Extracellular vesicles (EVs) are heterogeneous membranous particles released from the cells through different biogenetic and secretory mechanisms. We now conceive EVs as shuttles mediating cellular communication, carrying a variety of molecules resulting from intracellular homeostatic mechanisms. The RNA is a widely detected cargo and, impressively, a recognized functional intermediate that elects EVs as modulators of cancer cell phenotypes, determinants of disease spreading, cell surrogates in regenerative medicine, and a source for non‐invasive molecular diagnostics. The mechanistic elucidation of the intracellular events responsible for the engagement of RNA into EVs will significantly improve the comprehension and possibly the prediction of EV “quality” in association with cell physiology. Interestingly, the application of multidisciplinary approaches, including biochemical as well as cell‐based and computational strategies, is increasingly revealing an active RNA‐packaging process implicating RNA‐binding proteins (RBPs) in the sorting of coding and non‐coding RNAs. In this review, we provide a comprehensive view of RBPs recently emerging as part of the EV biology, considering the scenarios where: (i) individual RBPs were detected in EVs along with their RNA substrates, (ii) RBPs were detected in EVs with inferred RNA targets, and (iii) EV‐transcripts were found to harbour sequence motifs mirroring the activity of RBPs. Proteins so far identified are members of the hnRNP family (hnRNPA2B1, hnRNPC1, hnRNPG, hnRNPH1, hnRNPK, and hnRNPQ), as well as YBX1, HuR, AGO2, IGF2BP1, MEX3C, ANXA2, ALIX, NCL, FUS, TDP‐43, MVP, LIN28, SRP9/14, QKI, and TERT. We describe the RBPs based on protein domain features, current knowledge on the association with human diseases, recognition of RNA consensus motifs, and the need to clarify the functional significance in different cellular contexts. We also summarize data on previously identified RBP inhibitor small molecules that could also be introduced in EV research as potential modulators of vesicular RNA sorting.

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Surgical repair of large muscular defects requires the use of autologous graft transfer or prosthetic material. Naturally derived matrices are biocompatible materials obtained by tissue decellularization and are commonly used in clinical practice. Despite promising applications described in the literature, the use of acellular matrices to repair large defects has been only partially successful, highlighting the need for more efficient constructs. Scaffold recellularization by means of tissue engineering may improve not only the structure of the matrix, but also its ability to functionally interact with the host. The development of such a complex construct is challenging, due to the complexity of the native organ architecture and the difficulties in recreating the cellular niche with both proliferative and differentiating potential during growth or after damage. In this study, we tested a mouse decellularized diaphragmatic extracellular matrix (ECM) previously described by our group, for the generation of a cellular skeletal muscle construct with functional features. The decellularized matrix was stored using different conditions to mimic the off‐the‐shelf clinical need. Pediatric human muscle precursors were seeded into the decellularized scaffold, demonstrating proliferation and differentiation capability, giving rise to a functioning three‐dimensional skeletal muscle structure. Furthermore, we exposed the engineered construct to cardiotoxin injury and demonstrated its ability to activate a regenerative response in vitro promoting cell self‐renewal and a positive ECM remodeling. Functional reconstruction of an engineered skeletal muscle with maintenance of a stem cell pool makes this a promising tool toward future clinical applications in diaphragmatic regeneration. Stem Cells Translational Medicine 2019;8:858&869

Background the aim of this study was to examine the cross-sectional and longitudinal associations of different multimorbidity patterns with physical frailty in older adults. Methods we used data from the Swedish National study on Aging and Care in Kungsholmen to generate a physical frailty measure, and clusters of participants with similar multimorbidity patterns were identified through fuzzy c-means cluster analyses. The cross-sectional association (n = 2,534) between multimorbidity clusters and physical frailty was measured through logistic regression analyses. Six- (n = 2,122) and 12-year (n = 2,140) longitudinal associations were determined through multinomial logistic regression analyses. Results six multimorbidity patterns were identified at baseline: psychiatric diseases; cardiovascular diseases, anaemia and dementia; sensory impairments and cancer; metabolic and sleep disorders; musculoskeletal, respiratory and gastrointestinal diseases; and an unspecific pattern lacking any overrepresented diseases. Cross-sectionally, each pattern was associated with physical frailty compared with the unspecific pattern. Over 6 years, the psychiatric diseases (relative risk ratio [RRR]: 3.04; 95% confidence intervals [CI]: 1.59–5.79); cardiovascular diseases, anaemia and dementia (RRR 2.25; 95% CI: 1.13–4.49) and metabolic and sleep disorders (RRR 1.99; 95% CI: 1.25–3.16) patterns were associated with incident physical frailty. The cardiovascular diseases, anaemia and dementia (RRR: 4.81; 95% CI: 1.59–14.60); psychiatric diseases (RRR 2.62; 95% CI: 1.45–4.72) and sensory impairments and cancer (RRR 1.87; 95% CI: 1.05–3.35) patterns were more associated with physical frailty, compared with the unspecific pattern, over 12 years. Conclusions we found that older adults with multimorbidity characterised by cardiovascular and neuropsychiatric disease patterns are most susceptible to developing physical frailty.

