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1.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-1043796

RESUMO

Objectives@#Genetic factors are a major cause of osteoporosis. The present study evaluated the association of the apolipoprotein E (ApoE) genotype with bone mineral density (BMD) and its response to menopausal hormone therapy (MHT) in postmenopausal Korean women. @*Methods@#This retrospective cohort study included 172 postmenopausal women with no endocrine diseases, medications, or lifestyles that would affect bone metabolism and who were continuously treated with MHT for at least 2 years. BMDs were measured at baseline and periodically. @*Results@#Linear regression analysis demonstrated similar baseline BMDs at the lumbar spine, but significantly lower at the femur neck and total hip in the ApoE ε4 carrier than in the noncarrier group, after controlling for age, body mass index, and history of MHT usage. Overall, the Wilcoxon signed rank test demonstrated that MHT increased the BMD percentage change at all three regions, and the Generalized Estimating Equation (GEE) demonstrated significant time trends at the lumbar spine and femur neck. ApoE ε4 noncarriers exhibited a significant time trend in BMD changes at the femur neck, whereas ε4 carriers exhibited a time trend at the lumbar spine. However, BMD changes at each time point were comparable at all regions between the groups. Notably, GEE adjusted for baseline characteristics and BMD revealed a significant interaction effect of time and ApoE ε4 allele in BMD changes at the femur neck. @*Conclusions@#Postmenopausal Korean women carrying the ApoE ε4 allele demonstrated a lower hip BMD compared with ε4 noncarriers. Furthermore, the ε4 allele may modulate hip BMD responses to MHT.

2.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-926073

RESUMO

Objectives@#A retrospective cohort study was conducted to evaluate the effects of combination oral contraceptives (COCs) on bone mineral density (BMD) and metabolism in perimenopausal Korean women. @*Methods@#The study subjects comprised two groups. The COC group included 55 women who took low-dose COC for at least one year to control vasomotor symptoms. Another 55 women who had annual checkups without history of COC use served as controls. BMD and bone turnover markers were assessed periodically. @*Results@#In the control group, 12-month BMD values at the lumbar spine (LS) and total hip (TH) significantly decreased with a greater magnitude at LS, and bone resorption (BR) and formation (BF) markers increased concurrently with a larger change in BR. COCs increased BMD at LS after 12 months and prevented BMD decline at TH. Multivariable linear regression revealed a significant difference in LS BMD between groups at 12 months. In the COC group, there were significant negative correlations between baseline BMD and Z-score at LS and corresponding changes at 12 months. COCs did not alter BR markers, whereas BF markers were significantly decreased at 3 months. Group comparison at 12 months, as tested with adjusted linear regression, disclosed significant differences in both BR and BF makers. @*Conclusions@#Bone loss associated with activated bone turnover is evident during the menopausal transition, and COCs might prevent BMD decrease and suppress bone turnover markers in perimenopausal Korean women. Significant increase in LS BMD and decreases in BF makers suggest underlying mechanisms of greater impact on BF.

3.
Toxins (Basel) ; 13(9)2021 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-34564636

RESUMO

Whooping cough is a severe, highly contagious disease of the human respiratory tract, caused by Bordetellapertussis. The pathogenicity requires several virulence factors, including pertussis toxin (PTX), a key component of current available vaccines. Current vaccines do not induce mucosal immunity. Tissue-resident memory T cells (Trm) are among the first lines of defense against invading pathogens and are involved in long-term protection. However, the factors involved in Trm establishment remain unknown. Comparing two B.pertussis strains expressing PTX (WT) or not (ΔPTX), we show that the toxin is required to generate both lung CD4+ and CD8+ Trm. Co-administering purified PTX with ΔPTX is sufficient to generate these Trm subsets. Importantly, adoptive transfer of lung CD4+ or CD8+ Trm conferred protection against B. pertussis in naïve mice. Taken together, our data demonstrate for the first time a critical role for PTX in the induction of mucosal long-term protection against B. pertussis.


