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1.
Insects ; 15(4)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38667360

RESUMO

Mountain ecosystems harbor evolutionarily unique and exceptionally rich biodiversity, particularly in insects. In this study, we characterized the diversity, community stability, and assembly mechanisms of butterflies on a subtropical mountain in the Chebaling National Nature Reserve, Guangdong Province, China, using grid-based monitoring across the entire region for two years. The results showed that species richness, abundance, and Faith's phylogenetic diversity decreased with increasing elevation; taxonomic diversity played a considerable role in mediating the effects of environmental changes on stability. Moreover, our results showed that stochastic processes are dominant in governing the assembly of butterfly communities across all elevational gradients, with habitats at an elevation of 416-580 m subjected to the strongest stochastic processes, whereas heterogeneous selection processes displayed stronger effects on the assembly of butterfly communities at 744-908 m, 580-744 m, and 908-1072 m, with abiotic factors inferred as the main driving forces. In addition, significant differences were detected between the barcode tree and the placement tree for the calculated ß-NTI values at 416-580 m. Overall, this study provides new insights into the effects of environmental change on the stability and assembly of butterflies in Chebaling, which will be beneficial for biodiversity conservation and policy development.

2.
Indian J Dermatol ; 69(1): 57-62, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38572045

RESUMO

Warts are caused by human papillomavirus (HPV) infection and can involve multiple parts of skin and mucosa, of which periungual and subungual warts are the most difficult to treat. Periungual or subungual wart is verruca vulgaris growing around or under the fingernail, destroying and deforming the nail and nail bed. Currently, liquid nitrogen cryotherapy and CO2 laser are often used for the treatment. Clinically, few doctors routinely use photodynamic therapy (PDT) to treat viral warts. We used PDT combined with liquid nitrogen cryotherapy and curettage to successfully treat a case of intractable periungual and subungual warts.

3.
BMC Cardiovasc Disord ; 24(1): 223, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658849

RESUMO

BACKGROUND: Long-term exposure to a high altitude environment with low pressure and low oxygen could cause abnormalities in the structure and function of the heart. Myocardial strain is a sensitive indicator for assessing myocardial dysfunction, monitoring myocardial strain is of great significance for the early diagnosis and treatment of high altitude heart-related diseases. This study applies cardiac magnetic resonance tissue tracking technology (CMR-TT) to evaluate the changes in left ventricular myocardial function and structure in rats in high altitude environment. METHODS: 6-week-old male rats were randomized into plateau hypoxia rats (plateau group, n = 21) as the experimental group and plain rats (plain group, n = 10) as the control group. plateau group rats were transported from Chengdu (altitude: 360 m), a city in a plateau located in southwestern China, to the Qinghai-Tibet Plateau (altitude: 3850 m), Yushu, China, and then fed for 12 weeks there, while plain group rats were fed in Chengdu(altitude: 360 m), China. Using 7.0 T cardiac magnetic resonance (CMR) to evaluate the left ventricular ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV) and stroke volume (SV), as well as myocardial strain parameters including the peak global longitudinal (GLS), radial (GRS), and circumferential strain (GCS). The rats were euthanized and a myocardial biopsy was obtained after the magnetic resonance imaging scan. RESULTS: The plateau rats showed more lower left ventricular GLS and GRS (P < 0.05) than the plain rats. However, there was no statistically significant difference in left ventricular EDV, ESV, SV, EF and GCS compared to the plain rats (P > 0.05). CONCLUSIONS: After 12 weeks of exposure to high altitude low-pressure hypoxia environment, the left ventricular global strain was partially decreased and myocardium is damaged, while the whole heart ejection fraction was still preserved, the myocardial strain was more sensitive than the ejection fraction in monitoring cardiac function.


