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1.
Angew Chem Int Ed Engl ; : e202414493, 2024 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-39245630

RESUMO

The adhesion of H2 bubbles on the electrode surface is one of the main factors limiting the performance of H2 evolution of electrolytic water, especially at high current density. To overcome this problem, here a "quasi-gas phase" electrolytic water reaction system based on capillary effect is proposed for the first time to improve the mass transfer efficiency of H2. The typical feature of this reaction system is that the main site of H2 evolution reaction is transferred from the bulk aqueous solution to the gas phase environment above the bulk aqueous solution, thus effectively inhibiting the aggregation of H2 bubbles and reducing the resistance of their diffusion away. Electrochemical test results show that the proposed quasi-gas phase system can significantly reduce the potential required in H2 evolution reaction process at high current density compared with the conventional electrolytic reaction system. Specifically, the overpotential potential is reduced by 0.31 V when the H2 evolution current density of 250 mA cm-2 is achieved.

2.
Angew Chem Int Ed Engl ; 62(13): e202218717, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36728627

RESUMO

The aqueous electrocatalytic reduction of NO3 - into NH3 (NitrRR) presents a sustainable route applicable to NH3 production and potentially energy storage. However, the NitrRR involves a directly eight-electron transfer process generally required a large overpotential (<-0.2 V versus reversible hydrogen electrode (vs. RHE)) to reach optimal efficiency. Here, inspired by biological nitrate respiration, the NitrRR was separated into two stages along a [2+6]-electron pathway to alleviate the kinetic barrier. The system employed a Cu nanowire catalyst produces NO2 - and NH3 with current efficiencies of 91.5 % and 100 %, respectively at lower overpotentials (>+0.1 vs. RHE). The high efficiency for such a reduction process was further explored in a zinc-nitrate battery. This battery could be specified by a high output voltage of 0.70 V, an average energy density of 566.7 Wh L-1 at 10 mA cm-2 and a power density of 14.1 mW cm-2 , which is well beyond all previously reported similar concepts.

3.
Angew Chem Int Ed Engl ; 62(30): e202305695, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37235524

RESUMO

Redox flow batteries have been discussed as scalable and simple stationary energy storage devices. However, currently developed systems encounter less competitive energy density and high costs, restricting their wider application. There is a lack of appropriate redox chemistry, preferably based on active materials that are abundant in nature and show high solubility in aqueous electrolytes. A nitrogen-centered redox cycle operating between the limiting species ammonia and nitrate via an eight-electron redox reaction stayed practically unnoticed, albeit its ubiquity in biological processes. Ammonia or nitrate are world-scale chemicals with high aqueous solubility, and are then comparably safe. We demonstrate here the successful implementation of such a nitrogen-based redox cycle between ammonia and nitrate with eight-electron transfer as a catholyte for Zn-based flow batteries, which continuously worked for 12.9 days with 930 charging-discharging cycles. A very competitive energy density of 577 Wh L-1 can be reached, which is well above most reported flow batteries (e.g. 8 times the standard Zn-bromide battery), demonstrating that the nitrogen cycle with eight-electron transfer can offer promising cathodic redox chemistry for safe, affordable, and scalable high-energy-density storage devices.

4.
Angew Chem Int Ed Engl ; 61(27): e202203170, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35478427

RESUMO

Direct synthesis of N-containing organic compounds from dinitrogen (N2 ) can make synthetic chemistry more sustainable. Previous bottlenecks in lithium-mediated N2 fixation were resolved by loading Li-metal anodes covered with the typical Li+ ion-conducting solid electrolyte interface, which are subsequently allowed to react with N2 . The developed strategy allowed us to reach high Faradaic efficiencies toward Li3 N. These reactive Li3 N were then contacted with acylchlorides. Surface nitride ions are more nucleophilic than amines which direct the two C-N coupling reactions toward formation of imides rather than amides, and an integrated current efficiency of 57-77 % could be realized. This study thereby not only provides a feasible electrochemical Li3 N synthesis, but also delineates an economical and green synthesis of highly valuable N-containing compounds from N2 under mild conditions, just using commercial spare parts and processes from the omnipresent Li battery technology.

