Issues on carcinogen contaminated antihypertensive drugs and constructing drug safety management system

European Medicines Agency withdrew valsartan from European market in July 2018 because it was contaminated with carcinogen, N-nitrosodimethylamine (NDMA) and N-nitrosodiethylamine (NDEA). Medicines and Healthcare Products Regulatory Agency also found the same contamination and withdrew it from England market. US Food and Drug Administration followed the action after confirming its contamination. Ministry of Food and Drug Safety (MFDS) conducted testing all the valsartans at Korean market and withdrew some of them from market after confirming the contamination with NDMA. MFDS provided the pharmaceutical companies and laboratory institutions with the manual for testing both NDMA and NDEA and educated relevant personnels. MFDS also evaluated the health impact of the contaminated valsartan on the hypertensive patients who took the valsartan, which was shown to be very low risk of additional cancer incidence. MFDS pronounced strengthening of the safety management for the raw materials of the medicines. For guaranteeing the safety of medicines, more comprehensive drug safety management system from developing new drugs to consuming the medicines should be established. For achieving such a goal, active participation of all the stakeholders of the medicines including governmental agencies including MFDS and Ministry of Health and Welfare, the National Assembly, healthcare professionals, pharmaceutical companies, mass media, and general population including patients should be needed.

Antifibrotic effect of total flavonoids of Astmgali Radix on dimethylnitrosamine-induced liver cirrhosis in rats / 中国结合医学杂志

<p><b>OBJECTIVE</b>To study the effect of total flavonoids of Astmgali Radix (TFA) on liver cirrhosis induced with dimethylnitrosamine (DMN) in rats, and the effect on peroxisome proliferator-activated receptor γ (PPARγ), uncoupling protein 2 (UCP2) and farnesoid X receptor (FXR).</p><p><b>METHODS</b>Fifty-three Sprague-Dawley rats were randomly divided into a control group (10 rats) and a DMN group (43 rats). Rats in the DMN group were given DMN for 4 weeks and divided randomly into a model group (14 rats), a low-dosage TFA group (14 rats) and a high-dosage TFA group (15 rats) in the 3rd week. Rats were given TFA for 4 weeks at the dosage of 15 and 30 mg/kg in the low- and high-TFA groups, respectively. At the end of the experiment blood and liver samples were collected. Serum liver function and liver tissue hydroxyproline content were determined. hematoxylin-eosin (HE), Sirus red and immunohistochemical stainings of collagen I, smooth muscle actin (α-SMA) was conducted in paraffinembedded liver tissue slices. Real time polymerase chain reaction (PCR) was adopted to determine PPARγ, UCP2 and FXR mRNA levels. Western blot was adopted to determine protein levels of collagen I, α-SMA, PPARγ, UCP2 and FXR.</p><p><b>RESULTS</b>Compared with the model group, TFA increased the ratio of liver/body weight (low-TFA group P<0.05, high-TFA group P<0.01), improved liver biochemical indices (P<0.01 for ALT, AST, GGT in both groups, P<0.05 for albumin and TBil in the high-TFA group) and reduced liver tissue hydroxproline content (P<0.01 in both groups) in treatment groups significantly. HE staining showed that TFA alleviated liver pathological changes markedly and Sirus red staining showed that TFA reduced collagen deposition, alleviated formation and extent of liver pseudolobule. Collagen I and α-SMA immunohistochemical staining showed that staining area and extent markedly decreased in TFA groups compared with the model group. TFA could increase PPARγ, it regulated target UCP2, and FXR levels significantly compared with the model group (in the low-TFA group all P<0.05, in the high group all P<0.01).</p><p><b>CONCLUSION</b>TFA could improve liver function, alleviate liver pathological changes, and reduce collagen deposition and formation of liver pseudolobule in rats with liver cirrhosis. The antifibrotic effect of TFA was through regulating PPARγ signal pathway and the interaction with FXR.</p>

Development of Urinary Bladder Pre-Neoplasia by Schistosoma haematobium Eggs and Chemical Carcinogen in Mice

Schistosoma haematobium is a biocarcinogen of human urinary bladder (UB). The present study investigated developing UB cancer mouse model by injecting S. haematobium eggs into the bladder wall and introduction of chemical carcinogens. Histopathological findings showed mild hyperplasia to epithelial vacuolar change, and high grade dysplasia. Squamous metaplasia was observed in the S. haematobium eggs+NDMA group at week 12 but not in other groups. Immunohistochemistry revealed significantly high expression of Ki-67 in urothelial epithelial cells of the S. haematobium eggs+BBN group at week 20. The qRT-PCR showed high expression of p53 gene in S. haematobium eggs group at week 4 and S. haematobium eggs+BBN group at week 20. E-cadherin and vimentin showed contrasting expression in S. haematobium eggs+BBN group. Such inverse expression of E-cadherin and vimentin may indicate epithelial mesenchymal transition in the UB tissue. In conclusion, S. haematobium eggs and nitrosamines may transform UB cells into squamous metaplasia and dysplasia in correlation with increased expression of Ki-67. Marked decrease in E-cadherin and increase in p53 and vimentin expressions may support the transformation. The present study introduces a promising modified animal model for UB cancer study using S. haematobium eggs.

