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1.
BMJ Case Rep ; 16(1)2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36634987

RESUMEN

Vitamin B12 deficiency is a significant public health problem globally. Although it is a well-known cause of macrocytic anaemia and in advanced cases, pancytopenia, there remains a relative paucity of cases reported in pregnancy. It is associated with an increased risk of pregnancy complications and adverse birth outcomes such as neural tube defects, preterm birth, low birth weight, neurological sequelae and intrauterine death. It has a predilection for individuals aged >60 years. It has been implicated in a spectrum of neuropsychiatric disorders and it may also exert indirect cardiovascular effects. Severe vitamin B12 deficiency may present with haematological abnormalities that mimic thrombotic microangiopathy such as HELLP syndrome (haemolysis, elevated liver enzymes and low platelets) or it may present as pseudothrombotic microangiopathy (Moschcowitz syndrome) characterised by anaemia, thrombocytopenia and schistocytosis. It can also closely mimic thrombotic thrombocytopenia purpura, hence posing a diagnostic challenge to the unwary physician. Serological measurement of vitamin B12 levels confirms the diagnosis. Oral supplementation with vitamin B12 remains a safe and effective treatment. The authors describe the case of a multiparous woman in her late 20s presenting with a plethora of non-specific symptoms at 29+5 weeks' gestation. Her haemoglobin was 45 g/L, platelets 32×109/L, vitamin B12 <150 ng/L and serum folate <2 µg/L. She was not a vegetarian, but her diet lacked nutrition. Following parenteral B12 supplementation, her haematological parameters improved. The pregnancy was carried to term. Due to the plethora of non-specific symptoms, the diagnosis can be challenging to establish. Adverse maternal or fetal outcomes may occur. Folic acid supplementation may mask an occult vitamin B12 deficiency and further exacerbate or initiate neurological disease.


Asunto(s)
Pancitopenia , Complicaciones del Embarazo , Nacimiento Prematuro , Púrpura Trombocitopénica Trombótica , Deficiencia de Vitamina B 12 , Recién Nacido , Embarazo , Femenino , Humanos , Vitamina B 12/uso terapéutico , Pancitopenia/complicaciones , Deficiencia de Vitamina B 12/complicaciones , Deficiencia de Vitamina B 12/diagnóstico , Deficiencia de Vitamina B 12/tratamiento farmacológico , Púrpura Trombocitopénica Trombótica/diagnóstico , Complicaciones del Embarazo/diagnóstico , Vitaminas , Ácido Fólico/uso terapéutico
2.
Oxid Med Cell Longev ; 2022: 5288698, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35237381

RESUMEN

Neurodegenerative diseases, including Alzheimer's disease (AD), Parkinson's disease (PD), and Huntington's disease (HD), are characterized by the progressive degeneration of neurons. Although the etiology and pathogenesis of neurodegenerative diseases have been studied intensively, the mechanism is still in its infancy. In general, most neurodegenerative diseases share common molecular mechanisms, and multiple risks interact and promote the pathologic process of neurogenerative diseases. At present, most of the approved drugs only alleviate the clinical symptoms but fail to cure neurodegenerative diseases. Numerous studies indicate that dietary plant polyphenols are safe and exhibit potent neuroprotective effects in various neurodegenerative diseases. However, low bioavailability is the biggest obstacle for polyphenol that largely limits its adoption from evidence into clinical practice. In this review, we summarized the widely recognized mechanisms associated with neurodegenerative diseases, such as misfolded proteins, mitochondrial dysfunction, oxidative damage, and neuroinflammatory responses. In addition, we summarized the research advances about the neuroprotective effect of the most widely reported dietary plant polyphenols. Moreover, we discussed the current clinical study and application of polyphenols and the factors that result in low bioavailability, such as poor stability and low permeability across the blood-brain barrier (BBB). In the future, the improvement of absorption and stability, modification of structure and formulation, and the combination therapy will provide more opportunities from the laboratory into the clinic for polyphenols. Lastly, we hope that the present review will encourage further researches on natural dietary polyphenols in the treatment of neurodegenerative diseases.


