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1.
Int J Med Sci ; 18(4): 1015-1023, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33456359

RESUMEN

Huaier extract, the main active constituent proteoglycan, has anti-tumor activity in various experimental and clinical settings. However, the potential anti-neuroblastoma and associated mechanisms have not been investigated. Therefore, in this study, we aimed to elucidate the potential role of Huaier extract in 3 human neuroblastoma cell lines. Our study demonstrated that incubation with Huaier extract resulted in a marked decrease in cell viability in a dose-dependent manner. Huaier extract induced cell cycle arrest at G0/G1 phase in neuroblastoma and decreased the cell cycle related protein expression of cyclin D3. Western blotting analysis also showed that Huaier extract induced neuroblastoma cell apoptosis and autophagy. Signaling analysis indicated that Huaier extract suppressed the MEK/ERK and mTOR signaling pathways simultaneously. In conclusion, we verify that Huaier extract causes cell proliferation inhibition, apoptosis, autophagy, and cell cycle arrest in G0/G1 phase via MEK/ERK and mTOR signaling. Huaier extract may act as a complementary agent for treating neuroblastoma.


Asunto(s)
Mezclas Complejas/farmacología , Neuroblastoma/tratamiento farmacológico , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Mezclas Complejas/aislamiento & purificación , Mezclas Complejas/uso terapéutico , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Neuroblastoma/patología , Serina-Treonina Quinasas TOR/metabolismo , Trametes/aislamiento & purificación
2.
Res Sports Med ; 28(4): 553-562, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32686490

RESUMEN

We examined the effects of long-term exercise on age-related decline in static balance control through centre-of-pressure (CoP) measurements of four groups of participants: older controls, younger controls, older Tai Chi exercisers and older joggers. The participants stood quietly in a tandem stance on a force platform for 30 s with eyes open (EO) and eyes closed (EC). The older controls showed remarkably larger CoP and EC/EO ratios than younger controls and older Tai Chi exercisers. The EC/EO ratios of velocity in the mediolateral direction of older joggers were significantly smaller than those of older controls. Results suggest that the static balance of older controls showed a significant decline caused by age-related changes. Long-term Tai Chi and jogging, particularly the former, contributed to static balance control in older people. Older adults relied more on visual information in static postural control than young people. Tai Chi would be an ideal exercise for improving static balance in older people.


Asunto(s)
Ejercicio Físico/fisiología , Trote/fisiología , Equilibrio Postural/fisiología , Taichi Chuan , Adulto , Anciano , Envejecimiento/fisiología , Estudios Transversales , Humanos , Masculino , Factores de Tiempo , Percepción Visual/fisiología , Adulto Joven
3.
Gut ; 68(11): 2032-2043, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-30635406

RESUMEN

OBJECTIVE: Chronic hepatitis B (CHB) virus infection is a global health problem. Finding a cure for CHB remains a challenging task. DESIGN: In this study, poly I:C was employed as an adjuvant for HBV therapeutic vaccine (referred to as pHBV-vaccine) and the feasibility and efficiency of pHBV-vaccine in CHB treatment were evaluated in HBV-carrier mice. RESULTS: We found that pHBV-vaccine decreased HBsAg and HBV DNA efficiently and safely in HBV-carrier mice. Further investigation showed that pHBV-vaccine promoted maturation and antigen presentation ability of dendritic cells in vivo and in vitro. This vaccine successfully restored the exhaustion of antigen-specific CD8+ T cells and partly broke the immune tolerance established in HBV-carrier mice. pHBV-vaccine also enhanced the proliferation and polyfunctionality of HBV-specific CD11ahi CD8αlo cells. Importantly, we observed that T cell activation molecule KLRG1 was only expressed on HBV specific CD11ahi CD8αlo cells. Furthermore, pHBV-vaccine reduced the expression of Eomes and increased the serum IL-12 levels, which in turn promoted the generation of effector memory short-lived effector cells (SLECs) to exhibit a critical role in HBV clearance. SLECs induced by pHBV-vaccine might play a crucial role in protecting from HBV reinfection. CONCLUSIONS: Findings from this study provide a new basis for the development of therapeutic pHBV-vaccine, which might be a potential candidate for clinical CHB therapy.


