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1.
J Zhejiang Univ Sci B ; 25(7): 594-604, 2024 May 17.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-39011679

RESUMEN

Liver fibrosis is a significant health burden, marked by the consistent deposition of collagen. Unfortunately, the currently available treatment approaches for this condition are far from optimal. Lysyl oxidase-like protein 2 (LOXL2) secreted by hepatic stellate cells (HSCs) is a crucial player in the cross-linking of matrix collagen and is a significant target for treating liver fibrosis. Mesenchymal stem cell-derived small extracellular vesicles (MSC-sEVs) have been proposed as a potential treatment option for chronic liver disorders. Previous studies have found that MSC-sEV can be used for microRNA delivery into target cells or tissues. It is currently unclear whether microRNA-4465 (miR-4465) can target LOXL2 and inhibit HSC activation. Additionally, it is uncertain whether MSC-sEV can be utilized as a gene therapy vector to carry miR-4465 and effectively inhibit the progression of liver fibrosis. This study explored the effect of miR-4465-modified MSC-sEV (MSC-sEVmiR-4465) on LOXL2 expression and liver fibrosis development. The results showed that miR-4465 can bind specifically to the promoter of the LOXL2 gene in HSC. Moreover, MSC-sEVmiR-4465 inhibited HSC activation and collagen expression by downregulating LOXL2 expression in vitro. MSC-sEVmiR-4465 injection could reduce HSC activation and collagen deposition in the CCl4-induced mouse model. MSC-sEVmiR-4465 mediating via LOXL2 also hindered the migration and invasion of HepG2 cells. In conclusion, we found that MSC-sEV can deliver miR-4465 into HSC to alleviate liver fibrosis via altering LOXL2, which might provide a promising therapeutic strategy for liver diseases.


Asunto(s)
Aminoácido Oxidorreductasas , Vesículas Extracelulares , Células Estrelladas Hepáticas , Cirrosis Hepática , Células Madre Mesenquimatosas , MicroARNs , Aminoácido Oxidorreductasas/genética , Aminoácido Oxidorreductasas/metabolismo , Animales , Células Madre Mesenquimatosas/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Ratones , Cirrosis Hepática/terapia , Cirrosis Hepática/metabolismo , Cirrosis Hepática/genética , Vesículas Extracelulares/metabolismo , Células Estrelladas Hepáticas/metabolismo , Masculino , Humanos , Ratones Endogámicos C57BL
2.
J Bone Oncol ; 47: 100610, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38984147

RESUMEN

The skeleton is a common site of cancer metastasis and malignancy with the resultant lesions often being incurable. Interactions between metastatic cancer cells and the bone microenvironment are critical for cancer cell survival, outgrowth, and progression. Mesenchymal Stem Cells (MSCs) are an essential stromal cell type in bone that are appreciated for their impacts on cancer-induced bone disease, however, newer evidence suggests that MSCs possess extensive roles in cancer-bone crosstalk, including cancer cell dormancy, metabolic demands, and immune-oncology. Emerging evidence has also identified the importance of MSC tissue source and the influence of ageing when studying MSC biology. Combining these considerations together with developing technologies such as spatial transcriptomics will contribute to defining the molecular mechanisms underlying complex stroma-cancer interactions in bone and assist with identification of therapeutically tractable targets.

3.
Ultrastruct Pathol ; 48(4): 274-296, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38946300

RESUMEN

Sepsis denotes a serious high mortality concern. The study was designed to evaluate the effect of mesenchymal stem cell exosomes (MSC-exosomes) on the evolution of the animal model of sepsis. In this study, 36 rats were distributed into three groups, (I) controls, (II) LPS-treated, and (III) LPS+MSC-EVs. Sepsis was simulated by administering E. coli-LPS to the laboratory animals. Group III was given MSC-exosomes four hours after the LPS injection. Forty-eight hours later rats were sacrificed. Ileum samples were excised, and processed for the histological assessment, immunohistochemical identification of CD44, and inducible nitric oxide synthase (iNOS). Ileum homogenate was used to estimate tumor necrosis factor α (TNF α) besides Cyclooxygenase-2 (COX 2). PCR was used for the detection of interleukin 1α (IL­1α), and interleukin 17 (IL­17). Statistical and morphometrical analysis was done. The LPS-treated group showed increased TNF-α, IL­1α, IL­17, and decreased COX 2. LPS administration led to cytoplasmic vacuolization of enterocytes, an increase in the vasculature, and cellular infiltrations invaded the lamina propria. There was a significant rise in goblet cells and the proportion of collagen fibers. Ultrastructurally, the enterocytes displayed nuclear irregularity, rough endoplasmic reticulum (rER) dilatation, and increased mitochondria number. Sepsis induces a significant increase in iNOS and a decrease in CD44 immune expressions. LPS+MSC-EVs group restored normal ileum structure and revealed a significant elevation in CD44 and a reduction in iNOS immunoreactions. LPS-sepsis induced an obvious ileum inflammatory deterioration ameliorated by MSC-exosomes, mostly through their antioxidant, anti-inflammatory, and anti-apoptotic properties.


