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1.
Plant Physiol ; 195(2): 1382-1400, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38345866

RESUMEN

Brassinosteroids (BRs) are phytohormones that regulate stomatal development. In this study, we report that BR represses stomatal development in etiolated Arabidopsis (Arabidopsis thaliana) cotyledons via transcription factors BRASSINAZOLE RESISTANT 1 (BZR1) and bri1-EMS SUPPRESSOR1 (BES1), which directly target MITOGEN-ACTIVATED PROTEIN KINASE KINASE 9 (MKK9) and FAMA, 2 important genes for stomatal development. BZR1/BES1 bind MKK9 and FAMA promoters in vitro and in vivo, and mutation of the BZR1/BES1 binding motif in MKK9/FAMA promoters abolishes their transcription regulation by BZR1/BES1 in plants. Expression of a constitutively active MKK9 (MKK9DD) suppressed overproduction of stomata induced by BR deficiency, while expression of a constitutively inactive MKK9 (MKK9KR) induced high-density stomata in bzr1-1D. In addition, bzr-h, a sextuple mutant of the BZR1 family of proteins, produced overabundant stomata, and the dominant bzr1-1D and bes1-D mutants effectively suppressed the stomata-overproducing phenotype of brassinosteroid insensitive 1-116 (bri1-116) and brassinosteroid insensitive 2-1 (bin2-1). In conclusion, our results revealed important roles of BZR1/BES1 in stomatal development, and their transcriptional regulation of MKK9 and FAMA expression may contribute to BR-regulated stomatal development in etiolated Arabidopsis cotyledons.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Brasinoesteroides , Cotiledón , Proteínas de Unión al ADN , Regulación de la Expresión Génica de las Plantas , Proteínas Nucleares , Estomas de Plantas , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Brasinoesteroides/metabolismo , Estomas de Plantas/crecimiento & desarrollo , Estomas de Plantas/genética , Estomas de Plantas/efectos de los fármacos , Cotiledón/genética , Cotiledón/crecimiento & desarrollo , Cotiledón/metabolismo , Cotiledón/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Mutación/genética , Regiones Promotoras Genéticas/genética , Etiolado , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Unión Proteica/efectos de los fármacos , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética
2.
J Cell Mol Med ; 26(23): 5767-5778, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36385733

RESUMEN

Platinum-based chemotherapy drugs play a very important role in the treatment of patients with advanced colorectal cancer, but the drug resistance of platinum-based chemotherapy drugs is an important topic that puzzles us. If we can find mechanisms of resistance, it will be revolutionary for us. We analysed the differential genes, core genes and their enrichment pathways in platinum-resistant and non-resistant patients through a public database. Platinum-resistant cell lines were cultured in vitro for in vitro colony and Transwell analysis. Tumorigenesis analysis of nude mice in vivo. Verify the function of core genes. Through differential gene and enrichment analysis, we found that CUL4B was the main factor affecting platinum drug resistance and EMT. Our hypothesis was further verified by in vitro drug-resistant and wild-type cell lines and in vivo tumorigenesis analysis of nude mice. CUL4B leads to platinum drug resistance in colorectal cancer by affecting tumour EMT.


Asunto(s)
Neoplasias Colorrectales , Resistencia a Antineoplásicos , Compuestos de Platino , Animales , Ratones , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Carcinogénesis , Transformación Celular Neoplásica , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Resistencia a Medicamentos/genética , Resistencia a Antineoplásicos/genética , Transición Epitelial-Mesenquimal/efectos de los fármacos , Transición Epitelial-Mesenquimal/genética , Ratones Desnudos , Compuestos de Platino/farmacología , Compuestos de Platino/uso terapéutico
3.
J Cell Mol Med ; 25(14): 6602-6617, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34075693