Assuntos
Altitude , Volume Sistólico , Função Ventricular Esquerda , Animais , Masculino , Ratos Sprague-Dawley , Doença da Altitude/fisiopatologia , Doença da Altitude/diagnóstico por imagem , Valor Preditivo dos Testes , Imagem Cinética por Ressonância Magnética , Imageamento por Ressonância Magnética , Fatores de Tempo , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologia , Ratos , Hipóxia/fisiopatologia
4.
Ecol Evol ; 14(4): e11218, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38606343

RESUMO

Insects harbor a remarkable diversity of gut microbiomes critical for host survival, health, and fitness, but the mechanism of this structured symbiotic community remains poorly known, especially for the insect group consisting of many closely related species that inhabit the Qinghai-Tibet Plateau. Here, we firstly analyzed population-level 16S rRNA microbial dataset, comprising 11 Parnassius species covering 5 subgenera, from 14 populations mostly sampled in mountainous regions across northwestern-to-southeastern China, and meanwhile clarified the relative importance of multiple factors on gut microbial community structure and evolution. Our findings indicated that both host genetics and larval host plant modulated gut microbial diversity and community structure. Moreover, the effect analysis of host genetics and larval diet on gut microbiomes showed that host genetics played a critical role in governing the gut microbial beta diversity and the symbiotic community structure, while larval host plant remarkably influenced the functional evolution of gut microbiomes. These findings of the intimate insect-microbe-plant interactions jointly provide some new insights into the correlation among the host genetic background, larval host plant, the structure and evolution of gut microbiome, as well as the mechanisms of high-altitude adaptation in closely related species of this alpine butterfly group.

5.
Materials (Basel) ; 17(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38473590

RESUMO

Transition metals and their oxide compounds exhibit excellent chemical reactivity; however, their easy agglomeration and high cost limit their catalysis applications. In this study, an interpolation structure of a Myriophyllum verticillatum L. biochar-supported Mn/Mg composite (Mn/Mg@MV) was prepared to degrade triphenyl phosphate (TPhP) from wastewater through the activating periodate (PI) process. Interestingly, the Mn/Mg@MV composite showed strong radical self-producing capacities. The Mn/Mg@MV system degraded 93.34% TPhP (pH 5, 10 µM) within 150 min. The experimental results confirmed that the predominant role of IO3· and the auxiliary ·OH jointly contributed to the TPhP degradation. In addition, the TPhP pollutants were degraded to various intermediates and subsequent Mg mineral phase mineralization via mechanisms like interfacial processes and radical oxidation. DFT theoretical calculations further indicated that the synergy between Mn and Mg induced the charge transfer of the carbon-based surface, leading to the formation of an ·OH radical-enriched surface and enhancing the multivariate interface process of ·OH, IO3, and Mn(VII) to TPhP degradation, resulting in the further formation of Mg PO4 mineralization.

6.
Polymers (Basel) ; 16(6)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38543453

RESUMO

Herein, wheat straw residue and pulping waste liquid were collected from pulping mill and mixed to prepare bio-based granular fuels by using compression molding technology, and to explore the comprehensive utilization of the industrial waste of pulping and papermaking. The effects of pulping waste liquid on granular fuel properties were analyzed systemically. Further study of the function of pulping waste liquid, cellulose and hemicellulose was used to replace wheat straw residue and avoid the interference factors. Therefore, the prediction models of granular fuels were established with influencing factors that included cellulose, hemicellulose and pulping waste liquid. The granular fuels had the best performance with 18.30% solid content of pulping waste liquid. The highest transverse compressive strength of granular fuel was 102.61 MPa, and the activation energy was 81.71 KJ·mol-1. A series of curve fitting prediction models were established to clarify the forming process of granular fuel, and it turned out that the pulping waste liquid could improve the adhesion between solid particles and increase their compression resistance.

