The Micro-RNA Cargo of Extracellular Vesicles Released by Human Adipose Tissue-Derived Mesenchymal Stem Cells Is Modified by Obesity

Renal ischemia alters the mRNA and miRNA profile of vasculature-related genes in scattered tubular-like cells from female pigs

Scattered tubular-like cells (STCs) are renal tubular cells that survive episodes of renal injury and acquire progenitor-like characteristics to repair other damaged kidney cells. STCs release proangiogenic factors in culture and induce microvascular proliferation in injured murine kidneys in vivo. Renovascular disease (RVD) compromises the reparative capacity of STCs, but the underlying mechanisms remain unknown. We hypothesized that RVD alters the expression of vasculature-related genes in swine STCs and impair their vasculoprotective properties. CD24+/CD133+ STCs were harvested from female pig kidneys after 10 wk of RVD or sham (n = 6 each), and the mRNA profiles of vasculature-related genes were analyzed using mRNA and microRNA seq (n = 3/group). STC expression of candidate differentially expressed (DE) genes and their capacity to induce human umbilical endothelial cells (HUVECs) to form tube-like networks were subsequently assessed in vitro before and after micro-RNA (miRNA) modulation (n = 6 each). mRNA-seq identified 67 upregulated and 42 downregulated vasculature-related genes in RVD-STCs. Four miRNAs were upregulated and 12 downregulated in RVD-STCs and found to target 31.3% to 40.5% of DE vasculature-related genes. Modulation in vitro of representative miRNAs decreased RVD-STC expression of anti-angiogenic and increased expression of proangiogenic target genes, respectively. Furthermore, this restored the ability of STCs to induce HUVEC tube formation on Matrigel that was impaired in RVD. Chronic renal ischemia alters the expression of vasculature-related genes in swine STCs, likely through posttranscriptional mechanisms, impairing their proangiogenic activity. These observations may contribute to develop novel approaches to preserve the reparative capacity of STCs in individuals with RVD.NEW & NOTEWORTHY The intrinsic reparative capacity of the adult mammalian kidney is restricted to the ability of scattered tubular-like cells (STCs) to repair damaged kidney cells. Our study provides evidence that chronic renal ischemia alters the mRNA/miRNA profile of angiogenic/vascular development genes of swine STCs, limiting their potential to repair injured tubular cells. Our observations may assist in developing new therapies to improve renal repair in individuals with chronic renal ischemia.

Mapping the landscape of childhood obesity: genomic insights and socioeconomic status in Indian school-going children

OBJECTIVE

Childhood obesity (OB) is influenced by complex gene-environmental interaction. While genetics of adult OB have been extensively studied, polygenic childhood OB in non-European populations is still underexplored. Furthermore, in a developing nation such as India, how the environmental component strongly modulated by the socioeconomic status (SES) shapes the genetic susceptibility is crucial to understand.

METHODS

A two-staged genome-wide association study (GWAS; N = 5673) and an independent exome-wide association study (ExWAS; N = 4963) were performed using a generalized linear model assuming additive effect to identify the common and rare genetic variants respectively associated with childhood OB. Rare-variant burden testing was also performed. We used the gene expression profiles and regulatory data from public databases to explain the novel associations. The implications of SES as a potential modifier of genetic susceptibility were evaluated.

RESULTS

GWAS identified novel associations in TCF7L2, IMMP2L, IPMK, CDC5L, SNTG1, and MX1, whereas ExWAS uncovered CNTN4, COQ4, TNFRSF10D, FLG-AS1, and BMP3. Both GWAS and ExWAS validated known associations in FTO and MC4R. Furthermore, rare-variant testing highlighted the role of 101 genes. We also observed that SES can modulate the inherent susceptibility to OB.

CONCLUSIONS

Our study identified genetic variants associated with childhood OB and highlighted the gene-environmental interaction in childhood OB.

The Impact of Obesity on Autophagy in Human Adipose-Derived Mesenchymal Stromal Cells

Mesenchymal stromal cells (MSCs) possess therapeutic properties, which can be blunted by obesity. Autophagy, a cellular recycling process, is essential for MSC function. We investigated the mechanisms by which obesity affects the properties of MSCs, with a focus on autophagy. Adipose tissue was obtained from kidney donors [body mass index (BMI) <30 kg/m2, non-obese] or individuals undergoing weight loss surgery (BMI ≥30 kg/m2, obese) for MSC harvesting (n = 11 each); samples were randomized to sequencing (seq; n = 5 each) or functional studies (n = 6 each). MSCs were sequenced to determine their epigenetic (5-hydroxymethylcytosine) and transcriptomic profiles across autophagy-related genes using hydroxymethylated DNA immunoprecipitation sequencing and mRNA-seq, respectively. Genes with shared trends in both datasets underwent Reverse Transcription Quantitative Polymerase Chain Reaction (RT-qPCR) validation. During functional studies, 2-h starvation was used to induce autophagy in vitro, enabling detection of changes in the protein expression of microtubule-associated protein 1A/1B-light chain-3 and in autophagic flux. Obesity amplified a starvation-induced reduction in autophagic flux in MSCs while promoting earlier generation of new autophagosomes during autophagy initiation. Integrated analysis of the two sequencing datasets revealed 124 differentially hydroxymethylated genes and 30 differentially expressed mRNAs. Among six overlapping autophagy-related genes, three exhibited same-direction trends. Of these, STX12 and SLC25A4 may be implicated in the impact of obesity on autophagic changes in MSCs. Therefore, human obesity may alter autophagy in adipose tissue-derived MSC, and thereby their metabolism and function.

Renovascular Disease and Mitochondrial Dysfunction in Human Mesenchymal Stem Cells

Key Points

Renovascular disease impairs the capacity of human adipose tissue–derived mesenchymal stem/stromal cells to repair ischemic murine kidneys. miR-378h modulated the capacity of renovascular disease adipose tissue–derived mesenchymal stem/stromal cells to repair ischemic kidneys in vivo .

