Role of histamine H4 receptor in the anti-inflammatory pathway of glucocorticoid-induced leucin zipper (GILZ) in a model of lung fibrosis.

INTRODUCTION: This study investigates the interactions between histaminergic system and glucocorticoid-induced leucin zipper (GILZ) in the inflammatory process and glucocorticoid modulation in lung fibrosis. METHODS: Wild-type (WT) and GILZ Knock-Out (KO) mice were treated with bleomycin (0.05 IU) or saline, delivered by intra-tracheal injection. After surgery, mice received a continuous infusion of JNJ7777120 (JNJ, 2 mg/kg b.wt.) or vehicle for 21 days. Lung function was studied by measuring airway resistance to air insufflation through the analysis of pressure at airway opening (PAO). Lung samples were collected to evaluate the expression of histamine H4R, Anx-A1, and p65-NF-kB, the activity of myeloperoxidase (MPO), and the production of pro-inflammatory cytokines. RESULTS: Airway fibrosis and remodeling were assessed by measuring TGF-ß production and α-SMA deposition. JNJ reduces PAO in WT but not in GILZ KO mice (from 22 ± 1 mm to 15 ± 0.5 and from 24 ± 1.5 to 19 ± 0.5 respectively), MPO activity (from 204 ± 3.13 pmol/mg to 73.88 ± 2.63 in WT and from 221 ± 4.46 pmol/mg to 107 ± 5.54 in GILZ KO), the inflammatory response, TGF-ß production, and α-SMA deposition in comparison to WT and GILZ KO vehicle groups. CONCLUSION: In conclusion, the role of H4R and GILZ in relation to glucocorticoids could pave the way for innovative therapies to counteract pulmonary fibrosis.

Adenosine A3 Receptor (A3AR) Agonist for the Treatment of Bleomycin-Induced Lung Fibrosis in Mice.

Adenosine receptors (ARs) are involved in the suppression and development of inflammatory and fibrotic conditions. Specifically, AR activation promotes differentiation of lung fibroblasts into myofibroblasts, typical of a fibrotic event. Pulmonary fibrosis is a severe disease characterized by inflammation and fibrosis of unknown etiology and lacking an effective treatment. The present investigation explored the action of MRS5980, a new, highly potent and selective A3AR agonist, in an established murine model of lung fibrosis. The effects of either vehicle or MRS5980 were studied in mice following intratracheal bleomycin administration. We evaluated the role of the A3AR agonist on lung stiffness, studying the airway resistance to inflation, oxidative stress (8-OHdG and MDA), inflammation, pro- and anti-inflammatory marker levels (IL-1ß, IL-6, TNF-α, IL-10 and IL-17A) and fibrosis establishment, evaluating transforming growth factor (TGF)-ß expression and α-smooth muscle actin (α-SMA) deposition in lungs. Bleomycin administration increased lung stiffness, TGF-ß levels, α-SMA deposition, and inflammatory and oxidative stress markers. The treatment with MRS5980 attenuated all the analyzed functional, biochemical and histopathological markers in a dose-dependent manner. Our findings support the therapeutic potential of A3AR agonists in lung fibrosis by demonstrating reduced disease progression, as indicated by decreased inflammation, TGF-ß expression and fibrotic remodeling.

Role of Histamine H3 Receptor Antagonists on Intraocular Pressure Reduction in Rabbit Models of Transient Ocular Hypertension and Glaucoma.

