RESUMEN
Liver fibrosis is a wound-healing process characterized by excess formation of extracellular matrix (ECM) from activated hepatic stellate cells (HSCs). Previous studies show that both EZH2, an epigenetic regulator that catalyzes lysine 27 trimethylation on histone 3 (H3K27me3), and long non-coding RNA H19 are highly correlated with fibrogenesis. In the current study, we investigated the underlying mechanisms. Various models of liver fibrosis including Mdr2-/-, bile duct ligation (BDL) and CCl4 mice were adapted. We found that EZH2 was markedly upregulated and correlated with H19 and fibrotic markers expression in these models. Administration of EZH2 inhibitor 3-DZNeP caused significant protective effects in these models. Furthermore, treatment with 3-DZNeP or GSK126 significantly inhibited primary HSC activation and proliferation in TGF-ß-treated HSCs and H19-overexpreesing LX2 cells in vivo. Using RNA-pull down assay combined with RNA immunoprecipitation, we demonstrated that H19 could directly bind to EZH2. Integrated analysis of RNA-sequencing (RNA-seq) and chromatin immunoprecipitation sequencing (ChIP-seq) further revealed that H19 regulated the reprogramming of EZH2-mediated H3K27me3 profiles, which epigenetically promoted several pathways favoring HSCs activation and proliferation, including epithelial-mesenchymal transition and Wnt/ß-catenin signaling. In conclusion, highly expressed H19 in chronic liver diseases promotes fibrogenesis by reprogramming EZH2-mediated epigenetic regulation of HSCs activation. Targeting the H19-EZH2 interaction may serve as a novel therapeutic approach for liver fibrosis.
Asunto(s)
Proteína Potenciadora del Homólogo Zeste 2 , Histonas , Cirrosis Hepática , ARN Largo no Codificante , Animales , Ratones , Epigénesis Genética , Células Estrelladas Hepáticas/metabolismo , Histonas/metabolismo , Hígado/metabolismo , Cirrosis Hepática/genética , Cirrosis Hepática/metabolismo , Lisina/química , Lisina/metabolismo , Metilación , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Proteína Potenciadora del Homólogo Zeste 2/genética , Proteína Potenciadora del Homólogo Zeste 2/metabolismoRESUMEN
Obesity contributes to the progression of various chronic diseases, and shortens life expectancy. With abundant mitochondria, brown adipose tissue (BAT) dissipates energy through heat to limit weight gain and metabolic dysfunction in obesity. Our previous studies have shown that aurantio-obtusin (AO), a bioactive ingredient in Chinese traditional medicine Cassiae semen significantly improves hepatic lipid metabolism in a steatotic mouse model. In the current study we investigated the effects of AO on lipid metabolism in the BAT of diet-induced obesity mice and in oleic acid and palmitic acid (OAPA)-stimulated primary mature BAT adipocytes. Obese mice were established by feeding a HFHS diet for 4 weeks, and then administered AO (10 mg/kg, i.g.) for another 4 weeks. We showed that AO administration significantly increased the weight of BAT and accelerated energy expenditure to protect the weight increase in the obese mice. Using RNA sequencing and molecular biology analysis we found that AO significantly enhanced mitochondrial metabolism and UCP1 expression by activating PPARα both in vivo and in vitro in the primary BAT adipocytes. Interestingly, AO administration did not improve metabolic dysfunction in the liver and white adipose tissue of obese mice after interscapular BAT excision. We demonstrated that low temperature, a trigger of BAT thermogenesis, was not a decisive factor for AO to stimulate the growth and activation of BATs. This study uncovers a regulatory network of AO in activating BAT-dependent lipid consumption and brings up a new avenue for the pharmaceutical intervention in obesity and related comorbidities.