RESUMEN

N6-methyladenosine (m6A) is a well-known modification of RNA. However, as a key m6A methyltransferase, METTL16 has not been thoroughly studied in gastric cancer (GC). Here, the biological role of METTL16 in GC and its underlying mechanism was studied. Immunohistochemistry was used to detect the expression of METTL16 and relationship between METTL16 level and prognosis of GC was analysed. CCK8, colony formation assay, EdU assay and xenograft mouse model were used to study the effect of METTL16. Regulatory mechanism of METTL16 in the progression of GC was studied through flow cytometry analysis, RNA degradation assay, methyltransferase inhibition assay, RT-qPCR and Western blotting. METTL16 was highly expressed in GC cells and tissues and was associated with prognosis. In vitro and in vivo experiments confirmed that METTL16 promoted proliferation of GC cells and tumour growth. Furthermore, down-regulation of METTL16 inhibited proliferation by G1/S blocking. Significantly, we identified cyclin D1 as a downstream effector of METTL16. Knock-down METTL16 decreased the overall level of m6A and the stability of cyclin D1 mRNA in GC cells. Meanwhile, inhibition of methyltransferase activity reduced the level of cyclin D1. METTL16-mediated m6A methylation promotes proliferation of GC cells through enhancing cyclin D1 expression.


Asunto(s)
Proliferación Celular/genética , Ciclina D1/genética , Metiltransferasas/genética , Neoplasias Gástricas/genética , Adenosina/genética , Adulto , Anciano , Animales , Línea Celular Tumoral , Movimiento Celular/genética , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Xenoinjertos , Humanos , Masculino , Metilación , Ratones , Persona de Mediana Edad , Pronóstico , Estabilidad del ARN/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología
4.
Yi Chuan ; 42(12): 1211-1220, 2020 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-33509785

RESUMEN

Genetic drift is one of the four important factors affecting population genetic balance. Because its form of action is not as apparent as mutation, selection, and migration, which are intuitive and easy to understand, there are potential difficulties in understanding and mastering genetic drift. A particularly prominent problem is that the current introduction of genetic drift contents in textbooks is systematically insufficient. They are either even too rough, or completely neglecting the mathematical foundation such as the binomial theorem, resulting in long-term inadequate learning of genetic drift. In this paper, we summarize the five basic attributes of genetic drift, namely inherent, universal, random, non-directional, and regular features. Based on the concept that the genetic basis of genetic drift is the free combination of male and female gametes, we pointed out that the attribute of random sampling error is the inherent essential feature of genetic drift. Then step by step, from an extremely small population consisting of only one individual (N = 1), we deduced that the effect of genetic drift decreased while population size increased. Through introducing the mathematical model of the binomial theorem, the characteristics of the binomial distribution, and the results of computer simulations, the effect of genetic drift is visually and intuitively displayed to help the teaching the concept of genetic drift.


Asunto(s)
Flujo Genético , Genética de Población , Genética/educación , Frecuencia de los Genes , Modelos Genéticos , Selección Genética
5.
Yi Chuan ; 41(11): 1067-1072, 2019 Nov 20.
Artículo en Zh | MEDLINE | ID: mdl-31735709

RESUMEN

Genetic analysis is an important part of undergraduate genetics teaching and tetrad analysis is unique and integral for genetic analysis of fungi. The ordered tetrad in Neurospora is an important material for genetic analysis, which can not only be used to study recombination between genes and centromeres, but also between genes themselves, as well as study the fine cross patterns between non-sister chromatids of homologous chromosomes. However, in textbooks and related professional journals, there is a lack of specific introduction to the induction methods of the seven basic class asci used in two genes analysis. In the present paper, we designed a table presenting the correlation between the three tetrad types (PD, NPD, T) and the four segregation pattern groups (Ⅰ Ⅰ, Ⅱ Ⅱ, Ⅰ Ⅱ, Ⅱ Ⅰ) to visually show the 12 possible combinations (3×4=12). Then five of them were excluded through the "×" symbol and in addition with three comments attached with the table, thus finally we obtained seven basic ascus types. We hope that this analytical method can assist the teaching of ordered tetrad analysis in Neurospora.


