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Drought poses a major environmental threat to maize (Zea mays) production worldwide. Since maize is a monoecious plant, maize grain yield is dependent on the synchronous development of male and female inflorescences. When a drought episode occurs during flowering, however, an asynchronism occurs in the anthesis and silking interval (ASI) that results in significant yield losses. The underlying mechanism responsible for this asynchronism is still unclear. Here, we obtained a comprehensive development-drought transcriptome atlas of maize ears. Genes that function in cell expansion and growth were highly repressed by drought in 50 mm ears. Notably, an association study using a natural-variation population of maize revealed a significant relationship between the level of α-expansin4 (ZmEXPA4) expression and drought-induced increases in ASI. Furthermore, genetic manipulation of ZmEXPA4 expression using a drought-inducible promoter in developing maize ears reduced the ASI under drought conditions. These findings provide important insights into the molecular mechanism underlying the increase in ASI in maize ears subjected to drought and provide a promising strategy that can be used for trait improvement.
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Sequías , Proteínas de Plantas/genética , Zea mays/fisiología , Deshidratación , Regulación de la Expresión Génica de las Plantas , Inflorescencia/genética , Inflorescencia/fisiología , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas , Zea mays/genéticaRESUMEN
The roots of legume plant play a crucial role in nitrogen fixation. However, the transcriptomes of different cell types of legume root and their functions remain largely unknown. Here, we performed single-cell RNA sequencing and profiled more than 22,000 single cells from root tips of Lotus japonicus, a model species of legume. We identified seven clusters corresponding to seven major cell types, which were validated by in situ hybridization. Further analysis revealed regulatory programs including phytohormone and nodulation associated with specific cell types, and revealed conserved and diverged features for the cell types. Our results represent the first single-cell resolution transcriptome for legume root tips and a valuable resource for studying the developmental and physiological functions of various cell types in legumes.
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Lotus , Lotus/genética , Lotus/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Análisis de Expresión Génica de una Sola Célula , Simbiosis/genética , Fijación del Nitrógeno/genética , Nódulos de las Raíces de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/genéticaRESUMEN
BACKGROUND: Spinal cord injury (SCI) is a serious clinical condition that has pathological changes such as increased neuroinflammation and nerve tissue damage, which eventually manifests as fibrosis of the injured segment and the development of a spinal cord cavity leading to loss of function. Cell-based therapy, such as mesenchymal stem cells (MSCs) and neural stem cells (NSCs) are promising treatment strategies for spinal cord injury via immunological regulation and neural replacement respectively. However, therapeutic efficacy is rare reported on combined transplantation of MSC and NSC in acute mice spinal cord injury even the potential reinforcement might be foreseen. Therefore, this study was conducted to investigate the safety and efficacy of co-transplanting of MSC and NSC sheets into an SCI mice model on the locomotor function and pathological changes of injured spinal cord. METHODS: To evaluate the therapeutic effects of combination cells, acute SCI mice model were established and combined transplantation of hiPSC-NSCs and hMSCs into the lesion site immediately after the injury. Basso mouse scale was used to perform the open-field tests of hind limb motor function at days post-operation (dpo) 1, 3, 5, and 7 after SCI and every week after surgery. Spinal cord and serum samples were collected at dpo 7, 14, and 28 to detect inflammatory and neurotrophic factors. Hematoxylin-eosin (H&E) staining, masson staining and transmission electron microscopy were used to evaluate the morphological changes, fibrosis area and ultrastructure of the spinal cord. RESULT: M&N transplantation reduced fibrosis formation and the inflammation level while promoting the secretion of nerve growth factor and brain-derived neurotrophic factor. We observed significant reduction in damaged tissue and cavity area, with dramatic improvement in the M&N group. Compared with the Con group, the M&N group exhibited significantly improved behaviors, particularly limb coordination. CONCLUSION: Combined transplantation of hiPSC-NSC and hMSC could significantly ameliorate neuroinflammation, promote neuroregeneration, and decrease spinal fibrosis degree in safe and effective pattern, which would be indicated as a novel potential cell treatment option.
