ABSTRACT
Hutchinson-Gilford progeria syndrome (HGPS or progeria) is typically caused by a dominant-negative Câ¢G-to-Tâ¢A mutation (c.1824 C>T; p.G608G) in LMNA, the gene that encodes nuclear lamin A. This mutation causes RNA mis-splicing that produces progerin, a toxic protein that induces rapid ageing and shortens the lifespan of children with progeria to approximately 14 years1-4. Adenine base editors (ABEs) convert targeted Aâ¢T base pairs to Gâ¢C base pairs with minimal by-products and without requiring double-strand DNA breaks or donor DNA templates5,6. Here we describe the use of an ABE to directly correct the pathogenic HGPS mutation in cultured fibroblasts derived from children with progeria and in a mouse model of HGPS. Lentiviral delivery of the ABE to fibroblasts from children with HGPS resulted in 87-91% correction of the pathogenic allele, mitigation of RNA mis-splicing, reduced levels of progerin and correction of nuclear abnormalities. Unbiased off-target DNA and RNA editing analysis did not detect off-target editing in treated patient-derived fibroblasts. In transgenic mice that are homozygous for the human LMNA c.1824 C>T allele, a single retro-orbital injection of adeno-associated virus 9 (AAV9) encoding the ABE resulted in substantial, durable correction of the pathogenic mutation (around 20-60% across various organs six months after injection), restoration of normal RNA splicing and reduction of progerin protein levels. In vivo base editing rescued the vascular pathology of the mice, preserving vascular smooth muscle cell counts and preventing adventitial fibrosis. A single injection of ABE-expressing AAV9 at postnatal day 14 improved vitality and greatly extended the median lifespan of the mice from 215 to 510 days. These findings demonstrate the potential of in vivo base editing as a possible treatment for HGPS and other genetic diseases by directly correcting their root cause.
Subject(s)
Adenine/metabolism , Gene Editing/methods , Mutation , Progeria/genetics , Progeria/therapy , Alleles , Alternative Splicing , Animals , Aorta/pathology , Base Pairing , Child , DNA/genetics , Disease Models, Animal , Female , Fibroblasts/metabolism , Humans , Lamin Type A/chemistry , Lamin Type A/genetics , Lamin Type A/metabolism , Longevity , Male , Mice , Mice, Transgenic , Mutant Proteins/chemistry , Mutant Proteins/genetics , Mutant Proteins/metabolism , Progeria/pathology , RNA/geneticsABSTRACT
BACKGROUND: It is documented that mesenchymal stem cells (MSCs) secrete extracellular vesicles (EVs) to modulate subarachnoid hemorrhage (SAH) development. miR-140-5p expression has been detected in MSC-derived EVs, while the mechanism of MSC-derived EVs containing miR-140-5p in SAH remains unknown. We aim to fill this void by establishing SAH mouse models and extracting MSCs and MSC-EVs. METHODS: After ALK5 was silenced in SAH mice, neurological function was evaluated, neuron apoptosis was detected by TdT-mediated dUTP-biotin nick end labeling with NeuN staining, and expression of serum inflammatory factors (interleukin-6, interleukin-1ß, and tumor necrosis factor-α) was determined by enzyme-linked immunosorbent assay. The effect of ALK5 on NOX2 expression was assessed by western-blot analysis. Targeting the relationship between miR-140-5p and ALK5 was evaluated by dual luciferase assay. Following extraction of MSCs and MSC-EVs, EVs and miR-140-5p were labeled by PKH67 and Cy3, respectively, to identify the transferring of miR-140-5p by MSC-EVs. SAH mice were treated with EVs from miR-140-5p mimic/inhibitor-transfected MSCs to detect effects of MSC-EV-miR-140-5p on brain injury and microglial polarization. RESULTS: ALK5 silencing increased the neurological score and reduced neuron apoptosis and neuroinflammation in SAH mice. ALK5 silencing inhibited M1 microglia activation by inactivating NOX2. ALK5 was a target gene of miR-140-5p. MSC-derived EVs contained miR-140-5p and transferred miR-140-5p into microglia. MSC-EV-delivered miR-140-3p reduced ALK5 expression to contribute to repression of brain injury and M1 microglia activation in SAH mice. CONCLUSIONS: MSC-derived EVs transferred miR-140-5p into microglia to downregulate ALK5 and NOX2, thus inhibiting M1 microglia activation in SAH mice.
