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1.
Biomedicines ; 10(11)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36359301

RESUMO

The purposes of this study were to investigate the in vitro effects of arginine-glycine-aspertic acid (RGD) peptides derived from human dentin phosphophoryn (DPP) on human dental pulp stem cell-proliferation, differentiation and mineralization, and to explore the mechanism of the peptides' function. The 1 M concentration of soluble DPP-derived RGD peptides, RGD-1, RGD-2 and RGD-3 were coated onto non-tissue-culture polystyrene plates, and human dental pulp stem cells (hDPSCs) were cultured on them to examine the effects of the peptides on hDPSCs. In addition, 1 M arginine-alanine-aspertic acid (RAD) peptides were used as the control. Cell proliferation of hDPSCs was promoted by all three RGD peptides. All three RGD peptides had significantly higher alkaline phosphatase (ALP) activity compared to the control. RGD-3 induced the highest ALP activity compared to the control. RGD-3 also significantly promoted the mRNA expression of the following genes: 1.69-fold in dentine matrix protein-1 (DMP-1), 1.99-fold in dentine sialophosphoprotein (DSPP), 1.51-fold in ALP, and 2.31-fold in bone sialoprotein (BSP), as compared to the control group. Mineralization of hDPSCs was accelerated by all three RGD peptides, RGD-3 in particular. The MAPK p38 inhibitor SB202190 inhibited the effect of RGD-3 to a level comparable to the control, observed in both ALP activity assay and Arizarin red S (ARS) staining. It suggests that the p38 pathway may be responsible for eliciting the differentiation and mineralization effects of DPP-derived RGD peptides in the hDPSCs. The mRNA expression levels of the integrins ITGA1-5, ITGA7, ITGB1 and ITGB3 were significantly upregulated. Among them, expression of ITGA5 was promoted 1.9-fold, ITGA7 1.58-fold, ITGB1 1.75-fold and ITGB3 1.9-fold compared to the control. It suggests the possible involvement of these integrin channels in different subunit combinations facilitating signal transduction for differentiation of hDPSCs into odontoblasts. As conclusions, human DPP-derived RGD peptides RGD-1, RGD-2 and RGD-3 promoted the proliferation, differentiation and mineralization of hDPSCs in vitro. Among the three peptides, RGD-3 had the most significant effects. It is also suggested that RGD-3 binds to integrin receptors on the surface of hDPSCs and regulates the odontogenic gene expression and differentiation via activation of p38 of MAPK pathway. DPP-derived RGD-3 may be a promising choice in the formulation of a novel material for vital pulp therapy to induce dental pulp stem cells into odontoblasts and form reparative dentin on the exposed pulp tissue.

2.
Adv Sci (Weinh) ; : e2203541, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36382556

RESUMO

K2 NiF4 -type Ba-Li oxyhydride (BLHO) transitions to a so-called hydride superionic conductor, exhibiting a high and essentially temperature-independent hydride ion (H- ) conductivity over 0.01 S cm-1 through the disordering of H- vacancies above 300 °C. In this study, a Ba-Li-Na-H-O oxyhydride system synthesized in which lithium is partially substituted with sodium in BLHO and investigated the effects of Na content on the phase transition behavior and the conductivity. Structural refinements and differential scanning calorimetry experiments confirmed a lowering trend in the phase transition temperatures and decreasing enthalpy changes for the transition with increasing Na content. Substitution of not <40% of Li with Na lowered the degree of ordered vacancies at the H- sites at room temperature and improved conductivities by more than two orders of magnitude in the low-temperature region (T < 300 °C) before the phase transition. These findings clearly show that introducing Na into the lattice effectively stabilizes the high-conductive phase of BLHO.

