Giuseppe Spaziano

The effects of sulodexide on both clinical and molecular parameters in patients with mixed arterial and venous ulcers of lower limbs

Background Mixed venous and arterial ulcers account for approximately 15%–30% of all venous leg ulcerations. Several studies have shown that matrix metalloproteinases (MMPs) and neutrophil gelatinase-associated lipocalin (NGAL) play a central role in the pathophysiology of venous and arterial diseases. Some studies have shown the efficacy of glycosaminoglycans, such as sulodexide (SDX), in treating patients with leg ulcers. The aim of this study was to evaluate clinical effects of SDX and its correlation with MMPs and NGAL expression in patients with mixed arterial and venous leg ulcers. Methods Patients eligible for this study were of both sexes, older than 20 years, and with a clinical and instrumental diagnosis of mixed ulcer. Results Fifty-three patients of both sexes were enrolled and divided into two groups by means of randomization tables. Group A (treated group) comprised 18 females and ten males (median age: 68.7 years) treated with standard treatment (compression therapy and surgery) + SDX (600 lipoprotein lipase-releasing units/day intramuscularly) for 15 days followed by SDX 250 lipase-releasing units every 12 hours day orally for 6 months as adjunctive treatment. Group B (control group) comprised 17 females and eight males (median age: 64.2 years) treated with standard treatment only (compression therapy and surgery). The type of surgery was chosen according to anatomical level of vein incompetence: superficial venous open surgery and/or subfascial endoscopic perforating surgery. In all enrolled patients, blood samples were collected in order to evaluate the plasma levels of MMPs and NGAL through enzyme-linked immunosorbent assay. These results were compared to another control group (Group C) of healthy individuals. Moreover, biopsies of ulcers were taken to evaluate the tissue expression of MMPs and NGAL through Western blot analysis. Our results revealed that SDX treatment is able to reduce both plasma levels and tissue expression of MMPs improving the clinical conditions in patients with mixed ulcers. Conclusion Inhibition of MMPs could represent a possible therapeutic intervention to limit the progression of leg ulceration. In particular, our findings demonstrate the efficacy of SDX in patients with mixed arterial and venous chronic ulcers of the lower limbs.

Novel series of benzoquinones with high potency against 5-lipoxygenase in human polymorphonuclear leukocytes

5-Lipoxygenase (5-LO) is a potential target for pharmacological intervention with various inflammatory and allergic diseases. Starting from the natural dual 5-LO/microsomal prostaglandin E2 synthase (mPGES)-1 inhibitor embelin (2,5-dihydroxy-3-undecyl-1,4-benzoquinone, 2) that suppresses 5-LO activity in human primary leukocytes with IC50 = 0.8-2 μM, we synthesized 48 systematically modified derivatives of 2. We modified the 1,4-quinone to 1,2-quinone, mono- or bimethylated the hydroxyl groups, and varied the C11-n-alkyl residue (C4- to C16-n-alkyl or prenyl) of 2. Biological evaluation yields potent analogues being superior over 2 and obvious structure-activity relationships (SAR) for inhibition of 5-LO. Interestingly, conversion to 1,2-benzoquinone and bimethylation of the hydroxyl moieties strongly improves 5-LO inhibition in polymorphonuclear leukocytes versus 2 up to 60-fold, exemplified by the C12-n-alkyl derivative 22c (4,5-dimethoxy-3-dodecyl-1,2-benzoquinone) with IC50 = 29 nM. Regarding inhibition of mPGES-1, none of the novel benzoquinones could outperform the parental compound 2 (IC50 = 0.21 μM), and only modest suppressive effects on 12- and 15-LOs were evident. Together, our detailed SAR study reveals 22c as highly potent 5-LO-selective lead compound in intact cells that warrants further preclinical evaluation as anti-inflammatory agent.