Intraocular pressure (IOP) has a tendency to fluctuate throughout the day, reaching its peak in the early morning in healthy subjects or glaucoma patients. Likewise, histamine tone also fluctuates over time, being lower at nighttime. Numerous studies have demonstrated a correlation between short-term IOP fluctuation and glaucoma progression; however, it has not yet been determined whether histamine plays a role in IOP fluctuations. The aim of this research was to establish the distribution of the histamine receptor proteins and respective mRNAs in the eye by western blot, immunohistochemistry and RT-PCR in New Zealand rabbits. Furthermore, we used a transient ocular hypertension (OHT) model induced by injection of 50 µL of 5% hypertonic saline into the vitreous and a stable OHT model (100 µL 0.1% carbomer in the anterior chamber) to address the potential IOP-lowering ability of H3 receptor (H3R) antagonists (ciproxifan, DL76 and GSK189254). IOPs were performed with a Tono-Pen at baseline and 60, 120 and 240 min post treatment after transient OHT induction and, every day for 12 days in the stable OHT model. All histamine receptor subtypes were localized in the rabbit retina and ciliary body/trabecular meshwork. All the treatments lowered IOP in a dose-dependent fashion between 0.3% and 1%. More specifically, the effects were maximal with ciproxifan at 60 min post-dose (IOP60 change = -18.84 ± 4.85 mmHg, at 1%), remained stable until 120 min (IOP120 change = -16.38 ± 3.8 mmHg, at 1%) and decayed thereafter to reach baseline values at 240 min. These effects were highly specific and dependent on histamine release as pre-treatment with imetit (H3R agonist, 1%) or pyrilamine (H1R antagonist, 1%) largely blocked ciproxifan-mediated effects. Color Doppler ultrasound examination was performed to evaluate changes in ophtalmic artery resistivity index (RI) before and after repeated dosing with DL 76, GSK189254, ciproxifan and timolol. Chronic treatments with H3R antagonists and timolol improved the vascular performance of ophthalmic arteries and reduced retinal ganglion cell death. Oxidative stress was also reduced and measured 8-Hydroxy-2'-deoxyguanosine (8OHdG) expression, and by dihidroethydium (DHE) staining. These results demonstrated that the histamine system participates in IOP regulation and that H3R antagonists could represent a future promising therapy for glaucoma. Further studies should be focused on the long-term IOP circadian fluctuations.

Role of TGFBR1 and TGFBR2 genetic variants in Marfan syndrome.

OBJECTIVE: Genetic variants in transforming growth factor beta (TGF-ß) receptors type 1 (TGFBR1) and type 2 (TGFBR2) genes have been associated with different hereditary connective tissue disorders sharing thoracic aortic aneurysm and dissection (TAA/D). Mutations in both TGFBR1/2 genes have been described in patients with TAA/D and Marfan syndrome (MFS), and they are associated consistently with Loeys-Dietz syndrome. The existing literature shows discordant data resulting from mutational screening of TGFBR1/2 genes in patients with MFS. The aim of the study was to investigate the role of TGFBR1/2 genetic variants in determining and/or modulating MFS clinical phenotype. METHODS: We investigated 75 unrelated patients with MFS referred to the Center for Marfan Syndrome and Related Disorders (Careggi University Hospital, Florence) who were subjected to FBN1 and TGFBR1/2 Sanger mutational screening. RESULTS: Forty-seven patients with MFS (63%) carried a pathogenetic FBN1 mutation. No pathogenetic mutations were detected in TGFBR1/2 genes. Ten common polymorphisms were identified in TGFBR2 and 6 in TGFBR1. Their association with cardiovascular manifestations was evaluated. Carriers of the A allele of rs11466512, delA allele of c.383delA or delT allele of c.1256-15del1T polymorphisms had a trend toward or significantly reduced z-scores (median [interquartile range (IQR)], 2.2 [1.13-4.77]; 2.1 [1.72-3.48]; 2.5 [1.85-3.86]) with respect to homozygous patients with wild-type MFS (median [IQR], 4.20 [2.39-7.25]; 3.9 [2.19-7.00]; 3.9 [2.14-6.93]). Carriers of the A allele of the rs2276767 polymorphism showed a trend toward increased z-score (median [IQR], 4.9 [2.14-7.16]) with respect to patients with wild-type MFS (median [IQR], 3.3 [1.75-5.45]). The protective effect of TGFBR1/2 genetic score including all the 4 variants was also evaluated. Patients with MFS with two or more protective alleles included in the score had statistically significant reduced aortic z-scores (median [IQR], 2.20 [1.48-3.37]) with respect to patients with 1 or no protective alleles (median [IQR], 4.20 [2.48-7.12]; P = .007). Patients with severe aortic manifestations (aortic z-score ≥ 2 or aortic surgery) showed a significantly lower prevalence of subjects with two or more protective alleles included in the genetic score (29.7%) than patients with no or milder cardiovascular involvement (63.6%; P = .029). The genetic score protective effect on global aortic manifestations severity (aortic z-score ≥ 2 or aortic surgery) was also observed at the logistic regression analysis adjusted for the presence of FBN1 gene mutations (odds ratio, 0.21; 95% CI, 0.05-0.84; P = .028). CONCLUSIONS: In conclusion, our data reappraise the role of TGFBR1 and TGFBR2 as major genes in patients with MFS, and suggest that TGFBR1/2 genetic variants (in particular when evaluated as a burden by score) might play a role in modulating the severity of cardiovascular manifestation in MFS.

