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1.
Int J Mol Sci ; 25(6)2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38542373

RESUMO

The glycoside hydrolase 13 (GH13) family is crucial for catalyzing α-glucoside linkages, and plays a key role in plant growth, development, and stress responses. Despite its significance, its role in plants remains understudied. This study targeted four GH13 subgroups in wheat, identifying 66 GH13 members from the latest wheat database (IWGSC RefSeq v2.1), including 36 α-amylase (AMY) members, 18 1,4-α-glucan-branching enzyme (SBE) members, 9 isoamylase (ISA) members, and 3 pullulanase (PU) members. Chromosomal distribution reveals a concentration of wheat group 7 chromosomes. Phylogenetic analysis underscores significant evolutionary distance variations among the subgroups, with distinct molecular structures. Replication events shaped subgroup evolution, particularly in regard to AMY members. Subcellular localization indicates AMY member predominance in extracellular and chloroplast regions, while others localize solely in chloroplasts, confirmed by the heterologous expression of TaSEB16 and TaAMY1 in tobacco. Moreover, 3D structural analysis shows the consistency of GH13 across species. Promoter cis-acting elements are suggested to be involved in growth, stress tolerance, and starch metabolism signaling. The RNA-seq data revealed TaGH13 expression changes under drought and submergence stress, and significant expression variation was observed between strong and weak gluten varieties during seed germination using quantitative real-time PCR (qRT-PCR), correlating with seed starch content. These findings demonstrate the pivotal role of GH13 family gene expression in wheat germination, concerning variety preference and environmental stress. Overall, this study advances the understanding of wheat GH13 subgroups, laying the groundwork for further functional studies.


Assuntos
Genoma de Planta , Triticum , Triticum/metabolismo , Filogenia , Glicosídeo Hidrolases/metabolismo , Amido/metabolismo , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas , Família Multigênica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
2.
Int J Mol Sci ; 24(4)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36834758

RESUMO

Radiation is widespread in nature, including ultraviolet radiation from the sun, cosmic radiation and radiation emitted by natural radionuclides. Over the years, the increasing industrialization of human beings has brought about more radiation, such as enhanced UV-B radiation due to ground ozone decay, and the emission and contamination of nuclear waste due to the increasing nuclear power plants and radioactive material industry. With additional radiation reaching plants, both negative effects including damage to cell membranes, reduction of photosynthetic rate and premature aging and benefits such as growth promotion and stress resistance enhancement have been observed. ROS (Reactive oxygen species) are reactive oxidants in plant cells, including hydrogen peroxide (H2O2), superoxide anions (O2•-) and hydroxide anion radicals (·OH), which may stimulate the antioxidant system of plants and act as signaling molecules to regulate downstream reactions. A number of studies have observed the change of ROS in plant cells under radiation, and new technology such as RNA-seq has molecularly revealed the regulation of radiative biological effects by ROS. This review summarized recent progress on the role of ROS in plant response to radiations including UV, ion beam and plasma, and may help to reveal the mechanisms of plant responses to radiation.


Assuntos
Peróxido de Hidrogênio , Raios Ultravioleta , Humanos , Espécies Reativas de Oxigênio/metabolismo , Superóxidos , Antioxidantes/metabolismo
3.
Cell Biochem Funct ; 38(7): 886-894, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32196715

RESUMO

According to statistics, abnormal regulation of lncRNAs pivotally influences multiple malignant tumours. DLEU2, as one of these lncRNAs, is detected to be related to growth and development of tumours. The molecular mechanisms of DLEU2 in osteosarcoma, however, are still unknown. QRT-PCR was adopted to analyse the correlations of clinicopathological features and prognosis of osteosarcoma cases with DLEU2. The influences of DLEU2 on cell migration and viability were evaluated independently by experiments in vitro and in vivo. Bioinformatics analysis, RNA immunoprecipitation (RIP) assay, and dual luciferase reporter gene assay confirmed the specific binding of DLEU2 to miR-337-3p. Moreover, rescue experiments were carried out to further evaluate the regulatory association between miR-337-3p expression and DLEU2. In osteosarcoma tissues and cells, DLEU2 expression level was raised remarkably in comparison with that in para-carcinoma normal tissues, and DLEU2 high expression had associations with poor prognosis, tumour stages, and TS of osteosarcoma cases. Cell migration ability and viability were blocked by DLEU2 knockdown but enhanced by ectopic DLEU2 expression in vitro and in vivo. Additionally, DLEU2 was found to sponge miR-337-3p and trigger the stimulating effect in osteosarcoma cells, which would be suppressed by miR-337-3p mimics. Furthermore, a negative correlation existed between miR-337-3p expression and DLEU2 in osteosarcoma tissues. This study manifests that DLEU2 sponges miR-337-3p to accelerate tumour growth and is confirmed to be a factor for poor prognosis of osteosarcoma cases. SIGNIFICANCE OF THE STUDY: LncRNA DLEU2 has been reported to be dysregulated in many tumours; however, the functions and underlying mechanism of DLEU2 in osteosarcoma pathogenesis are still unknown. This study is the first to demonstrate the roles of DLEU2 in osteosarcoma and revealed that DLEU2 may serve as a ceRNA to sponge miR-337-3p and then promote the progression of osteosarcoma, providing a potential therapeutic target for osteosarcoma.