Asunto(s)
Antivirales/uso terapéutico , Vacunas contra Hepatitis B/uso terapéutico , Hepatitis B Crónica/tratamiento farmacológico , Poli I-C/uso terapéutico , Animales , Linfocitos T CD8-positivos , Modelos Animales de Enfermedad , Hepatitis B Crónica/patología , Masculino , Ratones , Ratones Endogámicos C57BL
4.
Exp Cell Res ; 365(2): 177-184, 2018 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-29499203

RESUMEN

Neuroblastoma (NB) is one of the most common solid tumors in children. High-risk NB remains lethal in about 50% of patients despite comprehensive and intensive treatments. Activation of PI3K/Akt/mTOR signaling pathway correlates with oncogenesis, poor prognosis and chemotherapy resistance in NB. Due to its central role in growth and metabolism, mTOR seems to be an important factor in NB, making it a possible target for NB. In this study, we investigated the effect of AZD8055, a potent dual mTORC1-mTORC2 inhibitor, in NB cell lines. Our data showed that mTOR signaling was extensively activated in NB cells. The activity of mTOR and downstream molecules were down-regulated in AZD8055-treated NB cells. Significantly, AZD8055 effectively inhibited cell growth and induced cell cycle arrest, autophagy and apoptosis in NB cells. Moreover, AZD8055 significantly reduced tumor growth in mice xenograft model without apparent toxicity. Taken together, our results highlight the potential of mTOR as a promising target for NB treatment. Therefore, AZD8055 may be further investigated for treatment in clinical trials for high risk NB.


Asunto(s)
Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Morfolinas/farmacología , Neuroblastoma/tratamiento farmacológico , Neuroblastoma/patología , Animales , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Ratones , Ratones Desnudos , Morfolinas/uso terapéutico , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
5.
Biochem Biophys Res Commun ; 499(3): 425-432, 2018 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-29571732

RESUMEN

Mammalian target of rapamycin (mTOR) complex (mTORC) is frequently activated in diverse cancers. Although dual mTORC1/2 inhibitors are currently under development to treat various malignancies, the emergence of drug resistance has proven to be a major complication. AZD8055 is a novel, potent ATP-competitive and specific inhibitor of mTOR kinase activity, which blocks both mTORC1 and mTORC2 activation. In this study, we acquired AZD8055-resistant neuroblastoma (NB) cell sublines by using prolonged stepwise escalation of AZD8055 exposure (4-12 weeks). Here we demonstrate that the AZD8055-resistant sublines (TGW-R and SMS-KAN-R) exhibited marked resistance to AZD8055 compared to the parent cells (TGW and SMS-KAN). The cell cycle G1/S transition was advanced in resistant cells. In addition, the resistance against AZD8055 correlated with over-activation of MEK/ERK signaling pathway. Furthermore, combination of AZD8055 and MEK inhibitor U0126 enhanced the growth inhibition of resistant cells significantly in vitro and in vivo. In conclusion, these data show that targeting mTOR kinase and MEK/ERK signaling simultaneously might help to overcome AZD8055 resistance in NB.


Asunto(s)
Resistencia a Antineoplásicos/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Morfolinas/farmacología , Neuroblastoma/enzimología , Neuroblastoma/patología , Animales , Antineoplásicos/farmacología , Butadienos/farmacología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Inducción Enzimática/efectos de los fármacos , Femenino , Fase G1/efectos de los fármacos , Humanos , Ratones Desnudos , Nitrilos/farmacología , Fase S/efectos de los fármacos , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Serina-Treonina Quinasas TOR/metabolismo
6.
Mediators Inflamm ; 2018: 9289417, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30670930

RESUMEN

B-1a cells are distinguishable from conventional B cells, which are designated B-2 cells, on the basis of their developmental origin, surface marker expression, and functions. In addition to the unique expression of the CD5 antigen, B-1a cells are characterized by the expression level of CD23. Although B-1a cells are considered to be independent of T cells and produce natural autoantibodies that induce the clinical manifestations of autoimmune diseases, there is much debate on the role of B-1a cells in the development of autoimmune diseases. We examined the involvement of B-1a cells in autoimmune-prone mice with the lpr gene. MRL/lpr and B6/lpr mice exhibited lupus and lymphoproliferative syndromes because of the massive accumulation of CD3+CD4-CD8-B220+ T cells. Interestingly, the B220+CD23-CD5+ (B-1a) cell population in the peripheral blood and peritoneal cavity increased with age and disease progression. Ninety percent of B-1a cells were CD3 positive (CD3+ B-1a cells) and did not produce tumor necrosis factor alpha, interferon gamma, or interleukin-10. To test the possible involvement of CD3+ B-1a cells in autoimmune disease, we tried to eliminate the peripheral cells by hypotonic shock through repeated intraperitoneal injections of distilled water. The fraction of peritoneal CD3+ B-1a cells decreased, and symptoms of the autoimmune disease were much milder in the distilled water-treated MRL/lpr mice. These results suggest that CD3+ B-1a cells could be mediators of disease progression in autoimmune-prone mice.


