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1.
Commun Biol ; 7(1): 1313, 2024 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-39396070

RESUMEN

Global climate change poses challenges to agricultural production and food security. Assessing the adaptive capacity of crop wild relatives to future climate is important for protecting key germplasm resources and breeding new crops. We performed population genomics, genotype-environment association analyses, and genomic offset assessment of Chinese wild rice, Zizania latifolia, a crop wild relative and potential new grain crop, based on 168 individuals from 42 populations. We found two genetic lineages in Z. latifolia, corresponding to the south and north of its range, that diverged during the Late Pleistocene. We also identified lineage-specific positively selected genes associated with flower development and flowering, seed shattering, pathogen defense response and cold tolerance. We further found that populations from southeastern China are the most maladapted to future climate and should be prioritized for conservation. Our findings provide important clues for leveraging existing genetic diversity to identify important germplasm resources and create climate-resilient crops.


Asunto(s)
Cambio Climático , Poaceae , Poaceae/genética , Poaceae/fisiología , Poaceae/crecimiento & desarrollo , Adaptación Fisiológica/genética , Productos Agrícolas/genética , Productos Agrícolas/crecimiento & desarrollo , China , Variación Genética , Genoma de Planta
2.
BMC Med Inform Decis Mak ; 24(1): 251, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39251987

RESUMEN

OBJECTIVE: To analyze primary angle closure suspect (PACS) patients' anatomical characteristics of anterior chamber configuration, and to establish artificial intelligence (AI)-aided diagnostic system for PACS screening. METHODS: A total of 1668 scans of 839 patients were included in this cross-sectional study. The subjects were divided into two groups: PACS group and normal group. With anterior segment optical coherence tomography scans, the anatomical diversity between two groups was compared, and anterior segment structure features of PACS were extracted. Then, AI-aided diagnostic system was constructed, which based different algorithms such as classification and regression tree (CART), random forest (RF), logistic regression (LR), VGG-16 and Alexnet. Then the diagnostic efficiencies of different algorithms were evaluated, and compared with junior physicians and experienced ophthalmologists. RESULTS: RF [sensitivity (Se) = 0.84; specificity (Sp) = 0.92; positive predict value (PPV) = 0.82; negative predict value (NPV) = 0.95; area under the curve (AUC) = 0.90] and CART (Se = 0.76, Sp = 0.93, PPV = 0.85, NPV = 0.92, AUC = 0.90) showed better performance than LR (Se = 0.68, Sp = 0.91, PPV = 0.79, NPV = 0.90, AUC = 0.86). In convolutional neural networks (CNN), Alexnet (Se = 0.83, Sp = 0.95, PPV = 0.92, NPV = 0.87, AUC = 0.85) was better than VGG-16 (Se = 0.84, Sp = 0.90, PPV = 0.85, NPV = 0.90, AUC = 0.79). The performance of 2 CNN algorithms was better than 5 junior physicians, and the mean value of diagnostic indicators of 2 CNN algorithm was similar to experienced ophthalmologists. CONCLUSION: PACS patients have distinct anatomical characteristics compared with health controls. AI models for PACS screening are reliable and powerful, equivalent to experienced ophthalmologists.


Asunto(s)
Aprendizaje Profundo , Glaucoma de Ángulo Cerrado , Humanos , Glaucoma de Ángulo Cerrado/diagnóstico por imagen , Glaucoma de Ángulo Cerrado/diagnóstico , Estudios Transversales , Femenino , Persona de Mediana Edad , Masculino , Tomografía de Coherencia Óptica , Anciano , Segmento Anterior del Ojo/diagnóstico por imagen , Algoritmos
3.
Signal Transduct Target Ther ; 9(1): 54, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38443334