7.
Postgrad Med J ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38497290

RESUMO

PURPOSE: (i) To analyze age-adjusted incidence rates of synchronous bone metastases diagnosed alongside primary malignancy from 2010 to 2018 in the US population, (ii) determine the incidence proportions (IPs) and characteristics of synchronous bone metastases among newly diagnosed cancer patients in the USA especially pediatric cases, and (iii) assess the implications of synchronous bone metastases on cancer patient's survival, and identify the survival risk factors for these cancer patients. METHODS: Utilizing data from the Surveillance, Epidemiology, and End Results (SEER) program (2010-2018), we calculated age-adjusted IPs and annual percentage change (APC), and employed logistic regression and Cox regression models for our analysis. RESULTS: 3 300 736 cancer patients were identified. The age-adjusted incidence rates of synchronous bone metastases increased from 2010 (18.04/100 000) to 2018 (20.89/100 000; APC: 2.3, 95% confidence interval [CI], 1.4-3.1), but decreased in lung cancer (average APC: -1.0, 95% CI, -1.8 to -0.3). The highest IPs were observed in pediatric neuroblastoma (43.2%; 95% CI, 39.8%-46.7%) and adult small cell carcinoma (23.1%; 95% CI, 22.7%-23.4%). Multivariate logistic analyses revealed that primary tumor characteristics were correlated with higher bone metastases risk. Survival analyses also showed varied prognostic outcomes based on metastasis sites and demographics among cancer patients. Landmark analyses further indicated among long-term cancer survivors (≥3 and ≥5 years), patients with de novo bone metastases had the poorest survival rates compared with those with other synchronous metastases (P < 0.001). CONCLUSION: This study provides a population-based estimation of the incidence and prognosis for synchronous bone metastases. Our findings highlight the need for early identification of high-risk groups and multidisciplinary approaches to improve prognosis of cancer patients with de novo bone metastases.

8.
J Nat Med ; 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427210

RESUMO

This study investigates the cardioprotective effects of Paeoniflorin (PF) on left ventricular remodeling following acute myocardial infarction (AMI) under conditions of hypobaric hypoxia. Left ventricular remodeling post-AMI plays a pivotal role in exacerbating heart failure, especially at high altitudes. Using a rat model of AMI, the study aimed to evaluate the cardioprotective potential of PF under hypobaric hypoxia. Ninety male rats were divided into four groups: sham-operated controls under normoxia/hypobaria, an AMI model group, and a PF treatment group. PF was administered for 4 weeks after AMI induction. Left ventricular function was assessed using cardiac magnetic resonance imaging. Biochemical assays of cuproptosis, oxidative stress, apoptosis, inflammation, and fibrosis were performed. Results demonstrated PF significantly improved left ventricular function and remodeling after AMI under hypobaric hypoxia. Mechanistically, PF decreased FDX1/DLAT expression and serum copper while increasing pyruvate. It also attenuated apoptosis, inflammation, and fibrosis by modulating Bcl-2, Bax, NLRP3, and oxidative stress markers. Thus, PF exhibits therapeutic potential for left ventricular remodeling post-AMI at high altitude by inhibiting cuproptosis, inflammation, apoptosis and fibrosis. Further studies are warranted to optimize dosage and duration and elucidate PF's mechanisms of action.

9.
Neuroscience ; 542: 33-46, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38354901

RESUMO

The forkhead box protein P2 (Foxp2), initially identified for its role in speech and language development, plays an important role in neural development. Previous studies investigated the function of the Foxp2 gene by deleting or mutating Foxp2 from developmental stages. Little is known about its physiological function in adult brains. Although Foxp2 has been well studied in the dorsal striatum, its function in the nucleus accumbens (NAc) of the ventral striatum remains elusive. Here, we examine the physiological function of Foxp2 in NAc of mouse brains. We conditionally knocked out Foxp2 by microinjections of AAV-EGFP-Cre viruses into the medial shell of NAc of Foxp2 floxed (cKO) mice. Immunostaining showed increased c-Fos positive cells in cKO NAc at basal levels, suggesting an abnormality in Foxp2-deficient NAc cells. Unbiased behavioral profiling of Foxp2 cKO mice showed abnormalities in limbic-associated function. Foxp2 cKO mice exhibited abnormal social novelty without preference for interaction with strangers and familiar mice. In appetitive reward learning, Foxp2 cKO mice failed to learn the time expectancy of food delivery. In fear learning, Foxp2 cKO mice exhibited abnormal increases in freezing levels in response to tone paired with foot shock during fear conditioning. The extinction of the fear response was also altered in Foxp2 cKO mice. In contrast, conditional knockout of Foxp2 in NAc did not affect locomotion, motor coordination, thermal pain sensation, anxiety- and depression-like behaviors. Collectively, our study suggests that Foxp2 has a multifaceted physiological role in NAc in the regulation of limbic function in the adult brain.


