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1.
Dev Cell ; 59(4): 545-557.e4, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38228139

RESUMO

Cyclin-dependent kinase (CDK) determines the temporal ordering of the cell cycle phases. However, despite significant progress in studying regulators of CDK and phosphorylation patterns of CDK substrates at the population level, it remains elusive how CDK regulators coordinately affect CDK activity at the single-cell level and how CDK controls the temporal order of cell cycle events. Here, we elucidate the dynamics of CDK activity in fission yeast and mammalian cells by developing a CDK activity biosensor, Eevee-spCDK. We find that although CDK activity does not necessarily correlate with cyclin levels, it converges to the same level around mitotic onset in several mutant backgrounds, including pom1Δ cells and wee1 or cdc25 overexpressing cells. These data provide direct evidence that cells enter the M phase when CDK activity reaches a high threshold, consistent with the quantitative model of cell cycle progression in fission yeast.


Assuntos
Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces , Animais , Fosforilação , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Mitose , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Mamíferos/metabolismo , Proteínas Tirosina Quinases/genética , Proteínas de Schizosaccharomyces pombe/genética , Proteínas de Schizosaccharomyces pombe/metabolismo
2.
ACS Chem Biol ; 18(12): 2506-2515, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37990966

RESUMO

Cells sense extracellular stimuli through membrane receptors and process information through an intracellular signaling network. Protein translocation triggers intracellular signaling, and techniques such as chemically induced dimerization (CID) have been used to manipulate signaling pathways by altering the subcellular localization of signaling molecules. However, in the fission yeast Schizosaccharomyces pombe, the commonly used FKBP-FRB system has technical limitations, and therefore, perturbation tools with low cytotoxicity and high temporal resolution are needed. We here applied our recently developed self-localizing ligand-induced protein translocation (SLIPT) system to S. pombe and successfully perturbed several cell cycle-related proteins. The SLIPT system utilizes self-localizing ligands to recruit binding partners to specific subcellular compartments such as the plasma membrane or nucleus. We optimized the self-localizing ligands to maintain the long-term recruitment of target molecules to the plasma membrane. By knocking in genes encoding the binding partners for self-localizing ligands, we observed changes in the localization of several endogenous molecules and found perturbations in the cell cycle and associated phenotypes. This study demonstrates the effectiveness of the SLIPT system as a chemogenetic tool for rapid perturbation of endogenous molecules in S. pombe, providing a valuable approach for studying intracellular signaling and cell cycle regulation with an improved temporal resolution.


Assuntos
Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Ligantes , Transporte Proteico , Proteínas de Ciclo Celular/metabolismo , Sistemas de Translocação de Proteínas/metabolismo , Proteínas de Schizosaccharomyces pombe/genética , Proteínas de Schizosaccharomyces pombe/metabolismo
3.
Environ Geochem Health ; 45(8): 5879-5891, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37179508

RESUMO

Fine atmospheric particles, such as PM2.5, are strongly related to the onset and exacerbation of inflammatory responses leading to the development of respiratory and cardiovascular diseases. PM2.5 is a complex mixture of tiny particles with different properties (i.e., size, morphology, and chemical components). Moreover, the mechanism by which PM2.5 induces inflammatory responses has not been fully elucidated. Therefore, it is necessary to determine the composition of PM2.5 to identify the main factors causing PM2.5-associated inflammation and diseases. In the present study, we investigated PM2.5 from two sites (Fukue, a remote monitoring site, and Kawasaki, an urban monitoring site) with greatly different environments and PM2.5 compositions. The results of ICP-MS and EDX-SEM indicated that PM2.5 from Kawasaki contained more metals and significantly induced the expression of the pro-inflammatory cytokine gene IL-8 compared to the PM2.5 from Fukue. We also verified the increased secretion of IL-8 protein from exposure to PM2.5 from Kawasaki. We further investigated their effects on inflammatory response and cytotoxicity using metal nanoparticles (Cu, Zn, and Ni) and ions and found that the Cu nanoparticles caused a dose-dependent increase in IL-8 expression together with significant cell death. We also found that Cu nanoparticles enhanced the secretion of IL-8 protein. These results suggest that Cu in PM2.5 is involved in lung inflammation.


