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1.
Nature ; 559(7713): 279-284, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29950726

RESUMEN

Accurate replication of DNA requires stringent regulation to ensure genome integrity. In human cells, thousands of origins of replication are coordinately activated during S phase, and the velocity of replication forks is adjusted to fully replicate DNA in pace with the cell cycle1. Replication stress induces fork stalling and fuels genome instability2. The mechanistic basis of replication stress remains poorly understood despite its emerging role in promoting cancer2. Here we show that inhibition of poly(ADP-ribose) polymerase (PARP) increases the speed of fork elongation and does not cause fork stalling, which is in contrast to the accepted model in which inhibitors of PARP induce fork stalling and collapse3. Aberrant acceleration of fork progression by 40% above the normal velocity leads to DNA damage. Depletion of the treslin or MTBP proteins, which are involved in origin firing, also increases fork speed above the tolerated threshold, and induces the DNA damage response pathway. Mechanistically, we show that poly(ADP-ribosyl)ation (PARylation) and the PCNA interactor p21Cip1 (p21) are crucial modulators of fork progression. PARylation and p21 act as suppressors of fork speed in a coordinated regulatory network that is orchestrated by the PARP1 and p53 proteins. Moreover, at the fork level, PARylation acts as a sensor of replication stress. During PARP inhibition, DNA lesions that induce fork arrest and are normally resolved or repaired remain unrecognized by the replication machinery. Conceptually, our results show that accelerated replication fork progression represents a general mechanism that triggers replication stress and the DNA damage response. Our findings contribute to a better understanding of the mechanism of fork speed control, with implications for genomic (in)stability and rational cancer treatment.


Asunto(s)
Estructuras Cromosómicas , Daño del ADN , Replicación del ADN/fisiología , Inestabilidad Genómica , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Línea Celular Tumoral , Estructuras Cromosómicas/efectos de los fármacos , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Daño del ADN/efectos de los fármacos , Replicación del ADN/efectos de los fármacos , Inestabilidad Genómica/efectos de los fármacos , Humanos , Ftalazinas/farmacología , Piperazinas/farmacología , Poli(ADP-Ribosa) Polimerasa-1/antagonistas & inhibidores , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Factores de Tiempo , Proteína p53 Supresora de Tumor/metabolismo
2.
J Neurosci ; 40(47): 9148-9162, 2020 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-33087471

RESUMEN

A single stressful event can cause morphologic and functional changes in neurons and even malfunction of vascular systems, which can lead to acute stress disorder or post-traumatic stress disorder. However, there is a lack of evidence regarding how acute stress impacts neuronal activity, the concurrent vascular response, and the relationship between these two factors, which is defined as neurovascular coupling. Here, using in vivo two-photon imaging, we found that NMDA-evoked calcium transients of excitatory neurons were impaired and that vasodilation of penetrating arterioles was concomitantly disrupted in acutely stressed male mice. Furthermore, acute stress altered the relationship between excitatory neuronal calcium coherence and vascular responses. By measuring NMDA-evoked excitatory and inhibitory neuronal calcium activity in acute brain slices, we confirmed that neuronal coherence both between excitatory neurons and between excitatory and inhibitory neurons was reduced by acute stress but restored by blockade of glucocorticoid receptor signaling. Furthermore, the ratio of sEPSCs to sIPSCs was altered by acute stress, suggesting that the excitation-inhibition balance was disrupted by acute stress. In summary, in vivo, ex vivo, and whole-cell recording studies demonstrate that acute stress modifies excitatory-inhibitory neuronal coherence, disrupts the excitation-inhibition balance, and causes consequent neurovascular coupling changes, providing critical insights into the neural mechanism of stress-induced disorders.SIGNIFICANCE STATEMENT Acute stress can cause pathologic conditions, such as acute stress disorder and post-traumatic stress disorder, by affecting the functions of neurons and blood vessels. However, investigations into the impacts of acute stress on neurovascular coupling, the tight connection between local neural activity and subsequent blood flow changes, are lacking. Through investigations at the in vivo, ex vivo, and whole-cell recording levels, we found that acute stress alters the NMDA-evoked vascular response, impairs the function and coherence of excitatory and inhibitory neurons, and disrupts the excitatory and inhibitory balance. These novel findings provide insights into the relevance of the excitatory-inhibitory balance, neuronal coherence, and neurovascular coupling to stress-induced disorders.


