Potential benefit of the cathepsin S inhibitor, ASP1617, as a treatment for systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the dysregulation of various cell types and immunological pathways. Autoantibodies play an important role in its pathogenesis. The presence of autoantibodies suggests that self-antigen presentation through major histocompatibility complex (MHC) class II on antigen presenting cells is involved in the pathogenesis of autoimmune diseases, including SLE. Cathepsin S (CatS) is a key protease for antigen peptide loading onto lysosomal/endosomal MHC class II molecules through invariant chain degradation to promote antigen presentation. Inhibition of CatS is therefore expected to suppress antigen presentation via MHC class II, T and B cell activation, and antibody production from B cells. Here, we report the pharmacological profile of ASP1617, a novel CatS inhibitor. ASP1617 induced invariant chain accumulation and decreased the expression level of MHC class ΙΙ on the cell surface in both mouse and human B cells. Further, ASP1617 prevented DO11.10 mice T cell proliferation to ovalbumin antigen. We investigated the effects of ASP1617 and mycophenolate mofetil (MMF) on the development of lupus-like nephritis in NZB/W F1 mice, a widely used SLE mouse model. Oral administration of ASP1617 suppressed anti-dsDNA IgG, prevented progression of lupus-like glomerulonephritis, and significantly prevented proteinuria excretion. In contrast, MMF did not suppress anti-dsDNA IgG. Further, we found that plasma and/or urine CatS levels were increased in specimens from NZB/W F1 mice and several SLE patients. These results indicate that CatS may be an attractive therapeutic target for the treatment of SLE.

Ulinastatin alleviates early brain injury after intracerebral hemorrhage by inhibiting oxidative stress and neuroinflammation via ROS/MAPK/Nrf2 signaling pathway

Purpose: Spontaneous intracerebral hemorrhage (ICH) is still a major public health problem, with high mortality and disability. Ulinastatin (UTI) was purified from human urine and has been reported to be anti-inflammatory, organ protective, and antioxidative stress. However, the neuroprotection of UTI in ICH has not been confirmed, and the potential mechanism is unclear. In the present study, we aimed to investigate the neuroprotection and potential molecular mechanisms of UTI in ICH-induced early brain injury in a C57BL/6 mouse model. Methods: The neurological score, brain water content, neuroinflammatory cytokine levels, oxidative stress levels, and neuronal damage were evaluated. Results: UTI treatment markedly increased the neurological score, alleviated brain edema, decreased the levels of the inflammatory cytokines tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), IL-6, and NF-κB, decreased the levels of reactive oxygen species (ROS) and malondialdehyde (MDA), and upregulated the levels of glutathione (GSH), superoxide dismutase (SOD), and Nrf2. This finding indicated that UTI-mediated inhibition of neuroinflammation and oxidative stress alleviated neuronal damage after ICH. The neuroprotective capacity of UTI is partly dependent on the ROS/MAPK/Nrf2 signaling pathway. Conclusions: UTI improves neurological outcomes in mice and reduces neuronal death by protecting against neural neuroinflammation and oxidative stress.

Nafamostat mesilate, a nuclear factor kappa B inhibitor, enhances the antitumor action of radiotherapy on gallbladder cancer cells.

Nuclear factor kappa B (NF-κB) is a transcriptional factor that can be activated by radiotherapy and chemotherapy. The synthetic protease inhibitor nafamostat mesilate (NM) inhibits NF-κB activity and exerts antitumor actions in various types of cancer. In the present study, we hypothesized that NM might enhance the antitumor action of radiotherapy on gallbladder cancer (GBC) cells by inhibiting radiation-induced NF-κB activity. Thus, we investigated the correlation between radiotherapy and NF-κB activity in GBC cells. We assessed the in vitro effects of radiotherapy with or without NM on NF-κB activity, apoptosis of GBC cells (NOZ and OCUG-1), induction of apoptotic cascade, cell cycle progression, and viability of GBC cells using four treatment groups: 1) radiation (5 Gy) alone; 2) NM (80 µg/mL and 40 µg/mL, respectively) alone; 3) combination (radiation and NM); and 4) vehicle (control). The same experiments were performed in vivo using a xenograft GBC mouse model. In vitro, NM inhibited radiation-induced NF-κB activity. Combination treatment significantly attenuated cell viability and increased cell apoptosis and G2/M phase cell cycle arrest compared with those in the other groups for NOZ and OCUG-1 cells. Moreover, combination treatment upregulated the expression of apoptotic proteins compared with that after the other treatments. In vivo, NM improved the antitumor action of radiation and increased the population of Ki-67-positive cells. Overall, NM enhanced the antitumor action of radiotherapy on GBC cells by suppressing radiation-induced NF-κB activity. Thus, the combination of radiotherapy and NM may be useful for the treatment of locally advanced unresectable GBC.