Asunto(s)
Antioxidantes/uso terapéutico , Enfermedades Neurodegenerativas/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Fitoquímicos/uso terapéutico , Fitoterapia/métodos , Extractos Vegetales/uso terapéutico , Polifenoles/uso terapéutico , Animales , Antioxidantes/clasificación , Disponibilidad Biológica , Transporte Biológico , Barrera Hematoencefálica/metabolismo , Modelos Animales de Enfermedad , Humanos , Enfermedades Neurodegenerativas/metabolismo , Fármacos Neuroprotectores/clasificación , Fármacos Neuroprotectores/metabolismo , Estrés Oxidativo/efectos de los fármacos , Fitoquímicos/clasificación , Fitoquímicos/metabolismo , Extractos Vegetales/clasificación , Polifenoles/clasificación , Polifenoles/metabolismo , Resultado del Tratamiento
3.
Open Heart ; 9(1)2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-35086917

RESUMEN

BACKGROUND: Early recognition of ST-segment elevation myocardial infarction (STEMI) is needed for timely cardiac monitoring and reperfusion therapy. METHODS: Three anonymously linked New Zealand national datasets (July 2016-November 2018) were used to assess the utilisation of ambulance transport in STEMI cases, the concordance between ambulance initial clinical impressions and hospital STEMI diagnoses, and the association between initial paramedic clinical impressions and 30-day mortality. The St John Ambulance electronic record captures community call-outs and paramedic initial clinical impressions. The national cardiac (ANZACS-QI) registry and national administrative datasets capture all New Zealand public hospital admission diagnoses and mortality data. RESULTS: Of 5465 patients with STEMI, 73% were transported to hospital by ambulance. For these patients, the initial paramedic impression was STEMI in 50.7%, another acute coronary syndrome (ACS) diagnosis in 19.9% and non-ACS diagnosis in 29.7%. Only 37% of the 5465 patients with STEMI were both transported by ambulance and clinically suspected of STEMI by paramedics. Compared with patients with paramedic-'suspected STEMI', 30-day mortality was over threefold higher for patients thought to have a non-ACS condition (10.9% and 34.9%, respectively), but after adjustment for available covariates, this was substantially ameliorated (HR 1.48, 95% CI 1.22 to 1.80). CONCLUSIONS: In this national data linkage study, only 4 out of every 10 patients with STEMI were both transported by ambulance and had STEMI suspected by paramedics. Although patients with STEMI not suspected of an ACS diagnosis by paramedics had the highest mortality rate, this is largely explained by the different risk profile of these patients.


Asunto(s)
Electrocardiografía/métodos , Servicios Médicos de Urgencia/estadística & datos numéricos , Sistema de Registros , Infarto del Miocardio con Elevación del ST/diagnóstico , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Nueva Zelanda/epidemiología , Estudios Retrospectivos , Infarto del Miocardio con Elevación del ST/mortalidad , Tasa de Supervivencia/tendencias , Factores de Tiempo
4.
BMC Infect Dis ; 21(1): 1156, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34775956