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Células Madre Pluripotentes Inducidas , Traumatismos de la Médula Espinal , Animales , Ratones , Enfermedades Neuroinflamatorias , Traumatismos de la Médula Espinal/terapia , Modelos Animales de Enfermedad , FibrosisRESUMEN
How to simultaneously utilize photogenerated electrons and holes still remains a critical challenge in the field of artificial photosynthesis, especially in the process of photocatalytic hydrogen (H2) evolution coupled with biomass oxidation to value-added chemicals. Herein, a series-parallel photocatalyst (Cu NPs/CdS/In2O3) that can intrinsically regulate the transfer of photogenerated carriers is ingeniously designed for photocatalytic H2 evolution synergized with furfural alcohol (FFA) selective oxidation to furfural (FF). Accordingly, the desired H2 and FF evolution rates with near 100% selectivity toward FF are achieved on Cu NPs/CdS/In2O3 in a sealed atmospheric system. Experimental and theoretical analyses confirm that the localized surface plasmon resonance (LSPR) effect induced by Cu NPs accelerates the reduction of protons (H+) to H2 efficiently, while the photogenerated holes from In2O3 preferentially activate the α-C-H bond of FFA adsorbed on Lewis acid sites to generate FF. This work provides a reference for regulating the transfer of photogenerated carriers for H2 evolution coupled with FF synthesis.
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BACKGROUND: Diabetic cardiomyopathy (DCM) is a serious health-threatening complication of diabetes mellitus characterized by myocardial fibrosis and abnormal cardiac function. Human umbilical cord mesenchymal stromal cells (hUC-MSCs) are a potential therapeutic tool for DCM and myocardial fibrosis via mechanisms such as the regulation of microRNA (miRNA) expression and inflammation. It remains unclear, however, whether hUC-MSC therapy has beneficial effects on cardiac function following different durations of diabetes and which mechanistic aspects of DCM are modulated by hUC-MSC administration at different stages of its development. This study aimed to investigate the therapeutic effects of intravenous administration of hUC-MSCs on DCM following different durations of hyperglycemia in an experimental male model of diabetes and to determine the effects on expression of candidate miRNAs, target mRNA and inflammatory mediators. METHODS: A male mouse model of diabetes was induced by multiple low-dose streptozotocin injections. The effects on severity of DCM of intravenous injections of hUC-MSCs and saline two weeks previously were compared at 10 and 18 weeks after diabetes induction. At both time-points, biochemical assays, echocardiography, histopathology, polymerase chain reaction (PCR), immunohistochemistry and enzyme-linked immunosorbent assays (ELISA) were used to analyze blood glucose, body weight, cardiac structure and function, degree of myocardial fibrosis and expression of fibrosis-related mRNA, miRNA and inflammatory mediators. RESULTS: Saline-treated diabetic male mice had impaired cardiac function and increased cardiac fibrosis after 10 and 18 weeks of diabetes. At both time-points, cardiac dysfunction and fibrosis were improved in hUC-MSC-treated mice. Pro-fibrotic indicators (α-SMA, collagen I, collagen III, Smad3, Smad4) were reduced and anti-fibrotic mediators (FGF-1, miRNA-133a) were increased in hearts of diabetic animals receiving hUC-MSCs compared to saline. Increased blood levels of pro-inflammatory cytokines (IL-6, TNF, IL-1ß) and increased cardiac expression of IL-6 were also observed in saline-treated mice and were reduced by hUC-MSCs at both time-points, but to a lesser degree at 18 weeks. CONCLUSION: Intravenous injection of hUC-MSCs ameliorated key functional and structural features of DCM in male mice with diabetes of shorter and longer duration. Mechanistically, these effects were associated with restoration of intra-myocardial expression of miRNA-133a and its target mRNA COL1AI as well as suppression of systemic and localized inflammatory mediators.