5.
Chemistry ; 25(54): 12464-12485, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31120594

RESUMO

The electrochemical reduction of nitrogen into ammonia under ambient conditions is a potential strategy for sustainable ammonia production. At present, one of the main research directions in the field of electrochemical nitrogen fixation is to improve the current efficiency and ammonia yield by developing efficient nitrogen reduction catalysts. To optimise the selectivity and catalytic activity of nitrogen reduction catalysts more efficiently, herein, we systematically summarise the progress of research on nitrogen reduction catalysts in recent years and present some general catalyst design strategies. Considering that it is difficult for metal-based catalysts to balance the competitive reactions of nitrogen activation and hydrogen evolution, we discuss in detail the advantages and application prospects of non-metallic catalysts in electrochemical nitrogen fixation. Moreover, both the design strategy of surface or interface defects, and how this atomic-level control of functionalisation helps to promote selectivity and catalytic activity are also discussed by theoretical and experimental electrochemistry. On this basis, we also discussed the future development direction, opportunities and challenges of nitrogen reduction electrocatalysts.

6.
Angew Chem Int Ed Engl ; 58(9): 2612-2616, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30560583

RESUMO

Constructing efficient catalysts for the N2 reduction reaction (NRR) is a major challenge for artificial nitrogen fixation under ambient conditions. Herein, inspired by the principle of "like dissolves like", it is demonstrated that a member of the nitrogen family, well-exfoliated few-layer black phosphorus nanosheets (FL-BP NSs), can be used as an efficient nonmetallic catalyst for electrochemical nitrogen reduction. The catalyst can achieve a high ammonia yield of 31.37 µg h-1 mg-1 cat. under ambient conditions. Density functional theory calculations reveal that the active orbital and electrons of zigzag and diff-zigzag type edges of FL-BP NSs enable selective electrocatalysis of N2 to NH3 via an alternating hydrogenation pathway. This work proves the feasibility of using a nonmetallic simple substance as a nitrogen-fixing catalyst and thus opening a new avenue towards the development of more efficient metal-free catalysts.

7.
Zhongguo Zhong Yao Za Zhi ; 43(19): 3905-3912, 2018 Oct.
Artigo em Zh | MEDLINE | ID: mdl-30453717

RESUMO

The aim of this paper was to observe the function of bone marrow mesenchymal stem cell (BMSC) transplantation in process of liver injury induced by carbon tetrachloride (CCl4) in vivo and the intervention effect of Yiguanjian (YGJ), a compound of Chinese herbal medicine. Wistar rats were randomly divided into five groups: normal group, model group, cell transplantation (CT) group, YGJ group and cell transplantation plus Yiguanjian (CTY) group. Liver injury was induced through subcutaneous injection with CCl4 at a dose of 3 mL·kg⁻¹ body weight for 4 weeks, twice a week. They were injected for a total of 9 times. After the first injection with CCl4, rats in the CT group and CTY group were injected with the third-generation BMSCs at dose 1×106 (suspended in 1 mL saline solution) via tail vein. Rats in the YGJ and CTY groups were also intragastrically administered with Yiguanjian once a day. Rat serum ALT and AST activities were increased significantly on the second day after injection with CCl4, while BMSC transplantation and Yiguanjian decreased their activities. After 4 weeks of injection with CCl4, serum ALT, AST and γ-GT activities, and serum TNF-α and IL-6 expressions were increased, while TBIL were decreased in model rats compared with normal rats. Meanwhile, liver cells edema, plasmatic loose, and numerous lipid droplets were observed in rats of the model group. BMSC transplantation aggravated liver injury compared with model rats, which was manifested by decreasing SOD activity, increased MDA, TG, TNF-α and IL-6 levels, and aggravated necrosis level of hepatocytes, fusion of lipid droplets, and collagen deposition in liver tissue. Yiguanjian decreased liver injury induced by CCl4 alone and CCl4 plus BMSC transplantation. SRY gene in situ hybridization method was used to detect the positive SRY expressions in heart, liver, spleen, lung and kidney, especially in liver, while Yiguangjian decreased liver SRY expression. Wnt and ß-catenin showed high expressions in rats of normal group, which were decreased significantly in rats of models group, while Yiguanjian increased their expressions. In conclusion, BMSC transplantation could exacerbate liver injury, while Yiguanjian could protect liver injury induced by CCl4 and BMSC transplantation, which was related to decreasing the homing of BMSCs to liver and up-regulating Wnt/ß-catenin signaling pathway.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/terapia , Medicamentos de Ervas Chinesas/farmacologia , Cirrose Hepática Experimental/terapia , Transplante de Células-Tronco Mesenquimais , Animais , Medula Óssea , Tetracloreto de Carbono , Fígado , Ratos , Ratos Wistar , Via de Sinalização Wnt
8.
J Am Chem Soc ; 139(29): 9771-9774, 2017 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-28693318

