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1.
Molecules ; 29(10)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38792080

RESUMO

Tumor cells in hypoxic conditions control cancer metabolism and angiogenesis by expressing HIF-1α. Tanshinone is a traditional Chinese medicine that has been shown to possess antitumor properties and exerts a therapeutic impact on angiogenesis. However, the precise molecular mechanism responsible for the antitumor activity of 3-Hydroxytanshinone (3-HT), a type of tanshinone, has not been fully understood. Therefore, our study aimed to investigate the mechanism by which 3-HT regulates the expression of HIF-1α. Our findings demonstrate that 3-HT inhibits HIF-1α activity and expression under hypoxic conditions. Additionally, 3-HT inhibits hypoxia-induced angiogenesis by suppressing the expression of VEGF. Moreover, 3-HT was found to directly bind to α-enolase, an enzyme associated with glycolysis, resulting in the suppression of its activity. This inhibition of α-enolase activity by 3-HT leads to the blockade of the glycolytic pathway and a decrease in glycolysis products, ultimately altering HIF1-α expression. Furthermore, 3-HT negatively regulates the expression of HIF-1α by altering the phosphorylation of AMP-activated protein kinase (AMPK). Our study's findings elucidate the mechanism by which 3-HT regulates HIF-1α through the inhibition of the glycolytic enzyme α-enolase and the phosphorylation of AMPK. These results suggest that 3-HT holds promise as a potential therapeutic agent for hypoxia-related angiogenesis and tumorigenesis.


Assuntos
Glicólise , Subunidade alfa do Fator 1 Induzível por Hipóxia , Fosfopiruvato Hidratase , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fosfopiruvato Hidratase/metabolismo , Fosfopiruvato Hidratase/genética , Glicólise/efeitos dos fármacos , Humanos , Abietanos/farmacologia , Hipóxia Celular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Linhagem Celular Tumoral , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo
2.
Int J Hyg Environ Health ; 259: 114385, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38676994

RESUMO

AIMS: Recent epidemiologic research has examined the relationship between perfluoroalkyl and polyfluoroalkyl substances (PFAS) and diabetes mellitus with inconclusive findings. In this cross-sectional study, we aimed to explore the association between serum PFAS concentrations and the prevalence of prediabetes and pre-diagnostic diabetes in the general Korean population as well as the combined effects of exposure to mixed PFAS compounds. METHODS: We analyzed data from participants aged ≥19 years enrolled in the Korean National Environmental Health Survey Cycle 4 (2018-2020). Individuals diagnosed with diabetes were excluded to minimize potential bias. We identified cases of pre-diagnostic diabetes based on the HbA1c level ≥6.5% and prediabetes as HbA1c levels of 5.7-6.49%. Serum concentrations of PFAS, including perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDeA), perfluorohexane sulfonic acid (PFHxS), and perfluorooctane sulfonic acid (PFOS), were quantified using high-performance liquid chromatography-tandem mass spectrometry. Survey-weighted logistic regression models were used to assess the relationships between PFAS levels and diabetes risk, adjusting for covariates. Additionally, Bayesian kernel machine regression (BKMR) was used to investigate the combined effects of exposure to mixed PFAS compounds. RESULTS: In the study population excluding participants with diagnosed diabetes (n = 2709), the prevalence of pre-diagnostic diabetes and prediabetes was 4.8% and 30.1%, respectively. Significant positive associations were found between serum PFHxS and PFOS quartiles and pre-diagnostic diabetes risk. Likewise, among those without diagnosed or pre-diagnostic diabetes (n = 2579), the highest quartiles of PFDeA, PFHxS, and PFOS and the overall PFAS level were associated with an increased risk of prediabetes compared with the lowest quartiles. BKMR analysis revealed a significant positive association between overall serum PFAS level and prediabetes risk, which was most marked for PFOS. CONCLUSIONS: These findings highlight the potential health implications of PFAS exposure and prediabetes risk. Further research is needed to validate these associations and identify potential mechanistic pathways.