3.
J Funct Biomater ; 13(4)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36412887

RESUMO

Several desensitizers routinely used clinically for dentin hypersensitivity are expected to inhibit demineralization. This study aimed to evaluate the effectiveness of sealing materials in inhibiting demineralization and increasing fluorine (F) uptake by acid-treated root surfaces. Five noncarious extracted human teeth were used to produce specimens. Three different fluoride-containing materials, namely "MS Coat F" (MS), "MS Coat Hys Block Gel" (HS), and CTX2 Varnish (FV), were used herein. Each material was applied to the demineralized root surface. Single sections were obtained from each specimen. All surfaces of each specimen, except the polished surface, were covered with wax and immersed in an automatic pH cycling system for 2 weeks. Fluorine and calcium distributions in the carious lesions of each specimen were evaluated using proton-induced gamma emission (PIGE) and X-ray (PIXE) techniques, respectively. Dentin demineralization was analyzed using transverse microradiography (TMR) before and after pH cycling. µPIXE/PIGE analysis demonstrated that all sample groups showed increased fluoride uptake on the root surface. TMR analysis revealed that both HS and FV showed significantly lower integrated mineral loss values than the control group. All three samples demonstrated a tendency towards increased fluoride uptake from fluoride-containing hypersensitivity desensitizers and a demineralization inhibition effect on root dentin.

4.
Mol Med ; 28(1): 143, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36447136

RESUMO

BACKGROUND: Mesenchymal stem cells (MSCs) are multipotent stromal cells and could exert hepatoprotective effects against acute liver injury, steatohepatitis, and fibrogenesis. Here, we evaluated the effects of human adipose derived stem cells (hADSCs) to attenuate experimentally induced hepatic fibrosis and early cirrhosis in rats. METHODS: Hepatic fibrosis was induced by intraperitoneal injections of CCl4 (0.1 ml/100 g body weight) twice a week for 8 weeks. hADSCs were isolated and cultured on polyethylene discs coated with hydroxyapatite and 2 cm diameter disc was surgically implanted on the right lateral lobe of the liver. Discs implanted without hADSCs served as control. The animals were injected again with CCl4 once a week for another 8 weeks. All the animals were sacrificed at the end of 16th week. RESULTS: Serial administrations of CCl4 resulted in well developed fibrosis and early cirrhosis at 8th week which maintained until the 16th week. Animals treated with hADSC discs depicted over 50% decrease of collagen with significant increase in serum albumin and total protein levels. Immunohistochemical staining for TGF-ß1, α-smooth muscle actin, and collagen type I and type III demonstrated marked decrease compared to the animals without hADSC treatment. CONCLUSIONS: Treatment with hADSCs improved liver functions, markedly reduced hepatic fibrosis and early cirrhosis. Various pleiotropic and paracrine factors secreted from the hADSCs seem to serve as reparative functions in the attenuation of liver cirrhosis. The data demonstrated that treatment with hADSCs can be successfully used as a potent therapeutic method to prevent progression of hepatic fibrosis and related adverse events.

5.
J Oral Biosci ; 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36336319

RESUMO

OBJECTIVES: Bone, platelet concentrate, and tooth-derived dentin/cementum have been used as autologous materials in regenerative medicine Dentin materials were first recycled in 2002 for bone regeneration in humans, although bone autografts were noted in the 19th century, and auto-platelet concentrates were developed in 1998. Dentin/cementum-based material therapy has been applied as an innovative technique for minimally invasive bone surgery, while bone autografts are associated with donor site morbidity. METHODS: In October 2021, PubMed, Google Scholar, Scopus, and the Cochrane Library databases from 1980 to 2020 were screened. RESULTS: The demineralized dentin/cementum matrix (DDM) had better performance in bone induction and bone regeneration than mineralized dentin. CONCLUSIONS: Unlike cell culture therapy, DDM is a matrix-based therapy that includes growth factors. A matrix-based system is a realistic and acceptable treatment, even in developing countries. The aim of this review was to summarize the evidence related to both animal studies and human clinical cases using human dentin materials with a patch of cementum, especially DDM.