RESUMO

We report the discovery of a dramatically enhanced N2 electroreduction reaction (NRR) selectivity under ambient conditions via the Li+ incorporation into poly(N-ethyl-benzene-1,2,4,5-tetracarboxylic diimide) (PEBCD) as a catalyst. The detailed electrochemical evaluation and density functional theory calculations showed that Li+ association with the O atoms in the PEBCD matrix can retard the HER process and can facilitate the adsorption of N2 to afford a high potential scope for the NRR process to proceed in the "[O-Li+]·N2-Hx" alternating hydrogenation mode. This atomic-scale incorporation strategy provides new insight into the rational design of NRR catalysts with higher selectivity.

9.
Chemistry ; 21(12): 4614-21, 2015 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-25572117

RESUMO

Three-dimensional (3D) nanometal films serving as current collectors have attracted much interest recently owing to their promising application in high-performance supercapacitors. In the process of the electrochemical reaction, the 3D structure can provide a short diffusion path for fast ion transport, and the highly conductive nanometal may serve as a backbone for facile electron transfer. In this work, a novel polypyrrole (PPy) shell@3D-Ni-core composite is developed to enhance the electrochemical performance of conventional PPy. With the introduction of a Ni metal core, the as-prepared material exhibits a high specific capacitance (726 F g(-1) at a charge/discharge rate of 1 A g(-1)), good rate capability (a decay of 33% in Csp with charge/discharge rates increasing from 1 to 20 A g(-1)), and high cycle stability (only a small decrease of 4.2% in Csp after 1000 cycles at a scan rate of 100 mV s(-1)). Furthermore, an aqueous symmetric supercapacitor device is fabricated by using the as-prepared composite as electrodes; the device demonstrates a high energy density (≈21.2 Wh kg(-1)) and superior long-term cycle ability (only 4.4% and 18.6% loss in Csp after 2000 and 5000 cycles, respectively).

10.
Zhongguo Zhong Yao Za Zhi ; 40(12): 2383-8, 2015 Jun.
Artigo em Zh | MEDLINE | ID: mdl-26591530

RESUMO

To observe the effect of calycosin on the proliferation and activation of primary hepatic stellate cells (HSCs) in rats, and prove calycosin shows the effects through peroxisome proliferator-activated receptor γ(PPARγ) and farnesoid X receptor (FXR). The results indicated that calycosin could inhibit HSC proliferation and expressions of activation marker smooth muscle actin-α and type I collagen. With the increase in HSC activation time, FXR expression reduced, but with no notable impact from calycosin. Calycosin could up-regulate PPARγ expression and its nuclear transition in a concentration-dependent manner. Its prohibitory effect on HSC activation could be blocked by PPARγ antagonist. In conclusion, calycosin could inhibit HSC activation and proliferation, which may be related with the up-regulation of PPARγ signal pathway.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Células Estreladas do Fígado/efeitos dos fármacos , Isoflavonas/farmacologia , PPAR gama/genética , Regulação para Cima/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células Estreladas do Fígado/citologia , Células Estreladas do Fígado/metabolismo , Masculino , PPAR gama/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo
11.
Zhonghua Gan Zang Bing Za Zhi ; 22(2): 113-7, 2014 Feb.
Artigo em Zh | MEDLINE | ID: mdl-24735593

