RESUMO
A four-step synthetic process has been developed to prepare 1,3,5,8-tetrahydroxyxanthone (2a) and its isomer 1,3,7,8-tetrahydroxyxanthone (2b). 25 more xanthones were also synthesized by a modified scheme. Xanthone 2a was identified as the most active inhibitor against both α-glucosidase and aldose reductase (ALR2), with IC50 values of 7.8 ± 0.5 µM and 63.2 ± 0.6 nM, respectively, which was far active than acarbose (35.0 ± 0.1 µM), and a little more active than epalrestat (67.0 ± 3.0 nM). 2a was also confirmed as the most active antioxidant in vitro with EC50 value of 8.9 ± 0.1 µM. Any structural modification including methylation, deletion, and position change of hydroxyl group in 2a will cause an activity loss in inhibitory and antioxidation. By applying a H2 O2 -induced oxidative stress nematode model, it was confirmed that xanthone 2a can be absorbed by Caenorhabditis elegans and is bioavailable to attenuate in vivo oxidative stress, including the effects on lifespan, superoxide dismutase, Catalase, and malondialdehyde. 2a was verified with in vivo hypoglycemic effect and mitigation of embryo malformations in high glucose. All our data support that xanthone 2a behaves triple roles and is a potential agent to treat diabetic mellitus, gestational diabetes mellitus, and diabetic complications.
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Complicações do Diabetes , Diabetes Mellitus , Xantonas , Humanos , Relação Estrutura-Atividade , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/química , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo , Complicações do Diabetes/tratamento farmacológico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Xantonas/farmacologia , Xantonas/uso terapêutico , Simulação de Acoplamento Molecular , Diabetes Mellitus/tratamento farmacológicoRESUMO
Cannabis is the most frequently used illicit drug in the world. Cross-sectional neuroimaging studies have revealed that chronic cannabis exposure and the development of cannabis use disorders may affect cerebllar morphology. However, cross-sectional studies cannot make a conclusive distinction between causes and consequences, and there is a lack of longitudinal neuroimaging studies. In the current study, we used longitudinal neuroimaging data to explore whether persistent cannabis use and higher levels of cannabis exposure in young adults are related to cerebellar thickness alterations. Twenty heavy cannabis users (CBs) and 22 non-cannabis-using controls (HCs) completed a comprehensive psychological assessment and a T1-structural MRI scan at baseline and a 3-year follow-up. Except for lobuleVIIB, all cerebellar subregions showed significant effects of age in both the CB and HC groups. Both VI and CrusI had higher rates of increase in CBs than in HCs. In addition, we examined the relationship between changes in cerebellar thickness and cannabis use characteristics. We found that alterations in lobule VI and CrusI were related to the age at onset first cannabis use but not the age at onset frequent cannabis use. The changes in lobule VI and CrusI were associated with the CUDIT score, even when controlling for the AUDIT score. The results indicated that an increased rate of cerebellar thickness is a risk factor for heavy cannabis use in early adulthood. Cannabis use affects the cerebellar structure, and monitoring cerebellar structural alterations that could be used as biomarkers may help guide the development of clinical tools.
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Cannabis/efeitos adversos , Cerebelo/efeitos dos fármacos , Cerebelo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idade de Início , Encéfalo/diagnóstico por imagem , Estudos de Casos e Controles , Feminino , Humanos , Estudos Longitudinais , Masculino , Fumar Maconha , Adulto JovemRESUMO
The purpose of this meta-analysis was to investigate the immediate and long-term effects of intervention for children with primary speech and language delays/disorders and to explore whether some characteristics of interventions, specifics of the study and research participants moderate the magnitude of the effectiveness of interventions. Using the random effect model, we pooled the effect size and conducted a publication bias evaluation, a moderating effect analysis in CMA 2.0. Results of a random effects model analysis demonstrated a moderate immediate effect (g = 0.70), whereas the long-term efficacy was small (g = 0.23). Additionally, type of measure, language of intervention, parental involvement, intervention content and study quality, as well as the duration of intervention, significantly moderated the effect size of intervention effectiveness.