Assuntos
Proliferação de Células , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Antagomirs/metabolismo , Área Sob a Curva , Sequência de Bases , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Movimento Celular , Humanos , Camundongos , Camundongos Nus , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Osteossarcoma/tratamento farmacológico , Osteossarcoma/genética , Osteossarcoma/patologia , Interferência de RNA , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/genética , RNA Interferente Pequeno/metabolismo , RNA Interferente Pequeno/uso terapêutico , Curva ROC , Alinhamento de Sequência , Transplante Heterólogo
4.
Funct Integr Genomics ; 19(6): 853-866, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31115762

RESUMO

Wheat grain development is a robust biological process that largely determines grain quality and yield. In this study, we investigated the grain transcriptome of winter wheat cv. Xiaoyan-6 at four developmental stages (5, 10, 15, and 20 days post-anthesis), using high-throughput RNA sequencing (RNA-Seq). We identified 427 grain-specific transcription factors (TFs) and 1653 differentially expressed TFs during grain development as well as a grain co-expression regulation network (GrainNet) of the TFs and their predicted co-expressed genes. Our study identified ten putative key TFs and the predicted regulatory genes of these TFs in wheat grain development of Xiaoyan-6. The analysis was given a firm basis through the study of additional wheat tissues, including root, stem, leaf, flag leaf, grain, spikes (from wheat plants at booting or heading stages) to provide a dataset of 92,478 high-confidence protein-coding genes that were mostly evenly distributed among subgenomes, but unevenly distributed across each of the chromosomes or each of the seven homeologous groups. Within this larger framework of the transcriptomes, we identified 4659 grain-specific genes (SEGs) and 26,500 differentially expressed genes (DEGs) throughout grain development stages tested. The SEGs identified mainly associate with regulation and signaling-related biological processes, while the DEGs mainly involve in cellular component organization or biogenesis and nutrient reservoir activity during grain development of Xiaoyan-6. This study establishes new targets for modifying genes related to grain development and yield, to fine-tune expression in different varieties and environments.


Assuntos
Grão Comestível/genética , Redes Reguladoras de Genes , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Transcriptoma , Triticum/genética , Grão Comestível/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Triticum/crescimento & desenvolvimento
5.
J Therm Biol ; 81: 137-145, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30975411

RESUMO

Brown adipose tissue (BAT) plays an important role in thermoregulation and many metabolic processes in small mammals, especially in cold adaptation. However, in warm adaptation, ambient temperature cannot directly activate BAT by sympathetic nervous system. Mongolian gerbils exhibit a wider thermoneutral zone (26.5-38.9 °C). We hypothesized that BAT atrophied near the lower critical temperature and further atrophied near the upper critical temperature. Male gerbils were acclimated to 23 °C, 27 °C or 37 °C, respectively, for 3 weeks. Results showed that regulatory non-shivering thermogenesis did not change in gerbils acclimated to 27 °C compared with 23 °C group, whereas it was reduced by 43.5% in gerbils acclimated to 37 °C. Bigger lipid droplet in BAT was observed in gerbils acclimated to 27 °C and 37 °C compared with 23 °C group, while the expression of uncoupling protein 1 and tyrosine hydroxylase was only reduced in gerbils acclimated to 37 °C. Further, thermoneutral acclimation did not change BAT thermogenesis by down-regulation of peroxisome proliferator-activated receptor gamma coactivator-1α, PR domain containing 16, peroxisome proliferator-activated receptor-α or peroxisome proliferator activated receptor-γ gene expression in BAT. In addition, body temperature was reduced in gerbils acclimated to 37 °C compared with 23 °C group, which was associated with a decreased resting metabolic rate and regulatory non-shivering thermogenesis. In conclusion, BAT does not atrophy near the lower critical temperature, whereas it atrophies near the upper critical temperature, suggesting that BAT may play thermoregulatory role within the TNZ in Mongolian gerbils.


Assuntos
Tecido Adiposo Marrom/fisiologia , Regulação da Temperatura Corporal , Gerbillinae/fisiologia , Termotolerância , Tecido Adiposo Marrom/citologia , Animais , Metabolismo Basal , Ingestão de Alimentos , Gerbillinae/metabolismo , Masculino , Tamanho do Órgão , Temperatura , Termogênese , Tirosina 3-Mono-Oxigenase/metabolismo , Proteína Desacopladora 1/metabolismo
6.
Horm Behav ; 98: 55-62, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29288636

