Immunomodulatory activity of argentatins A and B isolated from guayule.

Argentatins are secondary metabolites synthesized by guayule (Parthenium argentatum A. Gray) with numerous potential medical applications. In addition to inhibiting insect growth, they are endowed with several pharmacological properties including antimicrobial and antitumorigenic activity. However, their potential as immunomodulators remains unexplored. The aim of the present study was to investigate whether argentatins can modulate the function of the immune system. Human mesenchymal stem cells were treated with argentatins and the production of several anti- and proinflammatory cytokines was evaluated. The effect of argentatins on the polarization of CD4+ T-lymphocytes and macrophages was also assessed. Results demonstrated that argentatins can modulate the production of proinflammatory cytokines and the polarization of cellular phenotypes, including Th2 lymphocytes and M1 macrophages. These findings suggest that argentatins are promising therapeutic agents in autoimmune or allergic diseases, and open new perspectives for the investigation of argentatins in immune response and in the development of more targeted and effective immunomodulatory therapies.

New Mediators in the Crosstalk between Different Adipose Tissues.

Adipose tissue is a multifunctional organ that regulates many physiological processes such as energy homeostasis, nutrition, the regulation of insulin sensitivity, body temperature, and immune response. In this review, we highlight the relevance of the different mediators that control adipose tissue activity through a systematic review of the main players present in white and brown adipose tissues. Among them, inflammatory mediators secreted by the adipose tissue, such as classical adipokines and more recent ones, elements of the immune system infiltrated into the adipose tissue (certain cell types and interleukins), as well as the role of intestinal microbiota and derived metabolites, have been reviewed. Furthermore, anti-obesity mediators that promote the activation of beige adipose tissue, e.g., myokines, thyroid hormones, amino acids, and both long and micro RNAs, are exhaustively examined. Finally, we also analyze therapeutic strategies based on those mediators that have been described to date. In conclusion, novel regulators of obesity, such as microRNAs or microbiota, are being characterized and are promising tools to treat obesity in the future.

The effect of physical exercise on anticancer immunity.

Regular physical activity is associated with lower cancer incidence and mortality, as well as with a lower rate of tumour recurrence. The epidemiological evidence is supported by preclinical studies in animal models showing that regular exercise delays the progression of cancer, including highly aggressive malignancies. Although the mechanisms underlying the antitumorigenic effects of exercise remain to be defined, an improvement in cancer immunosurveillance is likely important, with different immune cell subtypes stimulated by exercise to infiltrate tumours. There is also evidence that immune cells from blood collected after an exercise bout could be used as adoptive cell therapy for cancer. In this Perspective, we address the importance of muscular activity for maintaining a healthy immune system and discuss the effects of a single bout of exercise (that is, 'acute' exercise) and those of 'regular' exercise (that is, repeated bouts) on anticancer immunity, including tumour infiltrates. We also address the postulated mechanisms and the clinical implications of this emerging area of research.

Influence of Cytokines on Inflammatory Eye Diseases: A Citation Network Study.

BACKGROUND: The main objective of this study was to use citation networks to analyze the relationship between different publications on the impact of cytokines at an ocular level and their authors. Furthermore, the different research areas will be identified, and the most cited publications determined. METHODS: A search was performed in the Web of Science (WoS) database using the following keywords: "cytokine", "inflammatory", and "eye disease" for the period from 1990 to October 2021. The Citation Network Explorer and the CiteSpace software were then used to analyze the different publications. RESULTS: 3127 publications with 8955 citations generated on the web were found. The largest number of publications on this topic emerged in 2018 and the authors with the largest number of publications addressing this area of research were Peizeng Yang (1.4%), Aize Kijlstra (1.3%), and Stephen C. Pflugfelder (1.2%). CONCLUSIONS: the citation network has provided a comprehensive and objective analysis of the main studies on the influence of cytokines in ocular inflammatory diseases.

Mesoangioblasts at 20: From the embryonic aorta to the patient bed.

