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1.
Cell Discov ; 10(1): 91, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39223120

RESUMEN

Prolactin-releasing peptide (PrRP) is an RF-amide neuropeptide that binds and activates its cognate G protein-coupled receptor, prolactin-releasing peptide receptor (PrRPR), also known as GPR10. PrRP and PrRPR are highly conserved across mammals and involved in regulating a range of physiological processes, including stress response, appetite regulation, pain modulation, cardiovascular function, and potentially reproductive functions. Here we present cryo-electron microscopy structures of PrRP-bound PrRPR coupled to Gq or Gi heterotrimer, unveiling distinct molecular determinants underlying the specific recognition of the ligand's C-terminal RF-amide motif. We identify a conserved polar pocket that accommodates the C-terminal amide shared by RF-amide peptides. Structural comparison with neuropeptide Y receptors reveals both similarities and differences in engaging the essential RF/RY-amide motifs. Our findings demonstrate the general mechanism governing RF-amide motif recognition by PrRPR and RF-amide peptide receptors, and provide a foundation for elucidating activation mechanisms and developing selective drugs targeting this important peptide-receptor system.

2.
BMC Infect Dis ; 24(1): 904, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39223461

RESUMEN

BACKGROUND: To mitigate hospital-acquired transmission of coronavirus disease 2019 (COVID-19), various prevention and control measures have been strictly implemented in medical institutions. These stringent measures can potentially reduce the incidence of hospital-acquired respiratory infections. This study aimed to assess if there were changes in the prevalence of hospital-acquired respiratory infections during a period of national attention focused on COVID-19 prevention. METHODS: A retrospective analysis of the clinical data from adult patients with hospital-acquired respiratory infections admitted between October and December 2019 and during the same period in 2020 was performed. All patients were referred from a general hospital in Beijing China and COVID-19 patients were not treated at the hospital. Hospital-acquired respiratory infections were diagnosed based on the criteria of the Centers for Disease Control and Prevention/National Healthcare Safety Network (CDC/NHSN). A comparison of the incidence and mortality rate of hospital-acquired respiratory infections between the two selected time periods was conducted. Additionally, multivariate logistics regression analysis was used to identify mortality-associated risk factors. RESULTS: This study included 2,211 patients from October to December 2019 (pre-COVID-19 pandemic) and 2,921 patients from October to December 2020 (during the COVID-19 pandemic). The incidence of hospital-acquired respiratory infections in 2019 and 2020 was 4.7% and 2.9%, respectively, with odds ratio (OR): 0.61, 95% confidence interval (CI): 0.46-0.81, and P = 0.001. In-hospital mortality of hospital-acquired respiratory infections in 2019 and 2020 was 30.5% and 38.4%, respectively, with OR: 1.42, 95%CI: 0.78-2.59, and P = 0.25. Multivariate logistics regression analysis revealed that a history of previous malignancy (OR: 2.50, 95%CI: 1.16-5.35, P = 0.02), was associated with in-hospital mortality. CONCLUSIONS: The incidence of hospital-acquired respiratory infections was significantly decreased following the implementation of various prevention and control measures during the COVID-19 pandemic. A history of previous malignancy was associated with higher in-hospital mortality in older inpatients with hospital-acquired respiratory infections.


Asunto(s)
COVID-19 , Infección Hospitalaria , Hospitales Generales , Infecciones del Sistema Respiratorio , Humanos , COVID-19/epidemiología , COVID-19/mortalidad , Estudios Retrospectivos , Masculino , Femenino , Anciano , Hospitales Generales/estadística & datos numéricos , Persona de Mediana Edad , China/epidemiología , Incidencia , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/virología , Infecciones del Sistema Respiratorio/mortalidad , Infección Hospitalaria/epidemiología , Anciano de 80 o más Años , SARS-CoV-2 , Adulto , Factores de Riesgo , Pacientes Internos/estadística & datos numéricos , Mortalidad Hospitalaria
3.
Diabetes Metab Syndr Obes ; 17: 2955-2966, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39135891