Protease inhibitor-based direct-acting antivirals are associated with increased risk of aminotransferase elevations but not hepatic dysfunction or decompensation.

BACKGROUND & AIMS: Cases of acute liver injury (ALI) have been reported among chronic HCV-infected patients receiving protease inhibitor (PI)-based direct-acting antiviral (DAA) regimens, but no analyses have compared the risk of ALI in patients receiving PI- vs. non-PI-based DAAs. Thus, we compared the risk of 3 ALI outcomes between patients (by baseline Fibrosis-4 [FIB-4] group) receiving PI-based or non-PI-based DAAs. METHODS: We conducted a cohort study of 18,498 patients receiving PI-based DAA therapy (paritaprevir/ritonavir/ombitasvir±dasabuvir, elbasvir/grazoprevir, glecaprevir/pibrentasvir) matched 1:1 on propensity score to those receiving non-PI-based DAAs (sofosbuvir/ledipasvir, sofosbuvir/velpatasvir) in the 1945-1965 Veterans Birth Cohort (2014-2019). During exposure to DAA therapy, we determined development of: i) alanine aminotransferase (ALT) >200 U/L, ii) severe hepatic dysfunction (coagulopathy with hyperbilirubinemia), and iii) hepatic decompensation. We used Cox regression to determine hazard ratios (HRs) with 95% CIs for each ALI outcome within groups defined by baseline FIB-4 (≤3.25; >3.25). RESULTS: Among patients with baseline FIB-4 ≤3.25, those receiving PIs had a higher risk of ALT >200 U/L (HR 3.98; 95% CI 2.37-6.68), but not severe hepatic dysfunction (HR 0.67; 95% CI 0.19-2.39) or hepatic decompensation (HR 1.01; 95% CI 0.29-3.49), compared to those receiving non-PI-based regimens. For those with baseline FIB-4 >3.25, those receiving PIs had a higher risk of ALT >200 U/L (HR, 2.15; 95% CI 1.09-4.26), but not severe hepatic dysfunction (HR, 1.23 [0.64-2.38]) or hepatic decompensation (HR, 0.87; 95% CI 0.41-1.87), compared to those receiving non-PI-based regimens CONCLUSION: While risk of incident ALT elevations was increased in those receiving PI-based DAAs in both FIB-4 groups, the risk of severe hepatic dysfunction and hepatic decompensation did not differ between patients receiving PI- or non-PI-based DAAs in either FIB-4 group. LAY SUMMARY: Cases of liver injury have been reported among patients treated with protease inhibitor-based direct-acting antivirals for hepatitis C infection, but it is not clear if the risk of liver injury among people starting these drugs is increased compared to those starting non-protease inhibitor-based therapy. In this study, patients receiving protease inhibitor-based treatment had a higher risk of liver inflammation than those receiving a non-protease inhibitor-based treatment, regardless of the presence of pre-treatment advanced liver fibrosis/cirrhosis. However, the risk of severe liver dysfunction and decompensation were not higher for patients treated with protease inhibitor-based regimens.

Development of potent and selective inhibitors targeting the papain-like protease of SARS-CoV-2.

The COVID-19 pandemic has been disastrous to society and effective drugs are urgently needed. The papain-like protease domain (PLpro) of SARS-CoV-2 (SCoV2) is indispensable for viral replication and represents a putative target for pharmacological intervention. In this work, we describe the development of a potent and selective SCoV2 PLpro inhibitor, 19. The inhibitor not only effectively blocks substrate cleavage and immunosuppressive function imparted by PLpro, but also markedly mitigates SCoV2 replication in human cells, with a submicromolar IC50. We further present a convenient and sensitive activity probe, 7, and complementary assays to readily evaluate SCoV2 PLpro inhibitors in vitro or in cells. In addition, we disclose the co-crystal structure of SCoV2 PLpro in complex with a prototype inhibitor, which illuminates their detailed binding mode. Overall, these findings provide promising leads and important tools for drug discovery aiming to target SCoV2 PLpro.