Assuntos
Poluentes Atmosféricos , Material Particulado , Humanos , Material Particulado/toxicidade , Material Particulado/análise , Cobre/toxicidade , Cobre/metabolismo , Citocinas/análise , Citocinas/metabolismo , Citocinas/farmacologia , Células A549 , Interleucina-8/genética , Interleucina-8/metabolismo , Poluentes Atmosféricos/análise , Regulação para Cima , Pulmão
4.
Am J Pathol ; 193(3): 350-361, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36586479

RESUMO

Cancer antigen 125 (CA125) is one of the mucin family proteins and is a serum tumor marker for various tumors, such as ovarian cancer, endometrial cancer, pancreatic cancer, and bladder cancer. CA125 is used to distinguish between benign and malignant tumors, monitor the response to chemotherapy, and detect relapse after initial treatment. Recently, CA125 was reported to be involved in chemoresistance through the physical characteristics of mucin or by modifying the immune tumor-microenvironment. However, the relationship between CA125 expression and chemoresistance in bladder cancer is still unclear. In this study, the clinicopathologic features of bladder cancer with CA125 expression and the status of the tumor-microenvironment related to gemcitabine/cisplatin resistance were investigated using publicly available data sets (Cancer Genome Atlas Expression, GSE169455 data set) from the cBioPortal website, the National Center for Biotechnology Information website, and an in-house case collection of bladder cancer. The cases with CA125 expression had poorer disease-free and overall survival rates than those without CA125 expression. A mucinous area surrounding cancer cells was frequently detected in cases with CA125 expression (81%; 13/16 cases). CA125 expression was also related to the immunosuppressive tumor-microenvironment through the infiltration of immunosuppressive immune cells, such as regulatory T cells and M2 macrophages. These results suggest that the status of tumor-microenvironment associated with CA125 is involved in gemcitabine/cisplatin resistance in bladder cancer.


Assuntos
Antígeno Ca-125 , Cisplatino , Resistencia a Medicamentos Antineoplásicos , Gencitabina , Microambiente Tumoral , Neoplasias da Bexiga Urinária , Humanos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Antígeno Ca-125/genética , Antígeno Ca-125/metabolismo , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Gencitabina/farmacologia , Gencitabina/uso terapêutico , Mucinas/genética , Mucinas/metabolismo , Recidiva Local de Neoplasia , Microambiente Tumoral/genética , Microambiente Tumoral/fisiologia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Resistencia a Medicamentos Antineoplásicos/fisiologia
5.
Hinyokika Kiyo ; 68(10): 323-325, 2022 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-36329380

RESUMO

An inebriated 58-year-old woman with a history of hysterectomy presented to the emergency department with abdominal pain. The patient received hydration and acetaminophen, which led to symptom resolution. The patient returned with severe abdominal pain, 12 hours later. Computed tomography (CT) revealed a large volume of ascites and bladder wall disruption. Ascitic fluid analysis showed an elevated creatinine (Cre) level of 7.56 mg/dl, and the ascites to serum Cre ratio was 2.96, which indicated urinary ascites secondary to bladder rupture. The patient was diagnosed with intraperitoneal bladder rupture and underwent successful conservative treatment using an indwelling urinary catheter.


Assuntos
Doenças da Bexiga Urinária , Bexiga Urinária , Feminino , Humanos , Pessoa de Meia-Idade , Bexiga Urinária/diagnóstico por imagem , Líquido Ascítico , Ascite/diagnóstico por imagem , Ascite/etiologia , Ascite/terapia , Ruptura Espontânea/etiologia , Doenças da Bexiga Urinária/etiologia , Dor Abdominal/complicações , Ruptura
6.
Langmuir ; 38(1): 112-121, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-34967642

RESUMO

Liposomes, molecular self-assemblies resembling biological membranes, are a promising scaffold to investigate the physicochemical logic behind the complexity of living cells. Despite elaborate synthetic studies constructing cell-like chemical systems using liposomes, less attention has been paid to the proactive role of the membrane emerging as dynamics of the molecular self-assembly. This study investigated the liposomes containing anionic phospholipids by exposing them to steady flow conditions using a newly constructed automatic microfluidic observation platform. We demonstrated that the liposomes accumulated even macromolecules under the microfluidic condition without pore formation. By investigating the effect of composition of liposomes and visualizing negatively charged phospholipids upon the flow, we presumed that the external flow caused a compositional asymmetry of anionic phospholipids between the inner/outer leaflets, and the asymmetry enabled a rapid accumulation of those molecules against the concentration gradient. The current study opens new research interests regarding the nature of biological membranes under steady flow conditions.