Asunto(s)
Segregación Cromosómica , Neurospora/genética , Centrómero , Meiosis
6.
Molecules ; 23(7)2018 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-29958431

RESUMEN

A high-performance liquid chromatography (HPLC) method was investigated for the simultaneous quantification of two chemical types of bioactive compounds in the rhizome of Curcuma longa Linn. (turmeric), including three curcuminoids: Curcumin, bisdemethoxycurcumin, and demethoxycurcumin; and three volatile components: ar-turmerone, ß-turmerone, and α-turmerone. In the present study, the sample extraction system was optimized by a pressurized liquid extraction (PLE) process for further HPLC analysis. The established HPLC analysis conditions were achieved using a Zorbax SB-C18 column (250 mm × 4.6 mm i.d., 5 µm) and a gradient mobile phase comprised of acetonitrile and 0.4% (v/v) aqueous acetic acid with an eluting rate of 1.0 mL/min. The curcuminoids and volatile components were detected at 430 nm and 240 nm, respectively. Moreover, the method was validated in terms of linearity, sensitivity, precision, stability and accuracy. The validated method was successfully applied to evaluate the quality of twelve commercial turmeric samples.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Curcuma/química , Extractos Vegetales/química , Curcumina/análogos & derivados , Curcumina/química , Diarilheptanoides , Cetonas/química , Reproducibilidad de los Resultados , Rizoma/química , Sesquiterpenos/química
7.
Plant Cell Rep ; 36(7): 1053-1064, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28405745

RESUMEN

KEY MESSAGE: An albinic rice is caused by mutation of threonyl-tRNA synthetase, which is essential for plant development by stabilizing of NEP and PEP gene expressions and chloroplast protein synthesis. Chloroplast biogenesis and development depend on complex genetic mechanisms. Apart from their function in translation, aminoacyl-tRNA synthetases (aaRSs) play additional role in gene expression regulation, RNA splicing, and cytokine activity. However, their detailed functions in plant development are still poorly understood. We isolated a lethal albinic seedling (las) mutant in rice. Physiological and ultrastructural analysis of las mutant plants revealed weak chlorophyll fluorescence, negligible chlorophyll accumulation, and defective thylakoid membrane development. By map based cloning we determined that the LAS allele gene encodes threonyl-tRNA synthetase (ThrRS). LAS was constitutively expressed with relatively high level in leaves. NEP-dependent gene transcripts accumulated in the developing chloroplasts, while PEP-dependent transcripts were reduced in the las mutant. This result indicated that PEP activity was impaired. Chloroplast-encoded protein levels were sharply reduced in the las mutant. Biogenesis of chloroplast rRNAs (16S and 23S rRNA) was arrested, leading to impaired translation and protein synthesis. Together, our findings indicated that LAS is essential not only for chloroplast development by stabilizing the NEP and PEP gene expression, but also for protein synthesis and construction of the ribosome system in rice chloroplasts.


Asunto(s)
Oryza/enzimología , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Plantones/enzimología , Plantones/metabolismo , Treonina-ARNt Ligasa/metabolismo , Proteínas de Cloroplastos/genética , Proteínas de Cloroplastos/metabolismo , Cloroplastos/genética , Cloroplastos/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Genes de Plantas/genética , Mutación , Oryza/genética , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Plastidios/enzimología , Plastidios/genética , Plastidios/metabolismo , Plantones/genética , Treonina-ARNt Ligasa/genética
8.
Mol Pharm ; 13(11): 3613-3625, 2016 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-27768322

RESUMEN

Hepatocellular carcinoma (HCC) is an aggressive malignancy and the second leading cause of cancer death worldwide. Most current therapeutic agents lack the tumor-targeting efficiency and result in a nonselective biodistribution in the body. In our previous study, we identified a peptide Ala-Pro-Asp-Thr-Lys-Thr-Gln (APDTKTQ) that can selectively bind to the receptor of advanced glycation end-products (RAGE), an immunoglobulin superfamily cell surface molecule overexpressed during HCC malignant progression. Here, we report the design of a mixed micelles system modified with this peptide to target HCC cells. Specifically, we modified Pluronic F68 (F68) with APDTKTQ (F68-APDTKTQ), and we conjugated d-α-tocopheryl polyethylene glycol succinate (TPGS) with poly(lactic-co-glycolic acid) (PLGA) by a disulfide linker (TPGS-S-S-PLGA). We mixed TPGS-S-S-PLGA and F68-APDTKTQ (TSP/FP) to form a micelle, followed by the loading of oridonin (ORI). The prepared micelles showed a homogeneously spherical shape without aggregation, triggered an increased cellular uptake, and induced apoptosis in more cells than did the free ORI. Taken together, these results demonstrate the potential of this APDTKTQ-modified ORI-loaded TSP/FP mixed micelle system as a promising strategy for HCC-targeting therapy.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Productos Finales de Glicación Avanzada/metabolismo , Neoplasias Hepáticas/metabolismo , Apoptosis/efectos de los fármacos , Western Blotting , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Diterpenos de Tipo Kaurano/química , Diterpenos de Tipo Kaurano/farmacología , Sistemas de Liberación de Medicamentos , Células Hep G2 , Humanos , Ácido Láctico/química , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Micelas , Nanopartículas/química , Oxidación-Reducción/efectos de los fármacos , Péptidos/química , Poloxámero , Polietilenglicoles/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico
9.
Artículo en Inglés | MEDLINE | ID: mdl-27470945