RESUMO

Aggression can benefit individuals by enhancing their dominance and thereby their ability to acquire and retain resources that increase survival or fitness. Engaging in aggressive behavior costs energy and how animals manage their energy budget to accommodate aggression remains unclear. We conducted three experiments to examine changes in physiological, behavioral and hormonal markers indicative of energy budget in male striped hamsters subject to resident-intruder aggression tests. Body temperature, metabolic rate and serum corticosterone levels significantly increased in resident hamsters immediately after the introduction of intruders. Energy intake did not change, but the metabolic rate of residents increased by 16.1% after 42-days of repeated encounters with intruders. Residents had significantly decreased body fat content and serum thyroxine (T4) levels, and a considerably elevated tri-iodothyronine (T3)/T4 ratio compared to a control group that had no intruders. Attack latency considerably shortened, and the number of attack bouts and total duration of attacks, significantly increased in residents on day 42 compared to day 1 of experiments. These findings may suggest that the conversion of T4 to T3 is involved in defensive aggression behavior. The mobilization of fat reserves resulting in lean body mass is probably common response to the increased metabolic cost of aggression in small mammals. Aggressive behavior, which is important for the successful acquisition and defense of resources, may be of significance for adaptation and evolution of metabolic rate.


Assuntos
Tecido Adiposo/metabolismo , Agressão/fisiologia , Metabolismo Energético/fisiologia , Lipólise/fisiologia , Animais , Comportamento Animal/fisiologia , Temperatura Corporal/fisiologia , Corticosterona/sangue , Cricetinae , Ingestão de Energia/fisiologia , Mobilização Lipídica/fisiologia , Masculino , Consumo de Oxigênio/fisiologia , Tiroxina/sangue , Tri-Iodotironina/sangue
7.
J Therm Biol ; 71: 189-194, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29301689

RESUMO

The initiation of torpor is supposed to be related to the availability of metabolic fuels. Studies on metabolic fuel inhibition of glucose by using 2-deoxy-D-glucose (2DG) or fatty acid by mercaptoacetate (MA) in heterothermic mammals produced mixed outcomes. To examine the roles of availability of glucose and fatty acid in the initiation of torpor in desert hamsters (Phodopus roborovskii), we intraperitoneally administrated 2DG and MA to summer-acclimated male hamsters while body temperature (Tb), metabolic rate (MR) and respiratory quotient (RQ) were simultaneously recorded to monitor their thermoregulatory response. 2DG induced a reversible reduction of Tb in desert hamsters both at ambient temperature (Ta) of 23°C and 5°C. At Ta of 23°C, Tb, MR and RQ decreased in a dose-dependent manner with a large Tb-Ta differential (> 6.5°C) and a lowest Tb of 28.0°C which were comparable to those in fasted hamsters. At Ta of 5°C, 2DG-treated hamsters also decreased Tb to the same level as at Ta 23°C, but MR was significantly higher than that at Ta of 23°C at each dose, suggesting doses of 2DG directly affected the hypothalamic Tb set-point. Different from fasted hamsters which maintain normothermic at Ta of 5°C, 2DG-treated hamsters showed a substantial reduction of Tb at Ta 5°C, indicating an overwhelming effect on the thermoregulatory system regardless of Ta. Furthermore, the rapid decrease of Tb and outstretched body posture in 2DG-treated hamsters suggest that the effects of 2DG were not simply mimicking the torpor pathways but that other mechanisms are involved. Interestingly, MA failed to induce a torpor-like state in male desert hamsters. Our results suggest that availability of glucose rather than fatty acid plays an important role for initiation of torpor in desert hamsters.


Assuntos
Antimetabólitos/farmacologia , Temperatura Corporal/efeitos dos fármacos , Desoxiglucose/farmacologia , Phodopus/fisiologia , Tioglicolatos/farmacologia , Animais , Metabolismo Basal , Cricetinae , Hipotálamo/fisiologia , Masculino , Respiração , Torpor/efeitos dos fármacos
8.
J Therm Biol ; 74: 241-248, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29801634

RESUMO

Sympatric species can coexist through ecological resource partitioning as for example for habitat, food or time. However, a detailed understanding of the basic thermal physiology, crucial for temporal partitioning, is currently lacking, especially for the desert rodents. Here, we compare the physiological performance with regard to thermal energetics and morphological traits of two sympatric gerbils from the Gobi desert of Inner Mongolia, China. The diurnally active Meriones unguiculatus and the nocturnally active M. meridianus. The diurnal M. unguiculatus had more brown adipose tissue (BAT) mass and capacity for non-shivering thermogenesis (NST), a higher resting metabolic rate (RMR) at low ambient temperatures (Ta) and a higher upper critical temperature of the thermal neutral zone (TNZ) than the nocturnal M. meridianus. The overall thermal conductance and lower critical temperatures of M. unguiculatus were also higher than that of M. meridianus, permitting the former to maintain a stable body temperature (Tb) when exposed to high Ta. Laboratory-bred M. meridianus also showed higher daily water intake. We found no differences in body mass, and total evaporative water loss (TEWL) between the two species captured from the natural environment. These results suggest that the diurnal M. unguiculatus have a higher tolerance of high Tas, whereas M. meridianus can save more energy at low Tas. Therefore, from the view point of energy conservation, our results suggest that the nocturnal ecophenotype in M. meridianus is constrained by a lower ability for heat resistance, but this is not the case for the diurnal M. unguiculatus.


