Exposure to air pollution affects central nervous system and leads to neuroinflammation and neurodegeneration. The aim of this study was to evaluate the effect of aerobic exercise and carbon black exposure on TLR4 and TLR2 mRNA gene expression in the hippocampus of rats.24 male Wistar rats were randomly assigned to 4 groups: A: control, B: exposure to pollution, C: exercise, D: exercise-pollution. B and D groups were exposed to PM10 carbon black for 4 weeks. The D and C groups carried out aerobic exercise program with 50% of their own maximal speed (60 minutes per session) after each session of pollution. The mRNA gene expression of TLR4 and TLR2 were analyzed in hippocampus tissue of rats by Real time – PCR. In order to determine the significance of the effect of exercise and pollution, two-way ANOVA test was used. Carbon black air pollution significantly increased TLR4 (P=0.005) and TLR2 (P=0.033) mRNA gene expression. The exercise had no significant effect on the mRNA gene expression of TLR4 (P=0.137) and TLR2 (P=0.113). The exercise following an exposure to polluted air had no significant effect on mRNA gene expression of TLR4 (P=0.063) and TLR2 (P=0.867) in hippocampus tissue of male rats. Also, the exercise was associated with a significant decrease in body mass in carbon black exposed groups. It seems that aerobic exercise reduces TLR4 and TLR2 in hippocampus tissue of rats after an exposure to polluted air and may be able to moderate the neuroinflammatory effects resulted from pollution.

Background: Recently, reports have indicated a role for the membrane form of Toll-like Receptor 2 (TLR2) in asthma pathogenesis. In this study we examined soluble TLR2 levels in serum and sputum of asthmatic and healthy subjects. Methods: Serum and sputum samples were obtained from 33 asthmatic and 19 healthy subjects. The asthmatics were classified into four groups according to the Global Initiative for Asthma. A sandwich ELISA was developed to measure soluble TLR2 (sTLR2) in serum and sputum. TLR2 mRNA expression was determined by semi-quantitative RT-PCR of all sputum samples. Results: The mean sTLR2 levels from serum and sputum of asthmatics were significantly lower than those from healthy subjects. Moreover, sTLR2 concentration decreased concomitantly with asthma severity. The differences observed, however, were not statistically significant. TLR2/GAPDH mRNA of sputum leukocytes was also significantly lower in asthmatics than in healthy subjects.Conclusion: This study demonstrated for the first time thatsTLR2 levels are lower in serum and sputum samples from asthmatic than from healthy subjects, and this could be an indicator of TLR2 expression. We also found that sTLR2 concentration in serum decreased concomitantly with an increase of asthma severity clinical score.

Introduction. Emodin, an anthraquinone derivative from the Chinese herb Radix et Rhizoma Rhe, has been reported to possess anti-inflammatory property in vivo and in vitro. However, the effect of emodin on inflammation in lipopolysaccharide (LPS)-induced acute kidney injury as an immunomodulator has yet to be determined. This study aimed to investigate whether emodin had protective effects against LPS-induced acute kidney injury by inhibiting toll-like receptor 2 (TLR2) signal pathway in normal rat kidney epithelial cells (NRK-52E). Materials and Methods. The NRK-52E cells were incubated with LPS with and without the indicated concentrations of emodin for 24 hours. The TLR2 and NF-κ B protein level was detected by Western blot method. Tumor necrosis factor (TNF)-α , interleukin (IL)-1β , and IL-6 protein levels were measured using an enzymelinked immunosorbent assay. The mRNA expression of TLR2, NF-κ B, TNF-α , IL-1β , and IL-6 was detected using a real-time polymersase chain reaction. Results. A concentration of 102 ng/mL of LPS significantly upregulated mRNA and protein levels of TLR2 and NF-κ B and increased TNF-α , IL-1β , and IL-6 mRNA and protein levels. At doses of 20 μ M and 40μ M, emodin was able to inhibit LPS-induced TLR2, NF-κ B, TNF-α , IL-1β and IL-6 mRNA and protein expressions in cultured NRK-52E cells. Conclusions. These results demonstrate that an elevated expression of inflammatory cytokines and TLR2 in cells stimulated by LPS were simultaneously inhibited by emodin. Therefore, emodin attenuates the inflammation by inhibiting TLR2-mediated NF-κ B signal pathway, which may contribute to the immune inflammation regulation of emodin in LPS-induced acute kidney injury.