Asunto(s)
Autoinmunidad/fisiología , Complejo CD3/metabolismo , Animales , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/metabolismo , Autoinmunidad/genética , Complejo CD3/genética , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/metabolismo , Línea Celular , Células Cultivadas , Progresión de la Enfermedad , Femenino , Ratones , Ratones Endogámicos C57BL , Receptores de IgE/metabolismo
7.
Res Sports Med ; 25(1): 111-117, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27868426

RESUMEN

This study examined the effects of regular Tai Chi practice and jogging on the neuromuscular activity of the trunk, hip, and ankle joint muscles of older people during lateral postural perturbation. A total of 42 older people participated in the study and formed the Tai Chi, jogging, and sedentary control groups. Electromyography signals were collected from the peroneus longus, anterior tibialis, gluteus medius, and erector spinae during unpredictable mediolateral perturbation. The Tai Chi group exhibited significantly faster latencies of the tibialis anterior and erector spinae than the control group. The jogging group showed a significantly shorter neuromuscular reaction time of the erector spinae than the control group. No significant difference was observed between the Tai Chi and jogging groups. Long-term regular Tai Chi practice enhanced the neuromuscular reaction of the erector spinae and tibialis anterior to lateral perturbation and will help timely posture correction when lateral postural distributions occur.


Asunto(s)
Trote/fisiología , Músculo Esquelético/fisiología , Equilibrio Postural/fisiología , Taichi Chuan , Anciano , Anciano de 80 o más Años , Articulación del Tobillo/fisiología , Estudios Transversales , Electromiografía , Articulación de la Cadera/fisiología , Humanos , Masculino , Desempeño Psicomotor , Tiempo de Reacción , Torso/fisiología
9.
Cancer Cell Int ; 15: 91, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26421002

RESUMEN

PURPOSE: AKT plays a pivotal role in the signal transduction of cancer cells. MK2206, an AKT inhibitor, has been shown to be an effective anti-cancer drug to a variety of cancer cell lines. However, some cancer cells acquire resistance to MK2206 and new strategies to suppress these cell lines remain to be developed. EXPERIMENTAL DESIGN: Acquired MK-2206-resistant neuroblastoma (NB) cell sublines were induced by stepwise escalation of MK-2206 exposure (4-12 weeks). MTT assay was used to validate cell proliferation. Flow cytometry was performed for cell cycle analysis. Western blot assay was used for cell signaling study. RESULTS: MK2206 (5-10 µmol) significantly suppressed cell growth of MK2206 non-resistant NB cells (LAN-1, KP-N-SIFA, NB-19 and SK-N-DZ), but is less efficient in inhibiting that of resistant sublines, even after 2-week MK2206-free incubation. MK2206 acted in mTOR-S6K dependent and independent methods. MK-2206 resistant sublines (LAN-1-MK, KP-N-SIFA-MK, and SK-N-DZ-MK) showed lower IC50 of GSK2334470 (PDK1 inhibitor). The cell growth of all sublines was prohibited by AZD8805 (mTOR inhibitor), with IC50 of AZD8805 3-10 times lower than MK2206 non-resistant cells. The signaling profiles of these resistant sublines were characterized by elevated PDK1-mTOR-S6K activity, accompanying by low phosphorylation of AKT compared with non-resistant counterparts. GSK2334470 and AZD8055 effectively inhibited phosphorylation of PDK1 and mTOR, respectively, and induced higher G0-G1 ratio in LAN-1-MK than that in LAN-1 as well. PDK1 and mTOR inhibitors effected on phosphorylation of GSK3ß in some of resistant sublines. CONCLUSION: NB cells can acquire MK2206 resistance after exposure for 4-12 weeks. Resistant cells feature reliance on PDK1-mTOR-S6K pathway and are more sensitive to PDK1 and mTOR inhibitors than the non-resistant counterparts. Thus, suppression of PDK1-mTOR-S6K signaling pathway is an effective way to overcome the MK2206 resistance, and this may be a promising strategy for targeted therapy.

