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1.
Angew Chem Int Ed Engl ; : e202320223, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38588224

RESUMO

Structurally ordered soft materials that respond to complementary stimuli are susceptible to control over their spatial and temporal morphostructural configurations via intersectional or combined effects such as gating, feedback, shape-memory, or programming. In absence of general and robust design and prediction strategies for their mechanical properties, at present, combined chemical and crystal engineering approaches could provide useful guidelines to identify effectors that determine both the magnitude and time of their response. Here, we capitalize on the purported ability of soft intermolecular interactions to instigate mechanical compliance by using halogenation to elicit both mechanical and photochemical activity of organic crystals. Starting from (E)-1,4-diphenylbut-2-ene-1,4-dione, whose crystals are brittle and photoinert, we use double and quadruple halogenation to introduce halogen-bonded planes that become interfaces for molecular gliding, rendering the material mechanically and photochemically plastic. Fluorination diversifies the mechanical effects further, and crystals of the tetrafluoro derivative are also elastic but also motile, displaying the rare photosalient effect.

2.
R Soc Open Sci ; 11(4): 230976, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38601036

RESUMO

Visual mimicry is less understood in birds than in other taxa. The interspecific social dominance mimicry (ISDM) hypothesis asserts that subordinate species resemble dominant ones to reduce aggression. Plumage mimicry has also been consistently noted in mixed-species flocks (MSFs), suggesting a connection to grouping behaviour, although it is unclear whether this is linked to ISDM. We studied greater necklaced laughingthrush (GNLT, Pterorhinus pectoralis) and lesser necklaced laughingthrush (LNLT, Garrulax monileger), which were recently placed in different genera. Measurements of 162 museum specimens showed LNLT converging in sympatry with GNLT in necklace colour, but diverging in necklace to body ratio, with proportionally smaller necklaces. The species were closely associated in six of seven MSF systems from Nepal to China. In a study of foraging behaviour in Nepal, aggression was rare between the species, LNLT followed GNLT and had lower foraging rates when further from GNLT. Our data suggest a link between this MSF-associated mimicry and ISDM, and that the subordinate LNLT may be the mimic and gain more from the resemblance. The species spend much time together in dense and poorly lit vegetation, where the LNLTs resemblance to GNLTs potentially allows them to forage closer to GNLTs than would be otherwise possible.

3.
Front Physiol ; 15: 1324924, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38645693

RESUMO

Purpose: The effects of the combination of strength training and acupuncture on chronic ankle instability have not been studied. This study examined effects of strength training combined with acupuncture on balance ability, ankle motion perception, and muscle strength in chronic ankle instability among college students. Methods: Forty-six chronic ankle instability college students were randomly categorized into the experimental group (n = 24, strength training + acupuncture) and the control group (n = 22, strength training) for an 8-week intervention. Results: For the results at 8 weeks, compared with the baseline, in the experimental group, the chronic Ankle Instability Tool (CAIT) score, ankle dorsiflexion, plantar flex, eversion peak torque (60°/s), and plantar flex peak torque (180°/s) increased by 13.7%, 39.4%, 13.7%, 14.2%, and 12.3%, respectively. Dorsiflexion, plantar flexion, inversion, and eversion kinesthetic sensation test angles decreased by 17.4%, 20.6%, 15.0%, and 17.2%, respectively. Anterior-posterior and medial-lateral displacement, and anterior-posterior and medial-lateral velocity decreased by 28.9%, 31.6%, 33.3%, and 12.4%, respectively. Anterior-posterior and medial-lateral displacement, and anterior-posterior and medial-lateral mean velocity decreased by 28.9%, 31.6%, 33.3%, and 12.4%, respectively. In the control group, the Cumberland Ankle Instability Tool score and the ankle dorsiflexion peak torque (60°/s) increased by 13.8% and 17.9%, respectively. The inversion kinesthetic sensation test angle decreased by 15.2%, whereas anterior-posterior and medial-lateral displacement, and anterior-posterior and medial-lateral mean velocity decreased by 17.1%, 29.4%, 12.3%, and 16.8%, respectively. 2) For the comparison between the groups after 8 weeks, the values of ankle dorsiflexion and plantar flex peak torque (60°/s) in the experimental group were greater than those in the control group. The values of ankle plantar flex kinesthetic sensation test angle, the anterior-posterior displacement, and anterior-posterior mean velocity in the experimental group were lower than those in the control group. Conclusion: Acupuncture treatment in conjunction with muscle strength training can further improve the balance ability of anterior-posterior, ankle dorsiflexion, and plantar flex strength and plantar flex motion perception in chronic ankle instability participants.

