Profil glucido-lipidique et risque cardiovasculaire chez les diabétiques de type 2 / Carbohydrate and lipid profile associated with cardiovascular risk in type 2 diabetics

Introduction-Le diabète est un véritable problème de santé publique du fait de ses nombreuses complications potentielles, notamment cardiovasculaires. Notre objectif était de décrire le profil clinico-biologique chez une population de diabé tique type 2 et d'étudier la relation entre l'équilibre glycémique et les anomalies lipidiques avec les complications micro et macroangiopathiques. Matériels et méthodes -Nous avons mené une étude rétrospective portant sur 341 pa tients diabétiques type 2.Les données ont été analysées par le logiciel IBM® SPSS statis tics 20.0. Seules, les associations significatives (p ≤ 5%) étaient retenues. Résultats - quatre-vingt deux pourcent et demi des patients ont un taux d'HbA1c ≥7 %. Plus de 60 % ont une dyslipidémie. Cinquante deux pourcent des patients ont un taux du LDLc ≤ 1 g/l, et 64,4 % ont un taux du Non-HDLc >1g/l. Environ 66 % des patients ont une hypertension artérielle. quarante pourcent des patients ont présenté une macroangio pathie et 66,8 % une microangiopathie (p=0,0001). L'analyse par régression logistique, a montré que l'HbA1c est le paramètre biologique le plus associé aux complications macroangiopathiques (p=0,008), alors que pour les complications micro-angiopathiques, l'HTA était le seul facteur associé (p = 0,03). Pour la cardiopathie ischémique, la dyslipi démie et l'HTA étaient les facteurs les plus associés. Conclusion -Notre étude a montré une fréquence élevée des complications micro et macroangiopathiques et des anomalies lipidiques, ainsi qu'un très mauvais équilibre glycémique. L'HbA1c, la dyslipidémie et l'HTA sont les facteurs les plus associés au risque cardiovasculaire.

Background-Diabetes is a real health public problem because of its many potential complications, particularly the cardiovascular ones.The aim of this work was to describe the clinical and biological profile in type 2 diabetic population, then to study the relationship between glycemic control and lipid abnormalities with micro and macro vascular complications. Methods - It was about a retrospective study of 341 type 2 diabetes patients' with an average age of 60.1 ± 11.71 years.The IBM® SPSS statistics 20.0 software was used for analyzing data. Only significant associations (p ≤ 5%) were retained. Results -An HbA1c level ≥7% was observed in 82,5% of patients, More than 60% have dyslipidemia. 52,8% of them have an LDLc level ≤ 1 g/l, and 64,4% have a Non-HDLc level >1g/l. Sixty-six percent of patients have high blood pressure. The macrovascular disorders were observed on 30,9% of patients and microvascular ones on 66,8% of them (p = 0.0001).The logistic regression analysis showed that HbA1c was the most significant biological parameter (p=0,008). while for micro-vascular complications, high blood pressure was the only associated factor (p = 0.03). For ischemic heart disease, dyslipidemia and high blood pressure were the most associated factors. Conclusion - this study showed a high frequency of micro and macrovascular complications, lipid abnormalities and a very poor glycemic control. The elevation of HbA1c level, the high blood pressure and dyslipidemia are the most associated factors with a high cardiovascular risk.

Pharmacological blockade of protease-Activated Receptor 2 improves airway remodeling and lung inflammation in experimental allergic asthma

Abstract Protease-activated receptors (PARs) are metabotropic G-protein-coupled receptors that are activated via proteolytic cleavage of a specific sequence of amino acids in their N-terminal region. PAR2 has been implicated in mediating allergic airway inflammation. This study aims to study the effect of PAR2 antagonist ENMD1068in lung inflammation and airway remodeling in experimental asthma. Allergic lung inflammation was induced in sensitized BALB/c mice through intranasal instillations of ovalbumin (OVA), and mice were pretreated with ENMD1068 1 hour before each OVA challenge. Bronchoalveolar lavage fluid (BALF) was collected, and the lungs were removed at different time intervals after OVA challenge to analyze inflammation, airway remodeling and airway hyperresponsiveness. Ovalbumin promoted leukocyte infiltration into BALF in a PAR2-dependent manner. ENMD1068 impaired eosinophil peroxidase (EPO) and myeloperoxidase (MPO) activity in the lung parenchyma into BALF and reduced the loss of dynamic pulmonary compliance, lung resistance in response to methacholine, mucus production, collagen deposition and chemokine (C-C motif) ligand 5 expression compared to those in OVA-challenged mice. We propose that proteases released after an allergen challenge may be crucial to the development of allergic asthma in mice, and PAR2 blockade may be useful as a new pharmacological approach for the treatment of airway allergic diseases.