RESUMEN

BACKGROUND: Streptococcus pneumoniae (S. pneumoniae) is a major cause of bacterial meningitis, septicemia and pneumonia in children. Inappropriate choice of antibiotic can have important adverse consequences for both the individual and the community. Here, we focused on penicillin/cefotaxime non-susceptibility of S. pneumoniae and evaluated appropriateness of targeted antibiotic therapy for children with IPD (invasive pneumococcal diseases) in China. METHODS: A multicenter retrospective study was conducted in 14 hospitals from 13 provinces in China. Antibiotics prescription, clinical features and resistance patterns of IPD cases from January 2012 to December 2017 were collected. Appropriateness of targeted antibiotics therapy was assessed. RESULTS: 806 IPD cases were collected. The non-susceptibility rates of S. pneumoniae to penicillin and cefotaxime were 40.9% and 20.7% respectively in 492 non-meningitis cases, whereas those were 73.2% and 43.0% respectively in 314 meningitis cases. Carbapenems were used in 21.3% of non-meningitis cases and 42.0% of meningitis cases for targeted therapy. For 390 non-meningitis cases with isolates susceptible to cefotaxime, vancomycin and linezolid were used in 17.9% and 8.7% of cases respectively for targeted therapy. For 179 meningitis cases with isolates susceptible to cefotaxime, vancomycin and linezolid were prescribed in 55.3% and 15.6% of cases respectively. Overall, inappropriate targeted therapies were identified in 361 (44.8%) of 806 IPD cases, including 232 (28.8%) cases with inappropriate use of carbapenems, 169 (21.0%) cases with inappropriate use of vancomycin and 62 (7.7%) cases with inappropriate use of linezolid. CONCLUSIONS: Antibiotic regimens for IPD definite therapy were often excessive with extensive prescription of carbapenems, vancomycin or linezolid in China. Antimicrobial stewardship programs should be implemented to improve antimicrobial use.


Asunto(s)
Antibacterianos , Infecciones Neumocócicas , Antibacterianos/uso terapéutico , Niño , China/epidemiología , Humanos , Lactante , Pruebas de Sensibilidad Microbiana , Infecciones Neumocócicas/tratamiento farmacológico , Infecciones Neumocócicas/epidemiología , Prescripciones , Estudios Retrospectivos
5.
Hepatol Commun ; 4(8): 1149-1167, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32766475

RESUMEN

It is well known that excessive cholesterol accumulation within hepatocytes deteriorates nonalcoholic fatty liver disease (NAFLD). Augmenter of liver regeneration (ALR) has been reported to alleviate NAFLD through anti-apoptosis; however, whether ALR could protect liver from cholesterol-induced NAFLD remains unclear. Mice with heterozygous deletion of Gfer (the gene for ALR, Gfer +/-) were generated, and liver steatosis was induced by either choline-deficient ethionine-supplemented, methionine choline-deficient diet for 4 weeks, or high-fat diet for 16 weeks. The results showed that Gfer +/- mice developed a more severe fatty liver phenotype than Gfer +/+ mice. The livers of Gfer +/- mice exhibited a higher concentration of cholesterol and low-density lipoprotein compared with the normal mice. Transcriptome-based analysis predicts low-density lipoprotein receptor (LDLR) primarily involved in the metabolic pathway. The experiments further indicate that cholesterol accumulation within hepatocytes is closely associated with enhancing the expression of LDLR and activation of sterol regulatory element binding protein 2 (SREBP2). Because adenosine monophosphate-activated protein kinase (AMPK) is a critical regulator of SREBP2 activation, we measured whether the activity of AMPK was regulated by ALR. We found that knockdown of ALR expression inhibited the phosphorylation of LKB1, an upstream activator of AMPK, followed by AMPK inactivation and SREBP2 maturation/nuclear translocation, leading to extensive cholesterol accumulation. Meanwhile, cellular oxidative stress increased as a result of ALR knockdown, indicating that ALR might also have a role in suppressing reactive oxygen species production. Conclusion: Our results confirm that ALR regulates cholesterol metabolism and alleviates hepatic steatosis probably through the LKB1-AMPK-SREBP2-LDLR pathway in vivo and in vitro, providing a putative mechanism for combating fatty liver disease.

