Kallikrein-kininogen system activation and bradykinin (B2) receptors in indomethacin induced enterocolitis in genetically susceptible Lewis rats

Background—The plasma kallikrein-kinin (K-K) system is activated in acute and chronic relapsing intestinal inflammation induced in Lewis rats by intramural injection of exogenous bacterial components. Aims—To determine whether this effect is model specific, K-K system activation was investigated in a modified indomethacin induced enterocolitis model, as well as bradykinin 2 (B2) receptor distribution in the normal and acutely inflamed intestine. Methods—Lewis rats injected with daily sublethal doses of indomethacin for two days developed acute (two days) and chronic (14 days) intestinal inflammation. Plasma prekallikrein (amidolytic), high molecular weight kininogen (HK, coagulant) and cleavage of HK (western blot) were assayed to detect K-K activation. Results—Liver and spleen weights were significantly higher, and body weights and haematocrit values were significantly lower in the indomethacin group than in the control group. During both acute and chronic phases, rats displayed K-K system activation manifested by a significant decrease in plasma prekallikrein and HK functional levels, and by HK cleavage. Plasma T kininogen (a major acute phase protein) was significantly elevated. B2 receptors were identified in both normal and inflammatory intestine with more prominent specific immunohistochemical staining in the acutely inflamed tissue. Conclusions—K-K system activation occurs in association with both acute and chronic phases of intestinal injury, regardless of the triggering agent, suggesting that activation of this system is integrally involved in intestinal inflammation in genetically susceptible hosts. Localisation of B2 receptors across intestinal layers provides a structural basis for the kinin function in the intestine

A monoclonal antibody against kininogen reduces inflammation in the HLA-B27 transgenic rat

The human leukocyte antigen B27 (HLA-B27) transgenic rat is a model of human inflammatory bowel disease, rheumatoid arthritis and psoriasis. Studies of chronic inflammation in other rat models have demonstrated activation of the kallikrein–kinin system as well as modulation by a plasma kallikrein inhibitor initiated before the onset of clinicopathologic changes or a deficiency in high-molecular-mass kininogen. Here we study the effects of monoclonal antibody C11C1, an antibody against high-molecular-mass kininogen that inhibits the binding of high-molecular-mass kininogen to leukocytes and endothelial cells in the HLA-B27 rat, which was administered after the onset of the inflammatory changes. Thrice-weekly intraperitoneal injections of monoclonal antibody C11C1 or isotype IgG(1 )were given to male 23-week-old rats for 16 days. Stool character as a measure of intestinal inflammation, and the rear limbs for clinical signs of arthritis (tarsal joint swelling and erythema) were scored daily. The animals were killed and the histology sections were assigned a numerical score for colonic inflammation, synovitis, and cartilage damage. Administration of monoclonal C11C1 rapidly decreased the clinical scores of pre-existing inflammatory bowel disease (P < 0.005) and arthritis (P < 0.001). Histological analyses confirmed significant reductions in colonic lesions (P = 0.004) and synovitis (P = 0.009). Decreased concentrations of plasma prekallikrein and high-molecular-mass kininogen were found, providing evidence of activation of the kallikrein–kinin system. The levels of these biomarkers were reversed by monoclonal antibody C11C1, which may have therapeutic potential in human inflammatory bowel disease and arthritis

Selective kallikrein-kinin system activation in inbred rats differentially susceptible to granulomatous enterocolitis

AbstractBACKGROUND & AIMS: Crohn's disease is characterized by unrestrained inflammation with a genetic component. Genetic susceptibility and activation of the kalli-krein-kinin (contact) system were investigated in experimental enterocolitis and extraintestinal inflammation induced by bacterial polymers. METHODS: Kinetics of inflammation in inbred Lewis and Buffalo rats injected subserosally with peptidoglycan- polysaccharide polymers were correlated with in vivo and in vitro activation of the contact system. RESULTS: Lewis rats had a biphasic course of enterocolitis. Acute inflammation peaked 1 day after injection, gradually decreasing until day 14 when intestinal inflammation spontaneously reactivated and persisted for 16 weeks, accompanied by arthritis, granulomatous hepatitis, anemia, and leukocytosis. Self-limited acute enterocolitis in Buffalo rats resolved by 24 days without extraintestinal involvement. Consumption of the precursor proteins prekalli-krein and high-molecular-weight kininogen indicated activation of the plasma contact system in Lewis rats and closely correlated with chronic intestinal inflammation. Contact system activation did not occur in Buffalo rats, even during acute inflammation. In vitro studies showed a decreased rate of kininogen cleavage in Buffalo plasma. CONCLUSIONS: Selective in vivo and in vitro activation of the contact system in susceptible Lewis rats suggests that this pathway is one determinant of genetic susceptibility to granulomatous enterocolitis and systemic complications. (Gastroenterology 1996 May;110(5):1467-81

Inflammatory bowel disease: past, present, and future

Crohn’s disease and ulcerative colitis, collectively known as the inflammatory bowel diseases (IBD), are largely diseases of the twentieth century, and are associated with the rise of modern, Westernized industrial society. Although the causes of these diseases remain incompletely understood, the prevailing model is that the intestinal flora drives an unmitigated intestinal immune response and inflammation in the genetically susceptible host. A review of the past and present of these diseases shows that detailed description preceded more fundamental elucidation of the disease processes. Working out the details of disease pathogenesis, in turn, has yielded dividends in more focused and effective therapy for IBD. This article highlights the key descriptions of the past, and the pivotal findings of current studies in disease pathogenesis and its connection to medical therapy. Future directions in the IBD will likely explicate the inhomogeneous causes of these diseases, with implications for individualized therapy

Protective effects of N-acetylcysteine on acetic acid-induced colitis in a porcine model