Silibinin alleviates N-nitrosodimethylamine-induced glutathione dysregulation and hepatotoxicity in rats / 中国天然药物

The present study was designed to evaluate the hepatoprotective and antioxidant potentials of silibinin (SBN) against N-nitrosodimethylamine (DMN)-induced toxic insults in the rat liver. The liver damage was induced in Wistar albino rats by repeated administration of DMN (10 mg·kg(-1) b.w., i.p.) on 3 consecutive days per week for 3 weeks. SBN (100 mg·kg(-1) b.w., p.o.) was given daily to the DMN treated rats for two weeks. The marker enzymes of liver toxicity and second-line enzymic and non-enzymic antioxidants were evaluated in serum and liver tissues before and after SBN treatment. Histopathology of the liver was evaluated by H & E staining. The DMN treatment produced a progressive increase in all the serum marker enzymes (AST, ALT, ALP, LDH, and γ-GT), peaking on Day 21. This treatment produced highly significant decreases in all the second-line antioxidant parameters (GSH, GST, GR, GPx, and vitamins C and E). The SBN treatment significantly reversed the DMN-induced damages, towards normalcy. Histopathological studies confirmed the development of liver toxicity in DMN-treated rats, which was reversed by SBN treatment in corroboration with the aforementioned biochemical results, indicating the hepatoprotective and antioxidant properties of SBN. In conclusion, the DMN-induced degenerative changes in the liver were alleviated by SBN treatment and this protective ability may be attributed to its antioxidant, free radical scavenging, and membrane stabilizing properties.

Novel matrine derivative MD-1 attenuates hepatic fibrosis by inhibiting EGFR activation of hepatic stellate cells

Matrine (MT), the effective component of Sophora flavescens Ait, has been shown to have anti-inflammation, immune-suppressive, anti-tumor, and anti-hepatic fibrosis activities. However, the pharmacological effects of MT still need to be strengthened due to its relatively low efficacy and short half-life. In the present study, we report a more effective thio derivative of MT, MD-1, and its inhibitory effects on the activation of hepatic stellate cells (HSCs) in both cell culture and animal models. Cytological experiments showed that MD-1 can inhibit the proliferation of HSC-T6 cells with a half-maximal inhibitory concentration (IC50) of 62 μmol/L. In addition, MD-1 more strongly inhibits the migration of HSC-T6 cells compared to MT and can more effectively induce G0/G1 arrest and apoptosis. Investigating the biological mechanisms underlying anti-hepatic fibrosis in the presence of MD-1, we found that MD-1 can bind the epidermal growth factor receptor (EGFR) on the surface of HSC-T6 cells, which can further inhibit the phosphorylation of EGFR and its downstream protein kinase B (Akt), resulting in decreased expression of cyclin D1 and eventual inhibition of the activation of HSC-T6 cells. Furthermore, in rats with dimethylnitrosamine (DMN)-induced hepatic fibrosis, MD-1 slowed the development and progression of hepatic fibrosis, protecting hepatic parenchymal cells and improving hepatic functions. Therefore, MD-1 is a potential drug for anti-hepatic fibrosis.

C3H/He Mice as an Incompatible Cholangiocarcinoma Model by Clonorchis sinensis, Dicyclanil and N-Nitrosodimethylamine

Clonorchis sinensis is a Group-I bio-carcinogen, associated with cholangiocarcinoma (CCA). The hamster is the only experimental model of C. sinensis-mediated CCA, but we oblige another animal model. The present study intended to develop a C. sinensis (Cs) mediated CCA model using C3H/He mice, co-stimulated with N-nitrosodimethyl-amine (NDMA) and dicyclanil (DC). The mice were divided into 8 groups with different combinations of Cs, NDMA, and DC. Six months later the mice were sacrificed and subjected to gross and histopathological examination. The body weights were significantly reduced among the groups treated with 2 or more agents (eg. Cs+NDMA, Cs+DC, NDMA+DC, and Cs+NDMA+DC). In contrast, liver weight percentages to body weight were increased in above groups by 4.1% to 4.7%. A Change of the spleen weight was observed only in Cs+NDMA group. Though C. sinensis infection is evident from hyperplastic changes, only 1 worm was recovered. T wo mice, 1 from Cs and the other from Cs+DC group, showed mass forming lesions; 1 (281.2 mm3) from the Cs group was a hepatocellular adenoma and the other (280.6 mm3) from the Cs+DC group was a cystic mass (peliosis). Higher prevalence of gray-white nodules was observed in Cs group (42.9%) followed by Cs+NDMA+DC group (21.4%). The mice of the Cs+NDMA+DC group showed hyper-proliferation of the bile duct with fibrotic changes. No characteristic change for CCA was recognized in any of the groups. In conclusion, C3H/He mice produce no CCA but extensive fibrosis when they are challenged by Cs, NDMA, and DC together.