Assuntos
Ácidos Alcanossulfônicos , Diabetes Mellitus , Poluentes Ambientais , Fluorocarbonos , Humanos , Fluorocarbonos/sangue , Pessoa de Meia-Idade , Feminino , República da Coreia/epidemiologia , Masculino , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/sangue , Adulto , Poluentes Ambientais/sangue , Ácidos Alcanossulfônicos/sangue , Estudos Transversais , Idoso , Inquéritos Epidemiológicos , Exposição Ambiental/efeitos adversos , Prevalência , Caprilatos/sangue , Estado Pré-Diabético/sangue , Estado Pré-Diabético/epidemiologia , Ácidos Decanoicos/sangue , Adulto Jovem , Ácidos Graxos
3.
Toxics ; 12(3)2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38535908

RESUMO

Investigating the impact of urinary mercury and cadmium on anthropometric parameters in Korean children is crucial amid growing concerns about heavy metal exposure and childhood growth. Using data from the Korean National Environmental Health Survey (2015-2017), we assessed age- and sex-specific associations of urinary mercury and cadmium with height and body mass index (BMI) z-scores in 1458 children aged 3-5 (n = 571) and 6-11 years (n = 887). Overall, 5.0% had stunted height (3-5 years: 6.9%, 6-11 years: 3.8%), whereas older children exhibited higher overweight/obesity prevalence (29.2%) than younger ones did (22.2%). In 3-5-year-old boys, urinary mercury correlated negatively with height z-scores (p < 0.001), whereas in girls, urinary cadmium correlated positively (p = 0.015). Boys aged 6-11 years showed positive associations between mercury/cadmium levels and BMI z-scores (p = 0.012). Logistic regression indicated associations between urinary mercury and stunted height likelihood (p = 0.001) and between urinary cadmium and reduced overweight likelihood (p = 0.039) in 3-5-year-old boys. In boys aged 6-11 years, urinary cadmium levels were positively associated with overweight likelihood (p = 0.003). This study underscores the link between elevated urinary mercury, cadmium levels, and growth disruptions in Korean children, emphasizing the need for public health strategies for reducing childhood heavy metal exposure.

4.
Korean J Physiol Pharmacol ; 28(2): 165-181, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38414399

RESUMO

The slow and regular pacemaking activity of midbrain dopamine (DA) neurons requires proper spatial organization of the excitable elements between the soma and dendritic compartments, but the somatodendritic organization is not clear. Here, we show that the dynamic interaction between the soma and multiple proximal dendritic compartments (PDCs) generates the slow pacemaking activity in DA neurons. In multipolar DA neurons, spontaneous action potentials (sAPs) consistently originate from the axon-bearing dendrite. However, when the axon initial segment was disabled, sAPs emerge randomly from various primary PDCs, indicating that multiple PDCs drive pacemaking. Ca2+ measurements and local stimulation/perturbation experiments suggest that the soma serves as a stably-oscillating inertial compartment, while multiple PDCs exhibit stochastic fluctuations and high excitability. Despite the stochastic and excitable nature of PDCs, their activities are balanced by the large centrally-connected inertial soma, resulting in the slow synchronized pacemaking rhythm. Furthermore, our electrophysiological experiments indicate that the soma and PDCs, with distinct characteristics, play different roles in glutamate- induced burst-pause firing patterns. Excitable PDCs mediate excitatory burst responses to glutamate, while the large inertial soma determines inhibitory pause responses to glutamate. Therefore, we could conclude that this somatodendritic organization serves as a common foundation for both pacemaker activity and evoked firing patterns in midbrain DA neurons.

5.
Braz. j. otorhinolaryngol. (Impr.) ; 83(6): 683-690, Nov.-Dec. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889335

