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TLRs, including TLR4, play a crucial role in inflammatory-based diseases, and TLR4 has been identified as a therapeutic target for pharmacological intervention. In previous studies, we investigated the potential of FP7, a novel synthetic glycolipid active as a TLR4 antagonist, to inhibit haematopoietic and non-haematopoietic MyD88-dependent TLR4 pro-inflammatory signalling. The main aim of this study was to investigate the action of FP7 and its derivative FP12 on MyD88-independent TLR4 signalling in THP-1 derived macrophages. Western blotting, Ab array and ELISA approaches were used to explore the effect of FP7 and FP12 on TRIF-dependent TLR4 functional activity in response to LPS and other endogenous TLR4 ligands in THP-1 macrophages. A different kinetic in the inhibition of endotoxin-driven TBK1, IRF3 and STAT1 phosphorylation was observed using different LPS chemotypes. Following activation of TLR4 by LPS, data revealed that FP7 and FP12 inhibited TBK1, IRF3 and STAT1 phosphorylation which was associated with down-regulation IFN-β and IP-10. Specific blockage of the IFN type one receptor showed that these novel molecules inhibited TRIF-dependent TLR4 signalling via IFN-β pathways. These results add novel information on the mechanism of action of monosaccharide FP derivatives. The inhibition of the TRIF-dependent pathway in human macrophages suggests potential therapeutic uses for these novel TLR4 antagonists in pharmacological interventions on inflammatory diseases. [ABSTRACT FROM AUTHOR]

Purpose: The partial ineffectiveness and side effects of inflammatory bowel disease (IBD) current therapies drive basic research to look for new therapeutic target in order to develop new drug lead. Considering the pivotal role played by toll-like receptors (TLRs) in gut inflammation, we evaluate here the therapeutic effect of the synthetic glycolipid TLR4 antagonist FP7. Methods: The anti-inflammatory effect of FP7, active as TLR4 antagonist, was evaluated on peripheral blood mononuclear cells (PBMCs) and lamina propria mononuclear cells (LPMCs) isolated from IBD patients, and in a mouse model of ulcerative colitis. Results: FP7 strongly reduced the inflammatory responses induced by lipopolysaccharide (LPS) in vitro, due to its capacity to compete with LPS for the binding of TLR4/MD-2 receptor complex thus inhibiting both the MyD88- and TRIF-dependent inflammatory pathways. Colitic mice treated with FP7 exhibit reduced colonic inflammation and decreased levels of pro-inflammatory cytokines. Conclusions: This study suggests that TLR4 chemical modulation can be an effective therapeutic approach to IBD. The selectivity of FP7 on TLR4 makes this molecule a promising drug lead for new small molecules-based treatments. [ABSTRACT FROM AUTHOR]

The structure-activity relationship was investigated in a series of synthetic TLR4 antagonists formed by a glucosamine core linked to two phosphate esters and two linear carbon chains. Molecular modeling showed that the compounds with 10, 12, and 14 carbons chains are associated with higher stabilization of the MD-2/TLR4 antagonist conformation than in the case of the C16 variant. Binding experiments with human MD-2 showed that the C12 and C14 variants have higher affinity than C10, while the C16 variant did not interact with the protein. The molecules, with the exception of the C16 variant, inhibited the LPS-stimulated TLR4 signal in human and murine cells, and the antagonist potency mirrored the MD-2 affinity calculated from in vitro binding experiments. Fourier-transform infrared, nuclear magnetic resonance, and small angle X-ray scattering measurements suggested that the aggregation state in aqueous solution depends on fatty acid chain lengths and that this property can influence TLR4 activity in this series of compounds. [ABSTRACT FROM AUTHOR]

We recently reported on the activity of cationic amphiphiles in inhibiting TLR4 activation and subsequent production of inflammatory cytokines in cells and in animal models. Starting from the assumption that opportunely designed cationic amphiphiles can behave as CD14/MD-2 ligands and therefore modulate the TLR4 signaling, we present here a panel of amphiphilic guanidinocalixarenes whose structure was computationally optimized to dock into MD-2 and CD14 binding sites. Some of these calixarenes were active in inhibiting, in a dose-dependent way, the LPS-stimulated TLR4 activation and TLR4-dependent cytokine production in human and mouse cells. Moreover, guanidinocalixarenes also inhibited TLR4 signaling when TLR4 was activated by a non-LPS stimulus, the plant lectin PHA. While the activity of guanidinocalixarenes in inhibiting LPS toxic action has previously been related to their capacity to bind LPS, we suggest a direct antagonist effect of calixarenes on TLR4/MD-2 dimerization, pointing at the calixarene moiety as a potential scaffold for the development of new TLR4-directed therapeutics. [ABSTRACT FROM AUTHOR]