Epigallocatechin-3-gallate, an active ingredient of Traditional Chinese Medicines, inhibits the 3CLpro activity of SARS-CoV-2.

SARS-CoV-2 is the etiological agent responsible for the ongoing pandemic of coronavirus disease 2019 (COVID-19). The main protease of SARS-CoV-2, 3CLpro, is an attractive target for antiviral inhibitors due to its indispensable role in viral replication and gene expression of viral proteins. The search of compounds that can effectively inhibit the crucial activity of 3CLpro, which results to interference of the virus life cycle, is now widely pursued. Here, we report that epigallocatechin-3-gallate (EGCG), an active ingredient of Chinese herbal medicine (CHM), is a potent inhibitor of 3CLpro with half-maximum inhibitory concentration (IC50) of 0.874 ± 0.005 µM. In the study, we retrospectively analyzed the clinical data of 123 cases of COVID-19 patients, and found three effective Traditional Chinese Medicines (TCM) prescriptions. Multiple strategies were performed to screen potent inhibitors of SARS-CoV-2 3CLpro from the active ingredients of TCMs, including network pharmacology, molecular docking, surface plasmon resonance (SPR) binding assay and fluorescence resonance energy transfer (FRET)-based inhibition assay. The SPR assay showed good interaction between EGCG and 3CLpro with KD ~6.17 µM, suggesting a relatively high affinity of EGCG with SARS-CoV-2 3CLpro. Our results provide critical insights into the mechanism of action of EGCG as a potential therapeutic agent against COVID-19.

Octenidine-based hydrogel shows anti-inflammatory and protease-inhibitory capacities in wounded human skin.

Octenidine dihydrochloride (OCT) is a widely used antiseptic molecule, promoting skin wound healing accompanied with improved scar quality after surgical procedures. However, the mechanisms by which OCT is contributing to tissue regeneration are not yet completely clear. In this study, we have used a superficial wound model by tape stripping of ex vivo human skin. Protein profiles of wounded skin biopsies treated with OCT-containing hydrogel and the released secretome were analyzed using liquid chromatography-mass spectrometry (LC-MS) and enzyme-linked immunosorbent assay (ELISA), respectively. Proteomics analysis of OCT-treated skin wounds revealed significant lower levels of key players in tissue remodeling as well as reepithelization after wounding such as pro-inflammatory cytokines (IL-8, IL-6) and matrix-metalloproteinases (MMP1, MMP2, MMP3, MMP9) when compared to controls. In addition, enzymatic activity of several released MMPs into culture supernatants was significantly lower in OCT-treated samples. Our data give insights on the mode of action based on which OCT positively influences wound healing and identified anti-inflammatory and protease-inhibitory activities of OCT.

Using protease inhibitors to improve protein stability in the presence of skin: A case study on the stability of insulin like growth factor 1.

Insulin-like growth factor 1 (IGF-1) is indicated for growth failure in pediatric patients with primary IGF-1 deficiency and for patients with neutralizing antibodies to growth hormone. IGF-1 was cloned, expressed and purified in-house. Preliminary stability studies prior to the transdermal delivery experiments showed that although stable in contact with stratum corneum, the solution concentration of IGF-1 decreased to 23.63 ± 2.48 and 21.58 ± 2.62% of the initial value upon exposure for 8 h to porcine dermis of 250 and 750 µm thickness. This led to an investigation into how it might be possible to improve the stability of IGF-1 in the presence of porcine/human skin. The stability of IGF-1 in the presence of dermis improved upon heating the skin samples at 60 °C for 2 min suggesting that IGF-1 was subject to enzymatic degradation. Although addition of the protease inhibitor, phenylmethanesulfonyl fluoride (PMSF) alone, did not improve stability, the use of a protease inhibitor cocktail completely blocked proteolytic degradation of IGF-1; the solution concentration after an 8 h exposure to porcine skin was equivalent to the initial level (103.87 ± 9.15%). The results obtained with porcine skin were confirmed with human skin (IGF-1 recovery was 99.31 ± 9.98%). These findings suggest that the inclusion of protease inhibitor cocktails may be useful in limiting the degradation of therapeutic proteins during iontophoresis and transdermal delivery in general - this could be of particular interest for local delivery of peptide/protein therapeutics for dermatological applications.

