Partial purification of the anti-inflammatory factor(s) in inflammatory exudate

Research on drug treatment and the novel signaling pathway of chronic atrophic gastritis

BACKGROUND

Chronic atrophic gastritis (CAG) is a global digestive system disease and one of the important causes of gastric cancer. The incidence of CAG has been increasing yearly worldwide.

PURPOSE

This article reviews the latest research on the common causes and future therapeutic targets of CAG as well as the pharmacological effects of corresponding clinical drugs. We provide a detailed theoretical basis for further research on possible methods for the treatment of CAG and reversal of the CAG process.

RESULTS

CAG often develops from chronic gastritis, and its main pathological manifestation is atrophy of the gastric mucosa, which can develop into gastric cancer. The drug treatment of CAG can be divided into agents that regulate gastric acid secretion, eradicate Helicobacter. pylori (H. pylori), protect gastric mucous membrane, or inhibit inflammatory factors according to their mechanism of action. Although there are limited specific drugs for the treatment of CAG, progress is being made in defining the pathogenesis and therapeutic targets of the disease. Growing evidence shows that NF-κB, PI3K/AKT, Wnt/ β-catenin, MAPK, Toll-like receptors (TLRs), Hedgehog, and VEGF signaling pathways play an important role in the development of CAG.

Regulation of macrophage activation and inflammation by spermine: a new chapter in an old story

Spermine, a naturally occurring polyamine, is a ubiquitous structural component of all eukaryotic cells. Regenerating tissues produce higher levels of spermine, and injured or dying cells release spermine into the extracellular milieu, so that tissue levels increase significantly at inflammatory sites of infection or injury. Recent research has focused on delineating the significance of spermine accumulation in the inflammatory process. The discovery that spermine is a negative regulator of macrophage activation provided a mechanism by which spermine influences the biology of inflammation. Mechanistic studies indicate that spermine is incorporated into macrophages and restrains the innate immune response. This anti-inflammatory process is facilitated by the negative acute-phase protein, fetuin.

Inhibition of the respiratory burst of human neutrophils by the polyamine oxidase-polyamine system

The addition of the polyamines, spermine and spermidine, to human neutrophils caused a depression of the hexose-monophosphate (HMP) shunt activity of neutrophils stimulated with latex particles but not of unstimulated cells. The effect was dependent on the presence of bovine serum and was not observed when normal human serum was substituted for bovine serum. The polyamine oxidase (PAO) in bovine serum was probably responsible for generating the activity since normal human serum lacks PAO. A role for PAO was further supported by the finding that partially purified bovine PAO in the presence of polyamines similarly mediated inhibition of HMP shunt activity in stimulated neutrophils. Catalase failed to prevent the inhibitory effects of the PAO-polyamine system suggesting that H2O2 is not the responsible product. In addition, our results show that human pregnancy serum known to contain PAO activity in the presence of polyamines mediated a similar inhibition of the respiratory burst.

Inhibition of human neutrophil locomotion by the polyamine oxidase-polyamine system

The polyamines, spermine and spermidine, in the presence of either bovine serum [containing polyamine oxidase (PAO) activity] or partially purified PAO, inhibited human neutrophil locomotion. This effect could not be produced by either bovine serum, PAO, or the polyamines alone. The results suggested that at least two of the products generated during the oxidation of polyamines by PAO, namely H2O2 and ammonia, are not responsible for the effects on neutrophils. Acrolein, a breakdown product of other products (aminoaldehydes), was found to inhibit the neutrophil functions. Since polyamines, and possibly PAOs, accumulate at inflammatory sites, products of the PAO-polyamine reaction could function as regulators of the inflammatory response.

Anti-inflammatory factors in sponge-induced exudate in the rat

Sterile polyester sponge-induced exudates in the rat have been investigated for high molecular weight substances with anti-inflammatory activity against carrageenan-induced oedema in the rat. The only substances found with this activity were dialysable molecules. Crude but sterile protein fractions isolated from exudate stabilized guinea-pig macrophages at low concentrations. The proteins present in exudates appeared to be identical to normal rat plasma proteins. It is concluded that anti-inflammatory activity associated with high molecular substances in exudate may have been due to bacterial contamination.

