Ovalbumin/lipopolysaccharide induced vasculitis in rats: a new predictive model

Author(s):  
Vandana R. Thakur ◽  
Anita A. Mehta

Abstract Objectives Currently, there are several animal models for vasculitis. Ovalbumin and lipopolysaccharide (OVA, LPS) are well established for causing inflammation and used as an adjunct in the vasculitis induction. However, to date, none has established the effect of OVA and LPS in disease induction. Therefore, in the present study, an attempt has been made to develop a new animal model for vasculitis using OVA/LPS in rats. Methods A total of 42 Wistar rats were divided randomly into seven groups (n=6/group), normal control, and three different doses (0.5, 1, and 5 mg/kg) of OVA and LPS treated groups. Half of the rats in each group received only intraperitoneal sensitization, while the remaining half rats were additionally subjected to a one-week intranasal challenge. Results Results showed that both OVA/LPS in their respective groups have significantly increased circulating inflammatory cells, C-reactive protein (CRP), Inflammatory cytokines (IL-1β, IL-6, TNF-α), Kidney damage markers (BUN, Creatinine), and liver function enzymes (AST, ALT) in a dose-dependent manner. Conclusions OVA/LPS induced vascular inflammation in a dose-dependent manner. However, the higher (5 mg/kg) dose of ovalbumin and lipopolysaccharide has contributed to severe vascular inflammation through increasing inflammatory cytokines. These findings suggest that OVA/LPS may contribute as a possible model for vasculitis in rats.

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Shuling Han ◽  
Junlan Zhou ◽  
Gangjian Qin

Background: The role of Src-associated in mitosis 68 kDa (Sam68) protein in cardiovascular biology has not been studied. A recent report suggests that Sam68 suppresses TNF-α-mediated NF-kB activation. Since NF-kB plays a critical role in vascular inflammation and injury via generation of inflammatory cytokines and recruitment of inflammatory cells, we sought to dissect the molecular mechanism by which Sam68 regulates NF-kB signaling and its functional significance during vascular injury. Methods & Results: The endothelial denudation injury was induced in the carotid arteries of Sam68-null (Sam68 -/- ) and WT mice. Sam68 -/- mice displayed an accelerated re-endothelialization ( P <0.05 at day 5 post-injury) and attenuated neointima formation (by 2.2 folds, P <0.05, at day 14), which was associated with a reduced number of macrophages and lowered expression of pro-inflammatory cytokines (i.e., TNF-alpha, MCP-1 and IL-6) in the injured vessels. In cultured Raw264.7 macrophages, knockdown of Sam68 resulted in a significant reduction in the TNF-α-induced expression of TNF-α, MCP-1, and IL-6 and in the level of nuclear phospho-p65, which indicates attenuated NF-kB activation. These results were confirmed in peritoneal macrophages and macrophages differentiated from bone-marrow mononuclear cells of Sam68 -/- and WT mice. To identify molecular mechanisms, Raw264.7 cells were treated with TNF-α and Vehicle, followed by Sam68 co-immunoprecipitation and mass-spectrometric identification of the Sam68-interacting proteins. We found that TNF-α treatment results in altered interactions of Sam68 with 22 cytosolic, cytoskeletal, and nuclear proteins. Further experiments are under way to validate their involvement in the NF-kB signaling. Conclusions: Our results for the first time suggest that Sam68 promotes pro-inflammatory response in injured arteries and impedes recovery, and this effect may be partially attributable to the exaggerated NF-kB activity.


2015 ◽  
Vol 117 (suppl_1) ◽  
Author(s):  
Shuling Han ◽  
Junlan Zhou ◽  
Baron T Arnone ◽  
Dauren Biyashev ◽  
Chan Boriboun ◽  
...  

Background: The role of Src-associated in mitosis 68 kDa (Sam68) in cardiovascular biology has not been studied. A recent report suggests that Sam68 suppresses TNF-α-induced NF-κB activation. Since NF-κB plays a critical role in vascular inflammation and injury via generation of inflammatory cytokines and recruitment of inflammatory cells, we sought to dissect the mechanism by which Sam68 regulates NF-κB signaling and its functional significance during vascular injury. Methods & Results: The endothelial denudation injury was induced in the carotid arteries of Sam68-/- and WT mice. Sam68-/- mice displayed an accelerated re-endothelialization and attenuated neointima hyperplasia, which was associated with a reduced number of macrophages and lowered expression of pro-inflammatory cytokines (i.e., TNF-α, IL-1β and IL-6) in the injured vessels. Importantly, the ameliorated vascular remodeling was recapitulated in WT mice after transplantation of bone marrow (BM) from Sam68-/- mice, suggesting beneficial role was attributed largely to BM-derived inflammatory cells. In cultured Raw264.7 macrophages, knockdown of Sam68 resulted in a significant reduction in the TNF-α-induced expression of TNF-α, IL-1β, and IL-6 and in the level of nuclear phospho-p65, indicating an attenuated NF-κB activation. These results were confirmed in peritoneal macrophages and macrophages differentiated from BM mononuclear cells of Sam68-/- and WT mice. To identify molecular mechanisms, Raw264.7 cells were treated with TNF-α and Vehicle, followed by Sam68 co-immunoprecipitation and mass-spec identification of Sam68-interacting proteins. Specifically, TNF-α treatment results in altered interactions of Sam68 with Filamin A (FLNA), a cytoskeleton protein known to be involved in NF-κB activation. Loss- and gain-of-function of Sam68 and FLNA suggest their mutual dependence in NF-κB activation and pro-inflammatory cytokine expression, and Sam68 is required for TRAF2-FLNA interaction. Conclusions: Our results for the first time suggest that Sam68 promotes pro-inflammatory response in injured arteries and impedes recovery, and this effect is attributed, in part, to the exaggerated NF-κB activity via Sam68-FLNA interaction and consequent TRAF2 stabilization.


Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 1276-1276
Author(s):  
Jianfei Qian ◽  
Jing Yang ◽  
Siqing Wang ◽  
Liang Zhang ◽  
Sungyoul Hong ◽  
...  

Abstract Human C-reactive protein (CRP) is an acute-phase protein, and elevated levels of CRP are present in patients with infections, inflammatory diseases, necrosis such as myocardial infarction, or malignancies including multiple myeloma (MM), lymphoma, and carcinoma. CRP has many biological functions and is involved in host defense, regulation of inflammation, and modulation of autoimmune diseases. Although our current understanding of CRP interaction with complement and Fcγ receptors (FcγR) has elucidated a regulatory role of CRP in these disease situations, it is not clear whether CRP affects the function of immune cells such as dendritic cells (DCs). In this study, we investigated the effect of CRP on DC differentiation, maturation, and function. CD14+ monocytes isolated from human peripheral blood mononuclear cells were cultured in RPMI-1640 medium supplemented with GM-CSF and IL-4 for 5 days to generate immature DCs (imDCs), and were further treated with IL-1β and TNF-α for 2 additional days to produce mature DCs (mDCs). CRP (5–100 μg/mL) was added to the cultures during DC differentiation (on days 0 and 3) or maturation (on day 5). The presence of CRP in cultures reduced imDC cell yields in a dose-dependent manner. Significantly lower cell yields were detected in cultures with 5 to 10 μg/mL CRP. Compared with untreated controls, CRP treatment (10 μg/mL) led to inhibited surface expression of DC-related molecules HLA-ABC, CD1a, CD40, and CD54; increased secretion of IL-6, IL-8, and IL-10; reduced production of TGF-β by imDCs; and decreased secretion of IL-12 by mDCs. Furthermore, the function of CRP-treated DCs was also impaired, evident by the markedly decreased ability of imDCs to phagocytose apoptotic cells and to uptake and present soluble antigen to antigen-specific T cells. Compared with untreated controls, CRP-treated mDCs had reduced capacity at activating allospecific T cells, which consequently secreted significantly lower amounts of IFN-γ, IL-2, and TNF-α compared with T cells activated by normal mDCs. Western blot analysis showed that CRP treatment led to inhibited phosphorylation of ERK and p38 MAPKs, and inhibited NFκB activity in the differentiating cells. Monocytes and DCs all express FcγRI (CD64), FcγRII (CD32), and FcγRIII (CD16), and the expression of FcγRII, but not FcγRI and FcγRIII, were upregulated on CRP-treated DCs. The detrimental effects of CRP on DCs were abrogated by blocking antibody against CRP and by antibody against FcγRII, but not against FcγRI or FcγRIII. These results indicate that CRP affected DC differentiation via binding to cell surface FcγRII. Taken together, this study demonstrates for the first time that CRP at high concentrations has detrimental effects on in vitro differentiation and function of DCs. Further studies will be needed to examine the clinical and biological relevance of this observation.


2005 ◽  
Vol 72 (2) ◽  
pp. 195-202 ◽  
Author(s):  
Celso G Vinderola ◽  
Jairo Duarte ◽  
Deepa Thangavel ◽  
Gabriela Perdigón ◽  
Edward Farnworth ◽  
...  

Kefir is a fermented milk produced by the action of lactic acid bacteria, yeasts and acetic acid bacteria, trapped in a complex matrix of polysaccharides and proteins. Beyond its inherent high nutritional value as a source of proteins and calcium, kefir has a long tradition of being regarded as good for health in countries where it is a staple in the diet. However, published human or animal feeding trials to substantiate this view are not numerous. The aim of this work was to determine the immunomodulating capacity of kefir on the intestinal mucosal immune response in mice and to demonstrate the importance of dose and cell viability on this response. BALB/c mice were fed with commercial kefir ad libitum (diluted 1/10, 1/50, 1/100 or 1/200) or pasteurized kefir (diluted 1/6, 1/10, 1/50, 1/100) for 2, 5 or 7 consecutive days. At the end of each feeding period, the bacterial translocation assay was performed in the liver. Small intestine structure was studied by haematoxilin-eosin staining and light microscopy. The number of IgA+ and IgG+ cells was also determined. For the functional doses chosen, cytokines (IL-2, IL-4, IL-6, IL-10, IL-12, TNF-α and IFN-γ) were determined. Kefir and pasteurized kefir were able to modulate the mucosal immune system in a dose-dependent manner. Kefir was administred 10-times more diluted than pasteurized kefir, but it induced an immunomodulation of similar magnitude, indicating the importance of cell viabilty. The results suggest that a Th1 response was controlled by Th2 cytokines induced by kefir feeding. Pasteurized kefir would induce both Th2 and Th1 responses. This is the first study in vivo regarding the mechanisms involved in the immunomodulating capacity of the oral administration of kefir containing viable or heat-inactivated bacteria at different doses.