Asunto(s)
Neuronas/patología , Acoplamiento Neurovascular/fisiología , Estrés Psicológico/patología , Enfermedad Aguda , Animales , Señalización del Calcio , Circulación Cerebrovascular/fisiología , Corticosterona/fisiología , Técnicas In Vitro , Masculino , Ratones , Ratones Endogámicos C57BL , N-Metilaspartato/farmacología , Inhibición Neural , Técnicas de Placa-Clamp , Receptores de Glucocorticoides/fisiología , Restricción Física
3.
Genes Dev ; 27(22): 2459-72, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-24240236

RESUMEN

Cdc7 kinase regulates DNA replication. However, its role in DNA repair and recombination is poorly understood. Here we describe a pathway that stabilizes the human Cdc7-ASK (activator of S-phase kinase; also called Dbf4), its regulation, and its function in cellular responses to compromised DNA replication. Stalled DNA replication evoked stabilization of the Cdc7-ASK (Dbf4) complex in a manner dependent on ATR-Chk1-mediated checkpoint signaling and its interplay with the anaphase-promoting complex/cyclosome(Cdh1) (APC/C(Cdh1)) ubiquitin ligase. Mechanistically, Chk1 kinase inactivates APC/C(Cdh1) through degradation of Cdh1 upon replication block, thereby stabilizing APC/C(Cdh1) substrates, including Cdc7-ASK (Dbf4). Furthermore, motif C of ASK (Dbf4) interacts with the N-terminal region of RAD18 ubiquitin ligase, and this interaction is required for chromatin binding of RAD18. Impaired interaction of ASK (Dbf4) with RAD18 disables foci formation by RAD18 and hinders chromatin loading of translesion DNA polymerase η. These findings define a novel mechanism that orchestrates replication checkpoint signaling and ubiquitin-proteasome machinery with the DNA damage bypass pathway to guard against replication collapse under conditions of replication stress.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Daño del ADN , Replicación del ADN , Antígenos CD , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Cadherinas/metabolismo , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1) , Estabilidad de Enzimas , Genes APC/fisiología , Células HEK293 , Células HeLa , Humanos , Unión Proteica , Proteínas Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal
4.
J Neurosci ; 39(50): 10081-10095, 2019 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-31672788

RESUMEN

Neurovascular coupling (NVC), the interaction between neural activity and vascular response, ensures normal brain function by maintaining brain homeostasis. We previously reported altered cerebrovascular responses during functional hyperemia in chronically stressed animals. However, the underlying neuronal-level changes associated with those hemodynamic changes remained unclear. Here, using in vivo and ex vivo experiments, we investigate the neuronal origins of altered NVC dynamics under chronic stress conditions in adult male mice. Stimulus-evoked hemodynamic and neural responses, especially beta and gamma-band local field potential activity, were significantly lower in chronically stressed animals, and the NVC relationship, itself, had changed. Further, using acute brain slices, we discovered that the underlying cause of this change was dysfunction of neuronal nitric oxide synthase (nNOS)-mediated vascular responses. Using FISH to check the mRNA expression of several GABAergic subtypes, we confirmed that only nNOS mRNA was significantly decreased in chronically stressed mice. Ultimately, chronic stress impairs NVC by diminishing nNOS-mediated vasodilation responses to local neural activity. Overall, these findings provide useful information in understanding NVC dynamics in the healthy brain. More importantly, this study reveals that impaired nNOS-mediated NVC function may be a contributory factor in the progression of stress-related diseases.SIGNIFICANCE STATEMENT The correlation between neuronal activity and cerebral vascular dynamics is defined as neurovascular coupling (NVC), which plays an important role for meeting the metabolic demands of the brain. However, the impact of chronic stress, which is a contributory factor of many cerebrovascular diseases, on NVC is poorly understood. We therefore investigated the effects of chronic stress on impaired neurovascular response to sensory stimulation and their underlying mechanisms. Multimodal approaches, from in vivo hemodynamic imaging and electrophysiology to ex vivo vascular imaging with pharmacological treatment, patch-clamp recording, FISH, and immunohistochemistry revealed that chronic stress-induced dysfunction of nNOS-expressing interneurons contributes to NVC impairment. These findings will provide useful information to understand the role of nNOS interneurons in NVC in normal and pathological conditions.