Characterization of the distinct mechanism of agonist-induced canine platelet activation

Platelet activation has a major role in hemostasis and thrombosis. Various agonists including adenosine diphosphate (ADP) and thrombin interact with G protein-coupled receptors (GPCRs) which transduce signals through various G proteins. Recent studies have elucidated the role of GPCRs and their corresponding G proteins in the regulation of events involved in platelet activation. However, agonist-induced platelet activation in companion animals has not been elucidated. This study was designed to characterize the platelet response to various agonists in dog platelets. We found that 2-methylthio-ADP-induced dog platelet aggregation was blocked in the presence of either P2Y₁ receptor antagonist MRS2179 or P2Y₁₂ receptor antagonist AR-C69931MX, suggesting that co-activation of both the P2Y₁ and P2Y₁₂ receptors is required for ADP-induced platelet aggregation. Thrombin-induced dog platelet aggregation was inhibited in the presence of either AR-C69931MX or the PKC inhibitor GF109203X, suggesting that thrombin requires secreted ADP to induce platelet aggregation in dog platelets. In addition, thrombin-mediated Akt phosphorylation was inhibited in the presence of GF109203X or AR-C69931MX, indicating that thrombin causes Gi stimulation through the P2Y₁₂ receptor by secreted ADP in dog platelets. Unlike human and murine platelets, protease-activated receptor 4 (PAR4)-activating peptide AYPGKF failed to cause dog platelet aggregation. Moreover, PAR1-activating peptide SFLLRN or co-stimulation of SFLLRN and AYPGKF failed to induce dog platelet aggregation. We conclude that ADP induces platelet aggregation through the P2Y₁ and P2Y₁₂ receptors in dogs. Unlike human and murine platelets, selective activation of the PAR4 receptor may be insufficient to cause platelet aggregation in dog platelets.

Protease-Activated Receptors 2-Antagonist Suppresses Asthma by Inhibiting Reactive Oxygen Species-Thymic Stromal Lymphopoietin Inflammation and Epithelial Tight Junction Degradation

PURPOSE: Protease-activated receptor 2 (PAR2) reportedly triggers the immune response in allergic asthma. We aimed to investigate the mechanism on allergic inflammation mediated by PAR2. METHODS: Human lung epithelial cells (A549 cells) were used for in vitro, and the German cockroach extract (GCE)-induced mouse model was developed for in vivo studies. RESULTS: In A549 cells, the levels of reactive oxygen species (ROS) and thymic stromal lymphopoietin (TSLP) were significantly increased by GCE treatment, but were suppressed by PAR2-antagonist (PAR2-ant) or N-acetylcysteine (NAC) treatment. Claudin-1 was degraded by GCE, and was restored by PAR2-ant or NAC in the cells. In the mouse model, the clinical appearance including bronchial hyperresponsiveness, bronchoalveolar lavage fluid analysis and total immunoglobulin E were significantly suppressed by PAR2-ant or NAC. Moreover, TSLP levels in the lung were suppressed by the same treatments in the lung. Claudin-1 was also degraded by GCE, and was restored by PAR2-ant or NAC. CONCLUSIONS: ROS generation and epidermal tight junction degradation are triggered by protease, followed by the induction of TSLP in allergic asthma. Our findings could suggest that PAR2-ant or anti-oxidants could be considered for allergic diseases as preventive alternatives.

