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1.
Org Lett ; 26(17): 3493-3497, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38506470

RESUMO

The morpholine heterocycle is a structural unit found in many bioactive compounds and FDA-approved drugs, but the generation of more complex C-functionalized morpholine derivatives remains considerably underexplored. Using systematic chemical diversity (SCD), a concept that guides the expansion of saturated drug-like scaffolds through regiochemical and stereochemical variation, we describe the synthesis of a collection of methyl-substituted morpholine acetic acid esters starting from enantiomerically pure amino acids and amino alcohols. In total, 24 diverse substituted morpholines were produced that vary systematically in regiochemistry and stereochemistry (relative and absolute). These diverse C-substituted morpholines can be directly applied in fragment screening or incorporated as building blocks in medicinal chemistry and library synthesis.


Assuntos
Morfolinas , Morfolinas/química , Estrutura Molecular , Estereoisomerismo , Ésteres/química , Aminoácidos/química , Aminoácidos/síntese química , Química Farmacêutica
2.
Sci Rep ; 13(1): 9738, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37322106

RESUMO

Calcium silicate-based materials are used to block the communication between the root canal and the periodontal ligament space. This brings the materials into contact with tissues and the potential for local and systemic elemental release and movement. The aim of the study was to evaluate the elemental release of bismuth from ProRoot MTA in contact with connective tissues after 30 and 180 days as well as any accumulation in peripheral organs using an animal model. Tricalcium silicate and hydroxyapatite containing 20% bismuth oxide (HAp-Bi) were used as controls. The null hypothesis was that bismuth migrates from tricalcium silicate-based materials when associated with silicon. The materials were examined using scanning electron microscopy, energy dispersive spectroscopy (SEM/EDS) and X-ray diffraction prior to implantation as well as using SEM/EDS, micro X-ray fluorescence and Raman spectroscopy after implantation to assess elemental presence in surrounding tissues. Histological analysis was used to evaluate the changes in tissue architecture and inductively coupled plasma mass spectrometry (ICP-MS) was used to investigate the elemental deposition. For the systemic investigation, routine blood analysis was performed and organs were obtained to evaluate the presence of bismuth and silicon using ICP-MS after acid digestion. In the histological analysis of the implantation sites, macrophages and multinucleated giant cells could be observed after 30 days which after 180 days became a chronic infiltrate; although, no major differences were identified in red and white blood cell analyses and biochemical tests. Implantation altered the materials as observed in the Raman analysis and bismuth was detected both locally and within kidney samples after both periods of analysis, indicating the potential for accumulation of bismuth in this organ. Smaller amounts of bismuth than observed in the kidney were also detected in blood, liver and brain for the ProRoot MTA and HAp-Bi after 180 days. Bismuth was released from the ProRoot MTA locally and was detected systemically and in samples without silicon; thus, the null hypothesis was rejected. The bismuth release demonstrated that this element accumulated both locally and systemically, mainly in the kidneys in comparison with brain and liver regardless of the material base.


Assuntos
Óxidos , Silício , Ratos , Animais , Óxidos/química , Ratos Wistar , Bismuto/química , Teste de Materiais , Compostos de Cálcio/química , Silicatos/química , Combinação de Medicamentos , Compostos de Alumínio/química , Microscopia Eletrônica de Varredura
3.
Eur J Pharm Sci ; 181: 106358, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36513193

RESUMO

Duloxetine (DLX) is widely used to treat major depressive disorder. Little is known about the mechanistic basis for DLX-related adverse effects (e.g., liver injury). Human CYP1A2 and CYP2D6 mainly contributes to DLX metabolism, which was proposed to be involved in its adverse effects. Here, we investigated the roles of Cyp1a2 and Cyp2d on DLX pharmacokinetic profile and tissue distribution using a Cyp1a2 knockout (Cyp1a2-KO) mouse model together with a Cyp2d inhibitor (propranolol). Cyp1a2-KO has the few effects on the systematic exposure (area under the plasma concentration-time curve, AUC) and tissue disposition of DLX and its primary metabolites. Propranolol dramatically increased the AUCs of DLX by 3 folds and 1.5 folds in WT and Cyp1a2-KO mice, respectively. Meanwhile, Cyp2d inhibitor decreased the AUC of Cyp2d-involved DLX metabolites (e.g., M16). Mouse tissue distribution revealed that DLX and its major metabolites were the most abundant in kidney, followed by liver and lung with/without Cyp2d inhibitor. Cyp2d inhibitor significantly increased DLX levels in tissues (e.g., liver) in WT and KO mice and decreases the levels of M3, M15, M16 and M17, while it increased the levels of M4, M28 and M29 in tissues. Our findings indicated that Cyp2d play a fundamental role on DLX pharmacokinetic profile and tissue distribution in mice. Clinical studies suggested that CYP1A2 has more effects on DLX systemic exposure than CYP2D6. Further studies in liver humanized mice or clinical studies concerning CYP2D6 inhibitors-DLX interaction study could clarify the roles of CYP2D6 on DLX pharmacokinetics and toxicity in human.