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Transtornos do Desenvolvimento da Linguagem , Fala , Criança , China , Humanos , Transtornos do Desenvolvimento da Linguagem/terapia , Pais , Estados UnidosRESUMO
Background: Neuroglial heterotopia is a rare lesion composed of differentiated neuroectodermal cells that manifest in extracranial locations, with the majority of cases predominantly occurring in the head and neck region. Retroperitoneal neuroglial heterotopia is exceptionally rare, with isolated cases published in the scientific literature. Case report: Here, we present the case of a 3-year-old girl who was admitted without clinical signs but presented with a palpable abdominal mass. Ultrasonography and computed tomography scans revealed a sizable cystic lesion within the retroperitoneal space. Subsequently, laparoscopic resection was performed. Histological examination unveiled neuroglial cell-lined cysts encompassing fibrous connective tissue, ganglia, glial tissue, and nerve bundles. Notably, distinct areas and cell types exhibited expression of S100, glial fibrillary acidic protein, and neuron-specific enolase. Follow-up assessments revealed no relapses or late complications. Conclusion: In cases of retroperitoneal neuroglial heterotopia, most children may remain asymptomatic without any congenital anomalies. Despite their detectability through imaging, accurate preoperative diagnosis is seldom achieved. Generally, a favorable prognosis follows complete surgical resection, although further cases are required to confirm its long-term efficacy, necessitating extended follow-up for verification.
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BACKGROUND: Genistein has been limited in clinical application due to its low bioavailability, extremely poor liposolubility, and fast glycosylation rate, though it possesses anti-breast cancer activity. Therefore, the discovery of novel genistein derivatives is an urgency. OBJECTIVE: To enhance the anti-breast cancer activity of genistein, a series of novel fluorinated genistein derivatives were synthesized. METHODS: Their in vitro antitumor activity was investigated by the MTT assay against three cancer cell lines, via, MDA-MB-231, MCF-7, and MDA-MB-435, respectively. RESULTS: Analogs 1d, 2b, and 3b showed remarkable anticancer activities compared to tamoxifen, a clinical anti-breast cancer drug on the market. CONCLUSION: The activities against breast cancer of genistein were enhanced by introducing the 7- alkoxyl group and fluorine atom into the B-ring. Therefore, these compounds may be potential candidates for treating breast cancer.
Assuntos
Antineoplásicos , Neoplasias da Mama , Humanos , Feminino , Genisteína/farmacologia , Genisteína/uso terapêutico , Neoplasias da Mama/patologia , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico , Linhagem Celular , Proliferação de Células , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura MolecularRESUMO
Although previous studies have found that ADHD is characterized by a delay in cortical maturation, it is not clear whether this phenomenon was secondary to developmental trajectories in subcortical regions (caudate, putamen, pallidum, thalamus, hippocampus and amygdala). Using the ADHD-200 dataset, we estimated subcortical volumes in 339 individuals with ADHD and 568 typically developing controls. We defined the growth trajectory of each subcortical structure, delineating a phase of childhood increase followed by an adolescent decrease in subcortical volumes using a quadratic growth model. From these trajectories, the age of attaining peak subcortical volumes was derived and used as an index of subcortical maturation. We found that subcortical structures (caudate, putamen, pallidum, thalamus, hippocampus and amygdala) followed curvilinear trajectories similar to those reported in previous studies. The volumes of these subcortical structures in ADHD were also delayed in the developmental trajectory, which suggested that ADHD may be characterized by a delay in subcortical maturation. This delay may lead to a shift in which individuals with ADHD go through the process of pruning the nerve connections that is part of the normal maturation process during adolescence. Further, we also found that the asymmetric development of subcortical structures was abnormal in ADHD, which resulted from the imbalance of the maturation delay of bilateral subcortical structures. The subcortical maturation delay may play an important role in the pathophysiology of ADHD. Our findings provide new potential targets to investigate the pathophysiology of ADHD.
