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1.
Mater Today Bio ; 26: 101038, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38638704

RESUMO

The ideal implant surface plays a substantial role in maintaining bone homeostasis by simultaneously promoting osteoblast differentiation and limiting overactive osteoclast activity to a certain extent, which leads to satisfactory dynamic osseointegration. However, the rational search for implant materials with an ideal surface structure is challenging and a hot research topic in the field of tissue engineering. In this study, we constructed titanium dioxide titanium nanotubes (TNTs) by anodic oxidation and found that this structure significantly promoted osteoblast differentiation and inhibited osteoclast formation and function while simultaneously inhibiting the total protein levels of proline-rich tyrosine kinase 2 (PYK2) and focal adhesion kinase (FAK). Knockdown of the PYK2 gene by siRNA significantly suppressed the number and osteoclastic differentiation activity of mouse bone marrow mononuclear cells (BMMs), while overexpression of PYK2 inhibited osteogenesis and increased osteoclastic activity. Surprisingly, we found for the first time that neither knockdown nor overexpression of the FAK gene alone caused changes in osteogenesis or osteoclastic function. More importantly, compared with deletion or overexpression of PYK2/FAK alone, coexpression or cosilencing of the two kinases accelerated the effects of TNTs on osteoclastic and osteogenic differentiation on the surface of cells. Furthermore, in vivo experiments revealed a significant increase in positiveexpression-PYK2 cells on the surface of TNTs, but no significant change in positiveexpression -FAK cells was observed. In summary, PYK2 is a key effector molecule by which osteoblasts sense nanotopological mechanical signals and maintain bone homeostasis around implants. These results provide a referable molecular mechanism for the future development and design of homeostasis-based regulatory implant biomaterials.

3.
United European Gastroenterol J ; 12(3): 390-398, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38159037

RESUMO

BACKGROUND AND AIMS: Duodenal perforation caused by foreign bodies (FBs) is very rare but is an urgent emergency that traditionally requires surgical intervention. Several case reports have reported the successful endoscopic removal of duodenal perforating FBs. Here we aimed to evaluate the safety and efficacy of endoscopic management of duodenal perforating FBs in adults. METHODS: Between October 2004 and October 2022, 12,851 patients with endoscopically diagnosed gastrointestinal FBs from four tertiary hospitals in China were retrospectively reviewed. Patients were enrolled if they were endoscopically and/or radiographically diagnosed with duodenal perforating FBs. RESULTS: The incidence of duodenal total FBs and perforating FBs was 1.9% and 0.3%, respectively. Thirty-four patients were enrolled. Endoscopic removal was achieved in 25 patients (73.5%), and nine patients (26.5%) received surgery. For the endoscopic group, most perforating FBs were located in the duodenal bulb (36.0%) and descending part (28.0%). The adverse events included 3 mucosal injuries and 1 localized peritonitis. All patients were cured after conventional treatment. In the surgical group, most FBs were lodged in the descending part (55.6%). One patient developed localized peritonitis and one patient died of multiple organ failure. The significant features of FBs requiring surgery included FB over 10 cm, both sides perforation, multiple perforating FBs and massive pus overflow. CONCLUSION: Endoscopic removal of duodenal perforating FBs is safe and effective, and can be the first choice of treatment for experienced endoscopists. Surgical intervention may be required for patients with FBs over 10 cm, both sides perforation, multiple perforating FBs, or severe infections.


Assuntos
Corpos Estranhos , Peritonite , Adulto , Humanos , Estudos Retrospectivos , Endoscopia , Duodeno/diagnóstico por imagem , Duodeno/cirurgia , Corpos Estranhos/complicações , Corpos Estranhos/cirurgia
4.
Orthop Surg ; 15(12): 3026-3045, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37942509

RESUMO

Cartilage regeneration remains difficult due to a lack of blood vessels. Degradation of the extracellular matrix (ECM) causes cartilage defects, and the ECM provides the natural environment and nutrition for cartilage regeneration. Until now, collagen hydrogels are considered to be excellent material for cartilage regeneration due to the similar structure to ECM and good biocompatibility. However, collagen hydrogels also have several drawbacks, such as low mechanical strength, limited ability to induce stem cell differentiation, and rapid degradation. Thus, there is a demanding need to optimize collagen hydrogels for cartilage regeneration. In this review, we will first briefly introduce the structure of articular cartilage and cartilage defect classification and collagen, then provide an overview of the progress made in research on collagen hydrogels with chondrocytes or stem cells, comprehensively expound the research progress and clinical applications of collagen-based hydrogels that integrate inorganic or organic materials, and finally present challenges for further clinical translation.