Subject(s)
Brain Injuries , Extracellular Vesicles , Mesenchymal Stem Cells , MicroRNAs , Subarachnoid Hemorrhage , Animals , Brain Injuries/metabolism , Extracellular Vesicles/metabolism , Mesenchymal Stem Cells/metabolism , Mice , MicroRNAs/genetics , MicroRNAs/metabolism , Microglia/metabolism , Subarachnoid Hemorrhage/metabolism , Subarachnoid Hemorrhage/therapyABSTRACT
Telomerase is an enzymatic ribonucleoprotein complex that acts as a reverse transcriptase in the elongation of telomeres. Telomerase activity is well documented in embryonic stem cells and the vast majority of tumor cells, but its role in somatic cells remains to be understood. Here, we report an unexpected function of telomerase during cellular senescence and tumorigenesis. We crossed Tert heterozygous knockout mice (mTert+/- ) for 26 generations, during which time there was progressive shortening of telomeres, and obtained primary skin fibroblasts from mTert+/+ and mTert-/- progeny of the 26th cross. As a consequence of insufficient telomerase activities in prior generations, both mTert+/+ and mTert-/- fibroblasts showed comparable and extremely short telomere length. However, mTert-/- cells approached cellular senescence faster and exhibited a significantly higher rate of malignant transformation than mTert+/+ cells. Furthermore, an evident up-regulation of telomerase reverse-transcriptase (TERT) expression was detected in mTert+/+ cells at the presenescence stage. Moreover, removal or down-regulation of TERT expression in mTert+/+ and human primary fibroblast cells via CRISPR/Cas9 or shRNA recapitulated mTert-/- phenotypes of accelerated senescence and transformation, and overexpression of TERT in mTert-/- cells rescued these phenotypes. Taking these data together, this study suggests that TERT has a previously underappreciated, protective role in buffering senescence stresses due to short, dysfunctional telomeres, and preventing malignant transformation.
Subject(s)
Cell Transformation, Neoplastic/genetics , Cellular Senescence/genetics , Telomerase/genetics , Telomerase/metabolism , Animals , Cell Cycle/genetics , Cells, Cultured , Fibroblasts/pathology , Gene Expression , Gene Expression Regulation , Gene Knockdown Techniques , Humans , Mice , Mice, Inbred C57BL , Mice, Knockout , Phenotype , Telomere/pathologyABSTRACT
Hutchinson-Gilford progeria syndrome (HGPS) is a detrimental premature aging disease caused by a point mutation in the human LMNA gene. This mutation results in the abnormal accumulation of a truncated pre-lamin A protein called progerin. Among the drastically accelerated signs of aging in HGPS patients, severe skin phenotypes such as alopecia and sclerotic skins always develop with the disease progression. Here, we studied the HGPS molecular mechanisms focusing on early skin development by differentiating patient-derived induced pluripotent stem cells (iPSCs) to a keratinocyte lineage. Interestingly, HGPS iPSCs showed an accelerated commitment to the keratinocyte lineage than the normal control. To study potential signaling pathways that accelerated skin development in HGPS, we investigated the WNT pathway components during HGPS iPSCs-keratinocytes induction. Surprisingly, despite the unaffected ß-catenin activity, the expression of a critical WNT transcription factor LEF1 was diminished from an early stage in HGPS iPSCs-keratinocytes differentiation. A chromatin immunoprecipitation (ChIP) experiment further revealed strong bindings of LEF1 to the early-stage epithelial developmental markers K8 and K18 and that the LEF1 silencing by siRNA down-regulates the K8/K18 transcription. During the iPSCs-keratinocytes differentiation, correction of HGPS mutation by Adenine base editing (ABE), while in a partial level, rescued the phenotypes for accelerated keratinocyte lineage-commitment. ABE also reduced the cell death in HGPS iPSCs-derived keratinocytes. These findings brought new insight into the molecular basis and therapeutic application for the skin abnormalities in HGPS.