RESUMEN

Background: Physical activity (PA) exerts an important influence on glycemic control in type 2 diabetes (T2D) patients. Alterations in body composition in patients with T2D may be involved in the overall pathophysiologic process, but PAs and alterations in body composition have been poorly studied. Methods: A total of 615 patients with T2D were selected by convenient sampling. The patients were investigated with the International Physical Activity Questionnaire (IPAQ-S). Moreover, biochemical indices were collected, and the progression of the body composition of the subjects was determined via dual-energy X-ray absorptiometry (DXA). The variables included lumbar bone mineral density (LSBMD), femoral neck bone mineral density (FNBMD), hip bone mineral density (HBMD), whole-body bone mineral density (TBMD), limb skeletal muscle mass index (ASMI), whole-body fat percentage (B-FAT) and trunk fat percentage (T-FAT). Moreover, the levels of physical activity (high level of physical activity [H-PA], medium level of physical activity [M-PA] and low level of physical activity [L-PA]) were divided into three groups to analyze the changes in patient body composition with changes in physical activity level. Results: One-way analysis of variance showed that ß-CTX, TP1NP, HbA1c, B-FAT and T-FAT increased significantly (p<0.05), while 25(OH)D, LSBMD, FNBMD, HBMD, TBMD and ASMI decreased significantly (p<0.001) with the decrease of physical activity. However, there was no significant difference in serum lipids between lnHOMA-ir and lnHOMA-ß (p>0.05). Multiple linear regression model was established to gradually adjust for clinical confounding factors. It was found that physical activity level was independently positively correlated with LSBMD, FNBMD, HBMD, TBMD, and ASMI, and was independently negatively correlated with B-FAT and T-FAT in patients with type 2 diabetes. Conclusion: A lack of physical activity is an independent risk factor for decreased bone mineral density, decreased skeletal muscle content and increased fat content in patients with T2D.

4.
Carbohydr Polym ; 343: 122426, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39174115

RESUMEN

The intricate microenvironment of diabetic wounds characterized by hyperglycemia, intense oxidative stress, persistent bacterial infection and complex pH fluctuations hinders the healing process. Herein, an injectable multifunctional hydrogel (QPTx) was developed, which exhibited excellent mechanical performance and triple responsiveness to pH, temperature, and glucose due to dynamic covalent cross-linking involving dynamic Schiff base bonds and phenylboronate esters with phenylboronic-modified quaternized chitosan (QCS-PBA), polydopamine coated tunicate cellulose crystals (PDAn@TCNCs) and polyvinyl alcohol (PVA). Furthermore, the hydrogels can incorporate insulin (INS) drugs to adapt to the complex and variable wound environment in diabetic patients for on-demand drug release that promote diabetic wound healing. Based on various excellent properties of the colloidal materials, the hydrogels were evaluated for self-healing, rheological and mechanical properties, in vitro insulin response to pH/temperature/glucose release, antibacterial, antioxidant, tissue adhesion, coagulation, hemostasis in vivo and in vitro, and biocompatibility and biodegradability. By introducing PDAn@TCNCs particles, the hydrogel has photothermal antibacterial activity, enhanced adhesion and oxidation resistance. We further demonstrated that these hydrogel dressings significantly improved the healing process compared to commercial dressings (Tegaderm™) in full-layer skin defect models. All indicated that the glucose-responsive QPTx hydrogel platform has great potential for treating diabetic wounds.


