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1.
Pediatr Blood Cancer ; 71(7): e31007, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38654470

RESUMO

OBJECTIVES: In the etiology of childhood cancers, many genetic and environmental factors play a role. One of these factors could be cigarette smoking, and the main source of tobacco smoke exposure of children is parental smoking. However, establishing a causal relationship between parental smoking and childhood cancers has proven challenging due to difficulties in accurately detecting tobacco smoke exposure METHODS: To address this issue, we used hair cotinine analysis and a questionnaire to get information about tobacco smoke exposures of pediatric cancer patients and healthy children. A total of 104 pediatric cancer patients and 99 healthy children participated in our study. Parental smoking behaviors (pre-conceptional, during pregnancy, and current smoking) and environmental tobacco smoke (ETS) exposures of children are compared. RESULTS: We have found no differences between two groups by means of maternal smoking behaviors. However, the rates of paternal pre-conceptional smoking and smoking during pregnancy were significantly low in cancer patients (p < .05). These data suggest that social desirability bias among fathers of cancer patients may have contributed to this discrepancy. According to questionnaire, cancer patients had significantly lower ETS exposures than healthy children (p < .05). However, ETS exposure assessment through cotinine analysis demonstrated that cancer patients had higher exposure to ETS compared to healthy children (p < .001). CONCLUSION: Our findings provide evidence supporting the potential role of smoking as a risk factor for childhood cancers. This study also revealed that questionnaires could cause biases. We suggest that cotinine analysis along with validated questionnaires can be used to prevent biases in studies of tobacco smoke in the etiology of childhood cancers.


Assuntos
Cotinina , Cabelo , Neoplasias , Poluição por Fumaça de Tabaco , Humanos , Feminino , Poluição por Fumaça de Tabaco/efeitos adversos , Poluição por Fumaça de Tabaco/análise , Masculino , Cotinina/análise , Criança , Inquéritos e Questionários , Neoplasias/etiologia , Neoplasias/epidemiologia , Cabelo/química , Pré-Escolar , Pais , Gravidez , Adulto , Estudos de Casos e Controles , Adolescente , Fumar/efeitos adversos , Seguimentos
2.
Drug Dev Res ; 85(4): e22224, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38867474

RESUMO

The mammalian cytoplasmic protein SIRT2, a class III histone deacetylase family member, possesses NAD+-dependent lysine deacetylase/deacylase activity. Dysregulation of SIRT2 has been implicated in the pathogenesis of several diseases, including neurological and metabolic disorders and cancer; thus, SIRT2 emerges as a potential therapeutic target. Herein, we identified a series of diaryl acetamides (ST61-ST90) by the structural optimization of our hit STH2, followed by enhanced SIRT2 inhibitory potency and selectivity. Among them, ST72, ST85, and ST88 selectively inhibited SIRT2 with IC50 values of 9.97, 5.74, and 8.92 µM, respectively. Finally, the entire study was accompanied by in silico prediction of binding modes of docked compounds and the stability of SIRT2-ligand complexes. We hope our findings will provide substantial information for designing selective inhibitors of SIRT2.


Assuntos
Acetamidas , Sirtuína 2 , Sirtuína 2/antagonistas & inibidores , Sirtuína 2/química , Sirtuína 2/metabolismo , Humanos , Acetamidas/química , Acetamidas/farmacologia , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/química
3.
Bioorg Chem ; 123: 105746, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35358824

