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Background: Several studies have shown that sodium-dependent glucose transporter 2 inhibitors can be used in the treatment of heart failure. This article summarized systematic reviews of sodium-dependent glucose transporter 2 inhibitors in the treatment of heart failure in order to evaluate efficacy and safety. Methods: We systematically searched eight electronic databases from inception to July 2023. We used Assessment of Multiple Systematic Reviews 2 to evaluate the methodological quality, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 to assess report quality, Risk of Bias in Systematic Review to assess the risk of bias, and Grading of Recommendations Assessment, Development, and Evaluation to rate the quality of evidence. Outcome: A total of 36 systematic reviews were included. Our results were classified as clear evidence of benefit: hospitalization for heart failure; possible benefit: cardiovascular death (mortality) and renal outcome composite; clear evidence of no effect or equivalence: atrial arrhythmias, ventricular arrhythmia, atrial fibrillation, and hypotension; possible harm: genital infection; insufficient evidence to draw a conclusion: atrial flutter, major adverse cardiovascular events, urinary tract infection, acute kidney injury, hypoglycemia, and bone fracture. Conclusions: Sodium-dependent glucose transporter 2 inhibitors are beneficial for the treatment of heart failure, especially in terms of heart failure hospitalization.
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BACKGROUND & AIMS: Short-term intensive fasting (STIF), known as beego in Chinese phonetic articulation, has been practiced for more than two thousand years. However, the potential risk of STIF and the body's response to the risk have not been adequately evaluated. This study aims to address this issue, focusing on the STIF-triggered metabolic response of the liver and kidney. METHODS: The STIF procedure in the clinical trial includes a 7-day water-only intensive fasting phase and a 7-day gradual refeeding phase followed by a regular diet. The intensive fasting in humans was assisted with psychological induction. To gain insights not available in the clinical trial, we designed a STIF program for mice that resulted in similar phenotypes seen in humans. Plasma metabolic profiling and examination of gene expression as well as liver and kidney function were performed by omics, molecular, biochemical and flow cytometric analyses. A human cell line model was also used for mechanistic study. RESULTS: Clinically significant metabolites of fat and protein were found to accumulate during the fasting phase, but they were relieved after gradual refeeding. Metabolomics profiling revealed a universal pattern in the consumption of metabolic intermediates, in which pyruvate and succinate are the two key metabolites during STIF. In the STIF mouse model, the accumulation of metabolites was mostly counteracted by the upregulation of catabolic enzymes in the liver, which was validated in a human cell model. Kidney filtration function was partially affected by STIF but could be recovered by refeeding. STIF also reduced oxidative and inflammatory levels in the liver and kidney. Moreover, STIF improved lipid metabolism in mice with fatty liver without causing accumulation of metabolites after STIF. CONCLUSIONS: The accumulation of metabolites induced by STIF can be relieved by spontaneous upregulation of catabolic enzymes, suggesting an adaptive and protective metabolic response to STIF stress in the mammalian body.
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Dieta , Jejum , Camundongos , Humanos , Animais , Fígado/metabolismo , Metabolismo dos Lipídeos , MamíferosRESUMO
Polyelectrolyte complexes (PECs) have emerged as an attractive category of materials for their water processability and some similarities to natural biopolymers. Herein, we employ the intrinsic hydroplasticity of PEC materials to enable the generation of porous structures with the aid of gas foaming. Such foamable materials are fabricated by simply mixing polycation, polyanion, and a UV-initiated chemical foaming agent in an aqueous solution, followed by molding into thin films. The gas foaming of the PEC films can be achieved upon exposure to UV illumination under water, where the films are plasticized and the gaseous products from the photolysis of foaming agents afford the formation, expanding, and merging of numerous bubbles. The porosity and morphology of the resulting porous films can be customized by tuning film composition, foaming conditions, and especially the degree of plasticizing effect, illustrating the high flexibility of this hydroplastic foaming method. Due to the rapid initiation of gas foaming, the present method enables the formation of porous structures via an instant one-step process, much more efficient than those existing strategies for porous PEC materials. More importantly, such a pore-forming mechanism might be extended to other hydroplastic materials (e.g., biopolymers) and help to yield hydroplasticity-based processing strategies.
