Pyruvate kinase M2 (PKM2) is a glycolytic enzyme expressed in highly proliferating cells. Studies of PKM2 have been focused on its function of promoting cell proliferation in cancer cells. Our laboratory previously discovered that extracellular PKM2 released from cancer cells promoted angiogenesis by activating endothelial cell proliferation and migration. PKM2 activated endothelial cells through integrin αvβ3. Angiogenesis and myofibroblast differentiation are key processes during wound healing. In this dissertation, I demonstrate that extracellular PKM2 released from activated neutrophils promotes angiogenesis and myofibroblast differentiation during wound healing. PKM2 activates dermal fibroblasts through integrin αvβ3 and PI3K signaling pathway. I also claim that extracellular PKM2 plays a role during liver fibrosis. PKM2 protects hepatic stellate cells from apoptosis by activating the survival signaling pathway.

No description available.

Introdução: Fibrose hepática é a resposta cicatricial a lesões celulares agudas ou crônicas do fígado. Produtos derivados do intestino podem chegar ao fígado através da veia porta e mediar resposta inflamatória via receptores TLR4. O aumento de citocinas inflamatórias induz a ativação de células estreladas, fibroblastos periportais e células de Kupffer. A ativação destas células estimula a secreção de TGFβ e a deposição excessiva de colágeno. Assim, a modulação da microbiota intestinal com uso de probióticos poderia reduzir a inflamação e fibrogênese hepática. Objetivo: Avaliar o efeito do Lactobacillus rhamnosus GG (LGG) sobre a fibrose hepática em modelo de hepatopatia colestática crônica em ratos. Métodos: Ratos Wistar (n = 29) adultos machos (299,89g ± 42,89 g) foram submetidos a ligadura de ducto biliar (BDL) ou a manipulação de ducto biliar comum sem ligadura (Ctrl). Após 14 dias, os grupos foram novamente divididos para receber gavagens durante 14 dias: os grupos Ctrl e BDL receberam 1 ml de PBS e os grupos Ctrl-P e BDL-P, 1 ml de PBS contendo 2,5 × 107 UFC de LGG. A eutanásia ocorreu 5 dias após o término do tratamento quando foram coletados amostras de sangue e fígado. Resultados: A ligadura de ducto biliar promoveu redução no peso e na albumina plasmática acompanhado da elevação das provas de disfunção hepatobiliar em comparação aos grupos controle. O tratamento com LGG não alterou os parâmetros séricos ou o peso corporal dos animais. Não houve diferença na atividade de superóxido dismutase (SOD) entre os grupos. A atividade de catalase (CAT) e os níveis de sulfidrilas foram significativamente menores no grupo BDL em relação aos controles. O tratamento com LGG mostrou uma tendência ao aumento dos níveis de sulfidrilas. A razão SOD/CAT foi maior no grupo BDL em relação aos controles e o tratamento com LGG preveniu este desequilíbrio. O tratamento com LGG mostrou uma tendência a redução da razão SOD / CAT. A expressão gênica de Tlr4, Tnfα e Il6 e os níveis de IL1β foram maiores no grupo BDL em relação ao controle. O tratamento com LGG atenuou parcialmente a elevação de IL1β e Tlr4. O grupo BDL-P teve redução da expressão gênica de Il6 em relação ao grupo BDL. A expressão gênica de Tgfβ foi maior no grupo BDL em comparação ao Ctrl. A expressão de metaloproteinases 2 e 9 foi significativamente maior nos grupos BDL e BDLP, sem diferença em relação ao tratamento com LGG. A deposição de colágeno e a reação ductular avaliado pelo conteúdo de citoqueratina 7 (CK7) foi maior nos animais submetidos a ligadura de ducto biliar. O tratamento com LGG reduziu significativamente a deposição de colágeno e conteúdo de CK7 no fígado em comparação com grupo de BDL. Conclusão: O tratamento com LGG foi capaz de reduzir a fibrose hepática, a reação ductular e a expressão gênica de Il6 em modelo de hepatopatia colestática crônica em ratos. / Introduction: Liver fibrosis is a wound-healing response to acute or chronic cellular liver injury. Gut-derived products can reach the liver through the portal vein and mediate inflammatory response via TLR4. The increase of inflammatory cytokines induces the activation of stellate cells, periportal fibroblasts and Kupffer cells. The activation of these cells stimulates the secretion of TGFβ and the excessive collagen deposition. Thus, modulation of gut microbiota using probiotics could reduce inflammation and hepatic fibrogenesis. Aim: To evaluate the effect of Lactobacillus rhamnosus GG (LGG) on liver fibrosis in a model of cholestatic liver disease in rats. Methods: Adult male (n = 29) Wistar rats (299.89 g ± 42.89 g) were subjected to bile duct ligation (BDL) or the manipulation of common bile duct without ligation (Ctrl). After 14 days, groups were again divided to receive gavagens during 14 days: Ctrl and BDL groups received 1 ml of PBS and Ctrl-P and BDL-P groups, 1 ml of PBS containing 2.5 × 107 CFU of LGG. Euthanasia occurred five days after the end of the treatment when were collected samples of blood and liver tissue. Results: The bile duct ligation promoted a reduction in body weight and plasma albumin levels followed by an increase of liver dysfunction parameters in comparison to control groups. LGG treatment did not change serum analyses or body weight of animals. There was no difference in superoxide dismutase activity (SOD) between groups. The catalase activity (CAT) and sulfhydryl levels were significantly lower in the BDL group compared to controls. Treatment with LGG showed a tendency to increase sulfhydryl levels. The SOD / CAT ratio was higher in BDL group compared to controls and treatment with LGG prevented this imbalance. Treatment with LGG showed a tendency to decrease SOD / CAT ratio. The gene expression of Tlr4, Tnfα and Il6 and IL1β levels were higher in the BDL group compared to the control. Treatment with LGG partially attenuated the increase of IL1β and Tlr4. The BDL-P group had decreasing in Il6 gene expression compared to the untreated group. The gene expression of Tgfβ was higher in the BDL group compared to the Ctrl. The expression of metalloproteinases 2 and 9 was significantly higher in BDL and BDL-P groups, with no difference in comparison to treatment with LGG. The collagen deposition and ductular reaction evaluated by the content of cytokeratin 7 (CK7) was higher in animals submitted to the bile duct ligation. The hepatic collagen deposition and CK7 content was significantly decreased in BDL-P compared to BDL group. Conclusion: Treatment with LGG was able to reduce liver fibrosis, ductular reaction and Il-6 gene expression in a model of chronic cholestatic liver disease in rats.