In 2002 we published an article describing a population of vessel-associated progenitors that we termed mesoangioblasts (MABs). During the past decade evidence had accumulated that during muscle development and regeneration things may be more complex than a simple sequence of binary choices (e.g., dorsal vs. ventral somite). LacZ expressing fibroblasts could fuse with unlabelled myoblasts but not among themselves or with other cell types. Bone marrow derived, circulating progenitors were able to participate in muscle regeneration, though in very small percentage. Searching for the embryonic origin of these progenitors, we identified them as originating at least in part from the embryonic aorta and, at later stages, from the microvasculature of skeletal muscle. While continuing to investigate origin and fate of MABs, the fact that they could be expanded in vitro (also from human muscle) and cross the vessel wall, suggested a protocol for the cell therapy of muscular dystrophies. We tested this protocol in mice and dogs before proceeding to the first clinical trial on Duchenne Muscular Dystrophy patients that showed safety but minimal efficacy. In the last years, we have worked to overcome the problem of low engraftment and tried to understand their role as auxiliary myogenic progenitors during development and regeneration.

Application of low-intensity pulsed therapeutic ultrasound on mesenchymal precursors does not affect their cell properties.

Ultrasound is considered a safe and non-invasive tool in regenerative medicine and has been used in the clinic for more than twenty years for applications in bone healing after the approval of the Exogen device, also known as low-intensity pulsed ultrasound (LIPUS). Beyond its effects on bone health, LIPUS has also been investigated for wound healing of soft tissues, with positive results for various cell processes including cell proliferation, migration and angiogenesis. As LIPUS has the potential to treat chronic skin wounds, we sought to evaluate the effects produced by a conventional therapeutic ultrasound device at low intensities (also considered LIPUS) on the migration capacity of mouse and human skin mesenchymal precursors (s-MPs). Cells were stimulated for 3 days (20 minutes per day) using a traditional ultrasound device with the following parameters: 100 mW/cm2 with 20% duty cycle and frequency of 3 MHz. At the parameters used, ultrasound failed to affect s-MP proliferation, with no evident changes in morphology or cell groupings, and no changes at the cytoskeletal level. Further, the migration and invasion ability of s-MPs were unaffected by the ultrasound protocol, and no major changes were detected in the gene/protein expression of ROCK1, integrin ß1, laminin ß1, type I collagen and transforming growth factor ß1. Finally, RNA-seq analysis revealed that only 10 genes were differentially expressed after ultrasound stimulation. Among them, 5 encode for small nuclear RNAs and 2 encode for proteins belonging to the nuclear pore complex. Considering the results overall, while the viability of s-MPs was not affected by ultrasound stimulation and no changes were detected in proliferation/migration, RNA-seq analysis would suggest that s-MPs do respond to ultrasound. The use of 100 mW/cm2 intensity or conventional therapeutic ultrasound devices might not be optimal for the stimulation the properties of cell populations. Future studies should investigate the potential application of ultrasound using variations of the tested parameters.

BMPER is upregulated in obesity and seems to have a role in pericardial adipose stem cells.

Pericardial adipose tissue (PAT), a visceral fat depot enveloping the heart, is an active endocrine organ and a source of free fatty acids and inflammatory cytokines. As in other fat adult tissues, PAT contains a population of adipose stem cells; however, whether these cells and/or their environment play a role in physiopathology is unknown. We analyzed several stem cell-related properties of pericardial adipose stem cells (PSCs) isolated from obese and ex-obese mice. We also performed RNA-sequencing to profile the transcriptional landscape of PSCs isolated from the different diet regimens. Finally, we tested whether these alterations impacted on the properties of cardiac mesoangioblasts isolated from the same mice. We found functional differences between PSCs depending on their source: specifically, PSCs from obese PSC (oPSC) and ex-obese PSC (dPSC) mice showed alterations in apoptosis and migratory capacity when compared with lean, control PSCs, with increased apoptosis in oPSCs and blunted migratory capacity in oPSCs and dPSCs. This was accompanied by different gene expression profiles across the cell types, where we identified some genes altered in obese conditions, such as BMP endothelial cell precursor-derived regulator (BMPER), an important regulator of BMP-related signaling pathways for endothelial cell function. The importance of BMPER in PSCs was confirmed by loss- and gain-of-function studies. Finally, we found an altered production of BMPER and some important chemokines in cardiac mesoangioblasts in obese conditions. Our findings point to BMPER as a potential new regulator of PSC function and suggest that its dysregulation could be associated with obesity and may impact on cardiac cells.

Lifestyle interventions for the prevention and treatment of hypertension.

Hypertension affects approximately one third of the world's adult population and is a major cause of premature death despite considerable advances in pharmacological treatments. Growing evidence supports the use of lifestyle interventions for the prevention and adjuvant treatment of hypertension. In this Review, we provide a summary of the epidemiological research supporting the preventive and antihypertensive effects of major lifestyle interventions (regular physical exercise, body weight management and healthy dietary patterns), as well as other less traditional recommendations such as stress management and the promotion of adequate sleep patterns coupled with circadian entrainment. We also discuss the physiological mechanisms underlying the beneficial effects of these lifestyle interventions on hypertension, which include not only the prevention of traditional risk factors (such as obesity and insulin resistance) and improvements in vascular health through an improved redox and inflammatory status, but also reduced sympathetic overactivation and non-traditional mechanisms such as increased secretion of myokines.

