Proteinase-activated receptor-2 (PAR-2) expression has been observed on numerous cell types. However, little is known about the functional expression of PAR-2 in human mast cells. In the current study, the actions of a PAR-2 agonist trans-cinnamoyl-Leu-Ile-Gly-Arg-Leu-Orn-amide (tc-LIGRLO) on tryptase release from dispersed human colonic mast cells were examined. The results showed that tc-LIGRLO was able to induce a fold increase in tryptase release over the basal level following a 15 min incubation of colonic mast cells, whereas tc-OLRGIL did not have any effect on tryptase release. The potency of tc-LIGRLO appeared greater than that of anti-IgE and calcium ionophore A23187 (CI) in induction of tryptase release. Extending the incubation time to 30 min had no significant effect on the actions of tc-LIGRLO or anti-IgE. In the time course study, it was observed that the tryptase release from mast cells induced by tc-LIGRLO started at 1 min and peaked at 3 min following incubation. The above-mentioned results indicate that tc-LIGRLO is a potent stimulus of tryptase release from human mast cells, which strongly suggests that PAR-2s are expressed in human mast cells.
Cells, Cultured ; Humans ; Mast Cells ; drug effects ; metabolism ; Receptor, PAR-2 ; agonists ; Tryptases ; metabolism

Mast cell which is considered to participate in immune response has long been studied. However its true role in center nervous system is still unknown. Recently,mast cell has been found to play an important function during the process of multiple sclerosis and Wernicke's encephalopathy in the brain. Multiple sclerosis is an inflammatory demyelinating disease, and Wernicke's encephalopathy is caused by deficiency of thiamine. Mast cell deteriorates the neuronal damage and the course of diseases by their mediators. Such studies may supply new idea on the therapy of these diseases.
Animals ; Brain ; pathology ; Humans ; Mast Cells ; metabolism ; pathology ; Multiple Sclerosis ; metabolism ; pathology ; Wernicke Encephalopathy ; metabolism ; pathology

AIMTo examine the ability of calcium ionophore (CI) to induce tryptase and histamine release from human mast cells and its mechanisms.

METHODSEnzymatically dispersed cells from human colons were challenged with CI, and the cell supernatants after challenge were collected. Tryptase release was determined with a sandwich ELISA procedure and histamine release was measured using a glass fibre-based fluorometric assay.

RESULTSCI was able to induce a concentration dependent release of histamine and tryptase from human colon mast cells following 15 min incubation. The maximum of induced histamine and tryptase release were approximately 5.3 and 2.8 fold more than the levels of spontaneous release, respectively. CI at the concentrations higher than 1.0 micromol/L was able to induce significantly more histamine than tryptase release from mast cells. The time course revealed that the action of CI on mast cells started from 10 s, peaked at 6 min and lasted at least 15 min following incubation. Pertussis toxin and metabolic inhibitors were able to inhibit mast cell response to CI.

CONCLUSIONHuman colon mast cells were able to release tryptase and histamine in response to CI. The process seemed to be associated with the activation of a G-protein coupled receptor on the membrane of mast cells and requires cell energy supply.

Calcium Ionophores ; pharmacology ; Cells, Cultured ; Colon ; cytology ; Histamine ; metabolism ; Humans ; Mast Cells ; drug effects ; metabolism ; secretion ; Tryptases ; metabolism

Endometriosis (EMs) is a common gynecologic disease that affects women's physical and mental health seriously. The pathogenesis is still unknown and the mechanism of endometriosis-associated pain remains unclear. Mast cells (MC) are known to be multifunctional players in the immune system. Recent studies have shown that nerve fibers in EMs lesions can release neural peptides such as nerve growth factor and substance P to induce MC degranulating and releasing histamine, proteases, cytokines, chemokines etc., which contributes to the development of pain and hyperalgesia in patients with endometriosis.
Endometriosis ; complications ; metabolism ; pathology ; Female ; Humans ; Mast Cells ; metabolism ; Nerve Growth Factor ; metabolism ; Pelvic Pain ; etiology ; pathology

OBJECTIVETo investigate the influence of the bone marrow-derived mast cells (BMMCs) on the expression of type II collagen and glycosaminoglycan (GAG) in chondrocytes co-cultured with BMMCs.

METHODSPrimarily cultured mouse BMMCs at 4 weeks and the second passage of chondrocytes were plated in a Transwell co-cultured system at a ratio of 1:10 in the presence or absence of sodium cromoglycate (DSCG) or compound 48/80 (C48/80). The chondrocytes were harvested and lysed for detecting type II collagen expression with ELISA and Western blotting and GAG expression using 1,9 dimethylmethylene blue (DBM).

RESULTSAfter a 24-hour culture, the chondrocytes co-cultured with BMMCs showed similar expression levels of type II collagen and GAG to the control group regardless of the presence of DSCG (P>0.05). Compared with chondrocytes cultured alone or with BMMCs, the co-cultured chondrocytes in the presence of C48/80 showed significantly lower expressions of type II collagen and GAG (P<0.01). Such results did not vary significantly as the culture time was extended to 48 h.