Regulation of α-tocopherol on NFκB and Nrf2 signaling pathway at early stage of N-nitrosomethylbenzylamine⁃induced human esophageal cell carcinogenesis / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the regulation of α-Tocopherol on NFκB and Nrf2 signaling pathway at early stage of N-nitrosomethylbenzylamine (NMBzA)-induced human esophageal carcinogenesis.</p><p><b>METHODS</b>Human normal esophageal HET-1A cells were treated with NMBzA at 50 µmol/L, 100 µmol/L for 24 h to intimate the initiation of esophageal carcinogenesis. For intervention groups, HET-1A cells were pre-treated with α-T at 25, 50, 100 µmol/L for 3 h and then co-treated with NMBzA (100 µmol/L) for 24 h. In comparison with HET-1A cells, human esophageal cancer EC109 cells were treated with α-T at corresponding concentrations. Cells treated with 0.1% DMSO were used as negative control. Immunofluorence staining was used for the determination of distribution and activation of NFκB p65 and Nrf2 in the cell. Real time PCR and Western blot were used to determine the expression levels of target genes including cyclinD1, KI67, proliferating cell nuclear antigen (PCNA), cyclo-oxygen-ase 2 (COX2), 5LOX, HO-1, NQO1 and GCLC. Flow cytometry was utilized to analyze the reactive oxygen species contents in the cells.</p><p><b>RESULTS</b>As compared to the control group (1.00 ± 0.08), the expression of CyclinD1 (2.99 ± 0.15), KI67 (2.35 ± 0.38) and PCNA (2.46 ± 0.25) in HET-1A were all markedly increased by NMBzA treatment (F values were 97.23, 65.28, 34.62, P < 0.001). Also, the proportion of cells with nucleus translocation of NFκB p65 (71.0%, 98/138) or Nrf2 (36.3%, 49/135) were significantly increased (χ² values were 194.71, 133.72, P < 0.001), and the expression of COX2 (3.22 ± 0.17), 5LOX (2.87 ± 0.12) as well as HO-1 (1.87 ± 0.22), NQO1 (2.14 ± 0.08), GCLC (2.63 ± 0.41) at protein levels were elevated (F values were 72.35, 43.87, 69.23, 71.34, 85.79, P values were 0.013, 0.015, 0.010, 0.011, 0.002). Under the treatment with 50 µmol/L α-T, comparing with the control group(59.1%,65/110),the nuclear translocation of NFκB p65 (77.7%, 8/104) was clearly inhibited (χ² = 148.1, P < 0.001), and protein expression levels of COX2 (0.74 ± 0.19) and 5LOX (0.42 ± 0.13) were decreased (F values were 56.31, 73.25, P values were 0.003, 0.001). However, no changes on Nrf2 signaling pathway were observed; α-T showed little impact on NFκB or Nrf2 pathway in EC109 cells.</p><p><b>CONCLUSIONS</b>At the early stage of NMBz-induced esophageal cancer, α-T could block the initiation of carcinogenesis through suppressing the activation of NFκB signaling pathway. It might be the major mechanism by which α-T is potentially chemopreventive to esophageal cancer. During the progression of esophageal cancer, the cells may acquire the adaptive functions to accommodate oxidative stress via activating Nrf2 pathway.</p>

Cost of the Cervical Cancer Screening Program at the Mexican Social Security Institute / Costo del Programa de Detección Oportuna de Cáncer Cervical en el Instituto Mexicano del Seguro Social

Objective. To estimate the annual cost of the National Cervical Cancer Screening Program (CCSP) of the Mexican Institute of Social Security (IMSS). Materials and methods. This cost analysis examined regional coverage rates reported by IMSS. We estimated the number of cytology, colposcopy, biopsy and pathology evaluations, as well as the diagnostic test and treatment costs for cervical intraepithelial neoplasia grade II and III (CIN 2/3) and cervical cancer. Diagnostic test costs were estimated using a micro-costing technique. Sensitivity analyses were performed. Results. The cost to perform 2.7 million cytology tests was nearly 38 million dollars, which represents 26.1% of the total program cost (145.4 million). False negatives account for nearly 43% of the program costs. Conclusion. The low sensitivity of the cytology test generates high rates of false negatives, which results in high institutional costs from the treatment of undetected cervical cancer cases.

Objetivo. Estimar el costo anual del Programa Nacional de Detección Oportuna de Cáncer Cervical en el Instituto Mexicano del Seguro Social (IMSS). Material y métodos. Este análisis de costos examinó las distintas coberturas por región reportadas por el IMSS. Se estimó el número de citologías, colposcopías, biopsias y evaluaciones de patología y los costos de pruebas de diagnóstico y de tratamientos por neoplasia cervical intraepitelial de grado II y III (NIC 2/3) y cáncer cervical. Los costos de las pruebas de diagnóstico se estimaron utilizando una técnica de microcosteo. Se llevó a cabo un análisis de sensibilidad. Resultados. El costo de realizar 2.7 millones de citologías fue de 38 millones de dólares, lo que representa 26.1% del costo total del programa (145.4 millones). Los falsos negativos corresponden a casi 43% de los costos del programa. Conclusiones. La baja sensibilidad de la citología genera un alto número de falsos negativos que resultan en costos elevados para la institución por el tratamiento de estos casos no detectados.