6.
Arthritis Res Ther ; 24(1): 228, 2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36207753

RESUMO

BACKGROUND: Adipose-derived mesenchymal stem cells (ASCs) have gained attention as a new treatment for systemic sclerosis (SSc). Low-molecular-weight heparin (LMWH) enhances cell function and stimulates the production of hepatocyte growth factor (HGF) in a variety of cells. This study investigated the effects of LMWH on the functions of mouse ASCs (mASCs), and the therapeutic effects of mASCs activated with LMWH (hep-mASCs) in mouse models of SSc. METHODS: The cellular functions of mASCs cultured with different concentrations of LMWH were determined. Mice were divided into four groups: bleomycin (BLM)-induced SSc (BLM-alone), BLM-induced SSc administered with mASCs (BLM-mASC), and BLM-induced SSc administered with mASCs activated with 10 or 100 µg/mL LMWH (BLM-hep-mASC); there were 9 mice per group (n = 9). Skin inflammation and fibrosis were evaluated using histological and biochemical examinations and gene expression levels. RESULTS: In vitro assays showed that migration ability and HGF production were significantly higher in hep-mASCs than in mASCs alone. The mRNA expression levels of cell migration factors were significantly upregulated in hep-mASCs compared to those in mASCs alone. The hep-mASCs accumulated in the skin tissues more than mASCs alone. The thickness of skin and hydroxyproline content in BLM-hep-mASC groups were significantly decreased, and the skin mRNA expression levels of interleukin-2, α-smooth muscle actin, transforming growth factor ß1, collagen type 1 alpha 1, and tissue inhibitor of metalloproteinase 2 were significantly downregulated compared to those in the BLM-alone group. CONCLUSIONS: hep-mASCs showed higher anti-inflammatory and anti-fibrotic effects than mASCs alone and may be a promising candidate for SSc treatment.


Assuntos
Células-Tronco Mesenquimais , Fibrose Pulmonar , Escleroderma Sistêmico , Actinas/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Bleomicina/análogos & derivados , Bleomicina/toxicidade , Colágeno/metabolismo , Modelos Animais de Doenças , Fibrose , Heparina de Baixo Peso Molecular/metabolismo , Fator de Crescimento de Hepatócito/genética , Fator de Crescimento de Hepatócito/metabolismo , Hidroxiprolina/metabolismo , Interleucina-2/metabolismo , Pulmão/patologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Compostos Organometálicos , Fibrose Pulmonar/metabolismo , RNA Mensageiro/metabolismo , Escleroderma Sistêmico/induzido quimicamente , Escleroderma Sistêmico/tratamento farmacológico , Escleroderma Sistêmico/metabolismo , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Inibidor Tecidual de Metaloproteinase-2/farmacologia , Fator de Crescimento Transformador beta1/metabolismo
7.
Respir Med Res ; 82: 100965, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36283327

RESUMO

BACKGROUND: Sarcopenia, defined using abdominal computed tomography (CT), has been used as a prognostic marker for patients with idiopathic pulmonary fibrosis (IPF). However, no consensus on the impact of sarcopenia as defined using chest CT exists. Therefore, this study aimed to investigate the impact of sarcopenia, defined using CT at the carina-level, on the long-term prognosis of patients with IPF. METHODS: This single-center retrospective cohort study included 117 patients with IPF. Sarcopenia was defined as skeletal muscle mass measured at the carina-level on chest CT images. All-cause mortality was analyzed using the Kaplan-Meier method, and the log-rank test was used to evaluate the differences between sarcopenia and non-sarcopenia groups. A Cox proportional hazards regression model was used to analyze the impact of sarcopenia on all-cause mortality in model 1 with adjustment for body mass index and gender-age-physiology stage as a confounding factor and in model 2 with sex, age, and% forced vital capacity (FVC). RESULTS: The median follow-up period was 956 days, and 57 deaths were recorded. The sarcopenia group had a significantly lower survival rate than the non-sarcopenia group. The multivariate Cox proportional hazards analysis revealed that sarcopenia was a significant predictor of all-cause mortality in models 1 and 2. In patients with no diffusing capacity for carbon monoxide (DLCO) measurement, sarcopenia was a significant prognostic predictor of all-cause mortality independent of%FVC. CONCLUSION: Sarcopenia, defined at the carina level, is a risk factor for all-cause mortality in patients with IPF. Assessment of sarcopenia by CT imaging is useful and less burdensome in patients with IPF.