Both SM and ST reduced ALT elevation in rats in the prevention study. In the treatment study, ALT of all rats was resolved. Only ST reduced the fibrosis in both prevention and treatment studies. Maximum reduction of fibrosis compared to control was 44.12% in the prevention group and 56.83% in the treatment group. Activated HSC was decreased and apoptosis increased in rats with improved fibrosis. / Conclusion. ST prevented formation of liver fibrosis and promoted resolution of established fibrosis in the rat model. These effects were mediated through induction of HSC apoptosis in the liver. (Abstract shortened by UMI.) / Hepatic fibrosis results from the wound healing response to prolonged liver insult such as chronic hepatitis. It represents an imbalance of fibrogenesis and fibrolysis, causing formation of scars. Activation and proliferation of hepatic stellate cells (HSC) is a key to fibrogenesis while apoptosis of HSC is associated with resolution of fibrosis. / Intense efforts are currently underway to evaluate potential anti-fibrotic agents in herbal medicine. The study hypothesized that herbs may resolve hepatic fibrosis through induction of apoptosis of HSC. In this study, the anti-fibrotic potentials of fourteen commonly used herbs were examined. The anti-fibrotic effect and the underlying mechanism of two herbs were further investigated in an animal model. / Method. Fourteen herbs including Angelica sinensis(AS), Astragalus membranaceus(AM), Cordyceps sinensis(CS), Curcuma wenyujin(CW), Carthamus tinctorius(CT), Curcuma kwangsinensis(CK), Bupleurum chinensis(BC), Ligusticum chuanxiong(LC), Paeconia lactiflora(PL), Prunus persiea(PP), Poria cocos(PC), Salvia miltorrhiza(SM), Schisandra chinensis(SC) and Stephania tetrandra(ST) were selected for screening based on documented safety and effectiveness, and availability in commercial extracts. These two herbs were also authenticated by chemical profiling using HPLC. / Result. For in vitro bioassay, five herbs, namely Angelica sinensis (AS), Carthamus tinctorius (CT), Ligusticum chuanxiong(LC), Salvia miltiorrhiza(SM) and Stephania tetrandra(ST) demonstrated both anti-proliferative and pro-apoptotic activities in T6. SM and ST showed highest potencies with 51.63% and 44.52% of T6 cells showing apoptotsis respectively. Fas and Bax expression was up-regulated and BclxL expression decreased in HSC after incubation with SM and ST. Fas ligand and Bcl2 expression remained unchanged. / Treatment of chronic liver disease with herbal medicine has been documented in ancient China. Nowadays, practitioners of traditional Chinese medicine (TCM) also use herbs to treat chronic liver disease and it is conceivable that such herbs redress the imbalance between fibrogenesis and fibrolysis. / Chor Sin Yee. / "July 2005." / Adviser: Joseph J. Y. Sung. / Source: Dissertation Abstracts International, Volume: 67-01, Section: B, page: 0172. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 196-217). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

