Síndrome de microdeleção 2q32 em paciente da Amazônia ocidental / 2q32 microdeletion syndrome in a patient from the western Amazon

Introdução: As deleções intersticiais envolvendo a região 2q31q32 são reconhecidas como um transtorno clínico, envolvendo diversas manifestações como deficiência intelectual, retardo no crescimento, distúrbios comportamentais e dismorfologias faciais. Os números reduzidos de relatos de pacientes acometidos por essa síndrome contribui para que as correlações genótipos-fenótipos sejam difíceis de se fazer. Relato de caso: Paciente com inversão do braço longo do cromossomo 2 [46, XX,inv(2)(q21q33)]. Apresentou ao exame físico dismorfológico fronte proeminente, epicanto, ponte nasal baixa, filtro nasolabial longo e lábio superior fino. Ao exame neurológico, apresentava hipotonia. Discussão: Uma correta interpretação cromossômica pode não só identificar a síndrome de microdeleção como também, descartar ou confirmar possíveis diagnósticos diferenciais, deixando evidente a necessidade e a importância de se reconhecer e documentar os casos (AU).

Introduction: Interstitial deletions involving the 2q31q32 region are recognized as a clinical disorder involving several manifestations, such as intellectual disability, growth retardation, behavioral disorders, and facial dysmorphologies. The reduced number of reports of patients affected by this syndrome contributes to the difficulty of making genotype-phenotype correlations. Case report: Patient with inversion of the long arm of chromosome 2 [46, XX,inv(2)(q21q33)]. On physical examination, he had a prominent forehead, epicanthus, low nasal bridge, long nasolabial philtrum and thin upper lip. Neurological examination showed hypotonia. Discussion: A correct chromosomal interpretation can identify the microdeletion syndrome and rule out or confirm possible differential diagnoses, highlighting the need and importance of recognizing and documenting cases (AU).

Proteolytic activity of Triatoma infestans saliva associated with PAR-2 activation and vasodilation

Triatoma infestans (Hemiptera: Reduviidae) is a hematophagous insect and the main vector of Trypanosoma cruzi (Kinetoplastida: Trypanosomatidae). In the present study, the authors investigated whether a serine protease activity from the saliva of T. infestans has a role in vasomotor modulation, and in the insect-blood feeding by cleaving and activating protease-activated receptors (PARs). Methods T. infestans saliva was chromatographed as previously reported for purification of triapsin, a serine protease. The cleavage activity of triapsin on PAR peptides was investigated based on FRET technology. Mass spectrometry was used to analyze the sites of PAR-2 peptide cleaved by triapsin. NO measurements were performed using the DAN assay (2,3-diaminonapthalene). The vasorelaxant activity of triapsin was measured in vessels with or without functional endothelium pre-contracted with phenylephrine (3 µM). Intravital microscopy was used to assess the effect of triapsin on mouse skin microcirculation. Results Triapsin was able to induce hydrolysis of PAR peptides and showed a higher preference for cleavage of the PAR-2 peptide. Analysis by mass spectrometry confirmed a single cleavage site, which corresponds to the activation site of the PAR-2 receptor. Triapsin induced dose-dependent NO release in cultured human umbilical vein endothelial cells (HUVECs), reaching a maximum effect at 17.58 nM. Triapsin purified by gel-filtration chromatography (10-16 to 10-9 M) was applied cumulatively to mouse mesenteric artery rings and showed a potent endothelium-dependent vasodilator effect (EC30 = 10-12 M). Nitric oxide seems to be partially responsible for this vasodilator effect because L-NAME (L-NG-nitroarginine methyl ester 300 µM), a nitric oxide synthetase inhibitor, did not abrogate the vasodilation activated by triapsin. Anti-PAR-2 antibody completely inhibited vasodilation observed in the presence of triapsin activity. Triapsin activity also induced an increase in the mouse ear venular diameter. Conclusion Data from this study suggest a plausible association between triapsin activity mediated PAR-2 activation and vasodilation caused by T. infestans saliva.(AU)

Effect of protease activated receptor 2 on colonic motility in diabetes mice / 上海交通大学学报（医学版）

Objective • To observe the effect of protease activated receptor 2 (PAR2) on the colonic motility in diabetic mice and investigate the mechanism. Methods • The mouse model of type 1 diabetes mellitus was established by intraperitoneal injection of streptozotocin. The smooth muscle strips and segments of colons were isolated. The effects of PAR2 agonist on colonic motility were observed by muscle strip tension contraction and colonic migrating motor complex experiments. The effect of small conductance calcium-activated potassium channel (SK3 channel) antagonist on it was also observed. Results • PAR2 agonist inhibited colonic motility and colonic smooth muscle was more sensitive to PAR2 agonist in diabetic mice. PAR2 agonist-induced inhibition was inhibited by SK3 channel antagonist. Conclusion • PAR2 activity in diabetic mice colons is significantly enhanced, which may inhibit colonic motility through SK3 channel.