Skeletal muscle tissue engineering (TE) aims to efficiently repair large congenital and acquired defects. Biological acellular scaffolds are considered a good tool for TE, as decellularization allows structural preservation of tissue extracellular matrix (ECM) and conservation of its unique cytokine reservoir and the ability to support angiogenesis, cell viability, and proliferation. This represents a major advantage compared to synthetic scaffolds, which can acquire these features only after modification and show limited biocompatibility. In this work, we describe the ability of a skeletal muscle acellular scaffold to promote vascularization both ex vivo and in vivo. Specifically, chicken chorioallantoic membrane assay and protein array confirmed the presence of pro-angiogenic molecules in the decellularized tissue such as HGF, VEGF, and SDF-1α. The acellular muscle was implanted in BL6/J mice both subcutaneously and ortotopically. In the first condition, the ECM-derived scaffold appeared vascularized 7 days post-implantation. When the decellularized diaphragm was ortotopically applied, newly formed blood vessels containing CD31+, αSMA+, and vWF+ cells were visible inside the scaffold. Systemic injection of Evans Blue proved function and perfusion of the new vessels, underlying a tissue-regenerative activation. On the contrary, the implantation of a synthetic matrix made of polytetrafluoroethylene used as control was only surrounded by vWF+ cells, with no cell migration inside the scaffold and clear foreign body reaction (giant cells were visible). The molecular profile and the analysis of macrophages confirmed the tendency of the synthetic scaffold to enhance inflammation instead of regeneration. In conclusion, we identified the angiogenic potential of a skeletal muscle-derived acellular scaffold and the pro-regenerative environment activated in vivo, showing clear evidence that the decellularized diaphragm is a suitable candidate for skeletal muscle tissue engineering and regeneration.

The tumor microenvironment evolves during malignant progression with major changes in non-malignant cells, cytokine networks, and the extracellular matrix (ECM). In this study, we aimed to understand how the ECM changes during neoplastic transformation of serous tubal intraepithelial carcinoma lesions (STIC) into high-grade serous ovarian cancers (HGSOC). Analysis of the mechanical properties of human fallopian tubes (FT) and ovaries revealed that normal FT and fimbria had a lower tissue modulus, a measure of stiffness, than normal or diseased ovaries. Proteomic analysis of the matrisome fraction between FT, fimbria, and ovaries showed significant differences in the ECM protein transforming growth factor beta induced (TGFBI -also known as βig-h3). STIC lesions in the fimbria expressed high levels of TGFBI which was predominantly produced by CD163-positive macrophages proximal to STIC epithelial cells. In vitro stimulation of macrophages with TGFβ and IL4 induced secretion of TGFBI, whereas IFNɣ/LPS downregulated macrophage TGFBI expression. Immortalized FT secretory epithelial cells carrying clinically relevant TP53 mutations stimulated macrophages to secrete TGFBI and upregulated integrin αvβ3, a putative TGFBI receptor. Transcriptomic HGSOC datasets showed a significant correlation between TGFBI expression and alternatively activated macrophage signatures. Fibroblasts in HGSOC metastases expressed TGFBI and stimulated macrophage TGFBI production in vitro. Treatment of orthotopic mouse HGSOC tumors with an anti-TGFBI antibody reduced peritoneal tumor size, increased tumor monocytes, and activated β3-expressing unconventional T cells. In conclusion, TGFBI may favor an immunosuppressive microenvironment in STICs that persists in advanced HGSOC. Furthermore, TGFBI may be an effector of the tumorpromoting actions of TGFβ and a potential therapeutic target. Statement of significanceAnalysis of ECM changes during neoplastic transformation reveals a role for TGFBI secreted by macrophages in immunosuppression in early ovarian cancer.Research.

IntroductionCardiovascular benefits deriving from physical activity are well known, but it is unclear whether physical activity trajectories in late life are associated with different risks of cardiovascular diseases.MethodsProgetto Veneto Anziani (Pro.V.A.) is a cohort study of 3099 Italians aged ≥65 years with baseline assessment in 1995–1997 and follow-up visits at 4 and 7 years. Surveillance was extended to 2018 by linkage with hospital and mortality records. Prevalent and incident cardiovascular diseases (coronary heart disease, heart failure and stroke) were identified through clinical examination, questionnaire, or hospital records. Moderate to vigorous physical activity was considered as a time-varying variable. Physical activity trajectories were categorised as: stable-low, high-decreasing, low-increasing and stable-high. Exposure was also assessed at 70, 75, 80 and 85 years.ResultsOverall, physical activity was associated with lower rates of incident cardiovascular diseases. A significant risk reduction was present among men and was stronger earlier in late life (70–75 years). Trajectories of stable-high physical activity were associated with a significantly lower risk of cardiovascular outcomes among men (HR 0.48, 95% CI 0.27 to 0.86) compared with those with stable-low trajectories (p for trend 0.002). No significant association was found with stroke. The greatest cardiovascular risk reduction was observed for >20 min/day of physical activity, and was more marked at 70 years.ConclusionIncreasingly active trajectories of physical activity were associated with lower rates of cardiovascular diseases and overall mortality. Promoting at least 20 min/day of physical activity early in late life seems to provide the greatest cardiovascular benefits.

Multimorbidity and polypharmacy are emerging health priorities and the care of persons with these conditions is complex and challenging. The aim of the present guidelines is to develop recommendations for the clinical management of persons with multimorbidity and/or polypharmacy and to provide evidence-based guidance to improve their quality of care. The recommendations have been produced in keeping with the Grading of Recommendations Assessment, Development and Evaluation (GRADE). Overall, 14 recommendations were issued, focusing on 4 thematic areas: (1.) General Principles; (2.) target population for an individualized approach to care; (3.) individualized care of patients with multimorbidity and/or polypharmacy; (4.) models of care. These recommendations support the provision of individualized care to persons with multimorbidity and/or polypharmacy as well as the prioritization of care through the identification of persons at increased risk of negative health outcomes. Given the limited available evidence, recommendations could not be issued for all the questions defined and, therefore, some aspects related to the complex care of patients with multimorbidity and/or polypharmacy could not be covered in these guidelines. This points to the need for more research in this field and evidence to improve the care of this population.