8.
Genet Med ; 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36305856

RESUMO

PURPOSE: Cerebellar hypoplasia and atrophy (CBHA) in children is an extremely heterogeneous group of disorders, but few comprehensive genetic studies have been reported. Comprehensive genetic analysis of CBHA patients may help differentiating atrophy and hypoplasia and potentially improve their prognostic aspects. METHODS: Patients with CBHA in 176 families were genetically examined using exome sequencing. Patients with disease-causing variants were clinically evaluated. RESULTS: Disease-causing variants were identified in 96 of the 176 families (54.5%). After excluding 6 families, 48 patients from 42 families were categorized as having syndromic associations with CBHA, whereas the remaining 51 patients from 48 families had isolated CBHA. In 51 patients, 26 aberrant genes were identified, of which, 20 (76.9%) caused disease in 1 family each. The most prevalent genes were CACNA1A, ITPR1, and KIF1A. Of the 26 aberrant genes, 21 and 1 were functionally annotated to atrophy and hypoplasia, respectively. CBHA+S was more clinically severe than CBHA-S. Notably, ARG1 and FOLR1 variants were identified in 2 families, leading to medical treatments. CONCLUSION: A wide genetic and clinical diversity of CBHA was revealed through exome sequencing in this cohort, which highlights the importance of comprehensive genetic analyses. Furthermore, molecular-based treatment was available for 2 families.

9.
Radiat Prot Dosimetry ; 198(13-15): 964-970, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36083754

RESUMO

A tractor-based robot with the capability of real-time assessing and visualizing the radioactive material density and fertility distribution of farmlands has been developed to accelerate the recovery process of the farmlands suffered by the accident of the Fukushima Daiichi Nuclear Power Plant (FDNPP). In a field test at a decontaminated farmland near FDNPP, within-field heterogeneities of soil contamination and fertility are clarified almost in real-time. Results obtained by this robot are consistent with the map by the conventional soil sampling or the history of decontamination activities.


Assuntos
Acidente Nuclear de Fukushima , Monitoramento de Radiação , Robótica , Poluentes Radioativos do Solo , Radioisótopos de Césio/análise , Fazendas , Fertilidade , Japão , Centrais Nucleares , Monitoramento de Radiação/métodos , Solo , Poluentes Radioativos do Solo/análise
10.
ACS Appl Mater Interfaces ; 14(36): 40599-40611, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36052562

RESUMO

Amyloidosis pathologically proceeds via production of amyloidogenic proteins by organs, formation of protein aggregates through structural changes, and their deposition on tissues. A growing body of evidence demonstrates that amyloidosis generally develops through three critical pathological steps: (1) production of amyloid precursor proteins, (2) amyloid formation, and (3) amyloid deposition. However, no clinically effective therapy that is capable of targeting each pathological step of amyloidosis independently is currently available. Here, we combined therapeutic effects and developed a short hairpin RNA expression vector (shRNA) complex with a cyclodextrin-appended cationic dendrimer (CDE) as a novel multitarget therapeutic drug that is capable of simultaneously suppressing these three steps. We evaluated its therapeutic effects on systemic transthyretin (ATTR) amyloidosis and Alzheimer's disease (AD) as localized amyloidosis, by targeting TTR and amyloid ß, respectively. CDE/shRNA exhibited RNAi effects to suppress amyloid protein production and also achieved both inhibition of amyloid formation and disruption of existing amyloid fibrils. The multitarget therapeutic effects of CDE/shRNA were confirmed by evaluating TTR deposition reduction in early- and late-onset human ATTR amyloidosis model rats and amyloid ß deposition reduction in AppNL-G-F/NL-G-F AD model mice. Thus, the CDE/shRNA complex exhibits multifunctional therapeutic efficacy and may reveal novel strategies for establishing curative treatments for both systemic and localized amyloidosis.