Background

Renovascular disease leads to renal ischemia, hypertension, and eventual kidney failure. Autologous transplantation of adipose tissue–derived mesenchymal stem/stromal cells (MSCs) improves perfusion and oxygenation in stenotic human kidneys, but associated atherosclerosis and hypertension might blunt their effectiveness. We hypothesized that renovascular disease alters the human MSC transcriptome and impairs their reparative potency.

Methods

MSCs were harvested from subcutaneous abdominal fat of patients with renovascular disease and healthy volunteers (n =3 each), characterized and subsequently injected (5×105/200 μ l) into mice 2 weeks after renal artery stenosis or sham surgery (n =6/group). Two weeks later, mice underwent imaging and tissue studies. MSCs from healthy volunteers and in those with renovascular disease were also characterized by mRNA/microRNA (miRNA) sequencing. Based on these, MSC proliferation and mitochondrial damage were assessed in vitro before and after miRNA modulation and in vivo in additional renal artery stenosis mice administered with MSCs from renovascular disease pretreated with miR-378h mimic (n =5) or inhibitor (n =4).

Results

MSCs engrafted in stenotic mouse kidneys. Healthy volunteer MSCs (but not renovascular disease MSCs) decreased BP, improved serum creatinine levels and stenotic-kidney cortical perfusion and oxygenation, and attenuated peritubular capillary loss, tubular injury, and fibrosis. Genes upregulated in renovascular disease MSCs versus healthy volunteer MSCs were mostly implicated in transcription and cell proliferation, whereas those downregulated encoded mainly mitochondrial proteins. Upregulated miRNAs, including miR-378h, primarily target nuclear-encoded mitochondrial genes, whereas downregulated miRNAs mainly target genes implicated in transcription and cell proliferation. MSC proliferation was similar, but their mitochondrial structure and reparative function both in vivo and in vitro improved after miR-378h inhibition.

Conclusions

Renovascular disease impaired the reparative capacity of human MSCs, possibly by dysregulating miR-378h that targets mitochondrial genes.

Podcast

This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/JASN/2024_08_21_ASN0000000000000440.mp3

Apoptotic vesicles rescue impaired mesenchymal stem cells and their therapeutic capacity for osteoporosis by restoring miR-145a-5p deficiency

Apoptotic vesicles (apoVs) play a vital role in various physiological and pathological conditions. However, we have yet to fully understand their precise biological effects in rescuing impaired mesenchymal stem cells (MSCs). Here, we proved that systemic infusion of MSCs derived from wild-type (WT) mice rather than from ovariectomized (OVX) mice effectively improved the osteopenia phenotype and rescued the impaired recipient MSCs in osteoporotic mice. Meanwhile, apoVs derived from WT MSCs (WT apoVs) instead of OVX apoVs efficiently restored the impaired biological function of OVX MSCs and their ability to improve osteoporosis. Mechanistically, the reduced miR-145a-5p expression hindered the osteogenic differentiation and immunomodulatory capacity of OVX MSCs by affecting the TGF-β/Smad 2/3-Wnt/β-catenin signaling axis, resulting in the development of osteoporosis. WT apoVs directly transferred miR-145a-5p to OVX MSCs, which were then reused to restore their impaired biological functions. The differential expression of miR-145a-5p is responsible for the distinct efficacy between the two types of apoVs. Overall, our findings unveil the remarkable potential of apoVs, as a novel nongenetic engineering approach, in rescuing the biological function and therapeutic capability of MSCs derived from patients. This discovery offers a new avenue for exploring apoVs-based stem cell engineering and expands the application scope of stem cell therapy, contributing to the maintenance of bone homeostasis through a previously unrecognized mechanism.

Apoptotic vesicles rescue impaired mesenchymal stem cells and their therapeutic capacity for osteoporosis by restoring miR-145a-5p deficiency

Apoptotic vesicles (apoVs) play a vital role in various pathological conditions; however, we have yet to fully understand their precise biological effects in rescuing impaired mesenchymal stem cells (MSCs) and regulating tissue homeostasis. Here, we proved that systemic infusion of bone marrow MSCs derived from wild-type (WT) mice effectively improved the osteopenia phenotype and hyperimmune state in ovariectomized (OVX) mice. Importantly, the WT MSCs rescued the impairment of OVX MSCs both in vivo and in vitro, whereas OVX MSCs did not show the same efficacy. Interestingly, treatment with apoVs derived from WT MSCs (WT apoVs) restored the impaired biological function of OVX MSCs and their ability to improve osteoporosis. This effect was not observed with OVX MSCs-derived apoVs (OVX apoVs) treatment. Mechanistically, the reduced miR-145a-5p expression hindered the osteogenic differentiation and immunomodulatory capacity of OVX MSCs by affecting the TGF-β/Smad 2/3-Wnt/β-catenin signaling axis, resulting in the development of osteoporosis. WT apoVs directly transferred miR-145a-5p to OVX MSCs, which were then reused to restore their impaired biological functions. Conversely, treatment with OVX apoVs did not produce significant effects due to their limited expression of miR-145a-5p. Overall, our findings unveil the remarkable potential of apoVs in rescuing the biological function and therapeutic capability of MSCs derived from individuals with diseases. This discovery offers a new avenue for exploring apoVs-based MSC engineering and expands the application scope of stem cell therapy, contributing to the maintenance of bone homeostasis through a previously unrecognized mechanism.