RESUMO

Sirtuin 2 (SIRT2), member of sirtuin family, belongs to class III histone deacetylases (HDACs) and is majorly cytosolic with occasional nuclear translocation. The enzymatic activity of SIRT2 is dependent on nicotinamide adenine dinucleotide (NAD+) and SIRT2 regulates post-translational modifications that are responsible for deacetylation of lysine residues in histone and non-histone substrates. SIRT2, thus affects most likely multiple cellular processes, such as signaling, gene expression, aging, autophagy, and has been identified as potential drug target in relation to inflammation, neurodegenerative diseases and cancer. Therefore, probing potential selective inhibitors is essential for the accurate understanding of enzyme functions. Here, we report a series of heteroaryl-2-carboxamide hybrids bearing substituted benzyl or substituted phenoxy group at the 5-position of the central heterocyclic ring. The synthesized compounds were screened against SIRT1-3 and MCF-7 human breast cancer cell line to evaluate their biological activity. The best SIRT2 inhibition profiles were displayed by ST29 (SIRT2 IC50 = 38.69 µM) and ST30 (SIRT2 IC50 = 43.29 µM) with excellent selectivity against SIRT2 over SIRT1 and SIRT3. Molecular docking study of the synthesized compounds into SIRT2 active site was performed to rationalize the remarkable SIRT2 inhibitory activity. Furthermore, we performed all-atom, explicit-solvent molecular dynamics (MD) simulations and end-point binding free energy calculations using molecular mechanics/generalized Born surface area (MM/GBSA) method to evaluate whether this design strategy was successfully deployed. The results implied that the binding poses and ligand affinities were predicted without significant loss of accuracy. Conclusively, the developed chemotypes were advocated as promising leads for SIRT2 inhibition and required further investigation for SIRT2-targeted drug discovery and development.


Assuntos
Inibidores de Histona Desacetilases , Sirtuína 2 , Inibidores de Histona Desacetilases/química , Inibidores de Histona Desacetilases/farmacologia , Humanos , Simulação de Acoplamento Molecular , Sirtuína 1/metabolismo , Relação Estrutura-Atividade , Tiadiazóis
4.
Haemophilia ; 27(6): e747-e753, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34614537

RESUMO

INTRODUCTION: Haemophilia is a bleeding disorder that occurs due to the deficiency of coagulation factors, and the angiogenesis process is an important process underlying the pathophysiology of haemophilic arthropathy. The role of the new adipocytokine endoglin (ENG) in patients with haemophilia is not yet known. AIM: The aim of this study is to evaluate the association between ENG protein and angiogenesis-related cytokines in patients with haemophilia for the first time. METHODS: Plasma protein levels and mRNA expressions of ENG and various angiogenesis-associated cytokines were compared in blood samples collected from 28 patients with haemophilia A or B and 29 healthy volunteers. The relationship between the cytokines and ENG were determined by correlation analysis. RESULTS: Plasma ENG levels and angiogenic markers were found to be significantly higher in patients with haemophilia compared to controls. Real-time PCR studies showed that mRNA expressions of ENG, vascular endothelial growth factor A, hypoxia-inducible factor A, and prostaglandin E2 increased in patients with haemophilia. Correlation analysis showed a significant positive correlation between ENG and angiopoietin-2 levels in the haemophilia group. Besides, a significant decrease in annexin-V binding to platelets in haemophilia patients compared to control was found to be related to the bleeding profiles in the patients. CONCLUSIONS: This study determined that ENG protein may be involved in the formation of angiogenesis in haemophilia patients and its effects may be related to angiogenetic marker angiopoietin-2 in this process. Our findings contribute to the literature during the determination of target proteins in haemophilia treatment.


Assuntos
Hemofilia A , Fator A de Crescimento do Endotélio Vascular , Angiopoietina-2/genética , Estudos de Casos e Controles , Endoglina/genética , Hemofilia A/genética , Humanos , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/genética
5.
Bioorg Med Chem ; 30: 115961, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33360574