RESUMEN

Respiratory disease caused by coronavirus infection remains a global health crisis. Although several SARS-CoV-2-specific vaccines and direct-acting antivirals are available, their efficacy on emerging coronaviruses in the future, including SARS-CoV-2 variants, might be compromised. Host-targeting antivirals provide preventive and therapeutic strategies to overcome resistance and manage future outbreak of emerging coronaviruses. Cathepsin L (CTSL) and calpain-1 (CAPN1) are host cysteine proteases which play crucial roles in coronaviral entrance into cells and infection-related immune response. Here, two peptidomimetic α-ketoamide compounds, 14a and 14b, were identified as potent dual target inhibitors against CTSL and CAPN1. The X-ray crystal structures of human CTSL and CAPN1 in complex with 14a and 14b revealed the covalent binding of α-ketoamide groups of 14a and 14b to C25 of CTSL and C115 of CAPN1. Both showed potent and broad-spectrum anticoronaviral activities in vitro, and it is worth noting that they exhibited low nanomolar potency against SARS-CoV-2 and its variants of concern (VOCs) with EC50 values ranging from 0.80 to 161.7 nM in various cells. Preliminary mechanistic exploration indicated that they exhibited anticoronaviral activity through blocking viral entrance. Moreover, 14a and 14b exhibited good oral pharmacokinetic properties in mice, rats and dogs, and favorable safety in mice. In addition, both 14a and 14b treatments demonstrated potent antiviral potency against SARS-CoV-2 XBB 1.16 variant infection in a K18-hACE2 transgenic mouse model. And 14b also showed effective antiviral activity against HCoV-OC43 infection in a mouse model with a final survival rate of 60%. Further evaluation showed that 14a and 14b exhibited excellent anti-inflammatory effects in Raw 264.7 mouse macrophages and in mice with acute pneumonia. Taken together, these results suggested that 14a and 14b are promising drug candidates, providing novel insight into developing pan-coronavirus inhibitors with antiviral and anti-inflammatory properties.


Asunto(s)
COVID-19 , Hepatitis C Crónica , Humanos , Animales , Ratones , Ratas , Perros , Calpaína , Catepsina L , Antivirales/farmacología , Vacunas contra la COVID-19 , Modelos Animales de Enfermedad , Ratones Transgénicos , Antiinflamatorios
4.
Sensors (Basel) ; 24(2)2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38257656

RESUMEN

This study investigates damage characteristics, dynamic structural performance changes, and quantitative damage assessment of high-pile wharf framed bents exposed to horizontal impact loads. Through extensive testing of wharf framed bents under such loads, a damage identification approach based on stiffness, natural vibration period, and acceleration data derived from experiments is presented. The findings reveal that under horizontal impact loads, framed bents initially exhibit tensile damage and leaning piles, followed by short straight piles. Additionally, structural damage results in a reduced self-oscillation frequency and an increased amplitude decay rate. Both stiffness-based and cycle-based damage indicators effectively track the cumulative damage progression of the structure. However, the cycle-based damage indicators demonstrate superior stability and accuracy, while acceleration-based indicators precisely identify the moment of damage mutation. This research contributes to enhancing local components, implementing damage identification methods, and advancing health monitoring practices in high-pile wharf projects, aligning with the standards of scientific publications in the field.

5.
ACS Omega ; 8(17): 15341-15349, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37151524

RESUMEN

Digoxin is a cardiac glycosylated steroid-like drug with a positive inotropic effect and has been widely used in treating congestive heart failure, atrial fibrillation, atrial flutter, and other heart diseases. Digoxin is also a dangerous drug, which can cause drug poisoning at a low blood drug concentration (2.73-3.9 nmol/L, i.e., 2.14-3.05 ng/mL). Therefore, the timely detection of a patient's blood drug concentration plays a significant role in controlling blood drug concentration, reducing the occurrence of drug poisoning events, and maximizing the role of drug therapy. In this study, a DNA vector for the expression of the antidigoxin antibody Fab fragment was constructed. With the vector, Fab was expressed in E. coli and purified, and 1.2 mg of antibodies was obtained from 100 mL of culture. An immunofluorescent sensor based on the mechanism of photoinduced electron transfer was constructed by labeling additional cysteines in the heavy chain variable region and light chain variable region of the antibody Fab fragment with fluorescent dyes. The assay for digoxin with the immunosensor could be finished within 5 min with a limit of detection of 0.023 ng/mL, a detectable range of 0.023 ng/mL to 100 µg/mL, and an EC50 of 0.256 ng/mL. A new approach for the rapid detection of digoxin was developed and will contribulte to therapeutic drug monitoring.