6.
Planta Med ; 86(4): 255-266, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31975362

RESUMEN

Non-alcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases worldwide. Nevertheless, no first-line therapy exists. Hepatic steatosis is the earliest stage of NAFLD, which is characterized by an accumulation of hepatic lipids. Patchouli oil (PO), which is isolated from the well-known Chinese herb named Pogostemon cablin (Blanco) Benth. (Lamiaceae), inhibits hepatic lipid accumulation effectively. However, its potential ability for the treatment of NAFLD had not been reported before. Thus, the objective of this study was to investigate the effectiveness of PO against hepatic steatosis and its underlying mechanisms. We used a high fat diet (HFD)-induced hepatic steatosis model of rats to estimate the effect of PO against NAFLD. Hematoxylin-eosin and oil red O staining were used to analyze the hepatic histopathological changes. ELISA, RT-qPCR, and Western blotting analysis were applied to evaluate the parameters for hepatic steatosis. Our results showed that PO significantly attenuated the lipid profiles and the serum enzymes, evidenced by quantitative and histopathological analyses. It also markedly down-regulated the expression of sterol regulatory element-binding protein 1 (SREPB-1c) with its downstream factors in de novo lipogenesis. And, likewise, in lipid export by very low-density lipoproteins (VLDL), related molecules were dramatically improved. Furthermore, PO observably normalized the aberrant peroxisome proliferator-activated receptor α (PPAR-α) signal in fatty acids oxidation. In conclusion, PO exerted a preventing effect against HFD-induced steatosis and might be due to decrease de novo lipogenesis, promote export of lipids, as well as owing to improve fatty acids oxidation.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Animales , Dieta Alta en Grasa , Lipogénesis , Hígado , Pogostemon , Ratas
7.
Cell Physiol Biochem ; 51(1): 154-172, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30439703

RESUMEN

BACKGROUND/AIMS: It has been implicated that calcium supplementation is involved in reducing body weight/fat and improving glucose homeostasis. However, the underlying mechanisms are still not fully understood. Here, we investigated the effects of calcium supplementation on adipogenesis and glucose homeostasis in porcine bone marrow mesenchymal stem cells (pBMSCs) and high fat diet (HFD)-fed mice and explored the involved signaling pathways. METHODS: In vitro, pBMSCs were treated with 4 mM extracellular calcium ([Ca2+]o) and/or 1 µM nifedipine, 0.1 µM BAPTA-AM, 1 µM KN-93, 50 nM wortmannin for 10 days. The intracellular calcium ([Ca2+]i) levels were measured using Fluo 3-AM by flow cytometry. The adipogenic differentiation of pBMSCs was determined by Oil Red-O staining and triglyceride assay. The expression of marker genes involved in adipogenesis (peroxisome proliferator activated receptor γ (PPARγ) and CCAAT/enhancer binding protein α (C/EBPα)) and glucose uptake (glucose transporter 4 (GLUT4)), as well as the activation of Ca2+/calmodulin-dependent protein kinase II (CaMKII) and PI3K/Akt-FoxO1/AS160 signaling pathways were determined by Western blotting. Glucose uptake and utilization were examined using 2-NBDG assay and glucose content assay, respectively. In vivo, C57BL/6J male mice were fed a HFD (containing 1.2% calcium) without or with 0.6% (w/w) calcium chloride in drinking water for 13 weeks. The adipogenesis, glucose homeostasis and the involvement of CaMKII and PI3K/Akt signaling pathway were also assessed. RESULTS: In vitro, [Ca2+]o stimulated pBMSCs adipogenesis by increasing [Ca2+]i level and activating CaMKII and PI3K/Akt-FoxO1 pathways. In addition, [Ca2+]o promoted glucose uptake/utilization by enhancing AS160 phosphorylation, GLUT4 expression and translocation. However, the stimulating effects of [Ca2+]o on pBMSCs adipogenesis and glucose uptake/utilization were abolished by L-VGCC blocker Nifedipine, [Ca2+]i chelator BAPTA-AM, CaMKII inhibitor KN-93, or PI3K inhibitor Wortmannin. In vivo, calcium supplementation decreased body weight and fat content, increased adipocyte number, and improved glucose homeostasis, with elevated PPARγ and GLUT4 expression and PI3K/Akt activation in iWAT. CONCLUSION: calcium supplementation enhanced adipogenesis and glucose uptake in pBMSCs, which was coincident with the increased adipocyte number and improved glucose homeostasis in HFD-fed mice, and was associated with activation of CaMKII and PI3K/Akt-FoxO1/AS160 pathways. These data provided a broader understanding of the mechanisms underlying calcium-induced body weight/fat loss and glycemic control.