Ultrasound Therapy: Experiences and Perspectives for Regenerative Medicine.

Ultrasound has emerged as a novel tool for clinical applications, particularly in the context of regenerative medicine. Due to its unique physico-mechanical properties, low-intensity ultrasound (LIUS) has been approved for accelerated fracture healing and for the treatment of established non-union, but its utility has extended beyond tissue engineering to other fields, including cell regeneration. Cells and tissues respond to acoustic ultrasound by switching on genetic repair circuits, triggering a cascade of molecular signals that promote cell proliferation, adhesion, migration, differentiation, and extracellular matrix production. LIUS also induces angiogenesis and tissue regeneration and has anti-inflammatory and anti-degenerative effects. Accordingly, the potential application of ultrasound for tissue repair/regeneration has been tested in several studies as a stand-alone treatment and, more recently, as an adjunct to cell-based therapies. For example, ultrasound has been proposed to improve stem cell homing to target tissues due to its ability to create a transitional and local gradient of cytokines and chemokines. In this review, we provide an overview of the many applications of ultrasound in clinical medicine, with a focus on its value as an adjunct to cell-based interventions. Finally, we discuss the various preclinical and clinical studies that have investigated the potential of ultrasound for regenerative medicine.

Benefits of exercise and immunotherapy in a murine model of human non-small-cell lung carcinoma.

BACKGROUND: Lung cancer has the highest incidence and mortality rate in the world. One of the most promising new cancer therapies in recent years is immunotherapy, which is based on the blockade of immune checkpoints such as programmed cell death protein 1 (PD-1). Exercise training is beneficial to maintain and improve the quality of life of cancer patients, and it might also modulate the anti-tumoral efficiency of some chemotherapeutic agents. However, the potential of exercise combined with immunotherapy as a cancer therapy remains to be elucidated. Here, we examined the effects of exercise on tumor growth and its possible adjuvant effects when combined with anti-PD-1 immunotherapy (nivolumab) in a patient derived xenograft (PDX) model of non-small-cell lung carcinoma (NSCLC). METHODS: We generated a PDX model using NOD-SCID gamma mice with subcutaneous grafts from tumor tissue of a patient with NSCLC. Animals were randomly assigned to one of four groups: non-exercise + isotype control (n=5), exercise + isotype control (n=5), non-exercise + nivolumab (n=6) or exercise + nivolumab (n=6). The animals undertook an 8- week moderate-intensity training regimen (treadmill aerobic exercise and strength training). Immunotherapy (nivolumab) or an isotype control was administered 2 days/week, for 6 weeks. Several tumor growth and microenvironment parameters were measured after the intervention. RESULTS: Improvements in aerobic capacity and muscle strength (p=0.027 and p=0.005) were noted in exercised animals. Exercise alone reduced the tumor growth rate with respect to non-exercised mice (p=0.050). The double intervention (exercise + nivolumab) increased tumor necrosis and reduced apoptosis with respect to controls (p=0.026; p=0.030). All interventions achieved a reduction in proliferation compared with the control group (p=0.015, p=0.011, and p=0.011). Exercise alone increased myeloid tumor infiltrates (mostly neutrophils) with respect to the nivolumab only group (p=0.018). Finally, Vegf-a expression was higher in the nivolumab groups (in combination or not with exercise) than in exercise + isotype control group (p=0.045 and p=0.047, respectively). No other significant effects were found. CONCLUSIONS: Our results would suggest that aerobic and strength training should be studied as an adjuvant to cancer immunotherapy treatment.

Successful aging: insights from proteome analyses of healthy centenarians.