RESUMEN

It has been well known that metabolic thermogenesis plays an important role in the thermoregulation of small mammals under different temperatures, while its role in fat accumulation is far from clear. In the present study, several physiological, hormonal, and biochemical measures indicative of metabolic thermogenesis were measured in the weaning striped hamsters after acclimated to a warm condition (30°C) for 1, 3 and 4months. The warm-acclimated groups significantly decreased energy intake, and simultaneously decreased nonshivering thermogenesis compared to those housed at 21°C. Body fat content increased by 29.9%, 22.1% and 19.6% in the hamsters acclimated to 1, 3 or 4months, respectively relative to their counterparts maintain at 21°C (P<0.05). The cytochrome c oxidase (COX) activity of brain, liver, heart and skeletal muscle, and the ratio of serum tri-iodothyronine to thyroxine significantly decreased in warm-acclimated groups compared with 21°C group. COX activity and uncoupling protein 1 (UCP1) mRNA expression of brown adipose tissue (BAT) were significantly down-regulated under the warm conditions. COX activity of BAT, liver, heart and muscle were significantly negatively correlated with body fat content, and the correlation between UCP1 expression and body fat content tended to be negative. These findings suggest that the decrease in the energy spent on metabolic thermogenesis plays an important role in the fat accumulation. The attenuation of COX and UCP1-based BAT activity may be involved in body fat accumulation in animals under warm conditions.


Asunto(s)
Aclimatación/fisiología , Tejido Adiposo Pardo/anatomía & histología , Tejido Adiposo Pardo/fisiología , Cricetinae/anatomía & histología , Cricetinae/fisiología , Termogénesis/fisiología , Aclimatación/genética , Animales , Metabolismo Basal , Composición Corporal , Cricetinae/genética , Regulación hacia Abajo , Complejo IV de Transporte de Electrones/metabolismo , Ingestión de Energía , Proteínas Mitocondriales/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Termogénesis/genética , Hormonas Tiroideas/sangre , Distribución Tisular , Proteína Desacopladora 1/genética
10.
Sci Technol Adv Mater ; 17(1): 109-114, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27877862

RESUMEN

In this study, we report the use of a cyclometalated luminescent iridium(III) complex for the visualization of thiols. The detection of glutathione (GSH) by complex 1 is achieved through the reduction of its phendione N^N donor, which influences the metal-to-ligand charge-transfer (MLCT) of the complex. Complex 1 produced a maximum threefold luminescence enhancement at 587 nm in response to GSH. The linear detection range of 1 for GSH is between 0.2 and 2 M equivalents of GSH, with a detection limit of 1.67 µM. Complex 1 also displays good selectivity for thiols over other amino acids.

11.
J Therm Biol ; 58: 72-9, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27157336

RESUMEN

It has been suggested that the up-regulation of uncoupling proteins (UCPs) decreases reactive oxygen species (ROS) production, in which case there should be a negative relationship between UCPs expression and ROS levels. In this study, the effects of temperature and food restriction on ROS levels and metabolic rate, UCP1 mRNA expression and antioxidant levels were examined in the brown adipose tissue (BAT) of the striped hamsters (Cricetulus barabensis). The metabolic rate and food intake of hamsters which had been restricted to 80% of ad libitum food intake, and acclimated to a warm temperature (30°C), decreased significantly compared to a control group. Hydrogen peroxide (H2O2) levels were 42.9% lower in food restricted hamsters than in the control. Malonadialdehyde (MDA) levels of hamsters acclimated to 30°C that were fed ad libitum were significantly higher than those of the control group, but 60.1% lower than hamsters that had been acclimated to the same temperature but subject to food restriction. There were significantly positive correlations between H2O2 and, MDA levels, catalase activity, and total antioxidant capacity. Cytochrome c oxidase activity and UCP1 mRNA expression significantly decreased in food restricted hamsters compared to the control. These results suggest that warmer temperatures increase oxidative stress in BAT by causing the down-regulation of UCP1 expression and decreased antioxidant activity, but food restriction may attenuate the effects.