Assuntos
Transtorno Depressivo Maior , Inibidores da Recaptação de Serotonina e Norepinefrina , Humanos , Camundongos , Animais , Cloridrato de Duloxetina , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP2D6/metabolismo , Propranolol , Serotonina , Fármacos do Sistema Nervoso Central , Camundongos Knockout
4.
Sci Rep ; 12(1): 7100, 2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35501338

RESUMO

Regulatory testing of hydraulic cements used in dentistry and standard test methods for root-end filling materials do not exist. The aim of this study was to identify a simple, reproducible method for testing the solubility of materials that set with water (hydraulic) used as root-end filling materials in dentistry. Commercial and prototype hydraulic cements were characterized by scanning electron microscopy and X-ray diffraction analyses and their solubilities were determined using ISO 6876; 2012 standard, a modified ISO 6876 method with media alternative to water and a new method measuring the percentage mass loss and volume change of materials (micro-CT method) from a single surface exposed to three solutions. The solubility testing was performed by three operators to enable an intra-laboratory comparison. The solubility data obtained from the two commercial and two prototype materials varied depending on the method used, with the ISO 6876 method identifying differences in solubility of the materials (p < 0.05) but when modified with alternative solutions, no differences were found (p > 0.05). The changes in solution thus effected the solubility of the tested materials. Inter-operator differences were observed with the weight changes determined from the new method indicating this method was not robust. The weight and volume assessments using the new method were not solution-dependent. The advantage of the proposed method compared with the ISO standard is its simplicity, enabling a number of tests to be performed on the same set of samples that also more closely mimics the clinical environment.


Assuntos
Materiais Restauradores do Canal Radicular , Compostos de Cálcio , Silicatos , Solubilidade , Água
5.
Eur J Med Chem ; 219: 113402, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-33845234

RESUMO

A collection of potent antimicrobials consisting of novel 1,3-bis-benzoic acid and trifluoromethyl phenyl derived pyrazoles has been synthesized and tested for antibacterial activity. The majority of trifluoromethyl phenyl derivatives are highly potent growth inhibitors of Gram-positive bacteria and showed low toxicity to human cultured cells. In particular, two compounds (59 and 74) were selected for additional studies. These compounds are highly effective against Staphylococcus aureus as shown by a low minimum inhibitory concentration (MIC), a bactericidal effect in time-kill assays, moderate inhibition of biofilm formation as well as biofilm destruction, and a bactericidal effect against stationary phase cells representing non-growing persister cells. Multistep resistance assays showed a very low tendency for S. aureus and Enterococcus faecalis to develop resistance through mutation. Additionally, in vivo mouse model studies showed no harmful effects at doses up to 50 mg/kg using 14 blood plasma organ toxicity markers or TUNEL assay in liver and kidney. Investigations into the mode of action by performing macromolecular synthesis inhibition studies showed a broad range of inhibitory effects, suggesting targets that have a global effect on bacterial cell function.


Assuntos
Compostos de Anilina/química , Antibacterianos/farmacologia , Bactérias Gram-Positivas/efeitos dos fármacos , Pirazóis/química , Compostos de Anilina/síntese química , Compostos de Anilina/farmacologia , Antibacterianos/química , Biofilmes/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/isolamento & purificação , Enterococcus faecalis/fisiologia , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/fisiologia , Relação Estrutura-Atividade
7.
Rev Sci Instrum ; 91(4): 043508, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32357683

RESUMO

A line VISAR (Velocity Interferometer System for Any Reflector) has been designed and commissioned at the Sandia National Laboratory's Z-machine. The instrument consists of an F/2 collection system, beam transport, and an interferometer table that contains two Mach-Zehnder type interferometers and an eight channel Gated Optical Imaging (GOI) system. The VISAR probe laser operates at the 532 nm wavelength, and the GOI bandpass is 540-600 nm. The output of each interferometer is passed to an optical streak camera with four selectable sweep speeds. The system is designed with three interchangeable optics modules to select a full field of view of 1 mm, 2 mm, or 4 mm. The optical beam transport system connects the target image plane to the interferometers and the gated optical imagers. The target is integrated into a sacrificial final optics assembly that is integral to the transport beamline.