Healthy aging depends on a complex gene-environment network that is ultimately reflected in the expression of different proteins. We aimed to perform a comparative analysis of the plasma proteome of healthy centenarians (n=9, 5 women, age range 100-103 years) with a notably preserved ambulatory capacity (as a paradigm of 'successful' aging), and control individuals who died from a major age-related disease before the expected life expectancy (n=9, 5 women, age range: 67-81 years), and while having impaired ambulatory capacity (as a paradigm of 'unsuccessful' aging). We found that the expression of 49 proteins and 86 pathways differed between the two groups. Overall, healthy centenarians presented with distinct expression of proteins/pathways that reflect a healthy immune function, including a lower pro-inflammatory status (less 'inflammaging' and autoimmunity) and a preserved humoral immune response (increased B cell-mediated immune response). Compared with controls, healthy centenarians also presented with a higher expression of proteins involved in angiogenesis and related to enhanced intercellular junctions, as well as a lower expression of proteins involved in cardiovascular abnormalities. The identification of these proteins/pathways might provide new insights into the biological mechanisms underlying the paradigm of healthy aging.

Adipokines disrupt cardiac differentiation and cardiomyocyte survival.

BACKGROUND: The role of adipose tissue in the pathophysiology of cardiovascular disease remains a major subject of research. The objective of the present study was to dissect the molecular mechanisms that regulate the survival and differentiation of cardiac cells in an obese environment. MATERIAL AND METHODS: We isolated murine/human cardiac cells from adult hearts of control and obese mice/subjects and analyzed the communication between cardiac cells and adipocytes in vitro, as well as the effects on their main functions such as survival and differentiation. RESULTS: We found that the presence of visceral or subcutaneous adipocytes in the environment of cardiomyocytes or cardiac precursors provoked apoptosis or blocked differentiation, respectively, and these effects were mediated by secreted adipokines. Remarkably, cardiac precursors changed their fate and differentiated into mature adipocytes, contributing to the overall increase in adipose cell content. Inhibiting the adipokines TNF-α, visfatin, or HMGB1 could block the deleterious effects of adipokines on cardiac cells. CONCLUSIONS: Our findings demonstrate that mouse and human visceral adipose tissue contributes negatively to the homeostasis and regeneration of the heart. Moreover, our results suggest that blocking the action of certain adipokines might enhance cardiac differentiation and survival.

Functional Assays of Stem Cell Properties Derived from Different Niches.

It has been described that adult tissues contain mesenchymal stem cell populations. The specific areas where stem cells reside are known as niches. Crosstalk between cells and their niche is essential to maintain the correct functionality of stem cell. MSCs present a set of abilities such as migration, invasion, and angiogenic potentials, which make them ideal candidates for cell-based therapies. In order to test the regenerative capacity of these cells, we have described a methodology for the collection and for the evaluation of these mesenchymal precursors from different niches.

Unhealthy Stem Cells: When Health Conditions Upset Stem Cell Properties.

The stem cell field has grown very rapidly during the last decade, offering the promise of innovative therapies to treat disease. Different stem cell populations have been isolated from various human adult tissues, mainly from bone marrow and adipose tissue, but many other body tissues harbor a stem cell population. Adult tissue stem cells are invariably found in discrete microenvironments termed niches, where they play key roles in tissue homeostasis by enabling lifelong optimization of organ form and function. Some diseases are known to strike at the stem cell population, through alterations in their specific microenvironments, making them non-viable. Furthermore, it has been shown that a transformed stem cell population could prompt the development of certain cancers. This review focuses on the potential negative aspects of a range of diseases on the activity of stem cells and how their potential use in cell therapies may be affected.

Muscle molecular adaptations to endurance exercise training are conditioned by glycogen availability: a proteomics-based analysis in the McArdle mouse model.

KEY POINTS: Although they are unable to utilize muscle glycogen, McArdle mice adapt favourably to an individualized moderate-intensity endurance exercise training regime. Yet, they fail to reach the performance capacity of healthy mice with normal glycogen availability. There is a remarkable difference in the protein networks involved in muscle tissue adaptations to endurance exercise training in mice with and without glycogen availability. Indeed, endurance exercise training promoted the expression of only three proteins common to both McArdle and wild-type mice: LIMCH1, PARP1 and TIGD4. In turn, trained McArdle mice presented strong expression of mitogen-activated protein kinase 12 (MAPK12). ABSTRACT: McArdle's disease is an inborn disorder of skeletal muscle glycogen metabolism that results in blockade of glycogen breakdown due to mutations in the myophosphorylase gene. We recently developed a mouse model carrying the homozygous p.R50X common human mutation (McArdle mouse), facilitating the study of how glycogen availability affects muscle molecular adaptations to endurance exercise training. Using quantitative differential analysis by liquid chromatography with tandem mass spectrometry, we analysed the quadriceps muscle proteome of 16-week-old McArdle (n = 5) and wild-type (WT) (n = 4) mice previously subjected to 8 weeks' moderate-intensity treadmill training or to an equivalent control (no training) period. Protein networks enriched within the differentially expressed proteins with training in WT and McArdle mice were assessed by hypergeometric enrichment analysis. Whereas endurance exercise training improved the estimated maximal aerobic capacity of both WT and McArdle mice as compared with controls, it was ∼50% lower than normal in McArdle mice before and after training. We found a remarkable difference in the protein networks involved in muscle tissue adaptations induced by endurance exercise training with and without glycogen availability, and training induced the expression of only three proteins common to McArdle and WT mice: LIM and calponin homology domains-containing protein 1 (LIMCH1), poly (ADP-ribose) polymerase 1 (PARP1 - although the training effect was more marked in McArdle mice), and tigger transposable element derived 4 (TIGD4). Trained McArdle mice presented strong expression of mitogen-activated protein kinase 12 (MAPK12). Through an in-depth proteomic analysis, we provide mechanistic insight into how glycogen availability affects muscle protein signalling adaptations to endurance exercise training.