Assuntos
Lipossomos , Água , Atenção , Membranas , Fosfolipídeos
7.
Int J Urol ; 29(1): 42-48, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34599531

RESUMO

OBJECTIVES: To develop a prediction tool based on physical findings and environmental conditions without utilizing color Doppler ultrasonography to guide non-urologists and patients' families in determining the testicular torsion possibility among patients with acute scrotal pain. METHODS: Overall, 110 consecutive patients aged ≤30 years with acute scrotal pain at Saitama Medical Center between 2012 and 2014 were retrospectively evaluated. Physical examination results, including scrotal inspection, palpation and gait observation, and environmental conditions at pain onset (time range and ambient temperature) were collected. Multivariate analysis identified significant and independent risk factors for testicular torsion, and a nomogram predicting testicular torsion was constructed. The model underwent prospective validation in an independent set of 123 consecutive patients admitted with acute scrotal pain to our institution between 2015 and 2017. RESULTS: Testicular torsion diagnosis rates were 27% (30/110) and 26% (32/123) in the training and validation cohorts, respectively. Logistic regression analysis showed four risk factors for developing testicular torsion: abnormal testicular position, walking difficulty, midnight to early morning onset and ambient temperature <15°C at pain onset. The constructed nomogram showed that the areas under the receiver operating characteristic curves were 0.92 and 0.84 for the training and validation cohorts, respectively. The calibration plot showed an acceptable fitness between the predicted probability and the observed rate of testicular torsion. CONCLUSIONS: A novel nomogram was developed solely based on physical findings and environmental conditions to predict testicular torsion in Japanese patients with acute scrotal pain.


Assuntos
Torção do Cordão Espermático , Humanos , Japão/epidemiologia , Masculino , Nomogramas , Dor , Exame Físico , Estudos Retrospectivos , Escroto/diagnóstico por imagem , Torção do Cordão Espermático/diagnóstico por imagem , Torção do Cordão Espermático/epidemiologia
8.
Chem Pharm Bull (Tokyo) ; 69(10): 947-952, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34602575

RESUMO

Closed bilayer membranes of amphiphiles in water, termed vesicles, represent one of the promising models of primitive cellular compartments. Herein, we reviewed studies on the design and construction of vesicle-based cell models capable of sequential growth and division and their underlying analysis methods. We discussed the potential contribution of these studies to the universal understanding of the chemical/physical logics behind the steady reproduction of cellular membranes.


Assuntos
Membrana Celular/metabolismo , Bicamadas Lipídicas/metabolismo , Membrana Celular/química , Humanos , Bicamadas Lipídicas/química , Água/química , Água/metabolismo
9.
ACS Omega ; 5(31): 19429-19436, 2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-32803036

RESUMO

For the construction of a chemical model of contemporary living cells, the so-called water-in-oil emulsion transfer (WOET) method has drawn much attention as one of the promising preparation protocols for cell-sized liposomes encapsulating macromolecules and even micrometer-sized colloidal particles in high yields. Combining the throughput and accuracy of the observation is the key to developing a synthetic approach based on the liposomes prepared by the WOET method. Recent advances in microfluidic technology can provide a solution. By means of surface modification of a poly(dimethylsiloxane)-type microfluidic device integrating size-sorting and trapping modules, here, we enabled a simultaneous direct observation of the liposomes with a narrow size distribution, which were prepared by the WOET method. As a demonstration, we evaluated the variance of encapsulation of polystyrene colloidal particles and water permeability of the cell-sized liposomes prepared by the WOET method in the device. Since the liposomes prepared by the WOET method are useful for constructing cell models with an easy protocol, the current system will lead to a critical development of not only supramolecular chemistry and soft matter physics but also synthetic biology.

