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1.
Biol Psychiatry Glob Open Sci ; 4(5): 100356, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-39205794

RÉSUMÉ

Background: Inflammation has been postulated as a mediating factor in the development of Alzheimer's disease (AD) pathology. We investigated candidate inflammatory markers related to conversion to AD among patients with depression. Methods: A longitudinal study was conducted with older women with depression who were at least 55 years of age, with a mean follow-up period of 5.73 years. At baseline, 9 inflammatory cytokines were measured using the immunoreactivity method. During follow-up, patients with depression who complained of cognitive impairment were evaluated and diagnosed with AD conversion. Association of the cytokines with conversion to AD was analyzed using multivariable Cox proportional hazards regression with adjusting covariates. For clinical applicability, the optimal cutoff value was determined using the minimum p value approach for the conversion to AD and was used to plot an AD-free survival curve. Results: Among 132 participants, 34 patients with depression (25.76%) developed AD during their follow-up period. Higher levels of interleukin (IL) 1ß at baseline (hazard ratio = 3.30 [95% CI, 1.11-9.78], p = .031) and lower levels of IL-10 (p < .001) were significantly associated with an increased risk of progression to AD. The survival curve plotted by the cutoff value of ≥0.25 pg/mL for IL-1ß and ≤0.15 pg/mL for IL-10 suggested adjusted hazard ratios of 8.96 (95% CI, 3.48-23.09; p < .001) for IL-1ß and 10.99 (p < .001) for IL-10, respectively. Conclusions: This study demonstrated that IL-1ß and IL-10 were associated with conversion to AD among patients with late-life depression, suggesting their potential as predictive markers of the transition to AD from depression.


Many patients with depression, more than expected, have been observed to be converted to Alzheimer's disease (AD) in the real world. We investigated potential inflammatory blood surrogate markers regarding progression from depression in late life to AD in 132 older Korean women with depression over a period of 1 to 18 years. Higher levels of the proinflammatory cytokine IL-1ß and lower levels of the anti-inflammatory cytokine IL-10 were associated with a higher risk of transition from depression to AD. These findings suggest that these markers could serve to predict the onset of AD in individuals with depression.

2.
ACS Chem Neurosci ; 15(3): 447-455, 2024 02 07.
Article de Anglais | MEDLINE | ID: mdl-38241020

RÉSUMÉ

Parkin interacting substrate (PARIS) is a pivotal transcriptional regulator in the brain that orchestrates the activity of various enzymes through its intricate interactions with biomolecules, including nucleic acids. Notably, the binding of PARIS to insulin response sequences (IRSs) triggers a cascade of events that results in the functional loss in the substantia nigra, which impairs dopamine release and, subsequently, exacerbates the relentless neurodegeneration. Here, we report the details of the interactions of PARIS with IRSs via classical zinc finger (ZF) domains in PARIS, namely, PARIS(ZF2-4). Our biophysical studies with purified PARIS(ZF2-4) elucidated the binding partner of PARIS, which generates specific interactions with the IRS1 (5'-TATTTTT, Kd = 38.9 ± 2.4 nM) that is positioned in the promoter region of peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α). Mutational and metal-substitution studies demonstrated that Zn(II)-PARIS(ZF2-4) could recognize its binding partner selectively. Overall, our work provides submolecular details regarding PARIS and shows that it is a transcriptional factor that regulates dopamine release. Thus, PARIS could be a crucial target for therapeutic applications.


Sujet(s)
Maladie de Parkinson , Protéines de répression , Humains , Protéines de répression/métabolisme , Dopamine/métabolisme , Maladie de Parkinson/métabolisme , Ubiquitin-protein ligases/métabolisme , Facteurs de transcription/métabolisme
3.
BMC Plant Biol ; 23(1): 281, 2023 May 26.
Article de Anglais | MEDLINE | ID: mdl-37237253

RÉSUMÉ

BACKGROUND: Leaf explants are major materials in plant tissue cultures. Incubation of detached leaves on phytohormone-containing media, which is an important process for producing calli and regenerating plants, change their cell fate. Although hormone signaling pathways related to cell fate transition have been widely studied, other molecular and physiological events occurring in leaf explants during this process remain largely unexplored. RESULTS: Here, we identified that ethylene signals modulate expression of pathogen resistance genes and anthocyanin accumulation in leaf explants, affecting their survival during culture. Anthocyanins accumulated in leaf explants, but were not observed near the wound site. Ethylene signaling mutant analysis revealed that ethylene signals are active and block anthocyanin accumulation in the wound site. Moreover, expression of defense-related genes increased, particularly near the wound site, implying that ethylene induces defense responses possibly by blocking pathogenesis via wounding. We also found that anthocyanin accumulation in non-wounded regions is required for drought resistance in leaf explants. CONCLUSIONS: Our study revealed the key roles of ethylene in the regulation of defense gene expression and anthocyanin biosynthesis in leaf explants. Our results suggest a survival strategy of detached leaves, which can be applied to improve the longevity of explants during tissue culture.


