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The therapeutic potential of Baccharis anomala DC. extracts was evaluated through its cytotoxic and antiproliferative effect and their phenotypic reversion property in activated hepatic stellate cells (HSCs). Baccharis anomala is distributed in Brazil (southeastern and south regions) and used for diuretic effect in folk medicine. Four fractions were obtained from the fractionation of the methanolic extract. Fractions III and IV decreased cell proliferation without increasing cell necrosis markers levels and induced cell cycle arrest in G1 phase. Fraction III induced phenotypic reversion through PPAR-γ activation pathway, while fraction IV did not alter PPAR-α/γ expression levels, suggesting that there is an independent PPAR-α/γ pathway involved. Hydroxybenzoic, chlorogenic and coumaric acids were identified. Fractions III and IV showed antiproliferative effect and ability to induce reversion of activated phenotype of HSCs.

Microelectrode implants are an important tool in neuroscience research and in developing brain⁻machine interfaces. Data from rodents have consistently shown that astrocytes are recruited to the area surrounding implants, forming a glial scar that increases electrode impedance and reduces chronic utility. However, studies in non-human primates are scarce, with none to date in marmosets. We used glial fibrillary acidic protein (GFAP) immunostaining to characterize the acute and chronic response of the marmoset brain to microelectrodes. By using densitometry, we showed that marmoset astrocytes surround brain implants and that a glial scar is formed over time, with significant increase in the chronic condition relative to the acute condition animal.

Background: Sepsis is a severe medical condition that ranks among the top 10 causes of death worldwide and which has permanently high incidence rates. Mesenchymal stem cells (MSCs) have been found to be potent modulators of immune responses. More importantly, there is evidence that MSCs have a beneficial effect on preclinical models of polymicrobial sepsis. However, the changes caused by the MSCs in the effector cells of the host immune system remain unclear., Methods: A mouse model of sepsis (male C57BL/6 mice) with three experimental groups was used for experiments in vivo: a control group, an untreated septic group, and a septic group treated with MSCs. In vitro experiments were performed using a cell line of pulmonary macrophages (RAW 264.7) co-cultured with MSCs and stimulated with lipopolysaccharide (LPS)., Results: In vivo we demonstrated that treatment with MSCs was able to reduce the expression of cyclooxygenase-2 (COX-2) and nuclear factor kappa B (NF-κB), and thereby decrease the production of inflammatory cytokines. In vitro experiments using a co-culture of macrophages with MSCs showed a decrease in COX-2 and NF-κB, and showed that this reduction was directly related to the ability of MSCs to inhibit phosphorylation of ERK, RSK, and p38, enzymes that belong to the family of mitogen-activated protein kinases (MAPKs)., Conclusions: This study demonstrated that MSCs are able to inhibit the MAPK pathway activation, modulating the inflammatory response during sepsis. This understanding that MSCs can remodel the response of host cells and improve the course of sepsis is essential for developing new treatments for this pathology.

Hepatic fibrosis is an extracellular matrix deposition by hepatic stellate cells (HSC). Fibrosis can be caused by iron, which will lead to hydroxyl radical production and cell damage. Fructose-1,6-bisphosphate (FBP) has been shown to deliver therapeutic effects in many pathological situations. In this work, we aimed to test the effects of FBP in HSC cell line, GRX, exposed to an excess of iron (Fe). The Fe-treatment increased cell proliferation and FBP reversed this effect, which was not due to increased necrosis, apoptosis or changes in cell cycle. Oil Red-O staining showed that FBP successfully increased lipid content and lead GRX cells to present characteristics of quiescent HSC. Fe-treatment decreased PPAR-γ expression and increased Col-1 expression. Both effects were reversed by FBP which also decreased TGF-β1 levels in comparison to both control and Fe groups. FBP, also, did not present scavenger activity in the DPPH assay. The treatment with FBP resulted in decreased proliferation rate, Col-1 expression and TGF-β1 release by HSC cells. Furthermore, activated PPAR-γ and increased lipid droplets induce cells to become quiescent, which is a key event to reversion of hepatic fibrosis. FBP also chelates iron showing potential to improve Cell redox state.

Hepatic stellate cells (HSC) play a key role in the development of chronic liver disease (CLD). Liraglutide, well-established in type 2 diabetes, showed anti-inflammatory and anti-oxidant properties. We evaluated the effects of liraglutide on HSC phenotype and hepatic microvascular function using diverse pre-clinical models of CLD. Human and rat HSC were in vitro treated with liraglutide, or vehicle, and their phenotype, viability and proliferation were evaluated. In addition, liraglutide or vehicle was administered to rats with CLD. Liver microvascular function, fibrosis, HSC phenotype and sinusoidal endothelial phenotype were determined. Additionally, the effects of liraglutide on HSC phenotype were analysed in human precision-cut liver slices. Liraglutide markedly improved HSC phenotype and diminished cell proliferation. Cirrhotic rats receiving liraglutide exhibited significantly improved liver microvascular function, as evidenced by lower portal pressure, improved intrahepatic vascular resistance, and marked ameliorations in fibrosis, HSC phenotype and endothelial function. The anti-fibrotic effects of liraglutide were confirmed in human liver tissue and, although requiring further investigation, its underlying molecular mechanisms suggested a GLP1-R-independent and NF-κB-Sox9-dependent one. This study demonstrates for the first time that liraglutide improves the liver sinusoidal milieu in pre-clinical models of cirrhosis, encouraging its clinical evaluation in the treatment of chronic liver disease.