Understanding molecular characteristics of extracellular vesicles derived from different types of mesenchymal stem cells for therapeutic translation

Mesenchymal stem cells (MSCs) have been studied for decades as candidates for cellular therapy, and their secretome, including secreted extracellular vesicles (EVs), has been identified to contribute significantly to regenerative and reparative functions. Emerging evidence has suggested that MSC-EVs alone, could be used as therapeutics that emulate the biological function of MSCs. However, just as with MSCs, MSC-EVs have been shown to vary in composition, depending on the tissue source of the MSCs as well as the protocols employed in culturing the MSCs and obtaining the EVs. Therefore, the importance of careful choice of cell sources and culture environments is receiving increasing attention. Many factors contribute to the therapeutic potential of MSC-EVs, including the source tissue, isolation technique, and culturing conditions. This review illustrates the molecular landscape of EVs derived from different types of MSC cells along with culture strategies. A thorough analysis of publicly available omic datasets was performed to advance the precision understanding of MSC-EVs with unique tissue source-dependent molecular characteristics. The tissue-specific protein and miRNA-driven Reactome ontology analysis was used to reveal distinct patterns of top Reactome ontology pathways across adipose, bone marrow, and umbilical MSC-EVs. Moreover, a meta-analysis assisted by an AI technique was used to analyze the published literature, providing insights into the therapeutic translation of MSC-EVs based on their source tissues.

Obesity-driven mitochondrial dysfunction in human adipose tissue-derived mesenchymal stem/stromal cells involves epigenetic changes

Obesity exacerbates tissue degeneration and compromises the integrity and reparative potential of mesenchymal stem/stromal cells (MSCs), but the underlying mechanisms have not been sufficiently elucidated. Mitochondria modulate the viability, plasticity, proliferative capacity, and differentiation potential of MSCs. We hypothesized that alterations in the 5-hydroxymethylcytosine (5hmC) profile of mitochondria-related genes may mediate obesity-driven dysfunction of human adipose-derived MSCs. MSCs were harvested from abdominal subcutaneous fat of obese and age/sex-matched non-obese subjects (n = 5 each). The 5hmC profile and expression of nuclear-encoded mitochondrial genes were examined by hydroxymethylated DNA immunoprecipitation sequencing (h MeDIP-seq) and mRNA-seq, respectively. MSC mitochondrial structure (electron microscopy) and function, metabolomics, proliferation, and neurogenic differentiation were evaluated in vitro, before and after epigenetic modulation. hMeDIP-seq identified 99 peaks of hyper-hydroxymethylation and 150 peaks of hypo-hydroxymethylation in nuclear-encoded mitochondrial genes from Obese- versus Non-obese-MSCs. Integrated hMeDIP-seq/mRNA-seq analysis identified a select group of overlapping (altered levels of both 5hmC and mRNA) nuclear-encoded mitochondrial genes involved in ATP production, redox activity, cell proliferation, migration, fatty acid metabolism, and neuronal development. Furthermore, Obese-MSCs exhibited decreased mitochondrial matrix density, membrane potential, and levels of fatty acid metabolites, increased superoxide production, and impaired neuronal differentiation, which improved with epigenetic modulation. Obesity elicits epigenetic changes in mitochondria-related genes in human adipose-derived MSCs, accompanied by structural and functional changes in their mitochondria and impaired fatty acid metabolism and neurogenic differentiation capacity. These observations may assist in developing novel therapies to preserve the potential of MSCs for tissue repair and regeneration in obese individuals.

Challenges and opportunities in obesity: the role of adipocytes during tissue fibrosis

Obesity is a chronic disease that affects the energy balance of the whole body. In addition to increasing fat mass, tissue fibrosis occurred in white adipose tissue in obese condition. Fibrosis is the over-activation of fibroblasts leading to excessive accumulation of extracellular matrix, which could be caused by various factors, including the status of adipocytes. The morphology of adipocytes responds rapidly and dynamically to nutrient fluctuations. Adaptive hypertrophy of normal adipocytes protects peripheral organs from damage from lipotoxicity. However, the biological behavior of hypertrophic adipocytes in chronic obesity is abnormally altered. Adipocytes lead to fibrotic remodeling of the extracellular matrix by inducing unresolved chronic inflammation, persistent hypoxia, and increasing myofibroblast numbers. Moreover, adipocyte-induced fibrosis not only restricts the flexible expansion and contraction of adipose tissue but also initiates the development of various diseases through cellular autonomic and paracrine effects. Regarding anti-fibrotic therapy, dysregulated intracellular signaling and epigenetic changes represent potential candidate targets. Thus, modulation of adipocytes may provide potential therapeutic avenues for reversing pathological fibrosis in adipose tissue and achieving the anti-obesity purpose.

Next-Cell Hypothesis: Mechanism of Obesity-Associated Carcinogenesis

Higher body fat content is related to a higher risk of mortality, and obesity-related cancer represents approximately 40% of all cancer patients diagnosed each year. Furthermore, epigenetic mechanisms are involved in cellular metabolic memory and can determine one's predisposition to being overweight. Low-grade chronic inflammation, a well-established characteristic of obesity, is a central component of tumor development and progression. Cancer-associated adipocytes (CAA), which enhance inflammation- and metastasis-related gene sets within the cancer microenvironment, have pro-tumoral effects. Adipose tissue is a major source of the exosomal micro ribonucleic acids (miRNAs), which modulate pathways involved in the development of obesity and obesity-related comorbidities. Owing to their composition of cargo, exosomes can activate receptors at the target cell or transfer molecules to the target cells and thereby change the phenotype of these cells. Exosomes that are released into the extracellular environment are internalized with their cargo by neighboring cells. The tumor-secreted exosomes promote organ-specific metastasis of tumor cells that normally lack the capacity to metastasize to a specific organ. Therefore, the communication between neighboring cells via exosomes is defined as the "next-cell hypothesis." The reciprocal interaction between the adipocyte and tumor cell is realized through the adipocyte-derived exosomal miRNAs and tumor cell-derived oncogenic miRNAs. The cargo molecules of adipocyte-derived exosomes are important messengers for intercellular communication involved in metabolic responses and have very specific signatures that direct the metabolic activity of target cells. RNA-induced silencing regulates gene expression through various mechanisms. Destabilization of DICER enzyme, which catalyzes the conversion of primary miRNA (pri-miRNA) to precursor miRNA (pre-miRNA), is an important checkpoint in cancer development and progression. Interestingly, adipose tissue in obesity and tumors share similar pathogenic features, and the local hypoxia progress in both. While hypoxia in obesity leads to the adipocyte dysfunction and metabolic abnormalities, in obesity-related cancer cases, it is associated with worsened prognosis, increased metastatic potential, and resistance to chemotherapy. Notch-interleukin-1 (IL-1)-Leptin crosstalk outcome is referred to as "NILCO effect." In this chapter, obesity-related cancer development is discussed in the context of "next-cell hypothesis," miRNA biogenesis, and "NILCO effect."