Asunto(s)
Modelos Animales de Enfermedad , Exosomas , Íleon , Células Madre Mesenquimatosas , Sepsis , Animales , Sepsis/complicaciones , Ratas , Íleon/patología , Exosomas/metabolismo , Masculino , Inmunohistoquímica , Ratas Wistar , Óxido Nítrico Sintasa de Tipo II/metabolismo
4.
Life Sci ; 353: 122915, 2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39013528

RESUMEN

AIM: This study evaluates the safety and efficacy of autologous adipose-derived mesenchymal stem cell-derived exosomes as a treatment for Psoriasis, a chronic immune-related skin and joint disorder, compared to current treatments like topicals, phototherapy, and systemic. MATERIALS AND METHODS: The study isolated exosomes from Mesenchymal Stem Cells(MSCs) of healthy adipose tissue using ultracentrifugation. 12 patients with plaque psoriasis were divided into three groups and given single doses of exosomes. Tissue samples were collected pre- and post-treatment and examined for inflammatory(TNFα, IL23, IL17, IFNγ, CD3) and anti-inflammatory (FOXP3, IL10) markers. The severity of the lesion was also evaluated. KEY FINDINGS: In this study, it was found that erythema and induration (P < 0.05) decreased significantly in patients receiving 200 µg. Still, this reduction in scaling was not significant, the thickness was significantly reduced in patients receiving 100 and 200 µg doses (P < 0.05). H&E evaluation showed that the decreasing trend in these patients was not significant (P > 0.05). IHC evaluation in patients receiving doses of 100 and 200 µg showed a decrease in the presence of IL17 (P < 0.05, <0.001) & CD3(P < 0.001, <0.05) and a considerable increase in FOXP3(P ≤ 0.001), in the tissue samples of the patients. Examining the expression of inflammatory factors also shows that dose 200 µg decreased the expression of IL17(P > 0.05), IFNγ(P > 0.05), IL23(P < 0.05), & TNFα(P ≤ 0.05) and increased the expression of the anti-inflammatory factor IL10(P < 0.05). SIGNIFICANCE: The study indicates that a 200 µg dose is optimal for patients, but a larger patient population is needed for more reliable results. Additionally, higher doses or multiple injections with specific intervals can increase confidence.

5.
Stem Cell Res Ther ; 15(1): 195, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956738

RESUMEN

BACKGROUND: Nowadays, companion and working dogs hold significant social and economic importance. Dry eye, also known as dry keratoconjunctivitis (KCS), a common disease in ophthalmology, can readily impact a dog's working capacity and lead to economic losses. Although there are several medications available for this disease, all of them only improve the symptoms on the surface of the eye, and they are irritating and not easy to use for long periods of time. Adipose-derived mesenchymal stem cells (ADMSC) are promising candidates for tissue regeneration and disease treatment. However, long-term in vitro passaging leads to stemness loss of ADMSC. Here, we aimed to use ADMSC overexpressing Secreted Protein Acidic and Rich in Cysteine (SPARC) to treat 0.25% benzalkonium chloride-treated dogs with dry eye to verify its efficacy. For in vitro validation, we induced corneal epithelial cell (HCECs) damage using 1 µg/mL benzalkonium chloride. METHODS: Fifteen male crossbred dogs were randomly divided into five groups: normal, dry eye self-healing control, cyclosporine-treated, ADMSC-CMV-treated and ADMSC-OESPARC-treated. HCECs were divided into four groups: normal control group, untreated model group, ADMSC-CMV supernatant culture group and ADMSC-OESRARC supernatant culture group. RESULTS: SPARC-modified ADMSC had the most significant effect on canine ocular surface inflammation, corneal injury, and tear recovery, and the addition of ADMSC-OESPARC cell supernatant also had a salvage effect on HCECs cellular damage, such as cell viability and cell proliferation ability. Moreover, analysis of the co-transcriptome sequencing data showed that SPARC could promote corneal epithelial cell repair by enhancing the in vitro viability, migration and proliferation and immunosuppression of ADMSC. CONCLUSION: The in vitro cell test and in vivo model totally suggest that the combination of SPARC and ADMSC has a promising future in novel dry eye therapy.


