Synthesis and NLRP3-Inflammasome Inhibitory Activity of the Naturally Occurring Velutone F and of Its Non-Natural Regioisomeric Chalconoids

Plant-derived remedies rich in chalcone-based compounds have been known for centuries in the treatment of specific diseases, and nowadays, the fascinating chalcone framework is considered a useful and, above all, abundant natural chemotype. Velutone F, a new chalconoid from Millettia velutina, exhibits a potent effect as an NLRP3-inflammasome inhibitor; the search for new natural/non-natural lead compounds as NLRP3 inhibitors is a current topical subject in medicinal chemistry. The details of our work toward the synthesis of velutone F and the unknown non-natural regioisomers are herein reported. We used different synthetic strategies both for the construction of the distinctive benzofuran nucleus (BF) and for the key phenylpropenone system (PhP). Importantly, we have disclosed a facile entry to the velutone F via synthetic routes that can also be useful for preparing non-natural analogs, a prerequisite for extensive SAR studies on the new flavonoid class of NLRP3-inhibitors

Mitochondria-Ros Crosstalk in the Control of Cell Death and Aging

Reactive oxygen species (ROS) are highly reactive molecules, mainly generated inside mitochondria that can oxidize DNA, proteins, and lipids. At physiological levels, ROS function as “redox messengers” in intracellular signalling and regulation, whereas excess ROS induce cell death by promoting the intrinsic apoptotic pathway. Recent work has pointed to a further role of ROS in activation of autophagy and their importance in the regulation of aging. This review will focus on mitochondria as producers and targets of ROS and will summarize different proteins that modulate the redox state of the cell. Moreover, the involvement of ROS and mitochondria in different molecular pathways controlling lifespan will be reported, pointing out the role of ROS as a “balance of power,” directing the cell towards life or death

Inflammatory Microenvironment in Early Non-Small Cell Lung Cancer: Exploring the Predictive Value of Radiomics

Patient prognosis is a critical consideration in the treatment decision-making process. Conventionally, patient outcome is related to tumor characteristics, the cancer spread, and the patients’ conditions. However, unexplained differences in survival time are often observed, even among patients with similar clinical and molecular tumor traits. This study investigated how inflammatory radiomic features can correlate with evidence-based biological analyses to provide translated value in assessing clinical outcomes in patients with NSCLC. We analyzed a group of 15 patients with stage I NSCLC who showed extremely different OS outcomes despite apparently harboring the same tumor characteristics. We thus analyzed the inflammatory levels in their tumor microenvironment (TME) either biologically or radiologically, focusing our attention on the NLRP3 cancer-dependent inflammasome pathway. We determined an NLRP3-dependent peritumoral inflammatory status correlated with the outcome of NSCLC patients, with markedly increased OS in those patients with a low rate of NLRP3 activation. We consistently extracted specific radiomic signatures that perfectly discriminated patients’ inflammatory levels and, therefore, their clinical outcomes. We developed and validated a radiomic model unleashing quantitative inflammatory features from CT images with an excellent performance to predict the evolution pattern of NSCLC tumors for a personalized and accelerated patient management in a non-invasive way

Evaluation of the Synovial Effects of Biological and Targeted Synthetic DMARDs in Patients with Psoriatic Arthritis: A Systematic Literature Review and Meta-Analysis

The aims of this systematic literature review (SLR) were to identify the effects of approved biological and targeted synthetic disease modifying antirheumatic drugs (b/tsDMARDs) on synovial membrane of psoriatic arthritis (PsA) patients, and to determine the existence of histological/molecular biomarkers of response to therapy. A search was conducted on MEDLINE, Embase, Scopus, and Cochrane Library (PROSPERO:CRD42022304986) to retrieve data on longitudinal change of biomarkers in paired synovial biopsies and in vitro studies. A meta-analysis was conducted by adopting the standardized mean difference (SMD) as a measure of the effect. Twenty-two studies were included (19 longitudinal, 3 in vitro). In longitudinal studies, TNF inhibitors were the most used drugs, while, for in vitro studies, JAK inhibitors or adalimumab/secukinumab were assessed. The main technique used was immunohistochemistry (longitudinal studies). The meta-analysis showed a significant reduction in both CD3+ lymphocytes (SMD -0.85 [95% CI -1.23; -0.47]) and CD68+ macrophages (sublining, sl) (SMD -0.74 [-1.16; -0.32]) in synovial biopsies from patients treated for 4-12 weeks with bDMARDs. Reduction in CD3+ mostly correlated with clinical response. Despite heterogeneity among the biomarkers evaluated, the reduction in CD3+/CD68+sl cells during the first 3 months of treatment with TNF inhibitors represents the most consistent variation reported in the literature

Defective endoplasmic reticulum-mitochondria contacts and bioenergetics in SEPN1-related myopathy