Putrescine--a potent endogenous anti-inflammatory substance in inflammatory exudates

Sponge-induced exudate from the rat and saline extracts of normal rat liver and rat liver damaged in situ by dimethylnitrosamine have been assayed for putrescine, spermidine and spermine levels. The three physiological oligoamines have been examined for anti-inflammatory activity by the carrageenan-induced oedema rat model and spermidine and putrescine were found to be anti-inflammatory with putrescine being about ten times as active as spermidine. Putrescine was also anti-inflammatory in the adjuvant arthritic rat model. Thioacetamide and theophylline were also anti-inflammatory and theophylline doubled the level of putrescine in rat liver. It was concluded that putrescine was a potent anti-inflammatory factor in the inflammatory exudates and extracts examined.

Inflammation, counter irritation and rat serum acute phase alpha 2-macroglobulin levels

Following the injection of turpentine and carrageenan into rats, laboratory models for counter irritation were assessed by measuring changes in paw thicknesses and serum acute phase alpha 2-macroglobulin concentrations. Both indices of inflammation were also examined in groups of rats dosed with 6-mercaptopurine, the best inhibitor found so far of elevated levels of alpha 2-macroglobulin in rat serum. Results showed that there is no relationship between the degree of irritant-induced inhibition of inflammation and the serum concentration of the acute phase protein. Hence, at least in the models for counter irritation used in this study, alpha 2-macroglobulin cannot be viewed as an endogenous anti-inflammatory protein.

Modifications in the regression of the acute inflammation caused by a beta-adrenergic effect unbalanced by the alpha-component ("biased beta-effect")

A biased beta-adrenergic effect was produced either by blocking the alpha-adrenergic component of endogenous catecholamines using phentolamine or by application of isoproterenol. Both experimental conditions led to a prolongation of the lymphocyte phase of the inflammatory process. A beta-bias also curbed the activity of a substance (or substances) inhibiting the ingress of lymphocytes into the site of inflammation (subcutaneously injected Sephadex) around the fourth and fifth day after the onset of inflammation. This lack in activity is evidently connected with the prolonged lymphocyte phase.

Purification and characterization of an anti-inflammatory factor (AIF) from bovine serum

An anti-inflammatory factor (AIF) was highly purified from normal bovine serum. The purified AIF was a polysaccharide which was formed from a low molecular substance Pro-AIF by macromolecularization. AIF showed potent inhibitory activities against carrageenin induced edema in rats and PMN-leucocyte chemotaxis. It showed no inhibition in cutaneous reaction with serotonin, bradykinin or a mediator releaser compound 48/80. No inhibition was also observed in thermally induced pain, reversed passive Arthus reaction and adjuvant polyarthritis in rats. With these results, the role of AIF in inflammation was discussed.

Some biological and pharmacological properties of inflammatory exudates

Inflammatory exudates were obtained from polyester sponges which had been implanted subcutaneously in rats four days previously. This material was found to be anti-inflammatory when injected into other rats in which carrageenan pleurisy had been induced. At a dose of 600 mg kg-1 exudate inhibited the formation of pleural effusion, emigration of both neutrophils and mononuclear cells and the accumulation of beta-glucuronidase and lactic dehydrogenase. The same dose of sponge exudate did not however inhibit the increased vascular permeability induced in the rat skin or rat foot following injection of 5-hydroxytryptamine, histamine, prostaglandin E1, or bradykinin. Furthermore sponge exudate did not reduce the haemolytic complement titre of rat serum either in vivo or in vitro. The possible mechanism of anti-inflammatory action of exudate is discussed.