Assuntos
Tonsila do Cerebelo/diagnóstico por imagem , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico por imagem , Corpo Estriado/diagnóstico por imagem , Hipocampo/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Adolescente , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Tamanho do Órgão , Adulto JovemRESUMO
Cannabis exposure is related to neuroanatomical changes in brain regions rich in cannabinoid receptors, such as the hippocampus. However, researchers have not clearly determined whether persistent heavy cannabis use leads to morphological changes in the hippocampus or whether an earlier age of onset of first cannabis use and/or higher doses of cannabis exposure exacerbate these alterations. In this longitudinal study, we investigated whether continued heavy cannabis use in young adults is associated with an altered hippocampal volume. Twenty heavy cannabis users (CBs) and 22 healthy controls (HCs) underwent a comprehensive psychological assessment and a T1 structural scan at baseline and at a 3-year follow-up visit. Volumes of the hippocampus and its subregions were estimated using volBrain software. Except for the cornu ammonis 2 (CA2)/CA3 subregions, age had significant effects on all hippocampal subregions in both the CB and HC groups. The relative right hippocampal volume and absolute and relative right CA1 volumes displayed a greater rate of decrease in CBs compared to HCs. In addition, we explored the relationship between alterations in hippocampal volume and cannabis use characteristics. Changes in the relative right hippocampal volume and the relative right CA1 volume were related to age at first cannabis use but not to age at onset of frequent cannabis use. Alterations in the relative right hippocampal volume and absolute and relative right CA1 volumes were associated with Cannabis Use Disorder Identification Test (CUDIT) scores. Based on these results, heavy cannabis use in early adulthood is a risk factor for a greater rate of decrease in the volume of the right hippocampus (particularly the right CA1).
Assuntos
Cannabis/efeitos adversos , Hipocampo/efeitos dos fármacos , Hipocampo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Adulto , Encéfalo/diagnóstico por imagem , Estudos de Casos e Controles , Feminino , Humanos , Estudos Longitudinais , Masculino , Fumar Maconha , Receptores de Canabinoides , Adulto JovemRESUMO
Using magnetic resonance imaging to determine neuropathology in autism spectrum disorders, we report findings on the volume of the amygdala and hippocampus in autistic children. The volumes of amygdala, hippocampus and total brain were obtained by volbrain and their volumes were measured in young people (6.5-27.0 years of age) that comes from ABIDE dataset. Although there was no significant difference in total brain capacity between groups, autistic children (6.5-12.0 years of age) had larger right and left absolute and relative amygdala volumes than the control group. There was no difference in amygdala volume between adolescence (13-19 years old) and adults (20-27 years old). Interestingly, the volume of the amygdala in typical developing children increased significantly from 6.5 to 27 years of age. Thus, amygdala in children with autism was initially small, but no age-related increases were observed in normal developing children. The right absolute hippocampal volume of autistic patients was also larger than that of normal adults, but not after controlling the total brain volume. These cross-sectional findings suggest that abnormal patterns of hippocampal and amygdala development continue into adolescence in autistic patients.
Assuntos
Tonsila do Cerebelo/crescimento & desenvolvimento , Transtorno Autístico/diagnóstico por imagem , Hipocampo/crescimento & desenvolvimento , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Fatores Etários , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/patologia , Transtorno Autístico/patologia , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Criança , Estudos Transversais , Feminino , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Humanos , Masculino , Tamanho do Órgão , Adulto JovemRESUMO
Many studies have reported abnormal cerebellar volume in patients with autism spectrum disorder (ASD) and that this abnormal volume can change with age. In the present study, we used CERES, an automated and reliable quantitative analysis tool, and adopted a longitudinal design to examine developmental changes in the cerebellar lobular thickness in ASD and quantified the relationship between cerebellar thickness development and clinical symptoms. Nineteen individuals with ASD (16 males; age, 12.53⯱â¯2.34 years at baseline, interval: 2.33 years) and 14 typically developing controls (TD; 12 males; age, 13.50⯱â¯1.77 years at baseline, interval: 2.31 years) underwent T1-weighted magnetic resonance imaging at two time points. To explore the relationship between cerebellar lobular thickness and the symptoms of ASD, the correlation of Autism Diagnostic Observation Schedule (ADOS) score with lobular thickness data was calculated. The cerebellar lobule thickness decreased in the right Crus II and the Crus II asymmetry was reduced in individuals with ASD. The reduction in lobular thickness and the asymmetry in Crus II were associated with the severity of stereotyped behavior symptoms. Structural differences and behavioral correlations were concentrated in the right cerebellar Crus II. These results emphasize the importance of the potential functional effect of structural differences in cerebellar subregions on ASD and suggest that the changes of thickness in the right cerebellar Crus II are related to the core profile of ASD.