6.
Mar Pollut Bull ; 189: 114790, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36905865

RESUMEN

The fate and transformation of PHCZs in the coastal river environment are not yet comprehensively understood. Paired river water and surface sediment were collected, and 12 PHCZs were analyzed to find out their potential sources and investigate the distribution of PHCZs between river water and sediment. The concentration of ∑PHCZs varied from 8.66 to 42.97 ng/g (mean 22.46 ng/g) in sediment and 17.91 to 81.82 ng/L (mean 39.07 ng/L) in river water. 18-B-36-CCZ was the dominant PHCZ congener in sediment, while 36-CCZ was in water. Meanwhile, the logKoc values for CZ and PHCZs were among the first calculated in the estuary and the mean logKoc varied from 4.12 for 1-B-36-CCZ to 5.63 for 3-CCZ. The logKoc values of CCZs were higher than those of BCZs, this may suggest that sediments have a higher capacity for accumulation and storage of CCZs than highly mobile environmental media.


Asunto(s)
Contaminantes Químicos del Agua , Agua , Ríos , Carbazoles/análisis , Contaminantes Químicos del Agua/análisis , China , Monitoreo del Ambiente , Sedimentos Geológicos
7.
Anal Biochem ; 665: 115069, 2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36716945

RESUMEN

Recombinant protein expression and purification are crucial in modern life sciences research. A fluorescent immunosensor termed Quenchbody (Q-body) was developed for real-time monitoring of FLAG-fused protein expression. Detection results showed that the limit of detection of the 3 × FLAG peptide detected by the TAMRA-labeled anti-FLAG Q-body was as low as 3.1 nM, with a half-maximal effective concentration of 21.4 nM. Furthermore, the anti-FLAG Q-body was used for detecting different proteins fused with a FLAG-tag at the N- or C-terminal. Subsequently, the constructed Q-body was used to monitor the real-time fermentation process of single-strand DNA-binding protein in Escherichia coli. Unlike previously reported Q-bodies that widely used Fab or scFv, the present study used a full-length anti-FLAG IgG for the first time. Owing to its excellent detection speed and sensitivity, the FLAG Q-body immunosensor has the potential to quantify and monitor target recombinant proteins in multiple biological processes in real-time.


Asunto(s)
Técnicas Biosensibles , Técnicas Biosensibles/métodos , Inmunoensayo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes de Fusión
8.
Eur J Med Chem ; 249: 115129, 2023 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-36702052

RESUMEN

The 3C-like protease (3CLpro) is essential for the replication and transcription of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), making it a promising target for the treatment of corona virus disease 2019 (COVID-19). In this study, a series of 2,3,5-substituted [1,2,4]-thiadiazole analogs were discovered to be able to inhibit 3CLpro as non-peptidomimetic covalent binders at submicromolar levels, with IC50 values ranging from 0.118 to 0.582 µM. Interestingly, these compounds were also shown to inhibit PLpro with the same level of IC50 values, but had negligible effect on proteases such as chymotrypsin, cathepsin B, and cathepsin L. Subsequently, the antiviral abilities of these compounds were evaluated in cell-based assays, and compound 6g showed potent antiviral activity with an EC50 value of 7.249 µM. It was proposed that these compounds covalently bind to the catalytic cysteine 145 via a ring-opening metathesis reaction mechanism. To understand this covalent-binding reaction, we chose compound 6a, one of the identified hit compounds, as a representative to investigate the reaction mechanism in detail by combing several computational predictions and experimental validation. The process of ring-opening metathesis was theoretically studied using quantum chemistry calculations according to the transition state theory. Our study revealed that the 2,3,5-substituted [1,2,4]-thiadiazole group could covalently modify the catalytic cysteine in the binding pocket of 3CLpro as a potential warhead. Moreover, 6a was a known GPCR modulator, and our study is also a successful computational method-based drug-repurposing study.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , Péptido Hidrolasas , Cisteína , Inhibidores de Proteasas/farmacología , Inhibidores de Proteasas/química , Cisteína Endopeptidasas/metabolismo , Antivirales/química
9.
Chem Commun (Camb) ; 59(7): 868-871, 2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36546610