Nociceptin/orphanin FQ receptor activation decreases the airway hyperresponsiveness induced by allergen in sensitized mice

Several studies suggest that the N/OFQ (nociceptin/orphanin FQ)-NOP (N/OFQ peptide) receptor pathway is involved in airway physiology. We previously demonstrated a modulation of the endogenous N/OFQ levels in allergen-sensitized mice. Here, we investigated the effects of NOP receptor activation in allergen sensitization using a murine model of allergen-induced airway hyperresponsiveness (AHR). BALB/c mice were intraperitoneally treated with the NOP receptor agonist UFP-112, either during the sensitization phase (30 min before ovalbumin administration) or at the end of sensitization process (15 min before bronchopulmonary reactivity evaluation). At day 21 from the first allergen exposure, bronchopulmonary reactivity and total and differential cell count in bronchoalveolar lavage fluid were evaluated. In a separate set of experiments cell proliferation in lymphocytes, cytokine levels, IgE serum levels, and the effect of UFP-112 on IL-13-induced AHR were evaluated. Pretreatment with UFP-112, during the sensitization phase, caused a significant reduction in allergen-induced AHR and total cell lung infiltration. No effect on allergen-induced AHR was observed when the treatment was performed at the end of sensitization process, on tissues harvested from OVA-sensitized mice and on IL-13-induced AHR. The in vitro proliferative response of lymphocytes was significantly reduced by pretreatment during the sensitization phase with UFP-112. This effect was paralleled by a significant modulation of cytokine secretion in pulmonary tissues and lymphocytes. In conclusion, we demonstrated a role for the NOP receptor and N/OFQ pathway in the AHR induced by allergen, probably through a modulation of the immune response that triggers the development of AHR that involves pro- and anti-inflammatory cytokines.

Hydrogen sulfide inhalation ameliorates allergen induced airway hypereactivity by modulating mast cell activation.

Compelling evidence suggests that hydrogen sulfide represents an important gaseous transmitter in the mammalian respiratory system. In the present study, we have evaluated the role of mast cells in hydrogen sulfide-induced effects on airways in a mouse model of asthma. Mice were sensitized to ovalbumin and received aerosol of a hydrogen sulfide donor (NaHS; 100 ppm) starting at day 7 after ovalbumin challenge. Exposure to hydrogen sulfide abrogated ovalbumin-induced bronchial hypereactivity as well as the increase in lung resistance. Concomitantly, hydrogen sulfide prevented mast cell activity as well as FGF-2 and IL-13 upregulation. Conversely, pulmonary inflammation and the increase in plasmatic IgE levels were not affected by hydrogen sulfide. A lack of hydrogen sulfide effects in mast cell deficient mice occurred. Primary fibroblasts harvested from ovalbumin-sensitized mice showed an increased proliferation rate that was inhibited by hydrogen sulfide aerosol. Furthermore, ovalbumin-induced transdifferentiation of pulmonary fibroblasts into myofibroblasts was reversed. Finally, hydrogen sulfide did abrogate in vitro the degranulation of the mast cell-like RBL-2H3 cell line. Similarly to the in vivo experiments the inhibitory effect was present only when the cells were activated by antigen exposure. In conclusion, inhaled hydrogen sulfide improves lung function and inhibits bronchial hyper-reactivity by modulating mast cells and in turn fibroblast activation.

The 5-lipoxygenase inhibitor RF-22c potently suppresses leukotriene biosynthesis in cellulo and blocks bronchoconstriction and inflammation in vivo.

