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1.
Mol Biol Evol ; 41(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38174583

RESUMO

Bioluminescence in beetles has long fascinated biologists, with diverse applications in biotechnology. To date, however, our understanding of its evolutionary origin and functional variation mechanisms remains poor. To address these questions, we obtained high-quality reference genomes of luminous and nonluminous beetles in 6 Elateroidea families. We then reconstructed a robust phylogenetic relationship for all luminous families and related nonluminous families. Comparative genomic analyses and biochemical functional experiments suggested that gene evolution within Elateroidea played a crucial role in the origin of bioluminescence, with multiple parallel origins observed in the luminous beetle families. While most luciferase-like proteins exhibited a conserved nonluminous amino acid pattern (TLA346 to 348) in the luciferin-binding sites, luciferases in the different luminous beetle families showed divergent luminous patterns at these sites (TSA/CCA/CSA/LVA). Comparisons of the structural and enzymatic properties of ancestral, extant, and site-directed mutant luciferases further reinforced the important role of these sites in the trade-off between acyl-CoA synthetase and luciferase activities. Furthermore, the evolution of bioluminescent color demonstrated a tendency toward hypsochromic shifts and variations among the luminous families. Taken together, our results revealed multiple parallel origins of bioluminescence and functional divergence within the beetle bioluminescent system.


Assuntos
Besouros , Animais , Humanos , Besouros/genética , Filogenia , Sequência de Aminoácidos , Luciferases/genética , Luciferases/química , Luciferases/metabolismo , Sítios de Ligação
2.
Curr Issues Mol Biol ; 46(4): 2884-2925, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38666911

RESUMO

At present, the occurrence of a large number of infectious and non-communicable diseases poses a serious threat to human health as well as to drug development for the treatment of these diseases. One of the most significant challenges is finding new drug candidates that are therapeutically effective and have few or no side effects. In this respect, the active compounds in medicinal plants, especially flavonoids, are potentially useful compounds with a wide range of pharmacological activities. They are naturally present in nature and valuable in the treatment of many infectious and non-communicable diseases. Flavonoids are divided into fourteen categories and are mainly derived from plant extraction, chemical synthesis and structural modification, and biosynthesis. The structural modification of flavonoids is an important way to discover new drugs, but biosynthesis is currently considered the most promising research direction with the potential to revolutionize the new production pipeline in the synthesis of flavonoids. However, relevant problems such as metabolic pathway analyses and cell synthesis protocols for flavonoids need to be addressed on an urgent basis. In the present review, new research techniques for assessing the biological activities of flavonoids and the mechanisms of their biological activities are elucidated and their modes of interaction with other drugs are described. Moreover, novel drug delivery systems, such as nanoparticles, bioparticles, colloidals, etc., are gradually becoming new means of addressing the issues of poor hydrophilicity, lipophilicity, poor chemical stability, and low bioavailability of flavonoids. The present review summarizes the latest research progress on flavonoids, existing problems with their therapeutic efficacy, and how these issues can be solved with the research on flavonoids.