Reverse effect of Yinchenhao decoction in dimethyl nitrosamine-induced hepatic fibrosis in rats / 中国中药杂志

<p><b>OBJECTIVE</b>To discuss the reverse effect of Yinchenhao decoction(YCHD) in dimethyl nitrosamine (DMN)-induced hepatic fibrosis in rats.</p><p><b>METHOD</b>The rat hepatic fibrosis model was established through the intraperitoneal injection with 1% dimethyl nitrosamine (DMN) with a dose of 1.0 mL x kg(-1) x d(-1) for consecutively three weeks, once for the first three days of each. The rats were randomly divided into six groups: the silymarin positive control group (50.0 mg x kg(-1) x d(-1), YCHD high (20.0 g x kg(-1) d(-1)), middle (8.0 g x kg(-1) x d(-1)) and low (3.2 g x kg(-1) x d(-1)) dose groups, the model group and the normal control group. The model group and the normal control group were orally administered with normal saline for consecutively five weeks. The pathologic changes in liver tissues were observed by HE staining. The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), g-glutamyltransferase (g-GGT), hyaluronic acid (HA), laminin (LN), collagen type IV (CIV) and type III procollagen amino terminal peptide (PIIINP) in serum were determined. The metabolite profiling of amino acid and the content of hydroxyproline in liver tissues were also measured.</p><p><b>RESULT</b>Compared with the model group, YCHD high and middle dose groups could significantly reverse the pathologic changes in liver tissues of rats. YCHD could reduce the levels of ALT, AST, gamma-GGT, HA, LN, CIV, PIIINP in serum and the content of hydroxyproline in liver tissues in a dose-dependent manner, and altered the metabolite profiling of amino acid in rat liver tissues.</p><p><b>CONCLUSION</b>YCHD has the effect in reversing dimethyl nitrosamine induced hepatic fibrosis in rats.</p>

Role of ERK1/2 Kinase in the expression of iNOS by NDMA in human neutrophils.

Potential role of ERK1/2 kinase in conjunction with p38 in the regulation of inducible nitric oxide synthase (iNOS) expression and nitric oxide (NO) production, and superoxide anion generation by human neutrophils (PMNs) exposed to N-nitrosodimethylamine (NDMA) was determined. Increased synthesis of NO due to the involvement of iNOS in neutrophils exposed to NDMA was observed. In addition, intensified activation of ERK1/2 and p38 kinases was determined in these cells. Inhibition of kinase regulated by extracellular signals (ERK1/2) pathway, in contrast to p38 pathway, led to an increased production of NO and expression of iNOS in PMNs. Moreover, as a result of inhibition of ERK1/2 pathway, a decreased activation of p38 kinase was observed in neutrophils, while inhibition of p38 kinase did not affect activation of ERK1/2 pathway in these cells. An increased ability to release superoxide anion by the studied PMNs was observed, which decreased after ERK1/2 pathway inhibition. In conclusion, in human neutrophils, ERK1/2 kinase is not directly involved in the regulation of iNOS and NO production induced by NDMA; however, the kinase participates in superoxide anion production in these cells.

Effect of cordyceps polysaccharide on lipid peroxidation of rats with dimethylnitrosamine-induced liver fibrosis / 中国中药杂志

<p><b>OBJECTIVE</b>To observe the pharmacological effect of Cordyceps polysaccharide on dimethylnitrosamine (DMN)-induced liver fibrosis in rats.</p><p><b>METHOD</b>DMN rat liver fibrosis model was established and divided into the normal group (N, n = 6), the model group (M, n = 11), the Cordyceps polysaccharide group (C, n = 8) and the colchicine group (Q, n = 9). During the modeling for four weeks, Cordyceps polysaccharide (60 mg x kg(-1)) and colchicine (0.1 mg x kg(-1)) were orally administered for three weeks, while the model and normal groups were given disinfected water of the same amount.</p><p><b>OBSERVATION</b>serum ALT, AST, GGT and Alb, TBil content; content of hydroxyproline (Hyp) in liver tissues; liver pathology and collagen staining; SOD activity and MDA, GSH, GSH-Px in liver tissues; protein expression of proliferating cell nuclear antigen (PCNA) in liver tissues.</p><p><b>RESULT</b>Serum ALT, AST, GGT, TBil significantly increased, and A1b decreased significantly in the model group. Hepatic Hyp significantly increased in the model group, whereas the index remarkably decreased in the Cordyceps polysaccharide group and the colchicine group. HE staining: the structure of normal hepatic lobules was damaged, with hepatocytes tumefaction and proliferation of connective tissues in portal tracts in the model group, while the Cordyceps polysaccharide group and the colchicine group recorded notable reduction in above pathological changes. Collagen staining: the model group showed hepatic lobule fibrous septum and many intact pseudolobules; while the Cordyceps polysaccharide group and the colchicine group witnessed decrease in collagen deposition. The model group showed significant decrease in SOD, GSH-Px and GSH and increase in MDA, whereas the Cordyceps polysaccharide group and the colchicine group recorded notable growth in GSH and GSH-Px. The model group showed significant decrease in protein expression of PCNA in liver tissues, while the Cordyceps polysaccharide group and the colchicine group showed significant reduction.</p><p><b>CONCLUSION</b>Cordyceps polysaccharide can significantly inhibit DMN-induced liver fibrosis and lipid peroxidation in rats.</p>

Diferenciação de células-tronco em hepatócitos e desenvolvimento de modelo pré-clínico de fibrose hepática para ensaios de terapia celular / Mesenchymal stem cell differentiation in hepatocytes and development of pre-clinic model of hepatic fibrosis for cellular therapy assays