RESUMO

OBJECTIVE: To assess the performance of FibroScan in evaluating the curative effects of traditional Chinese medicine (TCM) on liver fibrosis, and to analyze factors influencing the diagnostic accuracy. METHODS: Data of FibroScan values, types of disease, use of drug, liver function indexes, prothrombin time (PT) and international normalized ratio (INR) were collected at both pre- (1 month prior) and post-FibroScan for 102 patients who underwent at least two FibroScan procedures. Patients were subgrouped according to presence of fibrosis, presence of cirrhosis, and TCM formulation and statistically analyzed. RESULTS: The pre- and post-FibroScan mean liver stiffness measurements (LSMs) were significantly different when the variation of LSM was more than or equal to2 kPa for the non-fibrotic group (vs. the fibrotic group), or when the variation wasmore than or equal to4 kPa for the cirrhotic group (vs. the non-cirrhotic group). In addition, the three TCM formulation groups showed significant differences, with the most robust difference exhibited between the FuZheng HuaYu formulation group and the other treatment groups (P = 0.010). No significant differences were observed for the liver function indexes, PT, or INR. However, the post-FibroScan levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyltransferase (GGT) was significantly reduced in patients with reduced LSM. CONCLUSION: FibroScan may be a useful non-invasive clinical tool for evaluating the comprehensive curative effect of treatments for chronic liver diseases, and its performance is not obviously impacted by ALT, AST, GGT, PT, and INR. The criteria for efficacy established by FibroScan are 2 kPa for the patients without liver fibrosis and 4 kPa for patients with liver cirrhosis.

12.
Nat Commun ; 14(1): 5668, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37704640

RESUMO

For decarbonization of ammonia production in industry, alternative methods by exploiting renewable energy sources have recently been explored. Nonetheless, they still lack yield and efficiency to be industrially relevant. Here, we demonstrate an advanced approach of nitrogen fixation to synthesize ammonia at ambient conditions via laser-induced multiphoton dissociation of lithium oxide. Lithium oxide is dissociated under non-equilibrium multiphoton absorption and high temperatures under focused infrared light, and the generated zero-valent metal spontaneously fixes nitrogen and forms a lithium nitride, which upon subsequent hydrolysis generates ammonia. The highest ammonia yield rate of 30.9 micromoles per second per square centimeter is achieved at 25 °C and 1.0 bar nitrogen. This is two orders of magnitude higher than state-of-the-art ammonia synthesis at ambient conditions. The focused infrared light here is produced by a commercial simple CO2 laser, serving as a demonstration of potentially solar pumped lasers for nitrogen fixation and other high excitation chemistry. We anticipate such laser-involved technology will bring unprecedented opportunities to realize not only local ammonia production but also other new chemistries .

13.
Stem Cell Res Ther ; 14(1): 45, 2023 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-36941658

RESUMO

BACKGROUND: Cholestatic liver fibrosis (CLF) is caused by inflammatory destruction of the intrahepatic bile duct and abnormal proliferation of the small bile duct after cholestasis. Activation of the Notch signaling pathway is required for hepatic stem cells to differentiate into cholangiocytes during the pathogenesis of CLF. Our previous research found that the expression of the Numb protein, a negative regulator of Notch signaling, was significantly reduced in the livers of patients with primary biliary cholangitis and CLF rats. However, the relationship between the Numb gene and CLF is largely unclear. In this study, we investigated the role of the Numb gene in the treatment of bile duct ligation (BDL)-induced CLF. METHODS: In vivo, bone marrow-derived mesenchymal stem cells (BM-MSCs) with Numb gene overexpression or knockdown obtained using lentivirus transfection were transplanted into the livers of rats with BDL-induced CLF. The effects of the Numb gene on stem cell differentiation and CLF were evaluated by performing histology, tests of liver function, and measurements of liver hydroxyproline, cytokine gene and protein levels. In vitro, the Numb gene was overexpressed or knocked down in the WB-F344 cell line by lentivirus transfection, Then, cells were subjected immunofluorescence staining and the detection of mRNA levels of related factors, which provided further evidence supporting the results from in vivo experiments. RESULTS: BM-MSCs overexpressing the Numb gene differentiated into hepatocytes, thereby inhibiting CLF progression. Conversely, BM-MSCs with Numb knockdown differentiated into biliary epithelial cells (BECs), thereby promoting the ductular reaction (DR) and the progression of CLF. In addition, we confirmed that knockdown of Numb in sodium butyrate-treated WB-F344 cells aggravated WB-F344 cell differentiation into BECs, while overexpression of Numb inhibited this process. CONCLUSIONS: The transplantation of BM-MSCs overexpressing Numb may be a useful new treatment strategy for CLF.