Assuntos
Bordetella pertussis/imunologia , Imunidade nas Mucosas , Pulmão/imunologia , Células T de Memória/imunologia , Toxina Pertussis/imunologia , Vacina contra Coqueluche/imunologia , Coqueluche/prevenção & controle , Animais , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Coqueluche/imunologia
4.
Mov Disord ; 35(5): 868-876, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32039503

RESUMO

BACKGROUND: SNCA multiplication is a genomic cause of familial PD, showing dosage-dependent toxicity. Until now, nonallelic homologous recombination was suggested as the mechanism of SNCA duplication, based on various types of repetitive elements found in the spanning region of the breakpoints. However, the sequence at the breakpoint was analyzed only for 1 case. OBJECTIVES: We have analyzed the breakpoint sequences of 6 patients with PD who had duplicated SNCA using whole-genome sequencing data to elucidate the mechanism of SNCA duplication. METHODS: Six patient samples with SNCA duplication underwent whole-genome sequencing. The duplicated regions were defined with nucleotide-resolution breakpoints, which were confirmed by junction polymerase chain reaction and Sanger sequencing. The search for potential non-B DNA-forming sequences and stem-loop structure predictions was conducted. RESULTS: Duplicated regions ranged from the smallest region of 718.3 kb to the largest one of 4,162 kb. Repetitive elements were found at 8 of the 12 breakpoint sequences on each side of the junction, but none of the pairs shared overt homologies. Five of these six junctions had microhomologies (2-4 bp) at the breakpoint, and a short stretch of sequences was inserted in 3 cases. All except one junction were located within or next to stem-loop structures. CONCLUSION: Our study has determined that homologous recombination mechanisms involving repetitive elements are not the main cause of the duplication of SNCA. The presence of microhomology at the junctions and their position within stem-loop structures suggest that replication-based rearrangements may be a common mechanism for SNCA amplification. © 2020 International Parkinson and Movement Disorder Society.


Assuntos
Duplicação Gênica , Rearranjo Gênico , Doença de Parkinson , alfa-Sinucleína/genética , Humanos , Doença de Parkinson/genética
5.
Artigo em 0 | WPRIM (Pacífico Ocidental) | ID: wpr-836116

RESUMO

Objectives@#When administered soon after menopause, hormone therapy can prevent coronary heart diseases in women. To explore the mechanism underlying the cardioprotective actions of estrogen, we investigated the effects of 17β-estradiol (17β-E2) on the plasminogen activator system using cultured vascular smooth muscle cells (VSMCs). @*Methods@#VSMCs were isolated from rat aortas. Protein expression of plasminogen activator inhibitor type 1 (PAI-1) and tissue-type plasminogen activator (t-PA) were evaluated using Western blotting and enzyme-linked immunosorbent assay, respectively. The enzyme activity of PAI-1 in a conditioned medium was assessed via reverse fibrin overlay zymography and that of t-PA was assessed via fibrin overlay zymography. Gene expression was quantified using real-time reverse transcription-polymerase chain reaction. @*Results@#Following pre-treatment for 24 hours, 17β-E2 suppressed both protein expression and enzyme activity of PAI-1 stimulated by lysophosphatidylcholine (lysoPC) in a significant and dose-dependent manner at a near physiological concentration. Moreover, 17β-E2 (10−7 M) inhibited PAI-1 gene expression, and ICI 182,780—a specific estrogen receptor antagonist—blocked the effects of 17β-E2 on the PAI-1 protein. 17β-E2 did not affect t-PA secretion but significantly enhanced free t-PA activity through reduced binding to PAI-1. Furthermore, 17β-E2 suppressed intracellular reactive oxygen species production and nuclear factor-κB-mediated transcription. @*Conclusions@#In VSMCs stimulated with lysoPC, 17β-E2 reduced PAI-1 expression through a non-receptor-mediated mechanism via antioxidant activity as well as a receptor-mediated mechanism; however, it did not alter t-PA secretion. Of note, 17β-E2 suppressed PAI- 1 activity and concurrently enhanced t-PA activity, suggesting a beneficial influence on fibrinolysis.