RESUMEN

Macrocycles often exhibit good biological properties and potential druggability, which lead to versatile applications in the pharmaceutical industry. Herein, we report a highly efficient and practical methodology for the functionalization and macrocyclization of Trp and Trp-containing peptides via Pd(II)-catalyzed C-H alkenylation at the Trp C4 position. This method provides direct access to C4 maleimide-decorated Trp-containing peptidomimetics and maleimide-braced 17- to 30-membered peptide macrocycles. In particular, these unique macrocycles revealed low micro- to sub-micromolar EC50 values with promising anti-SARS-CoV-2 activities. Further explorations with computational methodologies and experimental validations indicated that these macrocycles exert antiviral effects through binding with the N protein of SARS-CoV-2.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Péptidos/farmacología , Péptidos/química , Ciclización , Maleimidas
10.
Plants (Basel) ; 11(19)2022 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-36235467

RESUMEN

Stems are more important to forage quality than leaves in alfalfa. To understand lignin formation at different stages in alfalfa, lignin distribution, anatomical characteristics and transcriptome profile were employed using two alfalfa cultivars. The results showed that the in vitro true digestibility (IVTD) of stems in WL168 was significantly higher than that of Zhungeer, along with the significantly lower neutral detergent fiber (NDF), acid detergent fiber (ADF) and lignin contents. In addition, Zhungeer exhibited increased staining of the xylem areas in the stems of different developmental stages compared to WL168. Interestingly, the stems of WL168 appeared intracellular space from the stage 3, while Zhungeer did not. The comparative transcriptome analysis showed that a total of 1993 genes were differentially expressed in the stem between the cultivars, with a higher number of expressed genes in the stage 4. Of the differentially expressed genes, starch and sucrose metabolism as well as phenylpropanoid biosynthesis pathways were the most significantly enriched pathways. Furthermore, expression of genes involved in lignin biosynthesis such as PAL, 4CL, HCT, CAD, COMT and POD coincides with the anatomic characteristics and lignin accumulation. These results may help elucidate the regulatory mechanisms of lignin biosynthesis and improve forage quality in alfalfa.

11.
Bioorg Chem ; 127: 105989, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35777236

RESUMEN

Given the significant clinical potential of human plasminogen Kringle 5 on tumours, it is crucial to seek its receptors for a thorough comprehension of its physiological functions and mechanism. Eleven candidates have been screened out in our previous works. In the present work, we further inquired whether the candidate, von Willebrand factor type A domain 1 in coagulation factor C homology protein (abbr. vWA1), was a potential receptor of Kringle 5, and investigated their binding mechanism by bio-specific experiments, frontal affinity analysis (FA), and molecular dynamic simulation (MDS). After the potential was validated by bio-specific experiments, the FA results stated that vWA1 exhibited a strong interaction towards Kringle 5 in the proportion of 1:1 with the binding constant of 4.18 × 104 L/mol. The MDS results showed that the binding was mainly driven by electrostatic and Van der Waals forces and occurred spontaneously, during which vWA1 and Kringle 5 mutually fit each other by conformational changing into more flexible and suitable structures including fluctuations for five loops and partial transformation into a random coil for α6-helix in vWA1. Moreover, lysine binding site Leu71-Tyr74 was speculated responsible for Kringle 5 in binding and Tyr72 to be the key amino acid residue. In short, this work not only confirmed vWA1 as a potential Kringle 5 receptor but also provided valuable information on the detailed binding, facilitating the application development of Kringle 5 in regulating immune or inhibiting tumour migration through vWA1.


Asunto(s)
Proteínas de la Matriz Extracelular , Simulación de Dinámica Molecular , Secuencia de Aminoácidos , Sitios de Unión , Humanos , Ligandos , Espectroscopía de Resonancia Magnética , Fragmentos de Péptidos , Plasminógeno , Unión Proteica , Conformación Proteica
13.
Sci Rep ; 12(1): 2289, 2022 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-35145182

RESUMEN

The occurrence of gene duplication/amplification (GDA) provide potential material for adaptive evolution with environmental stress. Several molecular models have been proposed to explain GDA, recombination via short stretches of sequence similarity plays a crucial role. By screening genomes for such events, we propose a "SRS (short repeated sequence) *N + unit + SRS*N" amplified unit under USCE (unequal sister-chromatid exchange) for tandem amplification mediated by SRS with different repeat numbers in eukaryotes. The amplified units identified from 2131 well-organized amplification events that generate multi gene/element copy amplified with subsequent adaptive evolution in the respective species. Genomic data we analyzed showed dynamic changes among related species or subspecies or plants from different ecotypes/strains. This study clarifies the characteristics of variable copy number SRS on both sides of amplified unit under USCE mechanism, to explain well-organized gene tandem amplification under environmental stress mediated by SRS in all eukaryotes.