Evaluation of Sacubitril/Valsartan Initiation in Outpatient Heart Failure Patients.

ABSTRACT: Despite sacubitril/valsartan being on the market since 2015, clinicians are still determining the best way to initiate therapy to optimize outcomes and minimize potential for side effects. The purpose of this study is to investigate real-world outpatient experience of prescribing sacubitril/valsartan therapy based on appropriate patient selection, dosing conversion, and tolerability. This retrospective cohort study evaluated patients' prescribed sacubitril/valsartan therapy in cardiology clinics associated with an academic institution between February 1, 2016, and August 30, 2018. Patients were excluded if they were less than 18 years of age, enrolled in a clinical trial involving sacubitril/valsartan, or had insufficient data. The primary outcome was to determine how many heart failure patients initiated on sacubitril/valsartan were performed so appropriately based on guideline and package insert recommendations. Select secondary outcomes included rates of adverse events and need for adjustment of concomitant heart failure medications. A total of 250 patients were included in this study. For the primary outcome, 125 patients (50%) were appropriately initiated on sacubitril/valsartan. Those who were inappropriately initiated on the medication experienced more symptoms of hypotension (16% in the appropriate start group vs. 28% in the inappropriate start group; P = 0.022) and required more dose decreases of sacubitril/valsartan (6% in the appropriate start group vs. 13% in the inappropriate start group; P = 0.049). In outpatient clinical practice, almost half of patients initiated on sacubitril/valsartan were performed so outside of guideline recommendations, which was associated with an increased risk of hypotension and dose reductions.

Management of disseminated intravascular coagulation associated with aortic aneurysm and vascular malformations.

Aortic aneurysms and vascular malformations are sometimes associated with disseminated intravascular coagulation (DIC). A typical blood coagulation test shows decrease in platelet count and fibrinogen, and increases in fibrin/fibrinogen degradation products (FDP) and D-dimer. The coagulation activation marker thrombin-antithrombin complex (TAT) and the fibrinolysis activation marker plasmin-α2 plasmin inhibitor (PIC) are significantly increased. α2 plasmin inhibitor (α2PI) is significantly reduced. Since no prolongation of prothrombin time (PT) is noticeable and activated partial thromboplastin time (APTT) is shortened in some cases, DIC cannot be diagnosed or ruled out by PT and APTT alone. The cornerstone of treatment for DIC is to treat the underlying disease. However, surgery is not possible in some cases. Follow-up may be appropriate in patients with abnormal results from coagulation tests and no bleeding. However, pharmacotherapy is often required in cases with bleeding. Unfractionated heparin, low molecular weight heparin, protease inhibitors, recombinant thrombomodulin, direct oral anticoagulants, and factor XIII preparations are effective. If PIC is significantly increased and α2PI is significantly decreased, or if the bleeding is severe, tranexamic acid is used as an antifibrinolytic therapy with anticoagulant therapy. In such cases, attention should be paid not only to TAT but also changes in PIC.

Current status of antivirals and druggable targets of SARS CoV-2 and other human pathogenic coronaviruses.