Assuntos
Aprendizagem , Núcleo Accumbens , Camundongos , Animais , Núcleo Accumbens/metabolismo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Proteínas Repressoras/metabolismo
10.
Phytochemistry ; 220: 114037, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38387725

RESUMO

Five undescribed bisabosqual-type meroterpenoids, bisabosquals E (1) and F (2), stachybisbins J-L (4-6), together with two known ones, were isolated from a novel endophytic fungus KMU22001 within the Stachybotryaceae family. Their structures with absolute configurations were elucidated by detailed interpretation of NMR spectroscopy, mass spectrometry, single-crystal X-ray diffraction and electronic circular dichroism calculations. Compounds 2, 4 and 6 exhibited significant cytotoxicities against five human cancer cell lines with IC50 values ranging from 1.80 ± 0.08 to 17.76 ± 0.97 µM.


Assuntos
Antineoplásicos , Delphinium , Humanos , Estrutura Molecular , Antineoplásicos/farmacologia , Cristalografia por Raios X , Dicroísmo Circular
11.
J Pain Res ; 17: 381-392, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38312505

RESUMO

Objective: To validate whether a residual mass demonstrated on early postoperative MR after percutaneous endoscopic lumbar discectomy (PELD) is indeed an intraoperatively retained annulus fibrosus, and explore the correlation between imaging changes in the residual mass and clinical prognosis of patients. Methods: A prospective study of 118 patients were included. During surgery, a contrast medium, Gadopentetate Dimeglumine, was injected around the ruptured annulus fibrosus. The intensity of the T2 signal, the size of the remaining mass (SR), and the cross-sectional area of the spinal canal (SCSA), VAS, and ODI were assessed at preoperative, 1-h (7-day), 6-month, and 12-month postoperative intervals. Based on VAS at 7 days post-surgery, patients were classified into either a non-remission group (Group A, VAS > 3) or a remission group (Group B, VAS ≤ 3). Results: Six patients who developed recurrent LDH were excluded. A residual mass was detected on MRI 1 h after surgery in 94.6% (106/112). During one year of follow-up, 90.1% (101/112) of the patients displayed fibrous annulus remodeling, although 68.7% (77/112) still exhibited herniation. Significant differences were found in the ODI between Groups A and B one week after surgery (p < 0.001). However, no significant differences were observed in T2 signal intensity, SR, and SCSA at 1-h, 6-month and 12-month post-surgery (p > 0.05) between the two groups. In a multiple linear regression analysis, early postoperative ODI changes were associated with T2 signal (B = -10.22, sig < 0.05), long-term changes were associated with alterations in SR (B = 5.63, sig < 0.05) and SCSA (B = -0.13, sig < 0.05). Conclusion: The residual mass observed in early postoperative MR images after PELD was the retained annulus fibrosus intraoperatively. Short-term changes in clinical symptoms after PELD were linked to T2 signal intensity, while long-term changes were associated with changes in SR and SCSA.

12.
J Agric Food Chem ; 72(6): 2935-2942, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38317284

RESUMO

Sclerotinia stem rot (SSR) caused by the phytopathogenic fungus Sclerotinia sclerotiorum has led to serious losses in the yields of oilseed rape and other crops every year. Here, we designed and synthesized a series of carboxamide derivatives containing a diphenyl ether skeleton by adopting the scaffold splicing strategy. From the results of the mycelium growth inhibition experiment, inhibition rates of compounds 4j and 4i showed more than 80% to control S. sclerotiorum at a dose of 50 µg/mL, which is close to that of the positive control (flubeneteram, 95%). Then, the results of a structure-activity relationship study showed that the benzyl scaffold was very important for antifungal activity and that introducing a halogen atom on the benzyl ring would improve antifungal activity. Furthermore, the results of an in vitro activity test suggested that these novel compounds can inhibit the activity of succinate dehydrogenase (SDH), and the binding mode of 4j with SDH was basically similar to that of the flutolanil derivative. Morphological observation of mycelium revealed that compound 4j could cause a damage on the mycelial morphology and cell structure of S. sclerotiorum, resulting in inhibition of the growth of mycelia. Furthermore, in vivo antifungal activity assessment of 4j displayed a good control of S. sclerotiorum (>97%) with a result similar to that of the positive control at a concentration of 200 mg/L. Thus, the diphenyl ether carboxamide skeleton is a new starting point for the discovery of new SDH inhibitors and is worthy of further development.