Effect of tacrolimus on the expression and function of protease-activated receptor 2 in human keratinocytes / 中华皮肤科杂志

Objective@#To evaluate the in vitro effect of tacrolimus on the expression and function of protease-activated receptor 2 (PAR-2) in cultured human keratinocytes.@*Methods@#After 24-hour co-culture of human keratinocytes with 10-9 - 10-5 mol/L tacrolimus, semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) was performed to determine the mRNA expression of PAR-2, immunofluorescence (IF) staining and Western blot analysis were performed to determine the protein expression of PAR-2 in the keratinocytes, and the fluorescent calcium probe fluo-4 was used to evaluate the effect of tacrolimus at different concentrations on the intracellular calcium concentration after the activation of PAR-2 in the keratinocytes. The group treated without tacrolimus served as control group. One-way analysis of variance was used to compare the PAR-2 expression and calcium concentration in the human keratinocytes in different groups, and least significant difference (LSD) -t test was carried out for multiple comparisons.@*Results@#PAR-2 was expressed on both the membrane and cytoplasm of keratinocytes. After 24-hour co-culture of keratinocytes with 10-9 - 10-5 mol/L tacrolimus, the PAR-2 mRNA expression significantly decreased in these cells compared with the control group (all P < 0.05) , and was negatively correlated with the tacrolimus concentration (r=-0.962, P = 0.009) . IF staining and Western blot analysis showed that the PAR-2 protein expression was significantly lower in the 10-5- and 10-6-mol/L tacrolimus groups than in the control group (both P < 0.05) , and decreased to a certain extent in the 10-7-mol/L tacrolimus group (IF staining: P < 0.05; Western blot analysis: P > 0.05) . No significant difference in the PAR-2 protein expression was observed between the 10-8- or 10-9-mol/L tacrolimus group and the control group (both P > 0.05) . After 24-hour co-culture, the peak concentration of intracellular calcium after PAR-2 activation was significantly lower in the 10-5-, 10-6- and 10-7-mol/L tacrolimus groups (peak absorbance: 1 463 ± 283, 1 455 ± 270, 1 423 ± 291 respectively) than in the control group (1 602 ± 407; t = 2.582, 2.821, 2.923, P = 0.032, 0.022, 0.019, respectively) , while there was no significant difference between the 10-8- or 10-9-mol/L tacrolimus group (1 649 ± 379, 1 633 ± 415 respectively) and the control group (t = 0.846, 0.462, P = 0.422, 0.657, respectively) .@*Conclusion@#Tacrolimus can inhibit PAR-2 expression and suppress calcium mobilization induced by a PAR-2 agonist in keratinocytes.

Effect of tacrolimus on the expression and function of protease-activated receptor 2 in human keratinocytes / 中华皮肤科杂志

Objective To evaluate the in vitro effect of tacrolimus on the expression and function of protease-activated receptor 2(PAR-2)in cultured human keratinocytes. Methods After 24-hour co-culture of human keratinocytes with 10-9-10-5 mol/L tacrolimus, semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR)was performed to determine the mRNA expression of PAR-2, immunofluorescence(IF)staining and Western blot analysis were performed to determine the protein expression of PAR-2 in the keratinocytes, and the fluorescent calcium probe fluo-4 was used to evaluate the effect of tacrolimus at different concentrations on the intracellular calcium concentration after the activation of PAR-2 in the keratinocytes. The group treated without tacrolimus served as control group. One-way analysis of variance was used to compare the PAR-2 expression and calcium concentration in the human keratinocytes in different groups, and least significant difference(LSD)-t test was carried out for multiple comparisons. Results PAR-2 was expressed on both the membrane and cytoplasm of keratinocytes. After 24-hour co-culture of keratinocytes with 10 - 9- 10 - 5 mol/L tacrolimus, the PAR-2 mRNA expression significantly decreased in these cells compared with the control group(all P < 0.05), and was negatively correlated with the tacrolimus concentration(r=-0.962, P=0.009). IF staining and Western blot analysis showed that the PAR-2 protein expression was significantly lower in the 10-5- and 10-6-mol/L tacrolimus groups than in the control group (both P < 0.05), and decreased to a certain extent in the 10-7-mol/L tacrolimus group(IF staining:P<0.05;Western blot analysis:P>0.05). No significant difference in thePAR-2 protein expression was observed between the 10-8-or 10-9-mol/L tacrolimus group and the control group(both P>0.05). After 24-hour co-culture, the peak concentration of intracellular calcium after PAR-2 activation was significantly lower in the 10-5-, 10-6- and 10-7-mol/L tacrolimus groups (peak absorbance:1463 ± 283, 1455 ± 270, 1423 ± 291 respectively)than in the control group(1602 ± 407;t=2.582, 2.821, 2.923, P=0.032, 0.022, 0.019, respectively), while there was no significant difference between the 10-8-or 10-9-mol/L tacrolimus group(1649 ± 379, 1633 ± 415 respectively)and the control group(t=0.846, 0.462, P=0.422, 0.657, respectively). Conclusion Tacrolimus can inhibit PAR-2 expression and suppress calcium mobilization induced by a PAR-2 agonist in keratinocytes.