Asunto(s)
Eucariontes/genética , Amplificación de Genes , Modelos Moleculares , Secuencias Repetitivas de Ácidos Nucleicos , Adaptación Biológica/genética , Evolución Biológica , Ambiente
14.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 51(4): 430-437, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37202106

RESUMEN

OBJECTIVE: To screen activators of 2,3-diphosphoglycerate (BPG) mutase (BPGM) from Chinese herb medicines, so as to improve the hypoxia tolerance of erythrocytes. METHODS: BPGM was used as the receptor and Chinese medicine ingredients database was used as the ligand in the study. After Lipinski rule of five screening, LibDock and CDOCKER docking were used for virtual screening. The effect of the screened compounds on the affinity of BPGM in erythrocytes was verified. Finally, the erythrocytes were incubated in vitro to establish the erythrocyte hypoxia model, and the effect of the compound on the activity of BPGM in the erythrocyte hypoxia model was verified. RESULTS: Ten compounds with highest binding affinity to BPGM were selected by LibDock and CDOCKER, and the cytoplasm protein was incubated with the ten compounds. Compared with blank control group, methyl rosmarinate group, dihydrocurcumin high dose group, octahydrocurcumin medium dose group and coniferyl ferulate high dose group were able to further activate the BPGM, significantly increase the levels of 2, 3-BPG in normal erythrocytes (all P<0.05); while the low dose of tetrahydrocurcumin, high dose and low dose of aurantiamide, hexahydrocurcumin and medium dose of N- (p-coumaroyl) serotonin had a tendency to increase the contents of 2,3-BPG in normal erythrocytes (all P>0.05). In the hypoxic red blood cells, the medium dose methyl rosmarinate, medium dose octahydrocurcumin, high dose hexahydrocurcumin and medium dose N-(p-coumaroyl) serotonin could significantly increase the contents of 2,3-BPG (all P<0.05). CONCLUSION: The methyl rosmarinate, octahydrocurcumin, hexahydrocurcumin and N-(p-coumaroyl) serotonin could activate BPGM and increase the contents of 2,3-BPG in hypoxic erythrocytes.


Asunto(s)
Bisfosfoglicerato Mutasa , Medicina Tradicional China , Humanos , Bisfosfoglicerato Mutasa/metabolismo , Serotonina , Hipoxia
16.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 50(5): 568-574, 2021 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-34986540

RESUMEN

To investigate the active compounds from on the heart and brain of mice at simulated high altitude.Fifty healthy male adult BALB/c mice were randomly divided into normal control group, hypoxic model group, acetazolamide group, petroleum ether extract of (PESI) group and octacosan group with 10 mice in each group. Acetazolamide group, PESI group and octacosan group were treated with acetazolamide PESI (200 mg/kg) or octacosan by single tail vein injection, respectively. Except normal control group, the mice were exposed to a simulated high altitude of for in an animal decompression chamber. After the mice were sacrificed by cervical dislocation, the heart and brain were histologically observed by HE staining; superoxide dismutase (SOD) activity, total anti-oxidant capacity (T-AOC) and the content of malondialdehyde (MDA) in plasma, heart and brain tissues were detected by WST-1 method, ABTS method and TBA method, respectively; lactic acid and lactate dehydrogenase (LDH) activity in plasma, heart and brain tissues were detected by colorimetric method and microwell plate method, respectively; ATP content and ATPase activity in heart and brain tissues were detected by colorimetric method. PESI and octacosane significantly attenuated the pathological damages of heart and brain tissue at simulated high altitude; increased SOD activity, T-AOC and LDH activity, and decreased the contents of MDA and lactic acid in plasma, heart and brain tissues; increased the content of ATP in heart and brain tissues; increased the activities of Na-K ATPase, Mg ATPase, Ca ATPase and Ca-Mg ATPase in myocardial tissue; and increased the activities of Mg ATPase, Ca-Mg ATPase in brain tissue. PESI and octacosan exert anti-hypoxic activity by improving the antioxidant capacity, reducing the free radical levels, promoting the anaerobic fermentation, and alleviating the energy deficiency and metabolic disorders caused by hypoxia in mice.