Plasmatic carbonic anhydrase IX as a diagnostic marker for clear cell renal cell carcinoma.

Carbonic anhydrase (CA, EC 4.2.1.1) IX is regarded as a tumour hypoxia marker and CA inhibitors have been proposed as a new class of antitumor agents, with one such agent in Phase II clinical trials. The expression of some CAs, in particular the isoforms CA IX and CA XII, has been correlated with tumour aggressiveness and progression in several cancers. The aim of this study was to evaluate the possibility that CA IX could represent a marker related to clear cell Renal Cell Carcinoma (ccRCC). Bcl-2 and Bax, and the activity of caspase-3, evaluated in tissue biopsies from patients, were congruent with resistance to apoptosis in ccRCCs with respect to healthy controls, respectively. In the same samples, the CA IX and pro-angiogenic factor VEGF expressions revealed that both these hypoxia responsive proteins were strongly increased in ccRCC with respect to controls. CA IX plasma concentration and CA activity were assessed in healthy volunteers and patients with benign kidney tumours and ccRCCs. CA IX expression levels were found strongly increased only in plasma from ccRCC subjects, whereas, CA activity was found similarly increased both in plasma from ccRCC and benign tumour patients, compared to healthy volunteers. These results show that the plasmatic level of CA IX, but not the CA total activity, can be considered a diagnostic marker of ccRCCs. Furthermore, as many reports exist relating CA IX inhibition to a better outcome to anticancer therapy in ccRCC, plasma levels of CA IX could be also predictive for response to therapy.

HYDAMTIQ, a selective PARP-1 inhibitor, improves bleomycin-induced lung fibrosis by dampening the TGF-ß/SMAD signalling pathway.

Idiopathic pulmonary fibrosis is a severe disease characterized by excessive myofibroblast proliferation, extracellular matrix and fibrils deposition, remodelling of lung parenchyma and pulmonary insufficiency. Drugs able to reduce disease progression are available, but therapeutic results are unsatisfactory; new and safe treatments are urgently needed. Poly(ADP-ribose) polymerases-1 (PARP-1) is an abundant nuclear enzyme involved in key biological processes: DNA repair, gene expression control, and cell survival or death. In liver and heart, PARP-1 activity facilitates oxidative damage, collagen deposition and fibrosis development. In this study, we investigated the effects of HYDAMTIQ, a potent PARP-1 inhibitor, in a murine model of lung fibrosis. We evaluated the role of PARP on transforming growth factor-ß (TGF-ß) expression and TGF-ß/SMAD signalling pathway in lungs. Mice were intratracheally injected with bleomycin and then treated with either vehicle or different doses of HYDAMTIQ for 21 days. Airway resistance to inflation and lung static compliance, markers of lung stiffness, were assayed. Histochemical and biochemical parameters to evaluate TGF-ß/SMAD signalling pathway with alpha-smooth muscle actin (αSMA) deposition and the levels of a number of inflammatory markers (tumour necrosis factor-α, interleukin-1ß, iNOS and COX-2) were performed. Bleomycin administration increased lung stiffness. It also increased lung PARP activity, TGF-ß levels, pSMAD3 expression, αSMA deposition and content of inflammatory markers. HYDAMTIQ attenuated all the above-mentioned physiological, biochemical and histopathological markers. Our findings support the proposal that PARP inhibitors could have a therapeutic potential in reducing the progression of signs and symptoms of the disease by decreasing TGF-ß expression and the TGF-ß/SMAD transduction pathway.

1,3-Oxazole-based selective picomolar inhibitors of cytosolic human carbonic anhydrase II alleviate ocular hypertension in rabbits: Potency is supported by X-ray crystallography of two leads.