CONCLUSIONC48/80-activated BMMCs can reduce the expression of type II collagen and GAG in chondrocytes in the co-culture system.

Animals ; Bone Marrow Cells ; cytology ; Cells, Cultured ; Chondrocytes ; cytology ; Coculture Techniques ; Collagen Type II ; metabolism ; Glycosaminoglycans ; metabolism ; Mast Cells ; cytology ; Mice

OBJECTIVETo explore the quantity of mast cells and the role of protease activated receptor-2 (PAR-2) in experimental rat liver fibrosis.

METHODSRats were sacrificed at 0, 2, 4, 8, and 12 weeks after subcutaneous injection of CCl(4). Mast cells were displayed by toluidine blue stain. The content of liver hydroxyproline was measured by the method of base hydrolyzate. The mRNA expression and the protein expression of PAR-2 in livers were detected by RT-PCR and immunohistochemistry at each time point.

RESULTSIn normal rat livers there were a few mast cells (2.5+/-1.0) distributed along the hepatic portal areas. In the cirrhosis model group the number of mast cells in the livers increased degree by degree (2 weeks vs 4 weeks vs 8 weeks, 9.1+/-0.5 vs 15.7+/-3.0 vs 32.0+/-3.3; P less than 0.05), and they were distributed densely around the hepatic portal areas and the central veins. The content of liver hydroxyproline increased progressively from 0 to 12 weeks. In normal livers PAR-2 mRNA was hardly detected, at 2 weeks there was some expression of PAR-2 mRNA (PAR-2/beta-actin 0.15+/-0.01, P less than 0.05), at 4 weeks its expression increased (PAR-2/beta-actin 0.35+/-0.02, P less than 0.05) and it maintained a higher level (PAR-2/beta-actin 0.80+/-0.02, P less than 0.05) since then. The changing trend of the protein expression of PAR-2 was the same as that of PAR-2 mRNA expression.

CONCLUSIONSPAR-2 mRNA expression and the protein expression of PAR-2 were consistent with the increase of the mast cells, and the content of liver hydroxyproline may play an important role in mediating liver fibrosis.

Animals ; Hydroxyproline ; metabolism ; Liver ; metabolism ; Liver Cirrhosis, Experimental ; metabolism ; Male ; Mast Cells ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptor, PAR-2 ; metabolism

Trichomonas vaginalis is a flagellated protozoan parasite that causes vaginitis and cervicitis in women and asymptomatic urethritis and prostatitis in men. Mast cells have been reported to be predominant in vaginal smears and vaginal walls of patients infected with T. vaginalis. Mitogen-activated protein kinase (MAPK), activated by various stimuli, have been shown to regulate the transcriptional activity of various cytokine genes in mast cells. In this study, we investigated whether MAPK is involved in ROS generation and exocytotic degranulation in HMC-1 cells induced by T. vaginalis-derived secretory products (TvSP). We found that TvSP induces the activation of MAPK and NADPH oxidase in HMC-1 cells. Stimulation with TvSP induced phosphorylation of MAPK and p47phox in HMC-1 cells. Stimulation with TvSP also induced up-regulation of CD63, a marker for exocytosis, along the surfaces of human mast cells. Pretreatment with MAPK inhibitors strongly inhibited TvSP-induced ROS generation and exocytotic degranulation. Finally, our results suggest that TvSP induces intracellular ROS generation and exocytotic degranulation in HMC-1 via MAPK signaling.
Cell Degranulation ; Cell Line ; *Exocytosis ; Humans ; Mast Cells/*drug effects/*metabolism ; Mitogen-Activated Protein Kinases/*metabolism ; Reactive Oxygen Species/*metabolism ; Trichomonas vaginalis/*metabolism ; Virulence Factors/*metabolism

OBJECTIVE: To investigate the distribution of mast cells in nasal polyps. METHOD: Biopsy specimens from patients with nasal polyps (n = 20) and control patients (n = 8) were obtained and included in this study. The distribution of mast cells in nasal polyps and the expression of chemokines (CCL5, CCL11, CX3CL1, IL-8, IL-6) in the epithelial cells of normal nasal mucosa and nasal polyps was determined by immunohistochemistry. RESULT: Mast cells migrate to intraepithelial in nasal polyps and the expression of chemokines (CCL5, CCL11, CX3CL1, IL-8) was up regulated in the epithelial cells of nasal polyps compare to normal nasal mucosa. CONCLUSION Our findings showed that mast cells migrate to intraepithelial in nasal polyps and the over expression of chemotaxins (CCL5, CCL11, CX3CL1, IL-8) may be response for mast cells' migration in nasal polyps. Mast cells might be associated with the development of nasal polyps.
Chemokine CCL11 ; metabolism ; Chemokine CCL5 ; metabolism ; Chemokine CX3CL1 ; metabolism ; Epithelial Cells ; metabolism ; Humans ; Immunohistochemistry ; Interleukin-6 ; metabolism ; Interleukin-8 ; metabolism ; Mast Cells ; metabolism ; pathology ; Nasal Mucosa ; cytology ; metabolism ; Nasal Polyps ; metabolism ; pathology ; Up-Regulation

OBJECTIVETo investigate whether connective tissue growth factor (CGGF) is expressed in mast cells (MCs) in lung in the development of bleomycin (BLM)-induced pulmonary fibrosis.