Asunto(s)
Antibacterianos , Vendajes , Celulosa , Hidrogeles , Nanopartículas , Cicatrización de Heridas , Cicatrización de Heridas/efectos de los fármacos , Celulosa/química , Celulosa/farmacología , Celulosa/análogos & derivados , Hidrogeles/química , Hidrogeles/farmacología , Animales , Antibacterianos/farmacología , Antibacterianos/química , Nanopartículas/química , Staphylococcus aureus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Insulina/administración & dosificación , Urocordados/química , Quitosano/química , Polímeros/química , Polímeros/farmacología , Masculino , Indoles/química , Indoles/farmacología , Alcohol Polivinílico/química , Liberación de Fármacos , Humanos , Concentración de Iones de Hidrógeno , Diabetes Mellitus Experimental/tratamiento farmacológico , Ratones , Ratas , Ratas Sprague-Dawley
5.
Heliyon ; 10(12): e32901, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38994069

RESUMEN

A new method is required to address the challenge of predicting process parameters in high-temperature, high-pressure industrial processes. This study proposes a multi-model Long Short-Term Memory (LSTM) network prediction algorithm with irregular time interval sequences to predict the silicon yield in converter steelmaking. The experimental results demonstrate that this algorithm performs better than comparable neural network models in classifying high-dimensional, redundant industrial production data with noise and outliers. The algorithm is evaluated using data from a steel plant. The proposed algorithm has lower errors for predicting the alloy yield than other neural network models. An average mean absolute error (MAE) of less than 0.01 confirms the algorithm's feasibility and practicality.

6.
Meat Sci ; 216: 109581, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38970933

RESUMEN

This study aimed to assess the effect of dietary arginine supplementation on muscle structure and meat characteristics of lambs also considering lipid oxidation products and to contribute to reveal its mechanisms of action using tandem mass tagging (TMT) proteomics. Eighteen lambs were allocated to two dietary treatment groups: control diet or control diet with the addition of 1% L-arginine. The results revealed that dietary arginine supplementation increased muscle fibre diameter and cross-sectional area (P < 0.05), which was attributable to protein deposition, as evidenced by increased RNA content, RNA/DNA ratio, inhibition of apoptotic enzyme activity, and alterations in the IGF-1/Akt signaling pathway (P < 0.05). In addition, dietary arginine elevated pH24h, a* values, and IMF content, decreased shear force value and backfat thickness (P < 0.05), as well as decreased the formation of lipid oxidation products involved in meat flavor including hexanal, heptanal, octanal, nonanal and 1-octen-3-ol by increasing the antioxidant capacity of the muscle (P < 0.05). The proteomics results suggested that seven enrichment pathways may be potential mechanisms by which arginine affected the muscle structure and meat characteristics of lambs. In summary, arginine supplementation in lamb diets provides a safe and effective way to improve meat quality, and antioxidant capacity of muscle of lamb.


Asunto(s)
Alimentación Animal , Arginina , Dieta , Suplementos Dietéticos , Músculo Esquelético , Carne Roja , Oveja Doméstica , Animales , Arginina/administración & dosificación , Arginina/farmacología , Carne Roja/análisis , Dieta/veterinaria , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/química , Alimentación Animal/análisis , Masculino , Oxidación-Reducción , Antioxidantes , Metabolismo de los Lípidos/efectos de los fármacos
9.
Proc Natl Acad Sci U S A ; 121(26): e2321710121, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38885377

RESUMEN

Somatostatin receptor 5 (SSTR5) is an important G protein-coupled receptor and drug target for neuroendocrine tumors and pituitary disorders. This study presents two high-resolution cryogenicelectron microscope structures of the SSTR5-Gi complexes bound to the cyclic neuropeptide agonists, cortistatin-17 (CST17) and octreotide, with resolutions of 2.7 Å and 2.9 Å, respectively. The structures reveal that binding of these peptides causes rearrangement of a "hydrophobic lock", consisting of residues from transmembrane helices TM3 and TM6. This rearrangement triggers outward movement of TM6, enabling Gαi protein engagement and receptor activation. In addition to hydrophobic interactions, CST17 forms conserved polar contacts similar to somatostatin-14 binding to SSTR2, while further structural and functional analysis shows that extracellular loops differently recognize CST17 and octreotide. These insights elucidate agonist selectivity and activation mechanisms of SSTR5, providing valuable guidance for structure-based drug development targeting this therapeutically relevant receptor.