10.
Zhong Yao Cai ; 37(11): 1938-46, 2014 Nov.
Artículo en Zh | MEDLINE | ID: mdl-26027111

RESUMEN

OBJECTIVE: To study the synergistic effect on hepatoma cell(SMMC-7721) and the reduction killing effect on normal liver cells(LO-2) treated with sodium cantharidinate (SCA) in combination with fluorouracil(5-FU) or cisplatin(DDP) as well as the related mechanism. METHODS: MTT assay was used to select the best ratio of SCA with 5-FU or SCA with DDP which had less toxicity on LO-2 cell line and had synergistic effect on SMMC-7721 cell line; Flow cytometry assay was used to analyze the apoptosis-induction of the different ratio of drugs on both cell lines; Hoechst-33258 fluorescent staining assay was used to observe the nuclear morphological changes of cells; Immunoblotting assay was used to analyze the Ras/Raf/ERK1/2 signaling pathway and the apoptosis related signaling pathway in both cell lines. RESULTS: MTI assay indicated that the proliferation inhibition of SCA,5-FU and DDP on SMMC-7721 cell line was in a time-and dose-dependent manner respectively. Among them, SCA had a more significant inhibition on SMMC-7721 cell line than on LO-2 after 12 h or 24 h treatment (P <0. 01). Moreover, after a treatment of 48 h,the ratio of 2. 5 µg/mL SCA and 2 µg/mL DDP showed a more significant inhibition on SMMC-7721 cell line than on LO-2 cell line,which was then be considered as the optimal concentration ratio for the following experiment. Co-treatment of SCA (2. 5 µg/mL) with DDP (2 µg/mL) induced a more significant apoptosis on SMMC-7721 cell line compared with single treatment with SCA (2. 5 µg/mL) or DDP (2 µg/mL) respectively (P < 0. 01). After a 48 h treatment of the optimal ratio of drugs, the significant morphological apoptotic characteristics were observed both under inverted microscope and by Hoechst-33258 fluorescent staining assay in both cell lines. The results of Western blot assay showed that this ratio of drugs could significantly increase the protein expression of Bax,P53 and P21 and decreased the expression of BCL-2, Casepase-3, p-Erk, p-Ras and p-c-Raf in SMMC-7721 cells. Meanwhile,the effect on the proteins mentioned above was lesser in LO-2 cells. CONCLUSION: These results indicates that 2. 5 µg/mL SCA + 2 µg/mL DDP showed a higher inhibition on the hepatic carcinoma cells and a relatively lower cytotoxicity on normal liver cells. The major anti-cancer mechanism is related with the inhibition on Erk signaling pathway and the induction of apoptosis through the mitochondrial pathway.


Asunto(s)
Antineoplásicos/farmacología , Cantaridina/farmacología , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Apoptosis , Línea Celular Tumoral/efectos de los fármacos , Cisplatino/farmacología , Citometría de Flujo , Fluorouracilo/farmacología , Humanos , Transducción de Señal
11.
Ergonomics ; 56(12): 1908-16, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24206277

RESUMEN

Twelve boys with an average age of 9.9 years were instructed to carry backpacks that weighed 0%, 10% and 15% of their body weights (BWs) to complete planned and unplanned gait termination experiments. The craniohorizontal, craniovertebral and sagittal shoulder posture angles at the sagittal plane as well as the anterior head alignment and coronal shoulder posture angles at the coronal plane were analysed. Results revealed significantly smaller craniohorizontal and sagittal shoulder posture angles during planned gait termination and a significantly smaller sagittal shoulder posture angle during unplanned gait termination under loaded conditions compared with those at 0% BW backpacks. Furthermore, the coronal shoulder posture angles at 10% and 15% BW during planned and unplanned gait terminations were significantly larger than those at 0% BW. Therefore, subjects were more likely to have a forward head posture, rounded shoulder posture and increased lateral tilting of the shoulders during gait termination as backpack loads were increased. However, gait termination, whether planned or unplanned, did not elicit a remarkable effect on posture.


