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1.
J Agric Food Chem ; 70(7): 2231-2240, 2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35148079

RESUMEN

Oleanane-type ginsenosides are highly biologically active substances in Panax ginseng, a popular Chinese dietary plant. Lack of key enzymes for glycosylation reactions has hindered de novo synthesis of these bioactive molecules. We mined candidate glycosyltransferases (GTs) of the ginseng database by combining key metabolites and transcriptome coexpression analyses and verified their function using in vitro enzymatic assays. The PgCSyGT1, a cellulose synthase-like GT rather than a UDP-dependent glucuronosyltransferase (UGT), was verified as the key enzyme for transferring a glucuronosyl moiety to the free C3-OH of oleanolic acid to synthesize calenduloside E. Two UGTs (PgUGT18 and PgUGT8) were first identified as, respectively, catalyzing the glycosylation reaction of the second sugar moiety of C3 and the C28 in the oleanane-type ginsenoside biosynthetic pathway. Then, we integrated these GTs in combinations into Saccharomyces cerevisiae genome and realized de novo biosynthesis of oleanane-type ginsenosides with a yield of 1.41 µg/L ginsenoside Ro in shake flasks. This report provides a basis for effective biosynthesis of diverse oleanane-type ginsenosides in microbial cell factories.


Asunto(s)
Ginsenósidos , Ácido Oleanólico , Panax , Glicosiltransferasas/genética , Glicosiltransferasas/metabolismo , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
2.
World J Gastroenterol ; 27(34): 5737-5752, 2021 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-34629798

RESUMEN

BACKGROUND: Identifying novel colorectal cancer (CRC) prognostic biomarkers is crucial to helping clinicians make appropriate therapy decisions. Melatonin plays a major role in managing the circadian rhythm and exerts oncostatic effects on different kinds of tumours. AIM: To explore the relationship between MTNR1B single-nucleotide polymorphism (SNPs) combined with gene hypermethylation and CRC prognosis. METHODS: A total of 94 CRC tumour tissues were investigated. Genotyping for the four MTNR1B SNPs (rs1387153, rs2166706, rs10830963, and rs1447352) was performed using multiplex polymerase chain reaction. The relationships between the MTNR1B SNPs and CRC 5-year overall survival (OS) was assessed by calculating hazard ratios with 95%CIs. RESULTS: All SNPs (rs1387153, rs2166706, rs10830963, and rs1447352) were correlated with decreased 5-year OS. In stratified analysis, rs1387153, rs10830963, and rs1447352 risk genotype combined with CDKN2A and MGMT methylation status were associated with 5-year OS. A strong cumulative effect of the four polymorphisms on CRC prognosis was observed. Four haplotypes of MTNR1B SNPs were also associated with the 5-year OS. MTNR1B SNPs combined with CDKN2A and MGMT gene methylation status could be used to predict shorter CRC survival. CONCLUSION: The novel genetic biomarkers combined with epigenetic biomarkers may be predictive tool for CRC prognosis and thus could be used to individualise treatment for patients with CRC.


Asunto(s)
Neoplasias Colorrectales , Metilación de ADN , Neoplasias Colorrectales/genética , Inhibidor p16 de la Quinasa Dependiente de Ciclina , Metilasas de Modificación del ADN/genética , Enzimas Reparadoras del ADN/genética , Humanos , Polimorfismo de Nucleótido Simple , Pronóstico , Receptor de Melatonina MT2/genética , Taiwán/epidemiología , Proteínas Supresoras de Tumor/genética
3.
Artículo en Inglés | MEDLINE | ID: mdl-32708017

RESUMEN

BACKGROUND: Hemorrhagic fever with renal syndrome (HFRS) is an illness caused by hantaviruses. Numerous factors modify the risk of hantavirus transmission. This study explored the epidemiological characteristics, differences, and trends in terms of gender, age, season, and living areas of those diagnosed with domestically acquired HFRS in Taiwan from 2001 to 2019. METHODS: We examined publicly available annual summary data on the domestic cases with HFRS from 2001 to 2019; these data were obtained from the web database of Taiwan's Centers for Disease Control (CDC). RESULTS: This study analyzed 21 domestic cases with HFRS from Taiwan's CDC databases. In this study of the cases of HFRS in Taiwan, a gradual increase in the cases of those aged ≥40 years acquiring the disease was noted, and a distinct pattern of seasonal variation (spring) was observed. Furthermore, more men had domestically acquired HFRS, and living in Taipei metropolitan area (6 cases [28.6%]) and the rural areas (Gao-Ping region, 9 cases [42.9%]) was identified as a potential risk factor. This study represents the first report of confirmed cases of domestically acquired HFRS from surveillance data from Taiwan's CDC, 2001-2019. CONCLUSION: This study highlights the importance of longitudinal studies covering a wide geographical area, particularly for highly fluctuating pathogens, to understanding the implications of the transmission of zoonotic diseases in human populations. Important data were identified to inform future surveillance and research efforts in Taiwan.


Asunto(s)
Fiebre Hemorrágica con Síndrome Renal , Orthohantavirus , Adulto , Anciano , Animales , China , Femenino , Fiebre Hemorrágica con Síndrome Renal/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Taiwán/epidemiología , Adulto Joven , Zoonosis
4.
Biotechnol Bioeng ; 117(6): 1615-1627, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32144753

RESUMEN

The rare ginsenosides are recognized as the functionalized molecules after the oral administration of Panax ginseng and its products. The sources of rare ginsenosides are extremely limited because of low ginsenoside contents in wild plants, hindering their application in functional foods and drugs. We developed an effective combinatorial biotechnology approach including tissue culture, immobilization, and hydrolyzation methods. Rh2 and nine other rare ginsenosides were produced by methyl jasmonate-induced culture of adventitious roots in a 10 L bioreactor associated with enzymatic hydrolysis using six ß-glycosidases and their combination with yields ranging from 5.54 to 32.66 mg L-1 . The yield of Rh2 was furthermore increased by 7% by using immobilized BglPm and Bgp1 in optimized pH and temperature conditions, with the highest yield reaching 51.17 mg L-1 (17.06% of protopanaxadiol-type ginsenosides mixture). Our combinatorial biotechnology method provides a highly efficient approach to acquiring diverse rare ginsenosides, replacing direct extraction from Panax plants, and can also be used to supplement yeast cell factories.