4.
Gene ; 915: 148410, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38527674

RESUMO

OBJECTIVE: Atherosclerosis (AS) is the primary cause of deadly cardio-cerebro vascular diseases globally. This study aims to explore the key differentially expressed genes (DEGs), potentially serving as predictive biomarkers for AS. METHODS: Microarray datasets were retrieved from the GEO database for DEGs and DE-miRNAs identification. Then biological function of DEGs were elucidated based on gene ontology (GO) and KEGG pathway enrichment analysis. The protein-protein interaction (PPI) network and DEGs-DE-miRNAs network were constructed, with emphasis on hub DEGs selection and their interconnections. Additionally, receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic precision of hub DEGs for AS. More importantly, an AS Syrian Golden hamster model was established to validate the expression levels of hub DEGs in AS. RESULTS: A total of 203 DEGs and 10 DE-miRNAs were screened, with six genes were chosen as hub DEGs. These DEGs were significantly enriched in AS-related biological processes and pathways, such as immune and inflammatory response, cellular response to IL-1 and TNF, positive regulation of angiogenesis, Type I diabetes mellitus, Cytokine-cytokine receptor interaction, TLR signaling pathway. Also, these DEGs and DE-miRNAs formed a closely-interacted DE-miRNAs - DEGs - KEGG pathway network. Besides, hub DEGs presented promising diagnostic potential for AS (AUC: 0.781 âˆ¼ 0.887). In addition, the protein expression levels of TNF-α, CXCL8, CCL4, IL-1ß, CCL3 and CCR8 were significantly increased in AS group Syrian Golden hamsters. CONCLUSION: The identified candidate genes TNF, CXCL8, CCL4, IL1B, CCL3 and CCR8 may have the potential to serve as prognostic biomarker in diagnosing AS.

5.
Comput Biol Med ; 172: 108209, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38460313

RESUMO

Halogenation is an indispensable method in the structural modification of lead compounds. It is known to increase lipophilicity and is hence used to improve membrane permeability and thus bioavailability. In this study, we compare the water solubility (logS) of organohalogen compounds and their non-halogenated parent compounds using the molecular matched pair (MMP) analysis method. Unexpectedly, 19.9% of the compounds increased their water solubility upon halogenation. Iodination was observed to have the greatest effect on solubility, followed by chlorination, bromination, and fluorination. Introducing amino, hydroxyl and carboxyl groups into organohalogens improves their aqueous solubilities, whereas introducing a trifluoromethyl group has the opposite effect. According to our quantum chemical calculations, the increased water solubility upon halogenation is, at least partially, attributed to an increased polarity and polarizability. These results improve our understanding of the influence of halogenation on bioactivity.


Assuntos
Halogenação , Hidrocarbonetos Fluorados , Solubilidade , Água
6.
Biomed Pharmacother ; 173: 116402, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38471277

RESUMO

Oleanolic acid (OA) is previously shown to exert bone protective effects in aged animals. However, its role in regulating osteoblastic vitamin D bioactivation, which is one of major causes of age-related bone loss, remains unclear. Our results revealed that treatment of OA significantly increased skeletal CYP27B1 expression and circulating 1,25(OH)2D3 in ovariectomized mice (p <0.01). Moreover, OA upregulated CYP27B1 protein expression and activity, as well as the vitamin D-responsive bone markers alkaline phosphatase (ALP) activity and osteopontin (OPN) protein expression, in human osteoblast-like MG-63 cells (p<0.05). CYP27B1 expression increased along with the osteoblastic differentiation of human bone marrow derived mesenchymal stem cells (hMSCs). CYP27B1 expression and cellular 1,25(OH)2D3 production were further potentiated by OA in cells at mature osteogenic stages. Notably, our study suggested that the osteogenic actions of OA were CYP27B1 dependent. In summary, the bone protective effects of OA were associated with the induction of CYP27B1 activity and expression in bone tissues and osteoblastic lineages. Hence, OA might be a potential approach for management of age-related bone loss.