Two lead 1,3-oxazole-based carbonic anhydrase inhibitors (CAIs) earlier identified as selective, picomolar inhibitors of hCA II (a cytosolic target for treatment of glaucoma) have been investigated further. Firstly, they were found to be conveniently synthesized on multigram scale, which enables further development. These compounds were found to be comparable in efficacy to dorzolamide eye drops when applied in the eye drop form as well. Finally, the reasons for unusually high potency of these compounds became understood from their high-resolution X-ray crystallography structures. These data significantly expand our understanding of heterocycle-based primary sulfonamides, many of which have recently emerged from our labs - particularly, from the corneal permeability standpoint.

Protection from Cigarette Smoke-Induced Lung Dysfunction and Damage by H2 Relaxin (Serelaxin).

Cigarette smoke (CS) is the major etiologic factor of chronic obstructive pulmonary disease (COPD), which is characterized by airway remodeling, lung inflammation and fibrosis, emphysema, and respiratory failure. The current therapies can improve COPD management but cannot arrest its progression and reduce mortality. Hence, there is a major interest in identifying molecules susceptible of development into new drugs to prevent or reduce CS-induced lung injury. Serelaxin (RLX), or recombinant human relaxin-2, is a promising candidate because of its anti-inflammatory and antifibrotic properties highlighted in lung disease models. Here, we used a guinea pig model of CS-induced lung inflammation, and remodeling reproducing some of the hallmarks of COPD. Animals exposed chronically to CS (8 weeks) were treated with vehicle or RLX, delivered by osmotic pumps (1 or 10 µg/day) or aerosol (10 µg/ml/day) during CS treatment. Controls were nonsmoking animals. RLX maintained airway compliance to a control-like pattern, likely because of its capability to counteract lung inflammation and bronchial remodeling. In fact, treatment of CS-exposed animals with RLX reduced the inflammatory recruitment of leukocytes, accompanied by a significant reduction of the release of proinflammatory cytokines (tumor necrosis factor α and interleukin-1ß). Moreover, RLX was able to counteract the adverse bronchial remodeling and emphysema induced by CS exposure by reducing goblet cell hyperplasia, smooth muscle thickening, and fibrosis. Of note, RLX delivered by aerosol has shown a comparable efficacy to systemic administration in reducing CS-induced lung dysfunction and damage. In conclusion, RLX emerges as a new molecule to counteract CS-induced inflammatory lung diseases.

Role of histamine H4 receptor ligands in bleomycin-induced pulmonary fibrosis.

Fibrosis of lung tissue is a disease where a chronic inflammatory process determines a pathological remodelling of lung parenchyma. The animal model obtained by intra-tracheal administration of bleomycin in C57BL/6 mice is one of the most validated murine model. Bleomycin stimulates oxidative stress and the production of pro-inflammatory mediators. Histamine H4R have recently been implicated in inflammation and immune diseases. This study was focused to investigate the effects of H4R ligands in the modulation of inflammation and in the reduction of lung fibrosis in C57BL/6 mice treated with bleomycin. C57BL/6 mice were treated with vehicle, JNJ7777120 (JNJ, selective H4R antagonist) or ST-1006 (partial H4R agonist), ST-994 (H4R neutral antagonist) and ST-1012 (inverse H4R agonist) at equimolar doses, released by micro-osmotic pumps for 21days. Airway resistance to inflation was assayed and lung samples were processed to measure malondialdehyde (TBARS); 8-hydroxy-2'-deoxyguanosine (8OHdG); myeloperoxidase (MPO); COX-2 expression and activity as markers of oxidative stress and inflammation. Fibrosis and airway remodelling were evaluated throughout transforming growth factor-ß (TGF-ß), percentage of positive Goblet cells, smooth muscle layer thickness determination. Our results indicated that JNJ, ST-994 and ST-1012 decreased inflammation and oxidative stress markers, i.e. the number of infiltrating leukocytes evaluated as lung tissue MPO, COX-2 expression and activity, TBARS and 8OHdG production. They also reduced the level of TGF-ß, a pro-fibrotic cytokine, collagen deposition, thickness of smooth muscle layer, Goblet cells hyperplasia; resulting in a decrease of airway functional impairment. The results here reported clearly demonstrated that H4R ligands have a beneficial effect in a model of lung fibrosis in the mouse, thus indicating that H4R antagonists or inverse agonists could be a novel therapeutic strategy for lung inflammatory diseases.