Asunto(s)
Marcha/fisiología , Elevación , Postura/fisiología , Soporte de Peso/fisiología , Vértebras Cervicales/fisiología , Niño , Cabeza/fisiología , Humanos , Masculino , Hombro/fisiología
12.
Sports Biomech ; 10(2): 85-97, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21834393

RESUMEN

One important extrinsic factor that causes foot deformity and pain in women is footwear. Women's sports shoes are designed as smaller versions of men's shoes. Based on this, the current study aims to identify foot shape in 1,236 Chinese young adult men and 1,085 Chinese young adult women. Three-dimensional foot shape data were collected through video filming. Nineteen foot shape variables were measured, including girth (4 variables), length (4 variables), width (3 variables), height (7 variables), and angle (1 variable). A comparison of foot measures within the range of the common foot length (FL) categories indicates that women showed significantly smaller values of foot measures in width, height, and girth than men. Three foot types were classified, and distributions of different foot shapes within the same FL were found between women and men. Foot width, medial ball length, ball angle, and instep height showed significant differences among foot types in the same FL for both genders. There were differences in the foot shape between Chinese young women and men, which should be considered in the design of Chinese young adults' sports shoes.


Asunto(s)
Pie/anatomía & histología , Zapatos , Adolescente , Adulto , China , Análisis por Conglomerados , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Reproducibilidad de los Resultados , Factores Sexuales , Grabación en Video
13.
Zhong Yao Cai ; 34(11): 1753-6, 2011 Nov.
Artículo en Zh | MEDLINE | ID: mdl-22506404

RESUMEN

OBJECTIVE: To investigate the effect of 5-hydroxymethyl furfural (5-HMF) on apoptosis and BCL-2, NF-kappaB gene expression of rat hippocampal neurons injured by hydroperoxide (H2O2). METHODS: Hippocampal neurons of newly born rat were cultured in vivo and injured by H2O2. Effect of different concentration of 5-HMF on cell viability was measured by MTT. Flow cytometer (FCM) was used to measure the apoptosis of rat hippocampal neurons pre-cultured with different concentration of 5-HMF,Western blotting was used to measure the expression of BCL-2 and NF-kappaB gene. RESULTS: It revealed that the high and medium dosage of 5-HMF could increase the activity of rat hippocampal. The high, medium and low dosage of 5-HMF also increased the expression of BCL-2 gene and decreased the expression of NF-kappaB gene. CONCLUSION: 5-HMF could restrain the apoptosis of cultured hippocampal neurons injured by H2O2. The mechanism may be related to increasing in BCL-2 level and decreasing in NF-kappaB level.


Asunto(s)
Apoptosis/efectos de los fármacos , Cornus/química , Furaldehído/análogos & derivados , Hipocampo/citología , FN-kappa B/metabolismo , Neuronas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Animales , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Citometría de Flujo , Furaldehído/administración & dosificación , Furaldehído/farmacología , Peróxido de Hidrógeno , Neuronas/efectos de los fármacos , Neuronas/patología , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Sprague-Dawley
14.
Yi Chuan ; 32(9): 961-5, 2010 Sep.
Artículo en Zh | MEDLINE | ID: mdl-20870618

RESUMEN

Membrane fusion in vesicle trafficking in the cells of eukaryotic organisms is mediated by soluble-N-ethyl- maleimide-sensitive fusion protein attachment protein receptor (SNARE) proteins. OsNPSN11 is a member of Qb-SNARE gene family isolate from rice. The cDNA of OsNPSN11 was subcloned into pET-30a and fusion to the 6 × His tag. Induced by 0.5 mmol/L IPTG for four hours, the recombinant protein was highly expressed in Escherichia coli, which was purified by Ni2+ -NTA His-bind resin affinity chromatography column to be used as an antigen to raise the antibody in New Zealand rabbits. Western blotting analysis showed that the antibody can specifically recognize the expressed antigen and the OsNPSN11 in plasma membrane protein from various rice tissues. This indicated that the antibody can be used for expres-sion analysis in transgenic rice.