Abstract Acetobacter pasteurianus is an acetic acid-producing Gram-negative bacterium commonly found associated with plants and plant products and widely used in the production of fermented foods, such as kefir and vinegar. Due to the acid conditions of the bacterium living habitat, uncommon structural features composing its cell envelope are expected. In the present work we have investigated the A. pasteurianus CIP103108 lipopolysaccharide (LPS) structure and immunoactivity. The structure of the lipid A and of two different O -polysaccharides was assessed. Furthermore, immunological studies with human cells showed a low immunostimulant activity of the isolated LPS, in addition to a slight capability to lower the NF-kB activation upon stimulation by toxic LPS. [ABSTRACT FROM AUTHOR]

(1) Background: Obstructive sleep apnea (OSA) is the most common sleep-related breathing disorder and is characterized by recurrent episodes of complete or partial obstruction of the upper airway, leading to reduced or absent breathing during sleep. A nocturnal upper airway collapse is often multi-levelled. The aim of this communication is to describe a 3D multi-level surgery setting in OSA pathology, introducing new surgical approaches, such as 4K-3D endoscopic visualization for the tongue base approach with the aid of a coblator and exoscopic visualization in the palatal approach. (2) Methods: Seven patients affected by OSA underwent 3D Barbed Reposition Pharyngoplasty (BRP) surgery associated with transoral coblation tongue base reduction and nose surgery. (3) Results: No patients experienced intra-operative, post-operative or delayed complications. For OSA multi-level 3D surgery, it took less than 2 h: the median 3D system setting time was 12.5 ± 2.3 min; the overall procedure time was 59.3 ± 26 min. (4) Conclusions: The use of the 4K-3D endoscope and coblator for tongue base resectioning and of the 3D exoscope for lateral pharyngoplasty represents an excellent system in multi-level OSA related surgery that could reduce the time and the costs compared to those of robotic surgery. [ABSTRACT FROM AUTHOR]

Introduction: Avascular necrosis of femoral head (AVN) is 1 of the main factors causing disability in young adults. Hip prosthesis can be considered an effective treatment of the painful symptoms but it is a major surgical intervention for this type of population. Thus, a large space should be left to therapeutic alternatives such as regenerative medicine. This retrospective study evaluates 52 AVN treated by core decompression, bone chips allograft, fibrin platelet-rich plasma (PRF) and concentrated autologous mesenchymal stromal cells (MSCs). Methods: The AVN was diagnosed using magnetic resonance imaging (MRI) and graded according to ARCO classification: a patient was classified stage 1 (21 patients), stage 3 (26 patients), and 4 patients were classified as stage 4. We evaluated patients with functional scores (Harris Hip Score) and radiological analysis at 3, 6, 12 and 24 months after the procedure. Patients requiring prosthetic replacement of the joint were included; in these cases, follow-up was interrupted at the time of the joint replacement procedure. Results: Our statistical analysis showed differences between survived and failed treatments, in terms of patient profile and ARCO radiological classification. The best result occurred in patients with ARCO grades 1 and 2, while the more advanced grades showed a high failure rate. It is interesting to note that ARCO quantification, conceived as the joint surface involved in the necrosis, has a negative influence on the outcome of the procedure. Indeed, patients affected by ARCO 3a, where necrosis involved a small portion of the femoral epiphysis and the collapse of the articular surface was limited to 2 mm, showed results similar to those obtained in patients with ARCO 1 and 2. Conclusions: In conclusion, compared with the alternative technique of decompression, our data suggest that post-collapse cases with a small area of necrosis and the use of bone grafts may show better results compared to those of the literature. [ABSTRACT FROM AUTHOR]

Severe coronavirus disease 2019 (COVID-19) is characterized by overproduction of immune mediators, but the role of interferons (IFNs) of the type I (IFN-I) or type III (IFN-III) families remains debated. We scrutinized the production of IFNs along the respiratory tract of COVID-19 patients and found that high levels of IFN-III, and to a lesser extent IFN-I, characterize the upper airways of patients with high viral burden but reduced disease risk or severity. Production of specific IFN-III, but not IFN-I, members denotes patients with a mild pathology and efficiently drives the transcription of genes that protect against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In contrast, compared to subjects with other infectious or noninfectious lung pathologies, IFNs are overrepresented in the lower airways of patients with severe COVID-19 that exhibit gene pathways associated with increased apoptosis and decreased proliferation. Our data demonstrate a dynamic production of IFNs in SARS-CoV-2-infected patients and show IFNs play opposing roles at distinct anatomical sites. [Display omitted] • IFN expression in COVID-19 varies based on location, viral load, age, and severity • IFN-λ1 and IFN-λ3 drive protective ISGs in the upper airways of mildly ill patients • Critical patients express IFN-αβ and IFN-λ2 and have low ISGs and high p53 expression • Epithelial cells efficiently produce protective IFN-λ1, while cDCs express IFN-λ2,3 An in-depth analysis of IFNs in COVID-19 reveals differences in their roles based on anatomical location, viral load, age, and disease severity. In the upper respiratory tract, high levels of IFN-III are protective and result in mild disease in spite of higher SARS-CoV-2 viral burden, while the lower airways of patients with severe COVID-19 demonstrate elevated IFN-I and IFN-III, cell death, and a reduction in IFN-stimulated genes. [ABSTRACT FROM AUTHOR]