Assuntos
Colestase , Células-Tronco Mesenquimais , Ratos , Animais , Ratos Endogâmicos F344 , Cirrose Hepática/genética , Cirrose Hepática/terapia , Colestase/genética , Colestase/terapia , Colestase/complicações , Fígado/metabolismo , Células-Tronco Mesenquimais/patologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo
14.
Chin J Integr Med ; 29(4): 316-324, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34816365

RESUMO

OBJECTIVE: To observe the effect of amygdalin on liver fibrosis in a liver fibrosis mouse model, and the underlying mechanisms were partly dissected in vivo and in vitro. METHODS: Thirty-two male mice were randomly divided into 4 groups, including control, model, low- and high-dose amygdalin-treated groups, 8 mice in each group. Except the control group, mice in the other groups were injected intraperitoneally with 10% carbon tetrachloride (CCl4)-olive oil solution 3 times a week for 6 weeks to induce liver fibrosis. At the first 3 weeks, amygdalin (1.35 and 2.7 mg/kg body weight) were administered by gavage once a day. Mice in the control group received equal quantities of subcutaneous olive oil and intragastric water from the fourth week. At the end of 6 weeks, liver tissue samples were harvested to detect the content of hydroxyproline (Hyp). Hematoxylin and eosin and Sirius red staining were used to observe the inflammation and fibrosis of liver tissue. The expressions of collagen I (Col-I), alpha-smooth muscle actin (α-SMA), CD31 and transforming growth factor ß (TGF-ß)/Smad signaling pathway were observed by immunohistochemistry, quantitative real-time polymerase chain reaction and Western blot, respectively. The activation models of hepatic stellate cells, JS-1 and LX-2 cells induced by TGF-ß1 were used in vitro with or without different concentrations of amygdalin (0.1, 1, 10 µmol/L). LSECs. The effect of different concentrations of amygdalin on the expressions of liver sinusoidal endothelial cells (LSECs) dedifferentiation markers CD31 and CD44 were observed. RESULTS: High-dose of amygdalin significantly reduced the Hyp content and percentage of collagen positive area, and decreased the mRNA and protein expressions of Col-I, α-SMA, CD31 and p-Smad2/3 in liver tissues of mice compared to the model group (P<0.01). Amygdalin down-regulated the expressions of Col-I and α-SMA in JS-1 and LX-2 cells, and TGFß R1, TGFß R2 and p-Smad2/3 in LX-2 cells compared to the model group (P<0.05 or P<0.01). Moreover, 1 and 10 µmol/L amygdalin inhibited the mRNA and protein expressions of CD31 in LSECs and increased CD44 expression compared to the model group (P<0.05 or P<0.01). CONCLUSIONS: Amygdalin can dramatically alleviate liver fibrosis induced by CCl4 in mice and inhibit TGF-ß/Smad signaling pathway, consequently suppressing HSCs activation and LSECs dedifferentiation to improve angiogenesis.


Assuntos
Amigdalina , Fator de Crescimento Transformador beta , Ratos , Masculino , Camundongos , Animais , Fator de Crescimento Transformador beta/metabolismo , Amigdalina/farmacologia , Amigdalina/uso terapêutico , Células Endoteliais/metabolismo , Azeite de Oliva/metabolismo , Azeite de Oliva/farmacologia , Azeite de Oliva/uso terapêutico , Ratos Wistar , Proteínas Smad/metabolismo , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Fígado , Fator de Crescimento Transformador beta1/metabolismo , Transdução de Sinais , Colágeno Tipo I/metabolismo , Tetracloreto de Carbono , Células Estreladas do Fígado
15.
BMC Complement Altern Med ; 12: 33, 2012 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-22471627