8.
Trends Pharmacol Sci ; 40(9): 608-612, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31280901

RESUMO

It has been a widely held notion within the biomedical research community that the reliable modulation of transcription factors with small molecules would represent a holy grail, given their role in directly potentiating oncogenic programs. Among the transcription factors that have been held in highest regard is Myc, since its dysregulation is among the most recurrent events in human cancer. Despite intense efforts, the ability to identify compounds that bind directly to Myc, resulting in its functional inhibition, have been met with only moderate success. However, a new approach reported by Struntz et al. (Cell Chem. Biol., 2019) focuses on a different strategy of discovering molecules that bind to Myc's obligate partner Max. Using a small-molecule microarray screen, they report the identification of KI-MS2-008, a compound that results in the stabilization of Max homodimers and the attenuation of Myc. KI-MS2-008 suppresses cancer cell grown both in vitro and within in vivo models.


Assuntos
Neoplasias , Proteínas Proto-Oncogênicas c-myc , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Carcinogênese , Humanos , Fatores de Transcrição
9.
JBMR Plus ; 2(1): 47-54, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30283889

RESUMO

Down syndrome (DS), characterized by trisomy of human chromosome 21, is associated with a variety of endocrine disorders as well as profound skeletal abnormalities. The low bone mass phenotype in DS is defined by low bone turnover due to decreased osteoclast and osteoblast activity, decreasing the utility of antiresorptive agents in people with DS. Sclerostin antibody (SclAb) is a therapeutic candidate currently being evaluated as a bone anabolic agent. Scl, the product of the sclerostin gene (SOST), inhibits bone formation through its inhibition of Wnt signaling. SclAb increases bone mass by suppressing the action of the endogenous inhibitor of bone formation, Scl. To examine the effects of SclAb on the DS bone phenotype, 8-week-old male wild-type (WT) andTs65Dn DS mice were treated with 4 weekly iv injections of 100 mg/kg SclAb. Dual-energy X-ray absorptiometry (DXA), microCT, and dynamic histomorphometry analyses revealed that SclAb had a significant anabolic effect on both age-matched WT littermate controls and Ts65Dn DS mice that was osteoblast mediated, without significant changes in osteoclast parameters. SclAb treatment significantly increased both cortical and trabecular bone mass at multiple sites; SclAb treatment resulted in the normalization of Ts65Dn bone mineral density (BMD) to WT levels in the proximal tibia, distal femur, and whole body. Ex vivo bone marrow cultures demonstrated that SclAb increased the recruitment of the mesenchymal progenitors into the osteoblast lineage, as indicated by increased alkaline phosphatase-positive colonies, with no effect on osteoclast differentiation. Together, in the setting of a murine model of DS and decreased bone turnover, SclAb had a potent anabolic effect. SclAb stimulated bone formation and increased osteoblastogenesis without affecting osteoclastogenesis or bone resorption. These data suggest that SclAb is a promising new therapy to improve bone mass and reduce fracture risk in the face of the low bone mass and turnover prevalent in the DS population.

10.
J Microsc ; 271(3): 345-354, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29999527

RESUMO

Cell counting is commonly used to determine proliferation rates in cell cultures and for adherent cells it is often a 'destructive' process requiring disruption of the cell monolayer resulting in the inability to follow cell growth longitudinally. This process is time consuming and utilises significant resource. In this study a relatively inexpensive, rapid and widely applicable phase contrast microscopy-based technique has been developed that emulates the contrast changes taking place when bright field microscope images of epithelial cell cultures are defocused. Processing of the resulting images produces an image that can be segmented using a global threshold; the number of cells is then deduced from the number of segmented regions and these cell counts can be used to generate growth curves. The parameters of this method were tuned using the discrete mereotopological relations between ground truth and processed images. Cell count accuracy was improved using linear discriminant analysis to identify spurious noise regions for removal. The proposed cell counting technique was validated by comparing the results with a manual count of cells in images, and subsequently applied to generate growth curves for oral keratinocyte cultures supplemented with a range of concentrations of foetal calf serum. The approach developed has broad applicability and utility for researchers with standard laboratory imaging equipment.