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The characteristics of biofilms have exacerbated the issue of clinical antibiotic resistance, rendering it a pressing challenge in need of resolution. The combination of biofilm-dispersing agents and antibiotics can eliminate biofilms and promote healing synergistically in infected wounds. In this study, we developed a novel nanocomposite hydrogel (NC gel) comprised of the poly(lactic acid)-hyperbranched polyglycerol (PLA-HPG) based bioadhesive nanoparticles (BNPs) and a hydrophilic carboxymethyl chitosan (CS) network. The NC gel was designed to co-deliver two biofilm-dispersing agents (an NO-donor SNO, and an α-amylase Am) and an antibiotic, cefepime (Cef), utilizing a synergistic anti-biofilm mechanism in which Am loosens the matrix structure and NO promotes the release of biofilm bacteria via quorum sensing, and Cef kills bacteria. The drug-loaded NC gel (SNO/BNP/CS@Am-Cef) demonstrated sustained drug release, minimal cytotoxicity, and increased drug-bacterial interactions at the site of infection. When applied to mice infected with methicillin-resistant Staphylococcus aureus (MRSA) biofilms in vivo, SNO/BNP/CS@Am-Cef enhanced biofilm elimination and promoted wound healing compared to traditional antibiotic treatments. Our work demonstrates the feasibility of the co-delivery of biofilm-dispersing agents and antibiotics using the NC gel and presents a promising approach for the polytherapy of bacterial biofilm-related infections.
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Infecções Bacterianas , Staphylococcus aureus Resistente à Meticilina , Animais , Camundongos , Nanogéis , Antibacterianos/farmacologia , Antibacterianos/química , Biofilmes , Hidrogéis/química , Testes de Sensibilidade MicrobianaRESUMO
Lung cancer is one of the most common cancers in the world, and its treatment strategy is mainly surgery combined with radiotherapy and chemotherapy. However, long-term chemotherapy will result in drug resistance, which is also one of the difficulties in the treatment of lung cancer. Ferroptosis is an iron-dependent and lipid peroxidation-driven non-apoptotic cell death cascade, occurring when there is an imbalance of redox homeostasis in the cell. Nuclear factor erythroid 2-related factor 2 (Nrf2) is key for cellular antioxidant responses. Numerous studies suggest that Nrf2 assumes an extremely important role in regulation of ferroptosis, for its various functions in iron, lipid, and amino acid metabolism, and so on. In this review, a brief overview of the research progress of ferroptosis over the past decade will be presented. In particular, the mechanism of ferroptosis and the regulation of ferroptosis by Nrf2 will be discussed, as well as the role of the Nrf2 pathway and ferroptosis in tumor drug resistance, which will provide new research directions for the treatment of drug-resistant lung cancer patients.â©.
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Ferroptose , Neoplasias Pulmonares , Humanos , Fator 2 Relacionado a NF-E2/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Resistencia a Medicamentos Antineoplásicos , FerroRESUMO
BACKGROUND: Fasting is known to influence the immune functions of leukocytes primarily by regulating their mobilization and redistribution between the bone marrow and the peripheral tissues or circulation, in particular via relocalization of leukocytes back in the bone marrow. However, how the immune system responds to the increased risk of invasion by infectious pathogens with fewer leukocytes in the peripheral blood during fasting intervention remains an open question. RESULTS: We used proteomic, biochemical and flow cytometric tools to evaluate the impact of short-term intensive fasting (STIF), known as beego, on red blood cells by profiling the cells from the STIF subjects before and after 6 days of fasting and 6 days of gradual refeeding. We found that STIF, by triggering the activation of the complement system via the complement receptor on the membrane of red blood cells, boosts fairly sustainable function of red blood cells in immune responses in close relation to various pathogens, including viruses, bacteria and parasites, particularly with the pronounced capacity to defend against SARS-CoV-2, without compromising their oxygen delivery capacity and viability. CONCLUSION: STIF fosters the immune function of red blood cells and therefore, it may be considered as a nonmedical intervention option for the stronger capacity of red blood cells to combat infectious diseases.