Asunto(s)
Compuestos de Benzalconio , Modelos Animales de Enfermedad , Síndromes de Ojo Seco , Células Madre Mesenquimatosas , Osteonectina , Animales , Perros , Compuestos de Benzalconio/farmacología , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/citología , Síndromes de Ojo Seco/terapia , Síndromes de Ojo Seco/tratamiento farmacológico , Síndromes de Ojo Seco/metabolismo , Síndromes de Ojo Seco/patología , Osteonectina/metabolismo , Osteonectina/genética , Masculino , Tejido Adiposo/citología , Tejido Adiposo/metabolismo , Trasplante de Células Madre Mesenquimatosas/métodos
6.
MedComm (2020) ; 5(8): e654, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39040848

RESUMEN

Liver fibrosis can cause hepatitis B virus (HBV)-associated hepatocellular carcinoma. Menstrual blood-derived mesenchymal stem cells (MenSCs) can ameliorate liver fibrosis through paracrine. Single-cell RNA sequencing (scRNA-seq) may be used to explore the roadmap of activated hepatic stellate cell (aHSC) inactivation to target liver fibrosis. This study established HBV transgenic (HBV-Tg) mouse model of carbon tetrachloride (CCl4)-induced liver fibrosis and demonstrated that MenSCs migrated to the injured liver to improve serological indices and reduce fibrotic accumulation. RNA-bulk analysis revealed that MenSCs mediated extracellular matrix accumulation and cell adhesion. Liver parenchymal cells and nonparenchymal cells were identified by scRNA-seq in the control, CCl4, and MenSC groups, revealing the heterogeneity of fibroblasts/HSCs. A CellChat analysis revealed that diminished intercellular adhesion molecule (ICAM) signaling is vital for MenSC therapy. Specifically, Icam1 in aHSCs acted on Itgal/Itgb2 and Itgam/Itgb2 in neutrophils, causing decreased adhesion. The expression of Itgal, Itgam, and Itgb2 was higher in CCl4 group than in the control group and decreased after MenSC therapy in neutrophil clusters. The Lcn2, Pglyrp1, Wfdc21, and Mmp8 had high expression and may be potential targets in neutrophils. This study highlights interacting cells, corresponding molecules, and underlying targets for MenSCs in treating HBV-associated liver fibrosis.

7.
FASEB J ; 38(14): e23798, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-38989582

RESUMEN

The role of mesenchymal-stem-cell-derived exosomes (MSCs-Exo) in the regulation of macrophage polarization has been recognized in several diseases. There is emerging evidence that MSCs-Exo partially prevent the progression of diabetic nephropathy (DN). This study aimed to investigate whether exosomes secreted by MSCs pre-treated with a diabetic environment (Exo-pre) have a more pronounced protective effect against DN by regulating the balance of macrophages. Exo-pre and Exo-Con were isolated from the culture medium of UC-MSCs pre-treated with a diabetic mimic environment and natural UC-MSCs, respectively. Exo-pre and Exo-Con were injected into the tail veins of db/db mice three times a week for 6 weeks. Serum creatinine and serum urea nitrogen levels, the urinary protein/creatinine ratio, and histological staining were used to determine renal function and morphology. Macrophage phenotypes were analyzed by immunofluorescence, western blotting, and quantitative reverse transcription polymerase chain reaction. In vitro, lipopolysaccharide-induced M1 macrophages were incubated separately with Exo-Con and Exo-pre. We performed microRNA (miRNA) sequencing to identify candidate miRNAs and predict their target genes. An miRNA inhibitor was used to confirm the role of miRNAs in macrophage modulation. Exo-pre were more potent than Exo-Con at alleviating DN. Exo-pre administration significantly reduced the number of M1 macrophages and increased the number of M2 macrophages in the kidney compared to Exo-Con administration. Parallel outcomes were observed in the co-culture experiments. Moreover, miR-486-5p was distinctly expressed in Exo-Con and Exo-pre groups, and it played an important role in macrophage polarization by targeting PIK3R1 through the PI3K/Akt pathway. Reducing miR-486-5p levels in Exo-pre abolished macrophage polarization modulation. Exo-pre administration exhibited a superior effect on DN by remodeling the macrophage balance by shuttling miR-486-5p, which targets PIK3R1.