Assuntos
Doença de Alzheimer , Amiloidose , Ciclodextrinas , Dendrímeros , Doença de Alzheimer/tratamento farmacológico , Amiloide , Peptídeos beta-Amiloides , Proteínas Amiloidogênicas , Amiloidose/tratamento farmacológico , Amiloidose/metabolismo , Animais , Ciclodextrinas/farmacologia , Dendrímeros/farmacologia , Humanos , Camundongos , RNA Interferente Pequeno , Ratos
11.
Transl Neurodegener ; 11(1): 41, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-36109806

RESUMO

BACKGROUND: Aberrant DNA methylation patterns have been observed in neurodegenerative diseases, including Alzheimer's disease (AD), and dynamic changes in DNA methylation are closely associated with the onset and progression of these diseases. Particularly, hypomethylation of the amyloid precursor protein gene (APP) has been reported in patients with AD. METHODS: In this study, we used catalytically inactivated Cas9 (dCas9) fused with Dnmt3a for targeted DNA methylation of APP, and showed that the CRISPR/dCas9-Dnmt3a-mediated DNA methylation system could efficiently induce targeted DNA methylation of APP both in vivo and in vitro. RESULTS: We hypothesized that the targeted methylation of the APP promoter might rescue AD-related neuronal cell death by reducing APP mRNA expression. The cultured APP-KI mouse primary neurons exhibited an altered DNA-methylation pattern on the APP promoter after dCas9-Dnmt3a treatment. Likewise, the APP mRNA level was significantly reduced in the dCas9-Dnmt3a-treated wild-type and APP-KI mouse primary neurons. We also observed decreased amyloid-beta (Aß) peptide level and Aß42/40 ratio in the dCas9-Dnmt3a-treated APP-KI mouse neurons compared to the control APP-KI mouse neurons. In addition, neuronal cell death was significantly decreased in the dCas9-Dnmt3a-treated APP-KI mouse neurons. Furthermore, the in vivo methylation of APP in the brain via dCas9-Dnmt3a treatment altered Aß plaques and attenuated cognitive and behavioral impairments in the APP-KI mouse model. CONCLUSIONS: These results suggest that the targeted methylation of APP via dCas9-Dnmt3a treatment can be a potential therapeutic strategy for AD.


Assuntos
Doença de Alzheimer , Metilação de DNA , Doença de Alzheimer/genética , Doença de Alzheimer/terapia , Peptídeos beta-Amiloides , Precursor de Proteína beta-Amiloide/genética , Animais , Encéfalo , DNA , Metilases de Modificação do DNA/genética , Modelos Animais de Doenças , Camundongos , Placa Amiloide/genética , RNA Mensageiro
12.
Proc Natl Acad Sci U S A ; 119(40): e2204828119, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36161942

RESUMO

Biased G protein-coupled receptor (GPCR) ligands, which preferentially activate G protein or ß-arrestin signaling pathways, are leading to the development of drugs with superior efficacy and reduced side effects in heart disease, pain management, and neuropsychiatric disorders. Although GPCRs are implicated in the pathophysiology of Alzheimer's disease (AD), biased GPCR signaling is a largely unexplored area of investigation in AD. Our previous work demonstrated that GPR3-mediated ß-arrestin signaling modulates amyloid-ß (Aß) generation in vitro and that Gpr3 deficiency ameliorates Aß pathology in vivo. However, Gpr3-deficient mice display several adverse phenotypes, including elevated anxiety-like behavior, reduced fertility, and memory impairment, which are potentially associated with impaired G protein signaling. Here, we generated a G protein-biased GPR3 mouse model to investigate the physiological and pathophysiological consequences of selective elimination of GPR3-mediated ß-arrestin signaling in vivo. In contrast to Gpr3-deficient mice, G protein-biased GPR3 mice do not display elevated anxiety levels, reduced fertility, or cognitive impairment. We further determined that G protein-biased signaling reduces soluble Aß levels and leads to a decrease in the area and compaction of amyloid plaques in the preclinical AppNL-G-F AD mouse model. The changes in amyloid pathology are accompanied by robust microglial and astrocytic hypertrophy, which suggest a protective glial response that may limit amyloid plaque development in G protein-biased GPR3 AD mice. Collectively, these studies indicate that GPR3-mediated G protein and ß-arrestin signaling produce discrete and separable effects and provide proof of concept for the development of safer GPCR-targeting therapeutics with more directed pharmacological action for AD.