Assuntos
Ascomicetos , Brassica napus , Fungicidas Industriais , Antifúngicos/farmacologia , Ascomicetos/metabolismo , Relação Estrutura-Atividade , Brassica napus/metabolismo , Succinato Desidrogenase/metabolismo , Fungicidas Industriais/farmacologia , Fungicidas Industriais/química
13.
bioRxiv ; 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38328117

RESUMO

Neuroblastoma is a leading cause of death in childhood cancer cases. Unlike adult malignancies, which typically develop from aged cells through accumulated damage and mutagenesis, neuroblastoma originates from neural crest cells with disrupted differentiation. This distinct feature provides novel therapeutic opportunities beyond conventional cytotoxic methods. Previously, we reported that the mitochondrial uncoupler NEN (niclosamide ethanolamine) activated mitochondria respiration to reprogram the epigenome, promoting neuronal differentiation. In the current study, we further combine NEN with retinoic acid (RA) to promote neural differentiation both in vitro and in vivo. The treatment increased the expression of RA signaling and neuron differentiation-related genes, resulting in a global shift in the transcriptome towards a more favorable prognosis. Overall, these results suggest that the combination of a mitochondrial uncoupler and the differentiation agent RA is a promising therapeutic strategy for neuroblastoma.

14.
Hepatology ; 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38377452

RESUMO

BACKGROUND AND AIMS: Protein tyrosine sulfation (PTS) is a common posttranslational modification that regulates a variety of physiological and pathological processes. However, the role of PTS in cancer remains poorly understood. The goal of this study was to determine whether and how PTS plays a role in HCC progression. APPROACH AND RESULTS: By mass spectrometry and bioinformatics analysis, we identified SAV1 as a novel substrate of PTS in HCC. Oxidative stress upregulates the transcription of SLC35B2, a Golgi-resident transporter of sulfate donor 3'-phosphoadenosine 5'-phosphosulfate, leading to increased sulfation of SAV1. Sulfation of SAV1 disrupts the formation of the SAV1-MST1 complex, resulting in a decrease of MST1 phosphorylation and subsequent inactivation of Hippo signaling. These molecular events ultimately foster the growth of HCC cells both in vivo and in vitro. Moreover, SLC35B2 is a novel transcription target gene of the Hippo pathway, constituting a positive feedback loop that facilitates HCC progression under oxidative stress. CONCLUSIONS: Our findings reveal a regulatory mechanism of the SLC35B2/SAV1 sulfation axis in response to oxidative stress, highlighting its potential as a promising therapeutic target for HCC.

15.
Nat Plants ; 10(4): 618-632, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38409290

RESUMO

Effector proteins secreted by plant pathogenic fungi are important artilleries against host immunity, but there is no precedent of such effectors being explored as antifungal targets. Here we demonstrate that MoErs1, a species-specific effector protein secreted by the rice blast fungus Magnaporthe oryzae, inhibits the function of rice papain-like cysteine protease OsRD21 involved in rice immunity. Disrupting MoErs1-OsRD21 interaction effectively controls rice blast. In addition, we show that FY21001, a structure-function-based designer compound, specifically binds to and inhibits MoErs1 function. FY21001 significantly and effectively controls rice blast in field tests. Our study revealed a novel concept of targeting pathogen-specific effector proteins to prevent and manage crop diseases.


Assuntos
Proteínas Fúngicas , Oryza , Doenças das Plantas , Oryza/microbiologia , Doenças das Plantas/microbiologia , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Interações Hospedeiro-Patógeno , Papaína/metabolismo , Ascomicetos , Magnaporthe
16.
Genes (Basel) ; 15(2)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38397154

RESUMO

Despite being a non-hematophagous leech, Whitmania pigra is widely used in traditional Chinese medicine for the treatment of antithrombotic diseases. In this study, we provide a high quality genome of W. pigra and based on which, we performed a systematic identification of the potential antithrombotic genes and their corresponding proteins. We identified twenty antithrombotic gene families including thirteen coagulation inhibitors, three platelet aggregation inhibitors, three fibrinolysis enhancers, and one tissue penetration enhancer. Unexpectedly, a total of 79 antithrombotic genes were identified, more than a typical blood-feeding Hirudinaria manillensis, which had only 72 antithrombotic genes. In addition, combining with the RNA-seq data of W. pigra and H. manillensis, we calculated the expression levels of antithrombotic genes of the two species. Five and four gene families had significantly higher and lower expression levels in W. pigra than in H. manillensis, respectively. These results showed that the number and expression level of antithrombotic genes of a non-hematophagous leech are not always less than those of a hematophagous leech. Our study provides the most comprehensive collection of antithrombotic biomacromolecules from a non-hematophagous leech to date and will significantly enhance the investigation and utilization of leech derivatives in thrombosis therapy research and pharmaceutical applications.