Asunto(s)
Circulación Cerebrovascular/fisiología , Neuronas GABAérgicas/fisiología , Interneuronas/fisiología , Acoplamiento Neurovascular/fisiología , Estrés Fisiológico/fisiología , Potenciales de Acción/fisiología , Animales , Encéfalo/fisiología , Masculino , Ratones , Óxido Nítrico Sintasa de Tipo I/metabolismo , Vasodilatación/fisiología
5.
Sensors (Basel) ; 18(1)2018 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-29351218

RESUMEN

In this paper, we introduce a transparent fingerprint sensing system using a thin film transistor (TFT) sensor panel, based on a self-capacitive sensing scheme. An armorphousindium gallium zinc oxide (a-IGZO) TFT sensor array and associated custom Read-Out IC (ROIC) are implemented for the system. The sensor panel has a 200 × 200 pixel array and each pixel size is as small as 50 µm × 50 µm. The ROIC uses only eight analog front-end (AFE) amplifier stages along with a successive approximation analog-to-digital converter (SAR ADC). To get the fingerprint image data from the sensor array, the ROIC senses a capacitance, which is formed by a cover glass material between a human finger and an electrode of each pixel of the sensor array. Three methods are reviewed for estimating the self-capacitance. The measurement result demonstrates that the transparent fingerprint sensor system has an ability to differentiate a human finger's ridges and valleys through the fingerprint sensor array.

6.
J Phys Ther Sci ; 25(11): 1433-5, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24396205

RESUMEN

[Purpose] The purpose of this study was to investigate the effect of muscle vibration applied to the lower extremities on static postural balance of patients with Parkinson's disease (PD). [Subjects] Seven subjects with Parkinson's disease participated in this study. [Methods] The oscillators of vibration were attached to the muscle bellies of the tibialis anterior, gastrocnemius, biceps femoris, and rectus femoris on both sides of the lower extremities with adhesive tape. A vibration frequency of 60 Hz was used to induce static postural reactions. Subjects' center of pressure (COP) sway and peak ground reaction force (GRF) were measured with their eyes open with and without vibration. COP sway and peak GRF (Fx, Fy, Fz) were measured using a force plate (AMTI, Newton, USA), which provides x, y and z coordinates of body movement. [Results] The area of COP sway with vibration was significantly smaller than that with no vibration, but the length of COP sway showed no difference between two conditions. Peak medial-lateral maximum force (Fy) with vibration was significantly higher than that with no vibration, but peak anterior-posterior force (Fx) and peak vertical force (Fz) showed no differences. [Conclusion] These results suggest that vibration applied to the lower extremities can help PD patients control postural balance during quiet standing.

7.
Nat Cell Biol ; 25(12): 1774-1786, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37957325

RESUMEN

The intricate orchestration of enzymatic activities involving nicotinamide adenine dinucleotide (NAD+) is essential for maintaining metabolic homeostasis and preserving genomic integrity. As a co-enzyme, NAD+ plays a key role in regulating metabolic pathways, such as glycolysis and Kreb's cycle. ADP-ribosyltransferases (PARPs) and sirtuins rely on NAD+ to mediate post-translational modifications of target proteins. The activation of PARP1 in response to DNA breaks leads to rapid depletion of cellular NAD+ compromising cell viability. Therefore, the levels of NAD+ must be tightly regulated. Here we show that exogenous NAD+, but not its precursors, has a direct effect on mitochondrial activity. Short-term incubation with NAD+ boosts Kreb's cycle and the electron transport chain and enhances pyrimidine biosynthesis. Extended incubation with NAD+ results in depletion of pyrimidines, accumulation of purines, activation of the replication stress response and cell cycle arrest. Moreover, a combination of NAD+ and 5-fluorouridine selectively kills cancer cells that rely on de novo pyrimidine synthesis. We propose an integrated model of how NAD+ regulates nucleotide metabolism, with relevance to healthspan, ageing and cancer therapy.