Assuntos
Cartilagem Articular , Hidrogéis , Humanos , Hidrogéis/química , Hidrogéis/metabolismo , Hidrogéis/farmacologia , Condrócitos , Colágeno , Regeneração , Engenharia Tecidual
5.
J Pharmacol Sci ; 153(4): 215-220, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37973219

RESUMO

OBJECTIVE: Imeglimin is a novel antidiabetic drug structurally related to metformin. Metformin has been shown to modulate the circadian clock in rat fibroblasts. Accordingly, in the present study, we aimed to determine whether imeglimin can impact the circadian oscillator in mouse embryonic fibroblasts (MEFs). METHODS: MEFs carrying a Bmal1-Emerald luciferase (Bmal1-ELuc) reporter were exposed to imeglimin (0.1 or 1 mM), metformin (0.1 or 1 mM), a nicotinamide phosphoribosyltransferase inhibitor FK866, and/or vehicle. Subsequently, Bmal1-ELuc expression and clock gene mRNA expression levels were measured at 10-min intervals for 55 h and 4-h intervals for 32 h, respectively. RESULTS: Imeglimin significantly prolonged the period (from 26.3 to 30.0 h at 0.1 mM) and dose-dependently increased the amplitude (9.6-fold at 1 mM) of the Bmal1-ELuc expression rhythm; however, metformin exhibited minimal effects on these parameters. Moreover, imeglimin notably impacted the rhythmic mRNA expression of clock genes (Bmal1, Per1, and Cry1). The concurrent addition of FK866 partly inhibited the effects of imeglimin on both Bmal1-ELuc expression and clock gene mRNA expression. CONCLUSION: Collectively, these results reveal that imeglimin profoundly affects the circadian clock in MEFs. Further studies are needed to evaluate whether imeglimin treatment could exert similar effects in vivo.


Assuntos
Relógios Circadianos , Metformina , Ratos , Camundongos , Animais , Relógios Circadianos/genética , Ritmo Circadiano , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Fibroblastos/metabolismo , RNA Mensageiro/metabolismo , Metformina/farmacologia
6.
Complement Ther Med ; 78: 102992, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37805054

RESUMO

OBJECTIVE: To evaluate the effectiveness of acupuncture in relieving diabetic neuropathic pain and to establish a more reliable and efficient foundation for acupuncture practice in diabetes care. METHODS: The Chinese National Knowledge Infrastructure, Wanfang database, Chongqing Weipu, Chinese Biomedical Literature Database, PubMed, Embase, and Cochrane Library were all searched for a randomized controlled trial research of acupuncture for DNP. Two researchers independently performed literature screening, quality evaluation, and data extraction. After selecting studies and extracting data, we conducted the data analysis using RevMan 5.4 and Stata 14.0. The quality was assessed using the Cochrane Risk of Bias Assessment Tool. RESULTS: An extensive review of 19 studies involving 1276 patients up to April 29, 2023, found that acupuncture was successful in improving pain intensity [MD= -1.09; 95% CI (-1.28, -0.89), P < 0.00001], clinical efficacy indicating pain changes [RR= 1.22; 95% CI (1.15, 1.29), P < 0.00001], and clinical neuropathy [MD= -1.55; 95% CI ( -3.00, -0.09), P = 0.04] in DNP patients. Quality of life was also improved, with few side effects reported. CONCLUSION: According to this meta-analysis, acupuncture therapy significantly improved the clinical efficacy of pain intensity, pain changes, and clinical neuropathy in patients with DNP, improved the quality of life of patients to a certain extent, and had lower side effects. This discovery provides evidence-based and practical recommendations for the treatment of DNP patients.


