyme-linked immunosorbent assay (ELISA), and real-time-PCR, respectively. Treatment of the BC mice with metformin alone and in combination with cimetidine and/or ibuprofen enhanced the frequency of Th1 cells, and IFN-γ concentration, while it resulted in a decrease in the frequency of Treg cells, serum TGF-ß concentration, and the expression of FOXP3 and TGF-ß compared with un-treated BC mice. FOXP3 expression in the metformin-treated group was lower in mice who received combination therapy. Survival rate and body weight were increased, while tumor size and spleen index were reduced in mice treated with metformin alone and its combination with cimetidine and/or ibuprofen. No remarkable differences were found between metformin-treated mice and those who received combination therapies regarding Th1 and Treg cell percentages, TGF-ß expression, body weight, tumor size, and spleen index. The benefits of combinational therapy may be largely attributed to metformin. Immunotherapeutic potentials of metformin in cancers need further considerations.

Zingerone improves the immune responses in an animal model of breast cancer.

OBJECTIVES: The potent anti-tumorigenic effects were attributed to ginger and there are some reports regarding the anti-cancer and immunomodulatory properties ginger-derived components. This study aimed to investigate the effects of zingerone on some immune-related parameters in an animal model of breast cancer. METHODS: The breast cancer was established in female BALB/c mice using a carcinogenic 4T1 cell line. At day 10 after cancer induction, tumor-bearing mice were divided into five groups and treated intraperitoneal (daily from days 11-30) with saline or zingerone (at doses 10, 20, 50 and 100 mg/kg/day). The mice were sacrificed on day 31 and the number of splenic Th1- and Treg cells, the expression of IFN-γ and TGF-ß in the blood mononuclear cells, the antibody production against sheep red blood cell (SRBC) were determined using flow cytometry, real time-PCR and a standard hemagglutination assay, respectively. RESULTS: Zingerone at doses 50 and 100 mg/kg enhanced the number of splenic Th1 cells (p<0.03 and 0.007, respectively); at doses 10, 20, 50 and 100 mg/kg reduced the number of splenic Treg cells (p<0.02, 0.01, and 0.01, respectively), at doses 50 and 100 mg/kg enhanced the expression of IFN-γ (p<0.03), at doses 50 and 100 mg/kg reduced the expression of TGF-ß, at doses 50 mg/kg reduced the titer of anti-SRBC antibody (p<0.05). CONCLUSIONS: Zingerone improve the T cell-mediated and antibody responses in a mouse model of breast cancer. The immunotherapeutic potentials of zingerone in cancers need more considerations.

The Toll-like Receptor 2 (TLR2)-related Immunopathological Responses in the Multiple Sclerosis and Experimental Autoimmune Encephalomyelitis.

Toll-like receptors (TLRs) play principle roles in recognition of autologous components which have been pointed as the danger-associated molecular patterns (DAMP) and microbial components which are identified as pathogen associated molecular patterns (PAMP).The infiltration of various inflammatory cells such as dendritic cells, lymphocytes (CD4+ T, CD8+ T as well as B cells), monocytes and macrophages occur into the central nervous sys-tem (CNS) during multiple sclerosis (MS) and its animal model named experimental autoimmune encephalomyelitis (EAE). The infiltrated leukocytes and residential cells of the CNS express several TLRs (especially TLR2) and their expression are elevated in MS and EAE. TLR2 recognizes a large variety DAMP and PAMP molecules due to its ability to create heterodimers with TLR1, TLR6 and probably TLR10. A wide spectrum of  DAMP molecules, including heat shock protein 60 (HSP60), HSP70, high mobility group box 1 (HMGB1), ß-defensin 3, surfactant protein A and D, eosinophil-derived neurotoxin, gangliosides, serum amyloid A, hyaluronic acid and biglycan are identified by TLR2, whose their expression is increased in MS patients. TLR2 may contribute in the development of MS and EAE diseases through the reinforcement of Th1/Th17 cell-related responses, downregulation of regulatory T cells, induction of IL-17+ γδ T cells, inhibition of oligodendrocyte maturation, induction of poly ADP-ribose polymerase-1 (PARP-1)-dependent pathway in microglia, macrophages and astrocytes and inhibition of type I interferons expression. The contribution of TLR2-related immunopathological responses in the MS and EAE pathogenesis and its possible targeting as promising therapeutic potentials are considered in this review.

Leishmania species-dependent functional duality of toll-like receptor 2.