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Diabetes Mellitus Experimental , Cardiomiopatías Diabéticas , Fibrosis , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , MicroARNs , Miocardio , Cordón Umbilical , Animales , Humanos , Masculino , Ratones , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Experimental/metabolismo , Cardiomiopatías Diabéticas/terapia , Cardiomiopatías Diabéticas/metabolismo , Cardiomiopatías Diabéticas/patología , Cardiomiopatías Diabéticas/genética , Fibrosis/terapia , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/metabolismo , Ratones Endogámicos C57BL , MicroARNs/genética , MicroARNs/metabolismo , Miocardio/metabolismo , Miocardio/patología , Cordón Umbilical/citología , Cordón Umbilical/metabolismoRESUMEN
BACKGROUND AND AIMS: Mesenchymal stromal cells (MSCs) a potentially effective disease-modulating therapy for diabetic nephropathy (DN) but their clinical translation has been hampered by incomplete understanding of the optimal timing of administration and in vivo mechanisms of action. This study aimed to elucidate the reno-protective potency and associated mechanisms of single intravenous injections of human umbilical cord-derived MSCs (hUC-MSCs) following shorter and longer durations of diabetes. METHODS: A streptozotocin (STZ)-induced model of diabetes and DN was established in C57BL/6 mice. In groups of diabetic animals, human (h)UC-MSCs or vehicle were injected intravenously at 8 or 16 weeks after STZ along with vehicle-injected non-diabetic animals. Diabetes-related kidney abnormalities was analyzed 2 weeks later by urine and serum biochemical assays, histology, transmission electron microscopy and immunohistochemistry. Serum concentrations of pro-inflammatory and pro-fibrotic cytokines were quantified by ELISA. The expression of autophagy-related proteins within the renal cortices was investigated by immunoblotting. Bio-distribution of hUC-MSCs in kidney and other organs was evaluated in diabetic mice by injection of fluorescent-labelled cells. RESULTS: Compared to non-diabetic controls, diabetic mice had increases in urine albumin creatinine ratio (uACR), mesangial matrix deposition, podocyte foot process effacement, glomerular basement membrane thickening and interstitial fibrosis as well as reduced podocyte numbers at both 10 and 18 weeks after STZ. Early (8 weeks) hUC-MSC injection was associated with reduced uACR and improvements in multiple glomerular and renal interstitial abnormalities as well as reduced serum IL-6, TNF-α, and TGF-ß1 compared to vehicle-injected animals. Later (16 weeks) hUC-MSC injection also resulted in reduction of diabetes-associated renal abnormalities and serum TGF-ß1 but not of serum IL-6 and TNF-α. At both time-points, the kidneys of vehicle-injected diabetic mice had higher ratio of p-mTOR to mTOR, increased abundance of p62, lower abundance of ULK1 and Atg12, and reduced ratio of LC3B to LC3A compared to non-diabetic animals, consistent with diabetes-associated suppression of autophagy. These changes were largely reversed in the kidneys of hUC-MSC-injected mice. In contrast, neither early nor later hUC-MSC injection had effects on blood glucose and body weight of diabetic animals. Small numbers of CM-Dil-labeled hUC-MSCs remained detectable in kidneys, lungs and liver of diabetic mice at 14 days after intravenous injection. CONCLUSIONS: Single intravenous injections of hUC-MSCs ameliorated glomerular abnormalities and interstitial fibrosis in a mouse model of STZ-induced diabetes without affecting hyperglycemia, whether administered at relatively short or longer duration of diabetes. At both time-points, the reno-protective effects of hUC-MSCs were associated with reduced circulating TGF-ß1 and restoration of intra-renal autophagy.