Asunto(s)
Adipogénesis/efectos de los fármacos , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Calcio/farmacología , Glucosa/metabolismo , Transducción de Señal/efectos de los fármacos , Animales , Células de la Médula Ósea/citología , Canales de Calcio Tipo L/química , Canales de Calcio Tipo L/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/antagonistas & inhibidores , Diferenciación Celular/efectos de los fármacos , Dieta Alta en Grasa , Transportador de Glucosa de Tipo 4/metabolismo , Masculino , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Endogámicos C57BL , PPAR gamma/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Proteínas Proto-Oncogénicas c-akt/metabolismo , Porcinos , Wortmanina/farmacología
8.
Food Funct ; 9(4): 2043-2050, 2018 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-29570193

RESUMEN

Stimulating the browning of white adipocytes contributes to the restriction of obesity and related metabolic disorders. This study aimed to investigate the browning effects of phytol on mice inguinal subcutaneous white adipose tissue (iWAT) and explore the underlying mechanisms. Our results demonstrated that phytol administration decreased body weight gain and iWAT index, and stimulated the browning of mice iWAT, with the increased expression of brown adipocyte marker genes (UCP1, PRDM16, PGC1α, PDH, and Cyto C). In addition, phytol treatment activated the AMPKα signaling pathway in mice iWAT. In good agreement with the in vivo findings, the in vitro results showed that 100 µM phytol stimulated brown adipogenic differentiation and formation of brown-like adipocytes in the differentiated 3T3-L1 by increasing the mitochondria content and oxygen consumption, and promoting mRNA and/or protein expression of brown adipocyte markers (UCP1, PRDM16, PGC1α, PDH, Cyto C, Cidea and Elovl3) and beige adipocyte markers (CD137 and TMEM26). Meanwhile, phytol activated the AMPKα signaling pathway in the differentiated 3T3-L1. However, the inhibition of AMPKα with Compound C totally abolished phytol-stimulated brown adipogenic differentiation and formation of brown-like adipocytes. In conclusion, these results showed that phytol stimulated the browning of mice iWAT, which was coincident with the increased formation of brown-like adipocytes in the differentiated 3T3-L1, and appeared to be primarily mediated by the AMPKα signaling pathway. These data provided new insight into the role of phytol in regulating the browning of WAT and suggested the potential application of phytol as a nutritional intervention for the restriction of obesity and related metabolic disorders.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Adipocitos Beige/metabolismo , Fármacos Antiobesidad/uso terapéutico , Suplementos Dietéticos , Obesidad/prevención & control , Fitol/uso terapéutico , Grasa Subcutánea Abdominal/metabolismo , Células 3T3-L1 , Proteínas Quinasas Activadas por AMP/antagonistas & inhibidores , Proteínas Quinasas Activadas por AMP/química , Adipocitos Beige/efectos de los fármacos , Adipocitos Beige/patología , Adipogénesis/efectos de los fármacos , Adiposidad , Animales , Fármacos Antiobesidad/antagonistas & inhibidores , Fármacos Antiobesidad/metabolismo , Biomarcadores/metabolismo , Dieta Alta en Grasa/efectos adversos , Activación Enzimática/efectos de los fármacos , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Metabolismo de los Lípidos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Obesidad/etiología , Obesidad/metabolismo , Obesidad/patología , Fitol/antagonistas & inhibidores , Fitol/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Distribución Aleatoria , Transducción de Señal/efectos de los fármacos , Grasa Subcutánea Abdominal/efectos de los fármacos , Grasa Subcutánea Abdominal/patología
9.
J Pineal Res ; 63(2)2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28480587