Asunto(s)
Anticuerpos/inmunología , Formación de Anticuerpos , Oryza/química , Proteínas Qb-SNARE/inmunología , Proteínas Recombinantes de Fusión/inmunología , Animales , Western Blotting , Proteínas Portadoras/química , Escherichia coli/genética , Conejos , Proteínas SNARE/inmunología
15.
In Vivo ; 34(5): 2381-2388, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32871763

RESUMEN

BACKGROUND/AIM: Huaier extract, whose main active constituent is the proteoglycan, has anti-tumor activity in several types of malignancies. In this study, we aimed to elucidate the effect of Huaier extract in hepatoblastoma cells. MATERIALS AND METHODS: The effect of Huaier extract on the proliferation of human hepatoblastoma cell lines HepG2 and HuH-6, was examined. RESULTS: Incubation with Huaier extract resulted in a marked, dose-dependent decrease in hepatoblastoma cell viability. Huaier extract induced S phase arrest in hepatoblastoma cells and upregulated the expression of the cell cycle related proteins cyclin D1 and cyclin D3. It also induced apoptosis in hepatoblastoma cells. Additionally, it significantly suppressed the activity of p-ERK and p-MEK. CONCLUSION: Huaier extract inhibits proliferation, and induces cell apoptosis and cell cycle arrest via the MEK-ERK pathway in hepatoblastoma cells. Huaier extract may act as a complementary agent for treating hepatoblastoma.


Asunto(s)
Hepatoblastoma , Neoplasias Hepáticas , Apoptosis , Línea Celular Tumoral , Proliferación Celular , Mezclas Complejas , Hepatoblastoma/tratamiento farmacológico , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Sistema de Señalización de MAP Quinasas , Quinasas de Proteína Quinasa Activadas por Mitógenos , Extractos Vegetales/farmacología , Transducción de Señal , Trametes
16.
Int J Biol Macromol ; 156: 1556-1564, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-31785296

RESUMEN

Myroilysin is a novel bacterial member of M12A metalloproteases family with an uncommon "cysteine switch" activation mechanism and a unique "cap" structure. However, activation of pro-myroilysin is elusive. Here, mature myroilysin was obtained for structure determination by treating pro-myroilysin with trypsin. The structure of mature myroilysin showed that the active-site zinc ion of the mature protein is coordinated by three histidine residues, a water molecule, and a tyrosine residue (Tyr208) in the conserved Met-turn motif (SIMHY). The "cap" structure moves away from the active-site to leave the active cleft open; the newly formed N-terminus is deeply buried in myroilysin, and Glu151 forms a salt bridge directly with the first amino acid residue (Gly38), whereas they are far from each other in the pro-myroilysin. The mutation of Tyr208 indicates that Tyr208 plays an important role in activity of myroilysin. The proteolytic activity and thermostability of mutant E151A decreased dramatically, implying that Glu151 is not only important for catalysis, but also crucial for structural stability in myroilysin. Structural comparison also reveals differences existed between myroilysin and astacin. Our biochemical and structural data provide new insights into the activation of myroilysin and functional involvement of crucial residues Tyr208 and Glu151.


Asunto(s)
Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Metaloproteasas/química , Metaloproteasas/metabolismo , Secuencias de Aminoácidos , Cristalografía por Rayos X , Activación Enzimática , Estabilidad de Enzimas
17.
Biochem Biophys Res Commun ; 389(3): 556-61, 2009 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-19751706

RESUMEN

ZFP245 is a cold- and drought-responsive gene that encodes a zinc finger protein in rice. The ZFP245 protein localizes in the nucleus and exhibits trans-activation activity. Transgenic rice plants overexpressing ZFP245 were generated and found to display high tolerance to cold and drought stresses. The transgenic plants did not exhibit growth retardation, but showed growth sensitivity against exogenous abscisic acid, increased free proline levels and elevated expression of rice pyrroline-5-carboxylatesynthetase and proline transporter genes under stress conditions. Overproduction of ZFP245 enhanced the activities of reactive oxygen species-scavenging enzymes under stress conditions and increased the tolerance of rice seedlings to oxidative stress. Our data suggest that ZFP245 may contribute to the tolerance of rice plants to cold and drought stresses by regulating proline levels and reactive oxygen species-scavenging activities, and therefore may be useful for developing transgenic crops with enhanced tolerance to abiotic stress.