Modulation of MicroRNAs and Exosomal MicroRNAs after Dietary Interventions for Obesity and Insulin Resistance: A Narrative Review

MicroRNAs (miRNAs) are small noncoding RNAs approximately 22 nucleotides in length. Their main function is to regulate gene expression at the posttranscriptional level by inhibiting the translation of messenger RNAs (mRNAs). miRNAs originate in the cell nucleus from specific genes, where they can perform their function. However, they can also be found in serum, plasma, or other body fluids travelling within vesicles called exosomes and/or bound to proteins or other particles such as lipoproteins. miRNAs can form complexes outside the cell where they are synthesized, mediating paracrine and endocrine communication between different tissues. In this way, they can modulate the gene expression and function of distal cells. It is known that the expression of miRNAs can be affected by multiple factors, such as the nutritional or pathological state of the individual, or even in conditions such as obesity, insulin resistance, or after any dietary intervention. In this review, we will analyse miRNAs whose expression and circulation are affected in conditions of obesity and insulin resistance, as well as the changes generated after a dietary intervention, with the purpose of identifying new possible biomarkers of early response to nutritional treatment in these conditions.

Breast adipose tissue-derived extracellular vesicles from obese women alter tumor cell metabolism

Breast adipose tissue is an important contributor to the obesity-breast cancer link. Extracellular vesicles (EVs) are nanosized particles containing selective cargo, such as miRNAs, that act locally or circulate to distant sites to modulate target cell functions. Here, we find that long-term education of breast cancer cells with EVs obtained from breast adipose tissue of women who are overweight or obese (O-EVs) results in increased proliferation. RNA-seq analysis of O-EV-educated cells demonstrates increased expression of genes involved in oxidative phosphorylation, such as ATP synthase and NADH: ubiquinone oxidoreductase. O-EVs increase respiratory complex protein expression, mitochondrial density, and mitochondrial respiration in tumor cells. The mitochondrial complex I inhibitor metformin reverses O-EV-induced cell proliferation. Several miRNAs-miR-155-5p, miR-10a-3p, and miR-30a-3p-which promote mitochondrial respiration and proliferation, are enriched in O-EVs relative to EVs from lean women. O-EV-induced proliferation and mitochondrial activity are associated with stimulation of the Akt/mTOR/P70S6K pathway, and are reversed upon silencing of P70S6K. This study reveals a new facet of the obesity-breast cancer link with human breast adipose tissue-derived EVs causing metabolic reprogramming of breast cancer cells.

Obesity Blunts the Effect of Mesenchymal Stem Cell-Derived Extracellular Vesicles

Introduction

Mesenchymal stem/stromal cell-derived extracellular vesicles (MSC-EVs) are paracrine vectors with therapeutic functions comparable to their parent cells. However, it remains unclear if donor obesity affects their therapeutic functions. We tested the hypothesis that the curative effect of human adipose tissue-derived MSC-EVs (A-MSC-EVs) is blunted by obesity.

Methods

MSC-EVs were isolated by ultracentrifugation from mesenchymal stem/stromal cells (MSCs) collected from abdominal subcutaneous fat of obese and lean human subjects (obese and lean-MSC-EVs, respectively) and injected into the aorta of mice 2 weeks after renal artery stenosis (RAS) induction. Magnetic resonance imaging studies were conducted 2 weeks after MSC-EVs delivery to determine renal function. The effect of MSC-EVs on tissue injury was assessed by histology and gene expression of inflammatory factors, including interleukin (IL)-1β, IL-6, monocyte chemotactic protein-1 (MCP-1), and tumor necrosis factor alpha (TNF-α). Oxidative damage, macrophage infiltration, plasma renin, and hypoxia inducible factor-1α (HIF-1α) were also assessed.

Results

Tracking showed that MSC-EVs localized in the kidney tissue, including glomeruli and tubules. All MSC-EVs decreased systolic blood pressure (SBP) and plasma renin and improved the poststenotic kidney (STK) volume, but obese-MSC-EVs were less effective than lean-MSC-EVs in improving medullary hypoxia, fibrosis, and tubular injury. Lean-MSC-EVs decreased inflammation, whereas obesity attenuated this effect. Only lean-MSC-EVs decreased STK cortical HIF-1α expression.

Conclusion

Obesity attenuates the antihypoxia, antifibrosis, antiinflammation, and tubular repair functions of human MSC-EVs in chronic ischemic kidney disease. These observations may have implications for the self-repair potency of obese subjects and for the use of autologous MSC-EVs in regenerative medicine.