Assuntos
Doença de Alzheimer , Amiloidose , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Modelos Animais de Doenças , Proteínas de Ligação ao GTP/metabolismo , Camundongos , Camundongos Transgênicos , Placa Amiloide/patologia , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , beta-Arrestinas/metabolismo
13.
Biochem Biophys Res Commun ; 629: 135-141, 2022 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-36116376

RESUMO

Interstitial lung disease (ILD) is a life-threatening pathological condition that causes respiratory failure and often presents as pulmonary fibrosis. Although it is treated using immunosuppressive and antifibrotic agents, the beneficial effects of these agents remain limited. Thus, the development of new therapeutic strategies for lung fibrosis is crucial. Mesenchymal stem/stromal cells (MSCs) have multilineage differentiation potential; additionally, they have anti-inflammatory and antifibrotic effects as well as the ability to modulate the immune response and modify the microenvironment at the site of engraftment. Numerous adipose-derived MSCs (ASCs) are present in the adipose tissue. Heparin and low-molecular-weight heparin (LMWH) mediate the secretion of several cytokines and growth factors with cell migratory and antifibrotic effects. This study aimed to confirm the therapeutic effect of LMWH-activated ASCs on ILD. Mouse ASCs (mASCs) were cultured in an LMWH-supplemented medium. LMWH significantly increased the number of mASC and enhanced their migratory, anti-inflammatory, and antifibrotic effects. Furthermore, mice with bleomycin-induced pulmonary fibrosis were intravenously administered LMWH-activated mASCs. The relative mRNA expression of inflammation-related genes in ILD lungs was significantly lower in the treatment group than in the pathological model group. Our findings suggest that LMWH-activated mASC administration reduces lung fibrosis.


Assuntos
Transplante de Células-Tronco Mesenquimais , Fibrose Pulmonar , Tecido Adiposo , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Bleomicina/efeitos adversos , Citocinas , Heparina , Heparina de Baixo Peso Molecular/efeitos adversos , Camundongos , Camundongos Endogâmicos C57BL , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/tratamento farmacológico , RNA Mensageiro , Células Estromais
14.
Polymers (Basel) ; 14(16)2022 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-36015671

RESUMO

The present study was to investigate the rheological property, printability, and cell viability of alginate-gelatin composed hydrogels as a potential cell-laden bioink for three-dimensional (3D) bioprinting applications. The 2 g of sodium alginate dissolved in 50 mL of phosphate buffered saline solution was mixed with different concentrations (1% (0.5 g), 2% (1 g), 3% (1.5 g), and 4% (2 g)) of gelatin, denoted as GBH-1, GBH-2, GBH-3, and GBH-4, respectively. The properties of the investigated hydrogels were characterized by contact angle goniometer, rheometer, and bioprinter. In addition, the hydrogel with a proper concentration was adopted as a cell-laden bioink to conduct cell viability testing (before and after bioprinting) using Live/Dead assay and immunofluorescence staining with a human corneal fibroblast cell line. The analytical results indicated that the GBH-2 hydrogel exhibited the lowest loss rate of contact angle (28%) and similar rheological performance as compared with other investigated hydrogels and the control group. Printability results also showed that the average wire diameter of the GBH-2 bioink (0.84 ± 0.02 mm (*** p < 0.001)) post-printing was similar to that of the control group (0.79 ± 0.05 mm). Moreover, a cell scaffold could be fabricated from the GBH-2 bioink and retained its shape integrity for 24 h post-printing. For bioprinting evaluation, it demonstrated that the GBH-2 bioink possessed well viability (>70%) of the human corneal fibroblast cell after seven days of printing under an ideal printing parameter combination (0.4 mm of inner diameter needle, 0.8 bar of printing pressure, and 25 °C of printing temperature). Therefore, the present study suggests that the GBH-2 hydrogel could be developed as a potential cell-laden bioink to print a cell scaffold with biocompatibility and structural integrity for soft tissues such as skin, cornea, nerve, and blood vessel regeneration applications.