Asunto(s)
Nefropatías Diabéticas , Exosomas , Macrófagos , Células Madre Mesenquimatosas , MicroARNs , Cordón Umbilical , Exosomas/metabolismo , Animales , Células Madre Mesenquimatosas/metabolismo , Nefropatías Diabéticas/metabolismo , Ratones , Macrófagos/metabolismo , MicroARNs/metabolismo , MicroARNs/genética , Cordón Umbilical/citología , Cordón Umbilical/metabolismo , Masculino , Ratones Endogámicos C57BL , Activación de Macrófagos
8.
Hum Pathol ; 150: 58-66, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38971328

RESUMEN

DUSP22 rearrangements are genetic alterations observed in a subset of systemic anaplastic large cell lymphoma (S-ALCL), primary cutaneous anaplastic large cell lymphoma (C-ALCL), and lymphomatoid papulosis (LyP). Previous investigations have shown that the LEF1+/TIA1- immunoprofile and MSC E116K mutations are highly associated with DUSP22 rearrangement in ALCL. However, the existing literature primarily focuses on S-ALCL. Our understanding of the LEF1/TIA1 immunoprofile and MSC mutation status in C-ALCL/LyP is still limited. In this study, we aimed to assess LEF1/TIA1 expression and MSC mutations in a cohort of 23 C-ALCL/LyP cases, along with a control group of histological mimickers. DUSP22 rearrangements were detected by fluorescence in situ hybridization in eight cases (6/10 C-ALCL, 2/13 LyP). We found LEF1 expression in five out of eight (63%) DUSP22-rearranged cases (3/6 C-ALCL, 2/2 LyP), and none of the 15 cases lacking DUSP22 rearrangements. Furthermore, we also found frequent LEF1 expression in adult T-cell leukemia/lymphoma (ATLL; 10 of 11, 91%) within the control group. TIA1 expression was consistently negative in all DUSP22-rearranged C-ALCL/LyP and ATLL cases tested. MCS E116K mutation was identified in one of five DUSP22-rearranged C-ALCL cases. RNA sequencing of a DUSP22-rearranged C-ALCL revealed a novel DUSP22::SNHG fusion coexisting with a CD58::WNT2B fusion. In conclusion, our findings demonstrated a lower rate of LEF1 expression in DUSP22-rearranged C-ALCL/LyP compared to previous reports that predominantly focused on S-ALCL. Moreover, we observed that the majority of ATLL cases also expressed LEF1, suggesting that the LEF1+/TIA1- immunoprofile does not differentiate DUSP22-rearranged C-ALCL/LyP from ATLL.

9.
Sci Rep ; 14(1): 16289, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39009606

RESUMEN

Pioneering flexible micro-supercapacitors, designed for exceptional energy and power density, transcend conventional storage limitations. Interdigitated electrodes (IDEs) based on laser-induced graphene (LIG), augmented with metal-oxide modifiers, harness synergies with layered graphene to achieve superior capacitance. This study presents a novel one-step process for sputtered plasma deposition of HfO2, resulting in enhanced supercapacitance performance. Introducing LIG-HfO2 micro-supercapacitor (MSC) devices with varied oxygen flow rates further boosts supercapacitance performance by introducing oxygen functional groups. FESEM investigations demonstrate uniform coating of HfO2 on LIG fibers through sputtering. Specific capacitance measurements reveal 6.4 mF/cm2 at 5 mV/s and 4.5 mF/cm2 at a current density of 0.04 mA/cm2. The LIG-HfO2 devices exhibit outstanding supercapacitor performance, boasting at least a fourfold increase over pristine LIG. Moreover, stability testing indicates a high retention rate of 97% over 5000 cycles, ensuring practical real-time applications.

