Electrically conductive nanomaterials for cardiac tissue engineering

© 2019 Elsevier B.V. Patient deaths resulting from cardiovascular diseases are increasing across the globe, posing the greatest risk to patients in developed countries. Myocardial infarction, as a result of inadequate blood flow to the myocardium, results in irreversible loss of cardiomyocytes which can lead to heart failure. A sequela of myocardial infarction is scar formation that can alter the normal myocardial architecture and result in arrhythmias. Over the past decade, a myriad of tissue engineering approaches has been developed to fabricate engineered scaffolds for repairing cardiac tissue. This paper highlights the recent application of electrically conductive nanomaterials (carbon and gold-based nanomaterials, and electroactive polymers) to the development of scaffolds for cardiac tissue engineering. Moreover, this work summarizes the effects of these nanomaterials on cardiac cell behavior such as proliferation and migration, as well as cardiomyogenic differentiation in stem cells

Pharmacological Modulators of Sphingolipid Metabolism for the Treatment of Cystic Fibrosis Lung Inflammation

Cystic Fibrosis (CF) lung disease is characterised by progressive chronic infection and inflammation of the airways. This prolonged airway inflammatory response leads to irreversible lung damage and fibrosis which is believed to be driven by two distinct, coordinated events: a) a defective cystic fibrosis transmembrane regulator (CFTR) causes airway surface dehydration and increased mucus viscosity leading to chronic colonization with Pseudomonas aeruginosa (P.aeruginosa) (Boucher, 2007); b) mutated CFTR triggers the generation of pro-inflammatory and chemotactic cytokines orchestrated by bronchial epithelial cells, independently of infection (Rubin, 2007; Elizur et al., 2008). The chemokine IL-8, abundantly expressed at sites of chronic inflammation, seems to play a major role in driving the formation of neutrophil (PMN)-rich exudates into the lung of CF patients (Khan et al., 1995; Noah et al., 1997; DiMango et al., 1998; Puchelle et al., 2001; Joseph et al., 2005; Perez et al., 2007). Therefore, reduction of the exaggerated production of IL-8 is key therapeutic target in CF. Anti-inflammatory drugs are an attractive therapeutic tool in CF aimed to decrease the rate of decline in lung function. However, the inherent complexity of the inflammatory response combined with the obvious dependency on this response to contain infection and the side effect profiles of common anti-inflammatories, have made identifying the most suitable therapy a major priority. Consensus is growing on sphingolipids (SLs) as novel targets to cure pulmonary disorders including CF, since modulation of cellular ceramide reduces lung inflammation (Lahiri and Futerman, 2007; Uhlig and Gulbins, 2008). The results in the area of ceramide and CF pathophysiology are very interesting, although contradicting due to the animal models used and methods of ceramide detection (Wojewodka , 2011). The accumulation of ceramide has been identified as one of the key regulators of inflammation in CF airways in different CFTR-/- mouse models (Teichgraber, 2008). On the contrary, decreased ceramide levels have been shown in CFTR ko mice (Guibault, 2008). The possible explanation for this discrepancy seems to be the special diet required for CFTR ko mice, that severely affects the concentration of SLs. Other possible causes, such as genetic determinants, could influence individual levels of SLs (Hicks, 2009). In a different study, no significant difference has been found in basal ceramide levels in immortalised CF bronchial epithelial cells and lung homogenate from CFTR ko mice compared to wild type cells and mice (Yu, 2009). Very importantly, ceramide has been demonstrated to accumulate in the lower airways of CF patients and to be positively associated with neutrophilic inflammation (Brodlie, 2010), supporting the hypothesis that reduction of ceramide may be a therapeutic target for CF lung inflammation. Extending our previous study (Dechecchi, 2008), we have recently demonstrated that the iminosugar N-butyldeoxynojirimycin (miglustat), an inhibitor of the first step in glycosphingolipid (GSL) biosynthesis, reducing the P.aeruginosa induced immunoreactive ceramide expression, produces an anti-inflammatory effect in human bronchial epithelial cells in vitro and down-regulates the neutrophil chemotaxis in murine lungs in vivo (Dechecchi, 2011). These findings strengthen the notion that the metabolism of SLs can be manipulated as a therapeutic option for CF lung disease. With regard to new treatments for CF lung pathology, miglustat deserves great attention since it restores CFTR function in respiratory and pancreatic cells in vitro (Norez, 2006; Dechecchi, 2008) and in CF mice (Lubamba, 2009) and produces an anti-inflammatory effect in vitro and in vivo Dechecchi, 2011). Notably, miglustat is a FDA-approved and EMA−designated orally bioavailable orphan drug, used in Europe and USA for the treatment of Gaucher disease and other GSL storage diseases. In this chapter we review the pre-clinical evidence on the anti-inflammatory effect of miglustat in comparative effectiveness studies with the SL inhibitor amitriptyline and the glucocorticoid (GC) dexamethasone. Importance will be placed on the efficacy of each anti-inflammatory molecule to balance between the anti-inflammatory activity and possible impairment of the host defence