Assuntos
Transtorno do Espectro Autista/patologia , Transtorno do Espectro Autista/fisiopatologia , Transtorno Autístico/patologia , Córtex Cerebelar/patologia , Cerebelo/patologia , Adolescente , Transtorno Autístico/fisiopatologia , Córtex Cerebelar/fisiopatologia , Cerebelo/fisiopatologia , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , MasculinoRESUMO
Notwithstanding an extensive literature about attention-deficit/hyperactivity disorder (ADHD) and brain structure and function, the controversy of ADHD resulting from dysfunction or developmental delay remains unclear. Graph analysis studies have reached consensus about the pattern of increased integration and decreased randomness during childhood and early adulthood. Here, we hypothesized that ADHD is a neurodevelopmental disorder resulting from developmental delay and would show a pattern of decreased integration and increased randomness during childhood and early adulthood compared with typically developing children. To test this hypothesis, publicly available resting-state fMRI data from 102 children with ADHD and 143 typically developing controls (TDC) were compared using graph theoretical analysis. Functional connectivity was estimated using Pearson correlation analysis, and network topology was characterized using small-world (SW) and minimum spanning tree (MST) properties. The mean strength of global connectivity was significantly weaker in those with ADHD and was related to ADHD diagnosis scores. Significant group differences were observed for SW(clustering coefficient, path length, global and local efficiency) and MST (leaf number, kappa and hierarchy) topology. In addition, except for global efficiency, all of these parameters showed significant correlations with ADHD-related disability. The topology of SW and MST showed less integration and more randomness, which confirmed that ADHD is a disorder associated with developmental delay. Moreover, the topology of resting-state functional networks in children with ADHD that show abnormalities was associated with the degree of disability, which can be considered neurological hallmarks of neurodevelopmental disorders and may facilitate the evaluation and monitoring of clinical status in individuals with ADHD.
Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Mapeamento Encefálico , Criança , Análise por Conglomerados , Estudos de Coortes , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem , Testes Neuropsicológicos , Índice de Gravidade de DoençaRESUMO
PURPOSE: In an increasingly aging society, it is of great importance to consider trajectories of subcortical volumes at different ages for understanding biological markers of aging. Thus, we investigated sex, age, and their interactions on subcortical volumes, including the basal ganglia (caudate, putamen, accumbens, and pallidum), thalamus, hippocampus, and amygdala. METHODS: We analyzed the adult lifespan trajectory of subcortical volumes and asymmetries in 563 healthy subjects aged from 19 to 86 using magnetic resonance imaging (MRI) data from the publicly available 7IXI data set. RESULTS: The sex made strong contributions to the trajectories of subcortical volumes with aging, including the right putamen, right pallidum, bilateral thalamus, hippocampus, and amygdala. The volume of the right putamen, right pallidum, and right thalamus decreased more rapidly in males than in females, and the volume of the left thalamus, bilateral hippocampus, and amygdala in males followed a quadratic model, while those in females followed a linear decline model. The asymmetries in the caudate and hippocampus showed a linear decline, and a sex and age interaction was found in the hippocampus; that is, the asymmetry in the hippocampus decreased only in the males and not in the females. Changes in the accumbens and pallidum fit quadratic trajectories, in which females increased until 39.26 years old in the accumbens asymmetry and then began to rapidly decline, and males showed a linear decline. The asymmetry in the pallidum in males and females showed a slow decreasing period until almost 45 years of age and then increased. CONCLUSION: The results suggest that compared with females, males have a faster decline in the volume of the right putamen, right pallidum, and right thalamus, while aging occurred later but also faster in the left thalamus, bilateral hippocampus, and amygdala. Interestingly, we found the inflection point in the thalamus, bilateral hippocampus, and amygdala volume in the quadratic model, and after this point, the volume change accelerated with aging, which may have resulted from the stronger work pressure in the middle-aged men and the low levels of testosterone in the older adults. The interaction of age and sex on individual subcortical structures provides evidence to support the impact of sex on psychopathologies associated with degenerative brain disorders in the elderly. The findings may be significant to investigate the occurrence and prevalence of degenerative brain disorders in males and females. Future studies can focus on the functional and behavioral relations with subcortical structures for preventive measures of related disorders.