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The aquaculture area in China's coastal waters has increased rapidly from 6000 km2 in 1990 to 22,000 km2 in 2020. Despite extensive research regarding the effect of coastal aquaculture on water and sediment pollution, evaluating the quantitative relationship between aquaculture and pollutants remains challenging. Sansha Bay, the world's largest cage aquaculture base for Pseudosciaena crocea, is a typical enclosed bay used for investigating aquaculture pollution. A cage culture database is established from 2000 to 2020 in Sansha Bay. Meanwhile, 236 sediment samples from 3 sediment cores and 67 water samples from 4 transects are obtained from the bay for experiments. The main indicators are five nutrients (NO3-, SiO32-, PO43-, NH4+, and NO2-) in the water samples, the grain size, the heavy metal (Zn, Cu, Pb, Cr, Cd, and As) content, and the 210Pb radioactivity in sediment samples. Based on data obtained and a new calculation method, the annual increment in Zn, Cu, As, Cd, Pb, and Cr contents in the cultured zone is shown to increase by 2137 %, 1881 %, 506 %, 300 %, 202 %, and 118 % in 2000-2018, respectively, as compared with the levels in a noncultured zone. The activities of the cage culture increased NO3- by 9 %, PO43- by 30 %, NH4+ by 115 %, and NO2- by 232 %, compared with natural conservative mixing processes, such as the mixing of SiO32-, in 2020. A novel quantitative approach with broad applicability is proposed to evaluate the magnitude of anthropogenically induced environmental contamination. The effectiveness of the proposed technique is demonstrated through a case study conducted in Sansha Bay, China.
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The bone marrow niche maintains hematopoietic stem cell (HSC) homeostasis and declines in function in the physiologically aging population and in patients with hematological malignancies. A fundamental question is now whether and how HSCs are able to renew or repair their niche. Here, we show that disabling HSCs based on disrupting autophagy accelerated niche aging in mice, whereas transplantation of young, but not aged or impaired, donor HSCs normalized niche cell populations and restored niche factors in host mice carrying an artificially harassed niche and in physiologically aged host mice, as well as in leukemia patients. Mechanistically, HSCs, identified using a donor lineage fluorescence-tracing system, transdifferentiate in an autophagy-dependent manner into functional niche cells in the host that include mesenchymal stromal cells and endothelial cells, previously regarded as "nonhematopoietic" sources. Our findings thus identify young donor HSCs as a primary parental source of the niche, thereby suggesting a clinical solution to revitalizing aged or damaged bone marrow hematopoietic niche.
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Medula Óssea , Células-Tronco Mesenquimais , Camundongos , Animais , Células Endoteliais , Nicho de Células-Tronco/fisiologia , Células-Tronco Hematopoéticas , Células da Medula Óssea , Hematopoese/fisiologiaRESUMO
Because of tumor heterogeneity and the immunosuppressive tumor microenvironment, most cancer vaccines typically do not elicit robust antitumor immunological responses in clinical trials. In this paper, we report findings about a bioadhesive nanoparticle (BNP)-based separable cancer vaccine, FeSHK@B-ovalbumin (OVA), to target multi-epitope antigens and exert effective cancer immunotherapy. After the FeSHK@B-OVA "nanorocket" initiates the "satellite-rocket separation" procedure in the acidic tumor microenvironment, the FeSHK@B "launch vehicle" can amplify intracellular oxidative stress persistently. This procedure allows for bioadhesiveness-mediated prolonged drug retention within the tumor tissue and triggers the immunogenic death of tumor cells that transforms the primary tumors into antigen depots, which acts synergistically with the OVA "satellite" to trigger robust antigen-specific antitumor immunity. The cooperation of these two immunostimulants not only efficiently inhibits the primary tumor growth and provokes durable antigen-specific immune activation in vivo but also activates a long-term and robust immune memory effect to resist tumor rechallenge and metastasis. These results highlight the enormous potential of FeSHK@B-OVA to serve as an excellent therapeutic and prophylactic cancer nanovaccine. By leveraging the antigen depots in situ and the synergistic effect among multi-epitope antigens, such a nanovaccine strategy with stealthy bioadhesion may offer a straightforward and efficient approach to developing various cancer vaccines for different types of tumors.