Asunto(s)
Glucólisis , NAD , NAD/metabolismo , Redes y Vías Metabólicas , Genómica , Replicación del ADN
8.
Cell Rep ; 42(1): 111979, 2023 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-36640322

RESUMEN

The role of MDC1 in the DNA damage response has been extensively studied; however, its impact on other cellular processes is not well understood. Here, we describe the role of MDC1 in transcription as a regulator of RNA polymerase II (RNAPII). Depletion of MDC1 causes a genome-wide reduction in the abundance of actively engaged RNAPII elongation complexes throughout the gene body of protein-encoding genes under unperturbed conditions. Decreased engaged RNAPII subsequently alters the assembly of the spliceosome complex on chromatin, leading to changes in pre-mRNA splicing. Mechanistically, the S/TQ domain of MDC1 modulates RNAPII-mediated transcription. Upon genotoxic stress, MDC1 promotes the abundance of engaged RNAPII complexes at DNA breaks, thereby stimulating nascent transcription at the damaged sites. Of clinical relevance, cancer cells lacking MDC1 display hypersensitivity to RNAPII inhibitors. Overall, we unveil a role of MDC1 in RNAPII-mediated transcription with potential implications for cancer treatment.


Asunto(s)
ARN Polimerasa II , Empalme del ARN , Daño del ADN , ARN Polimerasa II/metabolismo , Transcripción Genética , Humanos
9.
Pediatr Int ; 54(1): 32-8, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21917063

RESUMEN

BACKGROUND: Meridian Massage is a traditional practice that manually stimulates the body's meridian system - the same network of vital energy channels used in acupuncture. The present study was to assess the effect of Meridian Massage on physical growth and infants' health as perceived by mothers. METHODS: A study was conducted in a community health center in Korea. A total of 169 healthy infant-mother dyads were assigned to the Meridian Massage group (n= 89) or the gentle touch massage group (n= 80), based on the mother's preference. All massages were conducted by the mothers for 15 min per session, one time daily over a course of 6 weeks. In each group, the infant's weights, heights, and the number of days with illness as perceived by mothers and related clinic visits were measured. RESULTS: Significant differences were observed in weight and height after 6 weeks between the Meridian group and the gentle touch massage group (P < 0.001). Infants in the Meridian Massage group showed a significantly different number of days with perceived clinic visits compared to those in the control group (P < 0.001). CONCLUSIONS: Meridian Massage may facilitate physical growth and improve infants' health outcome as perceived by mothers. A randomized controlled trial is required to further explore the effects of Meridian Massage in early infancy.


Asunto(s)
Crecimiento y Desarrollo/fisiología , Masaje/métodos , Meridianos , Madres , Estatura/fisiología , Peso Corporal/fisiología , Femenino , Estado de Salud , Humanos , Lactante , Masculino , Percepción , República de Corea
10.
Cell Death Differ ; 29(8): 1639-1653, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35194187