Este trabalho teve como objetivo desenvolver um protocolo para a diferenciação in vitro de células-tronco mesenquimais (CTM) em hepatócitos e a padronização de um modelo animal de fibrose hepática induzida por dimetilnitrosamina (DMN) para ensaios pré-clínicos de transplante de CTM. CTM isoladas de fontes variadas apresentaram morfologia fibroblastóide e aderência ao plástico e o padrão de marcadores de superfície celular esperado na análise por citometria de fluxo. A capacidade de diferenciação osteogênica e adipogênica dessas células foi comprovada pelas colorações de vermelho de alizarina, oil red e azul de toluidina, respectivamente, confirmando, que as células isoladas para este estudo se comportaram como CTM conforme proposto pela Sociedade Internacional de Pesquisa em Células-tronco. A diferenciação hepática foi avaliada quanto à morfologia e capacidade das células diferenciadas de estocar glicogênio confirmada por PAS (ácido periódico-Schiff), de sintetizar albumina confirmada por imunofluorescência, além da capacidade de expressar genes hepato-específicos verificada por ensaios de PCR em tempo real. Com base na literatura para diferenciação hepática, diferentes protocolos de um, dois e três passos foram testados. CTM humanas mostraram capacidade de produzir e estocar glicogênio e de sintetizar albumina, apenas quando diferenciadas com protocolos de três etapas, porém sem uma expressão aumentada dos genes hepato-específicos albumina, α-fetoproteína e c-Met. Uma etapa de diferenciação endodérmica, previamente aplicada à diferenciação hepática, aumentou a capacidade de produzir e estocar glicogênio das CTM diferenciadas. Para a padronização do modelo de fibrose hepática induzida por DMN, foram realizados experimentos de dose-resposta e foi verificado o efeito da hepatectomia em modelos mistos DMN/hepatectomia. A injúria hepática e o efeito do transplante de CTM foram avaliados por análise macroscópica dos fígados, histologia das biópsias de fígados corados com HE e tricromo de Masson e parâmetros bioquímicos séricos. Alterações macroscópicas, histológicas e nos níveis séricos de fosfatase alcalina indicam a indução da fibrose hepática nos ratos Wistar tratados com DMN na dose de 10 µg/g de peso animal por três dias consecutivos durante quatro semanas, mas não observamos nenhum efeito induzido pela hepatectomia. Porém, este modelo com DMN se mostra semelhante a estágios iniciais de uma fibrose hepática. O transplante de 1 x 107 CTM de veia de cordão umbilical humano (VCUH) no modelo de injúria hepática induzida por DMN não resultou em melhora da fibrose, diminuição dos níveis séricos de fosfatase alcalina e nem em ganho de peso dos animais quando comparados aos animais tratados com PBSA após a injúria hepática (grupo placebo). Em conjunto, esses resultados sugerem que CTM humanas se diferenciam após tratamentos mais complexos, onde os indutores hepatogênicos são sequencialmente adicionados ao meio de modo a mimetizar a sinalização durante o desenvolvimento embrionário. O transplante de CTM de VCUH parece não ter efeito positivo em um modelo pré-clínico de injúria hepática similar a estágios iniciais de fibrose. Financiado por CNPq (573578/2008-7) e FAPESP (2007/54260-2)

This study aimed to develop an in vitro differentiation protocol of mesenchymal (MSC) stem cells to hepatocytes and to standardize an animal model for hepatic fibrosis induced by dimethylnitrosamine (DMN) for preclinical transplant assays of MSC. MSC isolated from various sources presented fibroblastoid morphology, plastic adherence, and the expected pattern of cell surface markers by flow cytometry analysis. The capacity of osteogenic, adipogenic and chondrogenic differentiation of these cells was confirmed by alizarin red, oil red and toluidine blue staining, respectively, confirming that the cells isolated for this study behave as MSC, as proposed by the International Society for Stem Cell Research. Hepatogenic differentiation was evaluated by analysis of cell morphology, capacity to store glycogen confirmed by PAS (periodic acid-Schiff), albumin synthesis confirmed by immunofluorescence, as well as hepatic-specific gene expression verified by real time PCR assays. Based on the published literature on hepatic differentiation, several protocols of one, two, and three steps were tested. Human MSC differentiated solely when treated in a three step-protocol, showing the ability to produce and store glycogen and synthesize albumin; however the expression of hepatic-specific genes such as albumin, α-fetoprotein and c-Met was not increased. An endoderm differentiation stage, added to the hepatic differentiation protocol, increased the capacity to produce and store glycogen of differentiated MSC. In order to standardize the model of liver fibrosis induced by DMN, dose-response experiments were performed and the effect of hepatectomy in mixed models DMN/hepatectomy was observed. Severity of liver injury and the effect of cell transplantation were evaluated by macroscopic analysis of the livers, histology of liver biopsies stained with HE and Masson's trichrome, and evaluation of serum biochemical parameters. The macroscopic and histological observations, and altered alkaline phosphatase serum levels indicated the success in inducing liver fibrosis in DMN-treated rats at a dose of 10 µg/g of animal weight for three consecutive days, during four weeks, without any additional effect upon hepatectomy. Transplanting 1 x 107 umbilical cord MSC in the model of liver injury induced by DMN did not result in improvement of the fibrosis, decrease of alkaline phosphatase serum levels, or in weight gain of the treated animals compared to animals treated with PBSA after liver injury (placebo group). Together, these results suggest that human MSC are capable of differentiating to hepatocyte-like cells after more complex protocols, where hepatogenic inducers are sequentially added to the medium in order to mimic signaling that occurs during fetal development. Transplantation of undifferentiated umbilical cord MSC did not have any positive effect in a preclinical liver injury model characterized by an early stage of fibrosis. Supported by CNPq (573578/2008-7) and FAPESP (2007/54260-2)