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BACKGROUND: Lung squamous cell carcinoma (LUSC) currently has limited therapeutic options because of the relatively few validated targets and the lack of clinical drugs for some of these targets. Although NRF2/NFE2L2 pathway activation commonly occurs in LUSC, NRF2 has predominantly been studied in other cancer models. Here, we investigated the function of NRF2 in LUSC, including in organoid models, and we explored the activity of a small molecule NRF2 inhibitor ML385, which has not previously been investigated in LUSC. METHODS: We first explored the role of NRF2 signaling in LUSC cancer cell line and organoid proliferation through NRF2 knockdown or ML385 treatment, both in vivo and in vitro. Next, we performed Western blot and immunofluorescence assays to determine the effect of NRF2 inhibition on PI3K-mTOR signaling. Finally, we used cell viability and clonogenic assays to explore whether ML385 could sensitize LUSC cancer cells to PI3K inhibitors. RESULTS: We find that downregulation of NRF2 signaling inhibited proliferation of LUSC cancer cell lines and organoids, both in vivo and in vitro. We also demonstrate that inhibition of NRF2 reduces PI3K-mTOR signaling, with two potential mechanisms being involved. Although NRF2 promotes AKT phosphorylation, it also acts downstream of AKT to increase RagD protein expression and recruitment of mTOR to lysosomes after amino acid stimulation. We also find that ML385 potentiates LUSC growth inhibition by a pan-PI3K inhibitor, which correlates with stronger inhibition of PI3K-mTOR signaling. CONCLUSIONS: Our data provide additional support for NRF2 promoting LUSC growth through PI3K-mTOR activation and support development of NRF2 inhibitors for the treatment of LUSC.
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Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/patologia , Inibidores de Fosfoinositídeo-3 Quinase/uso terapêutico , Neoplasias Pulmonares/patologia , Pulmão/patologiaRESUMO
Diabetic chronic wound is one of the most serious complications of diabetes, imposing enormous socioeconomic burdens on diabetic patients, their families, and society due to its refractory nature. MicroRNAs (miRNAs) have emerged as important regulators of various physiological and pathological processes. Abnormalities arise in the regulatory functions of miRNAs in chronic diabetic wounds. Therefore, the modification of miRNAs expression in diabetic wounds is an important channel for the improvement of wound healing. The clinical translation of miRNA-based therapy may become a prospective direction of diabetic wound healing. However, miRNA-based therapy is still in its early stage of development, and actual translation into clinical application will take a long time. Herein, we summarized the latest research findings on miRNAs in diabetic chronic wounds healing.
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Diabetes Mellitus , MicroRNAs , Humanos , MicroRNAs/genética , Estudos Prospectivos , Cicatrização/genéticaRESUMO
The morbidity and mortality of lung cancer ranks among the top cancers in the world. Non-small cell lung cancer (NSCLC) is the main pathological type of lung cancer, with limited treatment options and poor prognosis. The nuclear factor E2-related factor 2 (NRF2) signaling pathway is highly mutated and activated in NSCLC, and promotes the malignant progression of lung cancer through various mechanisms. NRF2-targeted therapy will provide new treatment strategies for patients with NSCLC. This article will review the basic structure and response pathways of the NRF2 pathway, the mechanism of NRF2 regulating lung cancer cell proliferation, and the research and development progress of NRF2 inhibitors.â©.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Neoplasias Pulmonares/patologia , Regulação Neoplásica da Expressão Gênica , Transdução de Sinais , Proliferação de CélulasRESUMO
Previous studies have shown that long-term light or moderate fasting such as intermittent fasting can improve health and prolong lifespan. However, in humans short-term intensive fasting, a complete water-only fasting has little been studied. Here, we used multi-omics tools to evaluate the impact of short-term intensive fasting on immune function by comparison of the CD45+ leukocytes from the fasting subjects before and after 72-h fasting. Transcriptomic and proteomic profiling of CD45+ leukocytes revealed extensive expression changes, marked by higher gene upregulation than downregulation after fasting. Functional enrichment of differentially expressed genes and proteins exposed several pathways critical to metabolic and immune cell functions. Specifically, short-term intensive fasting enhanced autophagy levels through upregulation of key members involved in the upstream signals and within the autophagy machinery, whereas apoptosis was reduced by down-turning of apoptotic gene expression, thereby increasing the leukocyte viability. When focusing on specific leukocyte populations, peripheral neutrophils are noticeably increased by short-term intensive fasting. Finally, proteomic analysis of leukocytes showed that short-term intensive fasting not only increased neutrophil degranulation, but also increased cytokine secretion. Our results suggest that short-term intensive fasting boost immune function, in particular innate immune function, at least in part by remodeling leukocytes expression profile.