Mechanisms of bariatric surgery for weight loss and diabetes remission

Obesity and type 2 diabetes(T2D) lead to defects in intestinal hormones secretion, abnormalities in the composition of bile acids (BAs), increased systemic and adipose tissue inflammation, defects of branched-chain amino acids (BCAAs) catabolism, and dysbiosis of gut microbiota. Bariatric surgery (BS) has been shown to be highly effective in the treatment of obesity and T2D, which allows us to view BS not simply as weight-loss surgery but as a means of alleviating obesity and its comorbidities, especially T2D. In recent years, accumulating studies have focused on the mechanisms of BS to find out which metabolic parameters are affected by BS through which pathways, such as which hormones and inflammatory processes are altered. The literatures are saturated with the role of intestinal hormones and the gut-brain axis formed by their interaction with neural networks in the remission of obesity and T2D following BS. In addition, BAs, gut microbiota and other factors are also involved in these benefits after BS. The interaction of these factors makes the mechanisms of metabolic improvement induced by BS more complicated. To date, we do not fully understand the exact mechanisms of the metabolic alterations induced by BS and its impact on the disease process of T2D itself. This review summarizes the changes of intestinal hormones, BAs, BCAAs, gut microbiota, signaling proteins, growth differentiation factor 15, exosomes, adipose tissue, brain function, and food preferences after BS, so as to fully understand the actual working mechanisms of BS and provide nonsurgical therapeutic strategies for obesity and T2D.

Obesity blunts amelioration of cardiac hypertrophy and fibrosis by human mesenchymal stem/stromal cell-derived extracellular vesicles

Renovascular hypertension (RVH) can induce cardiac damage that is reversible using adipose tissue-derived mesenchymal stromal/stem cells (A-MSCs). However, A-MSCs isolated from patients with obesity are less effective than lean-A-MSC in blunting hypertensive cardiomyopathy in mice with RVH. We tested the hypothesis that this impairment extends to their obese A-MSC-extracellular vesicles (EVs) progeny. MSCs were harvested from the subcutaneous fat of obese and lean human subjects, and their EVs were collected and injected into the aorta of mice 2 wk after renal artery stenosis or sham surgery. Cardiac left ventricular (LV) function was studied with MRI 2 wk later, and myocardial tissue ex vivo. Blood pressure, LV myocardial wall thickness, mass, and fibrosis that were elevated in RVH mice were suppressed only by lean EVs. Hence, human A-MSC-derived lean EVs are more effective than obese EVs in blunting hypertensive cardiac injury in RVH mice. These observations highlight impaired paracrine repair potency of endogenous MSCs in patients with obesity.NEW & NOTEWORTHY Injection of A-MSC-derived EVs harvested from patients who are lean can resolve myocardial injury in mice with experimental renovascular hypertension more effectively than A-MSC-derived EVs from patients with obesity. These observations underscore and might have important ramifications for the self-healing capacity of patients with obesity and for the use of autologous EVs as a regenerative tool.

Role of Epicardial Adipose Tissue Secretome on Cardiovascular Diseases

Obesity and insulin resistance are associated with the inflamed and defective adipose tissue (AT) phenotype, and are established risk factors for cardiovascular diseases (CVDs). Extracellular vesicles (EVs) are a heterogeneous group of cell-derived lipid membrane vesicles involved in the onset and development of many pathologies, including insulin resistance, diabetes, and CVDs. The inflammation associated with overweight and obesity triggers the transition of the AT secretome from healthy to pathological, with a consequent increased expression of pro-inflammatory mediators. Epicardial adipose tissue (EAT) is a specialized fat depot that surrounds the heart, in direct contact with the myocardium. Recently, the role of EAT in regulating the physiopathology of many heart diseases has been increasingly explored. In particular, the EAT phenotype and derived EVs have been associated with the onset and exacerbation of CVDs. In this review, we will focus on the role of the AT secretome in the case of CVDs, and will discuss the beneficial effects of EVs released by AT as promising therapeutic candidates.

The Potential Role of Exosomes in Aesthetic Plastic Surgery: A Review of Current Literature

Despite an increasing surge of exosome use throughout the aesthetic arena, a paucity of published exosome-based literature exists. Exosomes are membrane-bound extracellular vesicles derived from various cell types, exerting effects via intercellular communication and regulation of several signaling pathways. The purpose of this review was to summarize published articles elucidating mechanisms and potential applications, report available products and clinical techniques, and prompt further investigation of this emerging treatment within the plastic surgery community.

Methods

A literature review was performed using PubMed with keywords exosomes, secretomes, extracellular vesicles, plastic surgery, skin rejuvenation, scar revision, hair growth, body contouring, and breast augmentation. Publications from 2010 to 2021 were analyzed for relevance and level of evidence. A Google search identified exosome distributors, where manufacturing/procurement details, price, efficacy, and clinical indications for use were obtained by direct contact and summarized in table format.

Results

Exosomes are currently derived from bone marrow, placental, adipose, and umbilical cord tissue. Laboratory-based exosome studies demonstrate enhanced outcomes in skin rejuvenation, scar revision, hair restoration, and fat graft survival on the macro and micro levels. Clinical studies are limited to anecdotal results. Prices vary considerably from $60 to nearly $5000 based on company, source tissue, and exosome concentration. No exosome-based products are currently Food and Drug Administration-approved.

Conclusions

Administered alone or as an adjunct, current reports show promise in several areas of aesthetic plastic surgery. However, ongoing investigation is warranted to further delineate concentration, application, safety profile, and overall outcome efficacy.

Obesity and dyslipidemia are associated with partially reversible modifications to DNA hydroxymethylation of apoptosis- and senescence-related genes in swine adipose-derived mesenchymal stem/stromal cells

BACKGROUND

Obesity dysregulates key biological processes underlying the functional homeostasis, fate decisions, and reparative potential of mesenchymal stem/stromal cells (MSCs). Mechanisms directing obesity-induced phenotypic alterations in MSCs remain unclear, but emerging drivers include dynamic modification of epigenetic marks, like 5-hydroxymethylcytosine (5hmC). We hypothesized that obesity and cardiovascular risk factors induce functionally relevant, locus-specific changes in 5hmC of swine adipose-derived MSCs and evaluated their reversibility using an epigenetic modulator, vitamin-C.

