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1.
Front Vet Sci ; 11: 1334026, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38379922

RESUMO

Plant extracts have shown promise as natural feed additives to improve animal health and growth. Ellagic acid (EA), widely present in various plant tissues, offers diverse biological benefits. However, limited research has explored its effects on ruminants. This study aimed to investigate the effects of dietary addition EA on rumen metabolism, apparent digestibility of nutrients, and growth performance in Kazakh sheep. Ten 5-month-old Kazakh sheep with similar body weight (BW), fitted with rumen fistulas, were randomly assigned to two groups: the CON group (basal diet) and the EA group (basal diet + 30 mg/kg BW EA). The experiment lasted 30 days, and individual growth performance was assessed under identical feeding and management conditions. During the experimental period, rumen fluid, fecal, and blood samples were collected for analysis. The results indicated a trend toward increased average daily gain in the EA group compared to the CON group (p = 0.094). Compared with the CON group, the rumen contents of acetic acid and propionic acid were significantly increased in the EA group and reached the highest value at 2 h to 4 h after feeding (p < 0.05). Moreover, the relative abundances of specific rumen microbiota (Ruminococcaceae, uncultured_rumen_bacterium, unclassified_Prevotella, Bacteroidales, Bacteroidota, Bacteroidia, unclassified_Rikenellaceae, and Prevotella_spBP1_145) at the family and genus levels were significantly higher in the EA group (p < 0.05) compared to the CON group. The EA group exhibited significantly higher dry matter intake (p < 0.05) and increased the digestibility of neutral detergent fiber and ether extract when compared with the CON group (p < 0.05). Additionally, the plasma activities of total antioxidant capacity (T-AOC), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) were significantly higher, while malondialdehyde (MDA) concentration was significantly lower in the EA group compared to the CON group (p < 0.05). In conclusion, dietary supplementation with 30 mg/kg BW EA in 5-month-old Kazakh sheep increased the dry matter intakQ16e, apparent digestibility of neutral detergent fiber, and ether extract, as well as the contents of acetic acid and propionic acid in rumen fluid. Moreover, EA supplementation regulated the ruminal microbiota, enhanced antioxidant capacity, and improved daily weight gain.

2.
Int J Mol Sci ; 25(2)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38256188

RESUMO

Nucleotidyl transferases (NTPs) are common transferases in eukaryotes and play a crucial role in nucleotide modifications at the 3' end of RNA. In plants, NTPs can regulate RNA stability by influencing 3' end modifications, which in turn affect plant growth, development, stress responses, and disease resistance. Although the functions of NTP family members have been extensively studied in Arabidopsis, rice, and maize, there is limited knowledge about NTP genes in soybeans. In this study, we identified 16 members of the NTP family in soybeans, including two subfamilies (G1 and G2) with distinct secondary structures, conserved motifs, and domain distributions at the protein level. Evolutionary analysis of genes in the NTP family across multiple species and gene collinearity analysis revealed a relatively conserved evolutionary pattern. Analysis of the tertiary structure of the proteins showed that NTPs have three conserved aspartic acids that bind together to form a possible active site. Tissue-specific expression analysis indicated that some NTP genes exhibit tissue-specific expression, likely due to their specific functions. Stress expression analysis showed significant differences in the expression levels of NTP genes under high salt, drought, and cold stress. Additionally, RNA-seq analysis of soybean plants subjected to salt and drought stress further confirmed the association of soybean NTP genes with abiotic stress responses. Subcellular localization experiments revealed that GmNTP2 and GmNTP14, which likely have similar functions to HESO1 and URT1, are located in the nucleus. These research findings provide a foundation for further investigations into the functions of NTP family genes in soybeans.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Nucleotidiltransferases , Glycine max/genética , Resposta ao Choque Frio , Nucleotídeos , RNA Nucleotidiltransferases
3.
Molecules ; 28(24)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38138470

