Foot-and-mouth disease virus VP3 protein acts as a critical proinflammatory factor by promoting toll-like receptor 4-mediated signaling

Foot-and-mouth disease virus (FMDV) infection in cloven-hoofed animals causes severe inflammatory symptoms, including blisters on the oral mucosa, hoof, and breast; however, the molecular mechanism underlying the inflammatory response is unclear. In this study, we provide the first evidence that the FMDV protein VP3 activates lipopolysaccharide-triggered Toll-like receptor 4 (TLR4) signaling. FMDV VP3 increased the expression of TLR4 by downregulating the expression of the lysozyme-related protein Rab7b. Additionally, Rab7b can interact with VP3 to promote the replication of FMDV. Our findings suggested that VP3 regulates the Rab7b-TLR4 axis to mediate the inflammatory response to FMDV. Importance Foot-and-mouth disease virus (FMDV) infection causes a severe inflammatory response in cloven-hoofed animals, such as pigs, cattle, and sheep, with typical clinical manifestations of high fever, numerous blisters on the oral mucosa, hoof, and breast, as well as myocarditis (tigroid heart). However, the mechanism underlying the inflammatory response caused by FMDV is enigmatic. In this study, we identified the VP3 protein of FMDV as an important proinflammatory factor. Mechanistically, VP3 interacted with TLR4 to promote TLR4 expression by inhibiting the expression of the lysozyme-related protein Rab7b. Our findings suggest that FMDV VP3 is a major proinflammatory factor in FMDV-infected hosts.

Research on the Effect of p35 for Secretion of Proinflammatory Factor and Apoptosis of Chondrocyte in Chondrocytopathic Articular Fluid

To study on the effect of transcriptional regulation factor as p35 for secretion of proinflammatory factor and apoptosis of chondrocyte in chondrocytopathic articular fluid so as to improve the chondropathy. The fifty SD rats were selected for our study. It was divided into three groups including A group (control group), B group (chondrocytopathic model group of osteoarthritis) and C group (transcriptional regulation factor as p35 intervention group. The samples were collected after intervention in sixteen weeks. The sampling position was cartilage tissue of rat leg. It was adopted for immunohistochemical inspection and histopathology examination. At the same time the synovial fluid was collected. The concentration of TNF-α and IL-6 was detected. And the expression of mRNA in gene related with apoptosis was detected. The chondrocyte morphology of rats in A group was normal. The chondrocyte was damaged and goblet cell was reduced in B group. The infiltrating inflammatory cells in C group were less than in B group from pathological results. And the goblet cells in C group was increased than in B group. The expression of TNF-α, Bax, NF-κB, IL-6: B group > C group > A group. The expression of Bcl-2: A group > C group > B group. The transcriptional regulation factor as p35 related with anti-apoptosis could regulate the level of inflammatory factor as TNF-α and IL-6 in synovial fluid and restrain the lesion and apoptosis of chondrocyte.

Substantia nigra Smad3 signaling deficiency: relevance to aging and Parkinson’s disease and roles of microglia, proinflammatory factors, and MAPK

Background Smad3 signaling is indicated to regulate microglia activity. Parkinson’s disease (PD) neurodegeneration is shown to be associated with aging and neuroinflammation. However, it remains unclear about the relationship among Smad3 signaling, aging, neuroinflammation, and PD. Methods Rats were treated with SIS3 (a specific inhibitor of Smad3, intranigal injection) and/or lipopolysaccharide (intraperitoneal injection). We investigated the effect of SIS3 and lipopolysaccharide and their mechanism of action on motor behavior and nigrostriatal dopaminergic system in the rats. Furthermore, we explored the effect of SIS3 and LPS and their potential signaling mechanism of action on inflammatory response by using primary microglial cultures. Finally, we investigated the relationship among aging, Smad3 signaling, and neuroinflammation using animals of different ages. Results Both SIS3 and lipopolysaccharide induced significant behavior deficits and nigrostriatal dopaminergic neurodegeneration in the rats compared with the vehicle-treated (control) rats. Significantly increased behavior deficits and nigrostriatal dopaminergic neurodegeneration were observed in the rats co-treated with SIS3 and lipopolysaccharide compared with the rats treated with vehicle, SIS3, or lipopolysaccharide. Furthermore, both SIS3 and lipopolysaccharide induced significant microglia activation and proinflammatory factor (IL-1β, IL-6, iNOS, and ROS) level increase in the SN of rats compared with the control rats. Significantly enhanced microglial inflammatory response was observed in the rats co-treated with SIS3 and lipopolysaccharide compared with the other three groups. For our in vitro study, both SIS3 and lipopolysaccharide induced significant proinflammatory factor level increase in primary microglia cultures compared with the control cultures. Significantly increased inflammatory response was observed in the cultures co-treated with SIS3 and lipopolysaccharide compared with the other three groups. MAPK (ERK/p38) contributed to microglial inflammatory response induced by co-treatment with SIS3 and lipopolysaccharide. Interestingly, there was decrease in Smad3 and pSmad3 expression (protein) and enhancement of neuroinflammation in the mouse SN with aging. Proinflammatory factor levels were significantly inversely correlated with Smad3 and pSmad3 expression. Conclusion Our study strongly indicates the involvement of SN Smad3 signaling deficiency in aging and PD neurodegeneration and provides a novel molecular mechanism underlying the participation of aging in PD and helps to elucidate the mechanisms for the combined effect of multiple factors in PD.