Coronaviridae is a peculiar viral family, with a very large RNA genome and characteristic appearance, endowed with remarkable tendency to transfer from animals to humans. Since the beginning of the 21st century, three highly transmissible and pathogenic coronaviruses have crossed the species barrier and caused deadly pneumonia, inflicting severe outbreaks and causing human health emergencies of inconceivable magnitude. Indeed, in the past two decades, two human coronaviruses emerged causing serious respiratory illness: severe acute respiratory syndrome coronavirus (SARS-CoV-1) and Middle Eastern respiratory syndrome coronavirus (MERS-CoV), causing more than 10,000 cumulative cases, with mortality rates of 10 % for SARS-CoV-1 and 34.4 % for MERS-CoV. More recently, the severe acute respiratory syndrome coronavirus virus 2 (SARS-CoV-2) has emerged in China and has been identified as the etiological agent of the recent COVID-19 pandemic outbreak. It has rapidly spread throughout the world, causing nearly 22 million cases and ∼ 770,000 deaths worldwide, with an estimated mortality rate of ∼3.6 %, hence posing serious challenges for adequate and effective prevention and treatment. Currently, with the exception of the nucleotide analogue prodrug remdesivir, and despite several efforts, there is no known specific, proven, pharmacological treatment capable of efficiently and rapidly inducing viral containment and clearance of SARS-CoV-2 infection as well as no broad-spectrum drug for other human pathogenic coronaviruses. Another confounding factor is the paucity of molecular information regarding the tendency of coronaviruses to acquire drug resistance, a gap that should be filled in order to optimize the efficacy of antiviral drugs. In this light, the present review provides a systematic update on the current knowledge of the marked global efforts towards the development of antiviral strategies aimed at coping with the infection sustained by SARS-CoV-2 and other human pathogenic coronaviruses, displaying drug resistance profiles. The attention has been focused on antiviral drugs mainly targeting viral protease, RNA polymerase and spike glycoprotein, that have been tested in vitro and/or in clinical trials as well as on promising compounds proven to be active against coronaviruses by an in silico drug repurposing approach. In this respect, novel insights on compounds, identified by structure-based virtual screening on the DrugBank database endowed by multi-targeting profile, are also reported. We specifically identified 14 promising compounds characterized by a good in silico binding affinity towards, at least, two of the four studied targets (viral and host proteins). Among which, ceftolozane and NADH showed the best multi-targeting profile, thus potentially reducing the emergence of resistant virus strains. We also focused on potentially novel pharmacological targets for the development of compounds with anti-pan coronavirus activity. Through the analysis of a large set of viral genomic sequences, the current review provides a comprehensive and specific map of conserved regions across human coronavirus proteins which are essential for virus replication and thus with no or very limited tendency to mutate. Hence, these represent key druggable targets for novel compounds against this virus family. In this respect, the identification of highly effective and innovative pharmacological strategies is of paramount importance for the treatment and/or prophylaxis of the current pandemic but potentially also for future and unavoidable outbreaks of human pathogenic coronaviruses.

Methylene blue is a potent and broad-spectrum inhibitor against Zika virus in vitro and in vivo.

Many flaviviruses including the Dengue virus (DENV), Zika virus (ZIKV), West Nile virus, Yellow Fever virus, and Japanese encephalitis virus are significant human pathogens, unfortunately without any specific therapy. Here, we demonstrate that methylene blue, an FDA-approved drug, is a broad-spectrum and potent antiviral against Zika virus and Dengue virus both in vitro and in vivo. We found that methylene blue can considerably inhibit the interactions between viral protease NS3 and its NS2B co-factor, inhibit viral protease activity, inhibit viral growth, protect 3D mini-brain organoids from ZIKV infection, and reduce viremia in a mouse model. Mechanistic studies confirmed that methylene blue works in both entry and post entry steps, reduces virus production in replicon cells and inhibited production of processed NS3 protein. Overall, we have shown that methylene blue is a potent antiviral for management of flavivirus infections, particularly for Zika virus. As an FDA-approved drug, methylene blue is well-tolerated for human use. Therefore, methylene blue represents a promising and easily developed therapy for management of infections by ZIKV and other flaviviruses.

Protease-Resistant Growth Factor Formulations for the Healing of Chronic Wounds.

Objective: Chronic wounds are long-term nonhealing wounds that are refractory to treatment. These wounds can present elevated protease levels, leading to rapid degradation of native and exogenously added growth factors. This work focused on developing a protease-resistant growth factor formulation for treatment of chronic wounds presented with high protease activity. Approach: This study developed protease-resistant growth factor formulations comprising elastin-like peptides (ELPs) fused with a known protease inhibitor peptide or growth factor. The ELP component of the fusion proteins allows assembly of heterogeneous nanoparticles (NPs) putting the inhibitor in close proximity to the growth factor to be protected. Results: We show successful preservation of growth factor activity in high human neutrophil elastase (HNE) environment and in human chronic wound fluid derived from patients. We further show that these NPs result in enhanced collagen remodeling and resolution of inflammation in a full thickness wound supplemented with HNE in genetically diabetic mice. Innovation: Development of heterogeneous NPs that put the protease inhibitor in close proximity of the growth factor. Moreover, the modular nature of the NPs allows for protection of multiple growth factors by the same inhibitor without changing the amino acid sequence of the growth factor. Conclusion: Our results indicate that the developed NPs hold tremendous promise in chronic wound healing therapy and may further help the translation of growth factor therapies to clinic. The customizable template for the NP design allows for multifaceted use across several fields in research and medicine.