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Diabetes Mellitus Experimental , Nefropatías Diabéticas , Riñón/anomalías , Células Madre Mesenquimatosas , Anomalías Urogenitales , Humanos , Animales , Ratones , Ratones Endogámicos C57BL , Nefropatías Diabéticas/terapia , Inyecciones Intravenosas , Factor de Crecimiento Transformador beta1 , Diabetes Mellitus Experimental/terapia , Interleucina-6 , Factor de Necrosis Tumoral alfa , Autofagia , Fibrosis , Serina-Treonina Quinasas TORRESUMEN
BACKGROUND AND PURPOSE: Isoxazole 9 (ISX9) is a neurogenesis-promoting small molecule compound that can up-regulate the expression of NeuroD1 and induce differentiation of neuronal, cardiac and islet endocrine progenitors. So far, the molecular mechanisms underlying the action of ISX9 still remain elusive. EXPERIMENTAL APPROACH: To identify a novel agonist of the Wnt/ß-catenin, a cell-based SuperTOPFlash reporter system was used to screen known-compound libraries. An activation effect of ISX9 on the Wnt/ß-catenin pathway was analysed with the SuperTOPFlash or SuperFOPFlash reporter system. Effects of ISX9 on Axin1/LRP6 interaction were examined using a mammalian two-hybrid system, co-immunoprecipitation, microscale thermophoresis, emission spectra and mass spectrometry assays. The expression of Wnt target and stemmness marker genes were evaluated with real-time PCR and immunoblotting. In vivo hair regeneration abilities of ISX9 were analysed by immunohistochemical staining, real-time PCR and immunoblotting in hair regrowth model using C57BL/6J mice. KEY RESULTS: In this study, ISX9 was identified as a novel agonist of the Wnt/ß-catenin pathway. ISX9 targeted Axin1 by covalently binding to its N-terminal region and potentiated the LRP6-Axin1 interaction, thereby resulting in the stabilization of ß-catenin and up-regulation of Wnt target genes and stemmness marker genes. Moreover, the topical application of ISX9 markedly promoted hair regrowth in C57BL/6J mice and induced hair follicle transition from telogen to anagen via enhancing Wnt/ß-catenin pathway. CONCLUSIONS AND IMPLICATIONS: Taken together, our study unravelled that ISX9 could activate Wnt/ß-catenin signalling by potentiating the association between LRP6 and Axin1, and may be a promising therapeutic agent for alopecia treatment.
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Vía de Señalización Wnt , beta Catenina , Ratones , Animales , Proteína Axina/genética , Proteína Axina/metabolismo , Proteína Axina/farmacología , beta Catenina/metabolismo , Ratones Endogámicos C57BL , Cabello , Mamíferos/metabolismoRESUMEN
Chloroxylenol is the active ingredient of the antibacterial agent Dettol. The anticancer effect and underlying mechanisms of this compound and other common antimicrobial agents have not been clearly elucidated. In the present study, the effects of chloroxylenol, benzalkonium chloride, benzethonium chloride, triclosan and triclocarban on ßcateninmediated Wnt signaling in colorectal cancer were evaluated using the SuperTOPFlash reporter assay. It was demonstrated that chloroxylenol, but not the other antimicrobial agents tested, inhibited the Wnt/ßcatenin signaling pathway by decreasing the nuclear translocation of ßcatenin and disrupting ßcatenin/Tcell factor 4 complex, which resulted in the downregulation of the Wnt target genes Axin2, Survivin and Leucinerich G proteincoupled receptor5. Chloroxylenol effectively inhibited the viability, proliferation, migration and invasion, and sphere formation, and induced apoptosis in HCT116 and SW480 cells. Notably, chloroxylenol attenuated the growth of colorectal cancer in the MC38 cell xenograft model and inhibited organoid formation by the patientderived cells. Chloroxylenol also demonstrated inhibitory effects on the stemness of colorectal cancer cells. The results of the present study demonstrated that chloroxylenol could exert antitumor activities in colorectal cancer by targeting the Wnt/ßcatenin signaling pathway, which provided an insight into its therapeutic potential as an anticancer agent.
