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1.
Am J Stem Cells ; 12(4): 92-97, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38021456

RESUMO

Osteonecrosis of the femoral head (ONFH) is a debilitating condition that predominantly affects young individuals, resulting in disability and involving significant healthcare costs. Therefore, it is crucial to develop an effective therapeutic strategy to treat this debilitating disease. In this context, autologous bone marrow-derived mesenchymal stem cells (auto-BM-MSCs) have emerged as a promising approach for treating ONFH. In this case report, we applied this therapy to a patient with ONFH and evaluated both its safety and therapeutic benefits. The treatment consisted of the administration of a single dose of 4×107 ex vivo-expanded auto-BM-MSCs combined with biomolecules derived from platelet-rich plasma. These therapeutic agents were injected into the necrotic zone after accessing it through the technique of multiple small drillings. Subsequently, the progression of ONFH was assessed after 18 months of the auto-BM-MSC administration. Radiographic evaluation showed that the initial femoral head flattening persisted, but no further progression or coxofemoral arthritic changes were observed. Nevertheless, magnetic resonance imaging (MRI) demonstrated a significant improvement in the affected femoral head's area, resulting in a Kerboull angle of 80°, without evidence of flattening or a notable collapse compared to the preoperative condition. Furthermore, the patient exhibited a remarkable functional improvement, as evidenced by a modified Harris hip score of 90 points. The absence of any additional surgery reinforces the positive outcomes achieved through this therapeutic intervention. In conclusion, our case study provides evidence for using the ex vivo-expanded auto-BM-MSCs in combination with platelet-rich plasma-derived biomolecules as a viable and safe treatment for ONFH. However, further research and clinical trials are necessary to validate these promising findings.

2.
Sci Rep ; 9(1): 793, 2019 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-30692599

RESUMO

Identifying diseases displaying chronic low plasma Coenzyme Q10 (CoQ) values may be important to prevent possible cardiovascular dysfunction. The aim of this study was to retrospectively evaluate plasma CoQ concentrations in a large cohort of pediatric and young adult patients. We evaluated plasma CoQ values in 597 individuals (age range 1 month to 43 years, average 11 years), studied during the period 2005-2016. Patients were classified into 6 different groups: control group of healthy participants, phenylketonuric patients (PKU), patients with mucopolysaccharidoses (MPS), patients with other inborn errors of metabolism (IEM), patients with neurogenetic diseases, and individuals with neurological diseases with no genetic diagnosis. Plasma total CoQ was measured by reverse-phase high-performance liquid chromatography with electrochemical detection and ultraviolet detection at 275 nm. ANOVA with Bonferroni correction showed that plasma CoQ values were significantly lower in the PKU and MPS groups than in controls and neurological patients. The IEM group showed intermediate values that were not significantly different from those of the controls. In PKU patients, the Chi-Square test showed a significant association between having low plasma CoQ values and being classic PKU patients. The percentage of neurogenetic and other neurological patients with low CoQ values was low (below 8%). In conclusión, plasma CoQ monitoring in selected groups of patients with different IEM (especially in PKU and MPS patients, but also in IEM under protein-restricted diets) seems advisable to prevent the possibility of a chronic blood CoQ suboptimal status in such groups of patients.


Assuntos
Erros Inatos do Metabolismo/genética , Mucopolissacaridoses/genética , Doenças do Sistema Nervoso/sangue , Fenilcetonúrias/genética , Ubiquinona/análogos & derivados , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Erros Inatos do Metabolismo/sangue , Mucopolissacaridoses/sangue , Mutação , Doenças do Sistema Nervoso/genética , Fenilcetonúrias/sangue , Estudos Retrospectivos , Análise de Sequência de DNA , Ubiquinona/sangue , Adulto Jovem
3.
J Mol Endocrinol ; 60(3): 247-259, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29438976