Asunto(s)
Tejido Adiposo Pardo , PPAR alfa , Ratones , Animales , Tejido Adiposo Pardo/metabolismo , PPAR alfa/metabolismo , Ratones Obesos , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Mitocondrias/metabolismo , Metabolismo Energético , Tejido Adiposo Blanco/metabolismo , Termogénesis , Ratones Endogámicos C57BLRESUMEN
Liver fibrosis is the common consequence of almost all liver diseases and has become an urgent clinical problem without efficient therapies. Recent evidence has shown that hepatocytes-derived extracellular vesicles (EVs) play important roles in liver pathophysiology, but little is known about the role of damaged hepatocytes-derived EVs in hepatic stellate cell (HSC) activation and following fibrosis. Tetramethylpyrazine (TMP) from Ligusticum wallichii Franchat exhibits a broad spectrum of biological activities including liver protection. In this study, we investigated whether TMP exerted liver-protective action through regulating EV-dependent intercellular communication between hepatocytes and HSCs. Chronic liver injury was induced in mice by CCl4 (1.6 mg/kg, i.g.) twice a week for 8 weeks. In the last 4 weeks of CCl4 administration, mice were given TMP (40, 80, 160 mg·kg-1·d-1, i.g.). Acute liver injury was induced in mice by injection of a single dose of CCl4 (0.8 mg/kg, i.p.). After injection, mice were treated with TMP (80 mg/kg) every 24 h. We showed that TMP treatment dramatically ameliorated CCl4-induced oxidative stress and hepatic inflammation as well as acute or chronic liver fibrosis. In cultured mouse primary hepatocytes (MPHs), treatment with CCl4 or acetaminophen resulted in mitochondrial dysfunction, release of mitochondrial DNA (mtDNA) from injured hepatocytes to adjacent hepatocytes and HSCs through EVs, mediating hepatocyte damage and fibrogenic responses in activated HSCs; pretreatment of MPHs with TMP (25 µM) prevented all these pathological effects. Transplanted serum EVs from TMP-treated mice prevented both initiation and progression of liver fibrosis caused by CCl4. Taken together, this study unravels the complex mechanisms underlying the protective effects of TMP against mtDNA-containing EV-mediated hepatocyte injury and HSC activation during liver injury, and provides critical evidence inspiring the development of TMP-based innovative therapeutic agents for the treatment of liver fibrosis.
Asunto(s)
Vesículas Extracelulares , Hepatopatías , Animales , Tetracloruro de Carbono/efectos adversos , Tetracloruro de Carbono/metabolismo , ADN Mitocondrial/metabolismo , ADN Mitocondrial/farmacología , ADN Mitocondrial/uso terapéutico , Fibrosis , Células Estrelladas Hepáticas , Hepatocitos , Hígado/metabolismo , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/prevención & control , Hepatopatías/metabolismo , Ratones , Mitocondrias/patología , PirazinasRESUMEN
Angelicae Sinensis Radix (Danggui) and Ligusticum Chuanxiong Rhizoma (Chuan Xiong) herb-pair (DC) have been frequently used in Traditional Chinese medicine (TCM) prescriptions for hundreds of years to prevent vascular diseases and alleviate pain. However, the mechanism of DC herb-pair in the prevention of liver fibrosis development was still unclear. In the present study, the effects and mechanisms of DC herb-pair on liver fibrosis were examined using network pharmacology and mouse fibrotic model. Based on the network pharmacological analysis of 13 bioactive ingredients found in DC, a total of 46 targets and 71 pathways related to anti-fibrosis effects were obtained, which was associated with mitogen-activated protein kinase (MAPK) signal pathway, hepatic inflammation and fibrotic response. Furthermore, this hypothesis was verified using carbon tetrachloride (CCl4)-induced fibrosis model. Measurement of liver functional enzyme activities and histopathological examination showed that DC dramatically reduced bile acid levels, inflammatory cell infiltration and collagen deposition caused by CCl4. The increased expression of liver fibrosis markers, such as collagen 1, fibronectin, α-smooth muscle actin (α-SMA) and transforming growth factor-ß (TGF-ß), and inflammatory factors, such as chemokine (C-C motif) ligand 2 (MCP-1), interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α) and IL-6 in fibrotic mice were significantly downregulated by DC herb-pair through regulation of extracellular signal-regulated kinase 1/2 (ERK1/2)-protein kinase B (AKT) signaling pathways. Collectively, these results suggest that DC prevents the development of liver fibrosis by inhibiting collagen deposition, decreasing inflammatory reactions and bile acid accumulation, which provides insights into the mechanisms of herb-pair in improving liver fibrosis.