Effects of Corbrin Shugan capsule on dimethylnitrosamine-induced hepatic fibrosis in rats / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the effects of Corbrin Shugan capsule on dimethylnitrosamine (DMN)-induced hepatic fibrosis in rats.</p><p><b>METHODS</b>Hepatic fibrosis was induced by DMN in AD rats. The serum concentrations of III pro-collagen (III PC),laminin (LN) and tissue inhibitor of metalloproteinase-1(TIMP-1) were determined with ELISA. The concentration of albumin (ALB) in sera and the content of hydroxyproline (Hyp) in liver tissues were determined with chemical colorimetric and HPLC, respectively. The fibrosis area was measured with Motic Med 6.0 digital medical image analysis system.</p><p><b>RESULTS</b>Compared to model group the high-dose (450 mg kg(-1)),mid-dose (270 mg kg(-1)) and low-dose (90 mg kg(-1)) groups of Corbrin Shugan capsule had significantly lower serum content of III PC [34.46 ± 13.95),(36.15 ± 9.46), and (40.58 ± 7.72)ng ml(-1) compared with (49.38 ± 10.95)ng ml(-1),P<0.05 or P<0.01],TIMP-1 [(16.65 ± 4.24),(16.66 ± 4.34),and (18.99 ± 6.05)ng ml(-1) compared with (30.84 ± 14.48)ng ml(-1), P<0.05 or P<0.01], LN [(12.94 ± 4.29), (12.96 ± 3.21),and (15.32 ± 8.00)ng ml(-1) compared with (30.22 ± 17.00)ng ml(-1),P<0.05 or P<0.01] and smaller hepatic fibrosis area [(0.02240 ± 0.01337), (0.02176 ± 0.01460) and (0.02384 ± 0.01405)μm(2) compared with vs (0.03929 ± 0.01732)μm2, P<0.05 or P<0.01]; the high-dose and mid-dose groups of Corbrin Shugan capsule had significantly lower content of Hyp in liver tissues [(0.77 ± 0.09) and (0.81 ± 0.09)μg μmg(-1) compared with (1.06 ± 0.33)μg mg(-1),P<0.05 or P<0.01]; and the high-dose group of Corbrin Shugan capsule significantly increased the content of ALB in sera [(34.02 ± 4.17)g L(-1) compared with (30.25 ± 4.21)g L(-1),P<0.05].</p><p><b>CONCLUSION</b>Corbrin Shugan capsule is effective in treatment of DMN-induced hepatic fibrosis in rats.</p>

Effect of gypenosides on DMN-induced liver fibrosis in rats / 中国中药杂志

<p><b>OBJECTIVE</b>To study the effect of gypenosides on DMN-induced liver fibrosis in rats.</p><p><b>METHOD</b>A rat liver fibrosis model was established by injecting DMN intraperitoneally. Four weeks later, model rats were randomly devided into three groups: the model group, the gypenosides treated group (200 mg x kg(-1)) and the colchicine treated group (0.1 mg x kg(-1)), with 10 specimens for each group. After a 2-week treatment, following parameters were observed: (1) last body weight, weight ratio between liver and spleen; (2) content of liver hydroxyproline (Hyp); (3) activity of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyltransferase (gamma-GT), content of albumin (Alb) and total bilirubin( TBiL) in serum; (4) liver pathology (Sirius red staining and HE staining); (5) activity of liver superoxide dismutase (SOD), glutathione reduced (GSH), glutathione peroxidase (GSH-Px) and content of liver maleic dialdehyde (MDA).</p><p><b>RESULT</b>There were classic liver cirrhosis pathological changes in model groups. Compared with the normal group, liver Hyp content, activity of serum ATL, AST, gamma-GT and content of serum TBiL, MDA of model groups significantly increased; content of serum Alb and liver GSH, activity of liver SOD and GSH-Px decreased significantly in model groups. In comparison with the model group, liver cirrhosis remarkable improved in the gypenosides group, content of liver Hyp reduced significantly (P < 0.01), which was equal to the colchicine group. Compared with the model group, liver function parameters improved markedly in the gypenosides group; liver SOD and GSH-Px activities significantly increased; MDA content reduced significantly (P < 0.05).</p><p><b>CONCLUSION</b>Gypenosides shows an effect in treating DMN-induced liver fibrosis in rats.</p>

Real-time elastography for quantitative assessment of liver fibrosis in a rat model / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the feasibility of real-time elastography for quantitative evaluation of liver fibrosis in a rat model.</p><p><b>METHODS</b>A total of 70 male Wistar rats were included in the group for dimethylnitrosamine (DMN)-induced liver injury, and 10 saline-injected rats were used as normal control. Hepatic injury was induced by a single intraperitoneal injection of DMN at a dose of 50 mg/kg of body weight. Nine or ten rats in the group with DNM injected and one or two rats in the normal control group were randomly selected and sacrificed at each of the following post-injection time: day 5, 7, 10, 14, 21, 24, and 28. And their livers were taken for pathology analysis. All the rats underwent real-time elastography before sacrificed in order to acquire area ratio of low-strain region (% AREA) and liver fibrosis index (LF index) which were compared with the stage of liver fibrosis and grade of necroinflammatory pathologically. By the different data, Spearman correlation analysis, rank-sum test or receiver operating characteristic curve was used.</p><p><b>RESULTS</b>Among 58 successfully modeled rats, there were nine, 13, 14 and 12 rats of S1, S2, S3 and S4 liver fibrosis on pathology, respectively, which were with or without mild necroinflammatory. The other 10 rats were found to be S0 with severe necroinflammatory. Values of LF index and % AREA both increased with liver fibrosis stage (P less than 0.05). There was certain correlation between LF index and liver fibrosis stage (r=0.643, P=0.000), so was % AREA and liver fibrosis stage (r=0.662, P=0.000). As for LF index, Areas under the receiver operating characteristic curve (Az) was 0.943, 0.890, 0.743 and 0.821 for the diagnosis of hepatic fibrosis S1 or higher, S2 or higher, S3 or higher and S4, respectively; as for % AREA, they were 0.948, 0.883, 0.772 and 0.842, respectively. However, we found a significant difference for LF index or % AREA between S0 with and without severe inflammatory activity rats (P=0.005 and P=0.017).</p><p><b>CONCLUSION</b>Real-time elastography is available for quantitative assessment of liver fibrosis in rats induced by DMN, but severe inflammatory activity can affect its accuracy.</p>