Effect of inhibition of PAR2?PKA/PKCε signaling pathway in periphery neurons on the transition from acute to chronic pain / 中国实验动物学报

Objective To detect the role of PAR2-PKA/PKCε signaling pathway in periphery neurons in the tran-sition from acute to chronic pain,and investigate the possible approach to prevent both acute and chronic pain simultane-ously. Methods SD rats were randomly divided into control group,sham model group,model group,iPAR2-1 group and iPAR2-2 group. The hyperalgesia priming model was established by injection of carrageenan and PGE2 into the left hind-paw except control and sham model group. PGE2 was administrated at 7 days after carrageenan injection. The PAR2 inhibi-tor was administrated before and after PGE2 injection separately in the iPAR2-1 group and iPAR2-2 group. The paw with-drawal thresholds(PWTs)of rats in each group was detected before and at 5 h,3 d,6 d,7 d 0.5 h,7 d 4 h,7 d 24 h after carrageenan injection. The expression level of PAR2, PKA and PKCε proteins in the dorsal root ganglion(DRG) were detected at 24 h after carrageenan injection. Results The hyperalgesia priming model was successfully generated. When PGE2 was administrated at 7 days after carrageenan injection, the hyperalgesia induced by PGE2 was significantly prolonged. The PWTs of rats in the model group were significantly lower than that of the control and sham model groups(P<0.01),though the PWTs of sham model group had no significant difference with the control on 7 d 24 h after carrageenan injection(P>0.05). The expression level of PAR2 and PKCε in the ipsilateral DRG neurons were significantly increased on 7 d 24 h after carrageenan injection,when compared with the control and sham model groups(P<0.05). PAR2 inhibi-tor prevented the prolonged hyperalgesia induced by PGE2(P<0.05)and decreased the PKCε expression in DRG neurons whenever it was given(P<0.05). However,PAR2 inhibitor did not regulate the acute inflammatory pain of PGE2 and the expression of PKA in DRG neurons(P>0.05). Conclusions Inhibition of the expression of PAR2 can prevent the tran-sition from acute to chronic pain. This effect may be related with the inhibitory effect on the activation of PAR2-PKCε sig-naling pathway in DRG neurons. However,inhibition of PAR2 can not regulate the acute pain. These may because of that the PAR2-PKA signaling pathway does not play a role in acute pain.

Role of H1R, PAR-2/TRPV1 itch signal pathway on acute eczema and mechanism study of Portulaca extracts / 中国免疫学杂志

Objective:To investigate the influence of Portulaca extracts on H1R,PAR-2 and TRPV1 in skins of rats and the regulation mechanism of H1R,PAR-2/TRPV1 itch signal pathway with atopic eczema.Methods:30 SD rats were randomly divided into normal control group,model group and Porulaca group,each group contained 10 rats.In addition to the normal group,2,4-dinitrochloro-benzene was used on the rest of group for making rat model with atopic eczema.After the success of the model manufacture,each group was given corresponding drugs.After the last administration,EASI was evaluated.The levels of H1R,PAR-2 and TRPV1 in rats skins were detected by immunohistochemical method.Ca2+concentration was analyzed by flow cytometry.Results: Compared with normal control group,EASI(P<0.01),the levels of H1R(P<0.05) and PAR-2(P<0.01),and Ca2+concentration(P<0.01) of rats in model group were significantly increased.The levels of TRPV1 were not increased obviously (P>0.05).Compared with model group,EASI (P<0.01),the levels of H1R(P<0.01) and PAR-2(P<0.01),and Ca2+concentration(P<0.05) of rats in Porulaca group were sig-nificantly reduced,and the levels of TRPV1 were not decreased obviously(P>0.05).Conclusion:Purslane could reduce the levels of H1R,PAR-2 and Ca2+concentration to treat the acute eczema.The mechanism may be to lose the activation of downstream molecule TRPV1 and reduce the inflow of Ca2+by reducing the levels of upstream molecules H1R and PAR-2,then to achieve the effect of anti itch.