Asunto(s)
Octreótido , Receptores de Somatostatina , Receptores de Somatostatina/metabolismo , Receptores de Somatostatina/agonistas , Receptores de Somatostatina/química , Humanos , Octreótido/química , Octreótido/farmacología , Octreótido/metabolismo , Neuropéptidos/metabolismo , Neuropéptidos/química , Microscopía por Crioelectrón , Unión Proteica , Péptidos Cíclicos/química , Péptidos Cíclicos/farmacología , Péptidos Cíclicos/metabolismo , Somatostatina/metabolismo , Somatostatina/química , Somatostatina/análogos & derivados , Modelos Moleculares , Células HEK293
10.
Adv Healthc Mater ; : e2401038, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38923359

RESUMEN

This study fabricates a functionalized scaffold by cryogenic three-dimensional (3D) printing using an aminated poly-L-lactic acid (EPLA) solution containing nanosilver/zinc-coated black phosphorus (BP@(Zn+Ag)) nanocomposites. The nanocomposites are prepared by a green method of in situ photodeposition of silver and zinc nanoparticles (AgNPs and ZnNPs) on BP nanosheets (BPNs) under visible light irradiation without any chemical reductant. Scanning electron microscope (SEM) and X-ray energy dispersive spectrometer (EDS) confirm the uniform distribution of BP@(Zn+Ag) nanoparticles in the EPLA nanofibrous matrix. The in vitro tests show that the fabricated BP@(Zn+Ag)/EPLA nanofibrous scaffold exhibits excellent antibacterial activity (over 96%) against E. coli and S. aureus, as well as enhanced cell viability and osteogenic activity to facilitate the growth and differentiation of osteoblasts. The in vivo rat calvarial defect model also demonstrates that the BP@(Zn+Ag)/EPLA nanofibrous scaffold promotes new bone tissue formation around the implant site. Therefore, the prepared multifunctional 3D printed BP@(Zn+Ag)/EPLA nanofibrous scaffold has great potential for bone tissue engineering (BTE) applications.

11.
Water Res ; 259: 121848, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824797

RESUMEN

Chronic exposure to elevated geogenic arsenic (As) and fluoride (F-) concentrations in groundwater poses a significant global health risk. In regions around the world where regular groundwater quality assessments are limited, the presence of harmful levels of As and F- in shallow groundwater extracted from specific wells remains uncertain. This study utilized an enhanced stacking ensemble learning model to predict the distributions of As and F- in shallow groundwater based on 4,393 available datasets of observed concentrations and forty relevant environmental factors. The enhanced model was obtained by fusing well-suited Extreme Gradient Boosting, Random Forest, and Support Vector Machine as the base learners and a structurally simple Linear Discriminant Analysis as the meta-learner. The model precisely captured the patchy distributions of groundwater As and F- with an AUC value of 0.836 and 0.853, respectively. The findings revealed that 9.0% of the study area was characterized by a high As risk in shallow groundwater, while 21.2% was at high F- risk identified as having a high risk of fluoride contamination. About 0.2% of the study area shows elevated levels of both of them. The affected populations are estimated at approximately 7.61 million, 34.1 million, and 0.2 million, respectively. Furthermore, sedimentary environment exerted the greatest influence on distribution of groundwater As, with human activities and climate following closely behind at 29.5%, 28.1%, and 21.9%, respectively. Likewise, sedimentary environment was the primary factor affecting groundwater F- distribution, followed by hydrogeology and soil physicochemical properties, contributing 27.8%, 24.0%, and 23.3%, respectively. This study contributed to the identification of health risks associated with shallow groundwater As and F-, and provided insights into evaluating health risks in regions with limited samples.