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Although studies showed subtle reductions in brain volume in fronto-striatial regions in children with ADHD, there have been limited investigations of volume and lateralizaton in subcortical structures and a paucity of exploration of the influence of gender on these findings. This study aims to examine morphology of subcortical structures and their association with ADHD symptoms in boys and girls as compared to their typically-developing (TD) peers. One hundred and eighty five children aged 7-14 years with and without ADHD were included from ADHD-200 Consortium. Results showed that compared to TD boys, boys with ADHD had reduced accumbens, amygdala and hippocampus volumes. There were no volumetric differences in any structure between ADHD and TD girls. Asymmetry analysis revealed right lateralization compressions within the thalamus in ADHD boys relative to TD boys. The findings suggest a gender dimorphic pattern of differences in subcortical structures in children with ADHD, and a possible neurobiological mechanism where boys with ADHD demonstrate increasing difficulties with hyperactivity/impulsivity.
Assuntos
Tonsila do Cerebelo/fisiopatologia , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Hipocampo/fisiopatologia , Fatores Sexuais , Tálamo/fisiopatologia , Adolescente , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Tamanho do Órgão/fisiologiaRESUMO
Although the spacing effect is one of most robust effects in learning, its cognitive and neural mechanisms are still under investigation. Whether the spacing effect is achieved by reducing neural repetition priming or depends on learning experience is still unclear. In this event-related potential study, participants were asked to memorize 140 novel faces, half under the massed learning condition and the other half under the spaced learning condition. The afterwards recognition tests indicated that participants recognized more items under the spaced learning condition than under the massed learning condition. The electroencephalography data suggested that spaced learning was associated with a reduced familiarity effect in frontal N400. Remembered faces showed smaller repetition priming than forgotten faces under both learning conditions and spaced learning significantly reduced repetition suppression. Although no direct association was found between repetition priming and episodic memory, the difference in quantity between spaced learning and massed learning in the repetition priming can predict the different quantities in the recognition memory. These results suggest that the neural mechanism of the spacing effect is influenced by experience; however, the impact is mainly repetition priming and the spacing effect is still very robust.
Assuntos
Encéfalo/fisiologia , Reconhecimento Facial/fisiologia , Reconhecimento Psicológico/fisiologia , Priming de Repetição/fisiologia , Adolescente , Adulto , Eletroencefalografia , Potenciais Evocados , Feminino , Humanos , Masculino , Análise Multivariada , Testes Neuropsicológicos , Fatores de Tempo , Adulto JovemRESUMO
BACKGROUND: Playing a central role in hepatic fibrosis, hepatic stellate cell (HSC) has made itself the major target of research. The limited supply of HSC, however, can not meet the ever growing need of experiment. Establishment and identification of novel immortalized HSC line thus may be urgently required. METHODS: Primary HSCs were isolated from a normal adult male Sprague-Dawley rat by in situ perfusion with collagenase IV and pronase E, and then were purified by single-step density gradient centrifugation with nycodenz. Once they reached total activation in culture, a new immortalized myofibroblast-like HSC line was established through cellular cloning. Its characteristics were identified by means of immunocytochemical staining, light microscopy, transmission electron microscopy, and growth curve analysis. RESULTS: The novel HSC line, termed HSC-PQ, had a doubling time of about 75 hours in the Dulbecco's modified Eagle medium (DMEM) containing 20% fetal bovine serum. Most of the main morphological characteristics of the differentiated primary HSC could be detected in HSC-PQ cell, while functional features of activated HSC such as alpha-smooth muscle actin, desmin, collagen type I, collagen type III, fibronectin, laminin and other extracellular matrix proteins could also be found in it except for collagen type IV. In contrast, fat droplets and autofluorescence of vitamin A disappeared in the HSC-PQ line. This cell line had been maintained in culture for over 30 passages and more than 1 year with little alternation in biological characteristics. CONCLUSION: A new rat HSC line (HSC-PQ) has been successfully established. It consistently retains the characteristics of activated primary HSC, and has proved to be immortalized.