RESUMO

Abstract Introduction: Auricular Arteriovenous Malformation of the external ear is a rarely encountered disease; in particular, arteriovenous malformation arising from the auricle, with spontaneous bleeding, has seldom been reported. Objective: In the current study, we report an unusual case of late-onset auricular arteriovenous malformation originating from the posterior auricular artery that was confirmed by computed tomographic angiography. The case was successfully managed by pre-surgical intravascular embolization followed by total lesion excision. Prompted by this case, we also present a scoping review of the literature. Methods: A case of a 60 year-old man with right auricular arteriovenous malformation treated in our tertiary care center, and 52 patients with auricular arteriovenous malformation described in 10 case reports and a retrospective review are presented. Auricular arteriovenous malformation can manifest as swelling of the ear, pulsatile tinnitus, pain, and/or bleeding. On physical examination, a pulsatile swelling and/or a tender mass is evident. When arteriovenous malformation is suspected, the lesions should be visualized using imaging modalities that optimally detect vascular lesions, and managed via embolization, mass excision, or auricular resection. Effectiveness of the various diagnostic methods used and the treatment outcomes were analyzed. Results: Various imaging modalities including Doppler sonography, computed tomographic angiography, magnetic resonance angiography, and/or transfemoral cerebral angiography were used to diagnose 38 cases reported in the literature. In another 15 cases, no imaging was performed; treatment was determined solely by physical examination and auscultation. Of the total of 53 cases, 12 were not treated (their symptoms were merely observed) whereas 20 underwent therapeutic embolization. In total, 32 patients, including 1 patient who was not treated and 10 with persistent or aggravated arteriovenous malformation after previous embolization, underwent mass excision or auricular resection depending on the extent of the lesion. No major postoperative complication was recorded. The postoperative follow-up duration varied from 1 month to 19 years, and only one case of unresectable, residual cervicofacial arteriovenous malformation was recorded. Conclusion: Auricular arteriovenous malformation is a rarely encountered disease, but should be suspected if a patient presents with a swollen ear and pulsatile tinnitus. Appropriate imaging is essential for diagnosis and evaluation of the extent of disease. As embolization affords only relatively poor control, total surgical removal of the vascular mass is recommended.


Resumo Introdução: Malformação Arteriovenosa Auricular da orelha externa é uma doença raramente observada, em particular, na região da aurícula, com hemorragia espontânea, tem sido infrequentemente relatada. Objetivo: No presente estudo, relatamos um caso incomum de malformação arteriovenosa auricular de início tardio originária da artéria auricular posterior confirmada por angiotomografia computadorizada. O caso foi controlado com sucesso por embolização endovascular pré-cirúrgica seguida por excisão completa da lesão. Além disso, nós também apresentamos uma revisão abrangente da literatura. Método: Um homem de 60 anos de idade com malformação arteriovenosa auricular direita tratado em nosso centro de atendimento terciário e 52 pacientes com malformação arteriovenosa auricular descritos em 10 relatos de casos e um estudo de revisão são apresentados. A malformação arteriovenosa auricular pode manifestar-se como inchaço da orelha, zumbido pulsátil, dor e/ou sangramento. Ao exame físico, um edema pulsátil e/ou uma massa sensível é evidente. Quando há suspeita de malformação arteriovenosa, as lesões devem ser visualizadas usando modalidades de imagem que detectam de maneira ideal as lesões vasculares, e tratadas por meio de embolização, excisão total da lesão, ou ressecção auricular. A eficácia dos vários métodos de diagnóstico utilizados e os desfechos do tratamento foram analisados. Resultados: Várias modalidades de imagem, incluindo ultrassonografia Doppler, angiotomografia computadorizada, angiografia por ressonância magnética e/ou angiografia cerebral transfemoral foram usadas para diagnosticar 38 casos relatados na literatura. Em outros 15 casos, nenhuma imagem foi realizada; o tratamento foi determinado unicamente pelo exame físico e ausculta. Do total de 53 casos, 12 não foram tratados (os seus sintomas foram apenas observados), enquanto que 20 foram submetidos a embolização terapêutica. No total, 32 doentes, incluindo um paciente que não foi tratado e 10 com malformação arteriovenosa persistente ou agravada após a embolização anterior, foram submetidos a excisão completa da lesão ou ressecção auricular, dependendo da extensão da lesão. Nenhuma complicação pós-operatória importante foi registrada. O tempo de seguimento pós-operatório variou de 1 mês a 19 anos, e apenas um caso de malformação arteriovenosa cervicofacial irressecável, residual foi registrado. Conclusão: A malformação arteriovenosa auricular é uma doença raramente encontrada, mas deve ser suspeitada se um paciente apresentar orelha inchada e zumbido pulsátil. A imagem apropriada é essencial para o diagnóstico e avaliação da extensão da doença. Como a embolização proporciona apenas um controle relativamente precário, a remoção cirúrgica total da lesão vascular é recomendada.


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Malformações Arteriovenosas/patologia , Malformações Arteriovenosas/terapia , Pavilhão Auricular/anormalidades , Pavilhão Auricular/irrigação sanguínea , Estudos Retrospectivos , Resultado do Tratamento , Diagnóstico Diferencial , Embolização Terapêutica , Pavilhão Auricular/patologia , Angiografia por Tomografia Computadorizada
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