RESUMEN

Viral infections enhance cancer risk and threaten host genome integrity. Although human cytomegalovirus (HCMV) proteins have been detected in a wide spectrum of human malignancies and HCMV infections have been implicated in tumorigenesis, the underlying mechanisms remain poorly understood. Here, we employed a range of experimental approaches, including single-molecule DNA fiber analysis, and showed that infection by any of the four commonly used HCMV strains: AD169, Towne, TB40E or VR1814 induced replication stress (RS), as documented by host-cell replication fork asymmetry and formation of 53BP1 foci. The HCMV-evoked RS triggered an ensuing host DNA damage response (DDR) and chromosomal instability in both permissive and non-permissive human cells, the latter being particularly relevant in the context of tumorigenesis, as such cells can survive and proliferate after HCMV infection. The viral major immediate early enhancer and promoter (MIEP) that controls expression of the viral genes IE72 (IE-1) and IE86 (IE-2), contains transcription-factor binding sites shared by promoters of cellular stress-response genes. We found that DNA damaging insults, including those relevant for cancer therapy, enhanced IE72/86 expression. Thus, MIEP has been evolutionary shaped to exploit host DDR. Ectopically expressed IE72 and IE86 also induced RS and increased genomic instability. Of clinical relevance, we show that undergoing standard-of-care genotoxic radio-chemotherapy in patients with HCMV-positive glioblastomas correlated with elevated HCMV protein markers after tumor recurrence. Collectively, these results are consistent with our proposed concept of HCMV hijacking transcription-factor binding sites shared with host stress-response genes. We present a model to explain the potential oncomodulatory effects of HCMV infections through enhanced replication stress, subverted DNA damage response and induced genomic instability.


Asunto(s)
Citomegalovirus , Daño del ADN , Carcinogénesis/genética , Citomegalovirus/genética , Citomegalovirus/metabolismo , Inestabilidad Genómica , Humanos , Regiones Promotoras Genéticas , Replicación Viral
11.
J Clin Hypertens (Greenwich) ; 23(7): 1452-1456, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34080288

RESUMEN

People with HIV (PWH) have a >2-fold greater risk for development of cardiovascular disease (CVD), which may be associated with abnormalities in 24-h ambulatory blood pressure measurement (ABPM) profile. We conducted a nested case-control study of ABPM in 137 PWH and HIV-uninfected controls with normal and high clinic blood pressure (BP) in Tanzania. Nocturnal non-dipping of heart rate (HR) was significantly more common among PWH than HIV-uninfected controls (p = .01). Nocturnal non-dipping of BP was significantly more common in PWH with normal clinic BP (p = .048). Clinical correlates of nocturnal non-dipping were similar in PWH and HIV-uninfected adults and included higher BMI, higher CD4+ cell count, and high C-reactive protein for HR and markers of renal disease for BP. In conclusion, nocturnal non-dipping of both BP and HR was more common in PWH but further research is needed to determine causes and consequences of this difference.


Asunto(s)
Infecciones por VIH , Hipertensión , Adulto , Presión Sanguínea , Monitoreo Ambulatorio de la Presión Arterial , Estudios de Casos y Controles , Ritmo Circadiano , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Frecuencia Cardíaca , Humanos , Hipertensión/epidemiología , Tanzanía/epidemiología
12.
Am J Hypertens ; 33(12): 1087-1091, 2020 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-32776154

RESUMEN

BACKGROUND: Hypertensive urgency is associated with a high risk for cardiovascular events and mortality in the United States and Europe, but data from low-income countries and interventions to improve outcomes are lacking. METHODS: We conducted a 1-year prospective study of the prevalence and outcomes of hypertensive urgency (blood pressure (BP) ≥180 mm Hg/120 mm Hg without end-organ damage) in a busy outpatient clinic in Tanzania. RESULTS: Of 7,600 consecutive adult outpatients screened with 3 unattended automated BP measurements according to standard protocol, the prevalence of hypertensive crisis was 199/7,600 (2.6%) (BP ≥180 mm Hg/120 mm Hg) and the prevalence of hypertensive urgency was 164/7,600 (2.2%). Among 150 enrolled patients with hypertensive urgency, median age was 62 years (54-68), 101 (67.3%) were women, and 53 (35%) were either hospitalized or died within 1 year. In a multivariate model, the strongest predictor of hospitalization/death was self-reported medication adherence on a 3 question scale (hazard ratio: 0.06, P < 0.001); 90% of participants with poor adherence were hospitalized or died within 1 year. CONCLUSIONS: Patients with hypertensive urgency in Africa are at high risk of poor outcomes. Clinicians can identify the patients at highest risk for poor outcomes with simple questions related treatment adherence. New interventions are needed to improve medication adherence in patients with hypertensive urgency.