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Antiinfecciosos , Neoplasias Colorrectales , Humanos , beta Catenina , Vía de Señalización Wnt , Neoplasias Colorrectales/tratamiento farmacológicoRESUMEN
BACKGROUND: Phase I clinical trials play an important role in the follow-up clinical trials and even the drug registration and marketing. However, the screening success ratio in phase I clinical trials is low, and the screening process of the trials consumes a significant amount of human and material resources, but the results are unsatisfactory. At present, there is no large sample data analysis for screening failure in phase I clinical trials. It is therefore urgent to find the reasons for screening failure in phase I clinical trials. METHODS: A total of 1,058 healthy volunteers who failed the screening in 11 phase I clinical trials were retrospectively collected from October 2018 to June 2021 in Cangzhou Central Hospital. Data on all participants who failed screening for the study were analyzed (descriptive analysis) and reasons for their non-randomization were classified, as well as the differences of main screening failures between four years. RESULTS: A total of 1,466 healthy volunteers were enrolled in the 11 trials, and among them 1,058 subjects failed the screening. The total screening success ratio of our study was only 27.8%, the highest being 38.5% and the lowest being 18.2%. The top 3 reasons for non-randomization were abnormalities in blood biochemistry tests (23.3%), vital sign examination (19.3%), and electrocardiogram (ECG) (16.6%). Abnormal blood biochemistry was the main reason between 2019 and 2021, except for 2018 in which it was the second reason. CONCLUSIONS: Screening failure is a burdensome issue which various clinical trial sites must contend with. Investigators can still take some effective measures by strengthening the in-depth understanding of informed consent, paying attention to the quality of test samples, a correcting definition of no clinical significance (NCS). Also, low-cost and non-invasive examinations can be arranged first to better protect the volunteers and reduce the screening costs of clinical trials. To our delight, we find people's attention to the annual physical examination may help to screen healthy volunteers. Overall, this study shows that it is crucial and professional to develop a screening plan to minimize the resultant impact on timelines and budgets of phase I clinical trials enrolling healthy volunteers.
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Voluntarios Sanos , Consentimiento Informado , Tamizaje Masivo , Ensayos Clínicos Fase I como Asunto , Humanos , Selección de Paciente , Estudios RetrospectivosRESUMEN
With the highest incidence, breast cancer is the leading cause of cancer deaths among women in the world. Tumor metastasis is the major contributor of high mortality in breast cancer, and the existence of cancer stem cells (CSCs) has been proven to be the cause of tumor metastasis. CSCs are a small proportion of tumor cells, and they are associated with self-renewal and tumorigenic potential. Given the significance of CSCs in tumor initiation, expansion, relapse, resistance, and metastasis, studies should investigate and discover effective anticancer agents that can not only inhibit the proliferation of differentiated tumor cells but also reduce the tumorigenic capability of CSCs. Thus, new therapies must be discovered to treat and prevent this severely hazardous disease of human beings. The success of platinum complexes in cancer treatment has laid the basic foundation for the utilization of metal complexes in the treatment of malignant cancers, in particular the highly aggressive triple-negative breast cancer. Importantly, metal complexes currently have diverse and versatile competences in the therapeutic targeting of CSCs. The anti-CSC properties provide a strong impetus for the development of novel metal-based compounds for the targeting of CSCs and treatment of chemotherapy-resistant and relapsed tumors. In this review, we provide the latest advances in metal complexes including platinum, ruthenium, osmium, iridium, manganese, cobalt, nickel, copper, zinc, palladium, and tin complexes against breast CSCs obtained over the past decade, with pertinent literature including those published until 2021.
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Neoplasias de la MamaRESUMEN
Potocki-Lupski syndrome (PTLS; MIM 610883) is a neurodevelopmental disorder associated with a 3.7 Mb copy number variant (CNV) duplication, locating in chromosome 17p11.2. (Soler-Alfonso et al., 2011). Here, a human induced pluripotent stem cell (iPSC) line was derived from the peripheral blood mononuclear cells of a 5-year-old child suffering Potocki-Lupski syndrome. The generated iPSCs were integration-free, had the 17p11.2 3.7 Mb CNV duplication with no additional genomic alterations, a stable karyotype, expressed pluripotency stem cell markers and could differentiate towards the three germ layers in vitro. Patient's derived iPSCs are a valuable resource for in vitro modeling of 17p11.2 microduplication induced Potocki-Lupski syndrome.