3.
Cancer ; 130(1): 18-30, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37682730

RESUMO

BACKGROUND: Immunotherapy (IO) has demonstrated promising results in treating extensive-stage small cell lung cancer (ES-SCLC), and the management of ES-SCLC brain metastases (BMs) is now receiving significant clinical attention. The objective of this study was to evaluate the role of IO in the clinical management of BMs. METHODS: Between January 2020 and December 2021, the study included the records of 250 patients who were diagnosed with ES-SCLC. Overall survival (OS), progression-free survival, intracranial progression-free survival, and the cumulative incidence of BMs were calculated using the Kaplan-Meier method and were compared using the log-rank test. In addition, the Cox regression model was used to analyze prognostic factors. RESULTS: In the entire group, 85 patients had baseline BMs (IO plus chemotherapy [IO + ChT], n = 38; ChT alone, n = 47), and 165 patients (IO + ChT, n = 86; ChT alone, n = 79) did not have BMs at the time of initial diagnosis. The median follow-up was 22.4 months. The OS benefit with first-line antiprogrammed death ligand 1 therapy was maintained regardless of whether patients had BMs (with BMs, 17.97 vs. 13.14 months [p = .03]; without BMs, 18.46 vs. 15.05 months [p = .047]). However, in patients without BMs, IO did not delay the median time to developing brain progression (10.84 vs. 10.74 months; p = .84), and it did not significantly reduce the risk of developing intracranial metastases (the 2-year actuarial risk of developing BMs was 57.0% vs. 50.6%, respectively). CONCLUSIONS: Antiprogrammed death ligand 1 therapy improved OS regardless of the presence of BMs. However, IO did not delay the median time to brain progression or reduce the risk of intracranial metastasis in patients without baseline BMs. The findings of this study have important clinical implications for the future management of BMs from ES-SCLC.


Assuntos
Neoplasias Encefálicas , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Neoplasias Pulmonares/patologia , Estudos Retrospectivos , Ligantes , Neoplasias Encefálicas/secundário
4.
Anal Chem ; 96(21): 8791-8799, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38742926

RESUMO

MicroRNAs (miRNAs) are novel tumor biomarkers owing to their important physiological functions in cell communication and the progression of multiple diseases. Due to the small molecular weight, short sequence length, and low concentration levels of miRNA, miRNA detection presents substantial challenges, requiring the advancement of more refined and sensitive techniques. There is an urgent demand for the development of a rapid, user-friendly, and sensitive miRNA analysis method. Here, we developed an enhanced biotin-streptavidin dual-mode phase imaging surface plasmon resonance (PI-SPR) aptasensor for sensitive and rapid detection of miRNA. Initially, we evaluated the linear sensing range for miRNA detection across two distinct sensing modalities and investigated the physical factors that influence the sensing signal in the aptamer-miRNA interaction within the PI-SPR aptasensor. Then, an enhanced biotin-streptavidin amplification strategy was introduced in the PI-SPR aptasensor, which effectively reduced the nonspecific adsorption by 20% and improved the limit of detection by 548 times. Furthermore, we have produced three types of tumor marker chips, which utilize the rapid sensing mode (less than 2 min) of PI-SPR aptasensor to achieve simultaneous detection of multiple miRNA markers in the serum from clinical cancer patients. This work not only developed a new approach to detect miRNA in different application scenarios but also provided a new reference for the application of the biotin-streptavidin amplification system in the detection of other small biomolecules.


Assuntos
Aptâmeros de Nucleotídeos , Biotina , MicroRNAs , Estreptavidina , Ressonância de Plasmônio de Superfície , MicroRNAs/análise , MicroRNAs/sangue , Biotina/química , Ressonância de Plasmônio de Superfície/métodos , Estreptavidina/química , Humanos , Aptâmeros de Nucleotídeos/química , Limite de Detecção , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/análise , Técnicas Biossensoriais/métodos
5.
Phys Rev Lett ; 132(13): 138401, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38613297

RESUMO

Chirality is an essential nature of biological systems. However, it remains obscure how the handedness at the microscale is translated into chiral morphogenesis at the tissue level. Here, we investigate three-dimensional (3D) tissue morphogenesis using an active fluid theory invoking chirality. We show that the coordination of achiral and chiral stresses, arising from microscopic interactions and energy input of individual cells, can engender the self-organization of 3D papillary and helical structures. The achiral active stress drives the nucleation of asterlike topological defects, which initiate 3D out-of-plane budding, followed by rodlike elongation. The chiral active stress excites vortexlike topological defects, which favor the tip spheroidization and twisting of the elongated rod. These results unravel the chiral morphogenesis observed in our experiments of 3D organoids generated by human embryonic stem cells.