BACKGROUND: Ulcerative colitis is a chronic inflammatory disease and involves multiple etiological factors. Acetic acid (AA)-induced colitis is a reproducible and simple model, sharing many characteristics with human colitis. N-acetylcysteine (NAC) has been widely used as an antioxidant in vivo and in vitro. NAC can affect several signaling pathways involving in apoptosis, angiogenesis, cell growth and arrest, redox-regulated gene expression, and inflammatory response. Therefore, NAC may not only protect against the direct injurious effects of oxidants, but also beneficially alter inflammatory events in colitis. This study was conducted to investigate whether NAC could alleviate the AA-induced colitis in a porcine model. METHODS: Weaned piglets were used to investigate the effects of NAC on AA-induced colitis. Severity of colitis was evaluated by colon histomorphology measurements, histopathology scores, tissue myeloperoxidase activity, as well as concentrations of malondialdehyde and pro-inflammatory mediators in the plasma and colon. The protective role of NAC was assessed by measurements of antioxidant status, growth modulator, cell apoptosis, and tight junction proteins. Abundances of caspase-3 and claudin-1 proteins in colonic mucosae were determined by the Western blot method. Epidermal growth factor receptor, amphiregulin, tumor necrosis factor-alpha (TNF-α), and toll-like receptor 4 (TLR4) mRNA levels in colonic mucosae were quantified using the real-time fluorescent quantitative PCR. RESULTS: Compared with the control group, AA treatment increased (P < 0.05) the histopathology scores, intraepithelial lymphocyte (IEL) numbers and density in the colon, myeloperoxidase activity, the concentrations of malondialdehyde and pro-inflammatory mediators in the plasma and colon, while reducing (P < 0.05) goblet cell numbers and the protein/DNA ratio in the colonic mucosa. These adverse effects of AA were partially ameliorated (P < 0.05) by dietary supplementation with NAC. In addition, NAC prevented the AA-induced increase in caspase-3 protein, while stimulating claudin-1 protein expression in the colonic mucosa. Moreover, NAC enhanced mRNA levels for epidermal growth factor and amphiregulin in the colonic mucosa. CONCLUSION: Dietary supplementation with NAC can alleviate AA-induced colitis in a porcine model through regulating anti-oxidative responses, cell apoptosis, and EGF gene expression

Cutaneous manifestations in patients with inflammatory bowel diseases: pathophysiology, clinical features, and therapy.

The skin is one of the most common extraintestinal organ system affected in patients with inflammatory bowel disease (IBD), including both Crohn's disease and ulcerative colitis. The skin manifestations associated with IBD are polymorphic and can be classified into 4 categories according to their pathophysiology: (1) specific, (2) reactive, (3) associated, and (4) induced by IBD treatment. Cutaneous manifestations are regarded as specific if they share with IBD the same granulomatous histopathological pattern: perianal or metastatic Crohn's disease (commonly presenting with abscesses, fistulas or hidradenitis suppurativa-like features) is the prototype of this setting. Reactive cutaneous manifestations are different from IBD in the histopathology but have close physiopathological links: pyoderma gangrenosum, a neutrophil-mediated autoinflammatory skin disease typically manifesting as painful ulcers, is the paradigm of this group. Among the cutaneous diseases associated with IBD, the most commonly seen are erythema nodosum, a form of panniculitis most commonly involving bilateral pretibial areas, and psoriasis, a T helper 1/T helper 17-mediated erythematous squamous inflammatory disease. Finally, the number of cutaneous adverse reactions because of IBD therapies is progressively increasing. The most frequent drug-induced cutaneous manifestations are psoriasis-like, eczema-like, and lichenoid eruptions, as well as cutaneous lupus erythematosus for biologics, and nonmelanoma skin cancer, mainly basal cell and squamous cell carcinomas for thiopurines

Locus nascendi factors for the economic goods allocation

The paper presents the economic goods allocation depending on their production factors. The feasibility study is made for the existence of four groups and several subgroups of economic goods, dominated by one “Siamese”pair. The classifi cation of economic goods depending on their place of production factors is made, that will help to improve the quality and effi ciency of decision making on the choice of the optimal production placement

Cutaneous manifestations in patients with inflammatory bowel diseases: Pathophysiology, clinical features, and therapy

The skin is one of the most common extraintestinal organ system affected in patients with inflammatory bowel disease (IBD), including both Crohn's disease and ulcerative colitis. The skin manifestations associated with IBD are polymorphic and can be classified into 4 categories according to their pathophysiology: (1) specific, (2) reactive, (3) associated, and (4) induced by IBD treatment. Cutaneous manifestations are regarded as specific if they share with IBD the same granulomatous histopathological pattern: perianal or metastatic Crohn's disease (commonly presenting with abscesses, fistulas or hidradenitis suppurativa-like features) is the prototype of this setting. Reactive cutaneous manifestations are different from IBD in the histopathology but have close physiopathological links: pyoderma gangrenosum, a neutrophil-mediated autoinflammatory skin disease typically manifesting as painful ulcers, is the paradigm of this group. Among the cutaneous diseases associated with IBD, the most commonly seen are erythema nodosum, a form of panniculitis most commonly involving bilateral pretibial areas, and psoriasis, a T helper 1/T helper 17-mediated erythematous squamous inflammatory disease. Finally, the number of cutaneous adverse reactions because of IBD therapies is progressively increasing. The most frequent drug-induced cutaneous manifestations are psoriasis-like, eczema-like, and lichenoid eruptions, as well as cutaneous lupus erythematosus for biologics, and nonmelanoma skin cancer, mainly basal cell and squamous cell carcinomas for thiopurines. Copyright \ua9 2013 Crohn's & Colitis Foundation of America, Inc