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1.
J Chin Med Assoc ; 87(2): 139-141, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38305483

RESUMEN

The coronavirus disease 2019 (COVID-19) pandemic has had a major impact on human life. This review highlights the versatile roles of both classical and modern structure-based approaches for COVID-19. X-ray crystallography, nuclear magnetic resonance spectroscopy, and cryogenic electron microscopy are the three cornerstones of classical structural biology. These technologies have helped provide fundamental and detailed knowledge regarding severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the related human host proteins as well as enabled the identification of its target sites, facilitating the cessation of its transmission. Further progress into protein structure modeling was made using modern structure-based approaches derived from homology modeling and integrated with artificial intelligence (AI), facilitating advanced computational simulation tools to actively guide the design of new vaccines and the development of anti-SARS-CoV-2 drugs. This review presents the practical contributions and future directions of structure-based approaches for COVID-19.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Inteligencia Artificial , Vacunas contra la COVID-19 , Simulación por Computador
2.
J Chin Med Assoc ; 86(2): 135-137, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36524941

RESUMEN

The Omicron variant BA.2 is the dominant form of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak in many countries, including those that have already implemented the strictest quarantine mandates that effectively contained the spread of the previous variants. Although many individuals were partially or fully vaccinated, confirmed Omicron infections have far surpassed all other variants combined in just a couple of months since the Omicron variant emerged. The ChAdOx1-S (AstraZeneca), BNT162b2 (Pfizer-BioNTech), and mRNA-1273 (Moderna) vaccines offer protection against the severe illness of SARS-CoV-2 infection; however, these currently available vaccines are less effective in terms of preventing Omicron infections. As a result, a booster dose of BNT162b2 or mRNA-1273 is recommended for individuals >12 years old who had received their second dose of the approved vaccines for >5 months. Herein, we review the studies that assessed the clinical benefits of the booster dose of vaccines against Omicron infections. We also analyzed public data to address whether early booster vaccination effectively prevented the surge of the Omicron infections. Finally, we discuss the consideration of a fourth dose of vaccine as a way to prevent possible upcoming infections.


Asunto(s)
Vacuna nCoV-2019 mRNA-1273 , COVID-19 , Humanos , Niño , Vacuna BNT162 , COVID-19/prevención & control , SARS-CoV-2
3.
J Chin Med Assoc ; 86(2): 138-146, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36227021

RESUMEN

COVID-19 has greatly affected human life for over 3 years. In this review, we focus on smart healthcare solutions that address major requirements for coping with the COVID-19 pandemic, including (1) the continuous monitoring of severe acute respiratory syndrome coronavirus 2, (2) patient stratification with distinct short-term outcomes (eg, mild or severe diseases) and long-term outcomes (eg, long COVID), and (3) adherence to medication and treatments for patients with COVID-19. Smart healthcare often utilizes medical artificial intelligence (AI) and cloud computing and integrates cutting-edge biological and optoelectronic techniques. These are valuable technologies for addressing the unmet needs in the management of COVID. By leveraging deep learning/machine learning capabilities and big data, medical AI can perform precise prognosis predictions and provide reliable suggestions for physicians' decision-making. Through the assistance of the Internet of Medical Things, which encompasses wearable devices, smartphone apps, internet-based drug delivery systems, and telemedicine technologies, the status of mild cases can be continuously monitored and medications provided at home without the need for hospital care. In cases that develop into severe cases, emergency feedback can be provided through the hospital for rapid treatment. Smart healthcare can possibly prevent the development of severe COVID-19 cases and therefore lower the burden on intensive care units.