Subject(s)
Induced Pluripotent Stem Cells , Lymphoid Enhancer-Binding Factor 1 , Progeria , Cell Differentiation , Humans , Induced Pluripotent Stem Cells/cytology , Induced Pluripotent Stem Cells/metabolism , Keratinocytes/cytology , Keratinocytes/metabolism , Lamin Type A/genetics , Lamin Type A/metabolism , Lymphoid Enhancer-Binding Factor 1/genetics , Lymphoid Enhancer-Binding Factor 1/metabolism , Progeria/genetics , Progeria/metabolism , Wnt Signaling PathwayABSTRACT
Hutchinson-Gilford progeria syndrome (HGPS) is a severe human premature aging disorder caused by a lamin A mutant named progerin. Death occurs at a mean age of 13 y from cardiovascular problems. Previous studies revealed loss of vascular smooth muscle cells (SMCs) in the media of large arteries in a patient with HGPS and two mouse models, suggesting a causal connection between the SMC loss and cardiovascular malfunction. However, the mechanisms of how progerin leads to massive SMC loss are unknown. In this study, using SMCs differentiated from HGPS induced pluripotent stem cells, we show that HGPS SMCs exhibit a profound proliferative defect, which is primarily caused by caspase-independent cell death. Importantly, progerin accumulation stimulates a powerful suppression of PARP1 and consequently triggers an activation of the error-prone nonhomologous end joining response. As a result, most HGPS SMCs exhibit prolonged mitosis and die of mitotic catastrophe. This study demonstrates a critical role of PARP1 in mediating SMC loss in patients with HGPS and elucidates a molecular pathway underlying the progressive SMC loss in progeria.
Subject(s)
Aging/physiology , Cell Death/physiology , Myocytes, Smooth Muscle/pathology , Poly(ADP-ribose) Polymerases/metabolism , Progeria/pathology , Cell Differentiation/physiology , Cell Survival/physiology , Down-Regulation/physiology , Fibroblasts/cytology , G2 Phase/physiology , Humans , Myocytes, Smooth Muscle/metabolism , Pluripotent Stem Cells/cytology , Poly (ADP-Ribose) Polymerase-1 , Primary Cell Culture , Progeria/metabolism , S Phase/physiology , Skin/cytologyABSTRACT
Hutchinson-Gilford progeria syndrome (HGPS) is a premature aging disease that is frequently caused by a de novo point mutation at position 1824 in LMNA. This mutation activates a cryptic splice donor site in exon 11, and leads to an in-frame deletion within the prelamin A mRNA and the production of a dominant-negative lamin A protein, known as progerin. Here we show that primary HGPS skin fibroblasts experience genome-wide correlated alterations in patterns of H3K27me3 deposition, DNA-lamin A/C associations, and, at late passages, genome-wide loss of spatial compartmentalization of active and inactive chromatin domains. We further demonstrate that the H3K27me3 changes associate with gene expression alterations in HGPS cells. Our results support a model that the accumulation of progerin in the nuclear lamina leads to altered H3K27me3 marks in heterochromatin, possibly through the down-regulation of EZH2, and disrupts heterochromatin-lamina interactions. These changes may result in transcriptional misregulation and eventually trigger the global loss of spatial chromatin compartmentalization in late passage HGPS fibroblasts.
Subject(s)
Genome, Human , Histones/metabolism , Lamins/metabolism , Progeria/genetics , Progeria/metabolism , Cell Line , Chromatin Immunoprecipitation , Fibroblasts/metabolism , Gene Expression Regulation , Heterochromatin/metabolism , Humans , Methylation , Protein Binding , Sequence Analysis, DNAABSTRACT
MicroRNAs (miRNAs) have gained much attention due to their critical roles in diverse biological events, including tumorigenesis. In this study, we demonstrate that miR-136 is down-regulated in two cohorts of patients with glioma. Furthermore, the low-level expression of miR-136 is significantly associated with a more aggressive and/or poor prognostic phenotype of patients with gliomas. Both gain- and loss-of-function experiments showed that miR-136 expression can reverse cisplatin resistance and enhance the response to cisplatin treatment. Furthermore, we identified a novel direct target of miR-136, the E2F transcription factor 1 (E2F1) oncogene. Depletion of E2F1 recapitulated the tumor-suppressive functions of miR-136, whereas re-expression of E2F1 attenuated the function of miR-136 in glioma cells. Finally, we revealed that miR-136 is inversely correlated with E2F1 expression in human glioma samples. The present study provides functional and mechanistic links between the tumor suppressor miR-136 and the oncogene E2F1 for the development of chemoresistance in human glioma. Our results indicate that targeting of the miR-136/E2F1 axis may provide a promising therapeutic approach to treat glioma.
