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1.
Gen Comp Endocrinol ; 332: 114180, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36455644

RESUMO

The mammalian melanocortin-5 receptors (MC5Rs) are involved in various functions, including exocrine gland secretion, glucose uptake, adipocyte lipolysis, and immunity. However, the physiological role of fish Mc5r is rarely studied. Melanocortin-2 receptor accessory protein 2 (MRAP2) modulates pharmacological properties of melanocortin receptors. Herein, to lay the foundation for future physiological studies, we cloned the orange-spotted grouper (Epinephelus coioides) mc5r, with a 1008 bp open reading frame and a predicted protein of 334 amino acids. Grouper mc5r had abundant expression in the brain, skin, and kidney. Four ligands could bind to grouper Mc5r and dose-dependently increase intracellular cAMP levels. Grouper Mrap2 did not affect binding affinity or potency of Mc5r; however, grouper Mrap2 decreased cell surface expression and maximal binding of Mc5r. Mrap2 also significantly decreased the maximal response to a superpotent agonist but not the endogenous agonist. This study provided new data on fish Mc5r pharmacology and its regulation by Mrap2.


Assuntos
Bass , Doenças dos Peixes , Animais , Bass/genética , Regulação da Expressão Gênica , Sequência de Aminoácidos , Receptores de Melanocortina/metabolismo , Proteínas de Peixes/metabolismo , Filogenia , Clonagem Molecular , Mamíferos/metabolismo
2.
Int J Mol Sci ; 24(20)2023 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-37894875

RESUMO

Tendon aging is associated with an increasing prevalence of tendon injuries and/or chronic tendon diseases, such as tendinopathy, which affects approximately 25% of the adult population. Aged tendons are often characterized by a reduction in the number and functionality of tendon stem/progenitor cells (TSPCs), fragmented or disorganized collagen bundles, and an increased deposition of glycosaminoglycans (GAGs), leading to pain, inflammation, and impaired mobility. Although the exact pathology is unknown, overuse and microtrauma from aging are thought to be major causative factors. Due to the hypovascular and hypocellular nature of the tendon microenvironment, healing of aged tendons and related injuries is difficult using current pain/inflammation and surgical management techniques. Therefore, there is a need for novel therapies, specifically cellular therapy such as cell rejuvenation, due to the decreased regenerative capacity during aging. To augment the therapeutic strategies for treating tendon-aging-associated diseases and injuries, a comprehensive understanding of tendon aging pathology is needed. This review summarizes age-related tendon changes, including cell behaviors, extracellular matrix (ECM) composition, biomechanical properties and healing capacity. Additionally, the impact of conventional treatments (diet, exercise, and surgery) is discussed, and recent advanced strategies (cell rejuvenation) are highlighted to address aged tendon healing. This review underscores the molecular and cellular linkages between aged tendon biomechanical properties and the healing response, and provides an overview of current and novel strategies for treating aged tendons. Understanding the underlying rationale for future basic and translational studies of tendon aging is crucial to the development of advanced therapeutics for tendon regeneration.


Assuntos
Envelhecimento , Tendões , Adulto , Humanos , Fenômenos Biomecânicos , Tendões/fisiologia , Envelhecimento/patologia , Inflamação/patologia , Dor/patologia , Biologia
3.
Int J Psychiatry Clin Pract ; 26(4): 337-342, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35023429