Assuntos
Sanguessugas , Trombose , Animais , Humanos , Fibrinolíticos , Sanguessugas/genética , Trombose/genética , Inibidores da Agregação Plaquetária , Cromossomos
17.
Adv Healthc Mater ; : e2400047, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38364079

RESUMO

The presence of multidrug-resistant bacteria has challenged the clinical treatment of bacterial infection. There is a real need for the development of novel biocompatible materials with broad-spectrum antimicrobial activities. Antimicrobial hydrogels show great potential in infected wound healing but are still being challenged. Herein, broad-spectrum antibacterial and mechanically tunable amyloid-based hydrogels based on self-assembly and local mineralization of silver nanoparticles are reported. The mineralized hydrogels are biocompatible and have the advantages of sustained release of silver, prolonged antimicrobial effect, and improved adhesion capacity. Moreover, the mineralized hydrogels display a significant antimicrobial effect against both Gram-positive and Gram-negative bacteria in cells and mice by inducing membrane damage and reactive oxygen species toxicity in bacteria. In addition, the mineralized hydrogels can rapidly accelerate wound healing by the synergy between their antibacterial activity and intrinsic improvement for cell proliferation and migration. This study provides a modular approach to developing a multifunctional protein hydrogel platform based on biomolecule-coordinated self-assembly for a wide range of biomedical applications.

18.
Carbohydr Polym ; 330: 121828, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38368107

RESUMO

Glycoside hydrolases (GHs) are known to depolymerize polysaccharides into oligo-/mono-saccharides, they are extensively used as additives for both animals feed and our food. Here we reported the characterization of IDSGH5-14(CD), a weakly-acidic mesophilic bifunctional mannanase/glucanase of GH5, originally isolated from sheep rumen microbes. Biochemical characterization studies revealed that IDSGH5-14(CD) exhibited preferential hydrolysis of mannan-like and glucan-like substrates. Interestingly, the enzyme exhibited significantly robust catalytic activity towards branched-substrates compared to linear polysaccharides (P < 0.05). Substrate hydrolysis pattern indicated that IDSGH5-14(CD) predominantly liberated oligosaccharides with a degree of polymerization (DP) of 3-7 as the end products, dramatically distinct from canonical endo-acting enzymes. Comparative modeling revealed that IDSGH5-14(CD) was mainly comprised of a (ß/α)8-barrel-like structure with a spacious catalytic cleft on surface, facilitating the enzyme to target high-DP or branched oligosaccharides. Molecular dynamics (MD) simulations further suggested that the branched-ligand, 64-α-D-galactosyl-mannohexose, was steadily accommodated within the catalytic pocket via a two-sided clamp formed by the aromatic residues. This study first reports a bifunctional GH5 enzyme that predominantly generates high-DP oligosaccharides, preferentially from branched-substrates. This provides novel insights into the catalytic mechanism and molecular underpinnings of polysaccharide depolymerization, with potential implications for feed additive development and high-DP oligosaccharides preparation.


Assuntos
Rúmen , beta-Manosidase , Animais , Ovinos , Polimerização , Rúmen/metabolismo , beta-Manosidase/metabolismo , Oligossacarídeos , Polissacarídeos , Glicosídeo Hidrolases/metabolismo , Especificidade por Substrato , Hidrólise
19.
Phytother Res ; 38(3): 1462-1477, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38246696