Poly(ADP-ribose) polymerase inhibition with HYDAMTIQ reduces allergen-induced asthma-like reaction, bronchial hyper-reactivity and airway remodelling.

Activation of poly(ADP-ribose) polymerases (PARPs) is considered a key event in the molecular and cellular processes leading from acute asthma attacks to bronchial hyper-reactivity, leucocyte recruitment, chronic inflammation, airway remodelling and lung damage. The present investigation has been carried out to investigate the action of hydroxyl-dimethylaminomethyl-thieno[2,3-c]isoquinolin-5(4H)-one (HYDAMTIQ), a new potent PARP inhibitor, in the process leading from asthma-like events to airway damage. Ovalbumin-sensitized guinea pigs exposed two times to allergen inhalation were treated for 8 days with vehicle or HYDAMTIQ. Asthma-like signs, bronchial hyper-reactivity to methacholine, cytokine production, histamine release from mast cells, airway remodelling, collagen deposition and lung damage were evaluated. Repeated HYDAMTIQ administration (1-10 mg/kg/day i.p.) reduced lung PARP activity, delayed the appearance and reduced the severity of allergen-induced cough and dyspnoea and dampened the increased bronchial responses to methacholine. HYDAMTIQ-treated animals presented reduced bronchial or alveolar abnormalities, lower number of eosinophils and other leucocytes in the lung and decreased smooth muscle or goblet cell hyperplasia. The treatment also reduced lung oxidative stress markers, such as malondialdehyde or 8-hydroxy-2'-deoxyguanosine and the lung content of pro-inflammatory cytokines (TNF-α, interleukin (IL)-1ß, IL-5, IL-6 and IL-18). Finally, mast cells isolated from the peritoneal or pleural cavities of sensitized, HYDAMTIQ-treated animals had a reduced ability to release histamine when exposed to ovalbumin in vitro. Our findings support the proposal that PARP inhibitors could have a therapeutic potential to reduce chronic lung inflammation, airway damage and remodelling in severe unresponsive asthmatic patients.

Prevention of bleomycin-induced lung inflammation and fibrosis in mice by naproxen and JNJ7777120 treatment.

Pulmonary fibrosis, a progressive and lethal lung disease characterized by inflammation and accumulation of extracellular matrix components, is a major therapeutic challenge for which new therapeutic strategies are warranted. Cyclooxygenase (COX) inhibitors have been previously utilized to reduce inflammation. Histamine H4 receptor (H4R), largely expressed in hematopoietic cells, has been identified as a novel target for inflammatory and immune disorders. The aim of this study was to evaluate the effect of JNJ7777120 (1-[(5-chloro-1H-indol-2-yl)carbonyl]-4-methylpiperazine), a selective H4R antagonist, and naproxen, a well known nonsteroidal anti-inflammatory drug, and their combination in a murine model of bleomycin-induced fibrosis. Bleomycin (0.05 IU) was instilled intratracheally to C57BL/6 mice, which were then treated by micro-osmotic pump with vehicle, JNJ7777120 (40 mg/kg b.wt.), naproxen (21 mg/kg b.wt.), or a combination of both. Airway resistance to inflation, an index of lung stiffness, was assessed, and lung specimens were processed for inflammation, oxidative stress, and fibrosis markers. Both drugs alone were able to reduce the airway resistance to inflation induced by bleomycin and the inflammatory response by decreasing COX-2 and myeloperoxidase expression and activity and thiobarbituric acid-reactive substance and 8-hydroxy-2'-deoxyguanosine production. Lung fibrosis was inhibited, as demonstrated by the reduction of tissue levels of transforming growth factor-ß, collagen deposition, relative goblet cell number, and smooth muscle layer thickness. Our results demonstrate that both JNJ7777120 and naproxen exert an anti-inflammatory and antifibrotic effect that is increased by their combination, which could be an effective therapeutic strategy in the treatment of pulmonary fibrosis.

Cyclooxygenase-2 and inflammation mediators have a crucial role in reflux-related esophageal histological changes and Barrett's esophagus.