2021 ◽  
Vol 8 ◽  
Author(s):  
Elodia Nataly Díaz-De la Cruz ◽  
José Ignacio Cerrillos-Gutiérrez ◽  
Andrés García-Sánchez ◽  
Carlos Gerardo Prado-Nevárez ◽  
Jorge Andrade-Sierra ◽  
...  

Patients with end-stage renal disease (ESRD) present alterations in mineral and bone metabolism. Hyperphosphatemia in ESRD is considered an independent risk factor for cardiovascular disease (CVD), increasing morbidity, and mortality. Sevelamer hydrochloride is a calcium-free, non-absorbable phosphate-chelating polymer. Calcium carbonate chelator is helpful in controlling serum phosphate levels. There is insufficient information on the influence of sevelamer hydrochloride and calcium carbonate on the behavior of oxidative stress (OS) markers and inflammation in patients on hemodialysis (HD). A randomized open clinical trial was carried out on patients to evaluate sevelamer hydrochloride and calcium carbonate influence at 6 months of study follow-up. Levels of oxidants (LPO, NO, and 8-isoprostanes), antioxidants (SOD and TAC), oxidative DNA damage (8-OHdG and hOGG1), pro-inflammatory cytokines (IL-6 and TNF-α), and inflammation markers (ferritin and C-reactive protein) were measured with colorimetric and ELISA methods. We found a significant increase in oxidants LPO and NO, and antioxidants SOD and TAC, and downregulation of IL-6 and TNF-α. Ferritin decrease at 6 months follow-up in the sevelamer hydrochloride group. Increase in C-reactive protein was found in the group of patients treated with calcium carbonate. In conclusion, we found an oxidative state imbalance with increase in LPO and NO oxidants. The activity of the antioxidant enzymes (SOD and TAC) was also found to increase, suggesting a compensatory effect in the face of increase in oxidants. The same phenomenon was observed with increase in the oxidative damage marker to DNA and the increase in the DNA repair enzyme, suggesting a compensatory effect. Pro-inflammatory cytokines were predominantly downregulated by TNF-α in the group that ingested sevelamer hydrochloride in the final determination at 6 months of follow-up. Serum ferritin levels decreased significantly at the end of follow-up in patients on HD in the sevelamer hydrochloride group. The management of hyperphosphatemia with sevelamer hydrochloride appears to have obvious anti-inflammatory and antioxidant benefits.


2013 ◽  
Vol 4 (1) ◽  
pp. 20-23
Author(s):  
A. N Zakirova ◽  
N. E Zakirova

Objective: to evaluate the severity of immuno-inflammatory responses under stable stenocardia in patients with ischemic heart disease (IHD). Patients and intervention: the study included 83 patients suffering from IHD. Among them 30 cases were diagnosed as functional class (FC)-II stenocardia, 27 cases as FC-III stenocardia and 26 cases as FC-IV stenocardia. The control group included 25 healthy persons. For characterizing the immuno-inflammatory responses we examined the level of C-reactive protein (CRP), pro-inflammatory (IL-1b, IL-6, TNF-α) and anti-inflammatory (IL-4, IL-10) cytokines by the immunoenzymic procedure. Results: FC-II stenocardia showed normal levels of CRP and pro-inflammatory cytokines. FC-III stenocardia was associated with a moderate increase in markers of an inflammation. FC-IV stenocardia was characterized by maximum levels of CRP and pro-inflammatory cytokines. Conclusion. The intensity of immuno-inflammatory responses depends on more or less serious course of stenocardia in patients with IHD.


2011 ◽  
Vol 58 (4) ◽  
Author(s):  
Irena Tam ◽  
Krystyna Stępień

A large body of evidence suggests that epidermal melanocytes are an integral part of the skin immune system and can be considered immunocompetent cells. Recently, it has been reported that human melanocytes constitutively express Toll-like receptors and may be involved in the induction of several inflammatory cytokines. In the study the secretion of IL-1β, IL-6 and TNF-α by cultured normal melanocytes was investigated after stimulation with lipopolysaccharide. LPS increased the secretion of IL-1β in a dose-dependent manner. IL-1β stimulated release of IL-6 and TNF-α by melanocytes, whereas LPS activated production of TNF-α, but not of IL-6. These observations indicate that LPS can participate in the regulation of cytokine activity in normal human melanocytes and suggest that cytokines released by melanocytes could affect melanocytes themselves or/and other cells of the epidermis.


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