RESUMO

BACKGROUND: This study is the first to assess the safety and therapeutic efficacy of vagus nerve stimulation (VNS) as an adjunctive treatment for Chinese patients suffering from treatment-resistant depression (TRD). METHODS: A total of seven patients with TRD underwent surgical implantation of a VNS device were followed over a 9-month period. The 24-item Hamilton Rating Scale for Depression (HAMD-24) and the 14-item Hamilton Anxiety Scale (HAMA) were used to assess depressive and anxiety symptoms, respectively. Neurocognitive function was measured with the Wechsler Adult Intelligence Scale (WAIS) and the Wechsler Memory Scale (WMS). RESULTS: After 3 months of treatment with VNS, the antidepressant response and remission rates were 42.9% and 28.6%, respectively. After 9 months of treatment with VNS, the response and remission rates increased to 85.7% and 57.1%, respectively. Significant time main effects were identified for HAMD-24 scores, HAMA scores, the WMS memory quotient, and the full intelligence quotients measured with the WAIS (all ps < 0.05). The most frequent adverse effects of VNS treatment were voice alteration (100%) and cough frequency increase (71.4%). CONCLUSION: This preliminary study indicated that adjunctive VNS was effective and safe in treating Chinese patients who were suffering from TRD, and its efficacy increased with time.Key pointsThere is positive evidence to support the role of VNS as an adjunctive treatment in Chinese patients with TRD.The antidepressant efficacy of adjunctive VNS for Chinese patients with TRD increased with time.The most frequent adverse effects of VNS treatment were voice alteration and cough frequency increase.


Assuntos
Estimulação do Nervo Vago , Adulto , Humanos , Estimulação do Nervo Vago/efeitos adversos , Depressão , Tosse/tratamento farmacológico , Resultado do Tratamento , Antidepressivos/uso terapêutico
4.
Gen Comp Endocrinol ; 285: 113291, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31568758

RESUMO

Melanocortin-1 receptor (MC1R) has important roles in regulating pigmentation and inflammation. Melanocortin receptor accessory protein 2 (MRAP2) modulates trafficking, ligand binding, and signaling of mammalian melanocortin receptors. However, the effect of MRAP2 on fish MC1R has not been extensively studied. Herein, we cloned the orange-spotted grouper (Epinephelus coioides) mc1r, which had a 972 bp open reading frame encoding a putative protein of 323 amino acids. Grouper mc1r was mainly expressed in the brain, skin, testis, spleen, head kidney, and kidney. EcoMC1R showed high constitutive activities in both Gs-cAMP and ERK1/2 pathways, which could be differentially modulated by grouper MRAP2 (EcoMRAP2). Three agonists, including α-melanocyte-stimulating hormone (MSH), ß-MSH, and ACTH, could bind to EcoMC1R and dose-dependently increase intracellular cAMP production. EcoMRAP2 had no effect on the IC50 in binding assay or EC50 in cAMP assay; however, it dose-dependently decreased the cell surface expression and maximal response to the three agonists. EcoMRAP2 increased basal ERK1/2 activation but did not alter α-MSH-stimulated ERK1/2 activation. This study extends the knowledge base of fish MC1R pharmacology and its regulation by MRAP2.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Bass/metabolismo , Proteínas de Peixes/metabolismo , Receptor Tipo 1 de Melanocortina/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Bass/genética , AMP Cíclico/metabolismo , Regulação da Expressão Gênica , Células HEK293 , Humanos , Ligantes , Sistema de Sinalização das MAP Quinases , Filogenia , Receptor Tipo 1 de Melanocortina/química , Receptor Tipo 1 de Melanocortina/genética , Transdução de Sinais/efeitos dos fármacos
5.
Psychiatr Q ; 91(3): 669-679, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32144640

RESUMO

Vagus nerve stimulation (VNS) has been increasingly studied in treating treatment-resistant depression (TRD), but the findings have been mixed. This updated meta-analysis was conducted to examine the efficacy and safety of adjunctive VNS for TRD. Controlled studies reporting on the efficacy and safety of adjunctive VNS for TRD were screened, identified and analyzed. Standardized mean difference (SMD), risk ratio (RR) and their 95% confidence intervals (CIs) were analyzed using RevMan version 5.3. Three controlled studies with a total of 1048 patients with TRD compared VNS (n = 622) with control (n = 426) groups. Only one study was rated as 'high quality' using the Jadad scale. Adjunctive VNS was significantly superior to the control group regarding study-defined response [SMD:1.96 (95%CI:1.60, 2.40), P < 0.00001, I2 = 0%]. Patient-reported voice alteration occurred more frequently with adjunctive VNS for patients with TRD. No significant group differences were found regarding discontinuation due to any reason [RR:0.50 (95%CI:0.12, 2.09), P = 0.34, I2 = 85%]. Adjunctive VNS appeared to be effective and relatively safe treatment for TRD. Further randomized controlled trials are needed to confirm the efficacy and safety of VNS for TRD.