Asunto(s)
Hospitalización/estadística & datos numéricos , Hipertensión Maligna/epidemiología , Hipertensión/epidemiología , Cumplimiento de la Medicación/estadística & datos numéricos , Mortalidad , Anciano , Instituciones de Atención Ambulatoria , Antihipertensivos/uso terapéutico , Femenino , Humanos , Hipertensión/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Tanzanía/epidemiología
13.
J Med Food ; 23(8): 870-878, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32609563

RESUMEN

We sought to investigate the effect of extracts from Rosa gallica petals (RPE) on skin whitening and anti-wrinkle activity. Tyrosinase activity was attenuated by RPE treatment, concomitant with the reduction of melanin accumulation in human B16F10 melanoma. Treatment of the facial skin of volunteers in a clinical trial with an RPE-containing formulation enhanced skin brightness (L* value) significantly. The underlying mechanism responsible was determined to be associated with mitogen-activated protein kinase (MAPK) activation. In addition, RPE exhibited anti-wrinkle formation activity of human dermal fibroblasts by suppressing matrix metalloproteinase (MMP)-1 level. In vivo study, RPE also inhibited solar ultraviolet-stimulated MMP-1 level by c-Jun regulation. Overall, our findings indicate that RPE evokes skin whitening and anti-wrinkle formation activity by regulating intracellular signaling, supporting its utility as an ingredient for skin whitening and anti-wrinkle cosmetic products.


Asunto(s)
Extractos Vegetales/farmacología , Rosa/química , Envejecimiento de la Piel/efectos de los fármacos , Preparaciones para Aclaramiento de la Piel/farmacología , Piel/efectos de los fármacos , Células Cultivadas , Fibroblastos , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Metaloproteinasa 1 de la Matriz/metabolismo , Melaninas/metabolismo , Melanoma Experimental , Rayos Ultravioleta
14.
Food Sci Biotechnol ; 28(5): 1439-1446, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31695942

RESUMEN

The anti-skin inflammatory activities of rose petal extracts have been described in our previous study. Because skin inflammation is closely linked to skin aging, our study investigated the effects of Rosa gallica petals on skin aging-related activities such as skin whitening and anti-wrinkle properties. Each sample was prepared via extraction using different ethanol ratios with the objective of evaluationg optimal extraction conditions for industrial application. Aqueous 50% (v/v) EtOH extract of R. gallica petal significantly suppressed tyrosinase activity, melanin production, and solar UV-induced matrix metalloproteinase-1, a hall mark of wrinkle formation. In addition, the aqueous 50% (v/v) EtOH extract showed the highest antioxidative effect and had highest flavonoid contents, consistent with the reported anti-aging effects. Overall, our findings suggest that R. gallica petals extracts exhibit anti-aging effects. Furthermore, 50% EtOH extraction, in particular, was optimal for the highest anti-aging, and anti-oxidative effects as well as to obtain the highest flavonoid content.

15.
J Med Virol ; 80(8): 1337-43, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18551606

RESUMEN

Few reports have detailed mutation frequencies and mutation patterns in the entire X region according to clinical status. The aims of this study were to elucidate the relationships between mutation patterns and their frequencies in the X region and clinical status in a Korean cohort and determine specific X mutation types, related closely with liver disease progression. All X mutations were determined by direct sequencing in 184 patients with different clinical features. Mutation rates in the X region in patients with more severe liver disease, hepatocellular carcinoma (HCC) (3.6%) or liver cirrhosis (4%) were always significantly higher than in patients with corresponding less severe forms, chronic hepatitis (2.9%) or asymptomatic carriers (2.1%), but no significant difference in mutation rates was found in terms of HBeAg serostatus. All five mutation types (V5M/L, P38S, H94Y, I127T/N, and K130M and V131I) affecting the six codons were found to be related significantly to clinical severity. Among these, two mutation types (V5M/L and K130M and V131I) were observed more frequently in HBeAg negative patients than in HBeAg positive patients. In conclusion, the results suggest that an accumulation of mutations in the X region contributes to disease progression in chronic patients, at least Korean patients with genotype C. Specific mutation types appears to be related more to severe liver diseases such as HCC or liver cirrhosis. In particular, a novel mutation type (V5M/L) discovered firstly during the present study was found to be associated significantly with HCC.