6.
Artigo em 0 | WPRIM (Pacífico Ocidental) | ID: wpr-836117

RESUMO

Objectives@#Coronary heart disease (CHD) risk increases in women after menopause, but menopausal hormone therapy (MHT) helps prevent CHD if started early after menopause. To explore the mechanism underlying the direct vascular actions of estrogen, the effects of 17β-estradiol (E2) on apoptosis of vascular smooth muscle cells (VSMCs) induced with lysophosphatidylcholine (lysoPC), an active component of oxidized low-density lipoprotein, were investigated in the present study. @*Methods@#VSMCs were isolated from rat aortas. Apoptosis and protein expression of caspases were assessed using propidium iodide staining and Western blot analysis, respectively. Intracellular formation of reactive oxygen species (ROS) was examined using dichlorofluorescein diacetate, a cell-permeable oxidation-sensitive probe, and quantitated with flow cytometry. Nuclear factor-κB (NF-κB) activation was determined after transfection with a reporter plasmid containing the luciferase reporter gene. @*Results@#After pre-treatment for 24 hours, 17β-E2 suppressed lysoPC-induced (15 mM) apoptotic cell death in a dose-dependent manner with statistical significance at near physiological concentration. 17β-E2 (10−6 M) also increased protein levels of caspase-9 and -8 precursors and decreased the active form of caspase-3. Western blot analysis using subcellular fractions showed that 17β-E2 decreased mitochondrial Bax levels and concomitantly increased cytosolic Bax expression. Furthermore, intracellular production of ROS and NF- κB-mediated transcriptional activity were reduced with 17β-E2. In addition, estrogen effects on apoptosis were partially blocked by ICI 182,780, a specific estrogen receptor antagonist. @*Conclusions@#In cultured VSMCs treated with lysoPC, 17β-E2 reduced apoptotic cell death by down-regulating both extrinsic and intrinsic apoptosis pathways, contributing to the preventive action of MHT against CHD.

7.
Enzyme Microb Technol ; 126: 18-23, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31000160

RESUMO

A solvent-mediated method (SMM) was used to prepare supersaturated sugar solutions in hydrophobic and mixture of hydrophilic/hydrophobic ionic liquids (ILs), namely, [Bmim][Tf2N] and [Bmim][TfO]/[Bmim][Tf2N], respectively. In this method, sugars were first solubilized in a mixture of organic solvent and water (i.e. methanol:water, 1:1 v/v), and then added to [Bmim][Tf2N] and/or [Bmim][TfO]/[Bmim][Tf2N] mixture. Supersaturated sugar solution in ILs were obtained by removing organic solvents and water under vacuum evaporation. Sugar solubilities in ILs, especially in hydrophobic IL ([Bmim][Tf2N]) and in [Bmim][TfO]/[Bmim][Tf2N] mixture prepared by SMM were greater than in ILs prepared using water-mediated method (WMM), which suggested methanol aided sugar solvation in hydrophobic media. In addition, interactions between glucose molecules and between glucose and methanol, water, and IL were investigated by all-atom molecular dynamics (MD) simulation. The MD simulation results showed that initial water and water/methanol molecules around glucose were gradually replaced by IL anions. Notably, SMM resulted in stronger interaction between IL anions and glucose than WMM, which was attributed to greater solubility of sugar in ILs prepared by SMM. Resultantly, the productivity of lipase-catalyzed production of glucose laurate using supersaturated glucose solution in [Bmim][TfO]/[Bmim][Tf2N] mixture prepared by SMM was at least 1.76-fold greater than that obtained in IL mixture prepared by WMM.


Assuntos
Ésteres/síntese química , Ácidos Graxos/síntese química , Proteínas Fúngicas/metabolismo , Glucose/química , Líquidos Iônicos/química , Lipase/metabolismo , Catálise , Esterificação , Proteínas Fúngicas/química , Interações Hidrofóbicas e Hidrofílicas , Lipase/química , Simulação de Dinâmica Molecular , Solubilidade
8.
Ultrason Sonochem ; 53: 187-191, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30686599