15.
Front Aging Neurosci ; 14: 909586, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35936777

RESUMO

All clinical BACE1-inhibitor trials for the treatment of Alzheimer's Disease (AD) have failed due to insufficient efficacy or side effects like worsening of cognitive symptoms. However, the scientific evidence to date suggests that BACE1-inhibition could be an effective preventative measure if applied prior to the accumulation of amyloid-beta (Aß)-peptide and resultant impairment of synaptic function. Preclinical studies have associated BACE1-inhibition-induced cognitive deficits with decreased dendritic spine density. Therefore, we investigated dose-dependent effects of BACE1-inhibition on hippocampal dendritic spine dynamics in an APP knock-in mouse line for the first time. We conducted in vivo two-photon microscopy in the stratum oriens layer of hippocampal CA1 neurons in 3.5-month-old App NL-G-F GFP-M mice over 6 weeks to monitor the effect of potential preventive treatment with a high and low dose of the BACE1-inhibitor NB-360 on dendritic spine dynamics. Structural spine plasticity was severely impaired in untreated App NL-G-F GFP-M mice, although spines were not yet showing signs of degeneration. Prolonged high-dose BACE1-inhibition significantly enhanced spine formation, improving spine dynamics in the AD mouse model. We conclude that in an early AD stage characterized by low Aß-accumulation and no irreversible spine loss, BACE1-inhibition could hold the progressive synapse loss and cognitive decline by improving structural spine dynamics.

16.
Front Mol Neurosci ; 15: 909989, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35966019

RESUMO

Mitochondria play a crucial role in Alzheimer's disease (AD) onset and progression. Traditional transgenic AD mouse models which were widely used in the past decades share a common limitation: The overexpression of APP and overproduction of amyloid-beta (Aß) are accompanied by other APP peptide fragments, which could introduce artificial and non-clinically relevant phenotypes. Here, we performed an in-depth and time-resolved behavioral and metabolic characterization of a clinically relevant AD mouse model engineered to express normal physiological levels of APP harboring humanized Swedish (K670N/M671L), Beyreuther/Iberian (I716F), and Arctic (E693G) mutations (App NL-G-F/NL-G-F ), termed APP knock-in (APPKI) mice. Our result showed that APPKI mice exhibited fear learning deficits at 6-m age and contextual memory deficit at 12-m age. Histopathological analysis revealed mild amyloidosis (6E10) accompanied by microgliosis (Iba1) as early as 3 months, which progressed significantly together with significant astrocytosis at 6 and 12 m. We further analyzed hippocampal mitochondrial dysfunction by multiple assays, while 3-m APPKI mice brain mitochondrial function remains a similar level as WT mice. Significant mitochondrial dysfunction characterized by decreased ATP production and higher membrane potential with subsequent overproduction of reactive oxygen species (ROS) was observed in mitochondria isolated from 7-m APPKI mice hippocampal tissue. Morphologically, these mitochondria were larger in volume with a decreased level of mitochondrial fusion protein mitofusin-2 (MFN2). At 12 months, APPKI mice exhibit a significantly decreased total mitochondrial oxygen consumption rate (OCR) in isolated hippocampal mitochondria detected by high-resolution respirometry. These data indicate early mitochondrial dysfunction in the brain at pre-symptomatic age in the App NL-G-F/NL-G-mice, which may play a key role in the progression of the disease. Moreover, the identified behavioral and bioenergetic alterations in this clinically relevant AD mouse model provide a valuable tool to optimize the temporal component for therapeutic interventions to treat AD.