RESUMO

BACKGROUND: Huangqi decoction was first described in Prescriptions of the Bureau of Taiping People's Welfare Pharmacy in Song Dynasty (AD 1078), and it is an effective recipe that is usually used to treat consumptive disease, anorexia, and chronic liver diseases. Transforming growth factor beta 1 (TGFß1) plays a key role in the progression of liver fibrosis, and Huangqi decoction and its ingredients (IHQD) markedly ameliorated hepatic fibrotic lesions induced by ligation of the common bile duct (BDL). However, the mechanism of IHQD on hepatic fibrotic lesions is not yet clear. The purpose of the present study is to elucidate the roles of TGFß1 activation, Smad-signaling pathway, and extracellular signal-regulated kinase (ERK) in the pathogenesis of biliary fibrosis progression and the antifibrotic mechanism of IHQD. METHODS: A liver fibrosis model was induced by ligation of the common bile duct (BDL) in rats. Sham-operation was performed in control rats. The BDL rats were randomly divided into two groups: the BDL group and the IHQD group. IHQD was administrated intragastrically for 4 weeks. At the end of the fifth week after BDL, animals were sacrificed for sampling of blood serum and liver tissue. The effect of IHQD on the TGFß1 signaling pathway was evaluated by western blotting and laser confocal microscopy. RESULTS: Decreased content of hepatic hydroxyproline and improved liver function and histopathology were observed in IHQD rats. Hepatocytes, cholangiocytes, and myofibroblasts in the cholestatic liver injury released TGFß1, and activated TGFß1 receptors can accelerate liver fibrosis. IHQD markedly inhibited the protein expression of TGFß1, TGFß1 receptors, Smad3, and p-ERK1/2 expression with no change of Smad7 expression. CONCLUSION: IHQD exert significant therapeutic effects on BDL-induced fibrosis in rats through inhibition of the activation of TGFß1-Smad3 and TGFß1-ERK1/2 signaling pathways.


Assuntos
Doenças Biliares/tratamento farmacológico , Ducto Colédoco/efeitos dos fármacos , Medicamentos de Ervas Chinesas/uso terapêutico , Hepatopatias/tratamento farmacológico , Fígado/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Astrágalo , Astragalus propinquus , Doenças Biliares/metabolismo , Doenças Biliares/patologia , Ducto Colédoco/metabolismo , Ducto Colédoco/patologia , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fibrose/tratamento farmacológico , Ligadura , Fígado/citologia , Fígado/metabolismo , Fígado/patologia , Hepatopatias/metabolismo , Hepatopatias/patologia , Masculino , Fitoterapia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Receptor do Fator de Crescimento Transformador beta Tipo I , Transdução de Sinais/efeitos dos fármacos , Proteína Smad3/metabolismo
16.
Zhong Xi Yi Jie He Xue Bao ; 10(12): 1405-12, 2012 Dec.
Artigo em Zh | MEDLINE | ID: mdl-23257134

RESUMO

OBJECTIVE: To investigate the effects of three classical anti-jaundice formulas Yinchenhao Decoction (YCHD). Yinchen Wuling San (YCWLS) and Zhizi Baipi Decoction (ZZBPD) on liver fibrosis induced by dimethylnitrosamine (DMN) in rats and explore the formula-syndrome relationship. METHODS: Forty-eight rats were weighted, and divided into five groups: normal control, DMN, YCHD, YCWLS and ZZBPD groups using stratified random method. Liver fibrosis in rats was induced by intraperitoneal injection of DMN for 4 weeks at the dosage 10 mg/kg body weight, once per day for 3 consecutive days in each week. Each groups was gavaged with distilled water (control or model group), YCHD, YCWLS and ZZBPD respectively in the last 2-week modeling period. At the end of the 4th week, rats were sacrificed and their blood sample and liver tissue were taken for detecting pathology and analyzing of hydroxyproline (Hyp) and liver function. RESULTS: Compared with the normal control group, DMN model group showed liver damage and liver fibrosis with remarkably increased Hyp content (P<0.01) and abnormal liver function (P<0.01). Liver fibrosis induced by DMN in rats was improved by administration of YCHD. Compared with DMN model group, content of Hyp was decreased remarkably (P<0.01) and liver function and hepatic histology were improved significantly after 2 weeks of YCHD treatment (P<0.05 or P<0.01)., and content of hepatic Hyp was decreased in the ZZBPD groups. Comparison of various parameters between groups showed that content of serum total bilirubin was decreased significantly in the YCWLS group (P<0.01), and content of hepatic Hyp was decreased in the ZZBPD group. CONCLUSION: Efficacy of YCHD in inhibition of liver fibrosis induced by DMN in rats is far better than YCWLS and ZZBPD. The pathogenesis of the liver fibrosis induced by DMN is mainly damp-heat. In addition, both damp and heat pathogenic factors play very important role in this model. The syndrome is highly correlated with the prescription YCHD.