Assuntos
Divisão Celular , Humanos , Morfogênese
6.
Langmuir ; 40(2): 1524-1533, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38166436

RESUMO

The development of universal anode materials with superlative electrochemical performance poses a great challenge for rechargeable alkali metal (AM) ion battery technologies. In the present work, the viability of the gapless Dirac t-BN (tetragonal boron nitride) monolayer as a lightweight binder-free anode has been systematically evaluated via comprehensive first-principles calculations. Aside from the desirable electronic conductivity, the t-BN monolayer exhibits an excellent ionic conductivity as well due to its moderate affinity for Li, Na, and K atoms with favorable in-plane barriers of 0.36, 0.18, and 0.19 eV, respectively. Meanwhile, the presence of B4N4 octagons allows the AM atoms to penetrate through the t-BN monolayer. Excitingly, the host material delivers an ultrahigh specific capacity up to 1080 mA h g-1 for Li, 5400 mA h g-1 for Na, and 2160 mA h g-1 for K in the wake of low mean open-circuit voltages of 0.033, 0.203, and 0.300 V at the half-cell level. According to the standard hydrogen electrode methodology, the energy densities are forecasted to be as large as 3240, 13500, and 5680 mW h g-1 for Li, Na, and K ion batteries, respectively, with robust thermal stability up to at least 400 K. The safety and cycling durability of the t-BN monolayer are jointly corroborated via the moderate mechanical strengths and ab initio molecular dynamics simulations at the maximum intercalated states, as well as via the small lattice changes and its ultrahigh tolerable ultimate tensile strain. These findings unambiguously promise that the t-BN monolayer can serve as an appealing candidate for anode applications in AM ion batteries.

7.
Angew Chem Int Ed Engl ; : e202408574, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38859545

RESUMO

All-solid-state potassium batteries emerge as promising alternatives to lithium batteries, leveraging their high natural abundance and cost-effectiveness. Developing potassium solid electrolytes (SEs) with high room-temperature ionic conductivity is critical for realizing efficient potassium batteries. In this study, we present the synthesis of K2.98Sb0.91S3.53Cl0.47, showcasing a room-temperature ionic conductivity of 0.32 mS/cm and a low activation energy of 0.26 eV. This represents an increase of over two orders of magnitude compared to the parent compound K3SbS4, marking the highest reported ionic conductivity for non-oxide potassium SEs. Solid-state 39K magic-angle-spinning nuclear magnetic resonance on K2.98Sb0.91S3.53Cl0.47 reveals an increased population of mobile K+ ions with fast dynamics. Ab initio molecular dynamics (AIMD) simulations further confirm a delocalized K+ density and significantly enhanced K+ diffusion. This work demonstrates diversification of the anion sublattice as an effective approach to enhance ion transport and highlights K2.98Sb0.91S3.53Cl0.47 as a promising SE for all-solid-state potassium batteries.

8.
J Am Chem Soc ; 145(42): 23227-23237, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37843005

RESUMO

The synthesis and application of three-dimensional (3D) mesoporous covalent-organic frameworks (COFs) are still to be developed. Herein, two mesoporous 3D COFs with an stp topology were synthesized in a highly crystalline form with aniline as the modulator. The chemical composition of these COFs was confirmed by Fourier transform infrared (FT-IR) and 13C cross-polarization magic angle spinning nuclear magnetic resonance (NMR) spectroscopies. These 3D mesoporous COFs were highly crystalline and exhibited permanent porosity and good chemical stability in both aqueous and organic media. The space group and unit cell parameters of COF HFPTP-TAE were verified by powder X-ray diffraction (PXRD), small-angle X-ray scattering, and three-dimensional electron diffraction (3D ED). The appropriate pore size of the COF HFPTP-TAE facilitated the inclusion of enzyme lipase PS with a loading amount of 0.28 g g-1. The lipase⊂HFPTP-TAE (⊂ refers to "include in") composite exhibited high catalytic activity, good thermal stability, and a wide range of solvent tolerance. Specifically, it could catalyze the alcoholysis of aspirin methyl ester (AME) with high catalytic efficiency. Oriented one-dimensional (1D) channel mesopores in HFPTP-TAE accommodated lipase, meanwhile preventing them from aggregation, while windows on the wall of the 1D channel favored molecular diffusion; thus, this COF-enzyme design outperformed its amorphous isomer, two-dimensional (2D) mesoporous COF, 3D mesoporous COF with limited crystallinity, and mesoporous silica as an enzyme host.