Optimizing the Profile of [99mTc]Tc-NT(7-13) Tracers in Pancreatic Cancer Models by Means of Protease Inhibitors.

BACKGROUND: The overexpression of neurotensin subtype 1 receptors (NTS1Rs) in human tumors may be elegantly exploited for directing neurotensin (NT)-based radionuclide carriers specifically to cancer sites for theranostic purposes. We have recently shown that [99mTc]Tc-DT1 ([99mTc]Tc-[N4-Gly7]NT(7-13)) and [99mTc]Tc-DT5 ([99mTc]Tc-[N4-ßAla7,Dab9]NT(7-13)) show notably improved uptake in human colon adenocarcinoma WiDr xenografts in mice treated with neprilysin (NEP) inhibitors and/or angiotensin-converting enzyme (ACE) inhibitors compared with untreated controls. Aiming toward translation of this promising approach in NTS1R-positive pancreatic ductal adenocarcinoma (PDAC) patients, we now report on the impact of registered NEP/ACE inhibitors on the performance of [99mTc]Tc-DT1 and [99mTc]Tc-DT5 in pancreatic cancer models. METHODS: The cellular uptake of [99mTc]Tc-DT1 and [99mTc]Tc-DT5 was tested in a panel of pancreatic cell lines, and their stability was assessed in mice treated or not treated with Entresto, lisinopril, or their combinations. Biodistribution was conducted in severe combined immunodeficiency (SCID) mice bearing pancreatic AsPC-1 xenografts. RESULTS: The Entresto + lisinopril combination maximized the metabolic stability of the fast-internalizing [99mTc]Tc-DT1 in mice, resulting in notably enhanced tumor uptake (7.05 ± 0.80% injected activity (IA)/g vs. 1.25 ± 0.80% IA/g in non-treated controls at 4 h post-injection; p < 0.0001). CONCLUSIONS: This study has shown the feasibility of optimizing the uptake of [99mTc]Tc-DT1 in pancreatic cancer models with the aid of clinically established NEP/ACE inhibitors, in favor of clinical translation prospects.

Beneficial Effects of Sacubitril/Valsartan at Low Doses in an Asian Real-World Heart Failure Population.

This study aimed at analyzing the clinical profile of real-world patients with heart failure with reduced ejection fraction (HFrEF) and evaluating the safety and efficacy of sacubitril/valsartan among Asian patients in daily practice. We conducted a single-center prospective observational cohort study of HFrEF patients treated with sacubitril/valsartan from September 2017 to September 2018 with a follow-up of 6 months. The mean (SD) age of the 110 patients enrolled was 59.7 ± 13.3, 85 (77.3%) were men and 41 (37.3%) had ischemic cardiomyopathy. Thirty-one (27.2%) patients with low systolic blood pressure initiated sacubitril/valsartan on a tiny dose of 12/13 mg. Despite the low mean daily dose achieved in real world mainly because of hypotension, left ventricular ejection fraction increased significantly from 35.4 ± 8.9% at baseline to 43.0 ± 12.2% after 6-month follow-up (P < 0.001). We also observed a significant improvement in a 6-minute walk test (6-MWT) distance and N-terminal pro-B-type natriuretic peptide (NT-proBNP) concentration reduction. No severe adverse event was recorded. Low dose sacubitril/valsartan induces beneficial cardiac reverse remodeling and improves clinical functional performance in real-world HFrEF patients without severe adverse effect. A tiny initial dose may enhance tolerability and reduce discontinuation rate by minimizing hypotension events in patients with low systolic blood pressure. These data further support using low-dose sacubitril/valsartan among eligible patients with HFrEF in Asia.

The TLC-NOSF (Technology Lipido-Colloid Plus Nano-Oligo Saccharide Factor) protease inhibitor for the treatment of ulceration in rheumatic disease A case report.