The difference between the number of patients needing transplantation for chronic liver disease and the number of organ donors is growing, drawing attention to the urgent requirement for novel therapies. Chronic liver injury is commonly caused by viral hepatitis, alcohol consumption, obesity and metabolic disorders. Prolonged liver injury leads to fibrosis, hepatic scarring and eventually cirrhosis. This project is based on previous studies demonstrating the therapeutic effects of bone marrow-derived macrophages (BMDM) in a murine model of liver fibrosis. BMDM facilitated fibrosis regression and improved liver regeneration. Pro-resolution macrophages exhibited increased expression of MMPs, growth factors and phagocytosis-related genes. However, macrophages derived from bone marrow are inherently heterogeneous and difficult to genetically manipulate. To overcome this limitation, our laboratory has established a protocol whereby pure populations of macrophages can be produced in significant numbers from murine embryonic stem cells (ESC) in vitro, providing an essentially limitless source of macrophages. The first goal of this project was to compare macrophages derived from ESCs (ESDM) with classical BMDM. ESDM displayed characteristic macrophage morphology, could be activated and responded to different cytokines in vitro, and were functionally phagocytic. However, they displayed some differences in their gene expression profile, and were found to be less phagocytic than BMDM. We then assessed whether ESDM could be used in the treatment of a murine model of hepatic injury induced by carbon tetrachloride administration. ESDM therapy helped in the regression of liver fibrosis, down-regulated the number of fibrogenic myofibroblasts, and activated liver progenitor cells. However, a higher number of ESDM compared to BMDMs were required to exert that effect. To assess whether ESDM may be similar to yolk sac derived tissue-resident macrophages, rather than monocyte-derived, we compared their behaviour in a Kupffer cell repopulation assay. Macrophages were depleted using liposomal clodronate treatment then animals were transplanted with either ESDM or BMDM. We demonstrated that ESDM were more efficient than BMDM at repopulating the Kupffer cell compartment and reversing the effects of liposomal clodronate treatment in mice. It is well known that macrophages are very difficult to genetically modify. So our strategy was to genetically modify ESC and then differentiate them to macrophages that carry the modification. By genetically modifying ESCs, we attempted to produce pro-fibrolytic ESDM that over-express MMP12 which is a member of the matrix metalloproteinase family of genes that mainly degrades elastin, an extracellular matrix component. We initially employed a Tet-On 3G expression system to create an ESC line where MMP12 could be expressed in an inducible manner in differentiated macrophages. However, although this inducible strategy functioned in undifferentiated ESCs we could not induce the expression of MMP12 in differentiated macrophages. In an attempt to overcome possible gene-silencing issues, we designed and constructed an expression strategy such that Mmp12 was expressed specifically in macrophages. The ESC line was built such that Mmp12 expression would be driven by the promoter of macrophage colony stimulating factor-1 receptor gene (Csf-1r or c-fms). Using the CRISPR/Cas9 strategy, we successfully targeted the Mmp12 cDNA to the Csf-1r locus but ESDM that were differentiated from targeted ESC lines did not express Mmp12. Thus, despite having adopted two independent strategies, we have failed to generate genetically modified macrophages. As a first step to translate the therapeutic effects of macrophages into the clinical setting, we optimized a feeder- and serum-free protocol to efficiently generate macrophages from human induced pluripotent stem cells.