Importance and regulation of adult stem cell migration.

Cell migration is an essential process throughout the life of vertebrates, beginning during embryonic development and continuing throughout adulthood. Stem cells have an inherent ability to migrate, that is as important as their capacity for self-renewal and differentiation, enabling them to maintain tissue homoeostasis and mediate repair and regeneration. Adult stem cells reside in specific tissue niches, where they remain in a quiescent state until called upon and activated by tissue environmental signals. Cell migration is a highly regulated process that involves the integration of intrinsic signals from the niche and extrinsic factors. Studies using three-dimensional in vitro models have revealed the astonishing plasticity of cells in terms of the migration modes employed in response to changes in the microenvironment. These same properties can, however, be subverted during the development of some pathologies such as cancer. In this review, we describe the response of adult stem cells to migratory stimuli and the mechanisms by which they sense and transduce intracellular signals involved in migratory processes. Understanding the molecular events underlying migration may help develop therapeutic strategies for regenerative medicine and to treat diseases with a cell migration component.

Adipose stem cells from obese patients show specific differences in the metabolic regulators vitamin D and Gas5.

Adipose tissue is a significant source of mesenchymal stem cells for regenerative therapies; however, caution should be taken as their environmental niche can affect their functional properties. We have previously demonstrated the negative impact of obesity on the function of adipose-derived stem cells (ASCs). Here we have evaluated other possible properties and targets that are altered by obesity such as the recently described long non-coding molecule Gas5, which is involved in glucocorticoid resistance. Using ASCs isolated from obese (oASCs) and control subjects (cASCs), we have analyzed additional metabolic and inflammatory conditions that could be related with their impaired therapeutic potential and consequently their possible usefulness in the clinic.

Circulating leptin and adiponectin concentrations in healthy exceptional longevity.

People reaching exceptional longevity free of major age-related diseases represent the paradigm of successful aging. Adipose tissue function declines as we age, potentially resulting in changes of circulating adipokines (e.g., leptin and adiponectin). Here, we measured circulating levels of leptin and adiponectin in healthy centenarians (n=81; 100-104 years) and younger elderly controls (n=46; 70-80 years). Centenarians had significant higher serum levels of leptin compared with controls (p<0.001), whereas no significant differences were observed for adiponectin. Further research including also other blood variables will be needed to elucidate whether high leptin levels could serve as a hallmark of healthy exceptional longevity.

New insight on obesity and adipose-derived stem cells using comprehensive metabolomics.

Obesity affects the functional capability of adipose-derived stem cells (ASCs) and their effective use in regenerative medicine through mechanisms that are still poorly understood. In the present study we used a multiplatform [LC/MS, GC/MS and capillary electrophoresis/MS (CE/MS)], metabolomics, untargeted approach to investigate the metabolic alteration underlying the inequalities observed in obesity-derived ASCs. The metabolic fingerprint (metabolites within the cells) and footprint (metabolites secreted in the culture medium), from obesity- and non-obesity-derived ASCs of humans or mice, were characterized to provide valuable information. Metabolites associated with glycolysis, the tricarboxylic acid cycle, the pentose phosphate pathway and the polyol pathway were increased in the footprint of obesity-derived human ASCs, indicating alterations in carbohydrate metabolism, whereas, from the murine model, deep differences in lipid and amino acid catabolism were highlighted. Therefore, new insights on the ASCs' metabolome were provided that enhance our understanding of the processes underlying ASCs' stemness capacity and its relationship with obesity, in different cell models.