10.
Front Microbiol ; 11: 97, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32117127

RESUMO

Streptococcus dysgalactiae subsp. equisimilis (SDSE) is an emerging human pathogen that causes severe invasive streptococcal diseases. Recent reports have shown that SDSE exhibits high pathogenicity with different mechanisms from that of Streptococcus pyogenes, although the two streptococci possess some common virulence factors such as streptolysin, streptokinase, and cell-binding proteins. To date, only a few studies have examined the variety of mechanisms expressing the pathogenicity of SDSE. Among nine SDSE clinical isolates sequenced in this study, we present in vitro and in vivo analyses of KNZ01 and KNZ03, whose emm and multilocus species types (MLSTs) are prevalent in Japan and other countries. For the comparison of pathogenicity, we also utilized the ATCC 12394 strain. The whole-genome analysis showed that KNZ03 and ATCC 12394 are categorized into an identical clonal complex by MLST and are phylogenetically close. However, the three strains exhibited different characteristics for pathogenicity in vitro; ATCC 12394 showed significant cytotoxicity to human keratinocytes and release of streptolysin O (SLO) compared to KNZ01 and KNZ03; KNZ03 exhibited significantly high hemolytic activity, but did not secrete SLO. KNZ01 and KNZ03 adhered to human keratinocytes at a higher rate than ATCC 12394; KNZ03 showed a higher rate of survival after a brief (30 min) incubation with human neutrophils compared to the other two strains; also, KNZ01 grew more rapidly in the presence of human serum. In vivo subcutaneous infection commonly resulted in ulcer formation in the three strains 7 days after infection. KNZ01-infected mice showed significant body weight loss 2 days after infection. Besides, on post-infection day 2, only KNZ01 remained in the cutaneous tissues of mice. Scanning electron microscopy analysis revealed that KNZ01 formed an extracellular structure (biofilm), which was probably composed of cell wall-anchoring proteins, in the presence of glucose and human serum. The extracellular structure of ATCC 12394 was also changed dramatically in response to culture conditions, whereas that of KNZ03 did not. Our study proposed that each SDSE strain possesses different virulence factors characteristics for mediating pathogenicity in humans.

12.
Commun Chem ; 3(1): 32, 2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36703378

RESUMO

In investigations of the emergence of protocells at the origin of life, repeatable and continuous supply of molecules and ions into the closed lipid bilayer membrane (liposome) is one of the fundamental challenges. Demonstrating an abiotic process to accumulate substances into preformed liposomes against the concentration gradient can provide a clue. Here we show that, without proteins, cell-sized liposomes under hydrodynamic environment repeatedly permeate small molecules and ions, including an analogue of adenosine triphosphate, even against the concentration gradient. The mechanism underlying this accumulation of the molecules and ions is shown to involve their unique partitioning at the liposomal membrane under forced external flow in a constrained space. This abiotic mechanism to accumulate substances inside of the liposomal compartment without light could provide an energetically up-hill process for protocells as a critical step toward the contemporary cells.

13.
Sci Rep ; 9(1): 165, 2019 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-30655551

RESUMO

The self-reproduction of supramolecular assemblies based on the synthesis and self-assembly of building blocks is a critical step towards the construction of chemical systems with autonomous, adaptive, and propagation properties. In this report, we demonstrate that giant vesicles can grow and produce daughter vesicles by synthesizing and incorporating phospholipids in situ from ad-hoc precursors. Our model involves acyl chain elongation via copper(I)-catalyzed azide-alkyne [3 + 2] cycloaddition reaction and the ensuing production of synthetic phospholipids to induce budding and division. In addition, the growth and budding of giant vesicles were compatible with the encapsulation and transfer of macromolecules as large as lambda phage DNA to the buds. This chemical system provides a useful model towards the implementation of cell-like compartments capable of propagation and transport of biological materials.

14.
Life (Basel) ; 8(4)2018 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-30384503

RESUMO

Experimental evolution in chemical models of cells could reveal the fundamental mechanisms of cells today. Various chemical cell models, water-in-oil emulsions, oil-on-water droplets, and vesicles have been constructed in order to conduct research on experimental evolution. In this review, firstly, recent studies with these candidate models are introduced and discussed with regards to the two hierarchical directions of experimental evolution (chemical evolution and evolution of a molecular self-assembly). Secondly, we suggest giant vesicles (GVs), which have diameters larger than 1 µm, as promising chemical cell models for studying experimental evolution. Thirdly, since technical difficulties still exist in conventional GV experiments, recent developments of microfluidic devices to deal with GVs are reviewed with regards to the realization of open-ended evolution in GVs. Finally, as a future perspective, we link the concept of messy chemistry to the promising, unexplored direction of experimental evolution in GVs.

15.
Eur J Radiol Open ; 5: 41-44, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29719857

RESUMO

Diffusion-weighted whole-body magnetic resonance imaging with background suppression (DWIBS) is increasingly used in cancer imaging. However, little is known about its usefulness in the management of metastatic seminoma, in which evaluation of the viability of postchemotherapy residual nodules is pivotal. To date, 2-18fluoro-deoxy-d-glucose positron emission tomography (FDG-PET) has been recommended for post-chemotherapeutic assessment. We describe a case of metastatic seminoma in a 27-year-old man in which the viability of post-chemotherapy residual nodules tested false-positive on FDG-PET, but true-negative on DWIBS. DWIBS may be a good alternative technique to evaluate post-chemotherapy seminoma, although further studies are required to determine its usefulness.