Subject(s)
Brain Neoplasms/genetics , Cisplatin/pharmacology , Drug Resistance, Neoplasm/genetics , E2F1 Transcription Factor/metabolism , Glioma/genetics , MicroRNAs/genetics , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Blotting, Western , Brain Neoplasms/drug therapy , Brain Neoplasms/pathology , Cell Cycle/drug effects , Cell Movement/drug effects , Cell Proliferation/drug effects , E2F1 Transcription Factor/genetics , Female , Flow Cytometry , Follow-Up Studies , Gene Expression Regulation, Neoplastic/drug effects , Glioma/drug therapy , Glioma/pathology , Humans , Immunoenzyme Techniques , Male , Middle Aged , Neoplasm Recurrence, Local/drug therapy , Neoplasm Recurrence, Local/genetics , Neoplasm Recurrence, Local/pathology , Neoplasm Staging , Prognosis , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Survival Rate , Tumor Cells, CulturedABSTRACT
Cell heterogeneity and the inherent complexity due to the interplay of multiple molecular processes within the cell pose difficult challenges for current single-cell biology. We introduce an approach that identifies a disease phenotype from multiparameter single-cell measurements, which is based on the concept of "supercell statistics", a single-cell-based averaging procedure followed by a machine learning classification scheme. We are able to assess the optimal tradeoff between the number of single cells averaged and the number of measurements needed to capture phenotypic differences between healthy and diseased patients, as well as between different diseases that are difficult to diagnose otherwise. We apply our approach to two kinds of single-cell datasets, addressing the diagnosis of a premature aging disorder using images of cell nuclei, as well as the phenotypes of two non-infectious uveitides (the ocular manifestations of Behçet's disease and sarcoidosis) based on multicolor flow cytometry. In the former case, one nuclear shape measurement taken over a group of 30 cells is sufficient to classify samples as healthy or diseased, in agreement with usual laboratory practice. In the latter, our method is able to identify a minimal set of 5 markers that accurately predict Behçet's disease and sarcoidosis. This is the first time that a quantitative phenotypic distinction between these two diseases has been achieved. To obtain this clear phenotypic signature, about one hundred CD8(+) T cells need to be measured. Although the molecular markers identified have been reported to be important players in autoimmune disorders, this is the first report pointing out that CD8(+) T cells can be used to distinguish two systemic inflammatory diseases. Beyond these specific cases, the approach proposed here is applicable to datasets generated by other kinds of state-of-the-art and forthcoming single-cell technologies, such as multidimensional mass cytometry, single-cell gene expression, and single-cell full genome sequencing techniques.
Subject(s)
Diagnosis , Artificial Intelligence , HumansABSTRACT
Alzheimer's Disease (AD) is a leading cause of dementia characterized by amyloid plaques and neurofibrillary tangles, and its pathogenesis remains unclear. Current cellular models for AD often require several months to exhibit phenotypic features due to the lack of an aging environment in vitro. Lamin A is a key component of the nuclear lamina. Progerin, a truncated protein resulting from specific lamin A mutations, causes Hutchinson-Gilford Progeria Syndrome (HGPS), a disease that prematurely ages individuals. Studies have reported that lamin A expression is induced in the brains of AD patients, and overlapping cellular phenotypes have been observed between HGPS and AD cells. In this study, we investigated the effects of exogenous progerin expression on neural progenitor cells carrying familial AD mutations (FAD). Within three to four weeks of differentiation, these cells exhibited robust AD phenotypes, including increased tau phosphorylation, amyloid plaque accumulation, and an elevated Aß42 to Aß40 ratio. Additionally, progerin expression significantly increased AD cellular phenotypes such as cell death and cell cycle re-entry. Our results suggest that progerin expression could be used to create an accelerated model for AD development and drug screening.