Assuntos
Anabolizantes , Ácido Oleanólico , Osteoporose , Vitamina D/análogos & derivados , Humanos , Animais , Camundongos , Idoso , 25-Hidroxivitamina D3 1-alfa-Hidroxilase/metabolismo , Ácido Oleanólico/farmacologia , Vitamina D/farmacologia , Vitamina D/metabolismo , Osso e Ossos/metabolismo , Vitaminas
7.
J Med Chem ; 67(6): 4782-4792, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38502551

RESUMO

Halogen bonds (XBs) are essential noncovalent interactions in molecular recognition and drug design. Current studies on XBs in drug design mainly focus on the interactions between halogenated ligands and target proteins, lacking a systematic study of naturally existing and artificially prepared halogenated residue XBs (hr_XBs) and their characteristics. Here, we conducted a computational study on the potential hr_XBs in proteins/peptides using database searching, quantum mechanics calculations, and molecular dynamics simulations. XBs at the protein-peptide interaction interfaces are found to enhance their binding affinity. Additionally, the formation of intramolecular XBs (intra_XBs) within proteins may significantly contribute to the structural stability of structurally flexible proteins while having a minor impact on proteins with inherently high structural rigidity. Impressively, introducing halogens without the formation of intra_XBs may lead to a decrease in the protein structural stability. This study enriches our understanding of the roles and effects of halogenated residue XBs in biological systems.


Assuntos
Halogênios , Proteínas , Halogênios/química , Proteínas/metabolismo , Peptídeos/metabolismo , Simulação de Dinâmica Molecular , Ligação Proteica
8.
iScience ; 27(3): 109163, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38425841

RESUMO

Doxorubicin (Dox) poses a considerable threat to patients owing to its cardiotoxicity, thus limiting its clinical utility. Optimal cardioprotective intervention strategies are needed to suppress tumor growth but also minimize cardiac side effects. Here, we showed that tragus vagus nerve stimulation (tVNS) improved the imbalanced autonomic tone, ameliorated impaired cardiac function and fibrosis, attenuated myocyte apoptosis, and mitochondrial dysfunction compared to those in the Dox group. The beneficial effects were attenuated by methyllycaconitine citrate (MLA). The transcript profile revealed that there were 312 differentially expressed genes and the protection of tVNS and retardation of MLA were related to inflammatory response and NADPH oxidase activity. In addition, tVNS synergizing with Dox inhibited tumor growth and lung metastasis and promoted apoptosis of tumor cells in an anti-tumor immunity manner. These results indicated that non-invasive neuromodulation can play a dual role in preventing Dox-induced cardiotoxicity and suppressing tumor growth through inflammation and oxidative stress.

9.
Curr Zool ; 70(1): 34-44, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38476134

RESUMO

Participants in mixed-species bird flocks (MSFs) have been shown to associate with species that are similar in body size, diet, and evolutionary history, suggesting that facilitation structures these assemblages. In addition, several studies have suggested that species in MSFs resemble each other in their plumage, but this question has not been systematically investigated for any MSF system. During the nonbreeding season of 2020 and 2021, we sampled 585 MSFs on 14 transects in 2 habitats of Tongbiguang Nature Reserve in western Yunnan Province, China. We performed social network analysis and the Multiple Regression Quadratic Assignment Procedure to evaluate the effect of 4 species traits (body size, overall plumage color, distinctive plumage patterns, and diet) and evolutionary history on species association strength at the whole-MSF and within-MSF levels. All 41 significant relationships showed that species with stronger associations were more similar in their various traits. Body size had the strongest effect on association strength, followed by phylogeny, plumage patterns, and plumage color; diet had the weakest effect. Our results are consistent with the hypotheses that the benefits of associating with phenotypically similar species outweigh the potential costs of interspecific competition, and that trait matching can occur in plumage characteristics, albeit more weakly than in other traits. Several explanations exist as to why similarities in plumage may occur in MSFs, including that they could reduce predators' ability to target phenotypically "odd" individuals. Whether trait matching in plumage occurs through assortative processes in ecological time or is influenced by co-evolution requires further study.