Assuntos
Comportamento Animal , Regulação da Temperatura Corporal , Gerbillinae/fisiologia , Animais , Ingestão de Alimentos , Feminino , Gerbillinae/metabolismo , Masculino , Especificidade da Espécie , Simpatria , Termogênese
9.
Artigo em Inglês | MEDLINE | ID: mdl-28711354

RESUMO

The metabolic thermogenesis plays important roles in thermoregulation, and it may be also involved in body fat regulation. The thermogenesis of brown adipose tissue (BAT) is largely affected by ambient temperature, but it is unclear if the roles in body fat regulation are dependent on the temperature. In the present study, uncoupling protein 1 (ucp1)-based BAT thermogenesis, energy budget and body fat content were examined in the striped hamsters fed high fat diet (HF) at cold (5°C) and warm (30°C) temperatures. The effect of 2, 4-dinitrophenol (DNP), a chemical uncoupler, on body fat was also examined. The striped hamsters showed a notable increase in body fat following the HF feeding at 21°C. The increased body fat was markedly elevated at 30°C, but was significantly attenuated at 5°C compared to that at 21°C. The hamsters significantly increased energy intake at 5°C, but consumed less food at 30°C relative to those at 21°C. Metabolic thermogenesis, indicated by basal metabolic rate, UCP1 expression and/or serum triiodothyronine levels, significantly increased at 5°C, but decreased at 30°C compared to that at 21°C. A significant decrease in body fat content was observed in DNP-treated hamsters relative to the controls. These findings suggest that the roles of metabolic thermogenesis in body fat regulation largely depend on ambient temperature. The cold-induced enhancement of BAT thermogenesis may contribute the decreased body fat, resulting in a lean mass. Instead, the attenuation of BAT thermogenesis at the warm may result in notable obesity.


Assuntos
Tecido Adiposo/metabolismo , Dieta Hiperlipídica , Termogênese , Animais , Metabolismo Basal , Cricetinae , Temperatura
10.
Artigo em Inglês | MEDLINE | ID: mdl-27215346

RESUMO

Daily torpor is frequently expressed in small rodents when facing energetically unfavorable ambient conditions. Desert hamsters (Phodopus roborovskii, ~20g) appear to be an exception as they have been described as homeothermic. However, we hypothesized that they can use torpor because we observed reversible decreases of body temperature (Tb) in fasted hamsters. To test this hypothesis we (i) randomly exposed fasted summer-acclimated hamsters to ambient temperatures (Tas) ranging from 5 to 30°C or (ii) supplied them with different rations of food at Ta 23°C. All desert hamsters showed heterothermy with the lowest mean Tb of 31.4±1.9°C (minimum, 29.0°C) and 31.8±2.0°C (minimum, 29.0°C) when fasted at Ta of 23°C and 19°C, respectively. Below Ta 19°C, the lowest Tb and metabolic rate increased and the proportion of hamsters using heterothermy declined. At Ta 5°C, nearly all hamsters remained normothermic by increasing heat production, suggesting that the heterothermy only occurs in moderately cold conditions, perhaps to avoid freezing at extremely low Tas. During heterothermy, Tbs below 31°C with metabolic rates below 25% of those during normothermia were detected in four individuals at Ta of 19°C and 23°C. Consequently, by definition, our observations confirm that fasted desert hamsters are capable of shallow daily torpor. The negative correlation between the lowest Tbs and amount of food supply shows that heterothermy was mainly triggered by food shortage. Our data indicate that summer-acclimated desert hamsters can express fasting-induced shallow daily torpor, which may be of significance for energy conservation and survival in the wild.


Assuntos
Regulação da Temperatura Corporal/fisiologia , Jejum/fisiologia , Phodopus/fisiologia , Torpor/fisiologia , Aclimatação/fisiologia , Animais , Metabolismo Basal/fisiologia , Tamanho Corporal/fisiologia , Temperatura Corporal/fisiologia , Cricetinae , Feminino , Masculino , Consumo de Oxigênio/fisiologia , Estações do Ano , Temperatura , Termogênese/fisiologia
11.
BMC Genomics ; 15: 289, 2014 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-24734873