RESUMO

Ionic liquids (ILs) have attracted much attention as promising alternatives for volatile organic solvents. Although the applications of ILs have been found in a diverse range of fields, there are a limited number of methods for the recovery of ILs so far. As an efficient separation method, therefore, ultrasonic atomization has been attempted to recover hydrophilic ILs, [Bmim][BF4], from ILs-water solution. In order to examine the separation characteristics of hydrophilic ILs-water solution, ultrasonic atomization of hydrophilic ILs-water solution was performed under various operating conditions such as initial ILs concentration, ultrasonic electric power, carrier gas flow rate, and operating temperature. The result showed that hydrophilic ILs recovery yield increased with a decrease in ultrasonic electric power, gas velocity, and temperature. As an increase in initial ILs concentration, however, higher ILs recovery yield was obtained. After 6 h of ultrasonic atomization of 50% (v/v) [Bmim][BF4]-water solution, 93.4% of initial ILs amount was recovered without any changes in their structure at ultrasonic power of 10 W, carrier gas flow of 5 L/min and temperature of 20 °C. It demonstrated that ultrasonic atomization could be used for the recovery of ILs from ILs-aqueous solution.

9.
Adv Biochem Eng Biotechnol ; 168: 105-132, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30488166

RESUMO

The use of whole-cell biocatalysis in ionic liquid (IL)-containing systems has attracted increasing attention in recent years. Compared to bioreactions catalyzed by isolated enzymes, the major advantage of using whole cells in biocatalytic processes is that the cells provide a natural intracellular environment for the enzymes to function with in situ cofactor regeneration. To date, the applications of whole-cell biocatalysis in IL-containing systems have focused on the production of valuable compounds, mainly through reduction, oxidation, hydrolysis, and transesterification reactions. The interaction mechanisms between the ILs and biocatalysts in whole-cell biocatalysis offer the possibility to effectively integrate ILs with biotransformation. This chapter discusses these interaction mechanisms between ILs and whole-cell catalysts. In addition, examples of whole-cell catalyzed reactions with ILs will also be discussed. Graphical Abstract.


Assuntos
Biocatálise , Células , Líquidos Iônicos , Biotransformação , Células/metabolismo , Líquidos Iônicos/química
10.
Artigo em Coreano | WPRIM (Pacífico Ocidental) | ID: wpr-916225

RESUMO

Menopausal hormone therapy (MHT) was widely used to improve quality of life by controlling menopausal symptoms, including vasomotor symptoms and urogenital atrophy. Furthermore, observational studies consistently reported beneficial effects of MHT on late problems of menopause, such as osteoporosis, coronary heart disease (CHD), and possibly dementia. However, circumstances changed abruptly after the 2002 publication of the first findings from the Women's Health Initiative (WHI) study, which was conducted in postmenopausal women (average age, 63 years) using conventional doses of conjugated equine estrogen (CEE) and medroxyprogesterone acetate. CEE with medroxyprogesterone acetate increased the risk of breast cancer and did not prevent CHD. However, CEE alone showed a tendency to decrease the risk of both breast cancer and CHD, with significant differences between the two therapies. A subgroup analysis by age and years since menopause led to a timing hypothesis regarding the effects of MHT on CHD. Indeed, CEE alone in women aged 50 to 59 significantly reduced CHD risk by 35% after 13 years of follow-up. In 2015, a Cochrane meta-analysis of MHT trials reported a 48% reduction in CHD, no change in stroke, and most importantly, a 30% decrease in total mortality in women with less than 10 years since menopause. Long-term follow-up of WHI participants confirmed beneficial impacts of CEE on breast cancer incidence and mortality. Further, fracture reduction in women with osteopenia was observed during the intervention phase of the WHI study. If initiated early after menopause, MHT could again be considered to improve menopause-related quality of life and decrease all-cause mortality.

11.
Korean Journal of Medicine ; : 485-494, 2019.
Artigo em Coreano | WPRIM (Pacífico Ocidental) | ID: wpr-938598

RESUMO

Acromegaly is a chronic disorder caused by excessive growth hormone (GH) secretion. In most cases, the excess GH originates from GH-producing pituitary adenomas. Surgery is the preferred first-line treatment for patients with acromegaly, but medical management is considered when the disease persists after surgery or in cases where patients refuse surgery or are poor candidates for surgery. Somatostatin analogues are commonly used to treat acromegaly. The Korean Endocrine Society and the Korean Neuroendocrine Study Group have developed a position statement for the use of somatostatin analogues in the medical treatment of acromegaly. This position statement is based on evidence from the current literature and expert opinions. In the case of discrepancies among expert opinions, the experts voted to determine the recommended approach.