RESUMO

Walnut green husks (WGHs), by-products of walnut production, are believed to possess antimicrobial properties, making them a potential alternative to antibiotics. In this study, the antibacterial activities of three extracts, derived from WGH, against Staphylococcus aureus, Bacillus subtilis, and Escherichia coli were investigated, and the antibacterial mechanisms of an anhydrous ethanol extract of WGH (WGHa) were examined. The results showed that WGHa exhibited inhibitory effects on all tested bacteria. The ultrahigh-performance liquid chromatography-tandem mass spectrometry analysis revealed that the major active compounds present in WGHa were terpenoids, phenols, and flavonoids. Treatment with WGHa resulted in the leakage of intracellular ions and alkaline phosphatase; a reduction in intracellular ATP content, ATPase activity, and nucleic acid content; as well as cellular metabolic viability. The transmission electron microscopy images showed varying degrees of cell deformation and membrane damage following WGHa treatment. The transcriptome sequencing and differentially expressed gene enrichment analyses revealed an up-regulation in pathways associated with RNA degradation, translation, protein export, and oxidative phosphorylation. Conversely, pathways involved in cell movement and localization, as well as cell wall organization and carbohydrate transport, were found to be down-regulated. These findings suggest that WGHa alters cell membrane permeability and causes damage to the cell wall. Additionally, WGHa interferes with cellular energy metabolism, compromises RNA integrity, and induces DNA replication stress, consequently inhibiting the normal growth and proliferation of bacteria. These findings unveiled the antimicrobial mechanisms of WGHa, highlighting its potential application as an antibiotic alternative.


Assuntos
Anti-Infecciosos , Juglans , Juglans/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Testes de Sensibilidade Microbiana , Antibacterianos/química , Anti-Infecciosos/farmacologia , Bactérias
4.
Environ Sci Pollut Res Int ; 30(13): 35635-35645, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36534259

RESUMO

Heterosigma akashiwo (H. akashiwo), a harmful algal species, has been a global environmental problem. Extracellular algicidal compounds (EACs) extracted from Bacillus sp. B1 exhibited algicidal effects against H. akashiwo. However, little is known about the algicidal mechanism and metabolic process. In this study, metabolomics and physiological analyses were combined to investigate the cellular responses of H. akashiwo when treated with EACs. The results indicated that EACs at 10% (vEACs/vsample) showed more than 90% inhibition of H. akashiwo. EAC treatment resulted in excessive reactive oxygen species (ROS) production in algal cells, causing stress responses such as inhibition of photosynthetic pigment synthesis, reduction of sugar synthesis, imbalance of osmotic pressure in the cell membrane, disruption of cell size and morphology, and eventual cell death. The results reveal the underlying mechanism of the algicidal process and provide new insights into algae-bacteria interactions and the application of metabolomics to algal research.


Assuntos
Bacillus , Dinoflagellida , Estramenópilas , Bactérias , Metabolômica , Fotossíntese , Proliferação Nociva de Algas
5.
Microvasc Res ; 133: 104102, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33166578

RESUMO

This study describes a computational algorithm to determine vascular permeability constants from time-lapse imaging data without concurrent knowledge of the arterial input function. The algorithm is based on "blind" deconvolution of imaging data, which were generated with analytical and finite-element models of bidirectional solute transport between a capillary and its surrounding tissue. Compared to the commonly used Patlak analysis, the blind algorithm is substantially more accurate in the presence of solute delay and dispersion. We also compared the performance of the blind algorithm with that of a simpler one that assumed unidirectional transport from capillary to tissue [as described in Truslow et al., Microvasc. Res. 90, 117-120 (2013)]. The algorithm based on bidirectional transport was more accurate than the one based on unidirectional transport for more permeable vessels and smaller extravascular distribution volumes, and less accurate for less permeable vessels and larger extravascular distribution volumes. Our results indicate that blind deconvolution is superior to Patlak analysis for permeability mapping under clinically relevant conditions, and can thus potentially improve the detection of tissue regions with a compromised vascular barrier.


Assuntos
Algoritmos , Permeabilidade Capilar , Processamento de Imagem Assistida por Computador , Microcirculação , Modelos Cardiovasculares , Imagem com Lapso de Tempo , Animais , Velocidade do Fluxo Sanguíneo , Análise de Elementos Finitos , Humanos , Análise Numérica Assistida por Computador , Fatores de Tempo
6.
J Biomed Mater Res B Appl Biomater ; 108(6): 2441-2449, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32017412