: SEPN1-related myopathy (SEPN1-RM) is a muscle disorder due to mutations of the SEPN1 gene, which is characterized by muscle weakness and fatigue leading to scoliosis and life-threatening respiratory failure. Core lesions, focal areas of mitochondria depletion in skeletal muscle fibers, are the most common histopathological lesion. SEPN1-RM underlying mechanisms and the precise role of SEPN1 in muscle remained incompletely understood, hindering the development of biomarkers and therapies for this untreatable disease. To investigate the pathophysiological pathways in SEPN1-RM, we performed metabolic studies, calcium and ATP measurements, super-resolution and electron microscopy on in vivo and in vitro models of SEPN1 deficiency as well as muscle biopsies from SEPN1-RM patients. Mouse models of SEPN1 deficiency showed marked alterations in mitochondrial physiology and energy metabolism, suggesting that SEPN1 controls mitochondrial bioenergetics. Moreover, we found that SEPN1 was enriched at the mitochondria-associated membranes (MAM), and was needed for calcium transients between ER and mitochondria, as well as for the integrity of ER-mitochondria contacts. Consistently, loss of SEPN1 in patients was associated with alterations in body composition which correlated with the severity of muscle weakness, and with impaired ER-mitochondria contacts and low ATP levels. Our results indicate a role of SEPN1 as a novel MAM protein involved in mitochondrial bioenergetics. They also identify a systemic bioenergetic component in SEPN1-RM and establish mitochondria as a novel therapeutic target. This role of SEPN1 contributes to explain the fatigue and core lesions in skeletal muscle as well as the body composition abnormalities identified as part of the SEPN1-RM phenotype. Finally, these results point out to an unrecognized interplay between mitochondrial bioenergetics and ER homeostasis in skeletal muscle. They could therefore pave the way to the identification of biomarkers and therapeutic drugs for SEPN1-RM and for other disorders in which muscle ER-mitochondria cross-talk are impaired

A União Europeia entre o alargamento e a vizinhança: os casos dos Balcãs ocidentais e do Cáucaso do sul

O artigo trata as políticas da UE para a sua periferia a leste, com enfoque nos Balcãs ocidentais e no Cáucaso do sul. Partindo de uma abordagem comparativa, o artigo argumenta que a construção de uma ordem regional normativa, com objetivos claros de estabilização por meio da integração de geometria variável, tem encontrado limites. O artigo identifica essas dinâmicas e procura retirar lições da abordagem europeia aos Balcãs e ao Cáucaso

Extranuclear promyelocytic leukemia protein (PML) and p53 down regulation promote cancer by subverting multiple tumor suppression pathways