Asunto(s)
COVID-19 , Humanos , Inteligencia Artificial , Síndrome Post Agudo de COVID-19 , Pandemias/prevención & control , Atención a la Salud
4.
Ann Hematol ; 91(1): 93-102, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21584671

RESUMEN

The applicability of the International Staging System (ISS) for Chinese patients with multiple myeloma (MM) has not been demonstrated, especially with respect to treatments with novel agents. Newly diagnosed MM patients at Taipei Veterans General Hospital were enrolled between 1996 and 2007. Data regarding clinical features, laboratory tests, and outcome at last follow-up were collected. A total of 389 MM patients (71% male) were enrolled, with median age of 71 years. At diagnosis, 72.7% had Durie-Salmon (DS) stage III disease, 56.2% had ISS stage III disease, and 34% had serum creatinine ≧2.0 mg/dL. Compared with patients diagnosed in the first calendar period 1996-2001, the patients of the second calendar period 2002-2007 were older and more of these patients had received novel agents, especially thalidomide. The median overall survival period was 20.5 months, with a significant increase of patients in the second calendar period (15.3 and 28.2 months, respectively; P = 0.002), especially for those with ISS stages I and II. In the Cox proportion model, elevated serum ß(2) microglobulin at diagnosis (≧3.5 mg/L), old age (≧65 years), and impaired renal function were found to be independently associated with poor survival. Over the entire period, the ISS was found to be effective in providing an accurate prognosis with respect to different ages and calendar periods. This is the first study to show the applicability of ISS for Chinese patients with MM, especially for those who had received thalidomide.


Asunto(s)
Antineoplásicos/uso terapéutico , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/patología , Pronóstico , Adulto , Anciano , Anciano de 80 o más Años , Pueblo Asiatico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Tasa de Supervivencia , Talidomida/uso terapéutico
5.
J Chin Med Assoc ; 85(9): 891-895, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35816282

RESUMEN

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its variants of concern can infect people of all ages and can cause severe diseases in children, such as encephalitis, which require intensive care. Therefore, vaccines are urgently required to prevent severe disease in all age groups. We reviewed the safety and efficacy profiles of mRNA vaccines-BNT162b2 and mRNA-1273-demonstrated by clinical trials or observed in the real world. mRNA-1273 is effective in preventing SARS-CoV-2 infection in preschool children (6 months-6 years old). Both BNT162b2 and mRNA-1273 are effective in preventing SARS-CoV-2 infection in school-aged children and adolescents, thereby preventing post-coronavirus disease (COVID) conditions. The common side effects of vaccination are pain at the injection site, fatigue, and headache. Myocarditis and pericarditis are uncommon. Monitoring post-vaccination troponin levels may help prevent severe cardiac events. The SARS-CoV-2 coronavirus mutates its genome to overcome the herd immunity provided by mass vaccinations; therefore, we may need to develop new generations of vaccines, such as those using viral nucleocapsid proteins as antigens. In conclusion, the mRNA vaccines are generally safe and effective in preventing severe diseases and hospitalization among children and adolescents.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Adolescente , Vacuna BNT162 , COVID-19/prevención & control , Vacunas contra la COVID-19/efectos adversos , Niño , Preescolar , Hospitalización , Humanos , Proteínas de la Nucleocápside , SARS-CoV-2 , Troponina , Vacunación , Vacunas Virales
6.
J Chin Med Assoc ; 84(8): 745-753, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34225337

RESUMEN

The detrimental impact of the heavy metal lead (Pb) on human health has been studied for years. The fact that Pb impairs human body has been established from countless painful and sad historical events. Nowadays, World Health Organization and many developmental countries have established regulations concerning the use of Pb. Measuring the blood lead level (BLL) is so far the only way to officially evaluate the degree of Pb exposure, but the so-called safety value (10 µg/dL in adults and 5 µg/dL in children) seems unreliable to represent the security checkpoint for children through daily intake of drinking water or physical contact with a lower contaminated level of Pb contents. In general, unsolved mysteries about the Pb toxicological mechanisms still remain. In this review article, we report on the methods to prevent Pb poison for further Pb toxicological research. We establish high-sensitivity Pb monitoring, and also report on the use of fluorescent biosensors such as genetically-encoded fluorescence resonance energy transfer-based biosensors built for various large demands such as the detection of severe acute respiratory syndrome coronavirus 2. We also contribute to the development and optimization of the FRET-based Pb biosensors. Our well-performed version of Met-lead 1.44 M1 has achieved a limit of detection of 10 nM (2 ppb; 0.2 µg/dL) and almost 5-fold in dynamic range (DR) supported for the real practical applications-that is, the in-cell Pb sensing device for blood and blood-related samples, and the Pb environmental detections in vitro. The perspective of our powerful Pb biosensor incorporated with a highly sensitive bio-chip of the portable device for quick Pb measurements will be addressed for further manipulation.