Exploratory data on the clinical efficacy of monoclonal antibodies against SARS-CoV-2 Omicron variant of concern

Background: Recent in-vitro data have shown that the activity of monoclonal antibodies (mAbs) targeting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) varies according to the variant of concern (VOC). No studies have compared the clinical efficacy of different mAbs against Omicron VOC. Methods: The MANTICO trial is a non-inferiority randomised controlled trial comparing the clinical efficacy of early treatments with bamlanivimab/etesevimab, casirivimab/imdevimab, and sotrovimab in outpatients aged 50 or older with mild-to-moderate SARS-CoV-2 infection. As the patient enrolment was interrupted for possible futility after the onset of the Omicron wave, the analysis was performed according to the SARS-CoV-2 VOC. The primary outcome was coronavirus disease 2019 (COVID-19) progression (hospitalisation, need of supplemental oxygen therapy, or death through day 14). Secondary outcomes included the time to symptom resolution, assessed using the product-limit method. Kaplan-Meier estimator and Cox proportional hazard model were used to assess the association with predictors. Log rank test was used to compare survival functions. Results: Overall, 319 patients were included. Among 141 patients infected with Delta, no COVID-19 progression was recorded, and the time to symptom resolution did not differ significantly between treatment groups (Log-rank Chi-square 0.22, p 0.90). Among 170 patients infected with Omicron (80.6% BA.1 and 19.4% BA.1.1), two COVID-19 progressions were recorded, both in the bamlanivimab/etesevimab group, and the median time to symptom resolution was 5 days shorter in the sotrovimab group compared with the bamlanivimab/etesevimab and casirivimab/imdevimab groups (HR 0.53 and HR 0.45, 95% CI 0.36-0.77 and 95% CI 0.30-0.67, p<0.01). Conclusions: Our data suggest that, among adult outpatients with mild-to-moderate SARS-CoV-2 infection due to Omicron BA.1 and BA.1.1, early treatment with sotrovimab reduces the time to recovery compared with casirivimab/imdevimab and bamlanivimab/etesevimab. In the same population, early treatment with casirivimab/imdevimab may maintain a role in preventing COVID-19 progression. The generalisability of trial results is substantially limited by the early discontinuation of the trial and firm conclusions cannot be drawn. Funding: This trial was funded by the Italian Medicines Agency (Agenzia Italiana del Farmaco, AIFA). The VOC identification was funded by the ORCHESTRA (Connecting European Cohorts to Increase Common and Effective Response to SARS-CoV-2 Pandemic) project, which has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement number 101016167. Clinical trial number: NCT05205759

Role of adipose tissue in melanoma cancer microenvironment and progression

Background:An epidemiological association between excess weight and increased risk of cancer has been described in melanoma, for which the physiopathological mechanisms are still unknown. The study of tumor microenvironment and of the role of adipocytes in cancer development, progression and metastasis has recently received great interest. However, the role of peritumoral adipocytes has been characterized only in a few types of cancer, and in melanoma it still remains to be defined.Methods:We investigated the interactions between adipocytes and melanoma cells using an in vitro co-culture system. We studied the morphological and functional properties of 3T3-L1 adipocytes before and after co-culture with A375 melanoma cells, in order to assess the role of adipocytes on melanoma migration.Results:Morphological analysis showed that after 6 days of co-culture 3T3-L1 adipocytes were reduced in number and size. Moreover, we observed the appearance of dedifferentiated cells with a fibroblast-like phenotype that were not present in controls and that had lost the expression of some adipocyte-specific genes, and increased the expression of collagen, metalloproteinases and genes typical of dedifferentiation processes. Through the Matrigel Invasion Test, as well the Scratch Test, it was possible to observe that co-culture with adipocytes induced in melanoma cells increased migratory capacity, as compared with controls. In particular, the increase in migration observed in co-culture was suppressed after adding the protein SFRP-5 in the medium, supporting the involvement of the Wnt5a pathway. The activation of this pathway was further characterized by immunofluorescence and western blot analysis, showing in melanocytes in co-culture the activation of β-catenin and LEF-1, two transcription factors involved in migration processes, neo-angiogenesis and metastasis.Conclusions:These data allow us to hypothesize a dedifferentiation process of adipocytes toward fibroblast-like cells, which can promote migration of melanoma cells through activation of Wnt5a and the intracellular pathways of β-catenin and LEF-1