12.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-786093

RESUMO

OBJECTIVES: We evaluated the effects of adding intravenous pamidronate to ongoing menopausal hormone therapy (MHT) on bone mineral density (BMD) in postmenopausal Korean women with low BMD.METHODS: This retrospective cohort study included 74 postmenopausal women who received MHT for at least 1 year and had a BMD T-score of less than −2.0. Maintaining the same MHT regimen, these women were divided into two groups: oral placebo group (n = 44) and a pamidronate group of patients with gastrointestinal discomfort (n = 30) who received 15–30 mg pamidronate intravenously every 3–12 months. BMD was reviewed at 12-month follow-up. Bone resorption markers in both groups, urinary deoxypyridinoline levels in the placebo group, and serum N-telopeptide of type I collagen in the pamidronate group were assessed at 6 and 12 months.RESULTS: At baseline, the body mass index (BMI), duration of previous MHT, and femur neck (FN) BMD differed between the groups. Within-group analysis revealed that BMD of the lumbar spine (LS) and total hip (TH) significantly increased in the placebo group, whereas those of the LS, FN, and TH increased in the pamidronate group. The increase in BMD of LS was significantly greater in the pamidronate group, after adjusting for BMI and duration of previous MHT (mean change: 3.7% vs. 6.2%; P < 0.001). There were no changes in bone resorption markers in either group.CONCLUSIONS: Adding intravenous pamidronate to ongoing MHT for 12 months might increase LS BMD in postmenopausal Korean women with low BMD.


Assuntos
Feminino , Humanos , Índice de Massa Corporal , Densidade Óssea , Reabsorção Óssea , Estudos de Coortes , Colágeno Tipo I , Colo do Fêmur , Seguimentos , Quadril , Terapia de Reposição Hormonal , Osteoporose , Pós-Menopausa , Estudos Retrospectivos , Coluna Vertebral
13.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-765758

RESUMO

OBJECTIVES: Inflammation is a major mechanism underlying coronary heart disease (CHD) and C-reactive protein (CRP) is a marker of inflammation. When administered soon after menopause, menopausal hormone therapy (MHT) prevents CHD. This study was conducted to examine the impact of estrogen by administration route on CRP in postmenopausal Korean women using micronized progesterone (MP4) for endometrial protection. METHODS: This retrospective cohort study included 129 healthy women without CHD risk factors. Eighty-nine women took oral estrogen (conjugated equine estrogen, 0.625 mg/day or equivalent), and 40 women applied a 1.5-mg/day 0.1% percutaneous estradiol gel. MP4 was added in 82 women with an intact uterus. The CRP level was measured at baseline and three and six months after initiation of MHT. RESULTS: The baseline characteristics were comparable between the MHT groups except current age and age at menopause. After controlling for age, menopausal age, body mass index, and basal CRP, no significant change in CRP was observed in the oral estrogen group (n = 29). Follow-up CRP levels were also similar to the baseline in the percutaneous estrogen group (n = 18). However, three-month CRP was significantly lower than six-month CRP, and there was a significant time trend within the percutaneous estrogen group. However, the group difference did not reach statistical significance. CRP also did not differ by addition of MP4 in either group. CONCLUSIONS: In postmenopausal Korean women, no change in CRP was observed with oral estrogen, while percutaneous estrogen might decrease CRP. The estrogenic impacts were not influenced by adding MP4.