Asunto(s)
Adaptación Fisiológica/genética , Regulación de la Expresión Génica de las Plantas , Oryza/fisiología , Proteínas de Plantas/genética , Dedos de Zinc/genética , Ácido Abscísico/farmacología , Frío , Sequías , Ornitina-Oxo-Ácido Transaminasa/metabolismo , Oryza/efectos de los fármacos , Oryza/genética , Estrés Oxidativo/genética , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/fisiología , Prolina/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Activación Transcripcional
18.
Res Sports Med ; 17(4): 205-16, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19967600

RESUMEN

This study examined the proprioception of the foot and ankle complex in regular ice hockey practitioners, runners, and ballet dancers. A total of 45 young people with different exercise habits formed four groups: the ice hockey, ballet dancing, running, and sedentary groups. Kinesthesia of the foot and ankle complex was measured in plantarflexion (PF), dorsiflexion (DF), inversion (IV), and eversion (EV) at 0.4 degrees /s using a custom-made device. The results showed the following: (1) significantly better perceived passive motion sense in PF/DF was found as compared with the measurements in IV/EV within each group (P < .01); (2) ice hockey and ballet groups perceived significantly better passive motion sense in IV/EV than the running (P < .05) and the sedentary (P < .01) groups; and (3) no significant difference in the all measurements was found between running and sedentary groups. The benefits of ice hockey and ballet dancing on proprioception may be associated with their movement characteristics.


Asunto(s)
Articulación del Tobillo/fisiología , Baile/fisiología , Hockey/fisiología , Propiocepción/fisiología , Carrera/fisiología , Análisis de Varianza , Fenómenos Biomecánicos , Índice de Masa Corporal , Femenino , Humanos , Masculino , Equilibrio Postural/fisiología , Rango del Movimiento Articular/fisiología , Adulto Joven
19.
Gene ; 420(2): 135-44, 2008 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-18588956

RESUMEN

The A20/AN1-type zinc finger protein family is conserved in animals and plants. Using human AWP1 protein as a query, we identified twelve A20/AN1-type zinc finger proteins in japonica rice. Most of these genes were constitutively expressed in leaves, roots, culms and spikes. Through microarray analysis, it was found that four genes (ZFP177, ZFP181, ZFP176, ZFP173), two genes (ZFP181 and ZFP176) and one gene (ZFP157) were significantly induced by cold, drought and H(2)O(2) treatments, respectively. Further expression analysis showed that ZFP177 was responsive to both cold and heat stresses, but down-regulated by salt. The subcellular localization assay indicated that ZFP177 was localized in cytoplasm in tobacco leaf and root cells. Yeast-one hybrid assay showed that ZFP177 lacked trans-activation potential in yeast cells. Overexpression of ZFP177 in tobacco conferred tolerance of transgenic plants to both low and high temperature stresses, but increased sensitivity to salt and drought stresses. Further we found expression levels of some stress-related genes were inhibited in ZFP177 transgenic plants. These results suggested that ZFP177 might play crucial but differential roles in plant responses to various abiotic stresses.


Asunto(s)
Adaptación Fisiológica/genética , Regulación de la Expresión Génica de las Plantas , Oryza/genética , Proteínas de Plantas/genética , Temperatura , Genes de Plantas , Oryza/metabolismo , Filogenia , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Proteínas de Plantas/análisis , Proteínas de Plantas/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Plantas Modificadas Genéticamente , Dedos de Zinc/genética
20.
FEBS Lett ; 582(7): 1037-43, 2008 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-18325341

RESUMEN

We previously identified a salt and drought stress-responsive TFIIIA-type zinc finger protein gene ZFP252 from rice. Here we report the functional analysis of ZFP252 using gain- and loss-of-function strategies. We found that overexpression of ZFP252 in rice increased the amount of free proline and soluble sugars, elevated the expression of stress defense genes and enhanced rice tolerance to salt and drought stresses, as compared with ZFP252 antisense and non-transgenic plants. Our findings suggest that ZFP252 plays an important role in rice response to salt and drought stresses and is useful in engineering crop plants with enhanced tolerance to salt and drought stresses.


Asunto(s)
Oryza/genética , Proteínas de Plantas/metabolismo , Factor de Transcripción TFIIIA/metabolismo , Metabolismo de los Hidratos de Carbono , Deshidratación , Expresión Génica , Genes de Plantas , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente/efectos de los fármacos , Plantas Modificadas Genéticamente/metabolismo , Prolina/metabolismo , Cloruro de Sodio/farmacología , Factor de Transcripción TFIIIA/genética
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