9.
Biochem Biophys Res Commun ; 665: 71-77, 2023 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-37149985

RESUMO

People of all ages could suffer from sleep disorders, which are increasingly recognized as common manifestations of neurologic disease. Acorus tatarinowii is a herb that has been used in traditional medicine to promote sleep. ß-asarone, as the main component of volatile oil obtained from Acorus tatarinowii, may be the main contributor to the sleeping-promoting efficacy of Acorus tatarinowii. In the study, adult male C57BL/6 mice were administered ß-asarone at 12.5 mg/kg, 25 mg/kg, and 50 mg/kg. Behavioral experiments showed that ß-asarone at 25 mg/kg could significantly improve sleep duration. It was also observed that the proportion of NREM (Non-Rapid Eye Movement) sleep increased considerably after administration of ß-asarone. In the PVN (paraventricular nucleus of hypothalamus) region of the hypothalamus, it was observed that the glutamate content decreased after ß-asarone treatment. At the same time, the expression of VGLUT2 (vesicular glutamate transporters 2) decreased while the expression of GAD65 (glutamic acid decarboxylase 65) and GABARAP (GABA Type A Receptor-Associated Protein) increased in the hypothalamus, suggesting that ß-asarone may suppress arousal by reducing glutamate and promoting transformation of glutamate to the inhibitory neurotransmitter GABA (γ-aminobutyric acid). This study is the first to focus on the association between ß-asarone and sleep, shedding perspectives for pharmacological applications of ß-asarone and providing a new direction for future research.


Assuntos
Ácido Glutâmico , Núcleo Hipotalâmico Paraventricular , Masculino , Camundongos , Animais , Camundongos Endogâmicos C57BL , Sono , Anisóis/farmacologia , Ácido gama-Aminobutírico
10.
Phys Rev Lett ; 130(18): 181901, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37204899

RESUMO

We demonstrate the recently proposed nucleon energy-energy correlator (NEEC) f_{EEC}(x,θ) can unveil the gluon saturation in the small-x regime in eA collisions. The novelty of this probe is that it is fully inclusive just like the deep-inelastic scattering (DIS), with no requirements of jets or hadrons but still provides an evident portal to the small-x dynamics through the shape of the θ distribution. We find that the saturation prediction is significantly different from the expectation of the collinear factorization.

11.
J Nutr ; 153(9): 2561-2570, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37543214

RESUMO

BACKGROUND: In early life, sialic acid (SA) plays a crucial role in neurodevelopment and neuronal function. However, it remains unclear whether and how SA supplementation in early life promotes behavioral response to stress in adolescence. OBJECTIVES: This study aimed to examine the effects and mechanisms of SA on the antistress capability under challenging situations. METHODS: In this study, C57BL/6 mice were daily supplemented with 1 µL SA solution/g body weight at the dose of 10 mg/kg/d from postnatal day (PND) 5-45. The antistress behaviors, including open field, elevated plus maze, forced swimming test, and tail suspension test, were performed at PND 46, PND 48, PND 50, and PND 52 to detect the antistress ability of SA, respectively. RESULTS: Our results showed that SA-treated mice were more active in facing challenging situations. The fiber photometry experiment showed that SA promoted the excitatory neuronal response in the medial prefrontal cortex (mPFC), which was extensively interconnected to stress. Besides, electrophysiological results revealed SA enhanced synaptic transmission rather than neuronal excitability of mPFC excitatory neurons. It was also supported by the increasing spine density of mPFC excitatory neurons. At the molecular amount, the SA elevated the transmitter release-related proteins of mPFC, including Synapsin 1 and vesicular glutamate transporter 1 (VGlut 1). Furthermore, SA supplementation enhanced synaptic transmission mainly by altering the kinetics of synaptic transmission. CONCLUSIONS: The SA supplementation enhanced the response capability to stress under challenging situations, and the enhanced synaptic transmission of mPFC excitatory neurons may be the neurological basis of active response under challenging situations. In general, our findings suggested that SA supplementation in early life can promote stress resistance in adolescence.