Asunto(s)
Técnicas Biosensibles/métodos , Transferencia Resonante de Energía de Fluorescencia/métodos , Plomo/análisis , Ambiente
7.
J Chin Med Assoc ; 84(5): 478-484, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33883466

RESUMEN

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues the pandemic spread of the coronavirus disease 2019 (COVID-19), over 60 million people confirmed infected and at least 1.8 million dead. One of the most known features of this RNA virus is its easiness to be mutated. In late 2020, almost no region of this SARS-CoV-2 genome can be found completely conserved within the original Wuhan coronavirus. Any information of the SARS-CoV-2 variants emerged through as time being will be evaluated for diagnosis, treatment, and prevention of COVID-19. METHODS: We extracted more than two million data of SARS-CoV-2 infected patients from the open COVID-19 dashboard. The sequences of the 38-amino acid putative open reading frame 10 (Orf10) protein within infected patients were gathered output through from National Center for Biotechnology Information and the mutation rates in each position were analyzed and presented in each month of 2020. The mutation rates of A8 and V30 within Orf10 are displayed in selected counties: United States, India, German, and Japan. RESULTS: The numbers of COVID-19 patients are correlated to the death numbers, but not with the death rates (stable and <3%). The amino acid positions locating at A8(F/G/L), I13, and V30(L) within the Orf10 sequence stay the highest mutation rate; N5, N25, and N36 rank at the lowest one. A8F expressed highly dominant in Japan (over 80%) and German (around 40%) coming to the end of 2020, but no significant finding in other countries. CONCLUSION: The results demonstrate via mutation analysis of Orf10 can be further combined with advanced tools such as molecular simulation, artificial intelligence, and biosensors that can practically revealed for protein interactions and thus to imply the authentic Orf10 function of SARS-CoV-2 in the future.


Asunto(s)
COVID-19/mortalidad , Mutación , Sistemas de Lectura Abierta/genética , SARS-CoV-2/genética , COVID-19/virología , Humanos , Sistemas de Lectura Abierta/fisiología
8.
J Chin Med Assoc ; 84(3): 245-247, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33433137

RESUMEN

The rapid spread of coronavirus disease (COVID-19) in many countries has caused inconvenience in conducting daily life activities, and even deaths. Dexamethasone is a corticosteroid applied in clinical medicine since 1957, especially in immune therapy fields. Herein, we present the characteristics of Dexamethasone, from molecular mechanisms such as genomic and nongenomic pathways by cellular signal regulations, to clinical applications in various phases of the disease. During COVID-19 pandemic, Dexamethasone given to patients who required oxygen or ventilation therapy showed improved life efficacy.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Dexametasona/farmacología , SARS-CoV-2 , Dexametasona/uso terapéutico , Humanos , Receptores de Glucocorticoides/fisiología , Transducción de Señal/fisiología
9.
J Chin Med Assoc ; 84(12): 1100-1108, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34596084

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) ranks many tasks in clinical oncology due to possibly developing a general tumor in men and, usually lead to malignant to death within years. Researches had reported about major factors for being HCC was male sex and HCC associated with cirrhosis in childhood was found more common in males than females. In certain mouse strains as studied, breeding with testosterone significantly increases the development of HCC. Furthermore, castration of male mice diminished the frequency of the development of liver tumors. Meanwhile male hepatitis B virus transgenic mice have a greater occurrence of HCC than females. METHODS: We apply degenerate priming PCR to observe the expression of various steroid receptors in livers. Yeast-two hybrid screening to search a novel RNA fragment helps to find a new full-length gene by RACE experiment. RT-PCR is applied to detect various expressions in tissues and cell lines. In situ hybridization detects DNA in Chromosome mapping. GFP-constructs transfection proves the gene localization in cells. Immunoprecipitation pulldown assay verifies protein interaction. Gene transfection followed with luciferase assay demonstrates the interaction of genes within cellular signaling. Genomic alignment analysis for observing sequences data perform from NCBI database website (http://www.ncbi.nim.nih.gov/genebank/). RESULTS: The androgen receptor (AR) expression level is found at the highest level among the steroid receptors families detected in liver tumors. By yeast-two hybrid screening, we cloned an Androgen Receptor Complex Associated Protein (ARCAP), of 95 Kd in molecular weight and its cDNA. ARCAP locates at Chromosome 1. Our findings indicate ARCAP is highly expressed in hepatoma cell lines and liver tumors and their adjacent tumors as observed. Yeast two-hybrid assay and in vitro immunoprecipitation assays demonstrated an interaction between AR and ARCAP. CONCLUSION: We aim to search for different types and levels of steroid receptors expressed within human HCCs and in the adjacent liver tissues. To verify possible molecular mechanisms by which AR might affect hepatoma cells, we had characterized a novel protein ARCAP which functions as a coregulator to interact with AR within liver. The ligand-dependent AR with its cofactor, ARCAP, can induce a signal cascade by transactivation.