S-nitrosylation-mediated activation of a histidine kinase represses the type 3 secretion system and promotes virulence of an enteric pathogen

Vibrio parahaemolyticus is the leading cause of seafood-borne diarrheal diseases. Experimental overproduction of a type 3 secretion system (T3SS1) in this pathogen leads to decreased intestinal colonization, which suggests that T3SS1 repression is required for maximal virulence. However, the mechanisms by which T3SS1 is repressed in vivo are unclear. Here, we show that host-derived nitrite modifies the activity of a bacterial histidine kinase and mediates T3SS1 repression. More specifically, nitrite activates histidine kinase sensor VbrK through S-nitrosylation on cysteine 86, which results in downregulation of the entire T3SS1 operon through repression of its positive regulator exsC. Replacement of cysteine 86 with a serine (VbrK C86S mutant) leads to increased expression of inflammatory cytokines in infected Caco-2 cells. In an infant rabbit model of infection, the VbrK C86S mutant induces a stronger inflammatory response at the early stage of infection, and displays reduced intestinal colonization and virulence at the later stage of infection, in comparison with the parent strain. Our results indicate that the pathogen V. parahaemolyticus perceives nitrite as a host-derived signal and responds by downregulating a proinflammatory factor (T3SS1), thus enhancing intestinal colonization and virulence.

Expression of IL17A in endometrial carcinoma and effects of IL17A on biological behaviour in Ishikawa cells

Objective A growing body of evidence suggests chronic inflammation triggers the process of endometrial carcinogenesis. Interleukin (IL) 17A is an important proinflammatory factor involved in the tumour angiogenesis processes of many solid tumours. This study aimed to characterize the function of IL17A in endometrioid-type endometrial carcinoma. Methods Levels of IL17A in human endometrial tissues were analysed by immunohistochemistry. In vitro proliferation and migration were analysed in Ishikawa cells treated with IL17A, using cell counting kit-8, wound healing and transwell assays. Western blots were used to analyse levels of oestrogen receptor (ER)α and ERβ proteins in Ishikawa cells treated with IL17A. Results IL17A levels were significantly higher in endometrial carcinoma tissues than in endometrial hyperplasic tissues. Significantly increased proliferation and migration was observed in Ishikawa cells treated with IL17A versus controls. Investigation of the molecular mechanism revealed that IL17A treatment upregulated the ERα/ERβ protein ratio in Ishikawa cells. Conclusions IL17A may be an important proinflammatory factor involved in promoting endometrial carcinogenesis.

An antibody against HK blocks Alzheimer’s disease peptide β-amyloid−induced bradykinin release in human plasma

Bradykinin is a proinflammatory factor that mediates angioedema and inflammation in many diseases. It is a key player in some types of hereditary angioedema and is involved in septic shock, traumatic injury, Alzheimer’s disease (AD), and stroke, among others. Activation of the plasma contact system leads to elevated levels of plasma kallikrein, which cleaves high molecular weight kininogen (HK) to release bradykinin. Drug development for bradykinin-meditated pathologies has focused on designing inhibitors to the enzymes that cleave HK (to prevent bradykinin release) or antagonists of endothelial bradykinin receptors (to prevent downstream bradykinin action). Here we show a strategy to block bradykinin generation by using an HK antibody that binds to HK, preventing its cleavage and subsequent bradykinin release. We show that this antibody blocks dextran sodium sulfate-induced HK cleavage and bradykinin production. Moreover, while the pathogenic AD peptide β-amyloid (Aβ)42 cleaves HK and induces a dramatic increase in bradykinin production, our HK antibody blocked these events from occurring. These results may provide strategies for developing treatments for bradykinin-driven pathologies.