The possible occurrence of endogenous anti-inflammatory substances in the blood of injured rats

1 Using the carrageenin rat paw oedema test as an assay, an attempt has been made to confirm the presence of anti-inflammatory activity in the blood of rats with a chronic inflammatory lesion induced by a polyester sponge, and to relate such activity to the systemic anti-inflammatory effect exerted in situ by the lesion. In addition, plasma from rats given acetic acid intraperitoneally has been examined for anti-inflammatory properties. 2 The activity of serum obtained from sponge-bearing adrenalectomized Wistar rats did not differ significantly from that obtained from animals without implants. Furthermore, implanted sponges exerted no systemic anti-inflammatory effect. 3 Similar experiments were performed in sponge-bearing adrenalectomized Sprague-Dawley rats, plasma instead of serum being examined for anti-inflammatory activity. The plasma removed from such animals possessed no anti-inflammatory activity, whilst implanted sponges exerted a small, yet significant, systemic inhibitory effect. 4 When the irritancy of sponge implants was augmented with croton oil, more marked systemic anti-inflammatory effects were observed. However, the plasma obtained from rats injured in this manner exerted no anti-inflammatory effect. 5 No anti-inflammatory activity could be detected in plasma samples obtained from rats treated with doses of acetic acid capable of producing pronounced systemic anti-inflammatory effects. 6 It was concluded that the induction of these inflammatory lesions in rats does not appear to lead to a detectable release of endogenous anti-inflammatory substances into the circulation.

Anti-inflammatory and irritant effects of a fraction from normal human plasma

1 By the use of carrageenan-induced rat paw oedema assay the anti-inflammatory activity of a fraction isolated from normal human plasma has been measured after its intravenous, intraperitoneal and oral administration. Its effects in the dextran-induced rat paw oedema and the systemic dextran anaphylactoid reaction in the rat were also studied.2 The fraction showed marked anti-inflammatory activity in the carrageenan test after intravenous administration and a smaller but still significant activity when given intraperitoneally, but was inactive orally after the administration of a larger dose. It was active in the dextran-induced paw oedema test but not against the anaphylactoid reaction.3 A comparison between its anti-inflammatory and irritant properties revealed no correlation when each parameter was determined in relation to dose. The fraction did not affect the blood pressure of the anaesthetized rat.4 These findings are discussed in relation to the existence of a natural anti-inflammatory substance or substances in human plasma.

Separation of irritancy from the anti-inflammatory component of inflammation exudate

The anti-inflammatory component found in inflammation exudates has been purified by Sephadex gel filtration and preparative polyacrylamide electrophoresis. Highly purified material produces no greater irritancy upon injection than 0.9% sodium chloride.

Effect of a dorsal dermal surgical wound on the chemical response of rat abdominal skin to chronic administration of sodium diphenylhydantoin

A dorsal dermal surgical wound inflicted five days before excision of abdominal skin from young rats that were under treatment with daily injections of sodium diphenylhydantoin (100 or 50 mg/ kg) greatly modified the dermal chemical response to this drug that was observed in unwounded animals. Sodium diphenylhydantoin failed to increase wound rupture strength.

Relationship between the anti-inflammatory and irritant properties of inflammatory exudate

1. Using the rat paw oedema assay procedure a comparison was made between the anti-inflammatory and irritant properties of the inflammatory exudate obtained from polyester sponges implanted subcutaneously in adrenalectomized rats. Where necessary, comparison was also made with a known counter-irritant, carrageenin.2. A significant correlation between the anti-inflammatory and irritant properties of sponge exudate was observed when each parameter was determined in relation to dose. A similar result was obtained with carrageenin.3. A comparison of the two activities of sponge exudate samples harvested at various times following sponge implantation did not give a significant correlation although in each case significant anti-inflammatory activity was accompanied by marked irritation.4. Time-effect curves of the two activities of sponge exudate showed a significant correlation over the time period examined. However, no such correlation was obtained using carrageenin.5. Both activities of sponge exudate were retained following dialysis.6. These findings are discussed in relation to a counter-irritant mode of action for sponge exudate.