Assuntos
Transtorno Depressivo Resistente a Tratamento/terapia , Avaliação de Resultados em Cuidados de Saúde , Estimulação do Nervo Vago , Humanos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Estimulação do Nervo Vago/efeitos adversos , Estimulação do Nervo Vago/estatística & dados numéricos
6.
Gen Comp Endocrinol ; 284: 113234, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31398355

RESUMO

Melanocortin-4 receptor (MC4R) and melanocortin receptor accessory protein 2 (MRAP2) play important roles in the melanocortin system, and interaction of MC4R and MRAP2 is suggested to play pivotal role in energy balance of vertebrates. Orange-spotted grouper (Epinephelus coioides) is a widely cultured marine fish with high economic value in Asia. To explore potential interaction between grouper MC4R and MRAP2, herein we cloned grouper mc4r and mrap2. Grouper mc4r consisted of a 981 bp ORF encoding a putative protein of 327 amino acids, while the grouper mrap2 consisted of a 696 bp ORF encoding a putative protein of 232 amino acids. Sequence and phylogenetic analysis revealed that the grouper MC4R and MRAP2 were highly homologous at amino acid levels to several teleost MC4Rs and MRAP2s, respectively. qRT-PCR results showed that both mc4r and mrap2 were expressed primarily in the central nervous system. In the periphery, these genes were expressed more widely in male fish. The cloned grouper MC4R was functional, exhibiting high constitutive activity in cAMP pathway, capable of binding to three peptide agonists and increasing intracellular cAMP production dose-dependently. MRAP2 significantly decreased basal and agonist-stimulated cAMP signaling. MRAP2 also increased basal ERK1/2 activation but decreased ligand-induced stimulation when expressed at high levels. These data will facilitate future investigation of these molecules in regulating diverse physiological processes in orange-spotted grouper.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Bass/metabolismo , Receptor Tipo 4 de Melanocortina/metabolismo , Transdução de Sinais , Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Bass/genética , AMP Cíclico/metabolismo , Regulação da Expressão Gênica , Células HEK293 , Humanos , Ligantes , Filogenia , Receptor Tipo 4 de Melanocortina/genética
7.
Clin Exp Pharmacol Physiol ; 45(1): 10-15, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28755509

RESUMO

There is strong evidence of roles of the hypothalamus-pituitary-adrenal axis and nitric oxide (NO) synthase-NO system in depression, but the relationship between them is unknown. The aim of this study, therefore, was to elucidate whether there is any correlation between NO and corticotropin-releasing hormone (CRH) in major depressive disorder (MDD) patients. In 16 outpatients with MDD and 18 healthy controls, the plasma amino acids citrulline (Cit) and arginine (Arg) were determined by high-performance liquid chromatography, and CRH levels was measured by radioimmunoassay. The Cit/Arg ratio was calculated as an index of NO synthesis. Correlations between NO and CRH were examined with the Spearman test. Before treatment, no significant correlation was observed between the plasma NO level and CRH levels in MDD patients. The plasma NO levels were significantly higher in MDD patients. A significant correlation was found between NO levels and Hamilton Depression Rating Scale (HAMD) scores in MDD patients. The plasma CRH levels were significantly higher in MDD patients than in controls. After monotherapy for 2 months, the NO levels had dramatically declined but were also higher than those in the controls. This study is the first report of the absence of a significant correlation between plasma NO and CRH levels, although both levels are elevated in MDD patients. Furthermore, the strong links between the plasma NO levels and the HAMD scores, as well as the increased NO reduction after remission, suggest that NO plays a key role in depression and may be an indicator of therapeutic success.