METHODSThirty-two male SD rats were randomly divided into 2 groups: BLM group and control group (n=16). The rats in BLM group were received single intratracheal instillation of BLM (5 mg/kg), and the rats in control group received equal volume of 0.9% normal saline(NS) to BLM. The rats in each group were sacrificed for lung tissue sampling on day 14 and day 28 after intratracheal instillation respectively. As the index of the severity of pulmonary fibrosis, the content of hydroxyproline in lungs was analyzed by chloramine T method. Mast cells and CTGF expression in lungs were examined by toluidine blue stain and immunohistochemical assay respectively.

RESULTS(1) On day 28 after intratracheal instillation of BLM, the content of hydroxyproline in lungs of rats was higher than that of control rats (P < 0.01). (2) Compared to control rats, the rats on day 14 and day 28 after instillation of BLM showed increased number of mast cells (Both P < 0.01) and up-regulated CTGF expression (Both P < 0.01). (3) No CTGF immuno-positive MCs were seen in the lungs of control rats whereas CTGF immuno-positive MCs were observed in the pathological areas in lungs of rats on day 14 and day 28 after BLM.

CONCLUSIONCTGF is expressed in MCs in lungs in the development of pulmonary fibrosis, which might be one of the mechanisms underling promoting effect of MCs on fibrosis in lung.

Animals ; Bleomycin ; Connective Tissue Growth Factor ; metabolism ; Lung ; metabolism ; pathology ; Male ; Mast Cells ; metabolism ; Pulmonary Fibrosis ; chemically induced ; metabolism ; Rats ; Rats, Sprague-Dawley

OBJECTIVE: To observe the effect of electroacupuncture (EA) preconditioning on the expressions of tyrosine kinase Lyn and spleen tyrosine kinase (Syk) in mast cells of subcutaneous loose connective tissue in the rats with urticaria and explore the potential biological mechanism of EA in the intervention of urticaria. METHODS: A total of 32 SD rats were randomized into a blank group, a model group, an EA group and a positive medication group, 8 rats in each one. Except of the blank group, the passive cutaneous anaphylaxis (PCA) was adopted to prepare the model of urticaria in the rats of the rest three groups. In the EA group, EA was applied to bilateral "Quchi" (LI 11), "Xuehai" (SP 10) and "Zusanli" (ST 36), with disperse-dense wave, 2 Hz/15 Hz in frequency and 1 mA in current intensity, once daily, for 20 min each time, consecutively for 7 days. In the positive medication group, loratadine (1 mg•kg•d) was for intragastric administration, once daily, consecutively for 7 days. The samples were collected for index detection 30 min after PCA antigen challenge in the rats of each group. Spectrophotometer was adopted to determine the effusion quantity of Evans blue in the allergized site of skin. HE staining was used to observe the morphological changes in the allergized site of skin. Toluidine blue staining was provided to observe mast cell degranulation in subcutaneous loose connective tissue in the allergized site of skin. Immunohistochemistry was applied to determine the protein expressions of Lyn and Syk during degranulation of mast cells. RESULTS: In the rats of the odel group, the eipdermis of allergized site was thickening, cells were disorganized in hierarchy and inflammatory cells were infiltrated largely in the dermis. In the positive medication group and the EA group, the epidermis was getting thin, cell arrangement was clear and the inflammatory cell infiltration was obviously alleviated as compared with the model group. Compared with the blank group, the OD value of skin dye effusion quantity, the degranulation rate of mast cells and the positive expressions of Lyn and Syk were all increased in the model group (<0.01). Compared with the model group, the OD value of skin dye effusion quantity, the degranulation rate of mast cells and the positive expressions of Lyn and Syk were all reduced in the EA group and the positive medication group (<0.01). Compared with the positive medication group, the degranulation rate of mast cells was increased significantly in the EA group (<0.01). CONCLUSION Electroacupuncture at "Quchi" (LI 11), "Xuehai" (SP 10) and "Zusanli" (ST 36) reduces vascular permeability and gives play to the role of anti-allergy by the way of regulating and controlling the degranulation of mast cells in the rats with urticaria and the effect mechanism of electroacupuncture may be related to the inhibition of protein expressions of Lyn and Syk in mast cells.
Acupuncture Points ; Animals ; Connective Tissue ; metabolism ; Electroacupuncture ; Mast Cells ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Syk Kinase ; metabolism ; Urticaria ; therapy ; src-Family Kinases ; metabolism