Effects of mast cells on degradation of collagen fibers in dimethylnitrosamine-induced hepatic fibrosis of rat / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the relationship between mast cell and hepatic fibrosis by histopathological method and semi-quantitative measurement.</p><p><b>METHODS</b>Seventy-two Wistary male rats, the control group and the normal group of each only 16, experimental group of 40 rat liver fibrosis was induced by injection of DMN and was sampled at eight different time points. HE, histochemistry, immunohistochemistry (ABC method) and immunofluorescence were performed. The size of fibrosis and the number of mast cells were counted. The expression of MMP-2 and TIMP-2 was documented and electron microscopic examination was performed.</p><p><b>RESULTS</b>After injection of DMN, the fibrosis was the most severe in the 2 week (3.72%) and the first month (3.73%, P = 0.2626), and then gradually diminished, although residual fibrosis was still present at 12 months (1.42%, P = 0.0003). The appearance of mast cells began at 2 weeks (1.73 per 200 power field in average by light microscope) after the injection and reached the peak at 4 months (3.06, P = 0.008). Residual amount of mast cells were present at 12 months (1.04, P = 0.045). However, the degree of fibrosis was not proportional or overlapping with the number of mast cells in this experiment model. Mast cells expressed MMP-2 but not TIMP-2.</p><p><b>CONCLUSIONS</b>In the DMN-induced rat liver fibrosis model, mast cell may be an integral player in the pathogenesis of liver fibrosis and may contribute to the degradation of fibrosis by synthesizing and secreting MMP-2.</p>

Uniform designed research on the active ingredients assembling of huangqi decoction for inhibition of DMN-induced liver fibrosis / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To screen out effective ingredients of Huangqi Decoction (HQD) on dimethylnitrosamine (DMN) induced liver fibrosis and its assembling actions.</p><p><b>METHODS</b>(1) DMN solution (0. 5%) was peritoneally injected to rats to prepare the liver fibrosis model for 12 times, starting from the 1st day of modeling to the end of the 4th week. Uniform design method with 4-factor 8-level table was used to optimize the proportion of four ingredients from HQD, including astragaloside (AS), astragalus flavonoids (AF), glycyrrhizae acid (GA), and glycyrrhizae flavonoids (GF). Moreover, the changes of hydroxyproline (Hyp) content in the liver issue and the level of alanine aminotransferase (ALT) in serum were observed as screen indices, and the method of regression analysis was used to find out an optimal combination. (2) A further study for comparing and verifying the efficacy of the obtained optimized prescription was conducted by observing the changes of fibrosis pathology, the content of Hyp in the liver tissue and serum enzyme activity after medication.</p><p><b>RESULTS</b>The optimal proportion of AS and GA was 164:48. Compared with the model group, the content of Hyp in the liver tissue and the levels of ALT, aspartate aminotransferase (AST), and alkaline phosphatase (ALP) in serum decreased significantly, indicating the inhibiting effect of HQD and the AS/GA combination group on hepatic fibrosis formation (P<0.05). The AS/GA combination group was better than AS/GA used alone group in reducing the content of Hyp in the liver tissue and the level of ALT in serum. Furthermore, the AS/GA combination group was better than the HQD group in reducing the level of ALT in serum.</p><p><b>CONCLUSIONS</b>AS and GA were effective ingredients of HQD, and the combination of AS and GA had obvious synergistic effect in reducing liver collagen deposition and decreasing serum ALT activity in DMN-induced liver fibrosis.</p>

Ingestion Exposure to Nitrosamines in Chlorinated Drinking Water

OBJECTIVES: N-Nitrosodimethylamine (NDMA) is classified as a probable human carcinogen by the United States Environmental Protection Agency (US EPA) and is formed during the chlorination of municipal drinking water. In this study, selected nitrosamines were measured in chlorinated drinking water collected from Chuncheon, Kangwon-do, Republic of Korea, and a risk assessment for NDMA was conducted. METHODS: Twelve water samples were collected from 2 treatment plants and 10 household taps. Samples were analyzed for 6 nitrosamines via solid-phase extraction cleanup followed by conversion to dansyl derivatives and high-performance liquid chromatography-fluorescence detection (HPLC-FLD). Considering the dietary patterns of Korean people and the concentration change of NDMA by boiling, a carcinogenic risk assessment from ingestion exposure was conducted following the US EPA guidelines. RESULTS: NDMA concentrations ranged between 26.1 and 112.0 ng/L. NDMA in water was found to be thermally stable, and thus its concentration at the end of boiling was greater than before thermal treatment owing to the decrease in water volume. The estimated excess lifetime carcinogenic risk exceeded the regulatory baseline risk of 10(-5). CONCLUSIONS: This result suggests that more extensive studies need to be conducted on nitrosamine concentration distributions over the country and the source of relatively high nitrosamine concentrations.

