scholarly journals Energy determinants GAPDH and NDPK act as genetic modifiers for hepatocyte inclusion formation

2011 ◽  
Vol 195 (2) ◽  
pp. 217-229 ◽  
Author(s):  
Natasha T. Snider ◽  
Sujith V.W. Weerasinghe ◽  
Amika Singla ◽  
Jessica M. Leonard ◽  
Shinichiro Hanada ◽  
...  

Genetic factors impact liver injury susceptibility and disease progression. Prominent histological features of some chronic human liver diseases are hepatocyte ballooning and Mallory-Denk bodies. In mice, these features are induced by 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) in a strain-dependent manner, with the C57BL and C3H strains showing high and low susceptibility, respectively. To identify modifiers of DDC-induced liver injury, we compared C57BL and C3H mice using proteomic, biochemical, and cell biological tools. DDC elevated reactive oxygen species (ROS) and oxidative stress enzymes preferentially in C57BL livers and isolated hepatocytes. C57BL livers and hepatocytes also manifested significant down-regulation, aggregation, and nuclear translocation of glyceraldehyde 3-phosphate dehydrogenase (GAPDH). GAPDH knockdown depleted bioenergetic and antioxidant enzymes and elevated hepatocyte ROS, whereas GAPDH overexpression decreased hepatocyte ROS. On the other hand, C3H livers had higher expression and activity of the energy-generating nucleoside-diphosphate kinase (NDPK), and knockdown of hepatocyte NDPK augmented DDC-induced ROS formation. Consistent with these findings, cirrhotic, but not normal, human livers contained GAPDH aggregates and NDPK complexes. We propose that GAPDH and NDPK are genetic modifiers of murine DDC-induced liver injury and potentially human liver disease.

1993 ◽  
Vol 21 (4) ◽  
pp. 466-469
Author(s):  
Peter Olinga ◽  
Marjolijn T. Merema ◽  
Dick K.F. Meijer ◽  
Maarten J.H. Slooff ◽  
Geny M.M. Groothuis

In order to investigate whether liver slices are a valuable tool for the assessment of drug metabolism in human liver, we compared the phase I metabolism of lidocaine in human liver slices and hepatocytes prepared from three human livers. Lidocaine is mainly metabolised to monoethylglycinexykdide (MEGX) via a cytochrome P450-mediated N-deethylation. The results indicate that the three livers showed considerable inter-individual differences in the rate of formation of MEGX, and that this difference was equally reflected in slices and isolated cells. The use of liver slices is still under development, and optimal incubation conditions still need to be assessed. However, these results suggest that, in slices of 200–300μm thickness, virtually all hepatocytes are involved in the biotransformation of lidocaine, and that the metabolic activity is preserved equally well as in isolated hepatocytes.


2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Baoyi Liu ◽  
Yongyi Xie ◽  
Zhouwei Wu

Astragalus membranaceus root has been widely used for repigmentation treatment in vitiligo, but its mechanism is poorly understood. We sought to investigate the effect of astragaloside IV (AS-IV), a main active extract of the Astragalus membranaceus root, on melanin synthesis in normal human epidermal melanocytes (NHEMs) and to elucidate its underlying mechanisms. Melanin content, tyrosinase activity, qPCR, western blot, and immunofluorescence were employed. Specific inhibitors and small interfering RNA were used to investigate the possible pathway. AS-IV stimulated melanin synthesis and upregulated the expression of melanogenesis-related genes in a concentration-dependent manner in NHEMs. AS-IV could activate the aryl hydrocarbon receptor (AhR), and AS-IV-induced melanogenesis was inhibited in si-AhR-transfected NHEMs. In addition, we showed that AS-IV enhanced the phosphorylation of AKT and GSK-3β and nuclear translocation of β-catenin. AS-IV-induced MITF expression upregulation and melanin synthesis were decreased in the presence of β-catenin inhibitor FH353. Furthermore, AhR antagonist CH223191 inhibited the activation of AKT/GSK-3β/β-catenin signaling, whereas the expression of CYP1A1 (marker of AhR activation) was not affected by the AKT inhibitor in AS-IV-exposed NHEMs. Our findings show that AS-IV induces melanogenesis through AhR-dependent AKT/GSK-3β/β-catenin pathway activation and could be beneficial in the therapy for depigmented skin disorders.


2020 ◽  
Author(s):  
Janna C. Nawroth ◽  
Debora B. Petropolis ◽  
Dimitris V. Manatakis ◽  
Tengku Ibrahim Maulana ◽  
Gabriel Burchett ◽  
...  