Orientador: Márjorie de Assis Golim / Resumo: O vírus da hepatite C (VHC) é responsável por causar hepatite C nas formas aguda ou crônica, sendo a fibrose hepática uma possível consequência da evolução da lesão. Na avaliação da fibrose o método considerado padrão ouro é a biópsia hepática. Com a necessidade de se desenvolver metodologias alternativas à biópsia hepática, escores utilizando biomarcadores séricos têm sido validados, de modo que possam servir para o acompanhamento de indivíduos infectados pelo vírus da hepatite C. Realizou-se estudo retrospectivo, incluindo 94 pacientes portadores crônicos do VHC, genótipo 1, pré-tratamento (naive) ou retratados. Os pacientes foram separados em grupos conforme os resultados da classificação METAVIR dos graus de fibrose (F0 à F4), seja por biópsia hepática ou por elastografia hepática por quantificação de ponto. Além disso, os pacientes foram classificados em grupos de fibrose leve G1 (F1-F2) e fibrose avançada G2 (F3-F4). Metodologias não-invasivas como FIB-4 e APRI foram comparadas ao método denominado FibMaster desenvolvido neste estudo através de análises multivariadas e aprendizado de máquina para elaborar um modelo preditivo de fibrose hepática baseado em variáveis sanguíneas possivelmente associadas ao dano hepático. Os parâmetros estatisticamente mais significantes foram alfa-fetoproteína (AFP), apresentando AUROC de 0.890 para a classificação de fibrose F3-F4 e 0.772 para classificação dos grupos G1-G2, ureia com AUROC de 0.723 para fibrose F2-F3, FIB-4 (AUROC de 0.8... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Hepatitis C virus (HCV) is responsible for causing both acute hepatitis C and chronic form, where the last is commonly associated with liver fibrosis. The evaluation of fibrosis is currently performed mainly through liver biopsy, which is the methodology considered as gold standard in the classification of fibrosis stages. With the necessity of developing new alternative methodologies to hepatic biopsy, scores using serum biomarkers have been validated, thus they can be used to monitor infected individuals with the hepatitis C virus. A retrospective study was carried out including 94 chronic HCV, genotype 1, pre-treatment (naive) or retreated patients. Patients were separated into groups according to the METAVIR classification of degrees of fibrosis (F0 to F4), either by hepatic biopsy or point shear wave-elastography exam. Moreover, patients were classified into groups of mild fibrosis G1 (F1-F2) and advanced fibrosis G2 (F3- F4). Non-invasive methodologies such as FIB-4 and APRI were compared to the method named FibMaster, which was proposed in this study through multivariate analyzes and machine learning, in order to elaborate a predictive model for hepatic fibrosis based on blood biomarkers possibly associated with hepatic injury. The most statistically significant parameters were alpha-fetoprotein (AFP), presenting AUROC of 0.890 for fibrosis classification F3-F4 and 0.772 for the classification of groups G1- G2, urea with an AUROC of 0.723 for fibrosis F2-F3, FIB-4 (AUR... (Complete abstract click electronic access below) / Mestre

<p>Activin B, a TGFβ ligand, is associated with liver inflammatory response. We aimed to investigate whether it modulates liver fibrogenesis. <b> </b>Liver and serum activin B, along with its analog activin A, were analyzed in patients with liver fibrosis from different etiologies and in mouse acute liver injury and liver fibrosis models. Activin B, activin A, or both was immunologically neutralized in progressive or established carbon tetrachloride-induced mouse liver fibrosis. The direct effects of activin B and A on hepatocytes, macrophages, and hepatic stellate cells (HSCs) were evaluated <i>in vitro</i>. In human patients, increased activin B is associated with liver fibrosis irrespective of the etiologies. In mice, activin B exhibited persistent elevation in liver and circulation following the onset of liver injury, whereas activin A displayed transient increases. Neutralizing activin B largely prevented and remarkably regressed liver fibrosis, which was augmented by co-neutralizing activin A in mice. Mechanistically, activin B promoted hepatocyte injury, activated macrophages to release cytokines, and induced a pro-fibrotic expression profile and septa formation in HSCs, which were magnified by activin A. Furthermore, activin B and A interdependently activated the CXCL1/iNOS pathway in macrophages and additively upregulated CTGF transcript in HSCs <i>in vitro</i>. Consistently, the expression of these genes was prohibited by neutralizing either one of these two ligands in injured livers. Activin B potently drives the initiation and progression of liver fibrogenesis. It additively or interdependently cooperates with activin A, directly acts on multiple liver cell populations, and induces liver fibrogenesis.<b> </b>Antagonizing activin B or both activins B and A prevents and regresses liver fibrosis in mouse CCl₄ model, inspiring the development of a novel therapy of chronic liver diseases.</p>