Assuntos
Linhagem Celular , Hepatócitos/citologia , Hepatócitos/fisiologia , Análise de Variância , Animais , Apoptose/fisiologia , Linhagem Celular Transformada , Proliferação de Células , Citometria de Fluxo , Imuno-Histoquímica , Cirrose Hepática/patologia , Cirrose Hepática/fisiopatologia , Masculino , Microscopia Eletrônica de Varredura , Probabilidade , Ratos , Ratos Sprague-Dawley , Sensibilidade e Especificidade , Coleta de Tecidos e ÓrgãosRESUMO
AIM: To investigate the pathway via which 17beta-estradiol (beta-Est) exerts suppressive effects on rat hepatic fibrosis. METHODS: In vivo study was done in CCl4-induced female hepatofibrotic rats. Fibrosis-suppressive effect of beta-Est (20 microg/kg/d) was evaluated in intact and ovariectomized rat models. Six weeks after the treatment, all the rats were sacrificed and specimens of serum or liver tissue were collected for the studies. Serum liver enzymes, fibrosis markers and estradiol levels were determined by standard enzymatic methods, ELISA and RIA, respectively. Degrees of fibrosis and areas of hepatic stellate cells (HSCs) positive for alpha-smooth muscle actin (alpha-SMA) in the liver were determined by van Gieson (VG) stain and immunohistochemistry. In vitro studies, HSCs were isolated by a combination of pronase-collagenase perfusion and density gradient centrifugation. First-passage HSCs were randomly divided into 10 groups, and different concentrations of beta-Est, 2-hydroxyestradiol (2OHE) or 2-methoxyestradiol (2MeOE) were separately added to the cell groups. After incubation for 72 h, the degree of cell proliferation, collagen production, alpha-SMA or estrogen receptor (ER) expression was determined by MTT assay, ELISA and immunohistochemistry, respectively. RESULTS: Beta-Est treatment reduced aspartate aminotransferase (AST), alanine aminotransferase (ALT), hyaluronic acid (HA) and type IV collagen (C IV) in sera, suppressed hepatic collagen content, decreased the areas of HSCs positive for alpha-SMA significantly in both intact and ovariectomized female hepatofibrotic rats. There was a negative correlation between the percentage of fibrotic area of liver tissue and the serum estradiol level; the calculated correlation coefficient was -0.57 (P<0.01). Beta-Est and its metabolites concentration-dependently (10(-9) mol/L-10(-7) mol/L) inhibited HSC proliferation and collagen synthesis. At the concentration of 10(-7) mol/L, they could inhibit alpha-SMA expression. The order of potency was 2MeOE>2OHE>beta-Est. CONCLUSION: Beta-Est may suppress hepatic fibrosis probably via its biologically active metabolites.
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Tetracloreto de Carbono/toxicidade , Estradiol/metabolismo , Fibrose/induzido quimicamente , Cirrose Hepática Experimental/patologia , Animais , Células Cultivadas , Feminino , Fibrose/metabolismo , Fibrose/patologia , Hepatócitos/citologia , Hepatócitos/metabolismo , Fígado/citologia , Fígado/metabolismo , Fígado/patologia , Ovariectomia , Ratos , Ratos Sprague-DawleyRESUMO
AIM: To assess the effects of somatostatin on proliferation and apoptosis of activated rat hepatic stellate cells (HSCs). METHODS: HSCs isolated from the livers of adult Sprague-Dawley rats (weighing 400-500 g) by in situ perfusion and purified by single-step density gradient centrifugation with Nycodenz, became activated after 10 days' cultivation. Then the apoptotic rate of HSCs treated with different doses of somatostatin for 72 h, was assayed by acridine orange/ethidium bromide fluorescent staining, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling, transmission electron microscopy and flow cytometry, while the proliferation of HSCs was measured by MTT assay. Furthermore, the mechanisms of somatostatin were investigated by cytodynamic analysis. RESULTS: Somatostatin at the concentration of 10(-6)-10(-9) mol/L could decrease the proliferative rate, and promote the apoptosis of activated rat HSCs in a dose-dependent way. Its action was most significant when the concentration reached 10(-6) mol/L or 10(-7) mol/L (P<0.05-0.01). An obvious cell-cycle arrest (G(0)/G(1) arrest) was the important way for somatostatin to exert its action. CONCLUSION: Antiproliferative and proapoptotic effects of low-dose somatostatin on activated rat HSCs can be obtained. These findings reveal its potential antifibrotic action.