Asunto(s)
Altitud , Superóxido Dismutasa , Animales , Encéfalo/metabolismo , Corazón , Masculino , Malondialdehído , Ratones , Ratones Endogámicos BALB C , Superóxido Dismutasa/metabolismo
17.
ACS Infect Dis ; 7(6): 1409-1422, 2021 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-33183004

RESUMEN

Arenaviruses are a large family of enveloped negative-strand RNA viruses that include several causative agents of severe hemorrhagic fevers. Currently, there are no FDA-licensed drugs to treat arenavirus infection except for the off-labeled use of ribavirin. Here, we performed antiviral drug screening against the Old World arenavirus lymphocytic choriomeningitis virus (LCMV) using an FDA-approved drug library. Five drug candidates were identified, including mycophenolic acid, benidipine hydrochloride, clofazimine, dabrafenib, and apatinib, for having strong anti-LCMV effects. Further analysis indicated that benidipine hydrochloride inhibited LCMV membrane fusion, and an adaptive mutation on the LCMV glycoprotein D414 site was found to antagonize the anti-LCMV activity of benidipine hydrochloride. Mycophenolic acid inhibited LCMV replication by depleting GTP production. We also found mycophenolic acid, clofazimine, dabrafenib, and apatinib can inhibit the newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Owing to their FDA-approved status, these drug candidates can potentially be used rapidly in the clinical treatment of arenavirus and SARS-CoV-2 infection.


Asunto(s)
COVID-19 , Preparaciones Farmacéuticas , Ensayos Analíticos de Alto Rendimiento , Humanos , SARS-CoV-2 , Replicación Viral
18.
J Chromatogr A ; 1620: 460986, 2020 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-32173023

RESUMEN

Human plasminogen Kringle 5 is known to pose a more potent anti-angiogenesis effect by inducing endothelial cell apoptosis. Our previous studies have identified the peptide IGNSNTL as a binding sequence of Kringle 5 using Ph.D.-7 phage display peptide library and enzyme-linked immunosorbent assay. Here, eleven proteins were screened and summarized by BLAST, laminin α3 chain G1 domain (LG1) was considered as the most potential receptor based on E value and domain function. The specific interaction of them was directly revealed through ligand blot and a strong concentration-dependent manner occurred between them (Ka 4.30 × 105 L mol-1) in frontal chromatography observation. Moreover, R10A/P83R substitution Kringle 5 decreased the affinity capacity to LG1. Furthermore, a remarkable conformational change from random coil3 to α helix and α1 helix to random coil were observed to the structural compactness and stability for LG1. Surface loops and coils also showed fluctuations up to some extent, giving the binding surface greater flexibility and correspondingly allowing for induced-fit binding, which was -23.87 kcal mol-1 of the free energy with electrostatic force as a main driver. Taken together, not only effective theoretical prediction and experiment validated that LG1 is receptor of Kringle 5, but also give an new perspective of the binding mechanism of Kringle 5 and its specific receptor and could facilitate the development of novel agent targeted toward pathologic angiogenesis.


Asunto(s)
Células Endoteliales/metabolismo , Laminina/química , Simulación de Dinámica Molecular , Fragmentos de Péptidos/metabolismo , Plasminógeno/metabolismo , Secuencia de Aminoácidos , Sitios de Unión , Humanos , Cinética , Ligandos , Proteínas Mutantes/química , Biblioteca de Péptidos , Unión Proteica , Dominios Proteicos , Termodinámica
19.
J Pharmacol Exp Ther ; 364(1): 55-69, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29025979