Assuntos
Terapia por Acupuntura , Diabetes Mellitus , Neuropatias Diabéticas , Neuralgia , Humanos , Qualidade de Vida , Terapia por Acupuntura/efeitos adversos , Neuropatias Diabéticas/terapia , Resultado do Tratamento , Neuralgia/terapia , Neuralgia/etiologia , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
J Transl Med ; 21(1): 726, 2023 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-37845765

RESUMO

OBJECTIVES: Gastrointestinal stromal tumors (GISTs) carrying different KIT exon 11 (KIT-11) mutations exhibit varying prognoses and responses to Imatinib. Herein, we aimed to determine whether computed tomography (CT) radiomics can accurately stratify KIT-11 mutation genotypes to benefit Imatinib therapy and GISTs monitoring. METHODS: Overall, 1143 GISTs from 3 independent centers were separated into a training cohort (TC) or validation cohort (VC). In addition, the KIT-11 mutation genotype was classified into 4 categories: no KIT-11 mutation (K11-NM), point mutations or duplications (K11-PM/D), KIT-11 557/558 deletions (K11-557/558D), and KIT-11 deletion without codons 557/558 involvement (K11-D). Subsequently, radiomic signatures (RS) were generated based on the arterial phase of contrast CT, which were then developed as KIT-11 mutation predictors using 1408 quantitative image features and LASSO regression analysis, with further evaluation of its predictive capability. RESULTS: The TC AUCs for K11-NM, K11-PM/D, K11-557/558D, and K11-D ranged from 0.848 (95% CI 0.812-0.884), 0.759 (95% CI 0.722-0.797), 0.956 (95% CI 0.938-0.974), and 0.876 (95% CI 0.844-0.908), whereas the VC AUCs ranged from 0.723 (95% CI 0.660-0.786), 0.688 (95% CI 0.643-0.732), 0.870 (95% CI 0.824-0.918), and 0.830 (95% CI 0.780-0.878). Macro-weighted AUCs for the KIT-11 mutant genotype ranged from 0.838 (95% CI 0.820-0.855) in the TC to 0.758 (95% CI 0.758-0.784) in VC. TC had an overall accuracy of 0.694 (95%CI 0.660-0.729) for RS-based predictions of the KIT-11 mutant genotype, whereas VC had an accuracy of 0.637 (95%CI 0.595-0.679). CONCLUSIONS: CT radiomics signature exhibited good predictive performance in estimating the KIT-11 mutation genotype, especially in prediction of K11-557/558D genotype. RS-based classification of K11-NM, K11-557/558D, and K11-D patients may be an indication for choice of Imatinib therapy.


Assuntos
Tumores do Estroma Gastrointestinal , Humanos , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/genética , Genótipo , Mesilato de Imatinib , Mutação/genética , Proteínas Proto-Oncogênicas c-kit/genética , Receptores Proteína Tirosina Quinases , Estudos Retrospectivos
8.
Front Vet Sci ; 10: 1273944, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37822955

RESUMO

Hexavalent chromium Cr (VI) is one of the most hazardous heavy metals in the environment and is toxic to living organisms causing tissue damage, disruption of the intestinal microbiota and cancer. However, there is little information on the relationship between the Cr (VI) and broiler chickens. The current study was performed to investigate the effect of Cr (VI) on growth performance, serum biochemical analysis, histopathological observations, and metabolomics analysis in broilers. Results show that Cr (VI) exposure significantly decreased the body weight (p < 0.01) and caused liver damages in broilers. With the extension of Cr (VI) action time, the liver appeared obvious pathological changes, including hepatic cord disorder, incomplete hepatocyte additionally, decreased serum biochemical indices of calcium (Ca), phosphorus (P), total protein (TP), phosphatase (ALP), and globin (GLB) significantly (p < 0.01). Moreover, metabolomics analysis indicated that 29 differential metabolites were identified, such as phytosphingosine, L-Serine, 12, 13-DHOME, Alpha-dimorphecolic acid, L-Methionine, L-Phenylalanine, 3-Dehydroshikimate, L-Tyrosine, and N-Acetyl-L-phenylalanine were significantly decreased under the action of Cr (VI) (p < 0.05). These 29 differential metabolites are mainly involved in 35 metabolic pathways, such as aminoacyl-tRNA biosynthesis, phenylalanine metabolism, sphingolipid, and linoleic metabolism. The study revealed that exposure to Cr (VI) resulted in a decrease in growth performance and metabolism, with the hazards and toxicity in broiler chicken. The findings provided new insight and a comprehensive understanding of the relationship between Cr (VI) and broiler chickens.