Asunto(s)
Carcinoma Hepatocelular/fisiopatología , Neoplasias Hepáticas , Hígado/metabolismo , Hígado/fisiopatología , Receptores Androgénicos/metabolismo , Animales , Virus de la Hepatitis B , Masculino , Ratones , Receptores Androgénicos/genética
10.
J Chin Med Assoc ; 83(8): 701-703, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32349033

RESUMEN

The recent outbreak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has been causing respiratory diseases globally, damaging wide ranges of social-economic activities. This virus is transmitted through personal contact and possibly also through ambient air. Effective biosensor platforms for the detection of this virus and the related host response are in urgent demand. These platforms can facilitate routine diagnostic assays in certified clinical laboratories. They can also be integrated into point-of-care products. Furthermore, environmental biosensors can be designed to detect SARS-CoV-2 in the ambient air or in the intensive care ventilators. Here, we evaluate technical components of biosensors, including the biological targets of recognition, the recognition methods, and the signal amplification and transduction systems. Effective SARS-CoV-2 detectors can be designed by an adequate combination of these technologies.


Asunto(s)
Betacoronavirus/aislamiento & purificación , Técnicas Biosensibles/métodos , Infecciones por Coronavirus/diagnóstico , Neumonía Viral/diagnóstico , COVID-19 , Transferencia Resonante de Energía de Fluorescencia , Humanos , Pandemias , SARS-CoV-2
11.
J Chin Med Assoc ; 83(6): 524-526, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32502116

RESUMEN

The rapid spread of coronavirus disease 2019 (COVID-19) in many countries causes citizens of daily inconvenience and even life-threat for elderly population. The invasion of the main pathogen, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2; 2019 novel coronavirus [2019-nCoV]), into human body causes different levels of impact to various patients. One of the most important issues for COVID-19 is how to defend this virus with the ability to foresee the infected targets. Thus, we maintain the quarantined essentially as for as others saved from COVID-19. So far, the routine laboratory test to confirm whether infected by SARS-CoV-2/2019-nCoV or not is through real-time reverse transcription polymerase chain reaction (rRT-PCR; quantitative polymerase chain reaction [qPCR]) with certain sequence regions that recognize SARS-CoV-2/2019-nCoV RNA genome. The heavy loading of rRT-PCR (qPCR) machine and handling labor have tight-packed the instruments as well as the manpower almost in every country. Therefore, the alternative approaches are eagerly waiting to be developed. In this review article, we sort out some state-of-the-art novel approaches that might be applied for a fast, sensitive, and precise detection of SARS-CoV-2/2019-nCoV not only to help the routine laboratory testing but also to improve effective quarantine.