Assuntos
Ácido N-Acetilneuramínico , Transmissão Sináptica , Camundongos , Animais , Ácido N-Acetilneuramínico/farmacologia , Camundongos Endogâmicos C57BL , Transmissão Sináptica/fisiologia , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia
12.
Biotechnol Bioeng ; 120(7): 1784-1796, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37203999

RESUMO

Chondroitin sulfate A (CSA) is a valuable glycosaminoglycan that has great market demand. However, current synthetic methods are limited by requiring the expensive sulfate group donor 3'-phosphoadenosine-5'-phosphosulfate (PAPS) and inefficient enzyme carbohydrate sulfotransferase 11 (CHST11). Herein, we report the design and integration of the PAPS synthesis and sulfotransferase pathways to realize whole-cell catalytic production of CSA. Using mechanism-based protein engineering, we improved the thermostability and catalytic efficiency of CHST11; its Tm and half-life increased by 6.9°C and 3.5 h, respectively, and its specific activity increased 2.1-fold. Via cofactor engineering, we designed a dual-cycle strategy of regenerating ATP and PAPS to increase the supply of PAPS. Through surface display engineering, we realized the outer membrane expression of CHST11 and constructed a whole-cell catalytic system of CSA production with an 89.5% conversion rate. This whole-cell catalytic process provides a promising method for the industrial production of CSA.


Assuntos
Sulfatos de Condroitina , Fosfoadenosina Fosfossulfato , Sulfatos de Condroitina/metabolismo
13.
Arch Insect Biochem Physiol ; 112(4): e21997, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36656761

RESUMO

We sequenced and analyzed the transcriptomes from different tissues of the soldier beetle, Podabrus annulatus (Coleoptera: Cantharidae), and obtained 75.74 Gb clean reads which were assembled into 95,274 unigenes. Among these transcripts, 25,484 unigenes of highly quality were annotated. Based on annotation and tBLASTn results, we identified a total of 101 candidate olfactory-related genes for the first time, including 11 putative odorant-binding proteins (OBPs), 6 chemosensory proteins (CSP), 50 olfactory receptors (ORs), 25 gustatory receptors (GRs), 6 ionotropic receptors (IRs), and 3 sensory neuron membrane proteins (SNMPs). BLASTX best-hit results indicated that these chemosensory genes were most identical to their respective orthologs from Photinus pyralis. Phylogenetic analyses also revealed that the ORs, GRs, and IRs of Podabrus annulatus are closely related to those of Photinus pyralis. The fragment per kilobase per million mapped fragments (FPKM) values showed that the PannOBP2, PannOBP3, and PannOBP10 were predominantly expressed in the antennae, PannOBP1 in the abdomen-thorax, while others were not identified to be tissue-specific. These olfactory-related differentially expressed genes (DEGs) demonstrated different roles in the olfactory system of Podabrus annulatus. This study establishes the groundwork for future research into the molecular mechanism of olfactory recognition in Podabrus annulatus.