BACKGROUND: Gastroesophageal reflux (GER) causes injury of the esophageal squamous epithelium, a condition called reflux esophagitis. The sequence reflux-esophagitis-intestinal metaplasia-dysplasia-invasive cancer is widely accepted as the main adenocarcinogenetic pathway in the esophagus; however, the mechanisms of this progression need to be better defined. AIMS: We evaluated COX-2 expression and activity in biopsies from patients affected with GER, and these parameters have been correlated with the stage of the disease, ceramide expression, apoptotic process, and angiogenesis. The effects of celecoxib on bile acid- and EGF-induced mucosal proliferation, apoptosis and angiogenesis have been also investigated. METHODS: Four groups of patients were distinguished: non esophagitis, non erosive esophagitis, erosive esophagitis, and Barrett's esophagus. COX-2 expression, basal PGE2 levels, proliferative activity, VEGF expression and apoptosis were evaluated in esophageal biopsies. RESULTS: COX-2 expression, basal PGE2 levels, proliferative activity, VEGF expression and apoptosis progressively increase from non esophagitis patients to patients with non erosive and erosive esophagitis, to those with BE. Incubation of the cells with DCA/EGF increases PGE2 production, proliferative activity and VEGF production, effects prevented by celecoxib pretreatment. Ceramide expression increased from non esophagitis patients to patients with non erosive and erosive esophagitis, and decreased in BE; caspase-3 activity progressively decreased from non esophagitis to BE patients, suggesting an impairment of the apoptotic process with disease progression. CONCLUSION: These results stand for a close relationship between progression of initial steps of gastroesophageal reflux disease (GERD) and COX-2, proliferative activity and EGF/VEGF expression and could have implications in GERD treatment in order to prevent its neoplastic evolution.

Novel Carbonic Anhydrase Inhibitors with Dual-Tail Core Sulfonamide Show Potent and Lasting Effects for Glaucoma Therapy.

Glaucoma, a leading cause of irreversible vision loss worldwide, is characterized by elevated intraocular pressure (IOP), a well-established risk factor across all its forms. We present the design and synthesis of 39 novel carbonic anhydrase inhibitors by a dual-tailed approach, strategically crafted to interact with distinct hydrophobic and hydrophilic pockets of CA active sites. The series was investigated against the CA isoforms implicated in glaucoma (hCA II, hCA IV, and hCA XII), and the X-ray crystal structures of compounds 25a, 25f, and 26a with CA II, along with 14b in complex with a hCA XII mimic, were determined. Selected compounds (14a, 25a, and 26a) underwent evaluation for their ability to reduce IOP in rabbits with ocular hypertension. Derivative 26a showed significant potency and sustained IOP-lowering effects, surpassing the efficacy of the drugs dorzolamide and bimatoprost. This positions compound 26a as a promising candidate for the development of a novel anti-glaucoma medication.

A high-affinity, cis-on photoswitchable beta blocker to optically control ß2-adrenergic receptors in vitro and in vivo.

This study introduces (S)-Opto-prop-2, a second-generation photoswitchable ligand designed for precise modulation of ß2-adrenoceptor (ß2AR). Synthesised by incorporating an azobenzene moiety with propranolol, (S)-Opto-prop-2 exhibited a high PSScis (photostationary state for cis isomer) percentage (∼90 %) and a favourable half-life (>10 days), facilitating diverse bioassay measurements. In vitro, the cis-isomer displayed substantially higher ß2AR binding affinity than the trans-isomer (1000-fold), making (S)-Opto-prop-2 one of the best photoswitchable GPCR (G protein-coupled receptor) ligands reported so far. Molecular docking of (S)-Opto-prop-2 in the X-ray structure of propranolol-bound ß2AR followed by site-directed mutagenesis studies, identified D1133.32, N3127.39 and F2896.51 as crucial residues that contribute to ligand-receptor interactions at the molecular level. In vivo efficacy was assessed using a rabbit ocular hypertension model, revealing that the cis isomer mimicked propranolol's effects in reducing intraocular pressure, while the trans isomer was inactive. Dynamic optical modulation of ß2AR by (S)-Opto-prop-2 was demonstrated in two different cAMP bioassays and using live-cell confocal imaging, indicating reversible and dynamic control of ß2AR activity using the new photopharmacology tool. In conclusion, (S)-Opto-prop-2 emerges as a promising photoswitchable ligand for precise and reversible ß2AR modulation with light. The new tool shows superior cis-on binding affinity, one of the largest reported differences in affinity (1000-fold) between its two configurations, in vivo efficacy, and dynamic modulation. This study contributes valuable insights into the evolving field of photopharmacology, offering a potential avenue for targeted therapy in ß2AR-associated pathologies.