RESUMEN

Prolonged exposure to gamma-hydroxybutyric acid (GHB) would cause drug intoxication in which impaired cognitive function results from enhanced hippocampal oxidative stress may serve as a major symptom in this deficiency. Considering melatonin possesses significant anti-oxidative efficacy, this study aimed to determine whether melatonin would successfully promote the nuclear factor erythroid 2-related factor 2 and antioxidant responsive element (Nrf2-ARE) signaling, depress oxidative stress, and rescue hippocampal bioenergetics and cognitive function following drug intoxication injury. Adolescent rats subjected to 10 days of GHB were received melatonin at doses of either 10 or 100 mg/kg. Time-of-flight secondary ion mass spectrometry, biochemical assay, quantitative histochemistry, [14 C]-2-deoxyglucose analysis, together with Morris water maze were employed to detect the molecular signaling, oxidative status, bioenergetic level, as well as the cognitive performances, respectively. Results indicated that in GHB-intoxicated rats, enhanced oxidative stress, increased cholesterol level, and decreased anti-oxidative enzymes activities were detected in hippocampal regions. Intense oxidative stress paralleled well with reduced bioenergetics and poor performance in behavioral testing. However, in rats treated with melatonin following GHB intoxication, all above parameters and cognitive function were gradually returned to nearly normal levels. Melatonin also remarkably promoted the translocation of Nrf2 from cytoplasm to nucleus in a dose-dependent manner, thereby increased the Nrf2-ARE signaling-related downstream anti-oxidative enzymes activities. As melatonin effectively rescues hippocampal bioenergetics through depressing the oxidative stress by promoting Nrf2-ARE molecular machinery, this study thus highlights for the first time that clinical use of melatonin may serve as a therapeutic strategy to improve the cognitive function in unsuspecting victims suffered from GHB intoxication injury.


Asunto(s)
Elementos de Respuesta Antioxidante , Cognición/efectos de los fármacos , Hipocampo , Melatonina/farmacología , Factor 2 Relacionado con NF-E2/metabolismo , Oxibato de Sodio/efectos adversos , Animales , Conducta Animal/efectos de los fármacos , Hipocampo/metabolismo , Hipocampo/patología , Hipocampo/fisiopatología , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Wistar , Oxibato de Sodio/farmacología
10.
Bioresour Technol ; 216: 478-85, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27268432

RESUMEN

An air-cathode MFC-adsorption hybrid system, made from earthen pot was designed and tested for simultaneous wastewater treatment and energy recovery. Such design had demonstrated superior characteristics of low internal resistance (29.3Ω) and favor to low-cost, efficient wastewater treatment and power generation (55mW/m(3)) with average current of 2.13±0.4mA. The performance between MFC-adsorption hybrid system was compared to the standalone adsorption system and results had demonstrated great pollutants removals of the integrated system especially for chemical oxygen demand (COD), biochemical oxygen demand (BOD3), total organic carbon (TOC), total volatile solids (TVS), ammoniacal nitrogen (NH3-N) and total nitrogen (TN) because such system combines the advantages of each individual unit. Besides the typical biological and electrochemical processes that happened in an MFC system, an additional physicochemical process from the activated carbon took place simultaneously in the MFC-adsorption hybrid system which would further improved on the wastewater quality.


Asunto(s)
Fuentes de Energía Bioeléctrica , Aceites de Plantas/química , Aguas Residuales/química , Purificación del Agua/métodos , Adsorción , Análisis de la Demanda Biológica de Oxígeno , Carbono/química , Electrodos , Nitrógeno , Aceite de Palma , Aguas Residuales/análisis
11.
Food Chem ; 197 Pt B: 1121-9, 2016 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-26675848