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Células Madre Pluripotentes Inducidas , Anomalías Múltiples , Preescolar , Trastornos de los Cromosomas , Duplicación Cromosómica , Hibridación Genómica Comparativa , Humanos , Leucocitos MononuclearesRESUMEN
In this study, skin biopsy was collected from a healthy 48-year old male donor with informed consent, and the fibroblasts were isolated from the dermal explant cultures. Here, a human induced pluripotent stem cell (iPSC) line was derived from the fibroblasts using the reprogramming four Yamanaka factors (Oct3/4, Sox2, Klf4, c-Myc). The generated iPSCs were integration-free, displayed the normal karyotype, expressed pluripotency markers and demonstrated trilineage differentiation potential in vitro. This iPSC model will be useful for investigating physiological processes, drug validation as well as a control in pathological mechanistic studies.
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Células Madre Pluripotentes Inducidas , Diferenciación Celular , Reprogramación Celular , Fibroblastos , Humanos , Factor 4 Similar a Kruppel , Masculino , Persona de Mediana Edad , PielRESUMEN
Apolipoprotein E (ApoE) is a lipid-binding protein with ε2, ε3, and ε4 allelic variants in human. The ε4 isoform (ApoE4) is the strongest genetic risk factor for the late-onset form of Alzheimer's disease (AD), and is also associated with multiple neurological disorders, multiple sclerosis, and cerebrovascular disease. Here, induced pluripotent stem cells were derived from the peripheral blood mononuclear cells of a 70-year-old male donor with APOE-ε4/ε4 alleles background to explore pathogenesis and screen potential treatment methods in neurodegenerative diseases. In the newly-developed induced pluripotent stem cell line, the pluripotent markers were well expressed. In addition, the generated cells displayed a normal karyotype and have differentiation potential.
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Enfermedad de Alzheimer , Células Madre Pluripotentes Inducidas , Anciano , Alelos , Enfermedad de Alzheimer/genética , Apolipoproteína E4/genética , Apolipoproteínas E/genética , Genotipo , Humanos , Leucocitos Mononucleares , MasculinoRESUMEN
BACKGROUND: Spinal cord injury (SCI) is a common disease that results in motor and sensory disorders and even lifelong paralysis. The transplantation of stem cells, such as embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), mesenchymal stem cells (MSCs), or subsequently generated stem/progenitor cells, is predicted to be a promising treatment for SCI. In this study, we aimed to investigate effect of human iPSC-derived neural stem cells (hiPSC-NSCs) and umbilical cord-derived MSCs (huMSCs) in a mouse model of acute SCI. METHODS: Acute SCI mice model were established and were randomly treated as phosphate-buffered saline (PBS) (control group), repaired with 1 × 105 hiPSC-NSCs (NSC group), and 1 × 105 huMSCs (MSC group), respectively, in a total of 54 mice (n = 18 each). Hind limb motor function was evaluated in open-field tests using the Basso Mouse Scale (BMS) at days post-operation (dpo) 1, 3, 5, and 7 after spinal cord injury, and weekly thereafter. Spinal cord and serum samples were harvested at dpo 7, 14, and 21. Haematoxylin-eosin (H&E) staining and Masson staining were used to evaluate the morphological changes and fibrosis area. The differentiation of the transplanted cells in vivo was evaluated with immunohistochemical staining. RESULTS: The hiPSC-NSC-treated group presented a significantly smaller glial fibrillary acidic protein (GFAP) positive area than MSC-treated mice at all time points. Additionally, MSC-transplanted mice had a similar GFAP+ area to mice receiving PBS. At dpo 14, the immunostained hiPSC-NSCs were positive for SRY-related high-mobility-group (HMG)-box protein-2 (SOX2). Furthermore, the transplanted hiPSC-NSCs differentiated into GFAP-positive astrocytes and beta-III tubulin-positive neurons, whereas the transplanted huMSCs differentiated into GFAP-positive astrocytes. In addition, hiPSC-NSC transplantation reduced fibrosis formation and the inflammation level. Compared with the control or huMSC transplanted group, the group with transplantation of hiPSC-NSCs exhibited significantly improved behaviours, particularly limb coordination. CONCLUSIONS: HiPSC-NSCs promote functional recovery in mice with acute SCI by replacing missing neurons and attenuating fibrosis, glial scar formation, and inflammation.