RESUMO

Sirtuins (SIRTs) are a class of nicotinamide adenine dinucleotide (NAD+)-dependent protein histone deacetylases (HDACs) that are evolutionarily conserved from bacteria to mammals. This group of enzymes catalyses the reversible deacetylation of lysine residues in the histones or non-histone substrates using NAD+ as a cosubstrate. Numerous studies have demonstrated that the aberrant enzymatic activity of SIRTs has been linked to various diseases like diabetes, cancer, and neurodegenerative disorders. Previously, we performed a pharmacophore-based virtual screening campaign and an aryloxybenzamide derivative (1) displaying SIRT1/2 inhibitory effect was identified as a hit compound. In the current study, the hit-to-lead optimization on the hit compound was explored in order to improve the SIRT binding and inhibition. Fourteen compounds, ten of which were new, have been synthesized and subjected to in vitro biological evaluation for their inhibitory activity against SIRT1-3. By the structural modifications performed, a significant improvement was observed in selective SIRT1 inhibition for ST01, ST02, and ST11 compared to that of the hit compound. The highest SIRT2 inhibitory activity was observed for ST14, which was designed according to compatibility with pharmacophore model developed for SIRT2 inhibitors and thus, providing the interactions required with key residues in SIRT2 active site. Furthermore, ST01, ST02, ST11, and ST14 were subjected to in vitro cytotoxicity assay against MCF-7 human breast cancer cell line to determine the influence of the improvement in SIRT1/2 inhibition along with the structural modifications on the cytotoxic properties of the compounds. The cytotoxicity of the compounds was found to be correlated with their SIRT inhibitory profiles indicating the effects of SIRT1/2 inhibition on cancer cell viability. Overall, this study provides structural insights for further inhibitor improvement.


Assuntos
Antineoplásicos/farmacologia , Benzamidas/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Sirtuína 1/antagonistas & inibidores , Sirtuína 2/antagonistas & inibidores , Sirtuína 3/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Benzamidas/síntese química , Benzamidas/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores de Histona Desacetilases/síntese química , Inibidores de Histona Desacetilases/química , Humanos , Células MCF-7 , Simulação de Acoplamento Molecular , Estrutura Molecular , Sirtuína 1/metabolismo , Sirtuína 2/metabolismo , Sirtuína 3/metabolismo , Relação Estrutura-Atividade
6.
Bioorg Chem ; 101: 104028, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32645482

RESUMO

A new series of pyrimidine derivatives containing aryl urea moieties was designed and synthesized. The anticancer activities of all compounds were evaluated in vitro against colon and prostat cancer cell lines by MTT assay. Among these compounds, 4b exhibited the highest cytotoxic activity against SW480 cancer cell line with IC50 value of 11.08 µM. Mechanistic studies showed that compound 4b arrested cell cycle at G2/M phase and induced apoptosis through upregulating Bax, Ikb-α and cleaved PARP and downregulating Bcl-2 expression levels. Moreover, compound 4b induced loss of mitochondrial membrane potential in SW480 cells. These results suggest that pyrimidine with urea moieties could be a template for designing new anticancer agents.


Assuntos
Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Pirimidinas/síntese química , Pirimidinas/uso terapêutico , Ureia/análogos & derivados , Antineoplásicos/farmacologia , Humanos , Estrutura Molecular , Pirimidinas/farmacologia , Relação Estrutura-Atividade
7.
An Acad Bras Cienc ; 92(4): e20200548, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33237147

RESUMO

Combination therapies are becoming increasingly important to develop an effective treatment in cancer. Lonidamine is frequently used in cancer treatment, but it's often preferred to be used in combination with other drugs because of its side effects. In the present study, the efficacy of the combination of lonidamine with quercetin, a flavonoid of natural origin, on human MCF-7 breast cancer cells was evaluated. The results showed that the combined use of the compounds significantly increased cytotoxicity compared to administration alone (p<0.0001). In addition, while lonidamine induced a cell cycle arrest in the G2/M phase, administration of quercetin and its combination with lonidamine arrested the cell division at S point, indicating the synergistic strength of quercetin on cytotoxicity. The combination of quercetin and lonidamine significantly induced apoptosis of MCF-7 cells (p<0.0001) and increased caspase levels (p<0.0001). In this study, the combination of quercetin and lonidamine has been evaluated for the first time and the combination treatment decreased MMP-2/-9 mRNA expression more potently than the effects of the compounds alone. The results showed that lonidamine was more effective when combined with quercetin, and their combination may be a candidate for a novel strategy of treatment for breast cancer.


