Histamine release induced by dendroaspis natriuretic peptide from rat mast cells

Pain and Cellular Migration Induced by Bothrops jararaca Venom in Mice Selected for an Acute Inflammatory Response: Involvement of Mast Cells

Bothrops jararaca venom (BjV) can induce mast cell degranulation. In order to investigate the role of mast cells and the interference of the host genetic background in the inflammation induced by BjV, we have used mouse strains selected for maximal (AIRmax) or minimal (AIRmin) acute inflammatory response (AIR). Mice were pretreated with an inhibitor of mast cell degranulation, cromolyn (CROM), and injected in footpads or intraperitoneally (i.p.) with BjV. Pain was measured with von Frey hairs, cell migration in the peritoneum by flow cytometry, and reactive oxygen species (ROS) production by chemiluminescence assays. The nociceptive response to BjV was higher in AIRmax than AIRmin mice; however, this difference was abolished by pretreatment with CROM. BjV induced peritoneal neutrophil (CD11b+ GR-1+) infiltration and ROS secretion in AIRmax mice only, which were partially inhibited by CROM. Our findings evidence a role for mast cells in pain, neutrophil migration, and ROS production triggered by BjV in AIRmax mice that are more susceptible to the action of BjV.

Organic and Peptidyl Constituents of Snake Venoms: The Picture Is Vastly More Complex Than We Imagined

Small metabolites and peptides in 17 snake venoms (Elapidae, Viperinae, and Crotalinae), were quantified using liquid chromatography-mass spectrometry. Each venom contains >900 metabolites and peptides. Many small organic compounds are present at levels that are probably significant in prey envenomation, given that their known pharmacologies are consistent with snake envenomation strategies. Metabolites included purine nucleosides and their bases, neurotransmitters, neuromodulators, guanidino compounds, carboxylic acids, amines, mono- and disaccharides, and amino acids. Peptides of 2⁻15 amino acids are also present in significant quantities, particularly in crotaline and viperine venoms. Some constituents are specific to individual taxa, while others are broadly distributed. Some of the latter appear to support high anabolic activity in the gland, rather than having toxic functions. Overall, the most abundant organic metabolite was citric acid, owing to its predominance in viperine and crotaline venoms, where it chelates divalent cations to prevent venom degradation by venom metalloproteases and damage to glandular tissue by phospholipases. However, in terms of their concentrations in individual venoms, adenosine, adenine, were most abundant, owing to their high titers in Dendroaspis polylepis venom, although hypoxanthine, guanosine, inosine, and guanine all numbered among the 50 most abundant organic constituents. A purine not previously reported in venoms, ethyl adenosine carboxylate, was discovered in D. polylepis venom, where it probably contributes to the profound hypotension caused by this venom. Acetylcholine was present in significant quantities only in this highly excitotoxic venom, while 4-guanidinobutyric acid and 5-guanidino-2-oxopentanoic acid were present in all venoms.

[6]-Shogaol inhibits the production of proinflammatory cytokines via regulation of NF-κB and phosphorylation of JNK in HMC-1 cells

[6]-Shogaol is a major bioactive component of Zingiber officinale. Although [6]-shogaol has a number of pharmacological activities including antipyretic, analgesic, antitussive and anti-inflammatory effects, the specific mechanisms of its anti-allergic effects have not been studied. In this study, we present the effects of [6]-shogaol on mast cell-mediated allergic reactions in vivo and in vitro. Sprague-Dawley rats received intradermal injections of anti-DNP IgE was injected into dorsal skin sites. After 48 h, [6]-shogaol was administered orally 1 h prior to challenge with DNP-HSA in saline containing 4% Evans blue through the dorsal vein of the penis. In addition, rat peritoneal mast cells (RPMCs) were cultured and purified to investigate histamine release. In vitro, we evaluated the regulatory effects of [6]-shogaol on the level of inflammatory mediators in phorbol 12-myristate 13-acetate plus calcium ionomycin A23187-stimulated human mast cells (HMC-1). [6]-Shogaol reduced the passive cutaneous anaphylaxis reaction compared to the control group, and histamine release decreased significantly following the treatment of RPMCs with [6]-shogaol. In HMC-1 cells, [6]-shogaol inhibited the production of TNF-α, IL-6 and IL-8, as well as the activation of nuclear factor-κB (NF-κB) and phosphorylation of JNK in compound 48/80-induced HMC-1 cells. [6]-shogaol inhibited mast cell-mediated allergic reactions by inhibiting the release of histamine and the production of proinflammatory cytokines with the involvement of regulation of NF-κB and phosphorylation of JNK.