Assuntos
Hormônio Liberador da Corticotropina/sangue , Transtorno Depressivo Maior/sangue , Óxido Nítrico/sangue , Transtorno Depressivo Maior/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
8.
J Environ Sci Health B ; 53(12): 777-785, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30199317

RESUMO

Bacillus spp. have long been used as biocontrol agents because of their efficient broad-spectrum antimicrobial activity. We identified a novel strain of Bacillus atrophaeus, named JZB120050, from soil. B. atrophaeus JZB120050 had a strong inhibitory effect against Botrytis cinerea and many other phytopathogens. Gas chromatography-mass spectrometry showed that B. atrophaeus JZB120050 produced many secondary metabolites, such as alkanes, alkenes and acids; some of which were related to pathogen inhibition. Enzyme activity analysis showed that B. atrophaeus JZB120050 secreted cell-wall-degrading enzymes, including chitinase, glucanase and protease, which degraded fungal cell walls. Both the novel glucanase gene bglu and chitinase gene chit1 were cloned and heterologously expressed in Escherichia coli and the products showed strong enzyme activity. In addition, B. atrophaeus JZB120050 secreted siderophores and formed a significant biofilm. Future studies should focus on these antimicrobial factors to facilitate widespread application in the field of agricultural biocontrol.


Assuntos
Bacillus/fisiologia , Agentes de Controle Biológico , Bacillus/enzimologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biofilmes , Botrytis , Quitinases/metabolismo , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Peptídeo Hidrolases/metabolismo , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Metabolismo Secundário
9.
World J Surg Oncol ; 15(1): 186, 2017 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-29041974

RESUMO

BACKGROUND: We investigated the functional status of adult supratentorial superficial low-grade glioma (ASS-LGG) after surgery and analyzed its relevant factors to guide the therapeutic strategy and improve the life quality of these patients. METHODS: Clinical materials from January 2008 to December 2010 in 104 adults with ASS-LGG were analyzed retrospectively. The follow-up period ranged from 6 months to 1.5 years. The logistic regression was used to evaluate the preoperative and postoperative variation of functional status in patients to disclose the relevant factors affecting postoperative functional status, such as age, gender, the duration of symptom, size and location of the tumor, hemisphere, resection degree, and tumor pathologic grade and preoperative Karnofsky performance status (Pre-KPS). RESULTS: Four out of nine candidate factors are related to the postoperative functional status. They are age less than 40 years, the size of tumor less than 5 cm in diameter, tumor located in the right hemisphere, and limited resection of tumor in the eloquent area. CONCLUSIONS: It seems more meaningful to evaluate the functional status of the patients with ASS-LGG on the basis of these clinical features, involving age, tumor size, location, and extent of resection.


Assuntos
Glioma/cirurgia , Avaliação de Estado de Karnofsky , Procedimentos Neurocirúrgicos/efeitos adversos , Qualidade de Vida , Neoplasias Supratentoriais/cirurgia , Adulto , Fatores Etários , Feminino , Seguimentos , Glioma/patologia , Humanos , Masculino , Gradação de Tumores , Procedimentos Neurocirúrgicos/métodos , Período Pós-Operatório , Prognóstico , Estudos Retrospectivos , Neoplasias Supratentoriais/patologia
10.
J Am Chem Soc ; 138(18): 6020-7, 2016 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-27099162

RESUMO

A self-healing dielectric elastomer is achieved by the incorporation of metal-ligand coordination as cross-linking sites in nonpolar polydimethylsiloxane (PDMS) polymers. The ligand is 2,2'-bipyridine-5,5'-dicarboxylic amide, while the metal salts investigated here are Fe(2+) and Zn(2+) with various counteranions. The kinetically labile coordination between Zn(2+) and bipyridine endows the polymer fast self-healing ability at ambient condition. When integrated into organic field-effect transistors (OFETs) as gate dielectrics, transistors with FeCl2 and ZnCl2 salts cross-linked PDMS exhibited increased dielectric constants compared to PDMS and demonstrated hysteresis-free transfer characteristics, owing to the low ion conductivity in PDMS and the strong columbic interaction between metal cations and the small Cl(-) anions which can prevent mobile anions drifting under gate bias. Fully stretchable transistors with FeCl2-PDMS dielectrics were fabricated and exhibited ideal transfer characteristics. The gate leakage current remained low even after 1000 cycles at 100% strain. The mechanical robustness and stable electrical performance proved its suitability for applications in stretchable electronics. On the other hand, transistors with gate dielectrics containing large-sized anions (BF4(-), ClO4(-), CF3SO3(-)) displayed prominent hysteresis due to mobile anions drifting under gate bias voltage. This work provides insights on future design of self-healing stretchable dielectric materials based on metal-ligand cross-linked polymers.