Asunto(s)
Medicamentos Herbarios Chinos , Ligusticum , Cirrosis Hepática , Angelica sinensis , Animales , Medicamentos Herbarios Chinos/farmacología , Ligusticum/química , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/prevención & control , Medicina Tradicional China , Ratones , Rizoma/químicaRESUMEN
The disposal of construction and demolition (C&D) waste has become a serious problem in China due to the rapid increase of Chinese construction industry in recent years. In the present study, typical C&D waste was employed for ceramsite fabrication so as to find a new way for its effective recycling. A novel process was developed for manufacturing high-quality porous ceramsite according to the special chemical composition and properties of C&D waste. Most importantly, a unique bloating agent was developed for the porous structure formation since it was difficult to obtain a suitable porous structure using traditional bloating agents. The effects of processing parameters such as sintering temperature, heating rate and soaking time were investigated, and the bloating mechanism for ceramsite was discussed. The C&D waste ceramsite (CDWC), with high-intensity, low density and homogeneous mechanical properties, was much more suitable for application in the construction field. This study provides a practical process for efficient recycling of the rapidly increasing quantities of C&D waste.
Asunto(s)
Materiales de Construcción , Residuos Industriales , Reciclaje/métodos , Silicatos de Aluminio , Arcilla , Metales Pesados , Porosidad , TemperaturaRESUMEN
In recent years, inductively coupled plasma atomic emission spectrometry (ICP-AES) have been commonly used to determine the soil available K and Na with the extraction solution of HCl-H2SO4, while previous data of soil available K and Na were measured by flame atomic absorption spectrometry (FAAS) with the extraction solution of NH4OAc. In order to utilize previous data, quest for the convertibility of the data determined by ICP-AES and FAAS, and compare the data determined by both methods, the authors chose four types of soil to determine soil available K and Na by ICP-AES and FAAS, respectively. Four types of soil represent grit soil, clay, silt from river and silt from sea, respectively. Soil samples included four types of soil and these samples represent different soil nutrition. The authors analyzed the correlations of two kinds of measured data. The paired samples t-test proves that there was significantly positively correlation between these two methods. The correlation coefficient of the data between these two methods for measuring soil available K is 0.98. The results of soil available K determined by the two methods can be conversed through the formula, y = l.14x + 6.53 (R2 = 0.91, n=24, p < 0.001). As for Na, although there is a significantly positively correlation between these two methods, the slopes of single model of clay and grit soil were different from that of general model. And so the results determined by the two methods can be conversed through different formula according to the types of soil, that is, for clay: y = l.23x + 10.03; for grit soil: y = 3.12x - 23.03; for silt: y = 0.60x. In conclusion, the authors' results showed that previous data of available K and Na measured by FAAS with the extraction solution of NH4OAc were available. And these data were comparable to the data measured by ICP-AES through definite formula The authors' results also suggested that ICP-AES was preferable when many elements were measured at the same time. Under this condition, ICP-AES was economical, efficient and reliable.
RESUMEN
This paper reports the determination of three nitrogen states in plants: nitric nitrogen, ammoniacal nitrogen and total nitrogen. The plant sample was digested by the Kjeldathl method with H2SO4 + H2O2. The solution of the sample was determined by three methods: absorption photometric method, indigotic colorimetry, and UV absorption photometric method after K2S2O8 oxidation. By comparing the results, the relationship among the three N states is that the total N = NH4+ + NO3-. Suitable methods were found for the determination of the elements, thus providing a scientific basis for the selection of suitable methods for chemical element analysis in plants.