Toll-like receptors (TLRs) are a subset of pattern recognition receptors (PRR) in innate immunity and act as a connecting link between innate and adaptive immune systems. During Leishmania infection, the activation of TLRs influences the pathogen-specific immune responses, which may play a decisive role in determining the outcome of infection, toward elimination or survival of the pathogen. Antigen-presenting cells (APCs) of the innate immune system such as macrophages, dendritic cells (DCs), neutrophils, natural killer (NK) cells, and NKT cells express TLR2, which plays a crucial role in the parasite recognition and elicitation of immune responses in Leishmania infection. Depending on the infecting Leishmania species, the TLR2 pathways may result in a host-protective or a disease-exacerbating response. While Leishmania major and Leishmania donovani infections trigger TLR2-related host-protective and non-protective immune responses, Leishmania mexicana and Leishmania infantum infections are reported to elicit TLR2-mediated host-protective responses and Leishmania amazonensis and Leishmania braziliensis infections are reported to evoke a disease-exacerbating response. These findings illustrate that TLR2-related effector functions are diverse and may be exerted in a species- or strain-dependent manner. TLR2 agonists or antagonists may have therapeutic potentials to trigger the desired immune response during leishmaniasis. In this review, we discuss the TLR2-related immune responses during leishmaniasis and highlight the novel insights into the possible role of TLR2-driven resistance or susceptibility to Leishmania.

Immunomodulatory properties of cimetidine: Its therapeutic potentials for treatment of immune-related diseases.

Histamine exerts potent modulatory impacts on the cells of innate- [including neutrophils, monocytes, macrophages, dendritic cells (DCs), natural killer (NK) cells and NKT cells] and adaptive immunity (such as Th1-, Th2-, Th17-, regulatory T-, CD8+ cytotoxic T cells, and B cells) through binding to histamine receptor 2 (H2R). Cimetidine, as an H2R antagonist, reverses the histamine-mediated immunosuppression, as it has powerful stimulatory effects on the effector functions of neutrophils, monocytes, macrophages, DCs, NK cells, NKT cells, Th1-, Th2-, Th17-, and CD8+ cytotoxic T cells. However, cimetidine reduces the regulatory/suppressor T cell-mediated immunosuppression. Experimentally, cimetidine potentiate some immunologic activities in vitro and in vivo. The therapeutic potentials of cimetidine as an immunomodulatory agent were also investigated in a number of human diseases (such as cancers, viral warts, allergic disorders, burn, and bone resorption) and vaccination. This review aimed to provide a concise summary regarding the impacts of cimetidine on the immune system and highlight the cellular mechanisms of action and the immunomodulatory effects of this drug in various diseases to give novel insights regarding the therapeutic potentials of this drug for treatment of immune-related disorders. The review encourages more investigations to consider the immunomodulatory characteristic of cimetidine for managing of immune-related disorders.

The Modulatory Effects of Vitamin D on the Expression of IL-12 and TGF-ß in the Spinal Cord and Serum of Mice with Experimental Autoimmune Encephalomyelitis.

BACKGROUND & OBJECTIVE: The immunoregulatory effects of transforming growth factor (TGF)-ßand interleukin-12 (IL-12) and immunomodulatory actions of vitamin D (VD) were reported in several studies. This study aims to evaluate VD effects on IL-12 and TGF-ß expression in experimental autoimmune encephalomyelitis (EAE). METHODS: EAE was induced in three groups of C57BL/6 mice by immunization with MOG and administered intra-peritoneally 200 ngVD, PBS or olive oil (OO) from day +3 to +30. One group was also considered as healthy control group. At day 31, cytokines expression in the spinal cord and their serum levels were determined using real time-PCR and ELISA, respectively. RESULTS: IL-12 gene expression and its serum levels in PBS-injected- or OO-administrated EAE groups were significantly higher than healthy group. IL-12 gene expression in EAE group treated with VD was significantly decreased compared to PBS-injected- or OO-administrated EAE groups (P<0.001 and P<0.02, respectively). Serum IL-12 levels were significantly reduced in VD-treated EAE mice compared to PBS-injected- or OO-administrated EAE groups (P<0.004 and P<0.05, respectively). No significant difference was observed between PBS-injected-EAE, OO-administrated EAE and healthy groups regarding the expression of TGF-ß. In EAE mice treated with VD, TGF-ß expression was significantly higher than healthy group and PBS-injected EAE mice (P<0.01 and P<0.04, respectively). VD-treated EAE group had also higher serum TGF-ß levels than PBS-injected-, OO-administrated and healthy groups (P<0.05). CONCLUSION: VD modulates the expression of IL-12 and TGF-ß in spinal cord and serum of EAE mice.