Electroacupuncture Relieves Visceral Hypersensitivity by Down-regulating Mast Cell Number，PAR-2/TRPV 1 Signaling, etc. in Colonic Tissue of Rats with Irritable Bowel Syndrome / 针刺研究

OBJECTIVE: To observe the effect of electroacupuncture (EA) stimulation of "Shangjuxu" (ST 37, Lower Confluent point) and "Tianshu" (ST 25, Front-Mu point) on visceral pain and expression of colonic tryptase(Try), proteinase-activated receptor 2(PAR-2)，transient receptor potential channel vanilloid subfamily member 1 (TPRV 1)，substance P (SP) and calcitonin gene-related peptide (CGRP) in rats with irritable bowel syndrome (IBS), so as to explore its mechanisms underlying improvement of IBS. METHODS: Forty male Sprague Dawley rats were equally randomized into normal control (control), model, medication and EA groups (n＝10 in each). The IBS model was established by chronic acute combining stress (CACS, water deprivation, fasting, tail clamping, forced swimming in ice water, restraint, etc.) for 21 days. Rats of the medication group were treated by gavage of Pinaverium Bromide (1 mg/mL, 15 mg/kg), once daily for 14 d. EA (10 Hz/50 Hz, 0.2－0.3 mA) was applied to bilateral ST 37 and ST 25 for 30 min, once daily for 14 d. The muscular withdrawal reflex (AWR) of both abdomen and buttock was detected by colorectal distension (CRD) with a water-filled balloon for examining the visceral hypersensitivity. The number of mast cells in the colonic tissue was counted after toluidine blue stain. The immunoactivity of colonic Try was determined by immunochemistry and the expression of colonic PAR-2, TRVP 1, SP and CGRP proteins detected by Western blot. RESULTS: After modeling, the body weight was significantly decreased in IBS rats of the model, medication and EA groups compared with their own individual pre-treatment and with the control group (P0.05)．. CONCLUSION: EA of ST 37 and ST 25 can relieve visceral hypersensitivity in IBS rats, which may be associated with its effects in down-regulating the number of MC and the expression of PAR-2, TRVP 1, SP, CGRP and Try proteins in the colonic tissue.

Expression and significance of PAR2 and TMEM16A on DRG rat modelin of neuropathic pain / 实用医学杂志

Objective To observe the expression of PAR2 and TMEM16A in the model of chronic constriction injury (CCI) in rat dorsal root ganglion (DRG) neurons,and to explore the role of it in the neuropathic pain.Methods Rats were divided into Sham operation group (Sham) and CCI group.Both groups were observed respectively to determine thermal withdrawal latency (TWL).The expression of PAR2 and TMEM16A in the dorsal root ganglion of the rat was analyzed using Western blot and immunofluorescence.Results The difference in preoperative TWL between CCI group and Sham group rats was not statistically significant (P ＜ 0.01).TWL was signifi cantly lower at all other time points after operation (P ＜ 0.01).Immunofluorescence results showed that PAR2 and TMEM16A coexisted in rat DRG neurons.Western blot results showed that,compared with Sham group,CCI group PAR2 and TMEM16A protein expression significantly increased after 7 d and 14 d (P ＜ 0.01),and the PAR2 and TMEM16A protein expression on 14 d is higher than that of 7 d (P ＜ 0.05).Conclusions Expression level of PAR2 and TMEM16A in CCI group was significantly higher than those in Sham group.The expression level of these proteins may be the cause of rat model of neuropathic pain.