Les stéatopathies métaboliques (NAFLD, non-alcoholic fatty liver diseases) sont des pathologies étroitement associées au diabète de type 2 et à l'obésité. Elles couvrent un spectre de maladies hépatiques s'étendant de la stéatose à la cirrhose. Une des étapes charnières dans l'évolution des NAFLD est l'activation des cellules hépatiques stellaires (CHS) qui sont à l'origine de la fibrogenèse hépatique. Dans ce contexte, nous avons identifié le facteur de transcription PRDM16 comme acteur clé de la fibrogenèse. En effet, nos résultats montrent que PRDM16 est induit dans le foie au cours de la fibrose hépatique chez l'Homme et dans différents modèles murins. Cette augmentation de l'expression de PRDM16 est spécifique aux CHS. Des expériences d'invalidation de Prdm16 dans les CHS démontrent que PRDM16 est nécessaire à l'expression basale et stimulé par TGF-b1 de Col-1a1 et Col-3a1. Cette action de PRDM16 s'explique en partie par sa capacité d'interaction avec SMAD3. Enfin, nous avons également démontré que PRDM16 joue un rôle dans l'activation des CHS car l'invalidation de Prdm16 entraîne la diminution de l'expression d'aSma et l'augmentation de l'expression de Srebp-1c. Cependant les mécanismes par lesquels PRDM16 contrôle l'activation des CHS reste à identifier et feront l'objet des prochaines études. / NAFLD (nonalcoholic fatty liver diseases) are closely linked to type 2 diabetes and obesity and are becoming the first cause in liver chronic diseases around the world. One of the key step in NAFLD progression is the fibrogenesis characterized by hepatic stellate cells (HSC) activation. In this context, we identified PRDM16 as a key factor in this activation. Our first prospective study revealed a correlation between fibrosis score and Prdm16 expression in human biopsies and in murine model of fibrosis. Prdm16 expression is also positively correlated in HSC with the activation state. Our results on Prdm16 invalidation in HSC highlight a role for PRDM16 in the increase expression of Col-11 and Col-31 during HSC activation in part by the binding of PRDM16 to SMAD3. Prdm16 invalidation in HSC also leads to a decrease Sma expression and an increase Srebp-1c expression, showing that PRDM16 control HSC activation through other mechanisms which will be the subject of our next studies.

Introduction: Chronic hepatitis B (CHB) is a viral infection that can lead to development of fibrosis and hepatocellular carcinoma (HCC). Several factors affecting disease progression have been reported, such as sex and region of origin. Liver stiffness and fibrosis can be evaluated using transient elastography. The degree of fibrosis is an important parameter when deciding if treatment and HCC surveillance is indicated. Aim1) To compare patients with CHB according to sex and region of origin regarding the parameters liver stiffness, presence of significant fibrosis, hepatitis B e antigen (HBeAg) positivity, frequency of elevated alanine aminotransferase (ALT) levels and HCC surveillance.2) To identify factors associated with significant liver fibrosis. Methods: 410 patients with a registered doctor’s visit 2015–2018 at the Department of Infectious Diseases at Örebro University Hospital were included. A systematic review of medical records was performed and groups (women-men, regions of origin) were compared. Multivariate logistic regression was used to identify factors associated with significant fibrosis. Results: Men had significantly higher liver stiffness values, higher presence of significant fibrosis, and were more frequently under HCC surveillance compared to women. No other significant differences were found regarding the studied parameters, neither related to sex, nor to region of origin. Factors associated with significant fibrosis were: male sex, elevated ALT levels and hepatitis D virus (HDV) co-infection. Conclusions: Men had a higher frequency of significant fibrosis compared to women. Factors associated with significant fibrosis were male sex, elevated ALT values and HDV co-infection.

Bidens pilosa L. is a traditional Chinese herbal medicine of which was considered as a potential COX2 inhibitor and anti-inflammatory agent. The objective of this study is to discriminate the protective effect of aqueous extract of Bidens pilosa L. leaves (BPLAE) against TAA-induced live fibrosis using an animal model. The herb extracts were administrated via intraperitoneal injection once per week (1.25, 2.5 g/kg), and thioacetamide (200 mg/kg) was injected three times per week and the mice were sacrificed at week 4 and week 8, respectively. Immunohistochemistry staining, Hematoxylin-eosin (HE) staining, Sirius red staining were carried out to evaluate the pathological alterations of mouse livers; in addition, Western blotting was performed to measure the differential expression of £\-smooth muscle actin (£\-SMA) between different treatment groups (vehicle, week 4 and week 8). Hepatic hydroxyproline was also detected in order to compare difference in collagen formation of each group. The results showed that Bidens pilosa L. effectively reduced amount of hepatic hydroxyproline and £\-SMA protein in mice with fibrotic liver induced by TAA. Moreover, in histiopathological exam, the BPLAE treated mice demonstrated a lower collagen and £\-SMA expression, which indicated that BPLAE might reduce degree and severity of liver fibrosis in mice. In conclusion, these results suggested that BPLAE potentially against fibrogenesis in TAA- induced mice liver fibrosis. Additionally, we found that BPLAE might involve in the signaling pathway of MAPK (ERK1/ERK2), which reduced the phosporylation level of p44 but not p42. Further studies using cell base assay to confirm the inhibiting role of BPLAE against cell proliferation or migration is warrant.