The Role of Visceral Hypersensitivity in Irritable Bowel Syndrome: Pharmacological Targets and Novel Treatments

Irritable bowel syndrome (IBS) is the most common disorder referred to gastroenterologists and is characterized by altered bowel habits, abdominal pain, and bloating. Visceral hypersensitivity (VH) is a multifactorial process that may occur within the peripheral or central nervous systems and plays a principal role in the etiology of IBS symptoms. The pharmacological studies on selective drugs based on targeting specific ligands can provide novel therapies for modulation of persistent visceral hyperalgesia. The current paper reviews the cellular and molecular mechanisms underlying therapeutic targeting for providing future drugs to protect or treat visceroperception and pain sensitization in IBS patients. There are a wide range of mediators and receptors participating in visceral pain perception amongst which substances targeting afferent receptors are attractive sources of novel drugs. Novel therapeutic targets for the management of VH include compounds which alter gut-brain pathways and local neuroimmune pathways. Molecular mediators and receptors participating in pain perception and visceroperception include histamine-1 receptors, serotonin (5-hydrodytryptamine) receptors, transient receptor potential vanilloid type I, tachykinins ligands, opioid receptors, voltage-gated channels, tyrosine receptor kinase receptors, protease-activated receptors, adrenergic system ligands, cannabinoid receptors, sex hormones, and glutamate receptors which are discussed in the current review. Moreover, several plant-derived natural compounds with potential to alleviate VH in IBS have been highlighted. VH has an important role in the pathology and severity of complications in IBS. Therefore, managing VH can remarkably modulate the symptoms of IBS. More preclinical and clinical investigations are needed to provide efficacious and targeted medicines for the management of VH.

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.

Expressions of protease-activated receptors in human gingival fibroblasts and its functions in periodontitis / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the expression types of protease-activated receptors(PAR) in human gingival fibroblasts(HGF) and the functions of PAR in periodontitis.</p><p><b>METHODS</b>Primary HGF were cultured.Reverse transcription PCR(RT-PCR) was used to detect the expression of PAR in HGF. Recombinant gingipain R (rRgp) was applied to HGF. The change of PAR expression on the cell surface was analyzed by real-time quantitative RT-PCR, and enzyme-linked immunosorbent assay (ELISA) was used to detect the change of the interleukin (IL)-6 production from HGF. The results of RT-PCR and ELISA were statistically analyzed using the two independent samples t-test of SPSS10.0 software.</p><p><b>RESULTS</b>HGF expressed PAR-1 and PAR-3. The expression of PAR-1 and PAR-3 changed after two rRgp treatment with HGF cells. The relative expression of PAR-1 was decreased from 1.04 ± 0.31 to 0.67 ± 0.11 and 0.31 ± 0.11. The relative expression of PAR-3 was decreased from 1.01 ± 0.44 to 0.79 ± 0.13 and 0.44 ± 0.12(P < 0.05). The level of IL-6 was increased after rRgp treatment for 8 h. The control group was (18.77 ± 4.09) µg/L, the rRgp treatment groups were (179.36 ± 15.81) and (320.56 ± 26.19) µg/L respectively.</p><p><b>CONCLUSIONS</b>HGF expressed PAR-1 and PAR-3 and were involved in periodontal inflammation.</p>

Diabetic retinopathy: could the alpha-1 antitrypsin be a therapeutic option?

Diabetic retinopathy is one of the most important causes of blindness. The underlying mechanisms of this disease include inflammatory changes and remodeling processes of the extracellular-matrix (ECM) leading to pericyte and vascular endothelial cell damage that affects the retinal circulation. In turn, this causes hypoxia leading to release of vascular endothelial growth factor (VEGF) to induce the angiogenesis process. Alpha-1 antitrypsin (AAT) is the most important circulating inhibitor of serine proteases (SERPIN). Its targets include elastase, plasmin, thrombin, trypsin, chymotrypsin, proteinase 3 (PR-3) and plasminogen activator (PAI). AAT modulates the effect of protease-activated receptors (PARs) during inflammatory responses. Plasma levels of AAT can increase 4-fold during acute inflammation then is so-called acute phase protein (APPs). Individuals with low serum levels of AAT could develop disease in lung, liver and pancreas. AAT is involved in extracellular matrix remodeling and inflammation, particularly migration and chemotaxis of neutrophils. It can also suppress nitric oxide (NO) by nitric oxide sintase (NOS) inhibition. AAT binds their targets in an irreversible way resulting in product degradation. The aim of this review is to focus on the points of contact between multiple factors involved in diabetic retinopathy and AAT resembling pleiotropic effects that might be beneficial.