Assuntos
Automação Laboratorial/métodos , Contagem de Células/métodos , Células Epiteliais/citologia , Microscopia de Contraste de Fase , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Processamento de Imagem Assistida por Computador/métodos
11.
J Periodontal Res ; 53(4): 565-574, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29704258

RESUMO

BACKGROUND AND OBJECTIVE: Epithelial-mesenchymal transition (EMT) is a process by which epithelial cells acquire a mesenchymal-like phenotype and this may be induced by exposure to gram-negative bacteria. It has been proposed that EMT is responsible for compromising epithelial barrier function in the pathogenesis of several diseases. However, the possible role of EMT in the pathogenesis of periodontitis has not previously been investigated. The aim of this study therefore was to investigate whether gram-negative, anaerobic periodontal pathogens could trigger EMT in primary oral keratinocytes in vitro. MATERIAL AND METHODS: Primary oral keratinocytes were harvested from labial mandibular mucosa of Wistar Han rats. Cells were exposed to heat-killed Fusobacterium nucleatum and Porphyromonas gingivalis (100 bacteria/epithelial cell) and to 20 µg/mL of Escherichia coli lipopolysaccharide over an 8-day period. Exposure to bacteria did not significantly change epithelial cell number or vitality in comparison with unstimulated controls at the majority of time-points examined. Expression of EMT marker genes was determined by semiquantitative RT-PCR at 1, 5, and 8 days following stimulation. The expression of EMT markers was also assessed by immunofluorescence (E-cadherin and vimentin) and using immunocytochemistry to determine Snail activation. The loss of epithelial monolayer coherence, in response to bacterial challenge, was determined by measuring trans-epithelial electrical resistance. The induction of a migratory phenotype was investigated using scratch-wound and transwell migration assays. RESULTS: Exposure of primary epithelial cell cultures to periodontal pathogens was associated with a significant decrease in transcription (~3-fold) of E-cadherin and the upregulation of N-cadherin, vimentin, Snail, matrix metalloproteinase-2 (~3-5 fold) and toll-like receptor 4. Bacterial stimulation (for 8 days) also resulted in an increased percentage of vimentin-positive cells (an increase of 20% after stimulation with P. gingivalis and an increase of 30% after stimulation with F. nucleatum, compared with controls). Furthermore, periodontal pathogens significantly increased the activation of Snail (60%) and cultures exhibited a decrease in electrical impedance (P < .001) in comparison with unexposed controls. The migratory ability of the cells increased significantly in response to bacterial stimulation, as shown by both the number of migrated cells and scratch-wound closure rates. CONCLUSION: Prolonged exposure of primary rat oral keratinocyte cultures to periodontal pathogens generated EMT-like features, which introduces the possibility that this process may be involved in loss of epithelial integrity during periodontitis.


Assuntos
Transição Epitelial-Mesenquimal , Fusobacterium nucleatum/patogenicidade , Periodontite/microbiologia , Porphyromonas gingivalis/patogenicidade , Animais , Caderinas/metabolismo , Impedância Elétrica , Células Epiteliais/microbiologia , Imunofluorescência , Imuno-Histoquímica , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Fenótipo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Transcrição da Família Snail/metabolismo , Vimentina/metabolismo
12.
Cell Adh Migr ; 12(2): 127-137, 2018 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-28873015

RESUMO

Epithelial-mesenchymal transition (EMT) is potentially involved in increasing metastasis of oral squamous cell carcinoma (OSCC). Periodontal pathogens are well-known for their ability to induce intense immune responses and here we investigated whether they are involved in inducing EMT. Cultures of OSCC cell line (H400) were treated separately with heat-killed periodontal pathogens F. nucleatum, or P. gingivalis or E. coli LPS for 8 d. EMT-associated features were assayed using sq-PCR and PCR-arrays, for EMT-related markers, and ELISAs for TGF-ß1, TNF-α, and EGF. The migratory ability of cells was investigated using scratch and transwell migration assays. E-cadherin and vimentin expression was assessed using immunofluorescence while Snail activation was detected with immunocytochemistry. In addition, the integrity of the cultured epithelial layer was investigated using transepithelial electrical resistance (TEER). PCR data showed significant upregulation after 1, 5, and 8 d in transcription of mesenchymal markers and downregulation of epithelial ones compared with unstimulated controls, which were confirmed by immunofluorescence. Periodontal pathogens also caused a significant increase in level of all cytokines investigated which could be involved in EMT-induction and Snail activation. Exposure of cells to the bacteria increased migration and the rate of wound closure. Downregulation of epithelial markers also resulted in a significant decrease in impedance resistance of cell monolayers to passage of electrical current. These results suggested that EMT was likely induced in OSCC cells in response to stimulation by periodontal pathogens.