Subject(s)
Alzheimer Disease , Progeria , Humans , Lamin Type A/genetics , Lamin Type A/metabolism , Alzheimer Disease/genetics , Alzheimer Disease/metabolism , Progeria/pathology , Aging/physiology , Cell Nucleus/metabolismABSTRACT
Introduction: Because of the problems of insufficient funds and traditional training methods in college sports agile training, an agile training system based on a wireless ad hoc network was developed to evaluate the effect of improving the sensitive quality of ordinary college students. Based on the ESP-MESH network, the lower computer realizes automatic networking between devices and tests the performance of the mesh network. Fourteen male college students received 9 weeks of agility training, with seven students in each of two groups: traditional agility training and agile equipment training. The researchers evaluated the performance of both groups in rapid disguise, body coordination, changing movements, and predictive decision-making. Results: There was no significant difference between the groups before training, but there were significant differences in the four abilities after training (p < 0.01). The experimental group had significant differences in rapid direction change and physical coordination (p < 0.05), and in changing movement and predictive decision-making ability (p < 0.01). Conclusion: Both traditional training and agile equipment training improve the agility quality of college students, and the latter shows better results in certain abilities. However, limited by other physical qualities, the improvement of motor changes and predictive decision-making ability is not as obvious as the other two abilities.
ABSTRACT
Hutchinson-Gilford Progeria Syndrome (HGPS) is a rare, fatal genetic disease that accelerates atherosclerosis. With a limited pool of HGPS patients, clinical trials face unique challenges and require reliable preclinical testing. We previously reported a 3D tissue engineered blood vessel (TEBV) microphysiological system fabricated with iPSC-derived vascular cells from HGPS patients. HGPS TEBVs exhibit features of HGPS atherosclerosis including loss of smooth muscle cells, reduced vasoactivity, excess extracellular matrix (ECM) deposition, inflammatory marker expression, and calcification. We tested the effects of HGPS therapeutics Lonafarnib and Everolimus separately and together, currently in Phase I/II clinical trial, on HGPS TEBVs. Everolimus decreased reactive oxygen species levels, increased proliferation, reduced DNA damage in HGPS vascular cells, and improved vasoconstriction in HGPS TEBVs. Lonafarnib improved shear stress response of HGPS iPSC-derived endothelial cells (viECs) and reduced ECM deposition, inflammation, and calcification in HGPS TEBVs. Combination treatment with Lonafarnib and Everolimus produced additional benefits such as improved endothelial and smooth muscle marker expression and reduced apoptosis, as well as increased TEBV vasoconstriction and vasodilation. These results suggest that a combined trial of both drugs may provide cardiovascular benefits beyond Lonafarnib, if the Everolimus dose can be tolerated.
Subject(s)
Atherosclerosis , Calcinosis , Induced Pluripotent Stem Cells , Progeria , Humans , Progeria/genetics , Everolimus/pharmacology , Everolimus/therapeutic use , Everolimus/metabolism , Endothelial Cells/metabolism , Induced Pluripotent Stem Cells/metabolism , Atherosclerosis/metabolism , Calcinosis/metabolism , Lamin Type A/geneticsABSTRACT
The activated form of Ran (Ran-GTP) stimulates spindle assembly in Xenopus laevis egg extracts, presumably by releasing spindle assembly factors, such as TPX2 (target protein for Xenopus kinesin-like protein 2) and NuMA (nuclear-mitotic apparatus protein) from the inhibitory binding of importin-alpha and -beta. We report here that Ran-GTP stimulates the interaction between TPX2 and the Xenopus Aurora A kinase, Eg2. This interaction causes TPX2 to stimulate both the phosphorylation and the kinase activity of Eg2 in a microtubule-dependent manner. We show that TPX2 and microtubules promote phosphorylation of Eg2 by preventing phosphatase I (PPI)-induced dephosphorylation. Activation of Eg2 by TPX2 and microtubules is inhibited by importin-alpha and -beta, although this inhibition is overcome by Ran-GTP both in the egg extracts and in vitro with purified proteins. As the phosphorylation of Eg2 stimulated by the Ran-GTP-TPX2 pathway is essential for spindle assembly, we hypothesize that the Ran-GTP gradient established by the condensed chromosomes is translated into the Aurora A kinase gradient on the microtubules to regulate spindle assembly and dynamics.