PAR-2 expression in the gingival crevicular fluid reflects chronic periodontitis severity

Abstract Recent studies investigating protease-activated receptor type 2 (PAR-2) suggest an association between the receptor and periodontal inflammation. It is known that gingipain, a bacterial protease secreted by the important periodontopathogen Porphyromonas gingivalis can activate PAR-2. Previous studies by our group found that PAR-2 is overexpressed in the gingival crevicular fluid (GCF) of patients with moderate chronic periodontitis (MP). The present study aimed at evaluating whether PAR-2 expression is associated with chronic periodontitis severity. GCF samples and clinical parameters, including plaque and bleeding on probing indices, probing pocket depth and clinical attachment level, were collected from the control group (n = 19) at baseline, and from MP patients (n = 19) and severe chronic periodontitis (SP) (n = 19) patients before and 6 weeks after periodontal non-surgical treatment. PAR-2 and gingipain messenger RNA (mRNA) in the GCF of 4 periodontal sites per patient were evaluated by Reverse Transcription Polymerase Chain Reaction (RT-qPCR). PAR-2 and gingipain expressions were greater in periodontitis patients than in control group patients. In addition, the SP group presented increased PAR-2 and gingipain mRNA levels, compared with the MP group. Furthermore, periodontal treatment significantly reduced (p <0.05) PAR-2 expression in patients with periodontitis. In conclusion, PAR-2 is associated with chronic periodontitis severity and with gingipain levels in the periodontal pocket, thus suggesting that PAR-2 expression in the GCF reflects the severity of destruction during periodontal infection.

Skin Barrier Recovery by Protease-Activated Receptor-2 Antagonist Lobaric Acid

Atopic dermatitis (AD) results from gene and environment interactions that lead to a range of immunological abnormalities and breakdown of the skin barrier. Protease-activated receptor 2 (PAR2) belongs to a family of G-protein coupled receptors and is expressed in suprabasal layers of the epidermis. PAR2 is activated by both trypsin and a specific agonist peptide, SLIGKV-NH₂ and is involved in both epidermal permeability barrier homeostasis and epithelial inflammation. In this study, we investigated the effect of lobaric acid on inflammation, keratinocyte differentiation, and recovery of the skin barrier in hairless mice. Lobaric acid blocked trypsin-induced and SLIGKV-NH₂-induced PAR2 activation resulting in decreased mobilization of intracellular Ca²⁺ in HaCaT keratinocytes. Lobaric acid reduced expression of interleukin-8 induced by SLIGKV-NH₂ and thymus and activation regulated chemokine (TARC) induced by tumor necrosis factor-a (TNF-α) and IFN-γ in HaCaT keratinocytes. Lobaric acid also blocked SLIGKV-NH₂-induced activation of ERK, which is a downstream signal of PAR2 in normal human keratinocytes (NHEKs). Treatment with SLIGKV-NH₂ downregulated expression of involucrin, a differentiation marker protein in HaCaT keratinocytes, and upregulated expression of involucrin, transglutamase1 and filaggrin in NHEKs. However, lobaric acid antagonized the effect of SLIGKV-NH₂ in HaCaT keratinocytes and NHEKs. Topical application of lobaric acid accelerated barrier recovery kinetics in a SKH-1 hairless mouse model. These results suggested that lobaric acid is a PAR2 antagonist and could be a possible therapeutic agent for atopic dermatitis.

Tryptase and Protease-Activated Receptor 2 Expression Levels in Irritable Bowel Syndrome

BACKGROUND/AIMS: Previous studies have revealed that mast cells (MCs) may activate the protease-activated receptors and release of neuropeptides involved in the pathogenesis of irritable bowel syndrome (IBS). The levels of protease-activated receptor 2 (PAR-2) and tryptase can contribute to understanding the pathogenesis of IBS. METHODS: Colonoscopic biopsies were performed of 38 subjects (20 with IBS-diarrhea [IBS-D], eight with IBS-constipation [IBS-C], and 10 healthy volunteers). The mRNA and protein levels of tryptase and PAR-2 were assessed by real-time PCR and Western blot. The levels of vasoactive intestinal peptide (VIP), substance P (SP), and calcitonin gene-related peptide (CGRP) were measured by immunohistochemistry, and MCs were counted by toluidine blue staining. RESULTS: Significant increases in the mRNA expression of tryptase (p<0.05, IBS-D, IBS-C vs control) and PAR-2 (p<0.05, IBS-D, IBS-C vs control) and in the tryptase protein level (p<0.05, IBS-D, IBS-C vs control) were detected in IBS. Elevations of MCs, CGRP, VIP and SP (p<0.05, IBS-D vs control) were observed for IBS-D only. CONCLUSIONS: Tryptase levels may upregulate the function of PAR-2, resulting in the release of neuropeptide and they were correlated with clinical symptoms associated with IBS.