RESUMO

Glutamate dehydrogenase (Gdh) plays a central role in ammonia detoxification by catalysing reversible oxidative deamination of l-glutamate into α-ketoglutarate using NAD+ or NADP+ as cofactor. To gain insight into transcriptional regulation of glud, the gene that codes for Gdh, we isolated and characterised the 5' flanking region of glud from gilthead sea bream (Sparus aurata). In addition, tissue distribution, the effect of starvation as well as short- and long-term refeeding on Gdh mRNA levels in the liver of S. aurata were also addressed. 5'-Deletion analysis of glud promoter in transiently transfected HepG2 cells, electrophoretic mobility shift assays, chromatin immunoprecipitation (ChIP) and site-directed mutagenesis allowed us to identify upstream stimulatory factor 2 (Usf2) as a novel factor involved in the transcriptional regulation of glud Analysis of tissue distribution of Gdh and Usf2 mRNA levels by reverse transcriptase-coupled quantitative real-time PCR (RT-qPCR) showed that Gdh is mainly expressed in the liver of S. aurata, while Usf2 displayed ubiquitous distribution. RT-qPCR and ChIP assays revealed that long-term starvation down-regulated the hepatic expression of Gdh and Usf2 to similar levels and reduced Usf2 binding to glud promoter, while refeeding resulted in a slow but gradual restoration of both Gdh and Usf2 mRNA abundance. Herein, we demonstrate that Usf2 transactivates S. aurata glud by binding to an E-box located in the proximal region of glud promoter. In addition, our findings provide evidence for a new regulatory mechanism involving Usf2 as a key factor in the nutritional regulation of glud transcription in the fish liver.


Assuntos
Glutamato Desidrogenase/genética , Transcrição Gênica , Fatores Estimuladores Upstream/metabolismo , Região 5'-Flanqueadora/genética , Animais , Sequência de Bases , Elementos E-Box/genética , Glutamato Desidrogenase/metabolismo , Fígado/metabolismo , Mutação/genética , Regiões Promotoras Genéticas , Ligação Proteica/genética , Dourada/genética , Distribuição Tecidual/genética , Ativação Transcricional/genética , Fatores Estimuladores Upstream/genética
4.
Front Physiol ; 8: 170, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28386233

RESUMO

In vitro and ex vivo experiments indicate that elastase-2 (ELA-2), a chymotrypsin-serine protease elastase family member 2A, is an alternative pathway for angiotensin II (Ang II) generation. However, the role played by ELA-2 in vivo is unclear. We examined ELA-2 knockout (ELA-2KO) mice compared to wild-type (WT) mice and determined whether ELA-2 played a role in hemodynamics [arterial pressure (AP) and heart rate (HR)], cardiocirculatory sympathovagal balance and baroreflex sensitivity. The variability of systolic arterial pressure (SAP) and pulse interval (PI) for evaluating autonomic modulation was examined for time and frequency domains (spectral analysis), whereas a symbolic analysis was also used to evaluate PI variability. In addition, baroreflex sensitivity was examined using the sequence method. Cardiac function was evaluated echocardiographically under anesthesia. The AP was normal whereas the HR was reduced in ELA-2KO mice (425 ± 17 vs. 512 ± 13 bpm from WT). SAP variability and baroreflex sensitivity were similar in both strains. The LF power from the PI spectrum (33.6 ± 5 vs. 51.8 ± 4.8 nu from WT) and the LF/HF ratio (0.60 ± 0.1 vs. 1.45 ± 0.3 from WT) were reduced, whereas the HF power was increased (66.4 ± 5 vs. 48.2 ± 4.8 nu from WT) in ELA-2KO mice, indicating a shift toward parasympathetic modulation of HR. Echocardiographic examination showed normal fractional shortening and an ejection fraction in ELA-2KO mice; however, the cardiac output, stroke volume, and ventricular size were reduced. These findings provide the first evidence that ELA-2 acts on the sympathovagal balance of the heart, as expressed by the reduced sympathetic modulation of HR in ELA-2KO mice.