Assuntos
Carcinoma de Células Escamosas/microbiologia , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal/fisiologia , Escherichia coli/patogenicidade , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Células Epiteliais/microbiologia , Humanos , Fatores de Transcrição da Família Snail/metabolismo , Fatores de Transcrição/metabolismo , Vimentina/metabolismo
13.
J Orthop Res ; 35(1): 183-192, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-26990453

RESUMO

Current convex tethering techniques for treatment of scoliosis have centered on anterior convex staples or polypropylene tethers. We hypothesized that an allograft tendon tether inserted via the costo-transverse foramen would correct an established spinal deformity. In the pilot study, six 8-week-old pigs underwent allograft tendon tethering via the costo-transverse foreman or sham to test the strength of the transplanted tendon to retard spine growth. After 4 months, spinal deformity in three planes was induced in all animals with allograft tendons. In the treatment study, the allograft tendon tether was used to treat established scoliosis in 11 8-week-old pigs (spinal deformity > 50°). Once the deformity was observed (4 months) animals were assigned to either no treatment group or allograft tendon tether group and progression assessed by monthly radiographs. At final follow-up, coronal Cobb angle and maximum vertebral axial rotation of the treatment group was significantly smaller than the non-treatment group, whereas sagittal kyphosis of the treatment group was significantly larger than the non-treatment group. In sum, a significant correction was achieved using a unilateral allograft tendon spinal tether, suggesting that an allograft tendon tethering approach may represent a novel fusion-less procedure to correct idiopathic scoliosis. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:183-192, 2017.


Assuntos
Escoliose/cirurgia , Tendões/transplante , Aloenxertos , Animais , Projetos Piloto , Suínos
15.
Transl Psychiatry ; 6: e748, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26926884

RESUMO

An extensive literature links circadian irregularities and/or sleep abnormalities to mood disorders. Despite the strong genetic component underlying many mood disorders, however, previous genetic associations between circadian clock gene variants and major depressive disorder (MDD) have been weak. We applied a combined molecular/functional and genetic association approach to circadian gene polymorphisms in sex-stratified populations of control subjects and case subjects suffering from MDD. This approach identified significant sex-dependent associations of common variants of the circadian clock genes hClock, hPer3 and hNpas2 with major depression and demonstrated functional effects of these polymorphisms on the expression or activity of the hCLOCK and hPER3 proteins, respectively. In addition, hCLOCK expression is affected by glucocorticoids, consistent with the sex-dependency of the genetic associations and the modulation of glucocorticoid-mediated stress response, providing a mechanism by which the circadian clock controls outputs that may affect psychiatric disorders. We conclude that genetic polymorphisms in circadian genes (especially hClock and hPer3, where functional assays could be tested) influence risk of developing depression in a sex- and stress-dependent manner. These studies support a genetic connection between circadian disruption and mood disorders, and confirm a key connection between circadian gene variation and major depression.


Assuntos
Relógios Circadianos/fisiologia , Ritmo Circadiano/fisiologia , Transtorno Depressivo Maior/fisiopatologia , Variação Genética/fisiologia , Relógios Circadianos/genética , Ritmo Circadiano/genética , Transtorno Depressivo Maior/genética , Feminino , Variação Genética/genética , Humanos , Masculino , Fatores Sexuais
16.
Acta Psychiatr Scand ; 133(2): 144-153, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26114830