Sujet(s)
Arabidopsis , Arabidopsis/génétique , Arabidopsis/métabolisme , Anthocyanes/métabolisme , Éthylènes/métabolisme , Feuilles de plante/métabolisme , Régulation de l'expression des gènes végétaux
4.
J Microbiol Biotechnol ; 32(3): 287-293, 2022 Mar 28.
Article de Anglais | MEDLINE | ID: mdl-35131957

RÉSUMÉ

The hydroxylation of methane (CH4) is crucial to the field of environmental microbiology, owing to the heat capacity of methane, which is much higher than that of carbon dioxide (CO2). Soluble methane monooxygenase (sMMO), a member of the bacterial multicomponent monooxygenase (BMM) superfamily, is essential for the hydroxylation of specific substrates, including hydroxylase (MMOH), regulatory component (MMOB), and reductase (MMOR). The diiron active site positioned in the MMOH α-subunit is reduced through the interaction of MMOR in the catalytic cycle. The electron transfer pathway, however, is not yet fully understood due to the absence of complex structures with reductases. A type II methanotroph, Methylosinus sporium 5, successfully expressed sMMO and hydroxylase, which were purified for the study of the mechanisms. Studies on the MMOH-MMOB interaction have demonstrated that Tyr76 and Trp78 induce hydrophobic interactions through π-π stacking. Structural analysis and sequencing of the ferredoxin domain in MMOR (MMOR-Fd) suggested that Tyr93 and Tyr95 could be key residues for electron transfer. Mutational studies of these residues have shown that the concentrations of flavin adenine dinucleotide (FAD) and iron ions are changed. The measurements of dissociation constants (Kds) between hydroxylase and mutated reductases confirmed that the binding affinities were not significantly changed, although the specific enzyme activities were significantly reduced by MMOR-Y93A. This result shows that Tyr93 could be a crucial residue for the electron transfer route at the interface between hydroxylase and reductase.


Sujet(s)
Électrons , Mixed function oxygenases , Transport d'électrons , Méthane , Mixed function oxygenases/métabolisme , Oxygénases/composition chimique , Oxygénases/génétique
5.
Article de Anglais | MEDLINE | ID: mdl-36612405

RÉSUMÉ

This study aimed to examine the effectiveness of a discharge plan model for South Korean patients with cancer who had completed treatment and were returning to the community. Overall, 23 patients with cancer were recruited at the National Cancer Center in Goyang-si. The effectiveness of the discharge plan was examined using four methods: Social Needs Screening Toolkit (2018), early screening for discharge plan, current life situation v.2.0, and a questionnaire regarding problems after discharge from the hospital. Subsequently, the results were analyzed using descriptive statistical analysis methods with the Stata 14.0 program. The largest age group of study participants was between 45 and 64 years. No participants responded to urgent needs, whereas nine (39.13%) participants needed support for their social needs. According to the in-depth evaluation of participants, more than 80% of the respondents answered that patients with cancer needed no help in self-management, daily living activities, or mental health. The satisfaction survey results showed that the degree to which the "discharge plan" was helpful for health management at home after discharge was 4.41 of 5, and the degree to which it helped return to daily life was 3.86 of 5.


Sujet(s)
Tumeurs , Gestion de soi , Humains , Adulte d'âge moyen , Projets pilotes , Enquêtes et questionnaires , Activités de la vie quotidienne , Tumeurs/thérapie , République de Corée , Sortie du patient
6.
Dalton Trans ; 50(48): 17817-17831, 2021 Dec 14.
Article de Anglais | MEDLINE | ID: mdl-34806716