Assuntos
Neoplasias da Mama , Quercetina , Apoptose , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Regulação para Baixo , Humanos , Indazóis , Células MCF-7 , Metaloproteinase 2 da Matriz/genética , Quercetina/farmacologia , RNA Mensageiro/genética
8.
An Acad Bras Cienc ; 92(4): e20191533, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33237139

RESUMO

Seseli L. is an important genus of the Apiaceae family, with a large number of aromatic species. It is used in traditional medicine extensively, but there is quite limited information on their phytochemicals and biological activities. Seseli petraeum M. Bieb. grows in Northern Anatolia, and there are no phytochemical studies on this species. In the present study, we aimed to investigate the effect of the extracts of S. petraeum on A549 lung cancer cell proliferation. For this purpose, the antiproliferative effect was determined via MTT assay, and the extracts obtained from the root of S. petraeum showed a significant inhibitory effect on cell proliferation. The hexane extract of the root exhibited potent inhibition on A549 cancer cell growth at the 24th hour with 3.432 mg/mL IC50 value. The results also showed that the hexane extract had displayed cytotoxic effect through an arrest at the G0/G1 phase of the cell cycle and induced apoptosis as well as DNA damage of A549 cells. Consequently, this study demonstrated the antiproliferative potential of the extracts from S. petraeum, especially hexane extract from the roots. Further studies are required to identify the mechanisms underlying these effects.


Assuntos
Apiaceae , Neoplasias Pulmonares , Células A549 , Apoptose , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Pontos de Checagem da Fase G1 do Ciclo Celular , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Extratos Vegetais/farmacologia
9.
Arch Pharm (Weinheim) ; 353(8): e2000059, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32419228

RESUMO

A series of novel indole hydrazide derivatives was synthesized and evaluated for their anticancer activities. Compound 12 exhibited the highest antiproliferative activity against the MCF-7 cell line, with an IC50 value of 3.01 µM. Treatment of MCF-7 cells with compound 12 led to cell cycle arrest at the G0/G1 phase and also displayed a significant annexin V binding pattern, indicating that compound 12 is effective in apoptotic cell death. The Western blot analysis showed that compound 12 increased the expression of proapoptotic Bax and decreased the levels of the antiapoptotic Bcl-2 protein. It was also observed that MCF-7 cells treated with compound 12 showed reduced levels of procaspase-3 and -9 proteins. Moreover, compound 12 treatment induced a significant DNA damage in MCF-7 cells by increasing H2AX and ATM phosphorylation.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Hidrazinas/farmacologia , Indóis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Hidrazinas/síntese química , Hidrazinas/química , Indóis/síntese química , Indóis/química , Estrutura Molecular , Relação Estrutura-Atividade
10.
Bioorg Chem ; 83: 511-519, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30458413

RESUMO

In this work we described the synthesis and evaluation of cytotoxic and apoptotic activity of novel pyrrolopyrimidine derivatives against A549, PC3 and MCF-7 cells. Among the synthesized compounds, 6b, 8a, 9a and 7a, 8b displayed the significant cytotoxic activities against A549 and PC3 cells with IC50 value of 0.35, 1.48, 1.56 and 1.04, 1.89 µM, respectively. It was found that A549 cells were more sensitive to synthesized compounds than PC3 and MCF-7 cells. In order to evaluate the mechanism of cytotoxic activity in A549, compounds 6b, 8a and 9a were selected for further studies. Annexin V binding assay and western blot analysis results revealed that 6b, 8a and 9a induced apoptosis in A549 cells by intrinsic apoptotic pathway through the activation pro-apoptotic proteins such as Bim, Bax, Bak, Puma and deactivation of anti-apoptotic proteins including Bcl-2, Mcl-1 and Bcl-XL accompanied by the activation of caspase-3, caspase-9 and cleavage of PARP. Also, compounds 6b, 8a and 9a triggered apoptosis in HCT116 wt cells via activation of caspase-3 and caspase-9, but not in HCT116 Bax/Bak KO cells, indicating resistance to 6b, 8a and 9a treatment.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Pirimidinas/farmacologia , Pirróis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Desenho de Fármacos , Humanos , Mesilato de Imatinib/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Pirimidinas/síntese química , Pirimidinas/química , Pirróis/síntese química , Pirróis/química
11.
Phytother Res ; 33(2): 397-402, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30450754