Assuntos
Besouros , Receptores Odorantes , Animais , Transcriptoma , Besouros/genética , Besouros/metabolismo , Perfilação da Expressão Gênica , Filogenia , Olfato , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Antenas de Artrópodes/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo
14.
Ecotoxicol Environ Saf ; 259: 115034, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37210999

RESUMO

Bisphenol A (BPA), a well-known environmental endocrine disruptor, has been implicated in anxiety-like behavior. But the neural mechanism remains elusive. Herein, we found that mice exposed to 0.5 mg/kg/day BPA chronically from postnatal days (PND) 21 to PND 80 exhibited depression- and anxiety-like behavior. Further study showed that medial prefrontal cortex (mPFC), was associated with BPA-induced depression- and anxiety-like behavior, as evidenced by decreased c-fos expression in mPFC of BPA-exposed mice. Both the morphology and function of glutamatergic neurons (also called pyramidal neurons) in mPFC of mice were impaired following BPA exposure, characterized by reduced primary branches, weakened calcium signal, and decreased mEPSC frequency. Importantly, optogenetic activation of the pyramidal neurons in mPFC greatly reversed BPA-induced depression- and anxiety-like behavior in mice. Furthermore, we reported that microglial activation in mPFC of mice may also have a role in BPA-induced depression- and anxiety-like behavior. Taken together, the results indicated that mPFC is the brain region that is greatly damaged by BPA exposure and is associated with BPA-induced depression- and anxiety-like behavior. The study thus provides new insights into BPA-induced neurotoxicity and behavioral changes.


Assuntos
Depressão , Neurônios , Camundongos , Animais , Depressão/induzido quimicamente , Córtex Pré-Frontal/metabolismo , Ansiedade/induzido quimicamente
15.
Genomics ; 114(2): 110305, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35131472

RESUMO

The subfamily Ototretinae represents an important and unusual lineage of fireflies. Here, we sequenced and annotated three mitogenomes for this subfamily, with two Stenocladius species and one Drilaster species as representatives. The mitogenome of Stenocladius exhibits a rearranged gene order between trnC and trnW caused by transposition, which is a novel finding in Lampyridae. Meanwhile, a long intergenic space (241 to 376 bp) exists between the two rearranged genes, and some remnants (23 bp) of trnW are present within this non-coding region. Moreover, phylogenetic analyses did not recover the monophyly of Ototretinae, in which Drilaster is shown at a basal lineage in Lampyridae, but Stenocladius seems more related to Luciolinae. Therefore, the gene rearrangement in Stenocladius is presumed to result from independent evolutionary events, suggesting that this genus should be placed in a separate lineage. Nevertheless, more representative mitogenomes from different groups are required to verify the present results.


Assuntos
Besouros , Genoma Mitocondrial , Animais , Besouros/genética , Vaga-Lumes/genética , Rearranjo Gênico , Filogenia
16.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 40(3): 418-425, 2023 Jun 25.
Artigo em Zh | MEDLINE | ID: mdl-37380379

RESUMO

The brain-computer interface (BCI) based on motor imagery electroencephalography (MI-EEG) enables direct information interaction between the human brain and external devices. In this paper, a multi-scale EEG feature extraction convolutional neural network model based on time series data enhancement is proposed for decoding MI-EEG signals. First, an EEG signals augmentation method was proposed that could increase the information content of training samples without changing the length of the time series, while retaining its original features completely. Then, multiple holistic and detailed features of the EEG data were adaptively extracted by multi-scale convolution module, and the features were fused and filtered by parallel residual module and channel attention. Finally, classification results were output by a fully connected network. The application experimental results on the BCI Competition IV 2a and 2b datasets showed that the proposed model achieved an average classification accuracy of 91.87% and 87.85% for the motor imagery task, respectively, which had high accuracy and strong robustness compared with existing baseline models. The proposed model does not require complex signals pre-processing operations and has the advantage of multi-scale feature extraction, which has high practical application value.


