Quinic acid ameliorates ulcerative colitis in rats, through the inhibition of two TLR4-NF-κB and NF-κB-INOS-NO signaling pathways.

OBJECTIVE: In this study, the therapeutic effect of quinic acid (QA), which has anti-inflammatory activity, was investigated on acetic acid-induced colitis in male Wistar rats. METHODS: Ulcerative colitis (UC) was induced in rats by acetic acid intrarectally, and the protective effects of QA in 10, 30, 60, and 100 mg/kg doses were investigated. Rats were treated for 5 days and their colon tissues were dissected out at the end. Macroscopic and histopathological examinations were performed in colon tissues. Also, the expression of inflammatory and apoptotic genes, including TLR4, IL-1ß, INOS, IL-6, TNF-α, NF-κB, Caspase-3, Caspase-8, Bax, and Bcl-2, was measured. Biochemistry indices, such as malondialdehyde (MDA) and nitrite oxide (NO) content, in addition to, total antioxidant capacity (TAC), superoxide dismutase (SOD), catalase (CAT), and enzymes activities were also assessed. RESULTS: Colitis increased the levels of MDA and NO, and enhanced the inflammatory and apoptotic gene expressions, while reducing the SOD and CAT enzymes activity, and TAC levels in the colitis rats. Also, results showed that colitis was associated with the infiltration of inflammatory cells, epithelium damage, and edema in colon tissue. QA significantly ameliorated histopathological indices, oxidative stress, inflammation, and apoptosis in colitis rats. CONCLUSION: QA ameliorated UC through the inhibition of two TLR4-NF-κB and NF-κB-INOS-NO signaling pathways, which results in the reduction of colitis complications, including oxidative stress, inflammation, apoptosis and histopathological injuries in rats. Therefore it can be concluded, that QA exerts its therapeutic effects through antiapoptotic, antioxidant, and anti-inflammatory properties.

The expression analysis of IL-6, IL-18, IL-21, IL-23, and TGF-ß mRNA in the nasal mucosa of patients with Allergic rhinitis.

Background: The profile of inflammatory and suppressing cytokines is important to contribute to the disruption of TH1/TH2 balance in Allergic rhinitis (AR). Objective: This study aimed to assess the expression levels of IL-6, IL-18, IL-21, IL-23, and TGF-ß in nasal biopsies in AR patients and evaluate its correlation with the severity of AR. Material and method: The study included 30 patients with mild persistent allergic rhinitis (MPAR), patients with moderate-to-severe (M/S) PAR, and 30 healthy individuals. The biopsies of nasal inferior turbinate mucosa were collected from each participant. The expression of IL-6, IL-18, IL-21, IL-23, and TGF-ß was evaluated by the quantitative real-time polymerase chain reaction. The degree of eosinophil infiltration into the nasal mucosa, blood eosinophils, and total serum IgE level were also measured. Result: The expression of IL-6, IL-18, and IL-23 in patients with AR significantly increased compared to the control group. Conversely, the gene expression of the TGF-ß declined in the M/S PAR group rather than the AR- group. The data did not show a significant difference in the expression of the IL-21 gene between AR+ and AR- groups. Conclusion: We suggested that inflammatory cytokines including IL-6, IL-18, and IL-23 may be involved in the severity of AR and associated with markers of inflammation.

The protective effects of resveratrol on ulcerative colitis via changing the profile of Nrf2 and IL-1ß protein.

Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) with increasing incidence and prevalence in developed countries. The presence of inflammatory cytokines is considered the main detrimental factor in severe types of IBD. The Nrf2 transcription factor plays an important role in reducing the expression of inflammatory agents such as interleukin (IL)-1ß and increasing reparative factors such as IL-11. Resveratrol, a plant-derived phenolic compound, reduces the damage in chronic experimentally induced colitis. Twenty patients with UC and also 20 healthy controls were recruited in this study. The proteins expression of Nrf2 and IL-1ß was assessed in colonic biopsies by Western blotting. Caco-2 cells were challenged with TNF-α (in vitro simulation of UC), in the presence or not of 190 nM (24 h) and 75 nM (48 h) Resveratrol. Then, Nrf2 and IL-1ß in gene and protein expression were measured by real time-PCR and Western blotting in different treatments. Finally, IL-11 proteins expression was measured in culture supernatant by ELISA. A significant increase of IL-1ß protein was detected in inflamed colonic tissues from UC patients compared with the control individuals. In Caco-2 cells challenged with TNF-α, protein expression of IL-1ß and p-Nrf2 showed an increase, while gene expression of Nrf2 did not show a significant difference. After treatment with Resveratrol, both IL-1ß mRNA and protein levels were reduced, while IL-11 protein levels showed any increase. The p-Nrf2 is a dominant form which is prevalent in inflamed tissues from UC patients. Resveratrol can reverse the inflammatory effects of TNF-α by reducing IL-1ß and increasing IL-11 production.

Possible involvement of PI3K/AKT/mTOR signaling pathway in the protective effect of selegiline (deprenyl) against memory impairment following ischemia reperfusion in rat.

Short-term cerebral ischemia led to memory dysfunction. There is a pressing need to introduce effective agents to reduce complications of the ischemia. Involvement of PI3K/AKT/mTOR signaling pathway has been determined in the neuroprotective effect of various agents. Selegiline (deprenyl) possessed neuroprotective properties. In this study global ischemia/reperfusion was established in rats. Selegiline (5 mg/kg for 7 consecutive days) administrated via intraperitoneal route. Possible involvement of PI3K/AKT/mTOR signaling pathway was evaluated using qRT-PCR, immunohistochemistry and histophatologic evaluations in the hippocampus. Spatial memory was evaluated by morris water maze (MWM). Results showed that ischemia impaired the memory and ischemic rats spent more time to find hidden platform in the MWM. Ischemia significantly decreased levels of PI3K, AKT and mTOR in the hippocampus. Histopathologic assessment revealed that the percent of dark neurons significantly increased in the CA1 area of the hippocampus of ischemic rats. Selegiline improved the memory as ischemic rats spent fewer time to find hidden platform in the MWM. Findings showed that selegiline increased the level and expression of PI3K, AKT and mTOR as well as decreased the proportion of dark neurons in the CA1 area of the pyramidal layer of the hippocampus. We concluded that selegiline, partially at least, through increases the expression of PI3K, AKT and mTOR as well as decreases the percent of dark neurons in the hippocampus could improve the memory impairment following the ischemia in rats.

The Role of Inflammatory Cytokines in Creating T Cell Exhaustion in Cancer.

Secreted inflammatory cytokines are considered as critical mediators in the tumor microenvironment. Cancer cells play a significant role in the differentiation of effector T cells to exhausted T cells through mediator production. Effector T cells that undergo tumor microenvironment become terminally differentiated into exhausted T cells. These changes create an opportunity for tumorigenesis and invasion of cancer cells. Despite having some characteristics of effector T cells, the exhausted T cells lose their antitumor properties. In this article, the phenotypes and function of exhausted T cells were reviewed and the expression pattern of inflammatory cytokines in tumor tissues and peripheral blood of cancer patients were described. Additionally, the effects of inflammatory cytokines on intracellular factors and signals of T lymphocyte cells were explained. In conclusion, the authors referred to probable approaches that could be used to improve the antitumor activity of T cells and intervention into T cell exhaustion.

The regulatory role of Nrf2 in antioxidants phase2 enzymes and IL-17A expression in patients with ulcerative colitis.