5.
PLoS One ; 10(8): e0134601, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26244896

RESUMO

The initiation or progression of periodontitis might involve a local renin-angiotensin system (RAS) in periodontal tissue. The aim of this study was to further characterize the local RAS in human and rat periodontal tissues between healthy and periodontally-affected tissue. Components of the RAS were investigated using in vitro, ex vivo and in vivo experiments involving both human and Wistar rat periodontium. Although not upregulated when challenged with P. gingivalis-lipopolysaccharide, human gingival and periodontal ligament fibroblasts expressed RAS components. Likewise, healthy and inflamed human gingiva expressed RAS components, some of which were shown to be functional, yet no differences in expression were found between healthy and diseased gingiva. However, in inflamed tissue the immunoreactivity was greater for the AT1R compared to AT2R in fibroblasts. When compared to healthy tissue, ACE activity was increased in human gingiva from volunteers with gingivitis. Human-gingiva homogenates generated Ang II, Ang 1-9 and Ang 1-7 when incubated with precursors. In gingiva homogenates, Ang II formation from Ang I was nearly abolished only when captopril and chymostatin were combined. Ang 1-7 formation was significantly greater when human gingiva homogenates were incubated with chymostatin alone compared to incubation without any inhibitor, only captopril, or captopril and chymostatin. In rat gingiva, RAS components were also found; their expression was not different between healthy and experimentally induced periodontitis (EP) groups. However, renin inhibition (aliskiren) and an AT1R antagonist (losartan) significantly blocked EP-alveolar-bone loss in rats. Collectively, these data are consistent with the hypothesis that a local RAS system is not only present but is also functional in both human and rat periodontal tissue. Furthermore, blocking AT1R and renin can significantly prevent periodontal bone loss induced by EP in rats.


Assuntos
Periodontite/imunologia , Periodontite/patologia , Periodonto/imunologia , Periodonto/patologia , Sistema Renina-Angiotensina , Adulto , Sequência de Aminoácidos , Angiotensina I/análise , Angiotensina I/imunologia , Angiotensina II/análise , Angiotensina II/imunologia , Animais , Células Cultivadas , Feminino , Gengiva/citologia , Gengiva/imunologia , Gengiva/patologia , Humanos , Inflamação/imunologia , Inflamação/patologia , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/análise , Fragmentos de Peptídeos/imunologia , Ratos Wistar , Receptores de Angiotensina/análise , Receptores de Angiotensina/imunologia , Renina/imunologia , Adulto Jovem
6.
Biochim Biophys Acta ; 1839(4): 288-96, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24418603

RESUMO

Alanine aminotransferase (ALT) provides a molecular link between carbohydrate and amino acid metabolism. In humans, two ALT isoforms have been characterized: ALT1, cytosolic, and ALT2, mitochondrial. To gain insight into the transcriptional regulation of the ALT2 gene, we cloned and characterized the human ALT2 promoter. 5'-deletion analysis of ALT2 promoter in transiently transfected HepG2 cells and site-directed mutagenesis allowed us to identify ATF4 as a new factor involved in the transcriptional regulation of ALT2 expression. Quantitative RT-PCR assays showed that the metabolic stressors histidinol and tunicamycin increased ATF4 levels and up-regulated ALT2 in HepG2 and Huh7 cells. Consistently, knock-down of ATF4 decreased ALT2 mRNA levels in HepG2 and Huh-7 cells. Moreover, ATF4 silencing prevented the activating effect of histidinol and tunicamycin on ATF4 and ALT2 expression. Our findings point to ALT2 as an enzyme involved in the metabolic adaptation of the cell to stress.


Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Alanina Transaminase/metabolismo , Aminoácidos/metabolismo , Estresse Fisiológico/genética , Fator 4 Ativador da Transcrição/antagonistas & inibidores , Fator 4 Ativador da Transcrição/genética , Aminoácidos/genética , Sequência de Bases , Metabolismo dos Carboidratos/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Células Hep G2 , Histidinol/farmacologia , Humanos , Mitocôndrias/genética , Regiões Promotoras Genéticas
7.
Mar Biotechnol (NY) ; 14(1): 46-62, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21607544