Assuntos
Encéfalo , Eletroencefalografia , Humanos , Fatores de Tempo , Imagens, Psicoterapia , Redes Neurais de Computação
17.
J Nutr ; 152(11): 2451-2460, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36774111

RESUMO

BACKGROUND: Deoxynivalenol (DON) is a major mycotoxin present in staple foods (particularly in cereal products) that induces intestinal inflammation and disrupts intestinal integrity. Lactoferrin (LF) is a multifunctional protein that contributes to maintaining intestinal homeostasis and improving host health. However, the protective effects of LF on DON-induced intestinal dysfunction remain unclear. OBJECTIVES: This study aimed to investigate the effects of LF on DON-induced intestinal dysfunction in mice, and its underlying protective mechanism. METHODS: Male BALB/c mice (5 wk old) with similar body weights were divided into 4 groups (n = 6/group) and treated as follows for 5 wk: Veh [peroral vehicle daily, commercial (C) diet]; LF (peroral 10 mg LF/d, C diet); DON (Veh, C diet containing 12 mg DON/kg); and LF + DON (peroral 10 mg LF/d, DON diet). Intestinal morphology, tight junction proteins, cytokines, and microbial community were determined. Data were analyzed by 2-factor ANOVA or Kruskal-Wallis test. RESULTS: The DON group exhibited lower final body weight (-12%), jejunal villus height (VH; -41%), and jejunal occludin expression (-36%), and higher plasma IL-1ß concentration (+85%) and jejunal Il1b mRNA expression (+98%) compared with the Veh group (P < 0.05). In contrast, final body weight (+19%), jejunal VH (+49%), jejunal occludin (+53%), and intelectin 1 protein expression (+159%) were greater in LF + DON compared with DON (P < 0.05). Additionally, jejunal Il1b mRNA expression (-31%) and phosphorylation of p38 and extracellular signal regulated kinase 1/2 (-40% and - 38%) were lower in LF + DON compared with DON (P < 0.05). Furthermore, the relative abundance of Clostridium XIVa (+181%) and colonic butyrate concentration (+53%) were greater in LF + DON compared with DON (P < 0.05). CONCLUSIONS: Our study highlights a promising antimycotoxin approach using LF to alleviate DON-induced intestinal dysfunction by modulating the mitogen-activated protein kinase pathway and gut microbial community in mice.


Assuntos
Microbioma Gastrointestinal , Enteropatias , Sistema de Sinalização das MAP Quinases , Tricotecenos , Animais , Masculino , Camundongos , Inflamação/induzido quimicamente , Lactoferrina/farmacologia , Ocludina/genética , RNA Mensageiro , Tricotecenos/toxicidade
18.
Liver Int ; 42(6): 1449-1466, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35184357

RESUMO

BACKGROUND & AIMS: Disruption of lipid metabolism is largely linked to metabolic disorders, such as hypercholesterolemia (HCL) and liver steatosis. While cholesterol metabolic re-programmers can serve as targets for relevant interventions. Here we explored the dietary conjugated linoleic acids (CLA)-induced HCL in mice and the molecular regulation behind it. METHODS: A high dose of CLA supplementation in the diet was used to induce HCL in mice and was found to cause a hyper-activated cholesterol biosynthesis programme in the liver, leading to cholesterol metabolism dysregulation. The effects of a small-molecule drug targeting PPARα, i.e., GW6471 were studied in vivo in mice fed diets with CLA supplementation for 28 days, and in primary hepatocytes derived from HCL-mice in vitro. RESULTS: We demonstrate that CLA induced HCL and liver steatosis through multiple pathways. Among which was the PPARα-mediated cholesterogenesis. It was found to cooperate with SREBP2 via binding to Hmgcr and Dhcr7 (genes encoding key enzymes of the cholesterol biosynthetic pathway) and recruits the histone marks H3K27ac and H3K4me1 and cofactors. PPARα inhibition disrupts its physical association with SREBP2 by blocking cobinding of PPARα and SREBP2 to the genomic DNA response element. We showed that NR RORγ functions as an essential mediator that facilitates the interaction of PPARα and SREBP2 to modulate the cholesterol biosynthesis genes expression. CONCLUSIONS: Our study unravels that the small-molecule compound GW6471 exerts an attractive therapeutic effect for CLA-induced HCL, involving multiple pathways with the "PPARα-RORγ-SREBP2" being a potential complex player in this hepatic cholesterol biosynthesis programming.