Assuntos
Metais/química , Polímeros/química , 2,2'-Dipiridil , Cloretos/química , Reagentes de Ligações Cruzadas , Dimetilpolisiloxanos/química , Elasticidade , Eletrônica , Compostos Ferrosos/química , Ligantes , Compostos de Zinco/química
11.
Lab Invest ; 95(9): 1056-70, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26098000

RESUMO

The miR-19 family (miR-19a and miR-19b-1) are key oncogenic components of the miR-17-92 cluster. Overexpression of miR-19 is strongly associated with cancer invasion and metastasis, and poor prognosis of cancer patients. However, the underlying mechanisms remain largely unknown. In the present study, we found that enforced expression of miR-19 including miR-19a and miR-19b-1 triggered epithelial-mesenchymal transition (EMT) of lung cancer cells A549 and HCC827 as shown by mesenchymal-like morphological conversion, downregulation of epithelial proteins (e.g., E-cadherin, ZO-1 (zona occludens 1), and α-catenin), upregulation of mesenchymal proteins (e.g., vimentin, fibronectin 1, N-cadherin, and snail1), formation of stress fibers, and reduced cell adhesion. In addition, enhanced migration and invasion were observed in the cancer cells A549 and HCC827 undergoing EMT. In contrast, silencing of endogenous miR-19 reversed EMT and reduced the migration and invasion abilities of A549 and HCC827 cells. DNA microarray results revealed significant changes of the expression of genes related to EMT, migration, and metastasis of miR-19-expressing A549 cells. Moreover, siRNA-mediated knockdown of PTEN, a target of miR-19, also resulted in EMT, migration, and invasion of A549 and HCC827 cells, suggesting that PTEN is involved in miR-19-induced EMT, migration and invasion of lung cancer cells. Furthermore, lung cancer cells undergoing EMT induced by miR-19 demonstrated reduced proliferation in vitro and in vivo, and enhanced resistance to apoptosis caused by TNF-α. Taken together, these findings suggest that miR-19 triggers EMT, which has an important role in the invasion and migration of lung cancer cells, accompanied by the reduced proliferation of cells.


Assuntos
Transição Epitelial-Mesenquimal/fisiologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Neoplasias Pulmonares/fisiopatologia , MicroRNAs/metabolismo , Animais , Antígenos CD/metabolismo , Western Blotting , Caderinas/metabolismo , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Fibronectinas/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Luciferases , Camundongos , Camundongos Endogâmicos BALB C , MicroRNAs/farmacologia , Análise de Sequência com Séries de Oligonucleotídeos , Interferência de RNA , Fatores de Transcrição da Família Snail , Sais de Tetrazólio , Tiazóis , Fatores de Transcrição/metabolismo , Ensaio Tumoral de Célula-Tronco , Vimentina/metabolismo , Proteína da Zônula de Oclusão-1/metabolismo , alfa Catenina/metabolismo
12.
Angew Chem Int Ed Engl ; 53(34): 9086-9, 2014 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-24943291

RESUMO

Two new tricyclic 1,2-azaboratabisnorcaradiene molecules (1 b and 2 b) generated through the photoisomerization of N-methyl-2-phenylimidazolyl-chelated dimesitylboranes (1 a and 2 a) have been found to undergo unusual photoisomerization, producing the first examples of 1,2-azaborabenzotropilidenes (1 c and 2 c), accompanied by a distinct color change, upon irradiation at 350 nm. Compounds 1 c and 2 c contain a conjugated alkylideneborane unit and can be fully reverted back to 1 b and 2 b, and subsequently to 1 a and 2 a upon heating. The mechanistic pathway of the new isomerism has been established to involve "walk" rearrangements by DFT computational studies.