16.
Nihon Hinyokika Gakkai Zasshi ; 108(2): 96-100, 2017.
Artigo em Japonês | MEDLINE | ID: mdl-29669983

RESUMO

A 47-year-old woman was transferred to our hospital in June 2014 in hemorrhagic shock due to rupture of a huge right renal angiomyolipoma (AML). Selective right renal arterial embolization performed that same day reversed the shock immediately. Despite the huge abdominal tumor, the patient was discharged 2 weeks later after refusing any further treatment.Two weeks later she noticed the abdominal tumor growing. One month after discharge, she was readmitted due to dyspnea caused by restriction of her breathing by the growing tumor mass. A CT revealed a massive increase in tumor size with internal liquefaction, a thrombus in the left common iliac vein, and a 12 mm aneurysm in the right renal artery. The patient requested removal of the abdominal tumor since her ADL had deteriorated. We decided to perform a right nephrectomy with consideration of the left common iliac vein thrombus and right renal arterial aneurysm.As a precaution against pulmonary embolism in case the left common iliac vein thrombus dislodged, a retrievable inferior vena cava (IVC) filter was inserted before surgery. We were also concerned about possible rupture of the right renal aneurysm, so the right renal artery was embolized before surgery. After these procedures, a right nephrectomy was performed via a transperitoneal approach.The surgery was uneventful. The tumor weighed about 11 kg including 7,000 mL of bloody fluid. The IVC filter was removed the day after surgery, but the thrombus in the left common iliac vein remained, and an anticoagulant was started. Three months later, the thrombus had disappeared, and the anticoagulant was discontinued six months after surgery.According to the treatment guidelines for deep vein thrombosis, anticoagulants are the drugs of choice. IVC filters are seldom used to prevent pulmonary embolism. We initially administered an anticoagulant for the thrombus in the left iliac vein. However, an increase in abdominal tumor size suggested the drug had caused internal rebleeding and it had to be discontinued. Ultimately, we used a temporary retrievable IVC filter during the right nephrectomy with success.There is currently no consensus on when to use an IVC filter. Moreover, very little data exists on the use of an IVC filter during the perioperative period. Therefore, given the risk of potential thromboembolism, although we were able to use it successfully in our surgery, it should not be employed without a thorough benefit-risk assessment.

17.
Nihon Hinyokika Gakkai Zasshi ; 107(4): 233-238, 2016.
Artigo em Japonês | MEDLINE | ID: mdl-29070736

RESUMO

(Objectives) Testicular torsion (TT) is a socially and clinically important urological emergency condition because delayed diagnosis and treatment can lead to testicular loss. Although a possible association between TT and low ambient temperature has been argued, the clinical significance of the association has not been fully elucidated. We retrospectively collected acute scrotum cases and investigated the association between the risk of TT among acute scrotums and ambient temperatures on the day of onset. (Patients and methods) We studied 105 consecutive acute scrotum patients with suspected TT who underwent urgent surgical exploration between October 2004 and October 2014. The patients' age, residential area, time and date of onset, laboratory findings, and operative findings were collected from their medical records. Climate data, including daily mean ambient temperature (DMAT), diurnal temperature change (DTC), humidity, and atmospheric pressure at the time of onset, were obtained from the Japan Meteorological Agency website. The chi-square and Wilcoxon rank sum tests were used to evaluate statistical differences. Logistic regression analysis used to identify significant predictors of TT. (Results) The median age of the patients was 13 years (range, 1-43 years). The affected side was the right/left/bilateral side in 46/58/1 of the patients. Surgical exploration revealed TT in 67 patients. The remaining 38 non-TT patients included 12 with testicular appendage torsions, 12 with epididymal appendage torsions, 9 with epididymitis, 2 with orchitis, 2 with idiopathic hematomas, and 1 with allergic purpura. The median DMATs at the day of onset were 10.8°C (1.8-29.4°C) in the TT patients and 19.4°C (1.9-29.1°C) in the non-TT patients. The incidence of TT among the patients with acute scrotum explored surgically (TT incidence) in days with DMATs <15°C (80%) was significantly higher than that in days with DMATs ≥ 15°C (45%; p<0.001). During days with DMATs ≥15°C, the TT incidence in days with DTCs ≥10°C (62%) was significantly higher than that in days with DTCs <10°C (32%; p=0.037). Multivariate analysis revealed higher age (≥14), low serum C-reactive protein level (<0.5 ng/ml) and low DMAT (<15°C) were significant risk factor for TT in patients with acute scrotum undergoing surgery. (Conclusions) It should be noted that in this study, the onset of acute scrotum during days with low ambient temperatures or large DTCs was associated with a moderate to high possibility of TT.