RESUMO

BACKGROUND: MicroRNAs (miRNAs) regulate various biological processes in plants. Considerable data are available on miRNAs involved in the development of rice, maize and barley. In contrast, little is known about miRNAs and their functions in the development of wheat. In this study, five small RNA (sRNA) libraries from wheat seedlings, flag leaves, and developing seeds were developed and sequenced to identify miRNAs and understand their functions in wheat development. RESULTS: Twenty-four known miRNAs belonging to 15 miRNA families were identified from 18 MIRNA loci in wheat in the present study, including 15 miRNAs (9 MIRNA loci) first identified in wheat, 13 miRNA families (16 MIRNA loci) being highly conserved and 2 (2 MIRNA loci) moderately conserved. In addition, fifty-five novel miRNAs were also identified. The potential target genes for 15 known miRNAs and 37 novel miRNAs were predicted using strict criteria, and these target genes are involved in a wide range of biological functions. Four of the 15 known miRNA families and 22 of the 55 novel miRNAs were preferentially expressed in the developing seeds with logarithm (log2) of the fold change of 1.0 ~ 7.6, and half of them were seed-specific, suggesting that they participate in regulating wheat seed development and metabolism. From 5 days post-anthesis to 20 days post-anthesis, miR164 and miR160 increased in abundance in the developing seeds, whereas miR169 decreased, suggesting their coordinating functions in the different developmental stages of wheat seed. Moreover, 8 known miRNA families and 28 novel miRNAs exhibited tissue-biased expression in wheat flag leaves, with the logarithm of the fold changes of 0.1 ~ 5.2. The putative targets of these tissue-preferential miRNAs were involved in various metabolism and biological processes, suggesting complexity of the regulatory networks in different tissues. Our data also suggested that wheat flag leaves have more complicated regulatory networks of miRNAs than developing seeds. CONCLUSIONS: Our work identified and characterised wheat miRNAs, their targets and expression patterns. This study is the first to elucidate the regulatory networks of miRNAs involved in wheat flag leaves and developing seeds, and provided a foundation for future studies on specific functions of these miRNAs.


Assuntos
MicroRNAs/genética , Folhas de Planta/genética , Sementes/genética , Triticum/genética , Análise por Conglomerados , Biologia Computacional/métodos , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Sequenciamento de Nucleotídeos em Larga Escala , MicroRNAs/química , Especificidade de Órgãos/genética , Precursores de RNA/genética , RNA Mensageiro/genética , Reprodutibilidade dos Testes
12.
J Exp Biol ; 216(Pt 17): 3358-68, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23737554

RESUMO

We evaluated factors limiting lactating Mongolian gerbils (Meriones unguiculatus) at three temperatures (10, 21 and 30°C). Energy intake and daily energy expenditure (DEE) increased with decreased ambient temperature. At peak lactation (day 14 of lactation), energy intake increased from 148.7±5.7 kJ day(-1) at 30°C to 213.1±8.2 kJ day(-1) at 21°C and 248.7±12.3 kJ day(-1) at 10°C. DEE increased from 105.1±4.0 kJ day(-1) at 30°C to 134.7±5.6 kJ day(-1) at 21°C and 179.5±8.4 kJ day(-1) at 10°C on days 14-16 of lactation. With nearly identical mean litter sizes, lactating gerbils at 30°C exported 32.0 kJ day(-1) less energy as milk at peak lactation than those allocated to 10 or 21°C, with no difference between the latter groups. On day 14 of lactation, the litter masses at 10 and 30°C were 12.2 and 9.3 g lower than those at 21°C, respectively. Lactating gerbils had higher thermal conductance of the fur and lower UCP-1 levels in brown adipose tissue than non-reproductive gerbils, independent of ambient temperature, suggesting that they were attempting to avoid heat stress. Thermal conductance of the fur was positively related to circulating prolactin levels. We implanted non-reproductive gerbils with mini-osmotic pumps that delivered either prolactin or saline. Prolactin did not influence thermal conductance of the fur, but did reduce physical activity and UCP-1 levels in brown adipose tissue. Transferring lactating gerbils from warm to hot conditions resulted in reduced milk production, consistent with the heat dissipation limit theory, but transferring them from warm to cold conditions did not elevate milk production, consistent with the peripheral limitation hypothesis, and placed constraints on pup growth.


Assuntos
Regulação da Temperatura Corporal , Ingestão de Alimentos , Ingestão de Energia , Gerbillinae/fisiologia , Lactação , Animais , Feminino , Temperatura
13.
Zhen Ci Yan Jiu ; 48(6): 541-9, 2023 Jun 25.
Artigo em Zh | MEDLINE | ID: mdl-37385784