Our previous study reported that Lactobacillus acidophilus (L. acidophilus) key laboratory of dairy science (KLDS) 1. 0738 had an effective impact on inhibiting β-lactoglobulin (β-lg) allergy. This study further investigated the anti-allergic activity of peptidoglycan (PGN) isolated from KLDS 1. 0738. This study aimed to assess whether toll-like receptor 2 (TLR2)/NF-kappaB (NF-κ B) signaling activated by PGN was responsible for reducing allergic inflammation. We first examined the role of PGN on cytokine production and TLR2 signaling expression of macrophages. Then the immunoregulatory capacity of PGN was further evaluated by adopting the β-lg-sensitized mice model. The levels of sera IgE, regulatory T cells (Treg) and T-helper (Th) 17-related cytokine were detected by ELISA. TLR2 signaling mRNA and protein expression in colon tissues were measured by quantitative RT-PCR and western blot, respectively. Our data showed that administration of L. acidophilus PGN inhibited IgE production and improved the Treg/Th17 balance toward a Treg response in a mouse model of β-lg allergy. In addition, treating different doses L. acidophilus PGN to sensitized mice significantly increased TLR2 levels, along with enhancing NF-κ B expression, especially in medium and high concentration (p<0. 05). Further analysis revealed that the mRNA expression of TLR2 and NF-κ B were positively correlated with the Foxp3 mRNA expression (p<0. 05), but were negatively correlated with the RORγ t mRNA expression in L. acidophilus PGN-treated group compared to allergy group (p<0. 05). This study suggests PGN was similar to probiotics in preventing β-lg allergy through regulating Treg/Th17 imbalance, and activation of TLR2/NF-κ B signaling may be involved in this process.

Background: Hepatitis C virus (HCV) is an important human pathogen affecting an estimated 120 – 170 million individuals in the world. Toll-Like receptors (TLRs) are pattern-recognition receptors that recognize pathogen-associated molecular patterns, and stimulate immune responses.Objectives: The aim of this study was to determine the mRNA expression level of TLR2 and TLR7 in HCV-infected patients in comparison with normal controls.Patients and Methods: Nineteen consecutive patients with HCV infection and nineteen sex and age-matched healthy controls were studied in a case-controlled research.Results: Our results showed that the expressions of TLR7 in HCV infected samples were significantly increased in comparison those of the controls (P = 0.02), while the expression of TLR2 was similar between the case and the control group (P = 0.8). There were no associations between the expression levels of TLR2 and TLR7 with HCV viral load and HCV genotypes. Also, there was no association between viral load and genotypes of the virus.Conclusions: Our findings showed that HCV infection could lead to increased expression level of TLR7 mRNA in peripheral blood cells of HCV infected samples. The viral load and genotypes of HCV did not affect the mRNA expression levels of TLR2 and TLR7.

Background: Paroxetine is one of the well-known antidepressants. Recent studies have focused on paroxetine’ s probable immuno-modulatory effects, since findings have indicated inflammation’ s role in the pathophysiology of depression. Therefore, in the present study, TLR2 and TLR4 mRNA genes expression was assessed in paroxetinetreated peripheral blood mononuclear cells (PBMCs). Methods: Venous blood samples were drawn from five healthy men (20-40 years old). Peripheral blood mononuclear cells (PBMCs) were isolated from samples and were cultured. After the first incubation for 24h, phytohemagglutinin plus lipopolysaccharide were added to the cells and then were incubated for 24h. Thereafter, cells were treated with different concentrations of paroxetine in the presence or absence of inhibitors of 5-HT2 and 5-HT7 receptors. After incubation for 48h, RNA was extracted and cDNA was synthesized. Using the real-Time PCR technique, TLR2 and TLR4 genes mRNA expression were evaluated. Statistical analysis of data were carried out using GraphPad Prism 7. Results: TLR2 and TLR4 mRNA expression were significantly increased in response to paroxetine at all concentrations. Furthermore, the co-culture of cells with the drug and the 5-HT2R and 5HT7R inhibitor simultaneously revealed that paroxetine’ s immuno-modulatory effects via TLR2 are dependent on serotonin, while it is independent of serotonin in the case of TLR4. Conclusion: Considering paroxetine’ s effect in modulating immune responses via increasing TLR2 and TLR4 expression, paroxetine could have therapeutic potentials in diseases with a deficiency in these receptors.