13.
Sci Rep ; 14(1): 8292, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594304

RESUMO

The spread of blast dust throughout the tunnel becomes a common problem in drill and blast tunneling,the key to breaking through the problem is the creation of a dust control area on the working face.In view of this key problem, a wet string grid dust removal crawler vehicle was developed, the power of the vehicle came from the diesel generator, and further, the air cooler of the diesel generator was used to generate airflow, and the suction process formed by the on-board axial flow fan was coupled to create a dust control area of the working face after blasting.The results show that when the frequency of the axial flow fan is adjusted to 30 Hz, the airflow speed of the wet chord grid section reaches 3.34 m/s, and the dust removal efficiency is the highest, with a value of 94.3%.Compared with the non-use of the dust removal vehicle, when the air outlet of the air cooler is front, horizontal front, horizontal rear, the dust concentration is reduced by 74.37, 92.39 and 50.53%.Finally, the optimized wet grid dust removal crawler was installed in the Dading tunnel, and the actual dust reduction efficiency was about 78.49%. The results obtained provide an important technical way to improve the working environment of the drilling and blasting construction tunnel.

14.
Bioact Mater ; 36: 221-237, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38481565

RESUMO

A significant clinical challenge in large-to-massive rotator cuff tendon injuries is the need for sustaining high mechanical demands despite limited tissue regeneration, which often results in clinical repair failure with high retear rates and long-term functional deficiencies. To address this, an innovative tendon substitute named "BioTenoForce" is engineered, which uses (i) tendon extracellular matrix (tECM)'s rich biocomplexity for tendon-specific regeneration and (ii) a mechanically robust, slow degradation polyurethane elastomer to mimic native tendon's physical attributes for sustaining long-term shoulder movement. Comprehensive assessments revealed outstanding performance of BioTenoForce, characterized by robust core-shell interfacial bonding, human rotator cuff tendon-like mechanical properties, excellent suture retention, biocompatibility, and tendon differentiation of human adipose-derived stem cells. Importantly, BioTenoForce, when used as an interpositional tendon substitute, demonstrated successful integration with regenerative tissue, exhibiting remarkable efficacy in repairing large-to-massive tendon injuries in two animal models. Noteworthy outcomes include durable repair and sustained functionality with no observed breakage/rupture, accelerated recovery of rat gait performance, and >1 cm rabbit tendon regeneration with native tendon-like biomechanical attributes. The regenerated tissues showed tendon-like, wavy, aligned matrix structure, which starkly contrasts with the typical disorganized scar tissue observed after tendon injury, and was strongly correlated with tissue stiffness. Our simple yet versatile approach offers a dual-pronged, broadly applicable strategy that overcomes the limitations of poor regeneration and stringent biomechanical requirements, particularly essential for substantial defects in tendon and other load-bearing tissues.

15.
Bioact Mater ; 37: 439-458, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38698918

RESUMO

Facile and rapid 3D fabrication of strong, bioactive materials can address challenges that impede repair of large-to-massive rotator cuff tears including personalized grafts, limited mechanical support, and inadequate tissue regeneration. Herein, we developed a facile and rapid methodology that generates visible light-crosslinkable polythiourethane (PHT) pre-polymer resin (∼30 min at room temperature), yielding 3D-printable scaffolds with tendon-like mechanical attributes capable of delivering tenogenic bioactive factors. Ex vivo characterization confirmed successful fabrication, robust human supraspinatus tendon (SST)-like tensile properties (strength: 23 MPa, modulus: 459 MPa, at least 10,000 physiological loading cycles without failure), excellent suture retention (8.62-fold lower than acellular dermal matrix (ADM)-based clinical graft), slow degradation, and controlled release of fibroblast growth factor-2 (FGF-2) and transforming growth factor-ß3 (TGF-ß3). In vitro studies showed cytocompatibility and growth factor-mediated tenogenic-like differentiation of mesenchymal stem cells. In vivo studies demonstrated biocompatibility (3-week mouse subcutaneous implantation) and ability of growth factor-containing scaffolds to notably regenerate at least 1-cm of tendon with native-like biomechanical attributes as uninjured shoulder (8-week, large-to-massive 1-cm gap rabbit rotator cuff injury). This study demonstrates use of a 3D-printable, strong, and bioactive material to provide mechanical support and pro-regenerative cues for challenging injuries such as large-to-massive rotator cuff tears.