Asunto(s)
Betacoronavirus/aislamiento & purificación , Infecciones por Coronavirus/diagnóstico , Neumonía Viral/diagnóstico , COVID-19 , Técnicas de Laboratorio Clínico , Humanos , Pandemias , ARN Viral/análisis , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , SARS-CoV-2
12.
J Chin Med Assoc ; 83(8): 725-732, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32773643

RESUMEN

BACKGROUND: The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused severe pneumonia at December 2019. Since then, it has been wildly spread from Wuhan, China, to Asia, European, and United States to become the pandemic worldwide. Now coronavirus disease 2019 were globally diagnosed over 3 084 740 cases with mortality of 212 561 toll. Current reports variants are found in SARS-CoV-2, majoring in functional ribonucleic acid (RNA) to transcribe into structural proteins as transmembrane spike (S) glycoprotein and the nucleocapsid (N) protein holds the virus RNA genome; the envelope (E) and membrane (M) alone with spike protein form viral envelope. The nonstructural RNA genome includes ORF1ab, ORF3, ORF6, 7a, 8, and ORF10 with highly conserved information for genome synthesis and replication in ORF1ab. METHODS: We apply genomic alignment analysis to observe SARS-CoV-2 sequences from GenBank (http://www.ncbi.nim.nih.gov/genebank/): MN 908947 (China, C1); MN985325 (United States: WA, UW); MN996527 (China, C2); MT007544 (Australia: Victoria, A1); MT027064 (United States: CA, UC); MT039890 (South Korea, K1); MT066175 (Taiwan, T1); MT066176 (Taiwan, T2); LC528232 (Japan, J1); and LC528233 (Japan, J2) and Global Initiative on Sharing All Influenza Data database (https://www.gisaid.org). We adopt Multiple Sequence Alignments web from Clustalw (https://www.genome.jp/tools-bin/clustalw) and Geneious web (https://www.geneious.com. RESULTS: We analyze database by genome alignment search for nonstructural ORFs and structural E, M, N, and S proteins. Mutations in ORF1ab, ORF3, and ORF6 are observed; specific variants in spike region are detected. CONCLUSION: We perform genomic analysis and comparative multiple sequence of SARS-CoV-2. Large scaling sequence alignments trace to localize and catch different mutant strains in United possibly to transmit severe deadly threat to humans. Studies about the biological symptom of SARS-CoV-2 in clinic animal and humans will be applied and manipulated to find mechanisms and shield the light for understanding the origin of pandemic crisis.


Asunto(s)
Betacoronavirus/genética , Genoma Viral , Sistemas de Lectura Abierta , Glicoproteína de la Espiga del Coronavirus/fisiología , Humanos , Filogenia , Mutación Puntual , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus/genética
13.
J Chin Med Assoc ; 83(6): 537-543, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32349035

RESUMEN

BACKGROUND: China announced an outbreak of new coronavirus in the city of Wuhan on December 31, 2019; lash to now, the virus transmission has become pandemic worldwide. Severe cases from the Huanan Seafood Wholesale market in Wuhan were confirmed pneumonia with a novel coronavirus (2019-nCoV). Understanding the molecular mechanisms of genome selection and packaging is critical for developing antiviral strategies. Thus, we defined the correlation in 10 severe acute respiratory syndrome coronavirus (SARS-CoV2) sequences from different countries to analyze the genomic patterns of disease origin and evolution aiming for developing new control pandemic processes. METHODS: We apply genomic analysis to observe SARS-CoV2 sequences from GenBank (http://www.ncbi.nim.nih.gov/genebank/): MN 908947 (China, C1), MN985325 (USA: WA, UW), MN996527 (China, C2), MT007544 (Australia: Victoria, A1), MT027064 (USA: CA, UC), MT039890 (South Korea, K1), MT066175 (Taiwan, T1), MT066176 (Taiwan, T2), LC528232 (Japan, J1), and LC528233 (Japan, J2) for genomic sequence alignment analysis. Multiple Sequence Alignment by Clustalw (https://www.genome.jp/tools-bin/clustalw) web service is applied as our alignment tool. RESULTS: We analyzed 10 sequences from the National Center for Biotechnology Information (NCBI) database by genome alignment and found no difference in amino acid sequences within M and N proteins. There are two amino acid variances in the spike (S) protein region. One mutation found from the South Korea sequence is verified. Two possible "L" and "S" SNPs found in ORF1ab and ORF8 regions are detected. CONCLUSION: We performed genomic analysis and comparative multiple sequences of SARS-CoV2. Studies about the biological symptoms of SARS-CoV2 in clinic animals and humans will manipulate an understanding on the origin of pandemic crisis.