Recipe-syndrome correlation and pathogenesis mechanism of Yinchenhao Decoction in intervening dimethylnitrosamine induced liver cirrhosis progress in rats / 中国中西医结合杂志

<p><b>OBJECTIVE</b>Lay on the intervention effect of different classic Chinese medicine recipes for clearing-heat, eliminating dampness and nourishing Gan-Shen, to investigate the recipe-syndrome pathologic foundation of dimethylnitrosamine (DMN) induced liver cirrhosis in rat.</p><p><b>METHODS</b>Liver cirrhosis model rats were made by DMN intra-peritoneally injection for 4 weeks at the dosage of 10 mg/kg body weight, once per day for 3 consecutive days in each week. Excepting the 6 rats for pre-treatment observation, others were divided into 3 groups and gastric infused respectively with saline (model group), Yinchenhao Decoction (YCHD group) and Yiguanjian (YGJ group) in the continuous 2-week modeling period. Besides, a normal group was set up with 10 healthy rats administered by saline. At the end of the 4th week, rats were sacrificed and their blood sample and liver tissue were get for detecting liver function; hepatic histology (HE and Sirus red stain); alpha-smooth muscle actin (alpha-SMA) and hydroxyproline (Hyp) contents, Oxidative stress-related parameters such as malondialdehyde (MDA), glutathione (GSH), and glutathione S-transferase (GST); expressions of alpha-SMA tumor necrosis factor-alpha (TNF-alpha), platelete-derived growth factor (PDGF), liver fatty acid binding protein (L-FABP), and transferrin were determined at the same time.</p><p><b>RESULTS</b>Compared to those in the model group, liver function was improved significantly and content of Hyp, alpha-SMA protein expression decreased remarkably in the YCHD group (P < 0.05), showing significant inhibition on liver cirrhosis formation; while those effect was not shown in the YGJ group. Comparisons of various parameters between groups showed that TNF-alpha, PDGF expression, MDA content and GST activity in liver tissue were decreased and GSH content, L-FABP and transferrin expression were increased significantly at the terminal of the experiment in the YCHD group (P < 0.05), but only increases of TNF-alpha and GSH were shown in the YGJ group (P < 0.05).</p><p><b>CONCLUSION</b>YCHD exerts significant inhibition on DMN-induced cirrhosis formation in rats, and the inflammatory change and peroxidation in liver tissue at liver cirrhosis developing stage of DMN treated rats is the recipe-syndrome pathologic foundation of clearing heat and eliminating-dampness effects of YCHD.</p>

Effect of fuzheng huayu recipe and huangqi tang on DMN-induced experimental liver cirrhosis in rats / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the effects of Fuzheng Huayu recipe and Huangqi tang on DMN-induced experimental liver cirrhosis in rats and explore the therapeutic characteristics of Buxu herbals on liver cirrhosis.</p><p><b>METHOD</b>Liver cirrhosis in rats was induced by intraperitoneally injection of DMN for 4 weeks. Cirrhotic rats were randomly divided into 4 groups: model group, and Fuzheng Huayu recipe group, Huangqi tang group, Fuzheng Huayu recipe combined with Huangqi Tang group. The rats in treatment groups were orally administered with Fuzheng Huayu recipe, Huangqi tang, Fuzheng Huayu recipe combined with Huangqi tang (1:1), respectively. Normal and model control rats were given the equivalent normal saline. The body weight, liver weight and spleen weight were observed when rats were sacrificed. Liver histology was examined by HE staining and Sirius red staining. The liver function parameters including ALT, T. Bil and Alb were determined. The SOD activity and MDA content in liver tissues were also measured. Hepatic hydroxyproline (Hyp) content was determined by Jamall's method. The expression of alpha-SMA was determined by both immunohistochemistry staining and western blot method.</p><p><b>RESULT</b>Compared with normal rats, the serum ALT and T. Bil levels in model rats increased obviously, by contrast, the serum Alb level decreased. There was a significant decline of SOD activity in model rat liver tissue, while the content of MDA and Hyp increased remarkably. A severe deterioration of liver architecture, infiltration of inflammatory cells and deposition of collagen were observed in model rat liver tissue. The expression of alpha-SMA also increased significantly. Compared with model rats, the liver function, lipid peroxidation parameters, Hyp content and liver histology were all improved in the 3 treatment groups. The combined group is better than any single-use group in decreasing collagen deposition and expression of alpha-SMA.</p><p><b>CONCLUSION</b>Fuzheng Huayu recipe, Huangqi tang, Fuzheng Huayu recipe combined with Huangqi tang can attenuate liver fibrosis in DMN induced rats. Fuzheng Huayu recipe combined with Huangqi tang is better than that using alone in decreasing collagen deposition. The mechanism is partially due to the better effect of Fuzheng Huayu recipe combined with Huangqi tang on inhibiting activated HSC.</p>