Asunto(s)
Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/genética , Hepatitis B Crónica/fisiopatología , Mutación , Índice de Severidad de la Enfermedad , Transactivadores/genética , Adulto , Anciano , Secuencia de Aminoácidos , Carcinoma Hepatocelular/epidemiología , Carcinoma Hepatocelular/fisiopatología , Carcinoma Hepatocelular/virología , Femenino , Genotipo , Virus de la Hepatitis B/patogenicidad , Hepatitis B Crónica/epidemiología , Hepatitis B Crónica/virología , Humanos , Corea (Geográfico)/epidemiología , Cirrosis Hepática/epidemiología , Cirrosis Hepática/fisiopatología , Cirrosis Hepática/virología , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Prevalencia , Proteínas Reguladoras y Accesorias Virales
16.
Oncol Lett ; 15(4): 6043-6049, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29556318

RESUMEN

A previous study reported that a novel dammarane-type triterpene saponin, ginsenoside-Rg18, derived from the root of Panax ginseng, displayed hydroxyl radical scavenging, anti-bacterial and cytotoxic activities. However, the underlying molecular mechanisms of its anti-proliferative effect on non-small cell lung cancer (NSCLC) A549 cells remains unclear. In the present study, it was determined that Rg18 inhibited the proliferation of A549 cells with a half-maximal inhibitory concentration of 150 µM. Flow cytometry analysis indicated that cell cycle progression was blocked by Rg18 at G1 phase in A549 cells, which was accompanied by downregulation of cyclin-dependent kinase 2 (CDK2), CDK4, CDK6, cyclin D1, cyclin D2, cyclin E and phosphorylated retinoblastoma protein expression at the protein level. In addition, the CDK inhibitors (CDKNs), CDKN1A and CDKN1B, were upregulated following Rg18 treatment. Furthermore, Rg18 treatment resulted in the intracellular accumulation of reactive oxygen species (ROS), and a dose-dependent inhibition of p38 mitogen activated protein kinase (p38), c-Jun N-terminal kinase (JNK) and nuclear factor-κB (NF-κB)/p65 phosphorylation. Taken together, Rg18-mediated G1 phase arrest was closely associated with the generation of intracellular ROS, and p38, JNK and NF-κB/p65 inhibition in A549 human NSCLC cells.

17.
Food Sci Nutr ; 6(8): 2560-2567, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30510758

RESUMEN

The aim of this study was to investigate the skin anti-inflammatory activity of rose petal extract (RPE) and the mechanisms underlying this phenomenon. Recently, flowers have been considered as dietary resources owing to their biological activities, such as inhibition of nephritis and hemorrhoids. The Rosa plant exerts various biological functions, including antioxidant and anti-microbiological activities. Herein, we confirmed the skin anti-inflammatory activity of RPE upon solar UV (sUV) exposure. RPE reduced sUV-induced COX-2 expression as well as expressions of several cytokines. Activation of MKK4-JNK, MEK-ERK, and MKK3-p38 signaling pathways, which are associated with cytokine production, was also attenuated by RPE treatment. We hypothesized these RPE-induced changes are because of its antioxidant activity, because RPE displayed drastic radical scavenging and oxygen radical absorbance capacity (ORAC). Furthermore, high anthocyanins, polyphenols, and flavonoids contents were found in RPE. Hence, these results indicated the skin anti-inflammatory activity of RPE is because of antioxidant activity.