NCX 470 Exerts Retinal Cell Protection and Enhances Ophthalmic Artery Blood Flow After Ischemia/Reperfusion Injury of Optic Nerve Head and Retina.

Purpose: The purpose of this study was to assess the retinal protective activity and ocular hemodynamics after NCX 470 (0.1%) compared to bimatoprost administered as the US Food and Drug Administration (FDA)-approved drug (Lumigan - 0.01% ophthalmic solution, LUM) and at an equimolar dose (0.072%, BIM) to that released by NCX 470. Methods: Endothelin-1 (ET-1) induced ischemia/reperfusion injury model in rabbits was used. ET-1 was injected nearby the optic nerve head (ONH) twice/week for 6 weeks. Starting on week 3, the animals received vehicle (VEH), NCX 470, LUM, or BIM (30 µL/eye, twice daily, 6 days/week) until the end of ET-1 treatment. Intraocular pressure (IOP), ophthalmic artery resistive index (OA-RI), and electroretinogram (ERG) data were collected prior to dosing and at different time points postdosing. Reduced glutathione, 8-Hydroxy 2-deoxyguanosine, and Caspase-3 were determined in the retina of treated eyes. DNA fragmentation was determined by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) staining. Results: ET-1 increased IOP (VEHIOP_Baseline = 20.5 ± 0.8 and VEHIOP_Week6 = 24.8 ± 0.3 mmHg) and OA-RI (VEHOA-RI_Baseline = 0.36 ± 0.02 and VEHOA-RI_Week6 = 0.55 ± 0.01) and reduced rod/cone responses over time. Oxidative stress, inflammation, and apoptotic markers increased in ET-1-treated eyes. NCX 470 prevented IOP (NCX 470IOP_Week6 = 18.1 ± 0.6 mmHg) and OA-RI changes (NCX 470OA-RI_Week6 = 0.33 ± 0.01) and restored ERG amplitude leaving unaltered the respective latency; these effects were only partially demonstrated by LUM or BIM. Additionally, NCX 470 reduced oxidative stress, inflammation, and apoptosis in the retinas of treated eyes. BIM and LUM were numerically less effective on these parameters. Conclusions: NCX 470 repeated ocular dosing ameliorates ocular hemodynamics and retinal cell dysfunction caused by ischemia/reperfusion via nitric oxide- and bimatoprost-mediated mechanisms. Translational Relevance: If confirmed in clinical setting our data may open new therapeutic opportunities to reduce visual field loss in glaucoma.

New Insight in Histamine Functions.

The first properties of histamine (HA) that were elucidated were vasodilation and contraction of smooth muscles in the gut after stimulating gastric acid secretion and constriction of the bronchial area during anaphylaxis [...].

NCX 470 Restores Ocular Hemodynamics and Retinal Cell Physiology After ET-1-Induced Ischemia/Reperfusion Injury of Optic Nerve and Retina in Rabbits.