RÉSUMÉ

The binding ability of lectins has gained attention owing to the carbohydrate-specific interactions of these proteins. Such interactions can be applied to diverse fields of biotechnology, including the detection, isolation, and concentration of biological target molecules. The physiological aspects of the lectin concanavalin A (ConA) have been intensively studied through structural and functional investigations. X-ray crystallography studies have proven that ConA has two ß-sheets and a short α-helix and that it exists in the form of a metalloprotein containing Mn2+ and Ca2+. These heterometals are coordinated with side chains located in a metal-coordinated domain (MCD), and they affect the structural environment in the carbohydrate-binding domain (CBD), which interacts with carbohydrates through hydrogen bonds. Recent studies have shown that ConA can regulate biophysical interactions with glycoproteins in virus envelopes because it specifically interacts with diverse polysaccharides through its CBD (Tyr, Asn, Asp, and Arg residues positioned next to the MCD). Owing to their protein-protein interaction abilities, ConA can form diverse self-assembled complexes including monomers, dimers, trimers, and tetramers, thus affording unique results in different applications. In this regard, herein, we present a review of the structural modifications in ConA through metal-ion coordination and their effect on complex formation. In recent approaches, ConA has been applied for viral protein detection, on the basis of the interactions of ConA. These aspects indicate that lectins should be thoroughly investigated with respect to their biophysical interactions, for avoiding unexpected changes in their interaction abilities.


Sujet(s)
Calcium/métabolisme , Concanavaline A/métabolisme , Manganèse/métabolisme , Xénobiotique/métabolisme , Calcium/composition chimique , Concanavaline A/composition chimique , Cristallographie aux rayons X , Manganèse/composition chimique , Modèles moléculaires , Xénobiotique/composition chimique
7.
Dalton Trans ; 50(45): 16493-16498, 2021 Nov 23.
Article de Anglais | MEDLINE | ID: mdl-34734616

RÉSUMÉ

By facilitating electron transfer to the hydroxylase diiron center, MMOR-a reductase-serves as an essential component of the catalytic cycle of soluble methane monooxygenase. Here, the X-ray structure analysis of the FAD-binding domain of MMOR identified crucial residues and its influence on the catalytic cycle.


Sujet(s)
Flavine adénine dinucléotide/métabolisme , Methylosinus/métabolisme , Oxidoreductases/métabolisme , Sites de fixation , Catalyse , Cristallographie aux rayons X , Transport d'électrons , Flavine adénine dinucléotide/composition chimique , Methylosinus/enzymologie , Oxidoreductases/composition chimique , Oxygénases/métabolisme , Conformation des protéines , Domaines protéiques
8.
Org Biomol Chem ; 14(21): 4829-41, 2016 Jun 07.
Article de Anglais | MEDLINE | ID: mdl-27145715

RÉSUMÉ

Angiogenesis plays important roles in tumor growth and metastasis. Sunitinib (Sutent®) is an antitumor agent targeting receptor tyrosine kinases which are involved in angiogenesis as well as cancer cell growth and survival. Using the pyridin-3-ol scaffold, which was previously reported as an excellent antioxidant and antiangiogenic platform, we have synthesized sunitinib mimics 6 by hybridizing bicyclic pyridinol 4 as a key scaffold and pyrrole-2-carbaldehydes 7 as side chains. Cytotoxicity assays showed that compounds 6 have comparable to better anticancer activity than sunitinib against five different cancer cell lines. In addition, compounds 6 showed even lower levels of cytotoxicity against normal cells, resulting in up to 26-fold better safety windows, than sunitinib. Signaling pathway-associated transcription factor reporter assay and western blot analyses revealed that apoptosis induction in MDA-MB-231 human breast cancer cells by 6F is mainly mediated through the p53 increase and down-regulation of phospho-signal transducer and activator of transcription 3 (STAT3) and its target gene products, cyclin D, Bcl-2, and survivin. The data strongly suggest that our hybrid compounds can provide a novel anticancer scaffold with improved and safer cytotoxicity profiles than sunitinib.


Sujet(s)
Antinéoplasiques/synthèse chimique , Antinéoplasiques/pharmacologie , Indoles/synthèse chimique , Indoles/pharmacologie , Pyridines/composition chimique , Pyrroles/composition chimique , Animaux , Antinéoplasiques/composition chimique , Apoptose/effets des médicaments et des substances chimiques , Lignée cellulaire tumorale , Prolifération cellulaire/effets des médicaments et des substances chimiques , Techniques de chimie synthétique , Régulation négative/effets des médicaments et des substances chimiques , Conception de médicament , Humains , Indoles/composition chimique , Transport des protéines/effets des médicaments et des substances chimiques , Facteur de transcription STAT-3/métabolisme , Transduction du signal/effets des médicaments et des substances chimiques , Sunitinib , Protéine p53 suppresseur de tumeur/métabolisme
9.
Obstet Gynecol Sci ; 57(6): 471-7, 2014 Nov.
Article de Anglais | MEDLINE | ID: mdl-25469335