Increased Expression of Cathelicidin by Direct Activation of Protease-Activated Receptor 2: Possible Implications on the Pathogenesis of Rosacea

PURPOSE: Recent findings of increased cathelicidin protein and its proteolytic fragments in rosacea suggest a pathogenic role for cathelicidin in this disease. The relationship between cathelicidin and protease-activated receptor 2 (PAR-2) is therefore of interest, as PAR-2, expressed principally in keratinocytes, regulates pro-inflammatory cytokine expression in the skin. The purpose of this study was to determine the relationship between expression of PAR-2 and cathelicidin in rosacea and to test the effect of direct PAR-2 activation on cathelicidin expression in keratinocytes. MATERIALS AND METHODS: Samples from 40 patients with clinicopathologic diagnosis of rosacea and facial skin tissue samples from 20 patients with no specific findings or milium without inflammation were retrieved. Intensities of immunohistochemical staining for PAR-2 and cathelicidin were compared between normal and rosacea-affected skin tissues. Additionally, correlations between PAR-2 and cathelicidin staining intensities within rosacea patients were analyzed. In cultured keratinocytes, changes in PAR-2, cathelicidin, and vascular endothelial growth factor (VEGF) mRNA and protein were analyzed after treatment with PAR-2 activating peptide (AP). RESULTS: Cathelicidin expression was significantly higher in rosacea skin tissues than in normal tissues (p<0.001), while PAR-2 expression was not significantly higher in rosacea tissues than in normal skin tissues. A positive correlation between PAR-2 and cathelicidin within rosacea samples was observed (R=0.330, p=0.037). After treatment of PAR-2 AP, both mRNA and protein levels for PAR-2, cathelicidin, and VEGF significantly increased in cultured keratinocytes, compared with PAR-2 control peptide treatment. CONCLUSION: PAR-2 may participate in the pathogenesis of rosacea through activation of cathelicidin LL-37, a mediator of innate immune responses in the skin.

Regional Differences in Chronic Stress-induced Alterations in Mast Cell and Protease-activated Receptor-2-positive Cell Numbers in the Colon of Ws/Ws Rats

BACKGROUND/AIMS: There have been no reports on the effect of chronic psychological stress on colonic immune cells or the regional differences. We aimed to investigate the effect of chronic psychological stress on the number of mast cells and protease-activated receptor (PAR)-2-positive cells in the rat colonic mucosa. METHODS: Six-week-old and 14-week-old Ws/Ws rats, which lack mast cells after 10 weeks, were used as control and mast cell-deficient groups, respectively. The rats were divided into stress and sham-treated groups. Rats in the stressed group were exposed to water avoidance stress (WAS, 1 hour/day) for 13 days. Fecal pellet output and the number of mast cells and PAR-2-positive cells in colonic mucosa were compared between the WAS and sham groups. RESULTS: In 6-week-old rats, the WAS group showed a significantly higher number of mast cells compared to the sham group. In 14-week-old rats, mast cells were nearly absent in the colonic mucosa. WAS significantly increased PAR-2-positive cells in 14-week-old rats, but not in 6-week-old rats. Indirect estimation of PAR-2-positive mast cells in 6-week-old rats suggested that the majority of increased mast cells following WAS did not express PAR-2. WAS increased mast cells and PAR-2-positive cells mainly in the proximal colon. Fecal pellet output was continuously higher in the WAS group than in the sham group, and the difference was significant for both 6-week-old and 14-week-old rats. CONCLUSIONS: Chronic psychological stress increased the number of mast cells and PAR-2-positive cells in rat colonic mucosa, and these increases were more prominent in the proximal colon.

Four Possible Itching Pathways Related to the TRPV1 Channel, Histamine, PAR-2 and Serotonin

The following four possible pathways for itching sensation have been suggested by recent reports. 1) Histaminergic TRPV1-positive pathway: Although histamine-positive nerve fibers cannot strictly be classified as “itch specific” due to their excitation also by pure algogens (making them itch-selective), the existence of a subpopulation of nociceptors responsible for itching is strongly suggested. Moreover, the TRPV1-expressing neurons have been suggested to be the main sensors and mediators of itching. 2) Histaminergic TRPV1-negative pathway: The scratching behavior caused by itching was not different between capsaicin-pre-treated and vehicle-treated (control) mast cell-rich NC mice. This result suggests the existence of a capsaicin-insensitive (TRPV1-negative) histaminergic pathway. 3) Non-histaminergic PAR-2 pathway: Protease-activated receptor 2 (PAR-2) has been shown to play a role in the itching of atopic dermatitis (AD). The itch evoked by cowhage (a non-histaminergic pruritogen that activates PAR-2) is very similar in characteristics to the itch evoked by conditions such as AD. 4) Non-histaminergic serotonin (5-HT) pathway: 5-HT alone applied to the human skin evokes an itching sensation and has been suggested to be involved in the itching associated with pruritic diseases, such as polycythemia vera and cholestasis.