Assuntos
Dimetilnitrosamina/efeitos adversos , Medicamentos de Ervas Chinesas/uso terapêutico , Cirrose Hepática Experimental/induzido quimicamente , Cirrose Hepática Experimental/tratamento farmacológico , Fitoterapia , Animais , Hidroxiprolina/análise , Fígado/patologia , Cirrose Hepática Experimental/patologia , Masculino , Ratos , Ratos Wistar
17.
Zhong Xi Yi Jie He Xue Bao ; 10(11): 1286-92, 2012 Nov.
Artigo em Zh | MEDLINE | ID: mdl-23158948

RESUMO

OBJECTIVE: To explore the intervention effects of Xiaopi Pill (XPW), a compound traditional Chinese herbal medicine, on the development progress of dimethylnitrosamine (DMN)-induced liver fibrosis in rats. METHODS: Liver fibrosis model was established by intraperitoneal injection of 0.5% DMN 2 mL/kg thrice a week for 4 weeks. Rats were divided into control group given saline and treatment group given XPW during the 3rd week of DMN injections. Rats were sacrificed at the end of the experiment, and then liver histological changes, liver function and mRNA expression of the liver fibrosis-associated markers were observed. RESULTS: (1) At the end of the 2nd and 4th weeks of DMN injection, serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) increased significantly in rats (P<0.01 or P<0.05); content of total bilirubin (TBil) increased significantly compared with the normal group until the end of the 4th week (P<0.05); compared with the model group after 4 weeks of DMN injection, the serum levels of ALT, AST, ALP and TBil were decreased remarkably in the XPW-treated group (P<0.01 or P<0.05). (2) The hepatic inflammation and collagen deposition in hepatic tissues increased by different degrees in experimental rats. Parts of pathological changes in the rat liver were found at the end of the 4th week, including a complete round structure of false flocculus round, meantime, the hydroxyproline content of hepatic tissue was increased significantly at the end of the 2nd and 4th weeks (P<0.05). Compared with the 4-week model group, the hepatic inflammation, collagen deposition and hydroxyproline content in hepatic tissues were alleviated dramatically (P<0.05). (3) Compared with the normal and 2nd week groups, protein expression of alpha-smooth muscle actin (α-SMA) was gradually increased, and that of the 4th week group were aggrandized significantly (P<0.01). Compared with the normal group, the mRNA expression of α-SMA, transforming growth factor-ß1 (TGF-ß1), tissue inhibitor of metalloproteinase-1 (TIMP-1), and heme oxygenase-1 (HO-1) was gradually increased. Further changes in above-mentioned abnormalities were found in the model rats at the end of the 4th week (P<0.01); while compared to the 4th week group, protein and mRNA levels of α-SMA and mRNA levels of TGF-ß1, TIMP-1, and HO-1 were decreased significantly in the XPW group (P<0.01 or P<0.05). CONCLUSION: Progressive DMN-induced liver fibrosis in rats can be suppressed by XPW; the mechanism may be associated with inhibition of the activated hepatic stellate cells.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Cirrose Hepática Experimental/patologia , Fígado/patologia , Animais , Dimetilnitrosamina/efeitos adversos , Medicamentos de Ervas Chinesas/uso terapêutico , Hidroxiprolina/metabolismo , Fígado/metabolismo , Cirrose Hepática Experimental/induzido quimicamente , Cirrose Hepática Experimental/metabolismo , Masculino , Ratos , Ratos Wistar
18.
J Ethnopharmacol ; 292: 115224, 2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35351577