9.
Redox Biol ; 67: 102922, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37826866

RESUMO

Clinical epidemiological studies have confirmed that tobacco smoking disrupts bone homeostasis and is an independent risk factor for the development of osteoporosis. The low viability and inferior osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) are important etiologies of osteoporosis. However, few basic studies have elucidated the specific mechanisms that tobacco toxins devastated BMSCs and consequently induced or exacerbated osteoporosis. Herein, our clinical data showed the bone mineral density (BMD) values of femoral neck in smokers were significantly lower than non-smokers, meanwhile cigarette smoke extract (CSE) exposure led to a significant decrease of BMD in rats and dysfunction of rat BMSCs (rBMSCs). Transcriptomic analysis and phenotype experiments suggested that the ferroptosis pathway was significantly activated in CSE-treated rBMSCs. Accumulated intracellular reactive oxygen species activated AMPK signaling, furtherly promoted NCOA4-mediated ferritin-selective autophagic processes, increased labial iron pool and lipid peroxidation deposition, and ultimately led to ferroptosis in rBMSCs. Importantly, in vivo utilization of ferroptosis and ferritinophagy inhibitors significantly alleviated BMD loss in CSE-exposed rats. Our study innovatively reveals the key mechanism of smoking-related osteoporosis, and provides a possible route targeting on the perspective of BMSC ferroptosis for future prevention and treatment of smoking-related bone homeostasis imbalance.


Assuntos
Ferroptose , Osteoporose , Ratos , Animais , Osteogênese , Osteoporose/etiologia , Ferro/metabolismo
10.
World J Gastroenterol ; 29(31): 4744-4762, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37664157

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is a clinicopathological entity characterized by intrahepatic ectopic steatosis. As a consequence of increased consumption of high-calorie diet and adoption of a sedentary lifestyle, the incidence of NAFLD has surpassed that of viral hepatitis, making it the most common cause of chronic liver disease globally. Huangqin decoction (HQD), a Chinese medicinal formulation that has been used clinically for thousands of years, has beneficial outcomes in patients with liver diseases, including NAFLD. However, the role and mechanism of action of HQD in lipid metabolism disorders and insulin resistance in NAFLD remain poorly understood. AIM: To evaluate the ameliorative effects of HQD in NAFLD, with a focus on lipid metabolism and insulin resistance, and to elucidate the underlying mechanism of action. METHODS: High-fat diet-induced NAFLD rats and palmitic acid (PA)-stimulated HepG2 cells were used to investigate the effects of HQD and identify its potential mechanism of action. Phytochemicals in HQD were analyzed by high-performance liquid chromatography (HPLC) to identify the key components. RESULTS: Ten primary chemical components of HQD were identified by HPLC analysis. In vivo, HQD effectively prevented rats from gaining body and liver weight, improved the liver index, ameliorated hepatic histological aberrations, decreased transaminase and lipid profile disorders, and reduced the levels of pro-inflammatory factors and insulin resistance. In vitro studies revealed that HQD effectively alleviated PA-induced lipid accumulation, inflammation, and insulin resistance in HepG2 cells. In-depth investigation revealed that HQD triggers Sirt1/NF-κB pathway-modulated lipogenesis and inflammation, contributing to its beneficial actions, which was further corroborated by the addition of the Sirt1 antagonist EX-527 that compromised the favorable effects of HQD. CONCLUSION: In summary, our study confirmed that HQD mitigates lipid metabolism disorders and insulin resistance in NAFLD by triggering the Sirt1/NF-κB pathway.