RESUMO

Although much progress has been made in engineering vascular grafts for large- and small-diameter arterial repair or bypass, the extension of these results to the microsurgical size scale has been challenging. Here, we evaluated the use of dense collagen tubes (outer diameter 1 mm, inner diameter 0.5 mm) for vascular microsurgery as interpositional grafts to the femoral artery of Lewis rats. These tubes were formed by dehydrating tubular collagen gels around a mandrel, crosslinking them with genipin, seeding with syngeneic endothelial cells, and culturing before implantation by suture anastomosis. The retention of a confluent endothelial lining inside the tubes after mock surgical handling depended strongly on the crosslinker concentration and culture time. Optimized preparation conditions enabled retention of endothelium after mock surgical handling in ~80% of tubes and maintenance of patency 7 days after implantation in ~40% of grafts. Histological analysis showed the development of granulation tissue and the presence of CD31-positive structures on the inner and outer surfaces of implants. This study provides a proof-of-principle demonstration that endothelialized dense collagen tubes can remain patent for up to 7 days after vascular microsurgery, and points to the importance of mild scaffold crosslinking for maintaining firm endothelial adhesion.


Assuntos
Prótese Vascular , Colágeno/química , Endotélio/química , Microcirurgia/métodos , Procedimentos Cirúrgicos Vasculares/métodos , Animais , Bioprótese , Adesão Celular , Células Cultivadas , Reagentes de Ligações Cruzadas/química , Células Endoteliais , Artéria Femoral/cirurgia , Tecido de Granulação/crescimento & desenvolvimento , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Desenho de Prótese , Ratos , Ratos Endogâmicos Lew , Engenharia Tecidual , Alicerces Teciduais
7.
Biofabrication ; 11(1): 014101, 2018 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-30284537

RESUMO

Current methods to treat large soft-tissue defects mainly rely on autologous transfer of adipocutaneous flaps, a method that is often limited by donor site availability. Engineered vascularized adipose tissues can potentially be a viable and readily accessible substitute to autologous flaps. In this study, we engineered a small-scale adipose tissue with pre-patterned vasculature that enables immediate perfusion. Vessels formed after one day of perfusion and displayed barrier function after three days of perfusion. Under constant perfusion, adipose tissues remained viable and responded to lipoactive hormones insulin and epinephrine with lipid accumulation and loss, respectively. Adipocyte growth correlated inversely with distance away from the feeding vessel, as predicted by a Krogh-type model.


Assuntos
Tecido Adiposo/irrigação sanguínea , Tecido Adiposo/metabolismo , Epinefrina/metabolismo , Insulina/metabolismo , Microvasos/crescimento & desenvolvimento , Engenharia Tecidual/métodos , Adipócitos/citologia , Adipócitos/metabolismo , Tecido Adiposo/crescimento & desenvolvimento , Animais , Proliferação de Células , Hormônios/química , Hormônios/metabolismo , Humanos , Metabolismo dos Lipídeos , Camundongos , Microvasos/metabolismo , Células NIH 3T3 , Perfusão , Engenharia Tecidual/instrumentação
8.
Tissue Eng Part A ; 23(7-8): 335-344, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27998245

RESUMO

Tissue-engineered vascular grafts that are based on reconstituted extracellular matrices have been plagued by weak mechanical strength that prevents handling or anastomosis to native vessels. In this study, we devise a method for making dense, suturable collagen tubular constructs of diameter ≤1 mm for potential microsurgical applications, by dehydrating tubes of native rat tail type I collagen and crosslinking them with 20 mM genipin. Crosslinked dense collagen tubes with 1 mm inner diameter yielded ultimate tensile strength of 342 ± 15 gF and burst pressure of 1313 ± 156 mm Hg, comparable to the strength of a rat femoral artery, and supported endothelial cell adhesion and growth. End-to-end anastomosis of 0.5-mm-diameter tubes to explanted arteries displayed anastomotic strength of 82 ± 21 gF, which is sufficient for surgical applications. In vivo implantation of cell-free tubes as interpositional grafts in the rat femoral circulation yielded stable anastomosis with blood flow for 20 min. Seeded dense collagen tubes represent a promising alternative to venous graft that can potentially be used to bridge between short artery stubs in replantation surgeries.