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Triptolide (TP) exhibits extensive pharmacological activity, but its hepatotoxicity and intestinal injury are significant and limit its clinical use. AIM OF THE STUDY: To investigate the effect of gut microbiota disturbance after antibiotic pretreatment on TP-induced hepatotoxicity, intestinal injury and their mechanism. MATERIALS AND METHODS: We compared the characteristics of TP-induced hepatotoxicity and intestinal injury in mice with or without antibiotic pretreatment. The levels of cytokines in the serum, immunohistochemistry, and the pharmacokinetics of TP were determined. RESULT: Antibiotic pretreatment aggravates TP-induced hepatotoxicity and ileum/colon injury. TP induces hepatotoxicity in a dose-dependent manner after antibiotic pretreatment. Serum IL-1ß and IL-6 levels were increased in mice given oral TP after antibiotic pretreatment. TP can increase the expression of NLRP3 inflammasome in hepatocytes, and Oral TP after antibiotic pretreatment can significantly enhance its expression, but NLRP3 inflammasome no significant change in colon and ileum. The pharmacokinetic characteristics of TP are altered significantly by antibiotic pretreatment, as shown by a 145.87% increase in Cmax, a 155.11% increase in AUC0-t, a 155.1% increase in relative bioavailability, and a 15.44% delay in MRT. Moreover, TP causes hepatotoxicity in a time-dependent manner. CONCLUSIONS: Antibiotic pretreatment aggravates triptolide-induced hepatotoxicity and intestinal injury through elevated inflammatory response and promoted triptolide absorption.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Diterpenos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Fenantrenos , Animais , Antibacterianos/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Diterpenos/farmacologia , Compostos de Epóxi , Inflamassomos/metabolismo , Fígado , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Fenantrenos/toxicidade
19.
Cancer Lett ; 526: 259-272, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34863886

RESUMO

EBV-encoded circular RNA LMP2A (ebv-circLMP2A) was found to be expressed in EBV-associated gastric carcinoma (EBVaGC) and associated with distant metastasis and poor prognosis. Angiogenesis is a key step in tumor invasion and metastasis and plays a crucial role in tumor progression. However, it is unclear whether and how ebv-circLMP2A is involved in angiogenesis. In this study, we showed that MVD, HIF1α, and VEGFA expression was increased in EBVaGC mouse xenografts with high expression of ebv-circLMP2A. The expression of ebv-circLMP2A was positively correlated with MVD, HIF1α, and VEGFA expression in clinical samples of EBVaGC. Knockdown of ebv-circLMP2A repressed tube formation and migration of HUVECs and decreased VEGFA and HIF1α expression in cancer cells under hypoxia, while ectopic expression of ebv-circLMP2A reversed these effects. Additionally, knockdown of HIF1α blocked the upregulation of ebv-circLMP2A by hypoxia, and ebv-circLMP2A interacted with KHSRP to enhance KHSRP-mediated decay of VHL mRNA, leading to the accumulation of HIF1α under hypoxia. There was a positive feedback loop between HIF1α and ebv-circLMP2A that promotes angiogenesis under hypoxia. ebv-circLMP2A was essential in regulating tumor angiogenesis in EBVaGC and might provide a valuable therapeutic target for EBVaGC.


Assuntos
Hipóxia Celular/genética , Proteínas de Ligação a RNA/metabolismo , Neoplasias Gástricas/genética , Transativadores/metabolismo , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo , Animais , Humanos , Camundongos , Neovascularização Patológica , Neoplasias Gástricas/patologia , Fator A de Crescimento do Endotélio Vascular
20.
Front Pharmacol ; 13: 1016552, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36313366

RESUMO

Liver fibrosis is a common pathological process of all chronic liver diseases. Hepatic stellate cells (HSCs) play a central role in the development of liver fibrosis. Cyclin-dependent kinase 9 (CDK9) is a cell cycle kinase that regulates mRNA transcription and elongation. A CDK9 inhibitor SNS-032 has been reported to have good effects in anti-tumor. However, the role of SNS-032 in the development of liver fibrosis is unclear. In this study, SNS-032 was found to alleviate hepatic fibrosis by inhibiting the activation and inducing the apoptosis of active HSCs in carbon tetrachloride-induced model mice. In vitro, SNS-032 inhibited the activation and proliferation of active HSCs and induced the apoptosis of active HSCs by downregulating the expression of CDK9 and its downstream signal transductors, such phosphorylated RNA polymerase II and Bcl-2. CDK9 short hairpin RNA was transfected into active HSCs to further elucidate the mechanism of the above effects. Similar results were observed in active HSCs after CDK9 knockdown. In active HSCs with CDK9 knockdown, the expression levels of CDK9, phosphorylated RNA polymerase II, XIAP, Bcl-2, Mcl-1, and ɑ-SMA significantly decreased, whereas those of cleaved-PARP1 and Bax decreased prominently. These results indicated that SNS-032 is a potential drug and CDK9 might be a new prospective target for the treatment of liver fibrosis.

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