Cutaneous Lupus Erithematosus is one of the most common manifestation of Systemic Lupus Erithematosus and can be featured by the onset of cutaneous vasculitis which can bring to skin ulcers, expecially on the extremities. The "common" aetiopathogenesis can be summarized as following: 1) an antiself response to the endothelial cells which brings to frequent ischemic or thrombotic episodes, 2) the drugs therapy; recently authors have been demostrated a correlation between Metalloproteinase Matrix (MMP) and Cutaneous LES. Here we present the case of a 33 y.o. woman affected by a rheumatic disorder, which has developed a chronic ulcer on her left leg. After several and different unsuccessful approaches, as homologous and autologous skin graft, and considering both the refusal of other surgery even if enhanced by Negative Pressure Therapy and the compromised vascularization which contraindicated the use of flaps, we decided to use a dressing based on the TLC-NOSF (Technology Lipido-Colloid plus Nano-Oligo Saccharide Factor) protease inhibitor, a metalloproteinase regulator. The dressing was changed 2 times/week for the first 2 months and 1 time/week for other 2 months. The ulcer became smaller at every session and we obtained a full coverage at 4th month. KEY WORDS: Nano-oligo saccharide factor, Wound.

Topical doxycycline monohydrate hydrogel 1% targeting proteases/PAR2 pathway is a novel therapeutic for atopic dermatitis.

Atopic Dermatitis (AD) is characterized by skin barrier disruption and an aberrant immune response. Doxycycline is tetracycline antibiotics broadly used systemically to treat inflammatory dermatologic conditions. Several studies have shown doxycycline has anti-inflammatory and pro-healing properties, mainly by blocking tissue proteolytic activity. It is our hypothesis that daily application of a novel doxycycline topical formulation in AD subjects will reduce severity of the disease, by blocking cutaneous proteases activity and restoring skin barrier function and inflammation. To test this hypothesis, we performed a proof of concept, open-label clinical study. Subjects enrolled in the study (n = 15) applied NanoDOX® Hydrogel 1% daily for 4 weeks on a chosen eczematous area. Investigational drug was well tolerated, and no local or systemic adverse events due to investigational drug were reported. Notably, a significant clinical improvement was observed based on a modified Eczema Area & Severity Index (EASI) score of the treated area from start of treatment to 14 and 28 days post-treatment (P < .001). A significant improvement of pruritus was also observed (P = .02). This proof of concept clinical trial is first to explore the impact of a non-systemic doxycycline treatment on AD patients. Our results provide evidence to investigate novel AD treatment strategies targeting cutaneous proteases activity.

Sialorphin Potentiates Effects of [Met5]Enkephalin without Toxicity by Action other than Peptidase Inhibition.

This dose-response study investigated the effects of sialorphin on [Met5]enkephalin (ME)-induced inhibition of contractions in mouse vas deferens and antinociception in male rats. Differences were compared among combinations of three chemical peptidase inhibitors: amastatin, captopril, and phosphoramidon. The ratio of potencies of ME in mouse vas deferens pretreated with both sialorphin (100 µM) and a mixture of the three peptidase inhibitors (1 µM each) was higher than that with the mixture of peptidase inhibitors alone at any dose. Intrathecal administration of sialorphin (100-400 nmol) significantly and dose dependently increased ME (3 nmol)-induced antinociception with the mixture of three peptidase inhibitors (10 nmol each). The degree of antinociception with a combination of any two of the peptidase inhibitors (10 nmol each) in the absence of sialorphin was less than that in the presence of sialorphin (200 nmol). Pretreatment with both sialorphin (200 nmol) and the mixture of three peptidase inhibitors (10 nmol each) produced an approximately 100-fold augmentation in ME (10 nmol)-induced antinociception, but without signs of toxicity such as motor dysfunction in rats. Radioligand receptor binding assay revealed that sialorphin did not affect either binding affinity or maximal binding capacity of [d-Ala2,N-MePhe4,Gly-ol5]enkephalin. These results indicate that sialorphin potentiates the effects of ME without toxicity by a mechanism other than peptidase inhibition and with no effect on its affinity to µ-opioid receptors. SIGNIFICANCE STATEMENT: Sialorphin is regarded as an endogenous peptidase inhibitor that interacts with enkephalin-degrading enzymes. The results of these in vitro and in vivo studies confirm that sialorphin potentiates the effects of [Met5]enkephalin without toxicity by an action other than peptidase inhibition. This suggests that sialorphin offers the advantage of reducing or negating the side effects of opioid drugs and endogenous opioid peptides.