Purpose: Determine whether NCX 470, a nitric oxide (NO)-donating bimatoprost with clinically demonstrated intraocular pressure (IOP)-lowering effects, improves ocular hemodynamics and retinal physiology. Methods: Endothelin-1 (ET-1)-induced ischemia/reperfusion model in New Zealand white rabbits was used. ET-1 was injected next to the optic nerve twice/week (Monday and Thursday) for 6 weeks. Starting on week 3, animals received NCX 470 (0.1% bid, 6 days/week Monday-Saturday) or vehicle until the end of ET-1 treatment. IOP, ophthalmic artery resistive index (OA-RI) and retina physiology (electroretinogram, ERG) were determined before dosing and at different times post-dosing. All measurements were taken on Mondays before the AM daily dosing (36 h treatment-free). Finally, oxidative stress markers were determined in dissected retina and iris/ciliary body of treated eyes. Results: Injection of ET-1 progressively increased IOP (20.7 ± 0.6, 24.9 ± 1.2, and 27.0 ± 0.6 mmHg at baseline, week 2 and 6, respectively) and OA-RI (0.30 ± 0.02, 0.39 ± 0.02, and 0.42 ± 0.03 at baseline, week 2 and 6, respectively) and reduced rods and/or cones response as indicated by changes in ERG amplitudes under different stimulating conditions. NCX 470 re-established baseline IOP (21.8 ± 1.0 mmHg), OA-RI (0.33 ± 0.02), and ERG amplitude by week 6 (mostly rod response, 0.01Dark_AVeh_6week = 32.2 ± 3.0 µV and 0.01Dark_ANCX470_6week 44.3 ± 4.5 µV; mostly cone response, 3.0Dark_AVeh_6week = 87.6 ± 10.1 µV and 3.0Dark_ANCX470_6week = 122.8 ± 11.4 µV; combined rod/cone response, 3.0Light_AVeh_6week = 49.8 ± 6.5 µV and 3.0Light_ANCX470_6week = 64.2 ± 6.8 µV). NCX 470 also reversed ET-1-induced changes in glutathione and manganese superoxide dismutase (oxidative stress markers) in retina and iris/ciliary body. Conclusions: Repeated ocular topical dosing with NCX 470 reverses ET-1-induced changes in IOP, OA-RI, and ERG suggesting improved ocular hemodynamics and retinal physiology likely independently from its demonstrated IOP-lowering effect.

One-Pot Procedure for the Synthesis of Asymmetric Substituted Ureido Benzene Sulfonamides as Effective Inhibitors of Carbonic Anhydrase Enzymes.

We report a one-pot procedure for the synthesis of asymmetrical ureido-containing benzenesulfonamides based on in situ generation of the corresponding isocyanatobenezenesulfonamide species, which were trapped with the appropriate amines. A library of new compounds was generated and evaluated in vitro for their inhibition properties against a representative panel of the human (h) metalloenzymes carbonic anhydrases (EC 4.2.1.1), and the best performing compounds on the isozyme II (i.e., 7c, 9c, 11g, and 12c) were screened for their ability to reduce the intraocular pressure in glaucomatous rabbits. In addition, the binding modes of 7c, 11f, and 11g were assessed by means of X-ray crystallography.

2-(2-Hydroxyethyl)piperazine derivatives as potent human carbonic anhydrase inhibitors: Synthesis, enzyme inhibition, computational studies and antiglaucoma activity.

Targeting Carbonic Anhydrases (CAs) represents a strategy to treat several diseases, from glaucoma to cancer. To widen the structure-activity relationships (SARs) of our series of piperazines endowed with potent human carbonic anhydrase (hCA) inhibition, a new series of chiral piperazines carrying a (2-hydroxyethyl) group was prepared. The Zn-binding function, the 4-sulfamoylbenzoyl moiety, was connected to one piperazine N-atom, while the other nitrogen was decorated with alkyl substituents. In analogy to the approach used for the synthesis of the previously reported series, the preparation of the new compounds started with (R)- and (S)-aspartic acid. A partial racemization occurred during the synthesis. In order to overcome this problem, other chemical strategies were investigated. The inhibitory activity of the new polar derivatives against four hCAs isoforms I, II, IV and IX using a stopped flow CO2 hydrase assay was determined. Some compounds showed potency in the nanomolar range and a preference for inhibiting hCA IX.

Novel Insight of Histamine and Its Receptor Ligands in Glaucoma and Retina Neuroprotection.

Glaucoma is a multifactorial neuropathy characterized by increased intraocular pressure (IOP), and it is the second leading cause of blindness worldwide after cataracts. Glaucoma combines a group of optic neuropathies characterized by the progressive degeneration of retinal ganglionic cells (RGCs). Increased IOP and short-term IOP fluctuation are two of the most critical risk factors in glaucoma progression. Histamine is a well-characterized neuromodulator that follows a circadian rhythm, regulates IOP and modulates retinal circuits and vision. This review summarizes findings from animal models on the role of histamine and its receptors in the eye, focusing on the effects of histamine H3 receptor antagonists for the future treatment of glaucomatous patients.