Asunto(s)
Ginsenósidos/metabolismo , Panax/metabolismo , Biotecnología/métodos , Ginsenósidos/química , Hidrólisis , Panax/química , Raíces de Plantas/química , Raíces de Plantas/metabolismo , Técnicas de Cultivo de Tejidos/métodos
5.
Exp Biol Med (Maywood) ; 238(7): 744-54, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23788171

RESUMEN

We previously reported that heat stroke induces autophagy as a protection mechanism against neurodegeneration in the brain. Heme oxygenase (HO)-1 is a stress protein and can be induced by heat stress (HS). Cerebellar Purkinje cells are selectively vulnerable to heat-induced injury. In this study, we first validated an animal model of HS (38°C for 4 h) in which sustained increase of Purkinje cell injury, HO-1 expression up to 24 h post HS (HS24), and hyperthermia reaching a rectal temperature 41.52 ± 0.32 were observed. In subsequent experiments, we investigated the effects of HO-1 on HS-induced Purkinje cell injury. Rats were divided into four groups: one normothermic control group receiving saline vehicle (1 mL/kg, intraperitoneal [i.p.]) and exposed to 25 for 4 h; and three HS groups receiving saline, or HO-1 inducer haemin (30 mg/kg, i.p.) or HO-1 inhibitor tin protoporphyrin (SnPP, 30 mg/kg, i.p.), respectively, at 12 h prior to HS. HS-induced Purkinje cell injury was further enhanced by HO-1 inducer but attenuated by HO-1 inhibitor as evaluated by immunoreactivity of apoptosis marker (active caspase-3) as well as Fluoro-Jade B histochemistry (staining for degenerating neurons), suggesting a detrimental role of HO-1. Interestingly, the protective autophagy was reduced by HO-1 inducer but enhanced by HO-1 inhibitor as demonstrated by autophagy markers including Beclin-1 and microtubule-associated protein light chain 3 in Purkinje cells. Double immunofluorescent labelling of Beclin-1 or 8-hydroxydeoxyguanosine (an oxidative DNA damage marker) with HO-1 immunoreactivity not only demonstrated their co-localization, but also confirmed that HO-1 negatively regulated Beclin-1 but increased oxidative stress in the same Purkinje cell. Taken together, our results indicate that HO-1 aggravates HS injury in cerebellar Purkinje cells. Our findings shed new light on cell damage mechanisms by HS in central nervous system and may help to provide potential therapeutic foci.


Asunto(s)
Autofagia , Respuesta al Choque Térmico , Hemo-Oxigenasa 1/metabolismo , Células de Purkinje/enzimología , Células de Purkinje/patología , 8-Hidroxi-2'-Desoxicoguanosina , Animales , Apoptosis , Proteínas Reguladoras de la Apoptosis/metabolismo , Beclina-1 , Temperatura Corporal , Caspasa 3/metabolismo , Recuento de Células , Deshidratación/complicaciones , Deshidratación/patología , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Regulación hacia Abajo , Hipocampo/enzimología , Hipocampo/patología , Hipertermia Inducida , Masculino , Proteínas Asociadas a Microtúbulos/metabolismo , Degeneración Nerviosa/complicaciones , Degeneración Nerviosa/enzimología , Degeneración Nerviosa/patología , Estrés Oxidativo , Ratas , Ratas Sprague-Dawley , Factores de Tiempo
6.
Shock ; 34(6): 643-8, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20823696

RESUMEN

Heat stroke (HS) is defined clinically as a condition when core body temperature rises above 40°C and is accompanied by central nervous system abnormalities. In this study, we established a rat model of HS by exposing anesthetized rats to elevated ambient temperature (40°C) until core temperature reaching 40.5°C (HS onset). The rat was immediately removed from heating chamber, allowed recovery for various time periods, and killed for histological and biochemical studies. Our results indicated neuronal shrinkage and pyknosis of the nucleus and sustained up to 12 h recovery time in cerebral cortex. Elevated expression of autophagy-related proteins, including microtubule associated protein light chain 3 and beclin 1 in cortical tissue at various times (3, 6, 12 h) of recovery was observed. In addition, the number of autophagosomes stained by monodansylcadaverine, a specific autophagosome marker, increased after heat exposure but was reduced by pretreatment with 3-methyladenine, an autophagy inhibitor. Furthermore, heat exposure increased neuronal degeneration in cortical tissue, as evidenced by staining with the fluorescent dye Fluoro-Jade B for degenerating neuron. Pretreatment with 3-methyladenine in HS rats aggravated neurodegeneration. Taken together, these results suggest that HS induces autophagy as a protection mechanism against neurodegeneration. Modulation of autophagy may provide a potential therapeutic approach for HS and await further research.


Asunto(s)
Autofagia/fisiología , Encéfalo/metabolismo , Golpe de Calor/fisiopatología , Degeneración Nerviosa/prevención & control , Animales , Cadaverina/análogos & derivados , Cadaverina/química , Golpe de Calor/metabolismo , Immunoblotting , Inmunohistoquímica , Degeneración Nerviosa/metabolismo , Fagosomas/metabolismo , Ratas , Ratas Sprague-Dawley
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