18.
Front Oncol ; 12: 863260, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35978807

RESUMO

Light flash and odor during radiation therapy are well-known phenomena, but the details are poorly understood, particularly in pediatric patients. Therefore, we conducted a prospective observational study of these events in pediatric patients (age ≤20 years old) who received radiotherapy at our center from January 2019 to November 2021. Light flash and odor were evaluated using a patient-reported checklist including the presence, strength, and duration of the phenomenon, and color of light or type of odor. 53 patients who received proton therapy (n=47) and photon radiotherapy (n=6) were enrolled in this study. The median age of the patients was 10, ranged from 5 to 20. The patients who was able to see the light flash was 4, and all of them received retina irradiation. This was equivalent to 57% of the patients who received radiotherapy to retina (n=7). The light was bright and colored mainly blue and purple, which seemed to be consistent with Cherenkov light. Odor was sensed by 9 (17%) patients, and seven patients of the 9 received nasal cavity irradiation. This was equivalent to 41% of the patients who received nasal cavity irradiation (n=17). Other 2 patients received proton therapy to brain tumor. The odors were mainly described as plastic, burnt and disinfectant, which may be caused by ozone generated during irradiation. These data suggest that pediatric patients with retinal and nasal cavity irradiation frequently sense light flashes or odor. So adequate care is necessary so that these patients are not worried about this phenomenon.

19.
Metabolites ; 12(7)2022 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-35888718

RESUMO

Iron is an essential nutrient in the body. However, iron generates oxidative stress and hence needs to be bound to carrier proteins such as the glycoprotein transferrin (Tf) in body fluids. We previously reported that cerebrospinal fluid contains Tf glycan-isoforms that are derived from the brain, but their origins at the cellular level in the brain have not yet been elucidated. In the present report, we described the localization of Tf protein and mRNA in mouse and human brain tissue. In situ hybridization of mouse brain tissue revealed that Tf mRNA is expressed by different cell types such as epithelial cells in the choroid plexus, oligodendrocyte-like cells in the medulla, and neurons in the cortex, hippocampus, and basal ganglia. In contrast, Tf protein was barely detected by immunohistochemistry in hippocampal and some cortical neurons, but it was detected in other types of cells such as oligodendrocyte-like cells and choroid plexus epithelial cells. The results showed that Tf mRNA is expressed by neural cells, while Tf protein is expressed in different brain regions, though at very low levels in hippocampal neurons. Low Tf level in the hippocampus may increases susceptibility to iron-induced oxidative stress, and account for neuron death in neurodegenerative diseases.

20.
Acta Neuropathol Commun ; 10(1): 99, 2022 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-35794654

RESUMO

Complement is involved in developmental synaptic pruning and pathological synapse loss in Alzheimer's disease. It is posited that C1 binding initiates complement activation on synapses; C3 fragments then tag them for microglial phagocytosis. However, the precise mechanisms of complement-mediated synaptic loss remain unclear, and the role of the lytic membrane attack complex (MAC) is unexplored. We here address several knowledge gaps: (i) is complement activated through to MAC at the synapse? (ii) does MAC contribute to synaptic loss? (iii) can MAC inhibition prevent synaptic loss? Novel methods were developed and optimised to quantify C1q, C3 fragments and MAC in total and regional brain homogenates and synaptoneurosomes from WT and AppNL-G-F Alzheimer's disease model mouse brains at 3, 6, 9 and 12 months of age. The impact on synapse loss of systemic treatment with a MAC blocking antibody and gene knockout of a MAC component was assessed in Alzheimer's disease model mice. A significant increase in C1q, C3 fragments and MAC was observed in AppNL-G-F mice compared to controls, increasing with age and severity. Administration of anti-C7 antibody to AppNL-G-F mice modulated synapse loss, reflected by the density of dendritic spines in the vicinity of plaques. Constitutive knockout of C6 significantly reduced synapse loss in 3xTg-AD mice. We demonstrate that complement dysregulation occurs in Alzheimer's disease mice involving the activation (C1q; C3b/iC3b) and terminal (MAC) pathways in brain areas associated with pathology. Inhibition or ablation of MAC formation reduced synapse loss in two Alzheimer's disease mouse models, demonstrating that MAC formation is a driver of synapse loss. We suggest that MAC directly damages synapses, analogous to neuromuscular junction destruction in myasthenia gravis.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/patologia , Animais , Ativação do Complemento , Complemento C1q/genética , Complemento C1q/metabolismo , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Proteínas do Sistema Complemento/metabolismo , Camundongos , Placa Amiloide/patologia , Sinapses/patologia
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