Asunto(s)
Aclimatación , Tejido Adiposo Pardo/fisiología , Cricetulus/fisiología , Ayuno/fisiología , Estrés Oxidativo , Animales , Metabolismo Basal , Catalasa/metabolismo , Cricetinae , Regulación hacia Abajo , Ingestión de Alimentos , Complejo IV de Transporte de Electrones/metabolismo , Calor , Peróxido de Hidrógeno/metabolismo , Masculino , Malondialdehído/metabolismo , ARN Mensajero/genética , Especies Reactivas de Oxígeno/metabolismo , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
12.
Yi Chuan ; 38(1): 82-9, 2016 01.
Artículo en Zh | MEDLINE | ID: mdl-26787526

RESUMEN

Genetic drift is one of the difficulties in teaching genetics due to its randomness and probability which could easily cause conceptual misunderstanding. The "sampling error" in its definition is often misunderstood because of the research method of "sampling", which disturbs the results and causes the random changes in allele frequency. I analyzed and compared the definitions of genetic drift in domestic and international genetic textbooks, and found that the definitions containing "sampling error" are widely adopted but are interpreted correctly in only a few textbooks. Here, the history of research on genetic drift, i.e., the contributions of Wright, Fisher and Kimura, is introduced. Moreover, I particularly describe two representative articles recently published about genetic drift teaching of undergraduates, which point out that misconceptions are inevitable for undergraduates during the studying process and also provide a preliminary solution. Combined with my own teaching practice, I suggest that the definition of genetic drift containing "sampling error" can be adopted with further interpretation, i.e., "sampling error" is random sampling among gametes when generating the next generation of alleles which is equivalent to a random sampling of all gametes participating in mating in gamete pool and has no relationship with artificial sampling in general genetics studies. This article may provide some help in genetics teaching.


Asunto(s)
Flujo Genético , Genética/educación , Frecuencia de los Genes , Genética de Población , Humanos , Modelos Genéticos , Estudiantes , Enseñanza , Recursos Humanos
13.
Horm Behav ; 65(4): 355-62, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24631583

RESUMEN

Physiological and behavioral adjustments of small mammals are important strategies in response to variations in food availability. Although numerous of studies have been carried out in rodents, behavioral patterns in response to food deprivation and re-feeding (FD-RF) are still inconsistent. Here we examined effects of a 24h FD followed by RF on general activity, serum leptin concentrations and gene expression of orexigenic and anorexigenic hypothalamic neuropeptides in striped hamsters (Cricetulus barabensis) with/without leptin supplements. The time spent on activity was increased by 2.5 fold in FD hamsters compared with controls fed ad libitum (P<0.01). Body mass, fat mass as well as serum leptin concentrations were significantly decreased in FD hamsters in comparison with ad libitum controls, which were in parallel with hyperactivity. During re-feeding, leptin concentrations increased rapidly to pre-deprivation levels by 12h, but locomotor activity decreased gradually and did not return to pre-deprivation levels until 5days after re-feeding. Leptin administration to FD hamsters significantly attenuated the increased activity. Gene expression of hypothalamic neuropeptide Y (NPY) was upregulated in FD hamsters and fell down to control levels when hamsters were re-fed ad libitum, similar to that observed in activity behavior. Leptin supplement induced increases in serum leptin concentrations (184.1%, P<0.05) in FD hamsters and simultaneously attenuated the increase in activity (45.8%, P<0.05) and NPY gene expression (35%, P<0.05). This may allow us to draw a more generalized conclusion that decreased leptin concentrations function as a starvation signal in animals under food shortage; to induce an increase in activity levels, leading animals to forage and/or migrate, and consequently increasing the chance of survival. Decreased concentrations of serum leptin in animals subjected to food shortage may induce an upregulation of gene expression of hypothalamus NPY, consequently driving a significant increase in foraging behavior.