Objective(s): Stroke is known as a main cause of mortality and prolonged disability in adults. Both transient receptor potential V1 (TRPV1) channels and toll-like receptors (TLRs) are involved in mediating the inflammatory responses. In the present study, the effects of TRPV1 receptor activation and blockade on stroke outcome and gene expression of TLR2 and TLR4 were assessed following permanent middle cerebral artery occlusion in rats Materials and Methods: Eighty male Wistar rats were divided into four groups as follows: sham, vehicle, AMG9810 (TRPV1 antagonist) -treated and capsaicin (TRPV1 agonist) -treated. For Stroke induction, the middle cerebral artery was permanently occluded and then behavioral functions were evaluated 1, 3 and 7 days after stroke.Results: TRPV1 antagonism significantly reduced the infarct volume compared to the stroke group. Also, neurological deficits were decreased by AMG9810 seven days after cerebral ischemia. In the ledged beam-walking test, the slip ratio was enhanced following ischemia. AMG9810 decreased this index in stroke animals. However, capsaicin improved the ratio 3 and 7 days after cerebral ischemia. Compared to the sham group, the mRNA expression of TLR2 and TLR4 was significantly increased in the stroke rats. AMG9810 Administration significantly reduced the mRNA expression of TLR2 and TLR4. However, capsaicin did not significantly affect the gene expression of TLR2 and TLR4.Conclusion: Our results demonstrated that TRPV1 antagonism by AMG9810 attenuates behavioral function and mRNA expression of TLR2 and TLR4. Thus, it might be useful to shed light on future therapeutic strategies for the treatment of ischemic stroke.

Vaccination is one of the important approaches in the prevention and control of diseases. Although the capacity to present antigens other than the disease-specific antigen in the traditional vaccine composition provides a potential benefit by increasing its protective efficacy, many components that are not needed for the related disease are also transferred. These components can reduce vaccine activity by lowering immunity against protective antigens. The reasons such as the low effectiveness of traditional vaccines and the high cost of production and time-consuming reasons show that it is necessary to develop a new vaccine method for our world, which is struggling with epidemics almost every year. Among nucleic acids, mRNA has many advantages, such as genomic integration, induction of anti-DNA autoantibodies, and immune tolerance induced by long-term antigen expression. mRNA vaccines have become a therapeutic target for reasons such as efficacy, safety, fast and non-expensive production. The fact that mRNA triggers both humoral and cellular immunity and goes only to the cytoplasm, not to the nucleus, makes it highly efficient. The mRNA must cross the lipid bilayer barrier and entry to the cytoplasm where it is translated into protein. There are two main ways of mRNA vaccine delivery for this: ex vivo loading of mRNA into dendritic cells (DCs) and direct injection of mRNA with or without a carrier. Studies continue to understand which delivery system is therapeutically more efficient. Preclinical and clinical trials showed that mRNA vaccines trigger a long-lasting and safe immune response.

Objective: Gastrointestinal (GI) tract, like other mucosal surface, is colonized with a microbial population known as gut microbiota. Outer membrane vesicles (OMVs) which are produced by gram negative bacteria could be sensed by Toll like receptors (TLRs). The interaction between gut microbiota and TLRs affects homeostasis and immune responses.In this study, we evaluated TLR2, TLR4 genes expression and cytokines concentration in Caco-2 cell line treated with Bacteroides fragilis (B. fragilis) and its OMVs.Materials and Methods: In this experimental study, OMVs were extracted using sequential centrifugation and their physicochemical properties were evaluated as part of quality control assessment. Caco-2 cells were treated with B.fragilis and its OMVs (180 and 350 mg/ml). Quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) was performed to assess TLR2 and TLR4 mRNA expression levels. Pro-inflammatory (IFNg) and anti-inflammatory (IL- 4 and IL-10) cytokines were evaluated by ELISA.Results: B. fragilis significantly decreased TLR2 and slightly increased TLR4 mRNA levels in Caco-2 cell line. The TLR2 mRNA level was slightly increased at 180 and 350 mg/ml of OMVs. Conversely, the TLR4 mRNA level was decreased at 180 mg/ml of OMVs, while it was significantly increased at 350 mg/ml of OMVs. Furthermore, B. fragilis and its OMVs significantly increased and decreased IFNg concentration, respectively. Anti-inflammatory cytokines were increased by B. fragilis and its OMVs.Conclusion: B. fragilis and its OMVs have pivotal role in the cross talk between gut microbiota and the host especially in the modulation of the immune system. Based on the last studies on immunomodulatory effect of B. fragilis derived OMVs on immune cells and our results, we postulate that B. fragilis derived OMVs could be possible candidates for the reduction of immune responses.