In vitro model of chronological aging of adipocytes: Interrelationships with hypoxia and oxidation

Aging is a physiological process characterized by an age-progressive decline in intrinsic physiological functions, with an increased risk of developing chronic metabolic conditions, such as insulin resistance and diabetes. Furthermore, from a physiopathological point of view, several authors describe an association between oxidative stress, hypoxia and these metabolic conditions. It had been suggested that adipose tissue (AT) dysfunction, senescent cell accumulation and proinflammatory pathways may be involved in this processes. The purpose of this study was to develop an in vitro model to study the progressive morphological and functional changes of adipocytes with aging, in standard culture conditions and after severe hypoxia and hydrogen peroxide treatment. We evaluated the degree of apoptosis and intracellular reactive oxygen species (ROS) accumulation as well as the gene expression profile of aging adipocytes. Our results show that aged adipocytes become senescent, undergo apoptosis, accumulate ROS, and present an inflammatory profile with an increase in mRNA expression level of key proteins related to the remodeling of the extracellular matrix (ECM). Aged adipocytes present increased levels of p53, p21 and p16, key regulators of senescence, and a decrease in SIRT-1 protein compared to younger cells. Moreover, adipocytes aged in hypoxia or in oxidative stress conditions represent a model of accelerated aging with a decrease in their area, a greater proportion of apoptotic and of intracellular ROS accumulation compared to controls. This study characterizes the progressive morphological and functional changes in aging adipocytes during prolonged cell cultures and explores the addictive effects of hypoxia and oxidation, given at different stages of cellular maturation and senescence

PLCB3 in pro-inflammatory signaling in bronchial epithelial cells

No abstract availabl

Active surveillance for early detection of SARS-CoV-2 infections across high-risk community key populations.

Up to June 15th 2021, the Severe Acute Respiratory Syndrome Coronavirus type 2 (SARS- CoV-2) pandemic caused 4,228,434 cases and 126,099 deaths in Italy [1]. At the beginning of the second pandemic wave, starting from October 2020 onwards, the Italian government tailored containment measures at regional level in accordance with cases dynamic. The ongoing regional surveillance systems focused mainly on contact tracing and elderly in long-term care facilities [2,3]. An ad hoc active surveillance covering not routinely surveyed fragile key-populations in the community in a city of 250,000 inhabitants in the North East of Italy was established with the goal of improving public health responses

PLCB3 cooperates with the Toll-like receptors' signaling cascade enhancing P.aeruginosa-dependent IL-8 expression in bronchial epithelial cells

An excessive neutrophilic inflammation, initially orchestrated by bronchial epithelial cells and amplified by chronic bacterial infection with P.aeruginosa, leads to progressive tissue destruction in the lungs of patients affected by Cystic Fibrosis. The discovery of novel molecular targets may help to develop more effective anti-inflammatory drugs. In this issue, we report that association study conducted on a cohort of F508del homozygous cystic fibrosis patients with either severe or mild progression of lung disease, showed the implication of the nonsynonymous single-nucleotide polymorphism C2534T of the phospholipase C-\uf0623 (PLCB3) gene in the neutrophil recruitment. Studies performed in IB3-1 and CuFi-1 bronchial epithelial cells exposed to P.aeruginosa revealed that PLCB3 is implicated in ATP releasing from the cells and subsequent activation of purinergic receptors, intracellular calcium (Ca2+)i signaling, activation of the protein kinase C\uf061 and C\uf062 and of the nuclear transcription factor NF-\uf06bB p65. Thus, the pro-inflammatory pathway regulated by PLCB3 acts by potentiating the Toll-like Receptors\u2019 signaling cascade leading to enhanced IL-8 expression in bronchial epithelial cells. Concluding, PLCB3 may represent an interesting molecular target to attenuate the excessive recruitment of neutrophils without completely abolishing the immune response