Asunto(s)
Cricetulus/metabolismo , Privación de Alimentos/fisiología , Regulación de la Expresión Génica/fisiología , Leptina/sangre , Actividad Motora/fisiología , Neuropéptido Y/metabolismo , Animales , Conducta Animal/efectos de los fármacos , Conducta Animal/fisiología , Regulación de la Expresión Génica/efectos de los fármacos , Hipotálamo/metabolismo , Leptina/farmacología , Actividad Motora/efectos de los fármacos , Distribución Aleatoria
14.
Inorg Chem ; 53(21): 11498-506, 2014 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-25333867

RESUMEN

A novel "turn-on" phosphorescent chemodosimeter based on a cyclometalated Ir(III) complex has been designed and synthesized, which displays high selectivity and sensitivity toward Hg(2+) in aqueous media with a broad pH range of 4-10. Furthermore, by time-resolved photoluminescence techniques, some interferences from the short-lived background fluorescence can be eliminated effectively and the signal-to-noise ratio of the emission detection can be improved distinctly by using the chemodosimeter. Finally, the chemodosimeter can be used to monitor Hg(2+) effectively in living cells by confocal luminescence imaging.


Asunto(s)
Complejos de Coordinación/química , Iridio/química , Mediciones Luminiscentes , Mercurio/análisis , Supervivencia Celular/efectos de los fármacos , Complejos de Coordinación/síntesis química , Relación Dosis-Respuesta a Droga , Humanos , Concentración de Iones de Hidrógeno , Estructura Molecular , Teoría Cuántica , Relación Estructura-Actividad , Factores de Tiempo , Células Tumorales Cultivadas
15.
J Therm Biol ; 44: 35-40, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25086971

RESUMEN

The mechanism of the rate of living-free radical theory suggests that higher rate of oxidative metabolism results from greater rate of mitochondria oxidative phosphorylation, leading to a consequent increase in production of free radicals. However, the relation between metabolic rate and oxidative stress is tissue dependent in animals acclimated to cold temperatures. Here we examined oxidative stress, reflected by changes of antioxidant activity and other related markers, in striped hamsters acclimated to moderate cold (15°C), room (23°C) or warm temperature (30°C) for 6 weeks, by which either higher or lower metabolic rate was induced experimentally. Energy intake and the rate of metabolism and nonshivering thermogenesis were increased at 15°C, but decreased at 30°C compared with that at 23°C. Effects of temperatures on the markers of both oxidative stress and antioxidant activities were rarely significant. The percentages of positive correlation between the 11 tissues (brain, BAT, liver, heart, lung, kidneys, stomach, small and large intestine, caecum and skeletal muscle) were 14.5% (8/55) for catalase (CAT), 7.3% (4/55) for the capacity of inhibition of hydroxyl free radical (CIH), 5.5% (3/55) for activities of superoxide dismutase (SOD), 1.8% (1/55) for total antioxidant capacity (T-AOC), 4.3% (2/46) for H2O2 and 11.1% (4/36) for the capacity of inhibition of hydroxyl free radical (CIH). This indicated that the tissue-dependent changes of both oxidative stress and antioxidant activity were less consistent among the different tissues. Finally the data from this study were less consistent with the prediction of the mechanism of the rate of living-free radical theory.


Asunto(s)
Aclimatación/fisiología , Metabolismo Basal , Temperatura Corporal , Frío , Estrés Oxidativo , Termogénesis , Animales , Catalasa/metabolismo , Cricetinae , Radicales Libres/metabolismo , Especificidad de Órganos , Superóxido Dismutasa
16.
Free Radic Biol Med ; 215: 2-13, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38395090