Subject(s)
Protein Kinases/metabolism , Signal Transduction , Spindle Apparatus/enzymology , ran GTP-Binding Protein/metabolism , Animals , Aurora Kinases , Cell Cycle Proteins , Protein Kinases/isolation & purification , Protein Serine-Threonine Kinases , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Xenopus Proteins , Xenopus laevis , ran GTP-Binding Protein/isolation & purificationABSTRACT
OBJECTIVE: Children with Hutchinson-Gilford progeria syndrome (HGPS) exhibit dramatically accelerated cardiovascular disease (CVD), causing death from myocardial infarction or stroke between the ages of 7 and 20 years. We undertook the first histological comparative evaluation between genetically confirmed HGPS and the CVD of aging. METHODS AND RESULTS: We present structural and immunohistological analysis of cardiovascular tissues from 2 children with HGPS who died of myocardial infarction. Both had features classically associated with the atherosclerosis of aging, as well as arteriolosclerosis of small vessels. In addition, vessels exhibited prominent adventitial fibrosis, a previously undescribed feature of HGPS. Importantly, although progerin was detected at higher rates in the HGPS coronary arteries, it was also present in non-HGPS individuals. Between the ages of 1 month and 97 years, progerin staining increased an average of 3.34% per year (P<0.0001) in coronary arteries. CONCLUSIONS: We find concordance among many aspects of cardiovascular pathology in both HGPS and geriatric patients. HGPS generates a more prominent adventitial fibrosis than typical CVD. Vascular progerin generation in young non-HGPS individuals, which significantly increases throughout life, strongly suggests that progerin has a role in cardiovascular aging of the general population.
Subject(s)
Atherosclerosis/pathology , Coronary Artery Disease/pathology , Progeria/pathology , Adolescent , Aging/pathology , Cardiovascular Diseases/pathology , Child , Female , Humans , Lamin Type A/analysis , Male , Myocardial Infarction/etiology , Progeria/complicationsABSTRACT
Hutchinson-Gilford progeria syndrome (HGPS) is the most dramatic form of human premature aging. Death occurs at a mean age of 13 years, usually from heart attack or stroke. Almost all cases of HGPS are caused by a de novo point mutation in the lamin A (LMNA) gene that results in production of a mutant lamin A protein termed progerin. This protein is permanently modified by a lipid farnesyl group, and acts as a dominant negative, disrupting nuclear structure. Treatment with farnesyltransferase inhibitors (FTIs) has been shown to prevent and even reverse this nuclear abnormality in cultured HGPS fibroblasts. We have previously created a mouse model of HGPS that shows progressive loss of vascular smooth muscle cells in the media of the large arteries, in a pattern that is strikingly similar to the cardiovascular disease seen in patients with HGPS. Here we show that the dose-dependent administration of the FTI tipifarnib (R115777, Zarnestra) to this HGPS mouse model can significantly prevent both the onset of the cardiovascular phenotype as well as the late progression of existing cardiovascular disease. These observations provide encouraging evidence for the current clinical trial of FTIs for this rare and devastating disease.
Subject(s)
Cardiovascular Diseases/prevention & control , Enzyme Inhibitors/pharmacology , Farnesyltranstransferase/antagonists & inhibitors , Progeria/complications , Animals , Cardiovascular Diseases/etiology , Disease Models, Animal , Disease Progression , Dose-Response Relationship, Drug , Enzyme Inhibitors/therapeutic use , Mice , Progeria/drug therapy , Quinolones/pharmacology , Quinolones/therapeutic useABSTRACT
Methylene blue (MB), as the first fully man-made medicine, has a wide range of clinical applications. Apart from its well-known applications in surgical staining, malaria, and methemoglobinemia, the anti-oxidative properties of MB recently brought new attention to this century-old drug. Mitochondrial dysfunction has been observed in systematic aging that affects many different tissues, including the brain and skin. This leads to increaseding oxidative stress and results in downstream phenotypes under age-related conditions. MB can bypass Complex I/III activity in mitochondria and diminish oxidative stress to some degree. This review summarizes the recent studies on the applications of MB in treating age-related conditions, including neurodegeneration, memory loss, skin aging, and a premature aging disease, progeria.