Background & Aims: The transcription factor Krüppel-like factor 2 (KLF2), inducible by simvastatin, confers endothelial vasoprotection. Considering recent data suggesting activation of autophagy by statins, we aimed to: 1) characterize the relationship between autophagy and KLF2 in the endothelium, 2) assess this relationship in acute liver injury (cold ischemia/reperfusion) and 3) study the effects of modulating KLF2-autophagy in vitro and in vivo., Methods: Autophagic flux, the vasoprotective KLF2 pathway, cell viability and microvascular function were assessed in endothelial cells and in various pre-clinical models of acute liver injury (cold storage and warm reperfusion)., Results: Positive feedback between autophagy and KLF2 was observed in the endothelium: KLF2 inducers, pharmacological (statins, resveratrol, GGTI-298), biomechanical (shear stress) or genetic (adenovirus containing KLF2), caused endothelial KLF2 overexpression through a Rac1-rab7-autophagy dependent mechanism, both in the specialized liver sinusoidal endothelial cells (LSEC) and in human umbilical vein endothelial cells. In turn, KLF2 induction promoted further activation of autophagy. Cold ischemia blunted autophagic flux. Upon reperfusion, LSEC stored in University of Wisconsin solution did not reactivate autophagy, which resulted in autophagosome accumulation probably due to impairment in autophagosome-lysosome fusion, ultimately leading to increased cell death and microvascular dysfunction. Simvastatin pretreatment maintained autophagy (through the upregulation of rab7), resulting in increased KLF2, improved cell viability, and ameliorated hepatic damage and microvascular function., Conclusions: We herein describe for the first time the complex autophagy-KLF2 relationship, modulating the phenotype and survival of the endothelium. These results help understanding the mechanisms of protection conferred by KLF2-inducers, such as simvastatin, in hepatic vascular disorders., Lay Summary: Autophagy and the transcription factor KLF2 share a common activation pathway in the endothelium, being able to regulate each other. Statins maintain microvascular function through the inhibition of Rac1, which consequently liberates Rab7, activates autophagy and increments the expression of KLF2., (Copyright © 2016 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.)

Hepatocellular carcinoma is the most prevalent primary liver tumor and is among the top ten cancer that affect the world population. Its development is related, in most cases, to the existence of chronic liver injury, such as in cirrhosis. The knowledge about the correlation between chronic inflammation and cancer has driven new researches with anti-inflammatory agents that have potential for the development of antitumor drugs. Gallic acid is a phenolic acid found in many natural products and have shown anti-inflammatory, anti-tumor, anti-mutagenic and antioxidant actions. The purpose of this study was to investigate the effect of gallic acid on acute and chronic cell proliferation and inflammatory parameters of hepatocellular carcinoma cells (HepG2), as well as to investigate the mechanisms involved. Results showed that the gallic acid decreased the proliferation of HepG2 cells in a dose-dependent manner (Trypan blue exclusion assay), without causing necrosis (LDH assay). We observed a significant increase in the percentage of small and regular nuclei (Nuclear Morphometric Analysis assay), a significant induction of apoptosis by Annexin V-FITC and PI assay and no interference with the cell cycle using the FITC BrdU Flow Kit. We observed a significant reduction in the levels of IL-8 and increased levels of IL-10 and IL-12 (Cytometric Bead Array Human Inflammation Assay). Furthermore, gallic acid caused no cancer cells regrowth at a long term (Cumulative Population Doubling assay). According to these results, gallic acid showed a strong potential as an anti-tumor agent in hepatocellular carcinoma cells., (Copyright © 2016 Elsevier Masson SAS. All rights reserved.)