Inhibition of Fungi-Induced Nasal Polyp Epithelial Cells Activation by Corticosteroids

BACKGROUND AND OBJECTIVES: Airway epithelial cells contribute to the pathogenesis of air disease by their interaction with inhalant pathogenic extracts. Airborne fungi interact with nasal epithelial cell and enhance the production of inflammatory cytokines. Glucocorticosteroids (GCs) have been used therapeutically for nasal polyps and allergic disease with potent anti-inflammatory effects. The purpose of this study was to investigate the inhibitory effect of GCs on fungi induced nasal epithelial cell activation. MATERIALS AND METHODS: The epithelial cells of nasal polyps were obtained from patients and stimulated with Alternaria. To evaluate the anti-inflammatory effects of GCs, Alternaria was pretreated with GCs (triamcinolone, dexamethasone, and budesonide) and cultured with epithelial cells. Interleukin-8 (IL-8) and granulocyte-macrophage colony stimulating factor (GM-CSF) were measured to determine the activation of epithelial cells. Reverse transcriptase-polymerase chain reaction (RT-PCR) test for protease-activated receptors (PARs) mRNA expression in nasal epithelial cells were performed. RESULTS: Alternaria enhanced the production of IL-8 and GM-CSF from nasal epithelial cells. GCs inhibited the activation of nasal epithelial cells, but the PAR2 and PAR3 mRNA expression were not suppressed by GCs. CONCLUSION: These data suggest that GCs inhibit the production of chemical mediators by Alternaria, but anti-inflammatory effect of GCs are not associated with PARs.

Protease-activated receptors and inflammatory hyperalgesia

Recent advances in basic science pointed to a role for proteinases, through the activation of proteinase-activated receptors (PARs) in nociceptive mechanisms. Activation of PAR1, PAR2 and PAR4 either by proteinases or by selective agonists causes inflammation inducing most of the cardinal signs of inflammation: swelling, redness, and pain. Sub-inflammatory doses of PAR2 agonist still induced hyperalgesia and allodynia while PAR2 has been shown to be implicated in the generation of hyperalgesia in different inflammatory models. In contrast, sub-inflammatory doses of PAR1 increases nociceptive threshold, inhibiting inflammatory hyperalgesia, thereby acting as an analgesic agent. PARs are present and functional on sensory neurons, where they participate either directly or indirectly to the transmission and/or inhibition of nociceptive messages. Taken together, the results discussed in this review highlight proteinases as signaling molecules to sensory nerves. We need to consider proteinases and the receptors that are activated by proteinases as important potential targets for the development of analgesic drugs in the treatment of inflammatory pain.

Role of protease-activated receptor-2 in inflammation, and its possible implications as a putative mediator of periodontitis

Proteinase-activated receptor-2 (PAR2) belongs to a novel subfamily of G-protein-coupled receptors with seven-transmembrane domains. This receptor is widely distributed throughout the body and seems to be importantly involved in inflammatory processes. PAR2 can be activated by serine proteases such as trypsin, mast cell tryptase, and bacterial proteases, such as gingipain produced by Porphyromonas gingivalis. This review describes the current stage of knowledge of the possible mechanisms that link PAR2 activation with periodontal disease, and proposes future therapeutic strategies to modulate the host response in the treatment of periodontitis.

Protease from Airborn Fungi Induce Activation of Nasal Epithelial Cells / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The nasal epithelium is the first barrier encountered by airborne allergens and an active participant in airway inflammation. Fungi have been increasingly recognized as important pathogens in sinusitis and consists of several allergenic proteins. We hypothesized that fungi induce the release of inflammatory mediators, and tried to find out the mechanism of epithelial cell activation. SUBJECTS AND METHOD: The epithelial cells of nasal polyp were obtained from patients and stimulated with Alternaria, Aspergillus, and Cladosporium. Interleukin-8 (IL-8), granulocyte-macrophage colony stimulating factor (GM-CSF), regulated on activation and normal T expressed and secreted (RANTES) were measured to determine the activation of epithelial cells. Nasal epithelial cell activation was inhibited with serine and cystein protease inhibitors. Reverse transcriptase-polymerase chain reaction (RT-PCR) test for protease-activated receptors (PARs) mRNA expression in nasal epithelial cells were performed. RESULTS: Fungi enhanced the production of chemical mediators from nasal epithelial cells. Serine protease inhibitors inhibited the activation of nasal epithelial cells. When nasal epithelial cells were activated, PAR2 and PAR3 mRNAs were more strongly expressed than non-activated cells. CONCLUSION: Serine proteases in fungi interact with nasal epithelial cells and enhance the production of inflammatory cytokines. PARs might play a role in the process of epithelial cell activation.