RESUMO

In cancer treatment, which is a major cause of mortality today, combination studies with clinically used chemotherapeutics are becoming increasingly important as much as investigating the effects of novel natural compounds. In this context, phytoalexins constitute an important group due to their unique structure. Brassinin is an essential indole phytoalexin and is a biosynthetic precursor for other phytoalexins. The purpose of this study was to evaluate the anticancer effects of brassinin in combination with imatinib in SW480 cells. In the study, it was observed that brassinin-imatinib combination significantly increased cytotoxicity compared with the single treatment of both compounds and inhibited cell cycle at G0/G1 phase. Annexin V binding and fluorescence imaging assays showed that the combination of brasinin-imatinib induces apoptosis in a dose-dependent manner. Furthermore, the effect of brassinin on the activity of MMP-9 in SW480 cells was evaluated for the first time, and it was detected that MMP-9 activity was significantly reduced. The combination of brassinin-imatinib was found to inhibit MMP-9 activity as well as relative MMP-9 gene expression on a higher level compared with control and compounds alone. Our findings have revealed that the combination of brassinin-imatinib synergistically induces cytotoxicity and apoptosis in SW480 cells. The findings on MMP-9 downregulation have also revealed the anti-metastatic potential of treatment.


Assuntos
Neoplasias do Colo/tratamento farmacológico , Mesilato de Imatinib/farmacologia , Indóis/farmacologia , Metaloproteinase 9 da Matriz/metabolismo , Tiocarbamatos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Humanos , Sesquiterpenos/farmacologia , Fitoalexinas
12.
Sleep Breath ; 22(4): 1053-1061, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29453640

RESUMO

BACKGROUND: The purpose of this study was to investigate the effect of semi-rapid maxillary expansion (SRME) orthodontic treatment on biomarkers and respiratory parameters in children with obstructive sleep apnea syndrome (OSAS) and maxillary transverse deficiency. METHODS: Thirty children with OSAS were included in this study. Fifteen children were enrolled as control, and 15 children were subjected to SRME orthodontic treatment method for 5 months. Beside respiratory parameters, pharyngeal area, dental arch, and postero-anterior widths and the levels of OSAS biomarkers in serum and urine were measured. RESULTS: Pharyngeal airway space, dental arch, and postero-anterior widths were increased after SRME treatment. Sleep tests showed a decrease in the apnea-hypopnea index (AHI) after 5-month control/treatment duration. Serum kallikrein (KLK)1 levels decreased significantly in the treatment group. There was a significant increase in serum orosomucoid (ORM)2 levels and a decrease in urine perlecan levels in the control group after a 5-month follow-up. A significant negative correlation between serum ORM2, perlecan, gelsolin, and KLK1 levels and intercanin width, as well as between serum ORM2 and KLK1 levels and intermolar width, was observed. CONCLUSIONS: SRME treatment can be considered as a useful approach in children with OSAS. A further investigation of OSAS-related biomarkers and their relationship with sleep and orthodontic parameters is needed for providing easier and reliable modulatory strategies in the treatment of OSAS.


Assuntos
Nível de Alerta/fisiologia , Técnica de Expansão Palatina , Índice de Gravidade de Doença , Apneia Obstrutiva do Sono/terapia , Biomarcadores/sangue , Biomarcadores/urina , Criança , Feminino , Seguimentos , Humanos , Masculino , Polissonografia , Apneia Obstrutiva do Sono/sangue , Apneia Obstrutiva do Sono/urina
13.
Eur J Appl Physiol ; 118(3): 585-593, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29327169