Subject(s)
Aging/drug effects , Methylene Blue/pharmacology , Animals , Brain/drug effects , Brain/pathology , Humans , Methylene Blue/chemistry , Models, Biological , Skin AgingABSTRACT
Methylene blue (MB) is a century-old medicine, a laboratory dye, and recently shown as a premier antioxidant that combats ROS-induced cellular aging in human skins. Given MB's molecular structure and light absorption properties, we hypothesize that MB has the potential to be considered as a sunscreen active for UV radiation protection. In this study, we tested the effects of MB on UVB ray-induced DNA double-strand breaks in primary human keratinocytes. We found that MB treatment reduced DNA damages caused by UVB irradiation and subsequent cell death. Next, we compared MB with Oxybenzone, which is the most commonly used chemical active ingredient in sunscreens but recently proven to be hazardous to aquatic ecosystems, in particular to coral reefs. At the same concentrations, MB showed more effective UVB absorption ability than Oxybenzone and significantly outperformed Oxybenzone in the prevention of UVB-induced DNA damage and the clearance of UVA-induced cellular ROS. Furthermore, unlike Oxybenzone, MB-containing seawater did not affect the growth of the coral species Xenia umbellata. Altogether, our study suggests that MB has the potential to be a coral reef-friendly sunscreen active ingredient that can provide broad-spectrum protection against UVA and UVB.
Subject(s)
Aging/drug effects , Anthozoa/drug effects , Methylene Blue/pharmacology , Skin/drug effects , Aging/pathology , Aging/radiation effects , Animals , Antioxidants/pharmacology , Benzophenones/adverse effects , Coral Reefs , DNA Breaks, Double-Stranded/drug effects , DNA Breaks, Double-Stranded/radiation effects , DNA Damage/drug effects , DNA Damage/radiation effects , Ecosystem , Humans , Keratinocytes/drug effects , Keratinocytes/radiation effects , Light/adverse effects , Methylene Blue/chemistry , Radiation Protection , Skin/radiation effects , Sunscreening Agents/adverse effects , Ultraviolet Rays/adverse effectsABSTRACT
OBJECTIVE: This study aimed to explore the effect of astaxanthin (ATX) on neuron damage, inflammatory factor expression and oxidative stress in mice with subarachnoid hemorrhage (SAH). METHODS: Specific-pathogen-free, 'Institute of Cancer Research', male mice were randomly divided into four groups: SAH group, sham group, SAH + placebo group (SAH + Vehicle group) and SAH + ATX group. Neurological function was scored in each group. Brain water content, reactive oxygen species (ROS) content and inflammatory factor levels in the brain were detected by wet-dry weighting method, DCFH-DA fluorescent probe staining method and ELISA, respectively. Expression of NADPH oxidase 2 (NOX2), glial fibrillary acidic protein (GFAP) and apoptosis-related proteins Bax and Bcl-2 were detected by Western blot and quantitative real-time polymerase chain reaction. Neuronal apoptosis was detected by TUNEL staining. RESULTS: Compared with sham group, neurological score, brain water content and ROS content in the other three groups increased significantly (all P<0.05). Neurological score, brain water content and ROS content in SAH + ATX group were lower than those in SAH group (all P<0.05). Compared with the sham group, there was increased expression of interleukin (IL)-6, IL-17 and tumor necrosis factor α (TNF-α), and increased neuronal apoptosis, as well as enhanced expression of NOX2, GFAP and Bax; while there was decreased IL-10 expression, and declined Bcl-2 expression, in the other three groups (all P<0.05). There was decreased expression of IL-6, IL-17 and TNF-α, declined expressions of NOX2, GFAP and Bax, and lowered neuronal apoptosis; while there was increased IL-10 expression, and enhanced Bcl-2 expression, in SAH + ATX group as compared to SAH group (all P<0.05). All indicators between SAH group and SAH + Vehicle group showed no significant differences (all P>0.05). CONCLUSION: Astaxanthin can decrease neuron damage, inhibit inflammatory response, and improve oxidative stress in SAH mice. Thus, astaxanthin is a method for treating SAH.