10.
bioRxiv ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-39005342

RESUMEN

Background: Mesenchymal stromal cell derived extracellular vesicles (MSC-EVs) are a promising therapeutic for neuroinflammation. MSC-EVs can interact with microglia, the resident immune cells of the brain, to exert their immunomodulatory effects. In response to inflammatory cues, such as cytokines, microglia undergo phenotypic changes indicative of their function e.g. morphology and secretion. However, these changes in response to MSC-EVs are not well understood. Additionally, no disease-relevant screening tools to assess MSC-EV bioactivity exist, which has further impeded clinical translation. Here, we developed a quantitative, high throughput morphological profiling approach to assess the response of microglia to neuroinflammation-relevant signals and whether this morphological response can be used to indicate the bioactivity of MSC-EVs. Results: Using an immortalized human microglia cell-line, we observed increased size (perimeter, major axis length) and complexity (form factor) upon stimulation with interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α). Upon treatment with MSC-EVs, the overall morphological score (determined using principal component analysis) shifted towards the unstimulated morphology, indicating that MSC-EVs are bioactive and modulate microglia. The morphological effects of MSC-EVs in TNF-γ/IFN-α stimulated cells were concomitant with reduced secretion of 14 chemokines/cytokines (e.g. CXCL6, CXCL9) and increased secretion of 12 chemokines/cytokines (e.g. CXCL8, CXCL10). Proteomic analysis of cell lysates revealed significant increases in 192 proteins (e.g. HIBADH, MEAK7, LAMC1) and decreases in 257 proteins (e.g. PTEN, TOM1, MFF) with MSC-EV treatment. Of note, many of these proteins are involved in regulation of cell morphology and migration. Gene Set Variation Analysis revealed upregulation of pathways associated with immune response, such as regulation of cytokine production, immune cell infiltration (e.g. T cells, NK cells) and morphological changes (e.g. Semaphorin, RHO/Rac signaling). Additionally, changes in microglia mitochondrial morphology were measured suggesting that MSC-EV modulate mitochondrial metabolism. Conclusion: This study comprehensively demonstrates the effects of MSC-EVs on human microglial morphology, cytokine secretion, cellular proteome, and mitochondrial content. Our high-throughput, rapid, low-cost morphological approach enables screening of MSC-EV batches and manufacturing conditions to enhance EV function and mitigate EV functional heterogeneity in a disease relevant manner. This approach is highly generalizable and can be further adapted and refined based on selection of the disease-relevant signal, target cell, and therapeutic product.

11.
Curr Pharm Des ; 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39051578

RESUMEN

Skin cancer is a prevalent and sometimes lethal cancer that affects a wide range of people. UV radiation exposure is the main cause of skin cancer. Immunosuppression, environmental factors, and genetic predisposition are other contributing variables. Fair-skinned people and those with a history of sunburns or severe sun exposure are more likely to experience this condition. Melanoma, squamous cell carcinoma (SCC), and basal cell carcinoma (BCC) are the three main forms. Melanoma poses a bigger hazard because of its tendency for metastasis, while SCC and BCC have limited metastatic potential. Genetic mutations and changes to signalling pathways such as p53 and MAPK are involved in pathogenesis. Early diagnosis is essential, and molecular testing, biopsy, dermoscopy, and visual inspection can all help. In addition to natural medicines like curcumin and green tea polyphenols, treatment options include immunotherapy, targeted therapy, radiation, surgery, and chemotherapy. Reducing the incidence of skin cancer requires preventive actions, including sun protection and early detection programs. An overview of skin cancers, including their forms, pathophysiology, diagnosis, and treatment, highlighting herbal therapy, is given in this review.

13.
Clin Invest Med ; 47(2): 12-22, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38958475

RESUMEN

PURPOSE: Despite the impact of physician-scientists on scientific discovery and translational medicine, several reports have signalled their declining workforce, reduced funding, and insufficient protected research time. Given the paucity of outcome data on Canadian MD/PhD programs, this study presents a national portrait of the sociodemographic characteristics, training trajectories, productivity, and satisfaction in trainees and alumni from Canadian MD/PhD and MD/MSc programs. METHODS: Quantitative data were collected in a national survey launched in 2021. Respondents included 74 MD/PhD alumni and 121 trainees across 12 Canadian MD/PhD and MD/MSc programs. RESULTS: Among MD/PhD alumni, 51% were independent practitioners/researchers while others underwent residency training. Most trainees (88%) were in MD/PhD programs. Significantly more alumni identified as men than did trainees. Significantly more alumni conducted clinical and health services research, while more trainees conducted basic science research. Average time to MD/PhD completion was 8 years, with no correlation to subsequent research outcomes. Self-reported research productivity was highest during MD/PhD training. Concerning training trajectories, most alumni completed residency, pursued additional training, and practised in Canada. Finally, regression models showed that trainees and alumni were satisfied with programs, with significant moderators in trainee models. CONCLUSION: Survey findings showed Canadian MD/PhD and MD/MSc programs recruit more diverse cohorts of trainees than before, provide productive research years, and graduate alumni who pursue training and academic employment in Canada. Both alumni and trainees are largely satisfied with these training programs. The need to collect in-depth longitudinal data on Canadian MD/PhD graduates to monitor diversity and success metrics is discussed.