RÉSUMÉ

OBJECTIVE: To evaluate correlation of preoperative anemia with clinical outcomes in patients with early stage cervical cancer who were treated with radical hysterectomy and lymph node dissection. METHODS: Patients who underwent radical hysterectomy and lymph node dissection for cervical cancer from January 2001 to February 2012 were included in this study. Clinicopatholgoical factors included in univariate and multivariate analysis were age, tumor histology, FIGO (International Federation of Gyneocology and Obstetrics) stage, preoperative hemoglobin, depth of invasion, tumor size, parametrial involvement, resection margin, and lymph node status. RESULTS: A total of 387 patients were retrospectively analyzed in this study; 141 patients (36.4%) had preoperative anemia (hemoglobin <12 g/dL) and 16 out of 141 patients (11.3%) received blood transfusion for correction of preoperative anemia. Patients with preoperative anemia showed significant association with age <50 years, more advanced stage, non-squamous cell carcinoma histology, larger tumor size, deeper stromal invasion, and lymph node metastasis (P<0.05). Both relapse-free survival and overall survival were worse in patients with preoperative anemia in univariate analysis. In multivariate analysis, overall survival was worse in patients with preoperative anemia, but relapse-free survival was not associated with preoperative anemia. In the intergroup analysis of anemic patients for the effect of preoperative blood transfusion, preoperative anemia correction did not affect survival. CONCLUSION: Preoperative anemia was not an independent prognostic factor for survival in patients with early cervical cancer. However, it was associated with poor prognostic factors. Further study in large population is needed.

10.
Biochem Biophys Res Commun ; 451(2): 282-7, 2014 Aug 22.
Article de Anglais | MEDLINE | ID: mdl-25088993

RÉSUMÉ

Extracts of Prunella vulgaris have been shown to exert antiestrogenic effects. To identify the compounds responsible for these actions, we isolated the constituents of P. vulgaris and tested their individual antiestrogenic effects. Rosmarinic acid, caffeic acid, ursolic acid (UA), oleanolic acid, hyperoside, rutin and betulinic acid (BA) were isolated from the flower stalks of P. vulgaris var. lilacina Nakai (Labiatae). Among these constituents, UA and BA showed significant antiestrogenic effects, measured as a decrease in the mRNA level of GREB1, an estrogen-responsive protein; the effects of BA were stronger than those of UA. UA and BA were capable of suppressing estrogen response element (ERE)-dependent luciferase activity and expression of estrogen-responsive genes in response to exposure to estradiol, further supporting the suppressive role of these compounds in estrogen-induced signaling. However, neither UA nor BA was capable of suppressing estrogen signaling in cells ectopically overexpressing estrogen receptor α (ERα). Furthermore, both mRNA and protein levels of ERα were reduced by treatment with UA or BA, suggesting that UA and BA inhibit estrogen signaling by suppressing the expression of ERα. Interestingly, both compounds enhanced prostate-specific antigen promoter activity. Collectively, these findings demonstrate that UA and BA are responsible for the antiestrogenic effects of P. vulgaris and suggest their potential use as therapeutic agents against estrogen-dependent tumors.


Sujet(s)
Modulateurs des récepteurs des oestrogènes/pharmacologie , Récepteur alpha des oestrogènes/antagonistes et inhibiteurs , Récepteur alpha des oestrogènes/métabolisme , Oestrogènes/métabolisme , Triterpènes/pharmacologie , Tumeurs du sein/traitement médicamenteux , Tumeurs du sein/génétique , Tumeurs du sein/métabolisme , Lignée cellulaire tumorale , Évaluation préclinique de médicament , Modulateurs des récepteurs des oestrogènes/isolement et purification , Récepteur alpha des oestrogènes/génétique , Femelle , Humains , Cellules MCF-7 , Mâle , Protéines tumorales/génétique , Triterpènes pentacycliques , Phytothérapie , Plantes médicinales/composition chimique , Régions promotrices (génétique) , Antigène spécifique de la prostate/génétique , Tumeurs de la prostate/traitement médicamenteux , Tumeurs de la prostate/génétique , Tumeurs de la prostate/métabolisme , Prunella/composition chimique , ARN messager/génétique , ARN messager/métabolisme , ARN tumoral/génétique , ARN tumoral/métabolisme , Transduction du signal/effets des médicaments et des substances chimiques , Triterpènes/isolement et purification , Acide bétulinique , Ursolic Acid
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