RESUMEN

Fucoidan, a multifunctional marine polymer, is normally extracted from brown algae via extensive use of acid, solvent or high temperature water and a long reaction time. In present study, we developed a novel compressional-puffing-hydrothermal extraction (CPHE) process which primarily decomposes the cellular structure of algae and facilitates the release of fucoidan by hot water extraction. The CPHE process provides a number of advantages including simple procedure, reactant-saving, reduced pollution, and feasibility for continuous production. Sargassum glaucescens (SG) was utilized in this study, and the maximum extraction yield of polysaccharide was approximately 9.83 ± 0.11% (SG4). Thin layer chromatography (TLC), Fourier transform infrared (FTIR) analysis, and measurements of monosaccharide composition, fucose, sulfate, and uronic acid contents revealed that the extracted polysaccharide showed characteristics of fucoidan. All extracts exhibited antioxidant activities, and thus, further exploration of these extracts as potential natural and safe antioxidant agents is warranted.


Asunto(s)
Antioxidantes/farmacología , Extractos Vegetales/farmacología , Polisacáridos/aislamiento & purificación , Sargassum , Polisacáridos/farmacología , Sargassum/química
12.
J Nutr Biochem ; 22(4): 351-9, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20655717

RESUMEN

Monocytes expressing toll-like receptor 4 (TLR4) play a major role in regulating the innate immune response and are involved in systemic inflammation. Previous studies have shown that Ginkgo biloba extract (GBE) may act as a therapeutic agent for some cardiovascular and neurological disorders. The objective of this study was to determine whether GBE could modulate immunity in human cells. The monocytic cell line THP-1 was used. Enzyme-linked immunosorbent assay results showed that lipopolysaccharide (LPS) induces the expression of monocyte chemotactic protein-1 (MIP-1), tumor necrosis factor-α, stromal cell-derived factor-1, and MIP-1α, and this induction may be repressed by GBE treatment due to TLR4 blockade. The Griess reagent assay and western blot analysis showed that GBE-mediated inhibition of TLR4 expression was associated with the activation of mitogen-activated protein kinase and production of nitric oxide (NO). Actinomycin D chase experiments demonstrated that GBE decreased the TLR4 mRNA stability in cells. Confocal microscopy and real-time polymerase chain reaction showed that GBE induced the expression of intracellular tristetraprolin (TTP). Transfection with TTP siRNA reversed the effects of GBE in naïve or TLR4-overexpressing cells. Treatment with SNAP (an NO donor) may increase intracellular TTP expression in cells. Immunoprecipitation analysis showed that GBE mediates TTP activation and increases the interaction of TTP with the 3' untranslated region (UTR) of TLR4 mRNA by regulating NO production. Our findings indicate that GBE could decrease the sensitivity of monocytes to LPS. Utilizing TTP to control TLR4 expression may be a promising approach for controlling systemic inflammation, and GBE may have potential applications in the clinical treatment of immune diseases.


Asunto(s)
Ginkgo biloba/química , Monocitos/efectos de los fármacos , Extractos Vegetales/farmacología , Receptor Toll-Like 4/biosíntesis , Línea Celular , Dactinomicina/farmacología , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Quinasas MAP Reguladas por Señal Extracelular/fisiología , Humanos , Lipopolisacáridos , Monocitos/metabolismo , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/farmacología , S-Nitroso-N-Acetilpenicilamina/farmacología , Tristetraprolina/antagonistas & inhibidores , Tristetraprolina/farmacología
13.
J Agric Food Chem ; 58(24): 12941-9, 2010 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-21070071