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Jejum/sangue , Imunidade Inata , Neutrófilos/imunologia , Proteoma/imunologia , Transcriptoma/imunologia , Adolescente , Adulto , Idoso , Apoptose/genética , Apoptose/imunologia , Autofagia/genética , Autofagia/imunologia , Citocinas/metabolismo , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Antígenos Comuns de Leucócito/metabolismo , Masculino , Pessoa de Meia-Idade , Proteômica/métodos , Regulação para Cima/genética , Regulação para Cima/imunologia , Adulto JovemRESUMO
INTRODUCTION: This work aimed to reveal the crucial role of Nell-1 in the angiogenic differentiation of human dental pulp stem cells (DPSCs) alone or co-cultured with human umbilical vein endothelial cell (HUVECs) in vitro and whether this molecule is involved in the pulp exposure model in vivo. METHODS: Immunofluorescence was conducted to ascertain the location of Nell-1 on DPSCs, HUVECs, and normal rat dental tissues. RT-PCR, Western blot, and ELISA were performed to observe the expression levels of angiogenic markers and determine the angiogenic differentiation of Nell-1 on DPSCs alone or co-cultured with HUVECs, as well as in vitro tube formation assay. Blood vessel number for all groups was observed and compared using immunohistochemistry by establishing a rat pulp exposure model. RESULTS: Nell-1 is highly expressed in the nucleus of DPSCs and HUVECs and is co-expressed with angiogenic markers in normal rat pulp tissues. Hence, Nell-1 can promote the angiogenic marker expression in DPSCs alone and co-cultured with other cells and can enhance angiogenesis in vitro as well as in the pulp exposure model. CONCLUSION: Nell-1 may play a positive role in the angiogenic differentiation of DPSCs.
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Beego is a traditional Chinese complete water-only fasting practice initially developed for spiritual purposes, later extending to physical fitness purposes. Beego notably includes a psychological induction component that includes meditation and abdominal breathing, light body exercise and ends with a specific gradual refeeding program before returning to a normal diet. Beego has regained its popularity in recent decades in China as a strategy for helping people in subhealthy conditions or with metabolic syndrome, but we are unaware of any studies examining the biological effects of this practice. To address this, we here performed a longitudinal study of beego comprising fasting (7 and 14 day cohorts) and a 7-day programmed refeeding phase. In addition to detecting improvements in cardiovascular physiology and selective reduction of blood pressure in hypertensive subjects, we observed that beego decreased blood triacylglycerol (TG) selectively in TG-high subjects and increased cholesterol in all subjects during fasting; however, the cholesterol levels were normalised after completion of the refeeding program. Strikingly, beego reduced platelet formation, activation, aggregation and degranulation, resulting in an alleviated thrombosis risk, yet maintained haemostasis by sustaining levels of coagulation factors and other haemostatic proteins. Mechanistically, we speculate that downregulation of G6B and MYL9 may influence the observed beego-mediated reduction in platelets. Fundamentally, our study supports that supervised beego reduces thrombosis risk without compromising haemostasis capacity. Moreover, our results support that beego under medical supervision can be implemented as non-invasive intervention for reducing thrombosis risk, and suggest several lines of intriguing inquiry for future studies about this fasting practice (http://www.chictr.org.cn/index.aspx, number, ChiCTR1900027451).
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Accumulative radiation exposure leads to hematopoietic or tissue aging. Whether hematopoietic stem cells (HSCs) are involved in lung damage repair in response to radiation remains controversial. The aim of this study is to identify if HSC can transdifferentiate to pneumonocytes for radiation-induced damage repair. To this end, HSCs from male RosamT/mG mice were isolated by fluorescence-activated cell sorting (FACS) and transplanted into lethally irradiated female CD45.1 mice. 4 months after transplantation, transplanted HSC was shown to repair the radiation-induced tissue damage, and donor-derived tdTomato (phycoerythrin, PE) red fluorescence cells and Ddx3y representing Y chromosome were detected exclusively in female recipient lung epithelial and endothelial cells. Co-localization of donor-derived cells and recipient lung tissue cells were observed by laser confocal microscopy and image flow cytometry. Furthermore, the results showed HSC transplantation replenished radiation-induced lung HSC depletion and the PE positive repaired lung epithelial cells were identified as donor HSC origin. The above data suggest that donor HSC may migrate to the injured lung of the recipient and some of them can be transdifferentiated to pneumonocytes to repair the injury caused by radiation.