Asunto(s)
Satisfacción Personal , Canadá , Humanos , Masculino , Encuestas y Cuestionarios , Femenino , Adulto , Investigación Biomédica/estadística & datos numéricos
14.
Public Health ; 233: 164-169, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38897068

RESUMEN

OBJECTIVES: The purpose of this work is to characterize scenarios under which it may be in a donor country's own public health interests to donate vaccine doses to another country before its own population has been fully vaccinated. In these scenarios, vaccinating other countries can delay the evolution of new variants of the virus, decrease total deaths, and, in some cases, decrease deaths in the donor countries. STUDY DESIGN: We simulate the effects of different vaccine donation policies using an epidemiological model employing COVID-19 transmission parameters. METHODS: We use the epidemiological model of Holleran et al. that incorporates virus mutation to simulate epidemic progression and estimate numbers of deaths arising from several vaccine allocation policies (donor-first, non-donor-first, and vaccine sharing) across a number of scenarios. We analyze the results in light of herd immunity limits derived in Holleran et al. RESULTS: We identify realistic scenarios under which a donor country prefers to donate vaccines before distributing them locally in order to minimize local deaths during a pandemic. We demonstrate that a non-donor-first vaccination policy can delay, sometimes dramatically, the emergence of more-contagious variants. Even more surprising, donating all vaccines is sometimes better for the donor country than a sharing policy in which half of the vaccines are donated, and half are retained because of the impact donation can have on delaying the emergence of a more contagious virus. Non-donor-first vaccine allocation is optimal in scenarios in which the local health impact of the vaccine is limited or when delaying the emergence of a variant is especially valuable. CONCLUSION: In all cases, we find that vaccine distribution is not a zero-sum game between donor and non-donor countries, illustrating the general moral reasons to donate vaccines. In some cases, donor nations can also realize local health benefits from donating vaccines. The insights yielded by this framework can be used to guide equitable vaccine distribution in future pandemics.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Política de Salud , Humanos , COVID-19/prevención & control , COVID-19/epidemiología , Vacunas contra la COVID-19/administración & dosificación , SARS-CoV-2 , Pandemias/prevención & control , Modelos Epidemiológicos , Inmunidad Colectiva , Vacunación/estadística & datos numéricos
15.
Biomed Pharmacother ; 176: 116836, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38850660

RESUMEN

Alzheimer's disease (AD) is a devastating neurological condition characterized by cognitive decline, motor coordination impairment, and amyloid plaque accumulation. The underlying molecular mechanisms involve oxidative stress, inflammation, and neuronal degeneration. This study aimed to investigate the therapeutic effects of mesenchymal stem cell-derived exosomes (MSC-exos) on AD and explore the molecular pathways involved, including the PI3K/Akt/mTOR axis, autophagy, and neuroinflammation. To assess the potential of MSC-exos for the treatment of AD, rats were treated with AlCl3 (17 mg/kg/once/day) for 8 weeks, followed by the administration of an autophagy activator (rapamycin), or MSC-exos with or without an autophagy inhibitor (3-methyladenin; 3-MA+ chloroquine) for 4 weeks. Memory impairment was tested, and brain tissues were collected for gene expression analyses, western blotting, histological studies, immunohistochemistry, and transmission electron microscopy. Remarkably, the administration of MSC-exos improved memory performance in AD rats and reduced the accumulation of amyloid-beta (Aß) plaques and tau phosphorylation. Furthermore, MSC-exos promoted neurogenesis, enhanced synaptic function, and mitigated astrogliosis in AD brain tissues. These beneficial effects were associated with the modulation of autophagy and the PI3K/Akt/mTOR signalling pathway, as well as the inhibition of neuroinflammation. Additionally, MSC-exos were found to regulate specific microRNAs, including miRNA-21, miRNA-155, miRNA-17-5p, and miRNA-126-3p, further supporting their therapeutic potential. Histopathological and bioinformatic analyses confirmed these findings. This study provides compelling evidence that MSC-exos hold promise as a potential therapeutic approach for AD. By modulating the PI3K/Akt/mTOR axis, autophagy, and neuroinflammation, MSC-exos have the potential to improve memory, reduce Aß accumulation, enhance neurogenesis, and mitigate astrogliosis. These findings shed light on the therapeutic potential of MSC-exos and highlight their role in combating AD.