Asunto(s)
Arsénico , Monitoreo del Ambiente , Fluoruros , Agua Subterránea , Contaminantes Químicos del Agua , Agua Subterránea/química , Fluoruros/análisis , Arsénico/análisis , Contaminantes Químicos del Agua/análisis , China
12.
Curr Biol ; 34(12): 2702-2711.e6, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38776901

RESUMEN

Studying the independent evolution of similar traits provides valuable insights into the ecological and genetic factors driving phenotypic evolution.1 The transition from outcrossing to self-fertilization is common in plant evolution2 and is often associated with a reduction in floral attractive features such as display size, chemical signals, and pollinator rewards.3 These changes are believed to result from the reallocation of the resources used for building attractive flowers, as the need to attract pollinators decreases.2,3 We investigated the similarities in the evolution of flower fragrance following independent transitions to self-fertilization in Capsella.4,5,6,7,8,9 We identified several compounds that exhibited similar changes in different selfer lineages, such that the flower scent composition reflects mating systems rather than evolutionary history within this genus. We further demonstrate that the repeated loss of ß-ocimene emission, one of the compounds most strongly affected by these transitions, was caused by mutations in different genes. In one of the Capsella selfing lineages, the loss of its emission was associated with a mutation altering subcellular localization of the ortholog of TERPENE SYNTHASE 2. This mutation appears to have been fixed early after the transition to selfing through the capture of variants segregating in the ancestral outcrossing population. The large extent of convergence in the independent evolution of flower scent, together with the evolutionary history and molecular consequences of a causal mutation, suggests that the emission of specific volatiles evolved as a response to changes in ecological pressures rather than resource limitation.


Asunto(s)
Evolución Molecular , Flores , Odorantes , Autofecundación , Flores/genética , Autofecundación/genética , Odorantes/análisis , Polinización , Alquenos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Monoterpenos Acíclicos
13.
Microorganisms ; 12(5)2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38792808

RESUMEN

Enzyme-production microorganisms typically occupy a dominant position in composting, where cellulolytic microorganisms actively engage in the breakdown of lignocellulose. Exploring strains with high yields of cellulose-degrading enzymes holds substantial significance for the industrial production of related enzymes and the advancement of clean bioenergy. This study was inclined to screen cellulolytic bacteria, conduct genome analysis, mine cellulase-related genes, and optimize cellulase production. The potential carboxymethylcellulose-hydrolyzing bacterial strain Z2.6 was isolated from the maturation phase of pig manure-based compost with algae residuals as the feedstock and identified as Bacillus velezensis. In the draft genome of strain Z2.6, 31 related cellulolytic genes were annotated by the CAZy database, and further validation by cloning documented the existence of an endo-1,4-ß-D-glucanase (EC 3.2.1.4) belonging to the GH5 family and a ß-glucosidase (EC 3.2.1.21) belonging to the GH1 family, which are predominant types of cellulases. Through the exploration of ten factors in fermentation medium with Plackett-Burman and Box-Behnken design methodologies, maximum cellulase activity was predicted to reach 2.98 U/mL theoretically. The optimal conditions achieving this response were determined as 1.09% CMC-Na, 2.30% salinity, and 1.23% tryptone. Validation under these specified conditions yielded a cellulose activity of 3.02 U/mL, demonstrating a 3.43-fold degree of optimization. In conclusion, this comprehensive study underscored the significant capabilities of strain Z2.6 in lignocellulolytic saccharification and its potentialities for future in-depth exploration in biomass conversion.