METHODS

Female domestic pigs were fed a 16-week Lean or Obese diet (n = 6 each). MSCs were harvested from subcutaneous adipose tissue, and 5hmC profiles were examined through hydroxymethylated DNA immunoprecipitation sequencing (hMeDIP-seq) followed by an integrative (hMeDIP and mRNA sequencing) gene set enrichment analysis. For clinical context, we compared 5hmC profiles of adipose tissue-derived human MSCs harvested from patients with obesity and healthy controls.

RESULTS

hMeDIP-seq revealed 467 hyper- (fold change ≥ 1.4; p-value ≤ 0.05) and 591 hypo- (fold change ≤ 0.7; p-value ≤ 0.05) hydroxymethylated loci in swine Obese- versus Lean-MSCs. Integrative hMeDIP-seq/mRNA-seq analysis identified overlapping dysregulated gene sets and discrete differentially hydroxymethylated loci with functions related to apoptosis, cell proliferation, and senescence. These 5hmC changes were associated with increased senescence in cultured MSCs (p16/CDKN2A immunoreactivity, senescence-associated β-galactosidase [SA-β-Gal] staining), were partly reversed in swine Obese-MSCs treated with vitamin-C, and shared common pathways with 5hmC changes in human Obese-MSCs.

CONCLUSIONS

Obesity and dyslipidemia are associated with dysregulated DNA hydroxymethylation of apoptosis- and senescence-related genes in swine and human MSCs, potentially affecting cell vitality and regenerative functions. Vitamin-C may mediate reprogramming of this altered epigenomic landscape, providing a potential strategy to improve the success of autologous MSC transplantation in obese patients.

Adipose Tissue-Derived Stem Cell Extracellular Vesicles Suppress Glioblastoma Proliferation, Invasiveness and Angiogenesis

Extracellular vesicles (EVs) are attractive anticancer drug delivery candidates as they confer several fundamental properties, such as low immunogenicity and the ability to cross biological barriers. Mesenchymal stem cells (MSCs) are convenient producers for high EV yields, and patient-derived adipose tissue MSC-EVs could serve as personalised carriers. However, MSC-EV applications raise critical concerns as their natural cargo can affect tumour progression in both inducing and suppressing ways. In this study, we investigated the effect of adipose tissue-derived mesenchymal stem cell EVs (ASC-EVs) on several glioblastoma (GBM) cell lines to define their applicability for anticancer therapies. ASC-EVs were isolated from a cell-conditioned medium and characterised by size and specific markers. The internalisation of fluorescently labelled ASC-EVs by human GBM cells HROG36, U87 MG, and T98G was evaluated by fluorescent microscopy. Changes in GBM cell proliferation after ASC-EV application were determined by the metabolic PrestoBlue assay. Expression alterations in genes responsible for cell adhesion, proliferation, migration, and angiogenesis were evaluated by quantitative real-time PCR. ASC-EV effects on tumour invasiveness and neoangiogenesis in ovo were analysed on the chicken embryo chorioallantoic membrane model (CAM). ASC-EV treatment reduced GBM proliferation in vitro and significantly downregulated invasiveness-related genes ITGα5 (in T98G and HROG63) and ITGβ3 (in HROG36) and the vascularisation-inducing gene KDR (in all GBM lines). Additionally, an approximate 65% reduction in the GBM invasion rate was observed in CAM after ASC-EV treatment. Our study indicates that ASC-EVs possess antitumour properties, reducing GBM cell proliferation and invasiveness, and can be applied as anticancer therapeutics and medicine carriers.

Analysis of circulating extracellular vesicle derived microRNAs in breast cancer patients with obesity: a potential role for Let-7a

BACKGROUND

The incidence of obesity, a known risk factor for several metabolic and chronic diseases, including numerous malignancies, has risen sharply in the world. Various clinical studies demonstrate that excessive Body Mass Index (BMI) may worsen the incidence, prognosis, and mortality rates of breast cancer. Thus, understanding the link tying up obesity and breast cancer onset and progression is critically important, as it can impact patients' survival and quality of life. Recently, circulating extracellular vesicle (EV) derived miRNAs have attracted much attention for their diagnostic, prognostic and therapeutic potential in oncology research. Although the potential role of EV-derived miRNAs in the early detection of breast cancer has been repeatedly mentioned, screening of miRNAs packaged within serum EVs has not yet been reported in patients with obesity.

METHODS

Circulating EVs were isolated from normal weight (NW), and overweight/obese (OW/Ob) breast cancer patients and characterized by Transmission Electron Microscopy (TEM), Nanoparticle Tracking Analysis (NTA), and protein marker expression. Evaluation of EV-associated miRNAs was conducted in a screening (RNA-seq) and a validation (qRT-PCR) cohort. Bioinformatic analysis was performed to uncover significantly enriched biological processes, molecular functions and pathways. ROC and Kaplain-Meier survival analyses were used for clinical significance.

RESULTS

Comparison of serum EV-derived miRNAs from NW and OW/Ob patients detected seven differentially expressed miRNAs (let-7a-5p, miR-122-5p, miR-30d-5p, miR-126-3p, miR-27b-3p, miR-4772-3p, and miR-10a-5p) in the screening cohort. GO analysis revealed the enrichment of protein phosphorylation, intracellular signal transduction, signal transduction, and vesicle-mediated transport among the top biological processes. In addition, the target genes were significantly enriched in pathways related to PI3K/Akt, growth hormones, and insulin signalings, which are all involved in obesity-related diseases and/or breast cancer progression. In the validation cohort, qRT-PCR confirmed a significant down-regulation of EV-derived let-7a in the serum of OW/Ob breast cancer patients compared to NW patients. Let-7a levels also exhibited a negative correlation with BMI values. Importantly, decreased let-7a miRNA expression was associated with higher tumor grade and poor survival in patients with breast cancer.

CONCLUSION

These results suggest that serum-EV derived miRNAs may reflect a differential profile in relation to a patient's BMI, which, once validated in larger cohorts of patients, could provide insights into novel specific biomarkers and innovative targets to prevent the progression of obesity-mediated breast cancer.