The Clinical Assessment of Protease-Activated Receptor-2 Expression in Inflammatory Cells from Peripheral Blood and Bronchoalveolar Lavage Fluid in Idiopathic Pulmonary Fibrosis / 결핵및호흡기질환

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a lethal pulmonary fibrotic disease. In general, the exaggerated activation of the coagulation cascade has been observed during initiation or maintenance of the fibrotic disease. In our recent study, immunohistochemical expression of protease-activated receptor-2 (PAR-2), which plays a key role in coagulation cascade, was observed in surgical specimen of IPF patients, and associated with poor clinical outcome. The aim of this study was to evaluate the overexpression of PAR-2 in inflammatory cells from peripheral blood and bronchoalveolar lavage fluid in IPF patients. METHODS: From May 2011 to March 2012, IPF patients and controls were enrolled in Seoul National University Hospital. Peripheral blood and bronchoalveolar lavage fluid were collected for analysis of PAR-2 expression. Flow cytometry and reverse transcription polymerase chain reaction were used for PAR-2 receptor and mRNA assessment. RESULTS: Twelve IPF patients and 14 controls were included in this study. Among them, flow cytometry analysis was conducted from 26 peripheral blood (patient group, 11; control group, 13) and 7 bronchoalveolar lavage fluid (patient group, 5; control group, 2). The expression of PAR-2 receptor was not different between patient and control groups (p=0.074). Among all 24 population, PAR-2 mRNA assessment was performed in 19 persons (patient group, 10; control group, 9). The mRNA expression of PAR-2 was not significant different (p=0.633). CONCLUSION: In IPF patients, PAR-2 receptor and mRNA expression were not different from control group.

Effects of tacrolimus on the expression of proteinase activated receptor 2 in lesions of atopic dermatitis / 中华皮肤科杂志

Objective To detect the expression of proteinase activated receptor 2 (PAR-2) in the skin of patients with atopic dermatitis (AD) and to evaluate the effects of tacrolimus on the expression.Methods Six patients with acute moderate or severe AD were enrolled in this study and topically treated with tacrolimus 0.1％ ointment twice daily for 3 weeks.Tissue samples were obtained from the lesions and non-lesional skin at least 10 cm away from the lesions before and after the 3-week treatment.Skin specimens from 6 normal human controls served as the control.Patients were evaluated at the baseline,1 and 3 weeks after the beginning of treatment for clinical symptoms and signs by visual analogue scale (VAS),eczema area and severity index (EASI) and investigator's global assessment (IGA).The expression of PAR-2 in tissue specimens were determined by immunohistochemistry.Results PAR-2 was expressed throughout the whole epidermis,especially in the granular layer,hair follicles,sweat glands,endothelial cells and nerve fiber-like structures.Before treatment,the expression level (mean optical density) of PAR-2 in keratinocytes was 4339.6 ± 115.8 in lesional skin of AD patients,significantly higher than that in non-lesional skin (4189.0 t 228.9,t =2.85,P ＜0.05) and in normal skin (3864.0 ± 237.3,t =4.31,P ＜ 0.05).After the 3-week treatment with tacrolimus ointment,the expression level of PAR-2 significant decreased to 3942.4 ± 176.6 in keratinocytes from lesional skin of patients with AD (t =4.55,P ＜ 0.05).The expression level of PAR-2 was positively correlated with VAS score for itch,EASI and IGA score in the patients.Conclusions The expression of PAR-2 is enhanced in keratinocytes of lesions from AD patients,and is positively correlated with itch and lesion severity.Topical tacrolimus may suppress the overexpression of PAR-2 in keratinocytes in lesional skin of AD.