RESUMEN

Modern lifestyle factors (high-caloric food rich in fat) and daily chronic stress are important risk factors for metabolic disturbances. Increased hypothalamic-pituitary-adrenal (HPA) axis activity and the subsequent excess production of glucocorticoids (GCs) in response to chronic stress (CS) leads to increases in metabolic complications, such as type 2 diabetes and insulin resistance (IR). Melatonin (MLT), which protects several regulatory components of the HPA axis from GC-induced deterioration, might improve glucose homeostasis. Piromelatine is a melatonin receptor-1/melatonin receptor-2 (MT1/MT2) agonist with high affinity for MLT receptors and a longer duration of action than MLT. The objective of the present study was to explore the potential effects of piromelatine on glucose and lipid metabolism and insulin sensitivity in rats with IR induced by a high-fat diet combined with CS (CF). The results showed that piromelatine prevented the suppression of body weight gain and energy intake induced by CF and normalized CF-induced hyperglycemia and homeostasis model assessment-IR index, which suggests that piromelatine prevented whole-body IR. Piromelatine also prevented CF-induced dysregulation of genes involved in glucose and lipid metabolism, including proinflammatory cytokines, in adipose tissue. In addition, piromelatine also attenuated CF-induced excess free corticosterone release, increased glucocorticoid receptor expression, and decreased 11ß-hydroxysteroid dehydrogenase-1 expression, suggesting that piromelatine might ameliorate impaired glucose metabolism and prevent IR by normalizing HPA-axis functions. In conclusion, piromelatine might be a novel therapeutic agent for glucose intolerance and IR.


Asunto(s)
Glucemia/efectos de los fármacos , Dieta Alta en Grasa/efectos adversos , Glucosa/antagonistas & inhibidores , Indoles/uso terapéutico , Piranos/uso terapéutico , Receptores de Melatonina/agonistas , Estrés Psicológico/tratamiento farmacológico , Animales , Glucemia/metabolismo , Enfermedad Crónica , Glucosa/metabolismo , Indoles/farmacología , Masculino , Piranos/farmacología , Ratas , Ratas Wistar , Receptores de Melatonina/metabolismo , Estrés Psicológico/metabolismo
20.
Eur J Pharmacol ; 812: 225-233, 2017 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-28687198

RESUMEN

Excessive glucocorticoid (GC) in type 2 diabetes mellitus (T2DM) reduces insulin sensitivity, impairs ß-cell function, increases gluconeogenesis and glycogenolysis, impairs glucose uptake and metabolism, and reduces the insulinotropic effects of glucagon-like peptide 1. Melatonin, which serves as a physiological regulator of the hypothalamic-pituitary-adrenal (HPA) axis, has been suggested to have anti-diabetic effects. The objective of the present study was to investigate the effect of the MT1/MT2 melatonin agonist Neu-P11 on glucose and lipid metabolism in T2DM rats induced by a high fat diet combined with low doses of streptozotocin. T2DM rats were intragastrically administered melatonin (20mg/kg), Neu-P11 (20, 10, 5mg/kg), or a vehicle for 4 weeks. The results showed that the increased food intake, water consumption, hyperglycemia, glucose intolerance, and insulin resistance in T2DM rats were all improved by Neu-P11 treatment. Neu-P11 increased GC receptor expression and suppressed 11ß-hydroxysteroid dehydrogenase 1 activity in the hippocampus by enhancing GC sensitivity and HPA feedback, thus decreasing the high GC levels. Transcript levels of the glucose metabolism-related genes peroxisome proliferator-activated receptor-γ, glucose transporter type-4, and adiponectin in adipose tissue were significantly increased after Neu-P11 treatment, while leptin mRNA was significantly decreased. Furthermore, MT1 and MT2 protein levels were enhanced by Neu-P11. These data suggest that normalization of the hyperactivated HPA axis by melatonin and Neu-P11 in T2DM regulates metabolic profiles and insulin sensitivity, which may attenuate insulin resistance and glucose homeostasis. Because Neu-P11 has superior pharmacokinetics and a longer half-life than melatonin, it might be beneficial in treating obesity and T2DM.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipotálamo/efectos de los fármacos , Indoles/farmacología , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Piranos/farmacología , Receptor de Melatonina MT1/agonistas , Receptor de Melatonina MT2/agonistas , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/genética , Adiponectina/genética , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/metabolismo , Animales , Glucemia/metabolismo , Peso Corporal/efectos de los fármacos , Corticosterona/sangre , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatología , Ingestión de Líquidos/efectos de los fármacos , Ayuno/sangre , Femenino , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Transportador de Glucosa de Tipo 4/genética , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Indoles/uso terapéutico , Resistencia a la Insulina , Leptina/genética , PPAR gamma/genética , Piranos/uso terapéutico , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Wistar
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