RESUMO

Alanine aminotransferase (ALT) plays an important role in amino acid metabolism and gluconeogenesis. The preference of carnivorous fish for protein amino acids instead of carbohydrates as a source of energy lead us to study the transcriptional regulation of the mitochondrial ALT (mALT) gene and to characterize the enzyme kinetics and modulation of mALT expression in the kidney of gilthead sea bream (Sparus aurata) under different nutritional and hormonal conditions. 5'-Deletion analysis of mALT promoter in transiently transfected HEK293 cells, site-directed mutagenesis and electrophoretic mobility shift assays allowed us to identify HNF4α as a new factor involved in the transcriptional regulation of mALT expression. Quantitative RT-PCR assays showed that starvation and the administration of streptozotocin (STZ) decreased HNF4α levels in the kidney of S. aurata, leading to the downregulation of mALT transcription. Analysis of the tissue distribution showed that kidney, liver, and intestine were the tissues with higher mALT and HNF4α expression. Kinetic analysis indicates that mALT enzyme is more efficient in catalyzing the conversion of L: -alanine to pyruvate than the reverse reaction. From these results, we conclude that HNF4α transactivates the mALT promoter and that the low levels of mALT expression found in the kidney of starved and STZ-treated fish result from a decreased expression of HNF4α. Our findings suggest that the mALT isoenzyme plays a major role in oxidazing dietary amino acids, and points to ALT as a target for a biotechnological action to spare protein and optimize the use of dietary nutrients for fish culture.


Assuntos
Alanina Transaminase/metabolismo , Fator 4 Nuclear de Hepatócito/metabolismo , Rim/metabolismo , Mitocôndrias/enzimologia , Dourada/metabolismo , Alanina Transaminase/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Clonagem Molecular , DNA Complementar/genética , Regulação Enzimológica da Expressão Gênica , Fator 4 Nuclear de Hepatócito/genética , Peptídeos e Proteínas de Sinalização Intracelular , Dados de Sequência Molecular , Filogenia , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase em Tempo Real , Elementos de Resposta
8.
J Cardiovasc Pharmacol ; 58(6): 647-53, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21885992

RESUMO

The vascular effects of tamoxifen (Tam) and its metabolites are poorly known. We compared the vasorelaxation induced by Tam and its metabolites (N-desmethyl-Tam, 4-hydroxy-Tam, and endoxifen) in aortic rings from rats using standardized organ bath procedures, and we investigated the mechanisms involved in this effect. Tam and its metabolite-induced vasorelaxation in a concentration-dependent manner. Although 4-hydroxy-Tam and Tam had similar potency (pD2 = 8.5 ± 0.1 vs. 8.8 ± 0.1, respectively) and maximum effect (Emax = 88.5% ± 1.3% vs. 92.6% ± 1.3%, respectively), N-desmethyl-Tam and endoxifen were more potent and showed higher Emax than Tam did (pD2 = 9.0 ± 0.1 and 8.9 ± 0.1; Emax = 101.1% ± 1.8% and 101.0% ± 1.8% for N-desmethyl-Tam and endoxifen, respectively). Although preincubation of aortic rings with the estrogen receptor antagonist ICI 182780 or with the nitric oxide synthase inhibitor Nω-nitro-L-arginine methyl ester hydrochloride induced no changes in the vasorelaxation induced by Tam or 4-hydroxy-Tam, both drugs significantly reduced Emax in response to N-desmethyl-Tam or to endoxifen. Inhibition of cyclooxygenase with indomethacin or the incubation with the prostaglandin D2 and E2 receptor antagonist AH6809 reduced the vasorelaxation-induced Tam and its metabolites by approximately 50%. Preincubation with Nω-nitro-L-arginine methyl ester hydrochloride combined with indomethacin abolished the vasorelaxation-induced Tam and its metabolites. These results show that Tam and its metabolites cause acute vasorelaxation by inducing vasodilator prostanoids synthesis.


Assuntos
Antineoplásicos Hormonais/farmacologia , Aorta Torácica/efeitos dos fármacos , Tamoxifeno/farmacologia , Vasodilatação/efeitos dos fármacos , Animais , Antineoplásicos Hormonais/metabolismo , Aorta Torácica/metabolismo , Estradiol/análogos & derivados , Estradiol/farmacologia , Fulvestranto , Indometacina/farmacologia , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Prostaglandinas/biossíntese , Ratos , Ratos Wistar , Tamoxifeno/análogos & derivados , Tamoxifeno/metabolismo
9.
J Mol Endocrinol ; 45(3): 119-32, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20573775