RESUMO

OBJECTIVE: To observe the effect of "Tiaoshen Tongluo" acupuncture (TTA) at "Dingzhongxian" (MS5) and right "Dingpangxian" (MS8) on neurological injury, muscle tension and neurotransmitters through nuclear transcription factor E2 related factor 2 (Nrf2)/reactive oxygen species (ROS) signaling pathway in spastic rats after stroke, so as to explore its mechanisms underlying relief of post-stroke spasm (PSS). METHODS: A total of 90 male SD rats were randomly divided into 6 groups, i.e. sham operation, PSS model, medication, non-acupoint acupuncture, TTA, TTA+ML385 groups, with 15 rats in each group. The PSS model was established by middle cerebral artery occlusion. After modeling, rats of the medication group were treated by gavage of baclofen (0.4 mg/kg), once daily for 7 days. For rats of the non-acupoint acupuncture group, the spot about 10 mm above the iliac crest and below the armpit of the affected side was needled, and for those of the TTA group and TTA+ML385 group, EA stimulation (1 mA, 2 Hz/15 Hz) was applied to MS5 and right MS8 for 10 min, once daily for 7 consecutive days. Intraperitoneal injection of ML385 [ a specific nuclear factor erythroid 2-related factor 2 (Nrf2) inhibitor, 30 mg/kg] was given to rats of the TTA+ML385 group before TTA was performed. The rats' neurological deficit score (0-4 points) was evaluated by referring to Zea Longa's methods and the muscular spasm degree of the quadriceps femoris of the left hindlimb (0-4 points) assessed by using Ashworth scale (MAS). The muscular tension of the left quadriceps femoris was measured by using a tension sensor, and Hoffman (H)-reflex response and M and H waves of electromyogram of the muscle between the metatarsals of the left foot were measured using an electrophysiological recorder. The cerebral infarction volume was measured after 2,3,5-triphenyltetrazolium chloride (TTC) staining. The contents of γ-aminobutyric acid (GABA), glycine (Gly), glutamic acid (Glu) and aspartic acid (Asp) of the right cortical infarct area were detected by using high performance capillary electrophoresis, and the contents of 5-hydroxytryptamine (5-HT), dopamine (DA) and norepinephrine (NE) were detected by fluorescence spectrophoto-metry, as well as the level of ROS in the right cerebral cortical infarction tissues was detected by dihydroethidium staining. The expression levels of Nrf2 and heme oxygenase-1 (HO-1) proteins in the infarcted cerebral area were detected using Western blot. RESULTS: Compared with the sham operation group, the neurological deficit score, MAS score, percentage of cerebral infarction volume, Hmax/Mmax ratio, contents of Glu and Asp and ROS level were significantly increased (P<0.001), whereas the muscle tone, stimulation threshold for inducing H-reflex, GABA, Gly, 5-HT, DA and NE contents, cerebral Nrf2 and HO-1 protein expression levels were apparently decreased (P<0.001) in the model group. In comparison with the model group, the neurological deficit score, MAS score, percentage of cerebral infarction volume, Hmax/Mmax ratio, contents of Glu, Asp and ROS levels were decreased (P<0.001), and the muscle tone, stimulation threshold for inducing H-reflex, GABA, Gly, 5-HT, DA and NE contents, Nrf2 and HO-1 protein expressions were increased (P<0.001, P<0.01) in both the medication and TTA groups. No significant differences were found between the non-acupoint group and model group, and between the medication and TTA groups in all the indexes mentioned above (P>0.05). After administration of ML385, the effects of TTA in reducing neurological deficit score, MAS score, Hmax/Mmax, percentage of cerebral infarct volume, Glu, Asp, ROS, and up-regulating H-reflex threshold, GABA, Gly, 5-HT, DA, NE, Nrf2 and HO-1 levels were eliminated (P<0.001,P<0.05,P<0.01). CONCLUSION: TTA can improve neurological behavior and muscle spasm in rats with PSS, which may be associated with its functions in regulating the levels of neurotransmitters in the cortical infarcted area by activating the Nrf2/ROS signaling pathway.


Assuntos
Terapia por Acupuntura , Acidente Vascular Cerebral , Masculino , Animais , Ratos , Ratos Sprague-Dawley , Tono Muscular , Espasticidade Muscular/tratamento farmacológico , Fator 2 Relacionado a NF-E2/genética , Espécies Reativas de Oxigênio , Serotonina , Acidente Vascular Cerebral/terapia , Anticorpos , Ácido Aspártico , Neurotransmissores , Infarto Cerebral
14.
Front Plant Sci ; 14: 1337640, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38312361

RESUMO

Introduction: Heavy ion beam is a novel approach for crop mutagenesis with the advantage of high energy transfer line density and low repair effect after injury, however, little investigation on the biological effect on plant was performed. 50 Gy irradiation significantly stimulated the growth of Arabidopsis seedlings, as indicated by an increase in root and biomass, while 200 Gy irradiation significantly inhibited the growth of seedlings, causing a visible decrease in plant growth. Methods: The Arabidopsis seeds were irradiated by 12C6+. Monte Carlo simulations were used to calculate the damage to seeds and particle trajectories by ion implantation. The seed epidermis received SEM detection and changes in its organic composition were detected using FTIR. Evidence of ROS and antioxidant systems were analyzed. RNA-seq and qPCR were used to detect changes in seedling transcript levels. Results and discussion: Monte Carlo simulations revealed that high-dose irradiation causes various damage. Evidence of ROS and antioxidant systems implies that the emergence of phenotypes in plant cells may be associated with oxidative stress. Transcriptomic analysis of the seedlings demonstrated that 170 DEGs were present in the 50 Gy and 200 Gy groups and GO enrichment indicated that they were mainly associated with stress resistance and cell wall homeostasis. Further GO enrichment of DEGs unique to 50 Gy and 200 Gy revealed 58 50Gy-exclusive DEGs were enriched in response to oxidative stress and jasmonic acid entries, while 435 200 Gy-exclusive DEGs were enriched in relation to oxidative stress, organic cyclic compounds, and salicylic acid. This investigation advances our insight into the biological effects of heavy ion irradiation and the underlying mechanisms.