RESUMO

PURPOSE: While several studies demonstrated the occurrence of intermuscular mechanical interactions, the physiological significance of these interactions remains a matter of debate. The purpose of this study was to quantify the localized changes in the shear modulus of the gastrocnemius lateralis (GL), monoarticular dorsi- and plantar-flexor muscles induced by a change in knee angle. METHOD: Participants underwent slow passive ankle rotations at the following two knee positions: knee flexed at 90° and knee fully extended. Ultrasound shear wave elastography was used to assess the muscle shear modulus of the GL, soleus [both proximally (SOL-proximal) and distally (SOL distal)], peroneus longus (PERL), and tibialis anterior (TA). This was performed during two experimental sessions (experiment I: n = 11; experiment II: n = 10). The shear modulus of each muscle was compared between the two knee positions. RESULTS: The shear modulus was significantly higher when the knee was fully extended than when the knee was flexed (P < 0.001) for the GL (averaged increase on the whole range of motion: + 5.8 ± 1.3 kPa), SOL distal (+ 4.5 ± 1.5 kPa), PERL (+ 1.1 ± 0.7 kPa), and TA (+ 1.6 ± 1.0 kPa). In contrast, a lower SOL-proximal shear modulus (P < 0.001, - 5.9 ± 1.0 kPa) was observed. CONCLUSION: As the muscle shear modulus is linearly related to passive muscle force, these results provide evidence of a non-negligible intermuscular mechanical interaction between the human lower leg muscles during passive ankle rotations. The role of these interactions in the production of coordinated movements requires further investigation.


Assuntos
Tornozelo/fisiologia , Articulação do Joelho/fisiologia , Músculo Esquelético/fisiologia , Adulto , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Contração Muscular , Distribuição Aleatória
14.
Med Princ Pract ; 27(6): 549-554, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30184546

RESUMO

BACKGROUND/AIMS: Spexin is a novel peptide which has a potential role as a biomarker of insulin resistance, diabetes, and obesity. Our aim was to measure spexin levels in lean type 1 diabetic patients and its relevance to glycemic parameters without the presence of obesity or insulin resistance. SUBJECTS AND METHODS: This cross-sectional study included 29 type 1 and 30 type 2 diabetic patients and a control group of 23 healthy subjects with adjusted age, sex, and body mass index (BMI). Height and weight were measured using standard techniques. Glucose levels, triglycerides, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, serum cortisol levels, and spexin levels were measured in each patient. RESULTS: The median fasting serum spexin levels were significantly lower in patients with type 1 and type 2 diabetes than in control subjects (p = 0.008 and p = 0.041, respectively). Spexin levels were not correlated with glycemic parameters, lipids, BMI, cortisol levels, and thyroid-stimulating hormone (p > 0.05). Only age turned out to be correlated with spexin levels in patients with type 1 diabetes when we analyzed the groups separately. Regression models, including age and diabetes duration, revealed no association between age and spexin levels. Regression models, including cortisol, BMI, and HbA1c, revealed no association with spexin levels within each group. CONCLUSION: The presence of type 1 diabetes is associated with lower spexin levels, independent of glucose, lipid parameters, and BMI. The expression of spexin in the pancreas apart from the current glycemic control of the patients may be the main determinant of spexin levels in type 1 diabetic patients.


Assuntos
Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 2/sangue , Hormônios Peptídicos/sangue , Adulto , Análise de Variância , Biomarcadores/sangue , Índice de Massa Corporal , Estudos Transversais , Feminino , Hemoglobinas Glicadas/análise , Humanos , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Turquia , Adulto Jovem
15.
Muscle Nerve ; 51(1): 106-16, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24796973

RESUMO

INTRODUCTION: We tested the hypothesis that BTX-A diminishes epimuscular myofascial force transmission (EMFT) within an intact muscle compartment. METHODS: The tibialis anterior (TA) and extensor hallucis longus (EHL) muscles were kept at constant length, whereas the position of the extensor digitorum longus (EDL) muscle was changed exclusively. Two groups of Wistar rats were tested: a control group (no BTX-A injected) and a BTX group (0.1 unit of BTX-A injected into the mid-belly of TA). RESULTS: In controls, distally altered EDL position affected EDL distal and proximal forces and proximodistal force differences, indicating substantial EMFT. In the BTX group, EDL forces measured at the most proximal position did not change significantly with altered muscle position, and EDL proximodistal force differences became minimized. CONCLUSIONS: Use of BTX-A diminishes EMFT. It may be relevant clinically that BTX-A compromises intermuscular mechanical interaction, as recent studies have shown that such an interaction plays a role in the abnormal mechanics of spastic muscle.