10.
Funct Plant Biol ; 512024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38326230

RESUMO

Phytohormones play a key role in regulating tiller number. Ascorbic acid (Asc)-phytohormone interaction plays a pivotal role in the regulation of senescence. We analysed the relationship between Asc and the enzyme concentrations and gene transcript abundances related to the signal perception of strigolactones (SLs), the contents of four phytohormones (abscisic acid, ABA; jasmonic acid, JA; indole acetic acid, IAA; cytokinin, CTK), the enzyme concentrations and gene transcript abundances related to the synthesis or transportation of these four phytohormones. Our results showed that Asc deficiency leads to the upregulation of enzyme concentrations, gene transcript abundances related to the SL signal perception, ABA synthesis and IAA transport. The altered level of Asc also leads to a change in the contents of ABA, JA, IAA and CTK. These findings support the conclusion that Asc or Asc/DHA play an important role in the signal perception and transduction of SLs, and Asc may affect the coordinated regulation of SL, IAA and CTK on rice (Oryza sativa ) tillering.


Assuntos
Compostos Heterocíclicos com 3 Anéis , Lactonas , Oryza , Reguladores de Crescimento de Plantas , Ácido Ascórbico , Percepção
11.
Int J Biol Macromol ; 262(Pt 1): 130017, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38336333

RESUMO

Sustainably sourced lignin presents great potential as a green feedstock for fertilizer production but commercial fulfillment is still challenging owing to the mediocre fertilizer activity of lignin. To address this issue, an effective strategy to enhance the activity of lignin-based potassium fertilizer (LPF) is proposed through lignin fractionation. Three lignin fractions subdivided from enzymatic hydrolysis lignin (EHL) were adopted as the feedstock for LPF preparation, and the effect of lignin fractionation on wheat seed germination and seedling growth was investigated. Compared with the potassium fertilizer from unfractionated lignin, LPF-F1 showed significantly improved effects on promoting seed germination and seedling growth, which can be attributed to the high potassium content resulted from its abundant phenolic hydroxyl and carboxyl contents. Under the optimal treatment concentration (100 mg/L), LPF-F1 showed comparable promotion effect to commercial fulvic acid potassium on wheat seedling growth, suggesting the potential of LPF-F1 as commercial potassium fertilizer. Overall, this work reveals that lignin heterogeneity presents critical effects on the wheat seed germination and seedling growth of LPF, and the fertilizer activity of LPF can be substantially improved using fractionated lignin with low molecular weight as the raw material.


Assuntos
Lignina , Plântula , Lignina/farmacologia , Germinação , Triticum , Fertilizantes , Hidrólise , Sementes
12.
Phytomedicine ; 126: 155254, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38342016

RESUMO

BACKGROUND: The gut-brain axis (GBA) plays a central role in cerebral ischaemia-reperfusion injury (CIRI). Rhubarb, known for its purgative properties, has demonstrated protective effects against CIRI. However, it remains unclear whether this protective effect is achieved through the regulation of the GBA. AIM: This study aims to investigate the mechanism by which rhubarb extract improves CIRI by modulating the GBA pathway. METHODS: We identified the active components of rhubarb extract using LC-MS/MS. The model of middle cerebral artery occlusion (MCAO) was established to evaluate the effect of rhubarb extract. We conducted 16S rDNA sequencing and untargeted metabolomics to analyze intestinal contents. Additionally, we employed HE staining, TUNEL staining, western blot, and ELISA to assess intestinal barrier integrity. We measured the levels of inflammatory cytokines in serum via ELISA. We also examined blood-brain barrier (BBB) integrity using Evans blue (EB) penetration, transmission electron microscopy (TEM), western blot, and ELISA. Neurological function scores and TTC staining were utilized to evaluate neurological outcomes. RESULTS: We identified twenty-six active components in rhubarb. Rhubarb extract enhanced α-diversity, reduced the abundance of Enterobacteriaceae, and partially rectified metabolic disorders in CIRI rats. It also ameliorated pathological changes, increased the expressions of ZO-1, Occludin, and Claudin 1 in the colon, and reduced levels of LPS and d-lac in serum. Furthermore, it lowered the levels of IL-1ß, IL-6, IL-10, IL-17, and TNF-α in serum. Rhubarb extract mitigated BBB dysfunction, as evidenced by reduced EB penetration and improved hippocampal microstructure. It upregulated the expressions of ZO-1, Occludin, Claudin 1, while downregulating the expressions of TLR4, MyD88, and NF-κB. Similarly, rhubarb extract decreased the levels of IL-1ß, IL-6, and TNF-α in the hippocampus. Ultimately, it reduced neurological function scores and cerebral infarct volume. CONCLUSION: Rhubarb effectively treats CIRI, potentially by inhibiting harmful bacteria, correcting metabolic disorders, repairing intestinal barrier function, alleviating BBB dysfunction, and ultimately improving neurological outcomes.