RESUMEN

As mitochondrial damage or dysfunction is commonly observed following burn injuries, we investigated whether mitochondrial transplantation (MT) can result in therapeutic benefits in the treatment of burns. Human immortalized epidermal cells (HaCaT) and Kunming mice were used to establish a heat-injured cell model and a deep partial-thickness skin burn animal model, respectively. The cell model was established by exposing HaCaT cells to 45 or 50 °C for 10 min, after which cell proliferation was assayed using fluorescent double-staining and colony formation assays, cell migration was assessed using colloidal gold migration and scratch assays, and cell cycle progression and apoptosis were measured by flow cytometry. Histopathological staining, immunohistochemistry, nick-end labeling analysis, and enzyme-linked immunosorbent assays were used to evaluate the effects of MT on inflammation, tissue recovery, apoptosis, and scar growth in a mouse model. The therapeutic effects were observed in the heat-injured HaCaT cell model. MT promoted cell viability, colony formation, proliferation, and migration; decreased G1 phase; promoted cell division; and decreased apoptosis. Wound-healing promotion, anti-inflammation (decreased mast cell aggregation, down-regulated of TNF-α, IL-1ß, IL-6, and up-regulated IL-10), acceleration of proliferation recovery (up-regulated CD34 and VEGF), apoptosis reduction, and scar formation reduction (decreased collagen I/III ratio and TGF-ß1) were observed in the MT mouse model. The MT mode of action was, however, not investigated in this study. In conclusion, our data indicate that MT exerts a therapeutic effect on burn injuries both in vitro and in vivo.


Asunto(s)
Quemaduras , Cicatriz , Ratones , Animales , Humanos , Cicatrización de Heridas , Piel/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Quemaduras/terapia , Quemaduras/metabolismo
17.
Anim Sci J ; 95(1): e13964, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38831612

RESUMEN

This study evaluated the effects of supplementation with Antrodia cinnamomea mycelium by-product (ACBP) on growth performance and immune response in weaning piglets. Total available content and antioxidant capacity of ACBP were determined. Ninety-six black pigs were randomly distributed to 24 pens. Study compared four groups which were supplemented with ACBP at 0%, 2.5%, 5%, or 10% for 6 weeks after weaning at 4 weeks. Results showed that ACBP on total phenolic, total flavonoid, and total triterpenoids contents were 13.68 mg GAE/g DW, 1.67 µg QE/g DW, and 15.6 mg/g, respectively. Weaning piglets fed 2.5% ACBP showed a significant decreased body weight gain compared with those supplemented with 5% ACBP, 10% ACBP, and control groups. Results showed that all ACBP groups increased the villi height of jejunum significantly. Incidence of diarrhea in 11 weeks with supplementation with 5% and 10% ACBP diets were lower than in control group. The 10% ACBP group showed significantly lower expression of immune response genes (IL-1ß, IL-6, IL-8, TNF-α, and IFN-γ) than the 2.5% and 5% ACBP groups. Based on results, dietary supplementation with 10% ACBP did not significantly affect body weight but could decrease piglet diarrhea condition and expression of IL-1ß and IL-6 genes.


Asunto(s)
Alimentación Animal , Antioxidantes , Dieta , Suplementos Dietéticos , Micelio , Destete , Aumento de Peso , Animales , Porcinos/crecimiento & desarrollo , Porcinos/inmunología , Aumento de Peso/efectos de los fármacos , Dieta/veterinaria , Antioxidantes/metabolismo , Diarrea/veterinaria , Triterpenos/farmacología , Triterpenos/administración & dosificación , Expresión Génica/efectos de los fármacos , Citocinas/metabolismo , Yeyuno/metabolismo , Fenoles/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Enfermedades de los Porcinos/microbiología , Enfermedades de los Porcinos/prevención & control , Enfermedades de los Porcinos/inmunología , Polyporales/química
18.
Adv Sci (Weinh) ; 11(6): e2305913, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38059822

RESUMEN

Surgical removal of the thyroid gland (TG) for treating thyroid disorders leaves the patients on lifelong hormone replacement that partially compensates the physiological needs, but regenerating TG is challenging. Here, an approach is reported to regenerate TG within the spleen for fully restoring the thyroid's functions in mice, by transplanting thyroid tissue blocks to the spleen. Within 48 h, the transplanted tissue efficiently revascularizes, forming thyroid follicles similar to the native gland after 4 weeks. Structurally, the ectopically generated thyroid integrates with the surrounding splenic tissue while maintaining its integrity, separate from the lymphatic tissue. Functionally, it fully restores the native functions of the TG in hormone regulation in response to physiological stimuli, outperforming the established method of oral levothyroxine therapy in maintaining systemic homeostasis. The study demonstrates the full restoration of thyroid functions post-thyroidectomy by intrasplenic TG regeneration, providing fresh insights for designing novel therapies for thyroid-related disorders.