Asunto(s)
Enfermedad de Alzheimer , Autofagia , Exosomas , Células Madre Mesenquimatosas , Transducción de Señal , Animales , Masculino , Ratas , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/terapia , Autofagia/efectos de los fármacos , Autofagia/fisiología , Modelos Animales de Enfermedad , Exosomas/metabolismo , Insulina/metabolismo , Células Madre Mesenquimatosas/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas Sprague-Dawley , Serina-Treonina Quinasas TOR/metabolismo
16.
Ageing Res Rev ; 99: 102391, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38914266

RESUMEN

Cellular senescence (CS) is recognized as one of the hallmarks of aging, and an important player in a variety of age-related pathologies. Accumulation of senescent cells can promote a pro-inflammatory and pro-cancerogenic microenvironment. Among potential senotherapeutics are extracellular vesicles (EVs) (40-1000 nm), including exosomes (40-150 nm), that play an important role in cell-cell communications. Here, we review the most recent studies on the impact of EVs derived from stem cells (MSCs, ESCs, iPSCs) as well as non-stem cells of various types on CS and discuss potential mechanisms responsible for the senotherapeutic effects of EVs. The analysis revealed that (i) EVs derived from stem cells, pluripotent (ESCs, iPSCs) or multipotent (MSCs of various origin), can mitigate the cellular senescence phenotype both in vitro and in vivo; (ii) this effect is presumably senomorphic; (iii) EVs display cross-species activity, without apparent immunogenic responses. In summary, stem cell-derived EVs appear to be promising senotherapeutics, with a feasible application in humans.


Asunto(s)
Senescencia Celular , Vesículas Extracelulares , Senoterapéuticos , Humanos , Vesículas Extracelulares/fisiología , Senescencia Celular/fisiología , Animales , Senoterapéuticos/farmacología , Células Madre/fisiología , Envejecimiento/fisiología
17.
bioRxiv ; 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38826475

RESUMEN

Genome-wide association studies (GWASs) have identified many sources of genetic variation associated with bone mineral density (BMD), a clinical predictor of fracture risk and osteoporosis. Aside from the identification of causal genes, other difficult challenges to informing GWAS include characterizing the roles of predicted causal genes in disease and providing additional functional context, such as the cell type predictions or biological pathways in which causal genes operate. Leveraging single-cell transcriptomics (scRNA-seq) can assist in informing BMD GWAS by linking disease-associated variants to genes and providing a cell type context for which these causal genes drive disease. Here, we use large-scale scRNA-seq data from bone marrow-derived stromal cells cultured under osteogenic conditions (BMSC-OBs) from Diversity Outbred (DO) mice to generate cell type-specific networks and contextualize BMD GWAS-implicated genes. Using trajectories inferred from the scRNA-seq data, we identify networks enriched with genes that exhibit the most dynamic changes in expression across trajectories. We discover 21 network driver genes, which are likely to be causal for human BMD GWAS associations that colocalize with expression/splicing quantitative trait loci (eQTL/sQTL). These driver genes, including Fgfrl1 and Tpx2, along with their associated networks, are predicted to be novel regulators of BMD via their roles in the differentiation of mesenchymal lineage cells. In this work, we showcase the use of single-cell transcriptomics from mouse bone-relevant cells to inform human BMD GWAS and prioritize genetic targets with potential causal roles in the development of osteoporosis.

18.
Sci Rep ; 14(1): 13406, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38862672

RESUMEN

This article investigates an inventive methodology for precisely and efficiently controlling photovoltaic emulating (PVE) prototypes, which are employed in the assessment of solar systems. A modification to the Shift controller (SC), which is regarded as a leading PVE controller, is proposed. In addition to efficiency and accuracy, the novel controller places a high emphasis on improving transient performance. The novel piecewise linear-logarithmic adaptation utilized by the Modified-Shift controller (M-SC) enables the controller to linearly adapt to the load burden within a specified operating range. At reduced load resistances, the transient sped of the PVE can be increased through the implementation of this scheme. An exceedingly short settling time of the PVE is ensured by a logarithmic modification of the control action beyond the critical point. In order to analyze the M-SC in the context of PVE control, numerical investigations implemented in MATLAB/Simulink (Version: Simulink 10.4, URL: https://in.mathworks.com/products/simulink.html ) were utilized. To assess the effectiveness of the suggested PVE, three benchmarking profiles are presented: eight scenarios involving irradiance/PVE load, continuously varying irradiance/temperature, and rapidly changing loads. These profiles include metrics such as settling time, efficiency, Integral of Absolute Error (IAE), and percentage error (epve). As suggested, the M-SC attains an approximate twofold increase in speed over the conventional SC, according to the findings. This is substantiated by an efficiency increase of 2.2%, an expeditiousness enhancement of 5.65%, and an IAE rise of 5.65%. Based on the results of this research, the new M-SC enables the PVE to experience perpetual dynamic operation enhancement, making it highly suitable for evaluating solar systems in ever-changing environments.