18.
Oxid Med Cell Longev ; 2018: 5967150, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29849904

RESUMEN

Kaempferia parviflora (Krachaidum (KD)) is a traditional herbal medicine and has properties that are beneficial for human health. In the current study, we sought to investigate the anti-inflammatory properties of KD extract (KPE). In mouse skin tissue, UV light representing solar wavelengths (sUV) increased COX-2 expression, while treatment with KPE reduced this effect. The anti-inflammatory activity of KPE was confirmed in in vitro models. MAPK signaling pathways were activated by sUV irradiation, and this was also repressed in the presence of KPE treatment. It is assumed that the anti-inflammatory activity of KPE is caused by the antioxidative effect. Furthermore, we confirmed the critical role of oxidative stress in sUV-induced COX-2 expression. We analyzed the polyphenol composition of KPE. Of the polyphenols identified, gallic acid, apigenin, and tangeretin were identified as the major polyphenols (at 9.31 ± 1.27, 2.37 ± 0.14, and 2.15 ± 0.19 µg/mg dry weight, resp.). Collectively, these findings show that in the presence of sUV irradiation, KD has anti-inflammatory properties and antioxidative effects in the skin.


Asunto(s)
Antioxidantes/uso terapéutico , Medicina de Hierbas/métodos , Zingiber officinale/química , Animales , Antioxidantes/farmacología , Humanos , Ratones
19.
J Ginseng Res ; 42(2): 165-174, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29719463

RESUMEN

BACKGROUND: Extended endoplasmic reticulum (ER) stress may initiate apoptotic pathways in cancer cells, and ER stress has been reported to possibly increase tumor death in cancer therapy. We previously reported that caspase-8 played an important role in compound K-induced apoptosis via activation of caspase-3 directly or indirectly through Bid cleavage, cytochrome c release, and caspase-9 activation in HL-60 human leukemia cells. The mechanisms leading to apoptosis in A549 and SK-MES-1 human lung cancer cells and the role of ER stress have not yet been understood. METHODS: The apoptotic effects of compound K were analyzed using flow cytometry, and the changes in protein levels were determined using Western blot analysis. The intracellular calcium levels were monitored by staining with Fura-2/AM and Fluo-3/AM. RESULTS: Compound K-induced ER stress was confirmed through increased phosphorylation of eIF2α and protein levels of GRP78/BiP, XBP-1S, and IRE1α in human lung cancer cells. Moreover, compound-K led to the accumulation of intracellular calcium and an increase in m-calpain activities that were both significantly inhibited by pretreatment either with BAPTA-AM (an intracellular Ca2+ chelator) or dantrolene (an RyR channel antagonist). These results were correlated with the outcome that compound K induced ER stress-related apoptosis through caspase-12, as z-ATAD-fmk (a specific inhibitor of caspase-12) partially ameliorated this effect. Interestingly, 4-PBA (ER stress inhibitor) dramatically improved the compound K-induced apoptosis. CONCLUSION: Cell survival and intracellular Ca2+ homeostasis during ER stress in human lung cancer cells are important factors in the induction of the compound K-induced apoptotic pathway.

20.
J Ginseng Res ; 41(3): 428-433, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28701887

RESUMEN

BACKGROUND: In this study, the fermentation of ginseng seeds was hypothesized to produce useful physiologically-active substances, similar to that observed for fermented ginseng root. Ginseng seed was fermented using Bacillus, Pediococcus, and Lactobacillus strains to extract ginseng seed oil, and the extraction yield, color, and quantity of phenolic compounds, fatty acids, and phytosterol were then analyzed. METHODS: The ginseng seed was fermented inoculating 1% of each strain on sterilized ginseng seeds and incubating the seeds at 30°C for 24 h. Oil was extracted from the fermented ginseng seeds using compression extraction, solvent extraction, and supercritical fluid extraction. RESULTS AND CONCLUSION: The color of the fermented ginseng seed oil did not differ greatly according to the fermentation or extraction method. The highest phenolic compound content recovered with the use of supercritical fluid extraction combined with fermentation using the Bacillus subtilis Korea Food Research Institute (KFRI) 1127 strain. The fatty acid composition did not differ greatly according to fermentation strain and extraction method. The phytosterol content of ginseng seed oil fermented with Bacillus subtilis KFRI 1127 and extracted using the supercritical fluid method was highest at 983.58 mg/100 g. Therefore, our results suggested that the ginseng seed oil fermented with Bacillus subtilis KFRI 1127 and extracted using the supercritical fluid method can yield a higher content of bioactive ingredients, such as phenolics, and phytosterols, without impacting the color or fatty acid composition of the product.

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