ABSTRACT
Hutchinson-Gilford progeria syndrome (HGPS) is a rare genetic disorder with features of accelerated aging. The majority of HGPS cases are caused by a de novo point mutation in the LMNA gene (c.1824C>T; p.G608G) resulting in progerin, a toxic lamin A protein variant. Children with HGPS typically die from coronary artery diseases or strokes at an average age of 14.6 years. Endothelial dysfunction is a known driver of cardiovascular pathogenesis; however, it is currently unknown how progerin antagonizes normal angiogenic function in HGPS. Here, we use human iPSC-derived endothelial cell (iPSC-EC) models to study angiogenesis in HGPS. We cultured normal and HGPS iPSC-ECs under both static and fluidic culture conditions. HGPS iPSC-ECs show reduced endothelial nitric oxide synthase (eNOS) expression and activity compared with normal controls and concomitant decreases in intracellular nitric oxide (NO) level, which result in deficits in capillary-like microvascular network formation. Furthermore, the expression of matrix metalloproteinase 9 (MMP-9) was reduced in HGPS iPSC-ECs, while the expression of tissue inhibitor metalloproteinases 1 and 2 (TIMP1 and TIMP2) was upregulated relative to healthy controls. Finally, we used an adenine base editor (ABE7.10max-VRQR) to correct the pathogenic c.1824C>T allele in HGPS iPSC-ECs. Remarkably, ABE7.10max-VRQR correction of the HGPS mutation significantly reduced progerin expression to a basal level, rescued nuclear blebbing, increased intracellular NO level, normalized the misregulated TIMPs, and restored angiogenic competence in HGPS iPSC-ECs. Together, these results provide molecular insights of endothelial dysfunction in HGPS and suggest that ABE could be a promising therapeutic approach for correcting HGPS-related cardiovascular phenotypes.
Subject(s)
Endothelial Cells/metabolism , Induced Pluripotent Stem Cells/metabolism , Progeria/genetics , Cellular Senescence , Down-Regulation , Humans , Progeria/pathologyABSTRACT
Huntington's disease (HD) is an autosomal neurodegenerative disorder caused by extended trinucleotide CAG repetition in the HTT gene. Wild-type huntingtin protein (HTT) is essential, involved in a variety of crucial cellular functions such as vesicle transportation, cell division, transcription regulation, autophagy, and tissue maintenance. The mutant HTT (mHTT) proteins in the body interfere with HTT's normal cellular functions and cause additional detrimental effects. In this review, we discuss multiple approaches targeting DNA and RNA to reduce mHTT expression. These approaches are categorized into non-allele-specific silencing and allele-specific-silencing using Single Nucleotide Polymorphisms (SNPs) and haplogroup analysis. Additionally, this review discusses a potential application of recent CRISPR prime editing technology in targeting HD.
Subject(s)
Huntington Disease , Alleles , Gene Expression Regulation , Gene Targeting , Humans , Huntingtin Protein/genetics , Huntingtin Protein/metabolism , Huntington Disease/genetics , Huntington Disease/therapyABSTRACT
Hutchinson-Gilford progeria syndrome (HGPS) is a rare accelerated aging disorder characterized by premature death from myocardial infarction or stroke. It is caused by de novo single-nucleotide mutations in the LMNA gene that activate a cryptic splice donor site, resulting in the production of a toxic form of lamin A, which is termed progerin. Here we present a potential genetic therapeutic strategy that utilizes antisense peptide-conjugated phosphorodiamidate morpholino oligomers (PPMOs) to block pathogenic splicing of mutant transcripts. Of several candidates, PPMO SRP-2001 provided the most significant decrease in progerin transcripts in patient fibroblasts. Intravenous delivery of SRP-2001 to a transgenic mouse model of HGPS produced significant reduction of progerin transcripts in the aorta, a particularly critical target tissue in HGPS. Long-term continuous treatment with SRP-2001 yielded a 61.6% increase in lifespan and rescue of vascular smooth muscle cell loss in large arteries. These results provide a rationale for proceeding to human trials.