Assuntos
Resistência à Insulina , Transtornos do Metabolismo dos Lipídeos , Hepatopatia Gordurosa não Alcoólica , Animais , Ratos , NF-kappa B , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/etiologia , Scutellaria baicalensis , Metabolismo dos Lipídeos , Sirtuína 1 , Inflamação , Lipídeos
11.
Arch Esp Urol ; 76(6): 445-453, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37681336

RESUMO

BACKGROUND: Nucleolar prominence is a biomarker of prostate cancer (CaP), and the nucleolar protein block of proliferation 1 (BOP1) participates in the development of CaP, which has great significance for CaP therapy. Thus, this study explored the mechanism of BOP1 in CaP development. METHODS: BOP1 expression levels in the tumor tissues of CaP patients and in PC3 tumor cells were determined. The viability, apoptosis rate of PC3 cells, and apoptosis-related proteins levels were determined to explore the effect of BOP1 on tumor-cell growth in vitro. BOP1 function in the metastasis of PC3 cells was further assessed by Transwell experiment. We also studied the influence of BOP1 on the expression of mitogen-activated protein kinase (MAPK) pathway-related proteins and investigated the regulatory effect of BOP1 on dual-specificity phosphatase 6 (DUSP6). RESULTS: BOP1 expression was upregulated in the tumor tissues and PC3 cells of CaP patients. BOP1 knockout reduced the activity of PC3 cells and induced apoptosis, significantly inhibiting the metastasis of PC3 cells. DUSP6 was overexpressed in tumor tissues and PC3 cells. BOP1 knockout inhibited DUSP6 expression and the MAPK pathway. DUSP6 overexpression reversed the inhibition of BOP1 siRNA (si-BOP1) on PC3 cells and the activated MAPK signaling pathway. CONCLUSIONS: This finding demonstrated that BOP1 promoted CaP progression by regulating the DUSP6/MAPK pathway.


Assuntos
Proteínas Quinases Ativadas por Mitógeno , Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/genética , Transdução de Sinais , Proliferação de Células , Fosfatase 6 de Especificidade Dupla/genética , Proteínas de Ligação a RNA
12.
J Periodontal Res ; 58(5): 1082-1095, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37533377

RESUMO

BACKGROUND AND OBJECTIVES: Cigarette smoking has been reported as an independent risk factor for periodontitis. Tobacco toxins affect periodontal tissue not only locally but also systemically, leading to the deterioration and recurrence of periodontitis. However, the mechanism of cigarette smoke-related periodontitis (CSRP) is unclear and thus lacks targeted treatment strategies. Quercetin, a plant-derived polyphenolic flavonoid, has been reported to have therapeutic effects on periodontitis due to its documented antioxidant activity. This study aimed to evaluate the effects of quercetin on CSRP and elucidated the underlying mechanism. METHODS: The cigarette smoke-related ligature-induced periodontitis mouse model was established by intraperitoneal injection of cigarette smoke extract (CSE) and silk ligation of bilateral maxillary second molars. Quercetin was adopted by gavage as a therapeutic strategy. Micro-computed tomography was used to evaluate the alveolar bone resorption. Immunohistochemistry detected the oxidative stress and autophagy markers in vivo. Cell viability was determined by Cell Counting Kit-8, and oxidative stress levels were tested by 2,7-dichlorodihydrofluorescein diacetate probe and lipid peroxidation malondialdehyde assay kit. Alkaline phosphatase and alizarin red staining were used to determine osteogenic differentiation. Network pharmacology analysis, molecular docking, and western blot were utilized to elucidate the underlying molecular mechanism. RESULTS: Alveolar bone resorption was exacerbated and oxidative stress products were accumulated during CSE exposure in vivo. Oxidative stress damage induced by CSE caused inhibition of osteogenic differentiation in vitro. Quercetin effectively protected the osteogenic differentiation of human periodontal ligament cells (hPDLCs) and periodontal tissue by upregulating the expression of Beclin-1 thus to promote autophagy and reduce oxidative stress damage. CONCLUSION: Our results established a role of oxidative stress damage and autophagy dysfunction in the mechanism of CSE-induced destruction of periodontal tissue and hPDLCs, and provided a potential application value of quercetin to ameliorate CSRP.