The role of mast cells in atrial natriuretic peptide-induced cutaneous inflammation

Atrial natriuretic peptide (ANP) is widely distributed throughout the heart, skin, gastrointestinal and genital tracts, and nervous and immune systems. ANP acts to mediate vasodilation and induces mast cell activation in both human and rats in vitro. However, the mechanisms of ANP-induced mast cell activation, the extent to which ANP can induce tissue swelling, mast cell degranulation, and granulocyte infiltration in mouse skin are not fully understood. This issue was investigated by treatment with ANP in rat peritoneal mast cells (RPMCs) and mouse peritoneal mast cells (MPMCs) in vitro and by injection of ANP into the skin of congenic normal WBB6F1/J-Kit+/Kit+ +/+, genetically mast cell-deficient WBB6F1/J-Kit(W)/Kit(W-v) (W/W(v)) and mast cell-engrafted W/W(v) (BMCMC→W/W(v)) mice in vivo. ANP induced the release of histamine and TNF-α from RPMCs and enhanced serotonin release from MPMCs, in a dose-dependent fashion, as well as reduced cAMP level of RPMCs in vitro. In +/+ mice, ANP induced significant tissue swelling, mast cell degranulation, and granulocyte infiltration in a dose-dependent manner, whereas not in genetically mast cell-deficient W/W(v) mice. However, ANP-induced cutaneous inflammation has been restored in BMCMC→W/W(v) mice. These data indicate that mast cells play a key role in the ANP-induced cutaneous inflammation.

Pathological axes of wound repair: gastrulation revisited

Post-traumatic inflammation is formed by molecular and cellular complex mechanisms whose final goal seems to be injured tissue regeneration.

In the skin -an exterior organ of the body- mechanical or thermal injury induces the expression of different inflammatory phenotypes that resemble similar phenotypes expressed during embryo development. Particularly, molecular and cellular mechanisms involved in gastrulation return. This is a developmental phase that delineates the three embryonic germ layers: ectoderm, endoderm and mesoderm. Consequently, in the post-natal wounded skin, primitive functions related with the embryonic mesoderm, i.e. amniotic and yolk sac-derived, are expressed. Neurogenesis and hematogenesis stand out among the primitive function mechanisms involved.

Interestingly, in these phases of the inflammatory response, whose molecular and cellular mechanisms are considered as traces of the early phases of the embryonic development, the mast cell, a cell that is supposedly inflammatory, plays a key role.

The correlation that can be established between the embryonic and the inflammatory events suggests that the results obtained from the research regarding both great fields of knowledge must be interchangeable to obtain the maximum advantage.

Inhibition of anaphylaxis-like reaction and mast cell activation by water extract from the fruiting body of Phellinus linteus

Mast cell-mediated anaphylactic reaction is involved in many allergic diseases such as asthma and allergic rhinitis. Phellinus linteus has been used as a traditional herb medicine in oriental countries and is known to have anti-tumor, immunomodulatory, anti-inflammatory, and anti-allergic activities. However, roles of Phellinus linteus in the mast cell-mediated anaphylactic reactions have not fully been examined. In the present study, we have investigated the effects of water extract from the fruiting body of Phellinus linteus (WEPL) on mast cell-mediated anaphylaxis-like reactions. Oral administration of WEPL inhibited the compound 48/80-induced systemic anaphylaxis-like reaction and ear swelling response. WEPL also inhibited the anti-dinitrophenyl (DNP) IgE-mediated passive systemic and cutaneous anaphylaxis. WEPL had no cytotoxicity on rat peritoneal mast cells (RPMC). WEPL dose-dependently reduced histamine release from RPMC activated by compound 48/80 or anti-DNP IgE. Moreover, WEPL decreased the compound 48/80-induced calcium uptake into RPMC. Furthermore, WEPL increased the level of intracellular cAMP and significantly inhibited the compound 48/80-induced cAMP reduction in RPMC. These results suggest that WEPL may serve as an effective therapeutic agent for allergic diseases.

Inhibitory effects of Morus alba on compound 48/80-induced anaphylactic reactions and anti-chicken gamma globulin IgE- mediated mast cell activation

We investigated the effects of hot-water extract from the root bark of Morus alba (HEMA) on anaphylactic reactions. Using in vitro and in vivo experiments, we examined whether HEMA could inhibit compound 48/80-induced systemic anaphylactic shock and anti-chicken gamma globulin (CGG) IgE-mediated rat peritoneal mast cell activation. HEMA significantly inhibited systemic anaphylaxis induced by the compound 48/80 in mice. HEMA also significantly inhibited the passive cutaneous anaphylaxis activated by anti-CGG IgE. HEMA had no cytotoxicity on rat peritoneal mast cells (RPMC). Moreover, HEMA dose-dependently inhibited mast cell degranulation, histamine release and calcium uptake into RPMC induced by the compound 48/80 or anti-CGG IgE. When HEMA was added, the level of intracellular cAMP in RPMC showed a transient and significant increase (5-fold) compared with that of control cells. HEMA also inhibited significantly the compound 48/80-induced cAMP reduction in RPMC. These results suggested that HEMA inhibits the compound 48/80- or anti-CGG IgE-induced mast cell activation and its inhibitory effects on mast cell activations were favorably comparable to disodium cromoglycate. And HEMA is a candidate for effective therapeutic tools of allergic diseases.