Apoptosis and NETosis of neutrophils are two major mechanisms of programmed cell death that differ in their morphological characteristics and effects on the immune system. Apoptosis can be delayed by the presence of pathogens or chemical components such as lipopolysaccharide (LPS). Neutrophils have other antimicrobial strategy, called neutrophil extracellular traps (NETs), which contributes to the elimination and control of the pathogen. NETosis is induced by infection, inflammation or trauma and represents an innate immune activation mechanism. The objective of this study was to evaluate the effect of gallic acid (GA) in the modulation of apoptosis and NETs release. The results show that GA decreased the anti-apoptotic effect of LPS, blocked the induction of NETs and prevented the formation of free radicals induced by LPS. These findings demonstrate that the GA is a novel therapeutic agent for decreasing the exacerbated response of the body against an infectious agent., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Objective and Design: Mesenchymal stem cells (MSCs) are potent modulators of immune responses. Sepsis is the association of a systemic inflammatory response with an infection. The aim of this study was to test the ability of MSCs derived from adipose tissue, which have immunomodulatory effects, and to inhibit the septic process in an experimental model of mice., Methods: Three experimental groups (male C57BL/6 mice) were formed for the test: control group, untreated septic group and septic group treated with MSCs (1 × 10(6) cells/animal)., Results: In the control group, there were no deaths; in the untreated septic group, the mortality rate was 100 % within 26 h; in the septic group treated with MSCs, the mortality rate reached 40 % within 26 h. The group treated with MSCs was able to reduce the markers of tissue damage in the liver and pancreas. The treated group had a reduction of inflammatory markers. Furthermore, the MSCs-treated group was able to inhibit the increase of apoptosis in splenocytes observed in the untreated septic group., Conclusions: Our data showed that MSCs ameliorated the immune response with decrease of inflammatory cytokines and increase anti-inflammatory IL-10; moreover, inhibited splenocytes apoptosis and, consequently, inhibited tissue damage during sepsis.

(+)-Catechin is a type of catechin present in large amounts in açaí fruits and cocoa seeds. Besides its antioxidant and anti-inflammatory activities, little is known about its effects in the liver, especially during hepatic fibrosis. We report here the effects of (+)-catechin on hepatic stellate cells. (+)-Catechin induced quiescent phenotype in GRX cells, along with an increase in lipid droplets. Proliferator-activated receptor γ mRNA expression was upregulated, whereas type I collagen mRNA expression was downregulated. Pro-inflammatory cytokines were not influenced by (+)-catechin, whereas the levels of interleukin 10 were significantly increased. The data provide evidence that (+)-catechin can reduce hepatic stellate cell activation., (© 2013 International Federation for Cell Biology.)

Hepatic stellate cells (HSC) play a key role in liver fibrogenesis. Activation of PPARγ and inhibition of fibrogenic molecules are potential strategies to block HSC activation and differentiation. Aware that the process of hepatic fibrosis involves inflammatory mediators, various anti-inflammatory substances have been studied in an attempt to revert fibrosis. The purpose of this study was to investigate the in vitro effects of fructose-1,6-bisphosphate (FBP) on HSC phenotype reversion. The results demonstrated that FBP induced quiescent phenotype in GRX cells via PPARγ activation. Significant decrease in type I collagen mRNA expression was observed in the first 24h of treatment. These events preceded the reduction of TGF-β1 and total collagen secretion. Thus, FBP promoted downregulation of HSC activation by its antifibrotic action. These findings demonstrate that FBP may have potential as a novel therapeutic agent for the treatment of liver fibrosis., (© 2013 Elsevier B.V. All rights reserved.)

Hepatic stellate cells (HSC) play a key role in liver fibrogenesis. Activation of PPARγ and inhibition of fibrogenic molecules are potential strategies to block HSC activation and differentiation. A number of natural products have been suggested to have antifibrotic effects for the de-activation and de-differentiation of HSCs. The purpose of this study was to investigate the in vitro effects of capsaicin on HSC de-activation and de-differentiation. The results demonstrated that capsaicin induced quiescent phenotype in GRX via PPARγ activation. Significant decrease in COX-2 and type I collagen mRNA expression was observed in the first 24 h of treatment. These events preceded the reduction of TGF-β1 and total collagen secretion. Thus, capsaicin promoted down-regulation of HSC activation by its antifibrotic and anti-inflammatory actions. These findings demonstrate that capsaicin may have potential as a novel therapeutic agent for the treatment of liver fibrosis.

The aim of this study was to test the hypothesis that the renin-angiotensin system (RAS) components, as well as the oxidative stress system, would respond to early environmental changes. Thus, we have evaluated the effects of neonatal handling on both brain and kidney RAS and oxidative stress. Pups were divided into two groups: nonhandled and handled. The procedure consisted of handling them for 1 min/day in the first 10 days of life. On days 1, 5, and 10, animals were killed by decapitation. Blood samples were collected and the brain and kidneys were removed. Renin, AT(1), and AT(2) mRNA expression were evaluated through RT-PCR. Angiotensin II (ANG II) serum concentration was also measured. An increased ANG II concentration, brain and kidney AT(2) mRNA expression were demonstrated. The kidney mRNA AT(1) expression was decreased. There was also a kidney lipid peroxidation increase and a brain superoxide dismutase and catalase decrease. In conclusion, handling in the neonatal period induces the activation of the angiotensinergic system, as well as modulates its mRNA receptor expression. The oxidative stress balance system seems not to be involved., (Copyright © 2011 Wiley Periodicals, Inc.)