Breast adipose tissue-derived extracellular vesicles from women with obesity stimulate mitochondrial-induced dysregulated tumor cell metabolism

Breast adipose tissue is an important contributor to the obesity-breast cancer link. Dysregulated cell metabolism is now an accepted hallmark of cancer. Extracellular vesicles (EVs) are nanosized particles containing selective cargo, such as miRNAs, that act locally or circulate to distant sites to modulate target cell functions. Here, we found that long-term education of breast cancer cells (MCF7, T47D) with EVs from breast adipose tissue of women who are overweight or obese (O-EVs) leads to sustained increased proliferative potential. RNA-Seq of O-EV-educated cells demonstrates increased expression of genes, such as ATP synthase and NADH: ubiquinone oxidoreductase, involved in oxidative phosphorylation. O-EVs increase respiratory complex protein expression, mitochondrial density, and mitochondrial respiration in tumor cells. Mitochondrial complex I inhibitor, metformin, reverses O-EV-induced cell proliferation. Several miRNAs, miR-155-5p, miR-10a-3p, and miR-30a-3p, which promote mitochondrial respiration and proliferation, are enriched in O-EVs relative to EVs from lean women. O-EV-induced proliferation and mitochondrial activity are associated with stimulation of the Akt/mTOR/P70S6K pathway, and are reversed upon silencing of P70S6K. This study reveals a new facet of the obesity-breast cancer link with human breast adipose tissue-derived EVs causing the metabolic reprogramming of ER+ breast cancer cells.

Searching for the Optimal Donor for Allogenic Adipose-Derived Stem Cells: A Comprehensive Review

Adipose-derived stem cells comprise several clinically beneficial qualities that have been explored in basic research and have motivated several clinical studies with promising results. After being approved in the European Union, UK, Switzerland, Israel, and Japan, allogeneic adipose-derived stem cells (darvadstrocel) have been recently granted a regenerative medicine advanced therapy (RMAT) designation by US FDA for complex perianal fistulas in adults with Crohn's disease. This huge scientific step is likely to impact the future spread of the indications of allogeneic adipose-derived stem cell applications. The current knowledge on adipose stem cell harvest describes quantitative and qualitative differences that could be influenced by different donor conditions and donor sites. In this comprehensive review, we summarize the current knowledge on the topic and propose donor profiles that could provide the optimal initial quality of this living drug, as a starting point for further applications and studies in different pathological conditions.

Cardiac micro-RNA and transcriptomic profile of a novel swine model of chronic kidney disease and left ventricular diastolic dysfunction

Chronic kidney disease (CKD) is an independent risk factor for the development of heart failure, but the underlying mechanisms remain unknown. Using a novel translational swine model of CKD and cardiac dysfunction, we hypothesize that CKD alters the cardiac miRNA and transcriptomic profile that associate with cardiac remodeling and metabolic processes implicated in the development of left ventricular diastolic dysfunction (CKD-LVDD). CKD-LVDD and normal control pigs (n = 6 each) were studied for 14 wk. Renal and cardiac hemodynamics were quantified by multidetector CT and echocardiography. In randomly selected pigs (n = 3/group), cardiac miRNA- and mRNA-sequencing (seq) was performed, validated (qPCR), and followed by confirmatory ex vivo studies. Differential expression analysis identified nine miRNAs and 125 mRNAs upregulated and 17 miRNAs and 172 mRNAs downregulated [fold-change ≥ 2, and false discovery rate (FDR) ≤ 0.05] in CKD-LVDD versus normal controls. Integrated miRNA-/mRNA-seq analysis identified 71 overlappings downregulated mRNA targets of miRNAs upregulated, and 39 overlappings upregulated mRNA targets of miRNAs downregulated in CKD-LVDD versus controls. Functional analysis showed that these genes were primarily implicated in processes associated with cardiac remodeling, including ubiquitination, ATP and fatty acid synthesis, and extracellular matrix remodeling. In agreement, hearts of CKD-LVDD pigs exhibited abnormal diastolic relaxation, mitochondrial injury, moderate LV fibrosis, and myocardial lipid accumulation. Our work comprehensively characterizes the cardiac micro-RNA and transcriptomic profile of a translational model of CKD-LVDD. Our data may set the foundation for new targeted studies to further elucidate LVDD pathophysiology and assist to develop therapeutic interventions.NEW & NOTEWORTHY Chronic kidney disease (CKD) is a progressive disorder in which more than 50% of deaths are attributed to cardiovascular disease. Using a swine model of CKD that develops left ventricular dysfunction (CKD-LVDD), we characterize the cardiac micro-RNA and transcriptomic profile, identifying dysregulated genes associated with cardiac remodeling and fatty acid metabolism that might be post-transcriptionally regulated early in the disease. These findings pinpointed pathological pathways that may open new avenues toward therapeutic research to reduce cardiovascular morbidity in CKD.

Extracellular Vesicles as Theranostic Tools in Kidney Disease

Extracellular vesicles are important vectors for cell-cell communication and show potential value for diagnosis and treatment of kidney diseases. The pathologic diagnosis of kidney diseases relies on kidney biopsy, whereas collection of extracellular vesicles from urine or circulating blood may constitute a less invasive diagnostic tool. In particular, urinary extracellular vesicles released mainly from resident kidney cells might provide an alternative tool for detection of kidney injury. Because extracellular vesicles mirror many features of their parent cells, cargoes of several populations of urinary extracellular vesicles are promising biomarkers for disease processes, like diabetic kidney disease, kidney transplant, and lupus nephritis. Contrarily, extracellular vesicles derived from reparative cells, such as mesenchymal stem cells, tubular epithelial progenitor cells, and human umbilical cord blood represent promising regenerative tools for treatment of kidney diseases. Furthermore, induced pluripotent stem cells-derived and engineered extracellular vesicles are being developed for specific applications for the kidney. Nevertheless, some assumptions regarding the specificity and immunogenicity of extracellular vesicles remain to be established. This review focuses on the utility of extracellular vesicles as therapeutic and diagnostic (theranostic) tools in kidney diseases and future directions for studies.