BACKGROUND: Reactive oxygen species (ROS) is one of the pathogenic factors responsible for intestinal injury in Ulcerative colitis (UC). Nuclear factor erythroid-2 related factor 2 (Nrf2) plays a critical role against ROS factors to conserve epithelial integrity. This study aimed to localize Nrf2 and IL-17A protein in the inflamed mucosa of patients with ulcerative colitis. The gene expression of Nrf2 was also correlated with GST-A4 and PRDX1. MATERIALS AND METHODS: A total of 20 patients and 20 healthy controls with definite UC based on the clinical criteria were enrolled for this study. The expression pattern of Nrf2 and IL-17A protein was compared in inflamed and non-inflamed colonic biopsies by immunohistochemical staining. Nrf2, GST-A4 and PRDX1 gene expression were determined by real-time polymerase chain reaction (RT-PCR). RESULTS: In inflamed colonic biopsies, an increased level of Nrf2 protein factor was detected in epithelial cells. Conversely, IL-17A protein was presented more in mononuclear cells in mucosa and lamina propria regions. A significant increase of Nrf2, GST-A4 gene expression was observed in both mild and severe patients with ulcerative colitis. GST-A4 gene expression indicated a high exponential rate in logistic regression. CONCLUSION: Oxidative stress in inflamed colonic tissue can induce Nrf2 gene expression. The performance of Nrf2 transcription factor may lead to the induction of GST-A4 and PRDX1. IL-17A is less detected in intestinal inflammation, presenting Nrf2 factor. The present findings suggest that Nrf2 function in the gut plays a role in arresting both inflammatory response and oxidative damages of UC.

Intensified Th9 Response is Associated with the Immunopathogenesis of Active Ulcerative Colitis.

BACKGROUND: Ulcerative colitis (UC) is a chronic inflammatory disorder of the large intestine histologically characterized by indistinct sustained inflammatory responses. Genetical susceptibility and environmental factors' effects play the roles in disease occurrence and it can be life threatening if remains untreated. It seems that intensification of inflammatory responses in this condition is not restricted to a specific cell line of T lymphocytes. Our aim was to determine the number of T helper 9 (Th9) cells in inflamed colonic biopsies of UC patients. We also correlated it with interleukin (IL)-9 protein level in addition to certain genes expressions associated with Th9 phenotype. METHODS: Expression of CD4 and IL-9 were evaluated by immunohistochemical staining. Enzyme linked immunosorbent assay (ELISA) was performed to determine the colonic expression of IL-9 protein and finally mRNA expressions of interferon regulatory factor 4 (Irf4), Smad2, and Smad3 were measured by real-time polymerase chain reaction (RT-PCR) as critical transcription factors of Th9 differentiation. RESULTS: Number of Th9 cells was significantly increased in inflamed samples as compared with normal tissues. Also quantitative measurement of IL-9 by ELISA and mRNA expressions of Irf4, Smad2, and Smad3 showed notable correlative enhancements in patient's samples. CONCLUSION: Function and number of Th9 cells are up-regulated in the inflamed mucosa of UC patients as with the protein secretion of IL-9 and mRNA expressions of Irf4, Smad2, and Smad3, so Th9 cells and IL-9 may become remarkable therapeutic targets for IBD treatment in the future.

The expression analysis of Fra-1 gene and IL-11 protein in Iranian patients with ulcerative colitis.

BACKGROUND: Fra-1 (fosl1) belongs to the activator protein1 (AP-1) family inducing IL-11 expression in oxidative stress condition. IL-11 plays a pivotal role in protecting epithelial barriers integrity. In this study, we investigated the Fra-1 gene expression in the inflamed mucosa of patients with ulcerative colitis (UC) as well as its relation to IL-11 expression. MATERIALS AND METHODS: We enrolled 20 patients and 20 healthy controls with definite UC based on the clinical criteria. Fra-1 gene expression in inflamed and non-inflamed colonic biopsies was determined by real-time polymerase chain reaction (RT-PCR). The IL-11 protein concentration was measured by Enzyme-Linked Immunosorbent Assay (ELISA) method. Pearson correlation was applied to calculate the relation between Fra-1 and IL-11. RESULTS: An increased level of Fra-1 gene expression was observed in patients with mild ulcerative colitis. The protein concentration of IL-11 was also increased in mild UC patients. Conversely, a significant decrease of IL-11 protein level was detected in severe UC patients compared to control group. CONCLUSION: Oxidative stress in inflamed intestinal biopsies can induce fra-1 gene expression. Our findings suggest that Fra-1 transcription factor leads to the production of IL-11 protein in UC patients.