5-Lipoxygenase (5-LO) catalyzes the first two steps in leukotriene (LT) biosynthesis. Because LTs play pivotal roles in allergy and inflammation, 5-LO represents a valuable target for anti-inflammatory drugs. Here, we investigated the molecular mechanism, the pharmacological profile, and the in vivo effectiveness of the novel 1,2-benzoquinone-featured 5-LO inhibitor RF-22c. Compound RF-22c potently inhibited 5-LO product synthesis in neutrophils and monocytes (IC50⩾22nM) and in cell-free assays (IC50⩾140nM) without affecting 12/15-LOs, cyclooxygenase (COX)-1/2, or arachidonic acid release, in a specific and reversible manner, supported by molecular docking data. Antioxidant or iron-chelating properties were not evident for RF-22c and 5-LO-regulatory cofactors like Ca(2+) mobilization, ERK-1/2 activation, and 5-LO nuclear membrane translocation and interaction with 5-LO-activating protein (FLAP) were unaffected. RF-22c (0.1mg/kg; i.p.) impaired (I) bronchoconstriction in ovalbumin-sensitized mice challenged with acetylcholine, (II) exudate formation in carrageenan-induced paw edema, and (III) zymosan-induced leukocyte infiltration in air pouches. Taken together, RF-22c is a highly selective and potent 5-LO inhibitor in intact human leukocytes with pronounced effectiveness in different models of inflammation that warrants further preclinical analysis of this agent as anti-inflammatory drug.

Intratracheal Administration of Mesenchymal Stem Cells Modulates Tachykinin System, Suppresses Airway Remodeling and Reduces Airway Hyperresponsiveness in an Animal Model.

Background The need for new options for chronic lung diseases promotes the research on stem cells for lung repair. Bone marrow-derived mesenchymal stem cells (MSCs) can modulate lung inflammation, but the data on cellular processes involved in early airway remodeling and the potential involvement of neuropeptides are scarce. Objectives To elucidate the mechanisms by which local administration of MSCs interferes with pathophysiological features of airway hyperresponsiveness in an animal model. Methods GFP-tagged mouse MSCs were intratracheally delivered in the ovalbumin mouse model with subsequent functional tests, the analysis of cytokine levels, neuropeptide expression and histological evaluation of MSCs fate and airway pathology. Additionally, MSCs were exposed to pro-inflammatory factors in vitro. Results Functional improvement was observed after MSC administration. Although MSCs did not adopt lung cell phenotypes, cell therapy positively affected airway remodeling reducing the hyperplastic phase of the gain in bronchial smooth muscle mass, decreasing the proliferation of epithelium in which mucus metaplasia was also lowered. Decrease of interleukin-4, interleukin-5, interleukin-13 and increase of interleukin-10 in bronchoalveolar lavage was also observed. Exposed to pro-inflammatory cytokines, MSCs upregulated indoleamine 2,3-dioxygenase. Moreover, asthma-related in vivo upregulation of pro-inflammatory neurokinin 1 and neurokinin 2 receptors was counteracted by MSCs that also determined a partial restoration of VIP, a neuropeptide with anti-inflammatory properties. Conclusion Intratracheally administered MSCs positively modulate airway remodeling, reduce inflammation and improve function, demonstrating their ability to promote tissue homeostasis in the course of experimental allergic asthma. Because of a limited tissue retention, the functional impact of MSCs may be attributed to their immunomodulatory response combined with the interference of neuropeptide system activation and tissue remodeling.

Plasma glutamine decreases immediately after surgery and is related to incisiveness

Glutamine (gln) is the most abundant free amino acid in the blood. It is involved in important metabolic and biochemical processes, like cell proliferation and oxidative stress. Previous studies have demonstrated that gln concentration in human plasma decreases in several conditions such as sepsis, ischemia‐reperfusion, trauma, major surgery and burn. The aim of the present work was to compare the acute effects of different types of surgical interventions and of anesthetization on blood gln concentration. Plasma samples from 88 subjects (30 males and 58 females) were collected before and after major or minor surgery and the gln concentration was analyzed with high‐performance liquid chromatography. The results showed that plasma gln concentration after surgery was lower than pre‐surgery values and that in major surgery the decrease of gln was higher than in minor surgery. No significant effect was shown for sex or type of anesthesia. These results demonstrate the importance of a gln supplementation before a surgical intervention and show that the amount of gln supplementation should also be adjusted based on the type of surgery. J. Cell. Physiol. 227: 1988–1991, 2012.