Assuntos
Toxinas Botulínicas Tipo A/farmacologia , Contração Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Fármacos Neuromusculares/farmacologia , Análise de Variância , Animais , Fenômenos Biomecânicos , Estimulação Elétrica , Masculino , Ratos , Ratos Wistar , Estresse Mecânico
16.
Muscle Nerve ; 52(3): 412-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25640922

RESUMO

INTRODUCTION: The aim of this study was to test the hypothesis that the increased number of new motor endplates induced by botulinum toxin type A (BTX-A) injection before nerve injury would be reinnervated after nerve repair, resulting in greater force generation. METHODS: Thirty male Wistar rats were divided randomly into 3 groups: (1) controls; (2) a group with saline solution injection; and (3) a group with BTX-A injection into gastrocnemius muscle (BTX group). Thirty-six days after the injections the left sciatic nerve was divided and coapted in all groups. Eight weeks later, muscle forces were measured, and histological samples were collected. RESULTS: No differences in the number of innervated endplates were found between the groups, but the number of denervated endplates was higher in the BTX group, as was the muscle tissue degeneration score. The BTX group showed distal muscle force measurements of up to 25.8% less compared with the control group. CONCLUSION: Although BTX-A injection increases the number of motor endplates, they are not functional.


Assuntos
Toxinas Botulínicas Tipo A/farmacologia , Placa Motora/efeitos dos fármacos , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Fármacos Neuromusculares/farmacologia , Nervo Isquiático/lesões , Animais , Masculino , Músculo Esquelético/inervação , Músculo Esquelético/patologia , Ratos , Ratos Wistar , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/cirurgia
17.
Muscle Nerve ; 49(6): 866-78, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24122931

RESUMO

INTRODUCTION: The goal of this study was to test the hypothesis that botulinum toxin type A (BTX-A) injection in rat tibialis anterior (TA) muscle affects the mechanics of its bi-articular synergist, both actively and passively. METHODS: Two groups of Wistar rats were tested: control (no BTX-A) and BTX (0.1 U of BTX-A) animals were injected exclusively to the mid-belly of TA. Extensor digitorum longus (EDL) muscle isometric forces were measured after proximal and distal lengthening. RESULTS: Five days after injection, BTX-A administration changed EDL mechanics: (1) active forces decreased (proximal muscle length dependently); (2) length range of active force exertion decreased both proximally and distally; and (3) passive muscle forces increased. CONCLUSIONS: Effects of BTX-A appear to not be limited to decreased active muscle tone, but may cause also a narrower active range of movement and increased passive resistance. Through spread of BTX-A to a bi-articular muscle, such effects are plausible for both joints spanned.


Assuntos
Toxinas Botulínicas Tipo A/farmacologia , Contração Isométrica/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Animais , Fenômenos Biomecânicos/efeitos dos fármacos , Fenômenos Biomecânicos/efeitos da radiação , Toxinas Botulínicas Tipo A/administração & dosagem , Injeções Intramusculares , Contração Isométrica/fisiologia , Masculino , Modelos Animais , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Esforço Físico/efeitos dos fármacos , Esforço Físico/fisiologia , Ratos , Ratos Wistar
18.
J Biomech ; 168: 112134, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38723428

RESUMO

Connective tissues can be recognized as an important structural support element in muscles. Recent studies have also highlighted its importance in active force generation and transmission between muscles, particularly through the epimysium. In the present study, we aimed to investigate the impact of the endomysium, the connective tissue surrounding muscle fibers, on both passive and active force production. Pairs of skeletal muscle fibers were extracted from the extensor digitorum longus muscles of rats and, after chemical skinning, their passive and active force-length relationships were measured under two conditions: (i) with the endomysium between muscle fibers intact, and (ii) after its dissection. We found that the dissection of the endomysium caused force to significantly decrease in both active (by 22.2 % when normalized to the maximum isometric force; p < 0.001) and passive conditions (by 25.9 % when normalized to the maximum isometric force; p = 0.034). These findings indicate that the absence of endomysium compromises muscle fiber's not only passive but also active force production. This effect may be attributed to increased heterogeneity in sarcomere lengths, enhanced lattice spacing between myofilaments, or a diminished role of trans-sarcolemmal proteins due to dissecting the endomysium. Future investigations into the underlying mechanisms and their implications for various extracellular matrix-related diseases are warranted.