14.
Cell Death Dis ; 15(5): 316, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38710691

RESUMEN

S100 calcium-binding protein 16 (S100A16) is implicated in both chronic kidney disease (CKD) and acute kidney injury (AKI). Previous research has shown that S100A16 contributes to AKI by facilitating the ubiquitylation and degradation of glycogen synthase kinase 3ß (GSK3ß) and casein kinase 1α (CK1α) through the activation of HMG-CoA reductase degradation protein 1 (HRD1). However, the mechanisms governing S100A16-induced HRD1 activation and the upregulation of S100A16 expression in renal injury are not fully understood. In this study, we observed elevated expression of Hypoxia-inducible Factor 1-alpha (HIF-1α) in the kidneys of mice subjected to ischemia-reperfusion injury (IRI). S100A16 deletion attenuated the increased HIF-1α expression induced by IRI. Using a S100A16 knockout rat renal tubular epithelial cell line (NRK-52E cells), we found that S100A16 knockout effectively mitigated apoptosis during hypoxic reoxygenation (H/R) and cell injury induced by TGF-ß1. Our results revealed that H/R injuries increased both protein and mRNA levels of HIF-1α and HRD1 in renal tubular cells. S100A16 knockout reversed the expressions of HIF-1α and HRD1 under H/R conditions. Conversely, S100A16 overexpression in NRK-52E cells elevated HIF-1α and HRD1 levels. HIF-1α overexpression increased HRD1 and ß-catenin while decreasing GSK-3ß. HIF-1α inhibition restored HRD1 and ß-catenin upregulation and GSK-3ß downregulation by cellular H/R injury. Notably, Chromatin immunoprecipitation (ChIP) and luciferase reporter assays demonstrated HIF-1α binding signals on the HRD1 promoter, and luciferase reporter gene assays confirmed HIF-1α's transcriptional regulation of HRD1. Additionally, we identified Transcription Factor AP-2 Beta (TFAP2B) as the upregulator of S100A16. ChIP and luciferase reporter assays confirmed TFAP2B as a transcription factor for S100A16. In summary, this study identifies TFAP2B as the transcription factor for S100A16 and demonstrates HIF-1α regulation of HRD1 transcription within the S100A16-HRD1-GSK3ß/CK1α pathway during renal hypoxia injury. These findings provide crucial insights into the molecular mechanisms of kidney injury, offering potential avenues for therapeutic intervention.


Asunto(s)
Glucógeno Sintasa Quinasa 3 beta , Subunidad alfa del Factor 1 Inducible por Hipoxia , Animales , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Ratones , Ratas , Proteínas S100/metabolismo , Proteínas S100/genética , Daño por Reperfusión/metabolismo , Daño por Reperfusión/genética , Daño por Reperfusión/patología , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Transducción de Señal , Masculino , Lesión Renal Aguda/metabolismo , Lesión Renal Aguda/patología , Lesión Renal Aguda/genética , Ratones Endogámicos C57BL , Riñón/metabolismo , Riñón/patología , Apoptosis , Línea Celular , Hipoxia de la Célula , Ratones Noqueados
15.
Curr Genomics ; 25(2): 88-104, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38751598

RESUMEN

Objectives: This study aims to assess the prognostic implications of gene signature of the tertiary lymphoid structures (TLSs) in head and neck squamous cell carcinoma (HNSCC) and scrutinize the influence of TLS on immune infiltration. Methods: Patients with HNSCC from the Cancer Genome Atlas were categorized into high/low TLS signature groups based on the predetermined TLS signature threshold. The association of the TLS signature with the immune microenvironment, driver gene mutation status, and tumor mutational load was systematically analyzed. Validation was conducted using independent datasets (GSE41613 and GSE102349). Results: Patients with a high TLS signature score exhibited better prognosis compared to those with a low TLS signature score. The group with a high TLS signature score had significantly higher immune cell subpopulations compared to the group with a low TLS signature score. Moreover, the major immune cell subpopulations and immune circulation characteristics in the tumor immune microenvironment were positively correlated with the TLS signature. Mutational differences in driver genes were observed between the TLS signature high/low groups, primarily in the cell cycle and NRF2 signaling pathways. Patients with TP53 mutations and high TLS signature scores demonstrated a better prognosis compared to those with TP53 wild-type. In the independent cohort, the relationship between TLS signatures and patient prognosis and immune infiltration was also confirmed. Additionally, immune-related biological processes and signaling pathways were activated with elevated TLS signature. Conclusion: High TLS signature is a promising independent prognostic factor for HNSCC patients. Immunological analysis indicated a correlation between TLS and immune cell infiltration in HNSCC. These findings provide a theoretical basis for future applications of TLS signature in HNSCC prognosis and immunotherapy.