Assuntos
Isquemia Encefálica , Doenças Metabólicas , Fármacos Neuroprotetores , Traumatismo por Reperfusão , Rheum , Ratos , Animais , Neuroproteção , Rheum/metabolismo , Ocludina/metabolismo , Interleucina-6 , Fator de Necrose Tumoral alfa/genética , Eixo Encéfalo-Intestino , Cromatografia Líquida , Claudina-1 , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Espectrometria de Massas em Tandem , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/patologia , Azul Evans/uso terapêutico , Traumatismo por Reperfusão/metabolismo , Doenças Metabólicas/tratamento farmacológico , Infarto da Artéria Cerebral Média/tratamento farmacológico
13.
Stem Cell Res Ther ; 15(1): 35, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38321505

RESUMO

BACKGROUND: Spinal cord injury (SCI) is a devastating disease that causes extensive damage to oligodendrocytes and neurons leading to demyelination and axonal degeneration. In this study, we co-transplanted cell grafts containing oligodendrocyte progenitor cells (OPCs) derived from human-induced pluripotent stem cells (iPSCs) combined with human umbilical vein endothelial cells (HUVECs), which were reported to promote OPCs survival and migration, into rat contusion models to promote functional recovery after SCI. METHODS: OPCs were derived from iPSCs and identified by immunofluorescence at different time points. Functional assays in vitro were performed to evaluate the effect of HUVECs on the proliferation, migration, and survival of OPCs by co-culture and migration assay, as well as on the neuronal axonal growth. A combination of OPCs and HUVECs was transplanted into the rat contusive model. Upon 8 weeks, immunofluorescence staining was performed to test the safety of transplanted cells and to observe the neuronal repairment, myelination, and neural circuit reconstruction at the injured area; also, the functional recovery was assessed by Basso, Beattie, and Bresnahan open-field scale, Ladder climb, SEP, and MEP. Furthermore, the effect of HUVECs on grafts was also determined in vivo. RESULTS: Data showed that HUVECs promote the proliferation, migration, and survival of OPCs both in vitro and in vivo. Furthermore, 8 weeks upon engraftment, the rats with OPCs and HUVECs co-transplantation noticeably facilitated remyelination, enhanced functional connection between the grafts and the host and promoted functional recovery. In addition, compared with the OPCs-alone transplantation, the co-transplantation generated more sensory neurons at the lesion border and significantly improved the sensory functional recovery. CONCLUSIONS: Our study demonstrates that transplantation of OPCs combined with HUVECs significantly enhances both motor and sensory functional recovery after SCI. No significance was observed between OPCs combined with HUVECs group and OPCs-alone group in motor function recovery, while the sensory function recovery was significantly promoted in OPCs combined with HUVECs groups compared with the other two groups. These findings provide novel insights into the field of SCI research.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células Precursoras de Oligodendrócitos , Traumatismos da Medula Espinal , Ratos , Humanos , Animais , Células Precursoras de Oligodendrócitos/patologia , Células Precursoras de Oligodendrócitos/transplante , Células Endoteliais da Veia Umbilical Humana , Recuperação de Função Fisiológica , Células-Tronco Pluripotentes Induzidas/transplante , Traumatismos da Medula Espinal/patologia , Oligodendroglia , Medula Espinal/patologia , Diferenciação Celular/fisiologia
14.
J Integr Med ; 22(1): 72-82, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38307819