Analysis of protease-activated receptor 2 expression and function in cultured human keratinocytes / 中华皮肤科杂志

Objective To assess the expression pattern of protease-activated receptor 2 (PAR2) in human keratinocytes and to characterize its biological functions in the regulation of skin barrier.Methods Primary human keratinocytes and human N/TERT keratinocytes were used as the subject of this study.The expression and distribution of PAR2 in the keratinocytes were analyzed by using immunoflorescence staining and Western blot.Two different PAR2 agonists,trypsin and a PAR2-activating peptide (AP),as well as a PAR2-antagonistic peptide (H2N-FSLLRY-COOH) and a control peptide were used to induce the activation of PAR2 in the keratinocytes.Then,a fluorescence-based calcium mobilization assay was performed to evaluate the biological function of PAR2.Data were statistically analyzed by one-factor analysis of variance.Results Under normal culture conditions,PAR2 was weakly expressed in keratinocytes,and the expression was unaffected by culture medium composition or culture duration.Calcium mobilization was induced by trypsin of 50-250 nmol/L and the PAR2-activating peptide in a dose-and time-dependent pattern.The maximal activation of PAR2 was observed in keratinocytes treated with the PAR2 agonist HAN-SLIGKV-COOH of 75-250 μmol/L.The PAR2-antagonistic peptide (H2N-FSLLRY-COOH) obviously suppressed the increase in calcium mobilization induced by trypsin,while the control peptide PAR-RAP showed no inductive effect on the PAR2 activation based on the absence of calcium mobilization.The substrate-induced calcium release was complete within 250 seconds,and peaked at 50 seconds after the initial trypsin or PAR-AP stimulation.Moreover,the activation of PAR2 was accompanied by an increase in ERK phosphorylation and elicitation of MAPK signaling pathway in keratinocytes.Conclusions Human keratinocytes positively express PAR2,which can be activated by trypsin and PAR2-activating peptides,and the activation of PAR2 may influence the physiological function of keratinocytes by inducing intracellular calcium release.

Protease-activated receptor-2 expression on dendritic cell of Wegener's granulomatosis patients / 中华风湿病学杂志

Objective The aim of this study was to assess the status of protease-activated receptor-2(PAR-2) expression on the peripheral blood immune cells including dendritic cells(DC) of Wegener's granulo matosis(WG) patients.Methods Flow cytometry was used to analyze the expression of PAR-2 protein on peripheral blood immune cells,DC and DC-like monocytes of healthy controls (HC),inactive,active and different medicine-treated WG patients.Two-tail Mann Whitney non-parametric test was used for statistical analysis.Results There was no difference of PAR-2 expression on PMN,monocytes,lymphocytes and DC between WG patients and HC.However,PAR-2 expression on CD14+CD16+ (t=3.823,P=0.004) and CD64+CD16+ (t=2.652,P=0.024) DC-like monocytes was much higher in WG patients compared with HC.In active WG,expression of PAR-2 was up-regulated on the cell surface of PMN (t=2.690,P=0.013 ),monocytes (t=1.688,P=0.047),lymphocytes(t=1.742,P=0.038),BDCA3+DC(t=2.582,P=0.016),CD11c+DC(t=1.828,P=0.044),CD14+CD16+ (t=3.419,P=0.002)and CD64+CD16+ (t=3.494,P=0.005) DC-like monocytes when compared with inactive WG.PAR-2 expression on these cells was similar between cyclophosphamide (Cyc) and Methotrexate (MTX) treated WG patients.Conclusion PAR-2 expression on immune cells,DC and DC-like monocytes correlates with WG occurrence and development.There is no difference in the effects on PAR-2 expression between various medications.

Stress-induced Alterations in Mast Cell Numbers and Proteinase-activated Receptor-2 Expression of the Colon: Role of Corticotrophin-releasing Factor

This study was performed in order to assess whether acute stress can increase mast cell and enterochromaffin (EC) cell numbers, and proteinase-activated receptor-2 (PAR2) expression in the rat colon. In addition, we aimed to investigate the involvement of corticotrophin-releasing factor in these stress-related alterations. Eighteen adult rats were divided into 3 experimental groups: 1) a saline-pretreated non-stressed group, 2) a saline-pretreated stressed group, and 3) an astressin-pretreated stressed group. The numbers of mast cells, EC cells, and PAR2-positive cells were counted in 6 high power fields. In proximal colonic segments, mast cell numbers of stressed rats tended to be higher than those of non-stressed rats, and their PAR2-positive cell numbers were significantly higher than those of non-stressed rats. In distal colonic segments, mast cell numbers and PAR2-positive cell numbers of stressed rats were significantly higher than those of non-stressed rats. Mast cell and PAR2-positive cell numbers of astressin-pretreated stressed rats were significantly lower than those of saline-pretreated stressed rats. EC cell numbers did not differ among the three experimental groups. Acute stress in rats increases mast cell numbers and mucosal PAR2 expression in the colon. These stress-related alterations seem to be mediated by release of corticotrophin-releasing factor.