16.
Acta Biomater ; 176: 99-115, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38142795

RESUMO

Despite the growing clinical use of extracellular matrix (ECM)-based biomaterials for tendon repair, undesired healing outcomes or complications have frequently been reported. A major scientific challenge has been the limited understanding of their functional compositions and mechanisms of action due to the complex nature of tendon ECM. Previously, we have reported a soluble ECM fraction from bovine tendons (tECM) by urea extraction, which exhibited strong, pro-tenogenic bioactivity on human adipose-derived stem cells (hASCs). In this study, to advance our previous findings and gain insights into the biochemical nature of its pro-tenogenesis activity, tECM was fractionated using (i) an enzymatic digestion approach (pepsin, hyaluronidase, and chondroitinase) to yield various enzyme-digested tECM fractions; and (ii) a gelation-based approach to yield collagen matrix-enriched (CM) and non-collagenous matrix-enriched (NCM) fractions. Their tenogenic bioactivity on hASCs was assessed. Our results collectively indicated that non-collagenous tECM proteins, rather than collagens, are likely the important biochemical factors responsible for tECM pro-tenogenesis bioactivity. Mechanistically, RNA-seq analysis revealed that tECM and its non-collagenous portion induced similar transcriptional profiles of hASCs, particularly genes associated with cell proliferation, collagen synthesis, and tenogenic differentiation, which were distinct from transcriptome induced by its collagenous portion. From an application perspective, the enhanced solubility of the non-collagenous tECM, compared to tECM, should facilitate its combination with various water-soluble biomaterials for tissue engineering protocols. Our work provides insight into the molecular characterization of native tendon ECM, which will help to effectively translate their functional components into the design of well-defined, ECM biomaterials for tendon regeneration. STATEMENT OF SIGNIFICANCE: Significant progress has been made in extracellular matrix (ECM)-based biomaterials for tendon repair. However, their effectiveness remains debated, with conflicting research and clinical findings. Understanding the functional composition and mechanisms of action of ECM is crucial for developing safe and effective bioengineered scaffolds. Expanding on our previous work with bovine tendon ECM extracts (tECM) exhibiting strong pro-tenogenesis activity, we fractionated tECM to evaluate its bioactive moieties. Our findings indicate that the non-collagenous matrix within tECM, rather than the collagenous portions, plays a major role in the pro-tenogenesis bioactivity on human adipose-derived stem cells. These insights will drive further optimization of ECM-based biomaterials, including our advanced method for preparing highly soluble, non-collagenous matrix-enriched tendon ECM for effective tendon repair.


Assuntos
Colágeno , Matriz Extracelular , Animais , Bovinos , Humanos , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Tendões , Adipócitos , Engenharia Tecidual/métodos , Diferenciação Celular , Materiais Biocompatíveis/farmacologia , Alicerces Teciduais/química
17.
J Am Chem Soc ; 135(9): 3407-10, 2013 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-23425336