RESUMO

OBJECTIVE: Melittin and its derivative have been developed to support effective gene delivery systems. Their ability to facilitate endosomal release enhances the delivery of nanoparticle-based gene therapy. Nevertheless, its potential application in the context of viral vectors has not received much attention. Therefore, we would like to optimize the rAAV vector by Melittin analog to improve the transduction efficiency of rAAV in liver cancer cells and explore the mechanism of Melittin analog on rAAV. METHODS: Various melittin-derived peptides were inserted into loop VIII of the capsid protein in recombinant adeno-associated virus vectors. These vectors carrying either gfp or fluc genes were subjected to quantitative polymerase chain reaction assays and transduction assays in human embryonic kidney 293 (HEK293T) cells to investigate the efficiency of vector production and gene delivery. In addition, the ability of a specific p5RHH-rAAV vector to deliver genes was examined through in vitro transduction of different cultured cells and in vivo tail vein administration to C57BL/6 mice. Finally, the intricate details of the vector-mediated transduction mechanisms were explored by using pharmacological inhibitors of every stage of the rAAV2 intracellular life cycle. RESULTS: A total of 76 melittin-related peptides were identified from existing literature. Among them, CMA-3, p5RHH and aAR3 were found to significantly inhibit transduction of rAAV2 vector crude lysate. The p5RHH-rAAV2 vectors efficiently transduced not only rAAV-potent cell lines but also cell lines previously considered resistant to rAAV. Mechanistically, bafilomycin A1, a vacuolar endosome acidification inhibitor, completely inhibited the transgene expression mediated by the p5RHH-rAAV2 vectors. Most importantly, p5RHH-rAAV8 vectors also increased hepatic transduction in vivo in C57BL/6 mice. CONCLUSION: The incorporation of melittin analogs into the rAAV capsids results in a significant improvement in rAAV-mediated transgene expression. While further modifications remain an area of interest, our studies have substantially broadened the pharmacological prospects of melittin in the context of viral vector-mediated gene delivery. Please cite this article as: Meng J, He Y, Yang H, Zhou L, Wang S, Feng X, Al-shargi OY, Yu X, Zhu L, Ling, C. Melittin analog p5RHH enhances recombinant adeno-associated virus transduction efficiency. J Integr Med. 2024; 22(1): 72-82.


Assuntos
Dependovirus , Meliteno , Camundongos , Masculino , Animais , Humanos , Dependovirus/genética , Meliteno/farmacologia , Meliteno/genética , Transdução Genética , Células HEK293 , Camundongos Endogâmicos C57BL , Vetores Genéticos
15.
Cytotechnology ; 76(1): 97-111, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38304623

RESUMO

Blocking the CXCL12/CXCR4 axis can alter the biological functions of leukaemia cells. We hypothesise that interleukin (IL)-8 and IL-6 play an important role in this process. To test this hypothesis, we established a co-culture model of leukaemia cells and bone marrow stromal cells. Treatment of cells with AMD3100, a CXCR4 antagonist, and G-CSF blocked the CXCL12/CXCR4 axis, inducing biological changes in the leukaemia cells and altering IL-8 and IL-6 levels. Subsequently, after stimulating the CXCL12/CXCR4 axis, specific pathway blockers were employed to assess the role of four candidate signalling pathways in this process. ELISA results confirmed that MG-132 (10 µm) inhibits IL-8 expression and that the NF-κB signalling pathway contributes to this effect. Moreover, treatment with Perifosine, an AKT inhibitor, inhibited IL-6 expression. In addition, changes in the NF-κB signalling pathway inhibited IL-8 expression. Treatment with SP600125, a Jun N-terminal kinase inhibitor, and Perifosine also inhibited IL-8 expression; however, this effect occurred later. IL-6 expression was also lower in the Perifosine group; hence, inhibiting the PI3K/AKT signalling pathway can reduce IL-6 expression. This process requires the participation of multiple signalling pathways to regulate IL-8 and IL-6 expression. Therefore, the associated mechanism is likely to be highly intricate, with potential cross-effects that may impact leukaemia pathogenesis. IL-6 and IL-8 are physiologically regulated by the CXCL12/CXCR4 axis, while the NF-κB and JNK/AP-1 pathways are required for IL-8 expression in T-cell acute lymphoblastic leukaemia. Accordingly, by upregulating IL-8, the bone marrow microenvironment and CXCL12/CXCR4 axis may contribute to T-cell acute lymphoblastic leukaemia pathogenesis.