Assuntos
Reabsorção Óssea , Fumar Cigarros , Periodontite , Camundongos , Animais , Humanos , Quercetina/farmacologia , Quercetina/uso terapêutico , Osteogênese , Fumar Cigarros/efeitos adversos , Simulação de Acoplamento Molecular , Microtomografia por Raio-X , Periodontite/metabolismo , Diferenciação Celular , Autofagia , Células Cultivadas
13.
Arch. esp. urol. (Ed. impr.) ; 76(6): 445-453, 28 aug. 2023. ilus, graf
Artigo em Inglês | IBECS | ID: ibc-224897

RESUMO

Background: Nucleolar prominence is a biomarker of prostate cancer (CaP), and the nucleolar protein block of proliferation 1 (BOP1) participates in the development of CaP, which has great significance for CaP therapy. Thus, this study explored the mechanism of BOP1 in CaP development. Methods: BOP1 expression levels in the tumor tissues of CaP patients and in PC3 tumor cells were determined. The viability, apoptosis rate of PC3 cells, and apoptosis-related proteins levels were determined to explore the effect of BOP1 on tumor-cell growth in vitro. BOP1 function in the metastasis of PC3 cells was further assessed by Transwell experiment. We also studied the influence of BOP1 on the expression of mitogen-activated protein kinase (MAPK) pathway-related proteins and investigated the regulatory effect of BOP1 on dual-specificity phosphatase 6 (DUSP6). Results: BOP1 expression was upregulated in the tumor tissues and PC3 cells of CaP patients. BOP1 knockout reduced the activity of PC3 cells and induced apoptosis, significantly inhibiting the metastasis of PC3 cells. DUSP6 was overexpressed in tumor tissues and PC3 cells. BOP1 knockout inhibited DUSP6 expression and the MAPK pathway. DUSP6 overexpression reversed the inhibition of BOP1 siRNA (si-BOP1) on PC3 cells and the activated MAPK signaling pathway. Conclusions: This finding demonstrated that BOP1 promoted CaP progression by regulating the DUSP6/MAPK pathway (AU)


Assuntos
Humanos , Masculino , Neoplasias da Próstata/sangue , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Fosfatase 6 de Especificidade Dupla/metabolismo , Transdução de Sinais , Proliferação de Células , Biomarcadores Tumorais , Apoptose
14.
ACS Biomater Sci Eng ; 9(8): 4735-4746, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37428711

RESUMO

Extracellular matrix (ECM) stiffness is a key stimulus affecting cellular differentiation, and osteoblasts are also in a three-dimensional (3D) stiff environment during the formation of bone tissues. However, it remains unclear how cells perceive matrix mechanical stiffness stimuli and translate them into intracellular signals to affect differentiation. Here, for the first time, we constructed a 3D culture environment by GelMA hydrogels with different amino substitution degrees and found that Piezo1 expression was significantly stimulated by the stiff matrix with high substitution; meanwhile, the expressions of osteogenic markers OSX, RUNX2, and ALP were also observably improved. Moreover, knockdown of Piezo1 in the stiff matrix revealed significant reduction of the abovementioned osteogenic markers. In addition, in this 3D biomimetic ECM, we also observed that Piezo1 can be activated by the static mechanical conditions of the stiff matrix, leading to the increase of the intracellular calcium content and accompanied with a continuous change in cellular energy levels as ATP was consumed during cellular differentiation. More surprisingly, we found that in the 3D stiff matrix, intracellular calcium as a second messenger promoted the activation of the AMP-activated protein kinase (AMPK) and unc-51-like autophagy-activated kinase 1 (ULK1) axis and modestly modulated the level of autophagy, bringing it more similar to differentiated osteoblasts, with increased ATP energy metabolism consumption. Our study innovatively clarifies the regulatory role of the mechanosensitive ion channel Piezo1 in a static mechanical environment on cellular differentiation and verifies the activation of the AMPK-ULK1 axis in the cellular ATP energy metabolism and autophagy level. Collectively, our research develops the understanding of the interaction mechanisms of biomimetic extracellular matrix biomaterials and cells from a novel perspective and provides a theoretical basis for bone regeneration biomaterials design and application.


Assuntos
Proteínas Quinases Ativadas por AMP , Osteogênese , Trifosfato de Adenosina , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia/genética , Materiais Biocompatíveis , Cálcio , Diferenciação Celular/genética , Osteogênese/genética , Animais , Camundongos
15.
J Nanobiotechnology ; 21(1): 229, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37468894