Inhibitory effects of Houttuynia cordata water extracts on anaphylactic reaction and mast cell activation

The present study was investigated the effect of Houttuynia cordata THUNB water extract (HCWE) on mast cell-mediated anaphylactic reactions. The mast cell-mediated anaphylactic reaction is involved in many allergic diseases such as asthma and allergic rhinitis. HCWE has been used as a traditional medicine in Korea and is known to have an antioxidant and anti-cancer activities. However, its specific effect of mast cell-mediated anaphylactic reactions is still unknown. We examined whether HCWE could inhibit compound 48/80-induced systemic anaphylaxis, IgE-mediated passive cutaneous anaphylaxis (PCA), and mast cell activation. The oral administration of HCWE inhibited compound 48/80-induced systemic anaphylaxis in mice. HCWE also inhibited the local allergic reaction, PCA, activated by anti-dinitrophenyl (DNP) IgE antibody in rats. HCWE reduced the compound 48/80-induced mast cell degranulation and colchicine-induced deformation of rat peritoneal mast cells (RPMC). Moreover, HCWE dose-dependently inhibited histamine release and calcium uptake of RPMC induced by compound 48/80 or anti-DNP IgE. HCWE increased the level of intracellular cAMP and inhibited significantly the compound 48/80-induced cAMP reduction in RPMC. These results suggest that HCWE may be beneficial in the treatment of mast cell-mediated anaphylactic responses.

Inhibitory Effects of Agaricus blazei on Mast Cell-Mediated Anaphylaxis-Like Reactions

Agaricus blazei is a medicinal mushroom native to Brazil. It used to be a source of anti-tumor and immunmoactive compounds and considered a health food in many countries. However, its specific effect against mast cell-mediated anaphylactic reactions is still unknown. In the present study, we investigated the effect of Agaricus blazei water extract (ABWE) on mast cell-mediated anaphylaxis-like reactions. We examined whether ABWE could inhibit systemic anaphylaxis-like reaction, ear swelling response, passive cutaneous anaphylaxis, and mast cell activation. ABWE inhibited compound 48/80-induced systemic anaphylaxis-like reaction, ear swelling response, and passive cutaneous anaphylaxis-like reaction in mice. ABWE also inhibited anti-dinitrophenyl (DNP) IgE-mediated passive cutaneous anaphylaxis. ABWE dose-dependently inhibited compound 48/80-induced or anti-DNP IgE-mediated histamine release from rat peritoneal mast cells (RPMC). Moreover, pretreatment with ABWE reduced compound 48/80-induced calcium uptake into RPMC. When ABWE was added, the level of intracellular cAMP in RPMC showed a significant increase compared with that of control cells. In addition, ABWE significantly inhibited compound 48/80-induced cAMP reduction in RPMC. These results propose that ABWE may be beneficial in the treatment of mast cell-mediated anaphylactic reactions.

Effects of peptides, with emphasis on feeding, pain, and behavior A 5-year (1999-2003) review of publications in Peptides

Novel effects of naturally occurring peptides are continuing to be discovered, and their mechanisms of actions as well as interactions with other substances, organs, and systems have been elucidated. Synthetic analogs may have actions similar or antagonistic to the endogenous peptides, and both the native peptides and analogs have potential as drugs or drug targets. The journal Peptides publishes many leading articles on the structure-activity relationship of peptides as well as outstanding reviews on some families of peptides. Complementary to the reviews, here we extract information from the original papers published during the past five years in Peptides (1999-2003) to summarize the effects of different classes of peptides, their modulation by other chemicals and various pathophysiological states, and the mechanisms by which the effects are exerted. Special attention is given to peptides related to feeding, pain, and other behaviors. By presenting in condensed form the effects of peptides which are essential for systems biology, we hope that this summary of existing knowledge will encourage additional novel research to be presented in Peptides.

Venom effects on monoaminergic systems

The monoamines, dopamine, epinephrine, histamine, norepinephrine, octopamine, serotonin and tyramine serve many functions in animals. Many different venoms have evolved to manipulate monoaminergic systems via a variety of cellular mechanisms, for both offensive and defensive purposes. One common function of monoamines present in venoms is to produce pain. Some monoamines in venoms cause immobilizing hyperexcitation which precedes venom-induced paralysis or hypokinesia. A common function of venom components that affect monoaminergic systems is to facilitate distribution of other venom components by causing vasodilation at the site of injection or by increasing heart rate. Venoms of some scorpions, spiders, fish and jellyfish contain adrenergic agonists or cause massive release of catecholamines with serious effects on the cardiovascular system, including increased heart rate. Other venom components act as agonists, antagonists or modulators at monoaminergic receptors, or affect release, reuptake or synthesis of monoamines. Most arthropod venoms have insect targets, yet, little attention has been paid to possible effects of these venoms on monoaminergic systems in insects. Further research into this area may reveal novel effects of venom components on monoaminergic systems at the cellular, systems and behavioral levels.