16.
J Chem Inf Model ; 64(3): 724-736, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38206320

RESUMO

Continuous exploration of the chemical space of molecules to find ligands with high affinity and specificity for specific targets is an important topic in drug discovery. A focus on cyclic compounds, particularly natural compounds with diverse scaffolds, provides important insights into novel molecular structures for drug design. However, the complexity of their ring structures has hindered the applicability of widely accepted methods and software for the systematic identification and classification of cyclic compounds. Herein, we successfully developed a new method, D3Rings, to identify acyclic, monocyclic, spiro ring, fused and bridged ring, and cage ring compounds, as well as macrocyclic compounds. By using D3Rings, we completed the statistics of cyclic compounds in three different databases, e.g., ChEMBL, DrugBank, and COCONUT. The results demonstrated the richness of ring structures in natural products, especially spiro, macrocycles, and fused and bridged rings. Based on this, three deep generative models, namely, VAE, AAE, and CharRNN, were trained and used to construct two data sets similar to DrugBank and COCONUT but 10 times larger than them. The enlarged data sets were then used to explore the molecular chemical space, focusing on complex ring structures, for novel drug discovery and development. Docking experiments with the newly generated COCONUT-like data set against three SARS-CoV-2 target proteins revealed that an expanded compound database improves molecular docking results. Cyclic structures exhibited the best docking scores among the top-ranked docking molecules. These results suggest the importance of exploring the chemical space of structurally novel cyclic compounds and continuous expansion of the library of drug-like compounds to facilitate the discovery of potent ligands with high binding affinity to specific targets. D3Rings is now freely available at http://www.d3pharma.com/D3Rings/.


Assuntos
Proteínas , Software , Simulação de Acoplamento Molecular , Proteínas/química , Desenho de Fármacos , Descoberta de Drogas , Compostos Orgânicos
17.
Nat Ecol Evol ; 8(2): 251-266, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38182682

RESUMO

The biodiversity impacts of agricultural deforestation vary widely across regions. Previous efforts to explain this variation have focused exclusively on the landscape features and management regimes of agricultural systems, neglecting the potentially critical role of ecological filtering in shaping deforestation tolerance of extant species assemblages at large geographical scales via selection for functional traits. Here we provide a large-scale test of this role using a global database of species abundance ratios between matched agricultural and native forest sites that comprises 71 avian assemblages reported in 44 primary studies, and a companion database of 10 functional traits for all 2,647 species involved. Using meta-analytic, phylogenetic and multivariate methods, we show that beyond agricultural features, filtering by the extent of natural environmental variability and the severity of historical anthropogenic deforestation shapes the varying deforestation impacts across species assemblages. For assemblages under greater environmental variability-proxied by drier and more seasonal climates under a greater disturbance regime-and longer deforestation histories, filtering has attenuated the negative impacts of current deforestation by selecting for functional traits linked to stronger deforestation tolerance. Our study provides a previously largely missing piece of knowledge in understanding and managing the biodiversity consequences of deforestation by agricultural deforestation.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Filogenia , Florestas , Agricultura
18.
Circ Res ; 134(3): 290-306, 2024 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-38197258