RESUMO

The new N,C-chelate boron compounds B(2-phenylazolyl)Mes2 [Mes = mesityl; azolyl = benzothiazolyl (1a), 4-methylthiazolyl (2a), benzoxazolyl (3a), benzimidazolyl (4a)] undergo an unprecedented multistructural transformation upon light irradiation or heating, sequentially producing isomers b, c, d, and e. The dark isomers b generated by photoisomerization of a undergo a rare thermal intramolecular H-atom transfer (HAT), reducing the azole ring and generating new isomers c, which are further transformed into isomers d. Remarkably, isomers d can be converted to their diastereomers e quantitatively by heating, and e can be converted back to d by irradiation at 300 nm. The structures of isomers 1d and 1e were established by X-ray diffraction. The unusual HAT reactivity can be attributed to the geometry of the highly energetic isomers b and the relatively low aromaticity of the azole rings. The boryl unit plays a key role in the reversible interconversion of d and e, as shown by mechanistic pathways established through DFT and TD-DFT calculations.


Assuntos
Azóis/síntese química , Compostos de Boro/síntese química , Quelantes/síntese química , Temperatura , Azóis/química , Compostos de Boro/química , Quelantes/química , Cristalografia por Raios X , Modelos Moleculares , Estrutura Molecular , Processos Fotoquímicos , Teoria Quântica
18.
Biochem Biophys Res Commun ; 431(3): 610-6, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23291181

RESUMO

The functions of miR-9 in some cancers are recently implicated in regulating proliferation, epithelial-mesenchymal transition (EMT), invasion and metastasis, apoptosis, and tumor angiogenesis, etc. miR-9 is commonly down-regulated in nasopharyngeal carcinoma (NPC), but the exact roles of miR-9 dysregulation in the pathogenesis of NPC remains unclear. Therefore, we firstly used miR-9-expressing CNE2 cells to determine the effects of miR-9 overexpression on global gene expression profile by microarray analysis. Microarray-based gene expression data unexpectedly demonstrated a significant number of up- or down-regulated immune- and inflammation-related genes, including many well-known interferon (IFN)-induced genes (e.g., IFI44L, PSMB8, IRF5, PSMB10, IFI27, PSB9_HUMAN, IFIT2, TRAIL, IFIT1, PSB8_HUMAN, IRF1, B2M and GBP1), major histocompatibility complex (MHC) class I molecules (e.g., HLA-B, HLA-C, HLA-F and HLA-H) and interleukin (IL)-related genes (e.g., IL20RB, GALT, IL7, IL1B, IL11, IL1F8, IL1A, IL6 and IL7R), which was confirmed by qRT-PCR. Moreover, the overexpression of miR-9 with the miRNA mimics significantly up- or down-regulated the expression of above-mentioned IFN-inducible genes, MHC class I molecules and IL-related genes; on the contrary, miR-9 inhibition by anti-miR-9 inhibitor in CNE2 and 5-8F cells correspondingly decreased or increased the aforementioned immune- and inflammation-related genes. Taken together, these findings demonstrate, for the first time, that miR-9 can modulate the expression of IFN-induced genes and MHC class I molecules in human cancer cells, suggesting a novel role of miR-9 in linking inflammation and cancer, which remains to be fully characterized.


Assuntos
Regulação Neoplásica da Expressão Gênica , Genes MHC Classe I , Interferons/metabolismo , MicroRNAs/fisiologia , Neoplasias Nasofaríngeas/genética , Carcinoma , Humanos , Inflamação/genética , Inflamação/imunologia , MicroRNAs/genética , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/imunologia , Análise de Sequência com Séries de Oligonucleotídeos
20.
J Plant Physiol ; 281: 153916, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36645936

RESUMO

Saline-alkaline soil affects crop growth and development, thereby suppressing the yields. Human activities and climate changes are putting arable land under the threat of saline-alkalization. To feed a growing global population in limited arable land, it is of great urgence to breed saline-alkaline tolerant crops to cope with food security. Plant salt-tolerance mechanisms have already been explored for decades. However, to date, the molecular mechanisms underlying plants responses to saline-alkaline stress have remained largely elusive. Here, we summarize recent advances in plant response to saline-alkaline stress and propose some points deserving of further exploration.


Assuntos
Tolerância ao Sal , Solo , Humanos , Tolerância ao Sal/fisiologia , Produtos Agrícolas/fisiologia
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