Adipose Tissue-Derived Mesenchymal Stromal/Stem Cells, Obesity and the Tumor Microenvironment of Breast Cancer

Breast cancer is the most frequently diagnosed cancer and a common cause of cancer-related death in women. It is well recognized that obesity is associated with an enhanced risk of more aggressive breast cancer as well as reduced patient survival. Adipose tissue is the major microenvironment of breast cancer. Obesity changes the composition, structure, and function of adipose tissue, which is associated with inflammation and metabolic dysfunction. Interestingly, adipose tissue is rich in ASCs/MSCs, and obesity alters the properties and functions of these cells. As a key component of the mammary stroma, ASCs play essential roles in the breast cancer microenvironment. The crosstalk between ASCs and breast cancer cells is multilateral and can occur both directly through cell-cell contact and indirectly via the secretome released by ASC/MSC, which is considered to be the main effector of their supportive, angiogenic, and immunomodulatory functions. In this narrative review, we aim to address the impact of obesity on ASCs/MSCs, summarize the current knowledge regarding the potential pathological roles of ASCs/MSCs in the development of breast cancer, discuss related molecular mechanisms, underline the possible clinical significance, and highlight related research perspectives. In particular, we underscore the roles of ASCs/MSCs in breast cancer cell progression, including proliferation and survival, angiogenesis, migration and invasion, the epithelial-mesenchymal transition, cancer stem cell development, immune evasion, therapy resistance, and the potential impact of breast cancer cells on ASCS/MSCs by educating them to become cancer-associated fibroblasts. We conclude that ASCs/MSCs, especially obese ASCs/MSCs, may be key players in the breast cancer microenvironment. Targeting these cells may provide a new path of effective breast cancer treatment.

Adipose stem cells-released extracellular vesicles as a next-generation cargo delivery vehicles: a survey of minimal information implementation, mass production and functional modification

OBJECTIVES

To investigate current situation of minimal information implementation highlighted by minimal information for studies of extracellular vesicles 2018 (MISEV2018) guidelines, and explore technological advances towards mass production and functional modification in aesthetic, plastic and reconstructive surgery.

METHODS

Original articles on extracellular vesicles (EVs) of adipose stem cells (ASCs) were identified. Statistics upon minimal information for EVs research, such as species, cell types, culture conditions, conditioned media harvesting parameters, EVs isolation/storage/identification/quantification, functional uptake and working concentration, were analyzed.

RESULTS

The items of cell culture conditions such as passage number, seeding density, conditioned media harvesting time, functional uptake and working concentration were poorly documented, with a reporting percentage of 47.13%, 54.02%, 29.89%, 62.07% and 36.21%, respectively. However, there were some studies not reporting information of ASCs origin, culture medium, serum, EVs isolation methods, quantification and identification of EVs, accounting for 3.45%, 10.34%, 6.90%, 3.45%, 18.39% and 4.02%, respectively. Serum deprivation and trophic factors stimuli were attempted for EVs mass production. Several technological advances towards functional modification included hypoxia pre-condition, engineering EVs and controlled release. Presently, ASCs EVs have been applied in multiple fields, including diabetic/non-diabetic wound healing, angiogenesis, inflammation modulation, fat grafting, hair regeneration, antiaging, and healing and regeneration of cartilage/bone/peripheral nerve/tendon.

CONCLUSION

Our results highlight normative reporting of ASCs EVs in functional studies to increase reliability and reproducibility of scientific publications. The advances towards mass production and functional modification of ASCs EVs are also recommended to enhance therapeutic effects.

Adipose Stromal/Stem Cell-Derived Extracellular Vesicles: Potential Next-Generation Anti-Obesity Agents

Over the last decade, several compounds have been identified for the treatment of obesity. However, due to the complexity of the disease, many pharmacological interventions have raised concerns about their efficacy and safety. Therefore, it is important to discover new factors involved in the induction/progression of obesity. Adipose stromal/stem cells (ASCs), which are mostly isolated from subcutaneous adipose tissue, are the primary cells contributing to the expansion of fat mass. Like other cells, ASCs release nanoparticles known as extracellular vesicles (EVs), which are being actively studied for their potential applications in a variety of diseases. Here, we focused on the importance of the contribution of ASC-derived EVs in the regulation of metabolic processes. In addition, we outlined the advantages/disadvantages of the use of EVs as potential next-generation anti-obesity agents.

Potential Applications and Functional Roles of Exosomes in Cardiometabolic Disease

Despite diagnostic and therapeutic advances, cardiometabolic disease remains the leading cause of death worldwide. Extracellular vesicles (EVs), which include exosomes and microvesicles, have gained particular interest because of their role in metabolic homeostasis and cardiovascular physiology. Indeed, EVs are recognized as critical mediators of intercellular communication in the cardiovascular system. Exosomes are naturally occurring nanocarriers that transfer biological information in the setting of metabolic abnormalities and cardiac dysfunction. The study of these EVs can increase our knowledge on the pathophysiological mechanisms of metabolic disorders and their cardiovascular complications. Because of their inherent properties and composition, exosomes have been proposed as diagnostic and prognostic biomarkers and therapeutics for specific targeting and drug delivery. Emerging fields of study explore the use exosomes as tools for gene therapy and as a cell-free alternative for regenerative medicine. Furthermore, innovative biomaterials can incorporate exosomes to enhance tissue regeneration and engineering. In this work, we summarize the most recent knowledge on the role of exosomes in cardiometabolic pathophysiology while highlighting their potential therapeutic applications.