15.
J Funct Biomater ; 13(4)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36547550

RESUMO

BACKGROUND: The mortality of acute aortic dissection (AD) can reach 65~70%. However, it is challenging to follow the progress of AD formation. The purpose of this work was to observe the process of dissection development using a novel tear-embedded silicone phantom. METHODS: Silicone phantoms were fabricated by embedding a torn area and primary tear feature on the inner layer. CT scanning and laser lightening were conducted to observe the variations in thickness and volume of the true lumen (TL) and false lumen (FL) during development. RESULTS: The model with a larger interlayer adhesion damage required a lower pressure to trigger the development of dissection. At the initiation stage of dissection, the volume of TL increased by 25.5%, accompanied by a 19.5% enlargement of tear size. The force analysis based on the change of tear size verified the deduction of the process of interlaminar separation from the earlier studies. CONCLUSIONS: The primary tear and the weakening adhesion of the vessel layers are key factors in AD development, suggesting that some forms of primary damage to the arterial wall, in particular, the lumen morphology of vessels with straight inner lumen, should be considered as early risk predictors of AD.

16.
Cardiovasc Eng Technol ; 12(2): 200-214, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33263929

RESUMO

PURPOSE: In vitro patient-specific flexible vascular models are helpful for understanding the haemodynamic changes before and after endovascular treatment and for effective training of neuroendovascular interventionalists. However, it is difficult to fabricate models of overall unified or controllable thickness using existing manufacturing methods. In this study, we developed an improved and easily implemented method by combining 3D printing and brush-spin-coating processes to produce a transparent silicone model of uniform or varied thickness. METHODS: First, a water-soluble inner-skeleton model, based on clinical data, was printed on a 3D printer. The skeleton model was subsequently fixed in a single-axis-rotation machine to enable continuous coating of silicone, the thickness of which was manually controlled by adsorption and removal of excess silicone in a brush-spinning operation. After the silicone layer was solidified, the inner skeleton was further dissolved in a hot water bath, affording a transparent vascular model with real geometry. To verify the controllability of the coating thickness by using this method, a straight tube, an idealised aneurysm model, a patient-specific aortic arch model, and an abdominal aortic aneurysm model were manufactured. RESULTS: The different thicknesses of the manufactured tubes could be well controlled, with the relative standard deviations being 5.6 and 8.1% for the straight and aneurysm tubes, respectively. Despite of the diameter changing from 33 to 20 mm in the patient-specific aorta, the thickness of the fabricated aortic model remains almost the same along the longitudinal direction with a lower standard deviation of 3.1%. In the more complex patient-specific abdominal aneurysm model, varied thicknesses were realized to mimic the measured data from the CT images, where the middle of the aneurysm was with 2 mm and abdominal aorta as well as the iliac arteries had the normal thickness of 2.3 mm. CONCLUSION: Through the brush-spin-coating method, models of different sizes and complexity with prescribed thickness can be manufactured, which will be helpful for developing surgical treatment strategies or training neuroendovascular interventionalists.


Assuntos
Aneurisma da Aorta Abdominal , Modelos Anatômicos , Aorta , Aorta Torácica , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/cirurgia , Humanos , Impressão Tridimensional
17.
Mol Immunol ; 133: 1-13, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33610121

RESUMO

Transcription factor PU.1 is a regulator of macrophage function, however, the specific function of PU.1 in teleost monocytes/macrophages (MO/MФ) remains unknown. We determined the cDNA sequence of two PU.1 genes from ayu (Plecoglossus altivelis; PaPU.1a and PaPU.1b). Sequence comparisons showed that PaPU.1 were most closely related to the PU.1 of rainbow smelt (Osmerus mordax). The PU.1 transcripts were mainly expressed in the spleen, and their expression was altered in various tissues upon infection with Vibrio anguillarum. PaPU.1a and PaPU.1b proteins were upregulated in MO/MФ, after infection. RNA interference was employed to knockdown PaPU.1a and PaPU.1b to investigate their function in MO/MФ. The expression of inflammatory cytokines was regulated by PaPU.1a, but not PaPU.1b, in ayu MO/MФ upon V. anguillarum infection. Both PaPU.1a and PaPU.1b knockdown lowered the phagocytic activity of MO/MФ. Furthermore, PaPU.1b knockdown attenuated MO/MФ bacterial killing capability. Our results indicate that two PaPU.1 genes differentially modulate the immune response in ayu MO/MФ against bacterial infection.


Assuntos
Macrófagos/imunologia , Monócitos/imunologia , Osmeriformes/genética , Osmeriformes/imunologia , Proteínas Proto-Oncogênicas/genética , Transativadores/genética , Sequência de Aminoácidos , Animais , Sequência de Bases/genética , Citocinas/imunologia , Doenças dos Peixes/imunologia , Proteínas de Peixes/genética , Imunidade Inata/genética , Imunidade Inata/imunologia , Masculino , Fagocitose/genética , Fagocitose/imunologia , Isoformas de Proteínas/genética , Proteínas Proto-Oncogênicas/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Transativadores/metabolismo , Vibrio/imunologia , Vibrioses/imunologia
18.
J Exp Biol ; 213(Pt 23): 3988-97, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21075940