Assuntos
Fígado Gorduroso , Hipercolesterolemia , Hiperlipidemias , Ácidos Linoleicos Conjugados , Animais , Colesterol/metabolismo , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/metabolismo , Humanos , Hipercolesterolemia/tratamento farmacológico , Hipercolesterolemia/metabolismo , Ácidos Linoleicos Conjugados/metabolismo , Ácidos Linoleicos Conjugados/farmacologia , Metabolismo dos Lipídeos , Fígado/metabolismo , Camundongos , PPAR alfa
19.
AAPS PharmSciTech ; 23(5): 163, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35680728

RESUMO

In recent years, the oral administration of vinorelbine has gradually replaced intravenous administration in the treatment of several types of tumors. Even though the risk of phlebitis is avoided with oral administration, oral vinorelbine is still not a highly patient-compliant route due to the severe gastrointestinal toxicity. Vinorelbine-loaded liposomes with high encapsulation efficiency and suitable particle size were prepared using the ammonium sulfate gradient method. Chitosan-coated liposomes showed the slowest in vitro release compared to uncoated liposomes and vinorelbine solution. No damage was observed in the intestinal epithelial cells of mice orally administered with coated vinorelbine liposomes due to the low presence of the free drug in the gastrointestinal tract and the LD50 was increased from 129.83 to 182.25 mg/kg compared to oral vinorelbine solution. In addition, the positive surface potential of chitosan-coating endowed liposomes with mucosal adhesive function, delaying the time to reach the peak plasma concentration of vinorelbine from 1 to 4 h after administration. And bioavailability was increased to 2.1-fold compared to vinorelbine solution. In short, a new strategy to address the severe gastrointestinal side effects of oral vinorelbine has been developed.


Assuntos
Quitosana , Lipossomos , Administração Oral , Animais , Disponibilidade Biológica , Camundongos , Vinorelbina
20.
J Cell Physiol ; 236(6): 4387-4402, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33184849

RESUMO

Nonalcoholic-fatty-liver-disease (NAFLD) is the result of imbalances in hepatic lipid partitioning and is linked to dietary factors. We demonstrate that conjugated linoleic acid (CLA) when given to mice as a dietary supplement, induced an enlarged liver, hepatic steatosis, and increased plasma levels of fatty acid (FA), alanine transaminase, and triglycerides. The progression of NAFLD and insulin resistance was reversed by GW6471 a small-molecule antagonist of peroxisome proliferator-activated receptor α (PPARα). Transcriptional profiling of livers revealed that the genes involved in FA oxidation and lipogenesis as two core gene programs controlled by PPARα in response to CLA and GW6471 including Acaca and Acads. Bioinformatic analysis of PPARα ChIP-seq data set and ChIP-qPCR showed that GW6471 blocks PPARα binding to Acaca and Acads and abolishes the PPARα-mediated local histone modifications of H3K27ac and H3K4me1 in CLA-treated hepatocytes. Thus, our findings reveal a dual role of PPARα in the regulation of lipid homeostasis and highlight its druggable nature in NAFLD.


Assuntos
Ácidos Graxos/metabolismo , Hepatócitos/metabolismo , Lipogênese , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , PPAR alfa/metabolismo , Acetil-CoA Carboxilase/genética , Acetil-CoA Carboxilase/metabolismo , Acil-CoA Desidrogenase/genética , Acil-CoA Desidrogenase/metabolismo , Animais , Células Cultivadas , Modelos Animais de Doenças , Regulação Enzimológica da Expressão Gênica , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Histonas/metabolismo , Resistência à Insulina , Ácidos Linoleicos Conjugados , Lipogênese/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Oxazóis/farmacologia , Oxirredução , PPAR alfa/antagonistas & inibidores , PPAR alfa/genética , Transdução de Sinais , Ativação Transcricional , Tirosina/análogos & derivados , Tirosina/farmacologia
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