Dihydromyricetin affects BDNF levels in the nervous system in rats with comorbid diabetic neuropathic pain and depression

Diabetic neuropathic pain (DNP) and depression (DP) are the common complications in patients with diabetes. The purpose of our research was to observe whether brain-derived neurotrophic factor (BDNF) levels and tropomyosin receptor kinase B (TrkB) in the nervous system have effects on rats with comorbid DNP and DP, and to determine whether dihydromyricetin (DHM) may influence BDNF/ TrkB pathway to mitigatethe comorbidity. The study showed that DHM treatment could attenuates pain and depressive behavior in DNP and DP combined rats. Compared with the control group, the expression level of BDNF/TrkB in the hippocampus of DNP + DP group were reduced, while the expression levels in the spinal cord and DRG were increased. However, after treatment with DHM, those changes were reversed. Compared with the control group, the level of IL-1β and TNF-α in the hippocampus, spinal cord and DRG in the DNP + DP group was significantly increased, and DHM treatment could reduce the increase. Thus our study indicated that DHM can relief symptoms of DNP and DP by suppressing the BDNF/TrkB pathway and the proinflammatory factor, and BDNF/TrkB pathway may be an effective target for treatment of comorbid DNP and DP.

2441 INTERLEUKIN-1B AND CYCLOOXYGENASE-2 PROINFLAMMATION ANALYSIS AND IN SILICO DOCKING NUCLEAR FACTOR KAPPA B ON ENDOMETRIOSIS CELL CULTURE GIVEN HEPTYL GALLATE AND OCTYL GALLATE TREATMENT

Objective: The aim of this study is to analyze the effect of octyl gallate and heptyl gallate toward the regulation of interleukin-1β and cyclooxygenase (COX)-2 proinflammatory factor on endometriosis cell culture and analyze its activity toward nuclear factor kappa B (NFkB) target protein through in silico docking technique. Methods: In vitro study was performed on endometriosis cells cultured treated with two dosages each of heptyl and octyl gallate (51.2 μg/mL and 102.4 μg/mL) for 48 h, then followed by 10 ng/mL lipopolysaccharides (LPS) induction for 24 h. The positive control group was treated by LPS induced and the negative control was treated without LPS. Inflammation regulation was evaluated with enzyme-linked immunosorbent assay technique and in silico docking analyzed using bioinformatics technique. Results: Molecular docking analysis with gallic acid and their derivatives showed that more stable affinity and stronger binding found on octyl gallate than heptyl gallate and gallic acid at the active site of NFkB. Conclusions: Based on this study results, octyl gallate and heptyl gallate were proven to be able to reduce COX-2 proinflammatory factor through NFkB pathway as an inflammatory regulator; thus, it has the potential to be developed as a therapy for endometriosis.

Impact of Mechanical Load on the Expression Profile of Synovial Fibroblasts from Patients with and without Osteoarthritis

Osteoarthritis (OA) affects the integrity of the entire joint including the synovium. The most abundant cells in the synovium are fibroblasts (SF). Excessive mechanical loading might contribute to OA pathogenesis. Here, we investigate the effects of mechanical loading on SF derived from non-OA (N-SF) and OA patients (OA-SF). We treated N-SF and OA-SF with or without mechanical loading for 48h after 24h of preincubation. Then we assessed gene and protein expression of proinflammatory factors (TNFα, COX-2, PG-E2, IL-6), extracellular matrix (ECM) components (COL1, FN1) and glycosaminoglycans (GAGs) via RT-qPCR, ELISA, DMMB assay and HPLC. Mechanical loading significantly increased TNFα and PG-E2 secretion by N-SF and OA-SF, whereas in OA-SF IL-6 secretion was reduced. COL1 and FN1 secretion were downregulated in N-SF during loading. OA-SF secreted less COL1 compared to N-SF under control conditions. In contrast, OA-SF in general expressed more FN1. GAG synthesis was upregulated in N-SF, but not in OA-SF during loading with OA-SF displaying a higher charge density than N-SF. Mechanical loading enhanced proinflammatory factor expression and GAG synthesis and decreased secretion of ECM components in N-SFs, indicating a contributing role of SF to OA development.

Inhibition study of proinflammatory factor with ethanolic extract of propolis on innate immunity from diabetes mellitus mice model

Health becomes an important topic today. One current problem was how to treat the effects of metabolic diseases, such as diabetes mellitus (DM). Thus, this study used an ethanolic extract of propolis (EEP), to test their ability as the supplement in the diabetes treatment to reduce inflammation, through proinflammatory factor response, especially nuclear factor κB (NF-κB). The streptozotocin- induced diabetes mellitus (SID) mice model was used, and expression of an proinflammatory factor was analyzed in their innate immunity cells with 3 doses of EEP, i.e. 50 mg/kg body weight, 100 mg/kg body weight, and 200 mg/kg body weight. Treatment of EEP in SID with three doses treatment decrease the number of macrophages with NF-κB expression significantly with DM control group. The results of B cells with NF-κB expression showed that EEP treatment in SID could decrease in dose 1 and dose 3, but not in dose 2. Proinflammatory cytokines expression of macrophage, especially Tumor Necrosis Factor-α and Interferon-γ, with EEP treatment in SID could decrease in three doses. This study suggests that EEP could reduce inflammation by inhibiting the development of NF-κB in innate immunity cells.