RESUMO

OBJECTIVE: Examine the effects of obesity and metabolic syndrome on outcome in bipolar disorder. METHOD: The Comparative Effectiveness of a Second Generation Antipsychotic Mood Stabilizer and a Classic Mood Stabilizer for Bipolar Disorder (Bipolar CHOICE) study randomized 482 participants with bipolar disorder in a 6-month trial comparing lithium- and quetiapine-based treatment. Baseline variables were compared between groups with and without obesity, with and without abdominal obesity, and with and without metabolic syndrome respectively. The effects of baseline obesity, abdominal obesity, and metabolic syndrome on outcomes were examined using mixed effects linear regression models. RESULTS: At baseline, 44.4% of participants had obesity, 48.0% had abdominal obesity, and 27.3% had metabolic syndrome; neither obesity, nor abdominal obesity, nor metabolic syndrome were associated with increased global severity, mood symptoms, or suicidality, or with poorer functioning or life satisfaction. Treatment groups did not differ on prevalence of obesity, abdominal obesity, or metabolic syndrome. By contrast, among the entire cohort, obesity was associated with less global improvement and less improvement in total mood and depressive symptoms, suicidality, functioning, and life satisfaction after 6 months of treatment. Abdominal obesity was associated with similar findings. Metabolic syndrome had no effect on outcome. CONCLUSION: Obesity and abdominal obesity, but not metabolic syndrome, were associated with less improvement after 6 months of lithium- or quetiapine-based treatment.

17.
J Dent Res ; 94(11): 1552-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26272646

RESUMO

There is emerging recognition of the importance of a physiologically relevant in vitro cell culture environment to promote maintenance of stem cells for tissue engineering and regenerative medicine purposes. In vivo, appropriate cellular cues are provided by local tissue extracellular matrix (ECM), and these are not currently recapitulated well in vitro using traditional cultureware. We therefore hypothesized that better replication of the in vivo environment for cell culture and differentiation could be achieved by culturing dental pulp cells with their associated ECM. Primary dental pulp cells were subsequently seeded onto pulp-derived ECM-coated cultureware. While at up to 24 h they exhibited the same level of adherence as those cells seeded on tissue culture-treated surfaces, by 4 d cell numbers and proliferation rates were significantly decreased in cells grown on pulp ECM compared with controls. Analysis of stem cell and differentiation marker transcripts, as well as Oct 3/4 protein distribution, supported the hypothesis that cells cultured on ECM better maintained a stem cell phenotype compared with those cultured on standard tissue culture-treated surfaces. Subsequent differentiation analysis of cells cultured on ECM demonstrated that they exhibited enhanced mineralization, as determined by alizarin red staining and mineralized marker expression. Supplementation of a 3% alginate hydrogel with pulp ECM components and dental pulp cells followed by differentiation induction in mineralization medium resulted in a time-dependent mineral deposition at the periphery of the construct, as demonstrated histologically and using micro-computed tomography analysis, which was reminiscent of tooth structure. In conclusion, data indicate that culture of pulp cells in the presence of ECM better replicates the in vivo environment, maintaining a stem cell phenotype suitable for downstream tissue engineering applications.


Assuntos
Biomimética/métodos , Polpa Dentária/citologia , Animais , Materiais Biomiméticos/uso terapêutico , Bovinos , Diferenciação Celular/fisiologia , Células Cultivadas , Polpa Dentária/fisiologia , Matriz Extracelular/fisiologia , Perfilação da Expressão Gênica , Masculino , Microscopia Eletrônica de Varredura , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células-Tronco/citologia , Células-Tronco/fisiologia , Técnicas de Cultura de Tecidos , Microtomografia por Raio-X
18.
Transl Psychiatry ; 5: e523, 2015 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-25756806

RESUMO

Major depressive disorder (MDD) is increasingly viewed as interplay of environmental stressors and genetic predisposition, and recent data suggest that the disease affects not only the brain, but the entire body. As a result, we aimed at determining whether patients with major depression have aberrant molecular responses to stress in peripheral tissues. We examined the effects of two metabolic stressors, galactose (GAL) or reduced lipids (RL), on the transcriptome and miRNome of human fibroblasts from 16 pairs of patients with MDD and matched healthy controls (CNTR). Our results demonstrate that both MDD and CNTR fibroblasts had a robust molecular response to GAL and RL challenges. Most importantly, a significant part (messenger RNAs (mRNAs): 26-33%; microRNAs (miRNAs): 81-90%) of the molecular response was only observed in MDD, but not in CNTR fibroblasts. The applied metabolic challenges uncovered mRNA and miRNA signatures, identifying responses to each stressor characteristic for the MDD fibroblasts. The distinct responses of MDD fibroblasts to GAL and RL revealed an aberrant engagement of molecular pathways, such as apoptosis, regulation of cell cycle, cell migration, metabolic control and energy production. In conclusion, the metabolic challenges evoked by GAL or RL in dermal fibroblasts exposed adaptive dysfunctions on mRNA and miRNA levels that are characteristic for MDD. This finding underscores the need to challenge biological systems to bring out disease-specific deficits, which otherwise might remain hidden under resting conditions.