RESUMO

The limitation on sustainable energy intake (SusEI) is important because it establishes the upper energetic limit on the ability of animals to disperse, survive and reproduce. However, there are still arguments about what factors impose that limitation. Thermoregulation in cold environments imposes great energy demands on small mammals. A cold-exposed animal has been suggested to be a model suitable for testing these factors. Here, we examined the changes in food intake and digestible energy intake (DEI) as measures of SusEI, thermogenic capacity and behavioral patterns in Swiss mice exposed to consecutively lower ambient temperatures from 23 to -15°C. Cold-exposed mice showed significant decreases in body mass, fat content of the carcass and body temperature, and increases in DEI compared with controls. The time spent on feeding significantly increased with decreasing temperatures, and time spent on general activity decreased following cold exposure. Resting metabolic rate, nonshivering thermogenesis and serum tri-iodothyronine levels significantly increased in mice exposed to lower temperatures in comparison with controls, whereas these thermogenic variables were not significantly different between 0 and -15°C. It might suggest that SusEI in cold exposed Swiss mice was constrained peripherally by the capacity to produce heat and also by the ability to dissipate body heat, but to a different extent. Moderate cold exposure might result in a relaxation of the heat dissipation limit (HDL), allowing the animals to increase food intake to meet cold stress. When animals are exposed to severe cold, the thermogenenic capacity might reach a ceiling, failing to compensate for the heat loss and which would finally result in lower body temperature and considerable weight loss. This might indicate that the HDL was set at a higher level than peripheral limits for Swiss mice exposed to a consecutive decrease in ambient temperatures.


Assuntos
Comportamento Animal/fisiologia , Temperatura Baixa , Metabolismo Energético/fisiologia , Termogênese/fisiologia , Adiposidade/fisiologia , Animais , Metabolismo Basal/fisiologia , Composição Corporal/fisiologia , Peso Corporal/fisiologia , Digestão/fisiologia , Comportamento Alimentar/fisiologia , Asseio Animal/fisiologia , Masculino , Camundongos , Tiroxina/sangue , Fatores de Tempo , Tri-Iodotironina/sangue
19.
J Exp Zool A Ecol Integr Physiol ; 333(7): 483-492, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32314557

RESUMO

High basal metabolic rate (BMR) is related to a powerful metabolic engine even under food shortage, which can lead to high levels of daily energy expenditure and requires more energy for maintenance in small mammals. To test the hypothesis that animals with different BMR levels respond differently to food shortage, we compared the changes in metabolism, morphology, and gene expression in response to food deprivation (FD) in male-striped hamsters (Cricetulus barabensis) with low (L)- or high (H)-BMR levels. After 36 hr of FD, energy expenditure, metabolic rate (MR), mass of body composition, and leptin and agouti-related peptide gene expressions in the white adipose tissues and the hypothalamus, respectively, decreased significantly in hamsters. The energy expenditure of H-BMR hamsters was reduced more than that of L-BMR hamsters after 36 hr of FD. Furthermore, MR was significantly reduced by FD, and that of the H-BMR group decreased more than that of the L-BMR group during the daytime. Therefore, our data suggest that striped hamsters with different BMR display different responses to variations in food availability. During FD, MR in H-BMR hamsters was more flexible than that in L-BMR animals and L-BMR hamsters could not reduce their MR any lower.


Assuntos
Metabolismo Basal/fisiologia , Cricetulus/fisiologia , Privação de Alimentos/fisiologia , Neuropeptídeos/metabolismo , Animais , Composição Corporal/fisiologia , Ritmo Circadiano , Cricetulus/metabolismo , Expressão Gênica , Masculino , RNA Mensageiro , Reação em Cadeia da Polimerase em Tempo Real/métodos
20.
Front Physiol ; 10: 469, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31068837

RESUMO

Most mammals and birds are altricial, small and naked at birth/hatching. They attain endothermic thermoregulation at a fraction of their adult size at a vulnerable stage with high heat loss when many could profit from using torpor for energy conservation. Nevertheless, detailed data on the interrelations between torpor expression and development of endothermic thermoregulation are currently restricted to <0.1% of extant endotherms. We investigated at what age and body mass (BM) desert hamsters (Phodopus roborovskii), wild-caught in Inner Mongolia and born in autumn/early winter when environmental temperatures in the wild begin to decrease, are able to defend their body temperature (Tb) at an ambient temperature (Ta) of ∼21°C and how soon thereafter they could express torpor. Measurements of surface temperatures via infrared thermometer and thermal camera show that although neonate hamsters (BM 0.9 ± 0.1 g) cooled rapidly to near Ta, already on day 15 (BM 5.5 ± 0.2 g) they could defend a high and constant Tb. As soon as day 16 (BM 5.8 ± 0.2 g), when their maximum activity metabolism (measured as oxygen consumption) approached maxima measured in vertebrates, animals were able to enter torpor for several hours with a reduction of metabolism by >90%, followed by endothermic arousal. Over the next weeks, torpor depth and duration decreased together with a reduction in resting metabolic rate at Ta 30-32°C. Our data show that development of endothermy and torpor expression in this altricial hamster is extremely fast. The results suggest that precocious torpor by juvenile hamsters in autumn and winter is an important survival tool in their vast and harsh Asian desert habitats, but likely also for many other small mammals and birds worldwide.

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