Exposure to Allergen Causes Changes in NTS Neural Activities after Intratracheal Capsaicin Application, in Endocannabinoid Levels and in the Glia Morphology of NTS

Allergen exposure may induce changes in the brainstem secondary neurons, with neural sensitization of the nucleus solitary tract (NTS), which in turn can be considered one of the causes of the airway hyperresponsiveness, a characteristic feature of asthma. We evaluated neurofunctional, morphological, and biochemical changes in the NTS of naive or sensitized rats. To evaluate the cell firing activity of NTS, in vivo electrophysiological experiments were performed before and after capsaicin challenge in sensitized or naive rats. Immunohistochemical studies, endocannabinoid, and palmitoylethanolamide quantification in the NTS were also performed. This study provides evidence that allergen sensitization in the NTS induced: (1) increase in the neural firing response to intratracheal capsaicin application, (2) increase of endocannabinoid anandamide and palmitoylethanolamide, a reduction of 2-arachidonoylglycerol levels in the NTS, (3) glial cell activation, and (4) prevention by a Group III metabotropic glutamate receptor activation of neural firing response to intratracheal application of capsaicin in both naïve and sensitized rats. Therefore, normalization of ovalbumin-induced NTS neural sensitization could open up the prospect of new treatments based on the recovery of specific brain nuclei function and for extensive studies on acute or long-term efficacy of selective mGlu ligand, in models of bronchial hyperreactivity.

Theophylline action on primary human bronchial epithelial cells under proinflammatory stimuli and steroidal drugs: a therapeutic rationale approach

Theophylline is a natural compound present in tea. Because of its property to relax smooth muscle it is used in pharmacology for the treatment of airway diseases (ie, chronic obstructive pulmonary disease, asthma). However, this effect on smooth muscle is dose dependent and it is related to the development of side effects. Recently, an increasing body of evidence suggests that theophylline, at low concentrations, also has anti-inflammatory effects related to the activation of histone deacetylases. In this study, we evaluated the effects of theophylline alone and in combination with corticosteroids on human bronchial epithelial cells under inflammatory stimuli. Theophylline administrated alone was not able to reduce growth-stimulating signaling via extracellular signal-regulated kinases activation and matrix metalloproteases release, whereas it strongly counteracts this biochemical behavior when administered in the presence of corticosteroids. These data provide scientific evidence for supporting the rationale for the pharmacological use of theophylline and corticosteroid combined drug.

Role of adiponectin in sphingosine-1-phosphate induced airway hyperresponsiveness and inflammation.

Epidemiological data suggest that obesity represent an important risk factor for asthma, but the link between excess fat and airway hyperresponsiveness (AHR) and inflammation is not fully understood. Recently, a key role in physiopathologic conditions of lungs has been given to adiponectin (Acrp30). Acrp30 is one of the most expressed adipokines produced and secreted by adipose tissue, showing an intriguing relationship with metabolism of sphingolipids. Sphingosine-1-phosphate (S1P) has been proposed as an important inflammatory mediator implicated in the pathogenesis of airway inflammation and asthma. In the present study we analyze the effects of recombinant Acrp30 administration in an experimental model of S1P-induced AHR and inflammation. The results show that S1P is able to reduce endogenous Acrp30 serum levels and that recombinant Acrp30 treatment significantly reduce S1P-induced AHR and inflammation. Moreover, we observed a reduction of Adiponectin receptors (AdipoR1, AdipoR2 and T-cadherin) expression in S1P treated mice. Treatment with recombinant Acrp30 was able to restore Acrp30 serum levels and adiponectin receptors expression. These results could indicate the ability of S1P to modulate the Acrp30 action, by modulating not only the serum levels of the protein, but also its receptors. Taken together, these data suggest that adiponectin could represent a possible biomarker in obesity-associated asthma.