Il reticolo endoplasmatico (ER) e i mitocondri interagiscono tra di loro in più siti di contatto a formare specifici domini, denominati “membrane associate ai mitocondri” (MAMs), con differenti proprietà biochimiche e un definito set di proteine. È sempre più evidente come i siti di contatto tra mitocondri e ER rappresentino le vie preferenziali per la trasmissione del segnale e si comportino come piattaforme biologiche in cui vie di segnalazione citoplasmatiche e nucleari possano modulare la sensibilità all'apoptosi, come ad esempio manipolando l’omeostasi del segnale calcio (Ca2+) intracellulare. Durante il mio dottorato abbiamo dimostrato come due importanti oncosoppressori, p53 e promyelocytic leukemia protein (PML), localizzino nei siti di contatto ER/MAM dove svolgono un ruolo importante nella modulazione del segnale Ca2+, nella morte cellulare e nel tumore. Abbiamo dimostrato che p53 si arricchisce alle MAMs in seguito a trattamenti antitumorali che portano a morte cellulare. In questi siti, p53 interagisce con la porzione C-terminale della pompa sarco / ER Ca2+ ATPasi (SERCA), cambiando il suo stato ossidativo e, di conseguenza, aumentando l’accumulo del Ca2+ reticolare. Per confermare questi risultati in vivo, abbiamo utilizzato una piattaforma tecnologica innovativa per la microscopia che permette il rilevamento del segnale Ca2+ in una massa tumorale tridimensionale. Utilizzando questa tecnica siamo stati in grado di confermare in vivo che l’oncosoppressore p53 è in grado di modulare l’omeostasi del Ca2+ in risposta alla fototerapia antitumorale (PDT), favorendo la sensibilità delle cellule all’apoptosi e di conseguenza limitando la crescita tumorale. Queste evidenze sottolineano come le MAMs siano importanti domini specializzati dove molti oncosoppressori esercitano la loro attività pro-apoptotica mediante vie mediate dal Ca2+. Nella seconda parte del mio dottorato, abbiamo identificato un nuovo ruolo extranucleare di PML come regolatore negativo dell’autofagia. E’ già noto come l’interfaccia ER-MAM rappresenti anche la piattaforma biologica primaria per la formazione degli autofagosomi e per il meccanismo di sopravvivenza via autofagia. Abbiamo dimostrato come la localizzazione di PML ai siti di contatto ER-mitocondri non sia solo fondamentale per il controllo dell’apoptosi, ma anche per la regolazione dell’autofagia, reprimendo a livello di questi siti la formazione degli autofagosomi e, di conseguenza, l’induzione dell’autofagia. Abbiamo osservato in vivo che l’assenza di PML promuove lo sviluppo tumorale causato da alti livelli di autofagia nel tumore che portano a resistenza contro farmaci antitumorali. Dal momento che alti livelli di autofagia promuovono la secrezione di citochine infiammatorie come l’interleuchina 1-β (IL-1β) e che il maggior complesso coinvolto nel rilascio di IL-1β, il NLRP3 inflammasoma, è stato identificato localizzare nei domini ER/MAMs, studi futuri saranno orientati al ruolo di PML nel processo infiammatorio.The endoplasmic reticulum (ER) and mitochondria join together at multiple contact sites to form specific domains, termed mitochondria-ER associated membranes (MAMs), with distinct biochemical properties and a characteristic set of proteins. There is growing evidence to indicate that contact sites between the mitochondria and ER act as preferential gateways for signal transmission and behave as platforms where components of cytoplasmic and nuclear pathways can modulate the sensitivity to apoptosis, such as by manipulating the rheostat represented by Ca2+ transmission. During my PhD we demonstrated that two master tumor suppressors, p53 and the promyelocytic leukemia protein (PML) localize at the ER/MAM contact sites where they play an important role in modulating Ca2+ signaling, cell death and cancer. We found that p53 becomes enriched at MAM compartments after anticancer treatments enhancing cell death. At these sites, p53 interacts with the C-terminal portion of the sarco/ER Ca2+ATPase (SERCA) pump, changing its oxidative state and, in turn, increasing ER Ca2+ loading. To test the relevance of these findings in an in vivo approach of tumor environment, we used a novel technological platform for the intravital microscopy allowing detection of Ca2+ signaling in a three dimensional tumor mass. Using this technique we were able to confirm in vivo that the tumor suppressor p53 is able to modulate Ca2+ homeostasis in response to a photodynamic cancer therapy (PDT) favoring cells sensitivity to apoptosis and thus in turn limiting tumor growth. These evidences highlighted how the MAMs are important specialized domains where many tumor suppressors exert their pro-apoptotic activities via calcium-mediated pathways. In the second part of my PhD work, we identified a new extra-nuclear role of PML as a negative regulator of autophagy. It is already known that ER–mitochondria interface also represents the primary platform for autophagosome formation and the function of pro-survival autophagy machinery. We provide evidence that the localization of PML at the ER-mitochondria contact sites is fundamental not only for apoptosis control but also for autophagy regulation, repressing at these sites autophagosome formation and, thus, autophagy induction. We observed in vivo that the absence of PML promotes tumor development associated with resistance to anticancer drugs due to increased autophagy levels in the tumor. Since autophagy levels promote the secretion of inflammatory cytokines like interleuchin-1β (IL1β) and the major complex involved in the IL-1β released, the NLRP3 inflammasome, it has been identified at the ER/MAM domains, our future directions will be focused to explore the role of PML in inflammation process

The LRRC8C-STING-p53 axis in T cells: A Ca2+ affair

Up to now, no role has been associated with VRAC channels in T cells. In a recent paper published in Nature Immunology, LRRC8C has been described as an essential component of VRAC in T cells. These data raise the intriguing possibility that the LRRC8C-STING-p53 signaling axis may represent a new inhibitory pathway in T cells that controls their function and adaptive immunity

The Role of Mitochondria in Inflammation: From Cancer to Neurodegenerative Disorders

The main features that are commonly attributed to mitochondria consist of the regulation of cell proliferation, ATP generation, cell death and metabolism. However, recent scientific advances reveal that the intrinsic dynamicity of the mitochondrial compartment also plays a central role in proinflammatory signaling, identifying these organelles as a central platform for the control of innate immunity and the inflammatory response. Thus, mitochondrial dysfunctions have been related to severe chronic inflammatory disorders. Strategies aimed at reestablishing normal mitochondrial physiology could represent both preventive and therapeutic interventions for various pathologies related to exacerbated inflammation. Here, we explore the current understanding of the intricate interplay between mitochondria and the innate immune response in specific inflammatory diseases, such as neurological disorders and cancer

Novel function of the tumor suppressor PML at ER-mitochondria sites in the control of autophagy

Autophagy is a tightly regulated lysosomal degradation process that mediates the sequestration of intracellular entities to form autophagosomes, and their delivery to lysosomes for bulk degradation