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Células Madre Pluripotentes Inducidas , Células-Madre Neurales , Traumatismos de la Médula Espinal , Animales , Diferenciación Celular , Células Madre Pluripotentes Inducidas/trasplante , Ratones , Células-Madre Neurales/trasplante , Recuperación de la Función , Médula Espinal , Traumatismos de la Médula Espinal/terapiaRESUMEN
Alzheimer's disease (AD) is a neurodegenerative disease and a common cause of dementia among elderly individuals. The disease is characterized by progressive cognitive decline, accumulation of senile amyloid plaques and neurofibrillary tangles, oxidative stress, and inflammation. Human-derived cell models of AD are scarce, and over the years, non-human-derived models have been developed to recapitulate clinical AD, investigate the disease's pathogenesis and develop therapies for the disease. Several pharmacological compounds have been developed for AD based on findings from non-human-derived cell models; however, these pharmacological compounds have failed at different phases of clinical trials. This necessitates the application of human-derived cell models, such as induced pluripotent stem cells (iPSCs) in their optimized form in AD mechanistic studies and preclinical drug testing. This review provides an overview of AD and iPSCs. The AD-relevant phenotypes of iPSC-derived AD brain cells and the usefulness of iPSCs in AD are highlighted. Finally, the various recommendations that have been made to enhance iPSC/AD modelling are discussed.
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Enfermedad de Alzheimer , Células Madre Pluripotentes Inducidas , Enfermedades Neurodegenerativas , Anciano , Encéfalo , Humanos , Placa AmiloideRESUMEN
BACKGROUND: Maize (Zea mays L.) is the third most consumed grain in the world and improving maize yield is of great importance of the world food security, especially under global climate change and more frequent severe droughts. Due to the limitation of phenotyping methods, most current studies only focused on the responses of phenotypes on certain key growth stages. Although light detection and ranging (lidar) technology showed great potential in acquiring three-dimensional (3D) vegetation information, it has been rarely used in monitoring maize phenotype dynamics at an individual plant level. RESULTS: In this study, we used a terrestrial laser scanner to collect lidar data at six growth stages for 20 maize varieties under drought stress. Three drought-related phenotypes, i.e., plant height, plant area index (PAI) and projected leaf area (PLA), were calculated from the lidar point clouds at the individual plant level. The results showed that terrestrial lidar data can be used to estimate plant height, PAI and PLA at an accuracy of 96%, 70% and 92%, respectively. All three phenotypes showed a pattern of first increasing and then decreasing during the growth period. The high drought tolerance group tended to keep lower plant height and PAI without losing PLA during the tasseling stage. Moreover, the high drought tolerance group inclined to have lower plant area density in the upper canopy than the low drought tolerance group. CONCLUSION: The results demonstrate the feasibility of using terrestrial lidar to monitor 3D maize phenotypes under drought stress in the field and may provide new insights on identifying the key phenotypes and growth stages influenced by drought stress.