RESUMEN

Ursolic acid (UA), a triterpenoid compound found in plants, is used in the human diet and in medicinal herbs and possesses a wide range of biological benefits including antioxidative, anti-inflammatory, and anticarcinogenic effects. Endothelial expression of allograft inflammatory factor-1 (AIF-1) mediates vasculogenesis, and nitric oxide (NO) produced by endothelial NO (eNOS) represents a mechanism of vascular protection. It is unclear whether UA affects the neovascularization mediated by AIF-1 and eNOS expression. This study investigated the effects and mechanisms of UA on angiogenesis in vivo in hind limb ischemic animal models and in vitro in human coronary artery endothelial cells (HCECs). This study explored the impact of UA on endothelial cell (EC) activities in vitro in HCECs, vascular neovasculogenesis in vivo in a mouse hind limb ischemia model, and the possible role of AIF-1 in vasculogenesis. The results demonstrate that UA enhances collateral blood flow recovery through induction of neovascularization in a hind limb ischemia mouse model. In vitro data showed that UA increases tube formation and migration capacities in human endothelial cells, and exposing HCECs to UA increased AIF-1 expression through a NO-related mechanism. Moreover, UA administration increased capillary density and eNOS and AIF-1 expression in ischemic muscle. These findings suggest that UA may be a potential therapeutic agent in the induction of neovascularization and provide a novel mechanistic insight into the potential effects of UA on ischemic vascular diseases.


Asunto(s)
Inductores de la Angiogénesis/administración & dosificación , Proteínas de Unión al Calcio/genética , Isquemia/tratamiento farmacológico , Óxido Nítrico/metabolismo , Triterpenos/administración & dosificación , Animales , Proteínas de Unión al Calcio/metabolismo , Línea Celular , Modelos Animales de Enfermedad , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Expresión Génica/efectos de los fármacos , Miembro Posterior/irrigación sanguínea , Miembro Posterior/efectos de los fármacos , Miembro Posterior/metabolismo , Miembro Posterior/patología , Humanos , Isquemia/genética , Isquemia/metabolismo , Isquemia/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Proteínas de Microfilamentos , Neovascularización Patológica , Óxido Nítrico Sintasa de Tipo III/genética , Óxido Nítrico Sintasa de Tipo III/metabolismo , Ácido Ursólico
14.
Proc Natl Acad Sci U S A ; 107(37): 16372-7, 2010 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-20805495

RESUMEN

Gonadotropin-releasing hormone (GnRH) signaling regulates reproductive physiology in mammals. GnRH is released by a subset of hypothalamic neurons and binds to GnRH receptor (GnRHR) on gonadotropes in the anterior pituitary gland to control production and secretion of gonadotropins that in turn regulate the activity of the gonads. Central control of reproduction is well understood in adult animals, but GnRH signaling has also been implicated in the development of the reproductive axis. To investigate the role of GnRH signaling during development, we selectively ablated GnRHR-expressing cells in mice. This genetic strategy permitted us to identify an essential stage in male reproductive axis development, which depends on embryonic GnRH signaling. Our experiments revealed a striking dichotomy in the gonadotrope population of the fetal anterior pituitary gland. We show that luteinizing hormone-expressing gonadotropes, but not follicle-stimulating hormone-expressing gonadotropes, express the GnRHR at embryonic day 16.75. Furthermore, we demonstrate that an embryonic increase in luteinizing hormone secretion is needed to promote development of follicle-stimulating hormone-expressing gonadotropes, which might be mediated by paracrine interactions within the pituitary. Moreover, migration of GnRH neurons into the hypothalamus appeared normal with appropriate axonal connections to the median eminence, providing genetic evidence against autocrine regulation of GnRH neurons. Surprisingly, genetic ablation of GnRHR expressing cells significantly increased the number of GnRH neurons in the anterior hypothalamus, suggesting an unexpected role of GnRH signaling in establishing the size of the GnRH neuronal population. Our experiments define a functional role of embryonic GnRH signaling.


Asunto(s)
Hormona Liberadora de Gonadotropina/metabolismo , Maduración Sexual , Transducción de Señal , Animales , Células Cultivadas , Femenino , Regulación del Desarrollo de la Expresión Génica , Hipogonadismo/genética , Hipogonadismo/metabolismo , Hipotálamo/metabolismo , Masculino , Ratones , Ratones Transgénicos , Adenohipófisis/embriología , Adenohipófisis/metabolismo , Receptores LHRH/genética , Receptores LHRH/metabolismo
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