19.
J Extracell Vesicles ; 13(6): e12463, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38868945

RESUMEN

Mesenchymal stromal cells (MSCs) are promising regenerative therapeutics that primarily exert their effects through secreted extracellular vesicles (EVs). These EVs - being small and non-living - are easier to handle and possess advantages over cellular products. Consequently, the therapeutic potential of MSC-EVs is increasingly investigated. However, due to variations in MSC-EV manufacturing strategies, MSC-EV products should be considered as highly diverse. Moreover, the diverse array of EV characterisation technologies used for MSC-EV characterisation further complicates reliable interlaboratory comparisons of published data. Consequently, this study aimed to establish a common method that can easily be used by various MSC-EV researchers to characterise MSC-EV preparations to facilitate interlaboratory comparisons. To this end, we conducted a comprehensive inter-laboratory assessment using a novel multiplex bead-based EV flow cytometry assay panel. This assessment involved 11 different MSC-EV products from five laboratories with varying MSC sources, culture conditions, and EV preparation methods. Through this assay panel covering a range of mostly MSC-related markers, we identified a set of cell surface markers consistently positive (CD44, CD73 and CD105) or negative (CD11b, CD45 and CD197) on EVs of all explored MSC-EV preparations. Hierarchical clustering analysis revealed distinct surface marker profiles associated with specific preparation processes and laboratory conditions. We propose CD73, CD105 and CD44 as robust positive markers for minimally identifying MSC-derived EVs and CD11b, CD14, CD19, CD45 and CD79 as reliable negative markers. Additionally, we highlight the influence of culture medium components, particularly human platelet lysate, on EV surface marker profiles, underscoring the influence of culture conditions on resulting EV products. This standardisable approach for MSC-EV surface marker profiling offers a tool for routine characterisation of manufactured EV products in pre-clinical and clinical research, enhances the quality control of MSC-EV preparations, and hopefully paves the way for higher consistency and reproducibility in the emerging therapeutic MSC-EV field.


Asunto(s)
Biomarcadores , Vesículas Extracelulares , Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/citología , Humanos , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/química , Biomarcadores/metabolismo , Citometría de Flujo/métodos , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/análisis , Células Cultivadas , Antígenos CD/metabolismo
20.
Tissue Cell ; 88: 102427, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38833940

RESUMEN

Exosomes which are tiny extracellular vesicles (30-150 nm), transport vital proteins and gene materials such as miRNA, mRNA, or DNA, whose role in cell communication and epithelia regulation is critical. Many techniques have been developed as a result of studying exosomes' biochemical and physicochemical properties, although there is still no standard method to isolate exosomes simply with high yield. Commercial kits have gained popularity for exosome extraction despite concerns about their effectiveness in scientific research. On the other hand, ultracentrifugation remains the gold standard isolation method. This study compares these two common exosome isolation methods to determine their impact on the quality and quantity of exosomes isolated from bone marrow (BM) and Wharton's jelly (WJ)-derived mesenchymal stem cells. Isolated exosomes from the two sources of the cell's conditioned medium by two methods (polymer kit and ultracentrifuge) were characterized using western blotting, scanning electron microscopy (SEM), dynamic light scattering (DLS), and the Bradford assay. Western blot analysis confirmed separation efficiency based on CD81 and CD63 markers, with the absence of calnexin serving as a negative control. The Morphology of exosomes studied by SEM image analysis revealed a similar round shape appearance and their sizes (30-150 nm) were the same in both isolation techniques. The DLS analysis of the sample results was consistent with the SEM ones, showing a similar size range and very low disparity. The exosome protein content concentration analysis revealed that exosomes isolated by the polymer-based kits contained higher protein concentration density and purity (p <0.001). In general, though the protein yield was higher when the polymer-based kits were used, there were no significant differences in morphology, or size between WJ-derived and BM-derived exosomes, regardless of the isolation method employed.


Asunto(s)
Células de la Médula Ósea , Exosomas , Células Madre Mesenquimatosas , Ultracentrifugación , Gelatina de Wharton , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/citología , Exosomas/metabolismo , Exosomas/ultraestructura , Exosomas/química , Humanos , Ultracentrifugación/métodos , Gelatina de Wharton/citología , Gelatina de Wharton/metabolismo , Células de la Médula Ósea/metabolismo , Células de la Médula Ósea/citología , Polímeros/química
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