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The aim of the present study was to assess the effects of sprouty homolog 2 (SPRY2) gene regulation by miR-21 on the occurrence, development and tumor metastasis in multiple myeloma (MM). The miR-21 expression lentiviral vector (LV)-anti-miR-21 and a liposome transfection method were used to screen MM cell lines with stable silent SPRY2. Real-time quantitative polymerase chain reaction (PCR) and western blot analyses were used to detect SPRY2 expression and miR-21 protein expression levels. An MTT assay was used to assess cell proliferation. Flow cytometry was used for analysis of cell cycle. A scratch test/wound healing assay was used to detect the cell migration ability. A Transwell assay was used to detect the cell invasion ability. Real-time quantitative PCR and western blot analysis showed that in the MM cell lines with high endogenous miR-21 expression (RPMI8226 and KM3), SPRY2 expression was significantly lower. Conversely, in the U266 cell line with low endogenous miR-21 expression, SPRY2 expression was significantly higher, and the gray values of miR-21 and SPRY2 protein in the respective cell lines showed statistically significant differences (P<0.01). Following transfection of U266 cells, the expression of miR-21 in the U266/LV-anti-miR21 lentiviral multiplicity of infection (MOI) 20 group and -MOI 40 group decreased significantly compared with that in the untransfected U266 group (P<0.05). SPRY2 protein expression in U266 cells transfected with miR-21 mimics was significantly reduced compared with that in the non-transfected (untreated) group and the negative control-transfected group (P<0.01). An MTT assay showed that compared with the non-transfected and negative control groups, the cell growth rate as well as the proliferation rate were significantly decreased in the transfection group 48, 72 and 96 h after transfection (P<0.01). Flow cytometric analysis showed that 48 and 72 h after transfection of U266 cells with miR-21 mimics, the apoptotic rates were (24.7 ± 1.97 and 38.6 ± 1.56%) in the U266 group, (27.3 ± 1.72 and 37.3 ± 1.59%) in the siRNA group and (12.7 ± 1.27 and 22.1 ± 1.63%) in the U266/miR-21 group. Compared with the two control groups, the apoptotic rate in the U266/miR-21 group was significantly decreased and the G0/G1 phase cell population was significantly reduced (P<0.05). Scratch experiments showed that the cell migration ability was significantly reduced in the transfection group 24 and 48 h after transfection (P<0.05). A Transwell invasion assay confirmed that the number of U266 cells which migrated through a Matrigel-covered polyphosphate membrane significantly decreased in the transfection group 24 and 48 h after transfection. The cell-penetrating ability was also significantly decreased (P<0.05). In conclusion, the downregulation of SPRY2 gene expression mediated by miR-21 promotes the proliferation and invasion of MM cells in vitro, suggesting that miR-21 may be a novel potential molecular therapeutic target in the treatment of MM.
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Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas de la Membrana/metabolismo , MicroARNs/metabolismo , Apoptosis , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Regulación hacia Abajo , Humanos , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas de la Membrana/antagonistas & inhibidores , Proteínas de la Membrana/genética , MicroARNs/antagonistas & inhibidores , MicroARNs/genética , Mieloma Múltiple/metabolismo , Mieloma Múltiple/patología , Oligonucleótidos Antisentido/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , TransfecciónRESUMEN
The aim of the present study was to investigate the expression level of microRNA 21 (miR21) in the peripheral blood of patients with multiple myeloma (MM) and to investigate the correlation between miR21 and sprouty homolog 2 (SPRY2) gene expression levels in MM. A total of 30 patients with MM, 15 with monoclonal gammopathy of undetermined significance (MGUS) and 20 normal control (NC) outpatients were selected for the detection of miR21 and SPRY2 expression using reverse transcription-quantitative polymerase chain reaction. In addition, western blot analysis was performed to detect the expression of miR21 and SPRY2 in MM cell lines. The expression of miR21 in U266 cells following lipofectamine transfection of fluorescencelabeled miR21 mimic/inhibitor was observed using a fluorescence microscope and the expression level of SPRY2 in the miR21 mimic/inhibitortransfected U266 cells was detected using western blot analysis. The miR21 expression level in the circulating serum of the MM patient group was significantly higher (P<0.01) than that of the MGUS and NC groups. The MM cell lines with high endogenous miR21 expression exhibited an expression level of SPRY2 that was significantly lower than that in the MM cells with low endogenous miR21 expression. The transfection efficiency of fluorescencelabeled miR21 mimic/inhibitor was >90%. Compared with the miR21 expression level in untreated U266 cells (0.82±0.13), the expression level of miR21 was increased by 120.2fold in miR21 mimictransfected cells (98.6±14.2; P<0.001) and was decreased by 61.9% in the miR21 inhibitortransfected cells (0.37±0.06; P<0.05). The grayscale value of protein bands demonstrated that SPRY2 protein expression significantly decreased in miR21 mimictransfected U266 cells compared with that in the inhibitortransfected, siRNAtransfected and untreated cells (P<0.01). miR21 may represent a negative regulator involved in the downregulation of SPRY2 in MM. miR21 is closely associated with the pathogenesis, progression and prognosis of MM and may thus be used as an indicator of poor MM prognosis.