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Células Epiteliais Alveolares/citologia , Transdiferenciação Celular/fisiologia , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/citologia , Lesões Experimentais por Radiação , Animais , Feminino , Transplante de Células-Tronco Hematopoéticas/métodos , Pulmão/efeitos da radiação , Masculino , CamundongosRESUMO
Atg7, a critical component of autophagy machinery, is essential for counteracting hematopoietic aging. However, the non-autophagic role of Atg7 on hematopoietic cells remains fundamentally unclear. In this study, we found that loss of Atg7, but not Atg5, another autophagy-essential gene, in the hematopoietic system reduces CD11b myeloid cellularity including CD11b+Ly6G+ and CD11b+Ly6G- populations in mouse bone marrow. Surprisingly, Atg7 deletion causes abnormally accumulated histone H3.1 to be overwhelmingly trapped in the cytoplasm in the CD11b+Ly6G-, but not the CD11b+Ly6G+ compartment. RNA profiling revealed extensively chaotic expression of the genes required in nucleosome assembly. Functional assays further indicated upregulated aging markers in the CD11b+Ly6G- population. Therefore, our study suggests that Atg7 is essential for maintaining proper nucleosome assembly and limiting aging in the bone marrow CD11b+Ly6G- population.
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Antígenos Ly/metabolismo , Proteína 7 Relacionada à Autofagia/genética , Antígeno CD11b/metabolismo , Células Mieloides/metabolismo , Nucleossomos/metabolismo , Animais , Proteína 7 Relacionada à Autofagia/metabolismo , Células da Medula Óssea/metabolismo , Camundongos , Camundongos KnockoutRESUMO
Autophagy suppresses mitochondrial metabolism to preserve hematopoietic stem cells (HSCs) in mice. However, the mechanism by which autophagy regulates hematopoietic aging, in particular in humans, has largely been unexplored. Here, we demonstrate that reduction of autophagy in both hematopoietic cells and their stem cells is associated with aged hematopoiesis in human population. Mechanistically, autophagy delays hematopoietic aging by activating the downstream expression of Sirt3, a key mitochondrial protein capable of rejuvenating blood. Sirt3 is the most abundant Sirtuin family member in HSC-enriched population, though it declines as the capacity for autophagy deteriorates with aging. Activation of autophagy upregulates Sirt3 in wild-type mice, whereas in autophagy-defective mice, Sirt3 expression is crippled in the entire hematopoietic hierarchy, but forced expression of Sirt3 in HSC-enriched cells reduces oxidative stress and prevents accelerated hematopoietic aging from autophagy defect. Importantly, the upregulation of Sirt3 by manipulation of autophagy is validated in human HSC-enriched cells. Thus, our results identify an autophagy-Sirt3 axis in regulating hematopoietic aging and suggest a possible interventional solution to human blood rejuvenation via activation of the axis.
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Células-Tronco Hematopoéticas/metabolismo , Sirtuína 3/sangue , Envelhecimento/sangue , Animais , Autofagia/fisiologia , Células-Tronco Hematopoéticas/citologia , Humanos , CamundongosRESUMO
Hematopoietic disorders are known to increase the risk of complications such as osteoporosis. However, a direct link between hematopoietic cellular disorders and osteoporosis has been elusive. Here, we demonstrate that the deterioration of hematopoietic autophagy is coupled with osteoporosis in humans. With a conditional mouse model in which autophagy in the hematopoietic system is disrupted by deletion of the Atg7 gene, we show that incapacitating hematopoietic autophagy causes bone loss and perturbs osteocyte homeostasis. Induction of osteoporosis, either by ovariectomy, which blocks estrogen secretion, or by injection of ferric ammonium citrate to induce iron overload, causes dysfunction in the hematopoietic stem and progenitor cells (HSPCs) similar to that found in autophagy-defective mice. Transcriptomic analysis of HSPCs suggests promotion of iron activity and inhibition of osteocyte differentiation and calcium metabolism by hematopoietic autophagy defect, while proteomic profiling of bone tissue proteins indicates disturbance of the extracellular matrix pathway that includes collagen family members. Finally, screening for expression of selected genes and an immunohistological assay identifies severe impairments in H vessels in the bone tissue, which results in disconnection of osteocytes from hematopoietic cells in the autophagy-defective mice. We therefore propose that hematopoietic autophagy is required for the integrity of H vessels that bridge blood and bone cells and that its deterioration leads to osteoporosis.