16.
Cell Discov ; 10(1): 48, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38710677

RESUMEN

Melanin-concentrating hormone (MCH) is a cyclic neuropeptide that regulates food intake, energy balance, and other physiological functions by stimulating MCHR1 and MCHR2 receptors, both of which are class A G protein-coupled receptors. MCHR1 predominately couples to inhibitory G protein, Gi/o, and MCHR2 can only couple to Gq/11. Here we present cryo-electron microscopy structures of MCH-activated MCHR1 with Gi and MCH-activated MCHR2 with Gq at the global resolutions of 3.01 Å and 2.40 Å, respectively. These structures reveal that MCH adopts a consistent cysteine-mediated hairpin loop configuration when bound to both receptors. A central arginine from the LGRVY core motif between the two cysteines of MCH penetrates deeply into the transmembrane pocket, triggering receptor activation. Integrated with mutational and functional insights, our findings elucidate the molecular underpinnings of ligand recognition and MCH receptor activation and offer a structural foundation for targeted drug design.

17.
J Agric Food Chem ; 72(14): 8225-8236, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38557068

RESUMEN

As a continuous flow investigation of novel pesticides from natural quinolizidine alkaloids, the chemical compositions of the seeds of Sophora alopecuroides were thoroughly researched. Fifteen new aloperine-type alkaloids (1-15) as well as six known aloperine-type alkaloids (16-21) were obtained from the extract of S. alopecuroides. The structures of 1-21 were confirmed via HRESIMS, NMR, UV, IR, ECD calculations, and X-ray diffraction. The antiviral activities of 1-21 against tobacco mosaic virus (TMV) were detected following the improved method of half-leaf. Compared with ningnanmycin (protective: 69.7% and curative: 64.3%), 15 exhibited excellent protective (71.7%) and curative (64.6%) activities against TMV. Further biological studies illustrated that 15 significantly inhibited the transcription of the TMV-CP gene and increased the activities of polyphenol oxidase (PPO), peroxidase (POD), superoxide dismutase (SOD), and phenylalanine ammonia-lyase (PAL). The antifungal activities of 1-21 against Phytophythora capsica, Botrytis cinerea, Alternaria alternata, and Gibberella zeae were screened according to a mycelial inhibition test. Compound 13 displayed excellent antifungal activity against B. cinerea (EC50: 7.38 µg/mL). Moreover, in vitro antifungal mechanism studies displayed that 13 causes accumulation of reactive oxygen species and finally leads to mycelia cell membrane damage and cell death in vitro.


Asunto(s)
Alcaloides , Quinolizidinas , Sophora , Virus del Mosaico del Tabaco , Antifúngicos , Sophora/química , Alcaloides/química , Antivirales/farmacología , Antivirales/química , Semillas/química
18.
Front Microbiol ; 15: 1298262, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38567072

RESUMEN

Introduction: Dietary nutrient content is crucial for energy metabolism and development of gut microbiota. Herein, this study aimed to explore the effects of fat-to-fiber ratios on nutrient transporter, energy metabolism and gut microbiota when ingredients composition was altered. Methods: A total of 240 as-hatched broiler chickens were randomly assigned into three groups including low fat-high dietary fiber (LF-HD), medium fat-medium dietary fiber (MF-MD) and high fat-low dietary fiber (HF-LD), with diets being iso-protein, and broilers were offered the same commercial diets from 21 to 42 d. The data were analyzed using one-way ANOVA of SPSS. Results and Discussion: Results showed that HF-LD diet significantly increased glucose content and decreased triglyceride in serum of broilers (p < 0.05). The mRNA abundance of jejunal gene involved in glucose transporter and tricarboxylic acid (TCA) cycle was significantly increased in broilers fed with HF-LD diets. Compared with LF-HD, HF-LD had a lower abundance of Anaerofilum and CHKCI001, and an increased proportion of beneficial bacteria such as Alistipes, Catenibacillus, Intestinimonas, Lactobacillus, and Peptococcus (p < 0.05). Functional prediction of these microbial changes indicated that HF-LD diet drove caecal microbiota to participate in carbohydrate metabolism and TCA cycle (p < 0.05). Dietary HF-LD-induced microbiota changes were positively correlated with growth performance of broilers (p < 0.05). Therefore, HF-LD diet increased glucose transporters and energy metabolism in intestine and shaped microbial structure and metabolic pathways, which may benefit the growth performance of broilers.