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Apoptose/efeitos dos fármacos , Hepatócitos/citologia , Hepatócitos/fisiologia , Somatostatina/farmacologia , Animais , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Hepatócitos/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
BACKGROUND: Somafostatin receptors (SSTRs) have been suggested to involve in mediating the effect of somatostatin on hepatic stellate cells (HSCs) in an activation-dependent way. We, therefore, try to investigate the relationship between expression of SSTRs and activation of rat HSCs. METHODS: HSCs were isolated from rats by in situ perfusion and single-step density gradient centrifugation. SSTR1-5 mRNA levels in the differentiated first passage HSCs were detected by means of a reverse transcription polymerase chain reaction. On the other hand, hepatic fibrosis was induced in adult male Sprague-Dawley rats by carbon tetrachloride intoxication, and the expression of SSTR1-5 in normal as well as fibrotic livers was measured by immunohistochemical staining. RESULTS: SSTR mRNA and SSTR could not be found in freshly isolated rat HSCs or normal rat liver. However, SSTR1-3 mRNA appeared as HSCs became wholly activated, and could also be identified on the membrane of activated HSCs in the perisinusoid space, fibrous septa, etc. CONCLUSION: The expression of SSTR1-3 in the rat HSC is closely related to its activation. This may reflect one of the main negative regulation mechanisms in the course of HSC activation.
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Cirrose Hepática/etiologia , Fígado/citologia , Receptores de Somatostatina/genética , Animais , Fígado/metabolismo , Masculino , RNA Mensageiro/análise , Ratos , Ratos Sprague-DawleyRESUMO
OBJECTIVE: To investigate the influence of exogenous transforming growth factor beta 1 (TGFbeta1) on growth and signal inhibitor Smad7 protein and its mRNA in BRL cells (rat liver cell line). METHODS: BRL cells were incubated with TGFbeta1 and divided into 0 minute group, 90 minute group and 24 hour group according to the time of incubation with TGFbeta1. Morphologic changes were observed. The expression of Smad7 mRNA and protein was investigated by reverse transcriptase-polymerase chain reaction (RT-PCR), Western blotting, and immnuohistrochemistry. RESULTS: Growth stagnancy and morphologic change of cells was not seen among the three groups. The expression levels of Smad7 mRNA was the highest in 90-minute group and the lowest in 0-minute group, and the 24-hour group took the second place. Most of the Smad7 immune positive granules were observed in cytoplasm. CONCLUSION: TGFbeta1 does not induce growth stagnancy in BRL cells during the period of 90 minutes to 24 hours. There is a relation of effectiveness for a given period of time between the level of Smad7 and TGFbeta1 stimulation.
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Proteínas de Ligação a DNA/biossíntese , Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Transativadores/biossíntese , Fator de Crescimento Transformador beta/farmacologia , Animais , Linhagem Celular , Hepatócitos/metabolismo , Imuno-Histoquímica , RNA Mensageiro/biossíntese , RNA Mensageiro/efeitos dos fármacos , Ratos , Ratos Endogâmicos BUF , Proteína Smad7 , Fator de Crescimento Transformador beta1RESUMO
OBJECTIVE: To examine the expression changes of activin beta A, beta C, beta E and follistatin mRNA in the development of rat hepatic fibrosis induced by carbon tetrachloride (CCl(4)). METHODS: Hepatic fibrosis was induced in rats by subcutaneous injections of 40% carbon tetrachloride oily solution for a period of 1 to 7 weeks. After carbon tetrachloride injection of 1, 2, 3, 4, 5, 6, and 7 weeks, the 6-12 rats were killed every time. The kinetics of activin beta A, beta C, beta E and follistatin mRNA expression were assessed by the semi-quantity RT-PCR. RESULTS: Activin beta A, beta C, beta E and follistatin mRNA could be detected in normal rat livers. After CCl(4) injection for 2 or 3 weeks, beta A mRNA was transiently decreased and became undetectable, then increased gradually. After CCl injection for 6 and 7 weeks, beta A mRNA level was significantly higher than controls (P<0.01). beta C mRNA could be detected after CCl(4) injection for 1 to 4 weeks and was significantly increased after 5 weeks over controls (P<0.05). beta E mRNA could not be detected after CCl(4) injection for 1 to 5 weeks, but significantly increased after CCl(4) injection for 6 or 7 weeks compared with controls (P<0.01). Except for normal rat liver, no follistatin mRNA was detected in rats after CCl(4) injection. CONCLUSIONS: Activins and follistatin have different expression changes in the development of hepatic fibrosis and the imbalance of activins and follistatin expression may involve in the formation of hepatic fibrosis.