18.
J Inorg Biochem ; 147: 93-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25912243

RESUMO

Evidence exists that supports the various physiological roles of vanadium compounds, although the amount of vanadium in our body is limited. This limited concentration in our body does not attract much attention of the biological chemists, although the fact is present; even in the 19th century, vanadium derivatives were used for the therapeutic reagents. In the middle of the 20th century, the main focus of vanadium chemistry is mainly on the chemical and material fields. After the first discovery of vanadium compounds expressing ATPase activity, oxidovanadium(IV) sulfate was reported to have insulin mimic activity. Additionally, because some vanadium compounds possess cellular toxicity, trials were also carried out to examine the possible use of vanadium compounds as cancer therapeutics. The application of vanadium complexes was extended in recent years especially in the 21st century. In this review, we briefly explain the historical background of vanadium chemistry and also summarize the physiological role of vanadium complexes mainly focusing on the synthesis and physiological role of peroxidovanadium compounds and their interactions with insulin signal transduction pathways.


Assuntos
Hipoglicemiantes/farmacologia , Transdução de Sinais , Vanadatos/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Humanos , Hipoglicemiantes/química , Insulina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Vanadatos/química
19.
Int J Mol Sci ; 14(2): 3639-55, 2013 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-23434662

RESUMO

R(+)-alpha lipoic acid (RALA) is one of the cofactors for mitochondrial enzymes and, therefore, plays a central role in energy metabolism. RALA is unstable when exposed to low pH or heat, and therefore, it is difficult to use enantiopure RALA as a pharma- and nutra-ceutical. In this study, we have aimed to stabilize RALA through complex formation with cyclodextrins (CDs). α-CD, ß-CD and γ-CD were used for the formation of these RALA-CD complexes. We confirmed the complex formation using differential scanning calorimetry and showed by using HPLC analysis that complexed RALA is more stable than free RALA when subjected to humidity and high temperature or acidic pH conditions. Scanning electron microscopy studies showed that the particle size and shape differed depending on the cyclodextrin used for complexation. Further, the complexes of CD and RALA showed a different particle size distribution pattern compared with that of CD itself or that of the physical mixture of RALA and CD.

20.
J Inorg Biochem ; 121: 66-76, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23353084

RESUMO

Although the physiological effects of peroxidovanadium(V) complexes (pVs) have been extensively investigated both in vitro and in vivo with regard to their pharmacological activity, such as insulin-mimetic and antitumor activities, the relationship between the chemical and pharmacological properties of pVs is still unclear. Rational drug design with pVs depends on a full understanding of this relationship. Toward this end, the current report evaluates the physiological effects of 13 pVs were evaluated bound to a variety of ligand. Six of these ligands are tripodal tetradentate ligands, one is a linear tetradentate ligand, one boasts two pendant groups, three are tridentate ligands, and two are alkoxido-bridging, dinucleating ligands. The cytotoxicities of these pVs could be classified into three groups: significantly toxic, moderately toxic, and non- or negligibly toxic. Further, IC50 values could be related with the LMCT transition energies of the peroxido group, particularly among complexes with similar ligands. This relation indicates that the electronic properties of the peroxido group affected the physiological activity of the pV complex. We also investigated the insulin-signaling intensity of each pV. Phosphorylation of protein kinase B and extracellular signal-regulated kinase 1/2, two major insulin-signaling proteins, was observed after treating cells with pV for 30 min. Phosphorylation was particularly remarkable for complexes that exhibited high cytotoxicity. The present results demonstrate that the toxicity and physiological effects of pVs can be controlled by selecting an appropriate ancillary ligand. These findings provide a guide for synthesis of new pVs that may be used as candidate therapeutic agents.


Assuntos
Complexos de Coordenação/síntese química , Citotoxinas/síntese química , Elétrons , Peróxidos/síntese química , Compostos de Vanádio/síntese química , Animais , Linhagem Celular Tumoral , Complexos de Coordenação/farmacologia , Citotoxinas/farmacologia , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Insulina/metabolismo , Insulina/farmacologia , Ligantes , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Peróxidos/farmacologia , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade , Compostos de Vanádio/farmacologia
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