Assuntos
Feminino , Humanos , Índice de Massa Corporal , Proteína C-Reativa , Estudos de Coortes , Doença das Coronárias , Vias de Administração de Medicamentos , Estradiol , Estrogênios , Seguimentos , Terapia de Reposição Hormonal , Inflamação , Menopausa , Pós-Menopausa , Progesterona , Estudos Retrospectivos , Fatores de Risco , Útero
14.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-739219

RESUMO

The Korean Endocrine Society (KES) published clinical practice guidelines for the treatment of acromegaly in 2011. Since then, the number of acromegaly cases, publications on studies addressing medical treatment of acromegaly, and demands for improvements in insurance coverage have been dramatically increasing. In 2017, the KES Committee of Health Insurance decided to publish a position statement regarding the use of somatostatin analogues in acromegaly. Accordingly, consensus opinions for the position statement were collected after intensive review of the relevant literature and discussions among experts affiliated with the KES, and the Korean Neuroendocrine Study Group. This position statement includes the characteristics, indications, dose, interval (including extended dose interval in case of lanreotide autogel), switching and preoperative use of somatostatin analogues in medical treatment of acromegaly. The recommended approach is based on the expert opinions in case of insufficient clinical evidence, and where discrepancies among the expert opinions were found, the experts voted to determine the recommended approach.


Assuntos
Acromegalia , Consenso , Prova Pericial , Cobertura do Seguro , Seguro Saúde , Octreotida , Somatostatina
15.
Artigo em Coreano | WPRIM (Pacífico Ocidental) | ID: wpr-766572

RESUMO

Menopausal hormone therapy (MHT) was widely used to improve quality of life by controlling menopausal symptoms, including vasomotor symptoms and urogenital atrophy. Furthermore, observational studies consistently reported beneficial effects of MHT on late problems of menopause, such as osteoporosis, coronary heart disease (CHD), and possibly dementia. However, circumstances changed abruptly after the 2002 publication of the first findings from the Women's Health Initiative (WHI) study, which was conducted in postmenopausal women (average age, 63 years) using conventional doses of conjugated equine estrogen (CEE) and medroxyprogesterone acetate. CEE with medroxyprogesterone acetate increased the risk of breast cancer and did not prevent CHD. However, CEE alone showed a tendency to decrease the risk of both breast cancer and CHD, with significant differences between the two therapies. A subgroup analysis by age and years since menopause led to a timing hypothesis regarding the effects of MHT on CHD. Indeed, CEE alone in women aged 50 to 59 significantly reduced CHD risk by 35% after 13 years of follow-up. In 2015, a Cochrane meta-analysis of MHT trials reported a 48% reduction in CHD, no change in stroke, and most importantly, a 30% decrease in total mortality in women with less than 10 years since menopause. Long-term follow-up of WHI participants confirmed beneficial impacts of CEE on breast cancer incidence and mortality. Further, fracture reduction in women with osteopenia was observed during the intervention phase of the WHI study. If initiated early after menopause, MHT could again be considered to improve menopause-related quality of life and decrease all-cause mortality.


Assuntos
Feminino , Humanos , Atrofia , Doenças Ósseas Metabólicas , Neoplasias da Mama , Doença das Coronárias , Demência , Estrogênios , Seguimentos , Incidência , Acetato de Medroxiprogesterona , Menopausa , Mortalidade , Osteoporose , Publicações , Qualidade de Vida , Medição de Risco , Acidente Vascular Cerebral , Saúde da Mulher
16.
Korean Journal of Medicine ; : 485-494, 2019.
Artigo em Coreano | WPRIM (Pacífico Ocidental) | ID: wpr-786308

RESUMO

Acromegaly is a chronic disorder caused by excessive growth hormone (GH) secretion. In most cases, the excess GH originates from GH-producing pituitary adenomas. Surgery is the preferred first-line treatment for patients with acromegaly, but medical management is considered when the disease persists after surgery or in cases where patients refuse surgery or are poor candidates for surgery. Somatostatin analogues are commonly used to treat acromegaly. The Korean Endocrine Society and the Korean Neuroendocrine Study Group have developed a position statement for the use of somatostatin analogues in the medical treatment of acromegaly. This position statement is based on evidence from the current literature and expert opinions. In the case of discrepancies among expert opinions, the experts voted to determine the recommended approach.