Asunto(s)
Neoplasias de la Tiroides , Tiroidectomía , Humanos , Animales , Ratones , Tiroidectomía/métodos , Neoplasias de la Tiroides/cirugía , Bazo/cirugía , Regeneración , Hormonas
19.
Plant Commun ; 5(7): 100891, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38561965

RESUMEN

Plants that grow in extreme environments represent unique sources of stress-resistance genes and mechanisms. Ammopiptanthus mongolicus (Leguminosae) is a xerophytic evergreen broadleaf shrub native to semi-arid and desert regions; however, its drought-tolerance mechanisms remain poorly understood. Here, we report the assembly of a reference-grade genome for A. mongolicus, describe its evolutionary history within the legume family, and examine its drought-tolerance mechanisms. The assembled genome is 843.07 Mb in length, with 98.7% of the sequences successfully anchored to the nine chromosomes of A. mongolicus. The genome is predicted to contain 47 611 protein-coding genes, and 70.71% of the genome is composed of repetitive sequences; these are dominated by transposable elements, particularly long-terminal-repeat retrotransposons. Evolutionary analyses revealed two whole-genome duplication (WGD) events at 130 and 58 million years ago (mya) that are shared by the genus Ammopiptanthus and other legumes, but no species-specific WGDs were found within this genus. Ancestral genome reconstruction revealed that the A. mongolicus genome has undergone fewer rearrangements than other genomes in the legume family, confirming its status as a "relict plant". Transcriptomic analyses demonstrated that genes involved in cuticular wax biosynthesis and transport are highly expressed, both under normal conditions and in response to polyethylene glycol-induced dehydration. Significant induction of genes related to ethylene biosynthesis and signaling was also observed in leaves under dehydration stress, suggesting that enhanced ethylene response and formation of thick waxy cuticles are two major mechanisms of drought tolerance in A. mongolicus. Ectopic expression of AmERF2, an ethylene response factor unique to A. mongolicus, can markedly increase the drought tolerance of transgenic Arabidopsis thaliana plants, demonstrating the potential for application of A. mongolicus genes in crop improvement.


Asunto(s)
Sequías , Fabaceae , Genoma de Planta , Fabaceae/genética , Fabaceae/fisiología , Estrés Fisiológico/genética , Evolución Molecular , Regulación de la Expresión Génica de las Plantas , Filogenia
20.
Pharmazie ; 68(5): 369-75, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23802436

RESUMEN

Kushen, the dried root of Sophora flavescens Ait, is a traditional Chinese herbal medicine. Kushen alkaloids have been developed in China as anticancer drugs, and more potent antitumor activities have been identified in kushen flavonoids than in kushen alkaloids. In this study, the anti-angiogenic properties of (2S)-7,2',4'-triihydroxy-5-methoxy-8-dimethylallyl flavanone (Compound 1, a novel flavonoid isolated from Kushen), were examined using the human umbilical vein endothelial cell line (ECV304) in vitro. The results indicated that compound 1 shows anti-angiogenesis activity via inhibitory effects on cell proliferation, cell migration, cell adhesion, and tube formation. Further studies indicated that compound 1 blocks cell cycles in the G0/G1 phase without inducing apoptosis, and down regulates vascular endothelial growth factor (VEGF) expression. The free radical scavenging activity of compound 1 was found through 2',7'-dichlorofluorescin diacetate (DCFH-DA) incubation assay in cells. The anti-angiogenic properties of compound 1 and its antiproliferative effect on endothelial cells without causing apoptosis make it a good candidate for development as a agent against development of tumors.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Flavonoides/farmacología , Fase G1/efectos de los fármacos , Fase de Descanso del Ciclo Celular/efectos de los fármacos , Sophora/química , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Antioxidantes/farmacología , Adhesión Celular/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Medicamentos Herbarios Chinos , Células Endoteliales/efectos de los fármacos , Flavonoides/aislamiento & purificación , Humanos , Microtúbulos/efectos de los fármacos , Raíces de Plantas/química , Especies Reactivas de Oxígeno/metabolismo
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