RESUMO

Reducing mitochondrial oxidative stress has become an important strategy to prevent neuronal death in ischemic stroke. Previous studies have shown that 20(R)-ginsenoside Rg3 can significantly improve behavioral abnormalities, reduce infarct size, and decrease the number of apoptotic neurons in cerebral ischemia/reperfusion injury rats. However, it remains unclear whether 20(R)-ginsenoside Rg3 can inhibit mitochondrial oxidative stress in ischemic stroke and the potential molecular mechanism. In this study, we found that 20(R)-ginsenoside Rg3 notably inhibited mitochondrial oxidative stress in middle cerebral artery occlusion/reperfusion (MCAO/R) rats and maintained the stability of mitochondrial structure and function. Treatment with 20(R)-ginsenoside Rg3 also decreased the levels of mitochondrial fission proteins (Drp1 and Fis1) and increased the levels of fusion proteins (Opa1, Mfn1, and Mfn2) in MCAO/R rats. Furthermore, we found that 20(R)-ginsenoside Rg3 promoted nuclear aggregation of nuclear factor erythroid2-related factor 2 (Nrf2) but did not affect Kelch-like ECH-associated protein-1 (Keap1), resulting in the downstream expression of antioxidants. In in vitro oxygen-glucose deprivation/reperfusion stroke models, the results of PC12 cells treated with 20(R)-ginsenoside Rg3 were consistent with animal experiments. After transfection with Nrf2 short interfering RNA (siRNA), the protective effect of 20(R)-ginsenoside Rg3 on PC12 cells was reversed. In conclusion, the inhibition of mitochondrial oxidative stress plays a vital position in the anti-cerebral ischemia-reperfusion injury of 20(R)-ginsenoside Rg3, and its neuroprotective mechanism is related to the activation of the nuclear factor erythroid2-related factor 2/heme oxygenase 1 signaling pathway.


Assuntos
Isquemia Encefálica , Ginsenosídeos , AVC Isquêmico , Fármacos Neuroprotetores , Traumatismo por Reperfusão , Ratos , Animais , Ratos Sprague-Dawley , Estresse Oxidativo , Fator 2 Relacionado a NF-E2/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fármacos Neuroprotetores/farmacologia , Transdução de Sinais , Traumatismo por Reperfusão/prevenção & controle , Infarto da Artéria Cerebral Média
20.
Exp Neurol ; 374: 114697, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38266765

RESUMO

BACKGROUND: Stroke is one of the leading causes of death and long-term disability worldwide. Previous studies have found that corilagin has antioxidant, anti-inflammatory, anti-atherosclerotic and other pharmacological activities and has a protective effect against cardiac and cerebrovascular injury. OBJECTIVES: The aim of this study was to investigate the protective effects of corilagin against ischemic stroke and to elucidate the underlying molecular mechanisms using network pharmacology, molecular docking, and animal and cell experiments. METHODS: We investigated the potential of corilagin to ameliorate cerebral ischemia-reperfusion injury using in vivo rat middle cerebral artery occlusion/reperfusion (MCAO/R) and in vitro oxygen-glucose deprivation/reoxygenation (OGD/R) models. RESULTS: Our results suggest that corilagin may exert its anti-ischemic stroke effect by interacting with 92 key targets, including apoptosis-associated proteins (Bcl-2, Bax, caspase-3) and PI3K/Akt signaling pathway-related proteins. In vivo and in vitro experiments showed that corilagin treatment improved neurological deficits, attenuated cerebral infarct volume, and mitigated neuronal damage in MCAO/R rats. Corilagin treatment also enhanced the survival of PC12 cells exposed to OGD/R, reduced the rate of LDH leakage, inhibited cell apoptosis, and activated the PI3K/Akt signaling pathway. Importantly, the effects of corilagin on the PI3K/Akt signaling pathway and apoptosis-associated proteins were reversed by the PI3K-specific inhibitor LY294002. CONCLUSIONS: These results indicate that the molecular mechanism of the anti-ischemic effect of corilagin involves inhibiting neuronal apoptosis and activating the PI3K/Akt signaling pathway. These findings provide a theoretical and experimental basis for the further development and application of corilagin as a potential anti-ischemic stroke agent.


Assuntos
Lesões Encefálicas , Isquemia Encefálica , Glucosídeos , Taninos Hidrolisáveis , Fármacos Neuroprotetores , Traumatismo por Reperfusão , Ratos , Animais , Simulação de Acoplamento Molecular , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Farmacologia em Rede , Ratos Sprague-Dawley , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/metabolismo , Traumatismo por Reperfusão/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Lesões Encefálicas/tratamento farmacológico , Apoptose
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