Assuntos
Humanos , Acromegalia , Prova Pericial , Hormônio do Crescimento , Octreotida , Neoplasias Hipofisárias , Somatostatina
18.
Enzyme Microb Technol ; 111: 67-73, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29421039

RESUMO

Synthesis of caffeic acid ester essentially requires an efficient esterification process to produce various kinds of medicinally important ester derivatives. In the present study, a comprehensive and comparative analysis of whole-cell catalyzed caffeic acid esters production in ionic liquids (ILs) media was performed. Olive oil induced mycelial mass of halotolerant Aspergillus niger (A.niger) EXF 4321 was freeze dried and used as a catalyst. To ensure maximum solubilization of caffeic acid for highest substrate loading several ILs were screened and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Emim][Tf2N]) was found to have the maximum solubility and favoured for enzymatic activity of freeze dried mycelia. The whole-cell catalyzed synthesis of caffeic acid phenethyl ester (CAPE) conditions were optimized and bioconversion up to 84% was achieved at a substrate molar ratio of 1:20 (caffeic acid:2-phenyl ethanol), 30°C for 12h. Results obtained during this study were encouraging and helpful to design a bioreactor system to produce caffeic acid derived esters.


Assuntos
Aspergillus niger/metabolismo , Ácidos Cafeicos/metabolismo , Álcool Feniletílico/análogos & derivados , Álcoois/química , Álcoois/metabolismo , Biocatálise , Reatores Biológicos/microbiologia , Esterificação , Proteínas Fúngicas/metabolismo , Líquidos Iônicos , Cinética , Lipase/metabolismo , Álcool Feniletílico/metabolismo , Solubilidade , Temperatura
20.
J Biol Chem ; 292(28): 11970-11979, 2017 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-28588027

RESUMO

An imbalance between oxidative stress and antioxidant activity plays an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD). Cigarette smoke, a major risk factor of COPD, induces cellular oxidative stress, but levels of antioxidants such as heme oxygenase-1 (HO-1) are reduced in individuals with severe COPD. In this study, we evaluated the molecular mechanism of reduced HO-1 expression in human bronchial epithelial cells. We found that cigarette smoke extract (CSE) increases HO-1 levels via activation of NFE2-related factor 2 (Nrf2). However, pretreating cells with the protease neutrophil elastase (NE) suppressed the CSE-induced expression of HO-1 mRNA and protein. NE also decreased the sirtuin 1 (SIRT1) level, but did not inhibit CSE-induced nuclear translocation and DNA-binding activity of Nrf2. Transfection of cells with a Myc/His-tagged SIRT1 expression vector completely blocked the NE-mediated suppression of HO-1 expression. We further noted that the NE-induced down-regulation of SIRT1 was not due to decreased transcription or proteasomal/lysosomal degradation or loss of solubility. Immunofluorescence staining revealed that NE enters the cell cytoplasm, and we observed that NE directly cleaved SIRT1 in vitro, indicating that SIRT1 levels are decreased via direct degradation by internalized NE. Of note, we observed decreased SIRT1 levels in NE-treated primary human bronchial epithelial cells and in lung homogenates from both smokers and patients with COPD. In conclusion, NE suppresses CSE-induced HO-1 expression by cleaving SIRT1. This finding indicates the importance of cross-talk between oxidative stress and protease responses in the pathogenesis of COPD.


Assuntos
Brônquios/efeitos dos fármacos , Heme Oxigenase-1/metabolismo , Elastase de Leucócito/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Mucosa Respiratória/efeitos dos fármacos , Sirtuína 1/metabolismo , Fumar/efeitos adversos , Transporte Ativo do Núcleo Celular , Biomarcadores/metabolismo , Brônquios/imunologia , Brônquios/metabolismo , Brônquios/patologia , Linhagem Celular , Células Cultivadas , Misturas Complexas/toxicidade , Regulação Enzimológica da Expressão Gênica , Heme Oxigenase-1/antagonistas & inibidores , Heme Oxigenase-1/química , Humanos , Fator 2 Relacionado a NF-E2/agonistas , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Estresse Oxidativo , Transporte Proteico , Proteólise , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/patologia , Proteínas Recombinantes de Fusão , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Mucosa Respiratória/imunologia , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia , Sirtuína 1/antagonistas & inibidores , Sirtuína 1/química , Sirtuína 1/genética , Fumaça/efeitos adversos , Fumaça/análise , Fumar/metabolismo , Fumar/patologia , Produtos do Tabaco/efeitos adversos , Produtos do Tabaco/análise
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