Assuntos
Prótese Vascular , Colágeno/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Artérias/citologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Ratos , Resistência à Tração
9.
Arterioscler Thromb Vasc Biol ; 35(11): 2354-65, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26338297

RESUMO

OBJECTIVE: Collateral arteriogenesis, the growth of existing arterial vessels to a larger diameter, is a fundamental adaptive response that is often critical for the perfusion and survival of tissues downstream of chronic arterial occlusion(s). Shear stress regulates arteriogenesis; however, the arteriogenic significance of reversed flow direction, occurring in numerous collateral artery segments after femoral artery ligation, is unknown. Our objective was to determine if reversed flow direction in collateral artery segments differentially regulates endothelial cell signaling and arteriogenesis. APPROACH AND RESULTS: Collateral segments experiencing reversed flow direction after femoral artery ligation in C57BL/6 mice exhibit increased pericollateral macrophage recruitment, amplified arteriogenesis (30% diameter and 2.8-fold conductance increases), and remarkably permanent (12 weeks post femoral artery ligation) remodeling. Genome-wide transcriptional analyses on human umbilical vein endothelial cells exposed to reversed flow conditions mimicking those occurring in vivo yielded 10-fold more significantly regulated transcripts, as well as enhanced activation of upstream regulators (nuclear factor κB [NFκB], vascular endothelial growth factor, fibroblast growth factor-2, and transforming growth factor-ß) and arteriogenic canonical pathways (protein kinase A, phosphodiesterase, and mitogen-activated protein kinase). Augmented expression of key proarteriogenic molecules (Kruppel-like factor 2 [KLF2], intercellular adhesion molecule 1, and endothelial nitric oxide synthase) was also verified by quantitative real-time polymerase chain reaction, leading us to test whether intercellular adhesion molecule 1 or endothelial nitric oxide synthase regulate amplified arteriogenesis in flow-reversed collateral segments in vivo. Interestingly, enhanced pericollateral macrophage recruitment and amplified arteriogenesis was attenuated in flow-reversed collateral segments after femoral artery ligation in intercellular adhesion molecule 1(-/-) mice; however, endothelial nitric oxide synthase(-/-) mice showed no such differences. CONCLUSIONS: Reversed flow leads to a broad amplification of proarteriogenic endothelial signaling and a sustained intercellular adhesion molecule 1-dependent augmentation of arteriogenesis. Further investigation of the endothelial mechanotransduction pathways activated by reversed flow may lead to more effective and durable therapeutic options for arterial occlusive diseases.


Assuntos
Artérias/fisiopatologia , Circulação Colateral , Isquemia/fisiopatologia , Mecanotransdução Celular , Músculo Esquelético/irrigação sanguínea , Neovascularização Fisiológica , Animais , Artérias/metabolismo , Artérias/patologia , Velocidade do Fluxo Sanguíneo , Células Cultivadas , Modelos Animais de Doenças , Artéria Femoral/fisiopatologia , Artéria Femoral/cirurgia , Regulação da Expressão Gênica , Membro Posterior , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Isquemia/genética , Isquemia/metabolismo , Isquemia/patologia , Ligadura , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/genética , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Fluxo Sanguíneo Regional , Estresse Mecânico , Fatores de Tempo , Remodelação Vascular
10.
Microcirculation ; 22(5): 360-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25866235

RESUMO

OBJECTIVE: To estimate the relative influence of input pressure and arteriole rarefaction on gastrocnemius muscle perfusion in patients with PAD after exercise and/or percutaneous interventions. METHODS: A computational network model of the gastrocnemius muscle microcirculation was adapted to reflect rarefaction based on arteriolar density measurements from PAD patients, with and without exercise. A normalized input pressure was applied at the feeder artery to simulate both reduced and restored ABI in the PAD condition. RESULTS: In simulations of arteriolar rarefaction, resistance increased non-linearly with rarefaction, leading to a disproportionally large drop in perfusion. In addition, perfusion was less sensitive to changes in input pressure as the degree of rarefaction increased. Reduced arteriolar density was observed in PAD patients and improved 33.8% after three months of exercise. In model simulations of PAD, ABI restoration yielded perfusion recovery to only 66% of baseline. When exercise training was simulated by reducing rarefaction, ABI restoration increased perfusion to 80% of baseline. CONCLUSION: Microvascular resistance increases non-linearly with increasing arteriole rarefaction. Therefore, muscle perfusion becomes disproportionally less sensitive to ABI restoration as arteriole rarefaction increases. These results highlight the importance of restoring both microvascular structure and upstream input pressure in PAD therapy.


Assuntos
Simulação por Computador , Hemodinâmica , Modelos Cardiovasculares , Músculo Esquelético/irrigação sanguínea , Doença Arterial Periférica/fisiopatologia , Animais , Arteríolas/fisiopatologia , Humanos
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