RESUMO

The inflammatory immune environment surrounding titanium bone implants determines the formation of osseointegration, and nanopatterning on implant surfaces modulates the immune microenvironment in the implant region. Among many related mechanisms, the mechanism by which nanopatterning controls macrophage inflammatory response still needs to be elucidated. In this paper, we found that inhibition of the nuclear envelope protein lamin A/C by titania nanotubes (TNTs) reduced the macrophage inflammatory response. Knockdown of lamin A/C reduced macrophage inflammatory marker expression, while overexpression of lamin A/C significantly elevated inflammatory marker expression. We further found that suppression of lamin A/C by TNTs limited actin polymerization, thereby reducing the nuclear translocation of the actin-dependent transcriptional cofactor MRTF-A, which subsequently reduced the inflammatory response. In addition, emerin, which is a key link between lamin A/C and actin, was delocalized from the nucleus in response to mechanical stimulation by TNTs, resulting in reduced actin organization. Under inflammatory conditions, TNTs exerted favourable osteoimmunomodulatory effects on the osteogenic differentiation of mouse bone marrow-derived stem cells (mBMSCs) in vitro and osseointegration in vivo. This study shows and confirms for the first time that lamin A/C-mediated nuclear mechanotransduction controls macrophage inflammatory response, and this study provides a theoretical basis for the future design of immunomodulatory nanomorphologies on the surface of metallic bone implants.


Assuntos
Lamina Tipo A , Nanotubos , Camundongos , Animais , Actinas , Osteogênese , Mecanotransdução Celular , Macrófagos , Titânio/farmacologia , Propriedades de Superfície
16.
Mater Today Bio ; 20: 100661, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37229211

RESUMO

Matrix stiffness plays an important role in determining cell differentiation. The expression of cell differentiation-associated genes can be regulated by chromatin remodeling-mediated DNA accessibility. However, the effect of matrix stiffness on DNA accessibility and its significance for cell differentiation have not been investigated. In this study, gelatin methacryloyl (GelMA) hydrogels with different degrees of substitution were used to simulate soft, medium, and stiff matrices, and it was found that a stiff matrix promoted osteogenic differentiation of MC3T3-E1 cells by activating the Wnt pathway. In the soft matrix, the acetylation level of histones in cells was decreased, and chromatin condensed into a closed conformation, affecting the activation of ß-catenin target genes (Axin2, c-Myc). Histone deacetylase inhibitor (TSA) was used to decondense chromatin. However, there was no significant increase in the expression of ß-catenin target genes and the osteogenic protein Runx2. Further studies revealed that ß-catenin was restricted to the cytoplasm due to the downregulation of lamin A/C in the soft matrix. Overexpression of lamin A/C and concomitant treatment of cells with TSA successfully activated ß-catenin/Wnt signaling in cells in the soft matrix. The results of this innovative study revealed that matrix stiffness regulates cell osteogenic differentiation through multiple pathways, which involve complex interactions between transcription factors, epigenetic modifications of histones, and the nucleoskeleton. This trio is critical for the future design of bionic extracellular matrix biomaterials.

17.
Front Pharmacol ; 14: 1182788, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37089945

RESUMO

Lenvatinib is an oral tyrosine kinase inhibitor that acts on multiple receptors involved in angiogenesis. Lenvatinib is a standard agent for the treatment of several types of advanced cancers; however, it frequently causes muscle-related adverse reactions. Our previous study revealed that lenvatinib treatment reduced carnitine content and the expression of carnitine-related and oxidative phosphorylation (OXPHOS) proteins in the skeletal muscle of rats. Therefore, this study aimed to evaluate the effects of L-carnitine on myotoxic and anti-angiogenic actions of lenvatinib. Co-administration of L-carnitine in rats treated with lenvatinib for 2 weeks completely prevented the decrease in carnitine content and expression levels of carnitine-related and OXPHOS proteins, including carnitine/organic cation transporter 2, in the skeletal muscle. Moreover, L-carnitine counteracted lenvatinib-induced protein synthesis inhibition, mitochondrial dysfunction, and cell toxicity in C2C12 myocytes. In contrast, L-carnitine had no influence on either lenvatinib-induced inhibition of vascular endothelial growth factor receptor 2 phosphorylation in human umbilical vein endothelial cells or angiogenesis in endothelial tube formation and mouse aortic ring assays. These results suggest that L-carnitine supplementation could prevent lenvatinib-induced muscle toxicity without diminishing its antineoplastic activity, although further clinical studies are needed to validate these findings.