19.
Nutr J ; 23(1): 39, 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38520010

RESUMEN

BACKGROUND: Modifying diet is crucial for diabetes and complication management. Numerous studies have shown that adjusting eating habits to align with the circadian rhythm may positively affect metabolic health. However, eating midpoint, eating duration, and their associations with diabetic kidney disease (DKD) are poorly understood. METHODS: The National Health and Nutrition Examination Survey (2013-2020) was examined for information on diabetes and dietary habits. From the beginning and ending times of each meal, we calculated the eating midpoint and eating duration. Urinary albumin-to-creatinine ratio (UACR) ≥ 30 mg/g and/or estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2 were the specific diagnostic criteria for DKD. RESULTS: In total, details of 2194 subjects with diabetes were collected for analysis. The overall population were divided into four subgroups based on the eating midpoint quartiles. The prevalence of DKD varied noticeably (P = 0.037) across the four categories. When comparing subjects in the second and fourth quartiles of eating midpoint to those in the first one, the odds ratios (ORs) of DKD were 1.31 (95% CI, 1.03 to 1.67) and 1.33 (95% CI, 1.05 to 1.70), respectively. And after controlling for potential confounders, the corresponding ORs of DKD in the second and fourth quartiles were 1.42 (95% CI, 1.07 to 1.90) and 1.39 (95% CI, 1.04 to 1.85), respectively. CONCLUSIONS: A strong correlation was found between an earlier eating midpoint and a reduced incidence of DKD. Eating early in the day may potentially improve renal outcomes in patients with diabetes.


Asunto(s)
Diabetes Mellitus Tipo 2 , Nefropatías Diabéticas , Humanos , Nefropatías Diabéticas/epidemiología , Nefropatías Diabéticas/etiología , Nefropatías Diabéticas/metabolismo , Encuestas Nutricionales , Estudios Transversales , Riñón , Tasa de Filtración Glomerular , Diabetes Mellitus Tipo 2/complicaciones
20.
Food Chem ; 446: 138763, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38428077

RESUMEN

Calcium deficiency is prone to fractures, osteoporosis and other symptoms. In this study, sheep bone protein hydrolysates (SBPHs) were obtained by protease hydrolysis. A low-calcium-diet-induced calcium-deficiency rat model was established to investigate the effects of SBPHs on calcium absorption and intestinal flora composition. The results showed that an SBPHs + CaCl2 treatment significantly increased the bone calcium content, bone mineral density, trabecular bone volume, and trabecular thickness, and reduced trabecular separation, and changed the level of bone turnover markers (P < 0.05). Supplementation of SBPHs + CaCl2 can remarkably enhance the bone mechanical strength, and the microstructure of bone was improved, and the trabecular network was more continuous, complete, and thicker. Additionally, SBPHs + CaCl2 dietary increased the abundance of Firmicutes and reduced the abundance of Proteobacteria and Verrucomicrobiota, and promoted the production of short chain fatty acids. This study indicated that SBPHs promoted calcium absorption and could be applied to alleviate osteoporosis.


Asunto(s)
Calcio , Osteoporosis , Ratas , Animales , Ovinos , Calcio/metabolismo , Hidrolisados de Proteína/farmacología , Cloruro de Calcio/farmacología , Calcio de la Dieta , Densidad Ósea , Osteoporosis/metabolismo , Dieta
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