Asunto(s)
Betacoronavirus/genética , Genoma Viral , Secuencia de Aminoácidos , Polimorfismo de Nucleótido Simple , SARS-CoV-2 , Alineación de Secuencia , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética
14.
Biosci Rep ; 33(5)2013 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-23883094

RESUMEN

Androgen plays an important role in the pathogenesis of PCa (prostate cancer). Previously, we identified GNMT (glycine N-methyltransferase) as a tumour susceptibility gene and characterized its promoter region. Besides, its enzymatic product-sarcosine has been recognized as a marker for prognosis of PCa. The goals of this study were to determine whether GNMT is regulated by androgen and to map its AREs (androgen response elements). Real-time PCR analyses showed that R1881, a synthetic AR (androgen receptor) agonist induced GNMT expression in AR-positive LNCaP cells, but not in AR-negative DU145 cells. In silico prediction showed that there are four putative AREs in GNMT-ARE1, ARE2 and ARE3 are located in the intron 1 and ARE4 is in the intron 2. Consensus ARE motif deduced from published AREs was used to identify the fifth ARE-ARE5 in the coding region of exon 1. Luciferase reporter assay found that only ARE5 mediated the transcriptional activation of R1881. ARE3 overlaps with a YY1 [Yin and Yang 1 (motif (CaCCATGTT, +1118/+1126)] that was further confirmed by antibody supershift and ChIP (chromatin immunoprecipitation) assays. EMSA (electrophoretic mobility shift assay) and ChIP assay confirmed that AR interacts with ARE5 in vitro and in vivo. In summary, GNMT is an AR-targeted gene with its functional ARE located at +19/+33 of the first exon. These results are valuable for the study of the influence of androgen on the gene expression of GNMT especially in the pathogenesis of cancer.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Glicina N-Metiltransferasa/genética , Elementos de Respuesta , Antagonistas de Receptores Androgénicos/farmacología , Anilidas/farmacología , Secuencia de Bases , Sitios de Unión , Línea Celular Tumoral , Exones , Humanos , Masculino , Metribolona/farmacología , Nitrilos/farmacología , Sistemas de Lectura Abierta , Neoplasias de la Próstata , Unión Proteica , Receptores Androgénicos/metabolismo , Análisis de Secuencia de ADN , Congéneres de la Testosterona/farmacología , Compuestos de Tosilo/farmacología , Transcripción Genética
15.
PLoS One ; 3(2): e1540, 2008 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-18253488

RESUMEN

BACKGROUND: Mesenchymal stem cells (MSCs) are a pluripotent cell type that can differentiate into adipocytes, osteoblasts and other cells. The reciprocal relationship between adipogenesis and osteogenesis was previously demonstrated; however, the mechanisms remain largely unknown. METHODS AND FINDINGS: We report that activation of PKA by 3-isobutyl-1 methyl xanthine (IBMX) and forskolin enhances adipogenesis, the gene expression of PPARgamma2 and LPL, and downregulates the gene expression of Runx2 and osteopontin, markers of osteogenesis. PKA activation also decreases the ratio of Receptor Activator of the NF-kappaB Ligand to Osteoprotegerin (RANKL/OPG) gene expression - the key factors of osteoclastogenesis. All these effects are mediated by the cAMP/PKA/CREB pathway by suppressing leptin, and may contribute to PKA stimulators-induced in vivo bone loss in developing zebrafish. CONCLUSIONS: Using MSCs, the center of a newly proposed bone metabolic unit, we identified cAMP/PKA signaling, one of the many signaling pathways that regulate bone homeostasis via controlling cyto-differentiation of MSCs and altering RANKL/OPG gene expression.


Asunto(s)
Adipogénesis , Proteínas Quinasas Dependientes de AMP Cíclico/fisiología , Leptina/antagonistas & inhibidores , Células Madre Mesenquimatosas/citología , Osteogénesis , Osteoprotegerina/genética , Ligando RANK/genética , Animales , Huesos/metabolismo , Diferenciación Celular , Células Cultivadas , Femenino , Humanos , Células Madre Mesenquimatosas/metabolismo , Persona de Mediana Edad , Osteoprotegerina/análisis , Ligando RANK/análisis , ARN Mensajero/análisis , Transducción de Señal , Pez Cebra
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