18.
NPJ Digit Med ; 6(1): 41, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36918730

RESUMO

Optimal bowel preparation is a prerequisite for a successful colonoscopy; however, the rate of inadequate bowel preparation remains relatively high. In this study, we establish a smartphone app that assesses patient bowel preparation using an artificial intelligence (AI)-based prediction system trained on labeled photographs of feces in the toilet and evaluate its impact on bowel preparation quality in colonoscopy outpatients. We conduct a prospective, single-masked, multicenter randomized clinical trial, enrolling outpatients who own a smartphone and are scheduled for a colonoscopy. We screen 578 eligible patients and randomize 524 in a 1:1 ratio to the control or AI-driven app group for bowel preparation. The study endpoints are the percentage of patients with adequate bowel preparation and the total BBPS score, compliance with dietary restrictions and purgative instructions, polyp detection rate, and adenoma detection rate (secondary). The prediction system has an accuracy of 95.15%, a specificity of 97.25%, and an area under the curve of 0.98 in the test dataset. In the full analysis set (n = 500), adequate preparation is significantly higher in the AI-driven app group (88.54 vs. 65.59%; P < 0.001). The mean BBPS score is 6.74 ± 1.25 in the AI-driven app group and 5.97 ± 1.81 in the control group (P < 0.001). The rates of compliance with dietary restrictions (93.68 vs. 83.81%, P = 0.001) and purgative instructions (96.05 vs. 84.62%, P < 0.001) are significantly higher in the AI-driven app group, as is the rate of additional purgative intake (26.88 vs. 17.41%, P = 0.011). Thus, our AI-driven smartphone app significantly improves the quality of bowel preparation and patient compliance.

19.
Water Res ; 233: 119728, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36822112

RESUMO

The effect of reservoir construction on nutrient dynamics is well recognized, at flood event-scale influence of reservoir flood regulation on nutrient transport however has received less attention. Taking the Three Gorges Reservoir (TGR) in the Changjiang River as an example, during the TGR's regulation on a flood in Sep., 2021, this study collected water samples along the mainstream of the reservoir as well as pre/post-dam, with the aim to identify the impact of flood regulation on nutrient (nitrogen and phosphorus) distribution and transportation. Results show that nitrate nitrogen (NO3N) and particulate phosphorus (PP) were the main fraction of the total nitrogen (TN) and total phosphorus (TP) with the proportion of 46.5%-95.6% and 57.4%-81.6%, respectively. N and P responded different to flood regulation: (i) along the stream P concentration significantly decreased due to PP deposited with sediment while N concentration barely changed during flood regulation; (ii) P concentration was significantly higher at post-dam section than at pre-dam section, while N concentration maintained the same. The diffed response to flood regulation caused TN/TP ratio increased from 4 to 8 in the reservoir tail to over 20 near the dam, which probably arise eutrophication in the reservoir head area. This study reveals the influence of flood regulation on nutrient transport in flood event and provides scientific basis for reservoir management.


Assuntos
Poluentes Químicos da Água , Água , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Inundações , Fósforo/análise , Rios , Nitrogênio/análise , Nutrientes , China
20.
Adv Mater ; 35(19): e2211584, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36840984

RESUMO

Achieving a periodic domain structure in ferroelectric materials to tailor the macroscopic properties or realize new functions has always been a hot topic. However, methods to construct periodic domain structures, such as epitaxial growth, direct writing by scanning tips, and the patterned electrode method, are difficult or inefficient to implement in emerging molecular ferroelectrics, which have the advantages of lightweight, flexibility, biocompatibility, etc. An efficient method for constructing and controlling periodic domain structures is urgently needed to facilitate the development of molecular ferroelectrics in nanoelectronic devices. In this work, it is demonstrated that large-area, periodic and controllable needle-like domain structures can be achieved in thin films of the molecular ferroelectric trimethylchloromethyl ammonium trichlorocadmium (TMCM-CdCl3 ) upon the application of tensile strain. The domain evolution under various tensile strains can be clearly observed, and such processes are accordingly identified. Furthermore, the domain wall exhibits a superior piezoelectric response, with up to fivefold enhancement compared to that of the pristine samples. Such large-area tunable periodic domain structure and abnormally strong piezoresponse are not only of great interests in fundamental studies, but also highly important in the future applications in functional molecular materials.

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