Assuntos
Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/metabolismo , Fibroblastos/metabolismo , Estresse Fisiológico/genética , Transcriptoma/genética , Adulto , Feminino , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , RNA Mensageiro/genética , Pele/metabolismo , Adulto Jovem
19.
J Bone Miner Metab ; 33(4): 371-82, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24997523

RESUMO

Stem-cell-based therapies provide a biological basis for the regeneration of mineralised tissues. Stem cells isolated from adipose tissue (ADSCs), bone marrow (BMSCs) and dental pulp (DPSCs) have the capacity to form mineralised tissue. However, studies comparing the capacity of ADSCs with BMSCs and DPSCs for mineralised tissue engineering are lacking, and their ability to regenerate dental tissues has not been fully explored. Characterisation of the cells using fluorescence-activated cell sorting and semi-quantitative reverse transcription PCR for MSC markers indicated that they were immunophenotypically similar. Alizarin red (AR) staining and micro-computed tomography (µCT) analyses demonstrated that the osteogenic potential of DPSCs was significantly greater than that of BMSCs and ADSCs. Scanning electron microscopy and AR staining showed that the pattern of mineralisation in DPSC cultures differed from ADSCs and BMSCs, with DPSC cultures lacking defined mineralised nodules and instead forming a diffuse layer of low-density mineral. Dentine matrix components (DMCs) were used to promote dentinogenic differentiation. Their addition to cultures resulted in increased amounts of mineral deposited in all three cultures and significantly increased the density of mineral deposited in BMSC cultures, as determined by µCT analysis. Addition of DMCs also increased the relative gene expression levels of the dentinogenic markers dentine sialophosphoprotein and dentine matrix protein 1 in ADSC and BMSC cultures. In conclusion, DPSCs show the greatest potential to produce a comparatively high volume of mineralised matrix; however, both dentinogenesis and mineral volume was enhanced in ADSC and BMSC cultures by DMCs, suggesting that these cells show promise for regenerative dental therapies.


Assuntos
Tecido Adiposo/citologia , Células da Medula Óssea/citologia , Polpa Dentária/citologia , Dentinogênese/fisiologia , Células-Tronco Mesenquimais/citologia , Adipogenia , Animais , Técnicas de Cultura de Células , Diferenciação Celular , Proliferação de Células , Separação Celular , Células Cultivadas , Proteínas da Matriz Extracelular/química , Citometria de Fluxo , Regulação da Expressão Gênica , Masculino , Fenótipo , Fosfoproteínas/química , Ratos , Ratos Wistar , Medicina Regenerativa , Sialoglicoproteínas/química
20.
Cryobiology ; 69(2): 342-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25127874

RESUMO

The effects of cryopreservation on mesenchymal stem cell (MSC) phenotype are not well documented; however this process is of increasing importance for regenerative therapies. This study examined the effect of cryopreservation (10% dimethyl-sulfoxide) on the morphology, viability, gene-expression and relative proportion of MSC surface-markers on cells derived from rat adipose, bone marrow and dental pulp. Cryopreservation significantly reduced the number of viable cells in bone marrow and dental pulp cell populations but had no observable effect on adipose cells. Flow cytometry analysis demonstrated significant increases in the relative expression of MSC surface-markers, CD90 and CD29/CD90 following cryopreservation. sqRT-PCR analysis of MSC gene-expression demonstrated increases in pluripotent markers for adipose and dental pulp, together with significant tissue-specific increases in CD44, CD73-CD105 following cryopreservation. Cells isolated from different tissue sources did not respond equally to cryopreservation with adipose tissue representing a more robust source of MSCs.


Assuntos
Tecido Adiposo/citologia , Células da Medula Óssea/citologia , Criopreservação , Polpa Dentária/citologia , Células-Tronco Mesenquimais/citologia , Animais , Antígenos CD/análise , Separação Celular , Sobrevivência Celular , Masculino , Ratos , Ratos Wistar
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