RESUMO

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is the most prevalent monogenic heart disorder. However, the pathogenesis of HCM, especially its nongenetic mechanisms, remains largely unclear. Transcription factors are known to be involved in various biological processes including cell growth. We hypothesized that SP1 (specificity protein 1), the first purified TF in mammals, plays a role in the cardiomyocyte growth and cardiac hypertrophy of HCM. METHODS: Cardiac-specific conditional knockout of Sp1 mice were constructed to investigate the role of SP1 in the heart. The echocardiography, histochemical experiment, and transmission electron microscope were performed to analyze the cardiac phenotypes of cardiac-specific conditional knockout of Sp1 mice. RNA sequencing, chromatin immunoprecipitation sequencing, and adeno-associated virus experiments in vivo were performed to explore the downstream molecules of SP1. To examine the therapeutic effect of SP1 on HCM, an SP1 overexpression vector was constructed and injected into the mutant allele of Myh6 R404Q/+ (Myh6 c. 1211C>T) HCM mice. The human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) from a patient with HCM were used to detect the potential therapeutic effects of SP1 in human HCM. RESULTS: The cardiac-specific conditional knockout of Sp1 mice developed a typical HCM phenotype, displaying overt myocardial hypertrophy, interstitial fibrosis, and disordered myofilament. In addition, Sp1 knockdown dramatically increased the cell area of hiPSC-CMs and caused intracellular myofibrillar disorganization, which was similar to the hypertrophic cardiomyocytes of HCM. Mechanistically, Tuft1 was identified as the key target gene of SP1. The hypertrophic phenotypes induced by Sp1 knockdown in both hiPSC-CMs and mice could be rescued by TUFT1 (tuftelin 1) overexpression. Furthermore, SP1 overexpression suppressed the development of HCM in the mutant allele of Myh6 R404Q/+ mice and also reversed the hypertrophic phenotype of HCM hiPSC-CMs. CONCLUSIONS: Our study demonstrates that SP1 deficiency leads to HCM. SP1 overexpression exhibits significant therapeutic effects on both HCM mice and HCM hiPSC-CMs, suggesting that SP1 could be a potential intervention target for HCM.


Assuntos
Cardiomiopatia Hipertrófica , Células-Tronco Pluripotentes Induzidas , Humanos , Camundongos , Animais , Células-Tronco Pluripotentes Induzidas/metabolismo , Cardiomiopatia Hipertrófica/metabolismo , Miofibrilas/metabolismo , Miócitos Cardíacos/metabolismo , Cardiomegalia/metabolismo , Fatores de Transcrição/metabolismo , Mamíferos
19.
Nat Ecol Evol ; 8(3): 552-563, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38238436

RESUMO

The geographic expansion of Homo sapiens populations into southeastern Europe occurred by ∼47,000 years ago (∼47 ka), marked by Initial Upper Palaeolithic (IUP) technology. H. sapiens was present in western Siberia by ∼45 ka, and IUP industries indicate early entries by ∼50 ka in the Russian Altai and 46-45 ka in northern Mongolia. H. sapiens was in northeastern Asia by ∼40 ka, with a single IUP site in China dating to 43-41 ka. Here we describe an IUP assemblage from Shiyu in northern China, dating to ∼45 ka. Shiyu contains a stone tool assemblage produced by Levallois and Volumetric Blade Reduction methods, the long-distance transfer of obsidian from sources in China and the Russian Far East (800-1,000 km away), increased hunting skills denoted by the selective culling of adult equids and the recovery of tanged and hafted projectile points with evidence of impact fractures, and the presence of a worked bone tool and a shaped graphite disc. Shiyu exhibits a set of advanced cultural behaviours, and together with the recovery of a now-lost human cranial bone, the record supports an expansion of H. sapiens into eastern Asia by about 45 ka.


Assuntos
Fósseis , Crânio , Humanos , China , Europa (Continente) , Antropologia Cultural
20.
Basic Res Cardiol ; 119(1): 75-91, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38172251

RESUMO

Mast cells (MCs) are important intermediates between the nervous and immune systems. The cardiac autonomic nervous system (CANS) crucially modulates cardiac electrophysiology and arrhythmogenesis, but whether and how MC-CANS neuroimmune interaction influences arrhythmia remain unclear. Our clinical data showed a close relationship between serum levels of MC markers and CANS activity, and then we use mast cell stabilizers (MCSs) to alter this MC-CANS communication. MCSs, which are well-known anti-allergic agents, could reduce the risk of ventricular arrhythmia (VA) after myocardial infarction (MI). RNA-sequencing (RNA-seq) analysis to investigate the underlying mechanism by which MCSs could affect the left stellate ganglion (LSG), a key therapeutic target for modulating CANS, showed that the IL-6 and γ-aminobutyric acid (GABA)-ergic system may be involved in this process. Our findings demonstrated that MCSs reduce VA risk along with revealing the potential underlying antiarrhythmic mechanisms.


Assuntos
Antialérgicos , Estabilizadores de Mastócitos , Humanos , Neuroimunomodulação , Arritmias Cardíacas/prevenção & controle , Coração
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