RESUMO

Alanine aminotransferase (Alt) provides a molecular link between carbohydrate and amino acid metabolism. In the cell context, the predominant Alt isozyme is located in the cytosol. To gain insight into the transcriptional regulation of the cytosolic alt gene (calt), we cloned and characterized the calt promoter from gilthead sea bream (Sparus aurata). Transient transfection of sea bass larvae cells with deleted calt promoter constructs and electrophoretic mobility shift assays allowed us to identify p300 and c-Myb as new factors in the transcriptional regulation of calt expression. Transfection studies carried out with an acetylase-deficient mutant p300 (p300DY) revealed that the acetyltransferase activity of p300 is essential for the p300-mediated transcriptional activation of S. aurata calt. We had previously found up-regulation of liver cAlt2, an alternatively spliced isoform of calt, under gluconeogenic conditions and in streptozotocin (STZ)-treated S. aurata. Quantitative RT-PCR assays showed that increased p300 and c-Myb mRNA levels in the liver of starved S. aurata contribute to enhancing the transcription of cAlt2. Consistently, the administration of insulin decreased both p300 and c-Myb expression. The mRNA levels of p300 and c-Myb were also analyzed in the liver of STZ-induced diabetic S. aurata. Treatment with STZ increased the expression of p300, whereas it decreased c-Myb. Our findings suggest an involvement of p300 and c-Myb in up-regulation of cAlt2 in the liver of S. aurata under starvation. In addition, these results provide evidence for a role of p300 in diabetes.


Assuntos
Alanina Transaminase/genética , Citosol/enzimologia , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-myb/metabolismo , Dourada/genética , Ativação Transcricional/genética , Fatores de Transcrição de p300-CBP/metabolismo , Região 5'-Flanqueadora/genética , Animais , Sequência de Bases , Bass , Clonagem Molecular , Sequência Consenso/genética , Citosol/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Histona Acetiltransferases , Insulina/farmacologia , Fígado/metabolismo , Dados de Sequência Molecular , Complexos Multiproteicos/metabolismo , Mutação/genética , Ligação Proteica/efeitos dos fármacos , Elementos de Resposta/genética , Deleção de Sequência
10.
Int J Biochem Cell Biol ; 40(12): 2833-44, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18582594

RESUMO

Increased alanine aminotransferase (ALT) activity is associated with insulin resistance and the development of type 2 diabetes. The aim of this study was to characterize the modulation of cytosolic ALT expression in liver of gilthead sea bream (Sparus aurata) under conditions associated with increased gluconeogenesis and in streptozotocin (STZ)-treated fish. RT- and RACE-PCR assays allowed us to isolate a novel ALT isozyme (cALT2) generated from alternative splicing of cALT gene in S. aurata. HEK293 cells transfected with constructs expressing cALT2 as a C-terminal fusion with the enhanced green fluorescent protein allowed us to demonstrate that cALT2 is cytosolic. To unravel the molecular functions of cALT1 and cALT2 in liver of S. aurata, we examined tissue distribution, kinetic characterization of piscine cALT isozymes expressed in Saccharomyces cerevisiae, and regulation of hepatic cALT1 and cALT2 expression in various metabolic conditions. Kinetic analysis indicates that cALT2 is more efficient in catalysing the conversion of l-alanine to pyruvate than cALT1. Starvation increased cALT2 expression and decreased cALT1 mRNA in liver. Opposite effects were found in regularly fed fish at postprandial time 4-8h, and 6h after treatment with glucose or insulin. From these results we conclude that increased cALT2 expression occurred in liver under gluconeogenic conditions, while cALT1 was predominant during postprandial utilization of dietary nutrients. Since up-regulation of hepatic cALT2 expression occurred in STZ-induced diabetic S. aurata, increased hepatic cALT2 expression may be a promising marker in the prognosis of diabetes.


Assuntos
Alanina Transaminase/genética , Gluconeogênese/genética , Fígado/metabolismo , Splicing de RNA , Dourada/genética , Alanina Transaminase/metabolismo , Animais , Citosol/química , Citosol/metabolismo , Isoenzimas/genética , Isoenzimas/metabolismo , Fígado/química , Extratos Hepáticos/metabolismo , Dourada/metabolismo
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