Assuntos
Fibras Musculares Esqueléticas , Animais , Ratos , Fibras Musculares Esqueléticas/fisiologia , Ratos Wistar , Tecido Conjuntivo/fisiologia , Sarcômeros/fisiologia , Masculino , Músculo Esquelético/fisiologia , Fenômenos Biomecânicos , Contração Isométrica/fisiologia , Contração Muscular/fisiologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-39092648

RESUMO

BACKGROUND: Ballota acetabulosa native to the Mediterranean region, belonging to the Lamiaceae family, holds significance in folk medicine. Externally, it is applied for treating cuts and burns, while internally, it is utilized to alleviate inflammation, suppress cough, and address gastrointestinal issues. METHODS: This study aimed to investigate the chemical composition of the essential oil of Ballota acetabulosa and to evaluate the antioxidant capacity of the essential oil, as well as the aqueous and ethanolic extracts of the plant. Essential oil analysis was performed using Gas Chromatography- Mass Spectrometry (GC-MS), while 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and inhibition of lipid peroxidation assays were applied to the essential oil, water, and ethanol extracts of the plant. RESULTS: Spathulenol was found to be the predominant constituent of the essential oil, comprising 25.03% of the oil. Compared to the control group (Propyl gallate for DPPH, IC50 0.109; BHT for inhibition of lipid peroxidation, IC50 0.133), the essential oil was found to have insignificant antioxidant activity (IC50 value 10.395 mg/mL for DPPH, 1.051 mg/mL for inhibition of lipid peroxidation). Moreover, ethanolic extract (IC50 value 1.583 mg/mL for DPPH, 0.029 mg/mL for inhibition of lipid peroxidation) exerted more antioxidant activity than aqueous extract (IC50 value 1.9017 mg/mL for DPPH, 0.161 mg/mL for inhibition of lipid peroxidation). CONCLUSION: Hitherto, this is the earliest report on the composition and activity of the essential oil Ballota acetabulosa. However, further investigation of different antioxidant capacity assays is suggested to highlight potential variations in mechanisms of action and subsequent results. Everything considered, this study advances the comprehension of the chemical composition and possible therapeutic uses of Ballota acetabulosa, highlighting the need for more research into its uses.

20.
Sci Rep ; 13(1): 20062, 2023 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-37974024

RESUMO

Aging leads to a decline in muscle mass and force-generating capacity. Ultrasound shear wave elastography (SWE) is a non-invasive method to capture age-related muscular adaptation. This study assessed biceps brachii muscle (BB) mechanics, hypothesizing that shear elastic modulus reflects (i) passive muscle force increase imposed by length change, (ii) activation-dependent mechanical changes, and (iii) differences between older and younger individuals. Fourteen healthy volunteers aged 60-80 participated. Shear elastic modulus, surface electromyography, and elbow torque were measured at five elbow positions in passive and active states. Data collected from young adults aged 20-40 were compared. The BB passive shear elastic modulus increased from flexion to extension, with the older group exhibiting up to 52.58% higher values. Maximum elbow flexion torque decreased in extended positions, with the older group 23.67% weaker. Significant effects of elbow angle, activity level, and age on total and active shear elastic modulus were found during submaximal contractions. The older group had 20.25% lower active shear elastic modulus at 25% maximum voluntary contraction. SWE effectively quantified passive and activation-dependent BB mechanics, detecting age-related alterations at rest and during low-level activities. These findings suggest shear elastic modulus as a promising biomarker for identifying altered muscle mechanics in aging.


Assuntos
Técnicas de Imagem por Elasticidade , Articulação do Cotovelo , Adulto Jovem , Humanos , Técnicas de Imagem por Elasticidade/métodos , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiologia , Ultrassonografia , Cotovelo/diagnóstico por imagem , Cotovelo/fisiologia , Articulação do Cotovelo/diagnóstico por imagem , Articulação do Cotovelo/fisiologia , Módulo de Elasticidade/fisiologia
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