AbstractFatty liver disease (FLD), is a major public health burden that affects up to 30% of people in Western countries and leads to progressive liver injury, comorbidities, and increased mortality. Key risk factors for developing FLD are obesity and alcohol consumption, both of which are growing in prevalence worldwide. There is an urgent need for human-relevant preclinical models to improve our understanding of FLD progression to steatohepatitis and for the development of sensitive noninvasive diagnostics and therapies. Alcohol-induced liver disease (ALD) represents an ideal case for modeling FDL as ethanol exposure is a comparatively simpler trigger for experimental induction of the pathology, as opposed to the complexity of modeling the diet- and life-style induced FLD. Further, despite their different root causes, the two pathologies share several common characteristics in disease progression and deterioration of liver function, highlighting the potential of an ALD microphysiological model for broad application in translational research. Here, we leverage our recently reported human Liver-Chip for toxicity applications, to expand the capabilities of the platform for broad application in translational research. We report the first in vitro modeling of ALD that uses human relevant blood alcohol concentrations (BAC) and affords multimodal profiling of clinically relevant endpoints. Our ALD Liver-Chip recapitulates established FLD markers in response to ethanol in a concentration-dependent manner, including lipid accumulation and oxidative stress. Importantly, we show that the ALD Liver-Chip supports the study of secondary insults common in patients with advanced ALD, such as high blood endotoxin levels due to alcohol-associated increased intestinal permeability and barrier dysfunction. Moreover, owing to new developments in the design, the ALD Liver-Chip enables the measurement of structural changes of the bile canaliculi (BC) network as a novel in vitro quantitative readout of alcoholic liver toxicity. In summary, we report the development of a human ALD Liver-Chip as a new platform for modeling the progression of alcohol-induced liver injury with direct translation to clinical research.


2006 ◽  
Vol 44 (01) ◽  
Author(s):  
T Mansuroglu ◽  
J Dudas ◽  
B Saile ◽  
D Batusic ◽  
G Ramadori

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Ke-Wu Zeng ◽  
Jing-Kang Wang ◽  
Li-Chao Wang ◽  
Qiang Guo ◽  
Ting-Ting Liu ◽  
...  

AbstractMitochondrial fusion/fission dynamics plays a fundamental role in neuroprotection; however, there is still a severe lack of therapeutic targets for this biological process. Here, we found that the naturally derived small molecule echinacoside (ECH) significantly promotes mitochondrial fusion progression. ECH selectively binds to the previously uncharacterized casein kinase 2 (CK2) α′ subunit (CK2α′) as a direct cellular target, and genetic knockdown of CK2α′ abolishes ECH-mediated mitochondrial fusion. Mechanistically, ECH allosterically regulates CK2α′ conformation to recruit basic transcription factor 3 (BTF3) to form a binary protein complex. Then, the CK2α′/BTF3 complex facilitates β-catenin nuclear translocation to activate TCF/LEF transcription factors and stimulate transcription of the mitochondrial fusion gene Mfn2. Strikingly, in a mouse middle cerebral artery occlusion (MCAO) model, ECH administration was found to significantly improve cerebral injuries and behavioral deficits by enhancing Mfn2 expression in wild-type but not CK2α′+/− mice. Taken together, our findings reveal, for the first time, that CK2 is essential for promoting mitochondrial fusion in a Wnt/β-catenin-dependent manner and suggest that pharmacologically targeting CK2 is a promising therapeutic strategy for ischemic stroke.


2020 ◽  
Vol 63 (1) ◽  
Author(s):  
Jia Jia ◽  
Xigang Kang ◽  
Yanfang Liu ◽  
Jianwei Zhang

Abstract Evodiamine is an active alkaloid member found in Traditional Chinese Herb (TCH) Evodia rutaecarpa. It has been reported to exhibit remarkable biological and medicinal activities including anticancer and anti-inflammatory. This study was designed to investigate the anticancer effects of evodiamine against human liver cancer and evaluate its effects on cell migration, cell invasion, cellular apoptosis and PI3K/AKT pathway. The results showed that evodiamine exhibits potent antiproliferative effects against two human liver cancer cell lines (HepG2 and PLHC-1) with an IC50 of 20 µM. Nonetheless, the cytotoxic effects of evodiamine were comparatively low against the normal cells as evident from the IC50 of 100 μM. The growth inhibitory effects of evodiamine were found to be due to the induction of apoptosis as revealed by the DAPI, AO/EB and annexin V/PI staining assays. The induction of apoptosis was also associated with upregulation of Bax and downregulation of Bcl-2 expression in a concentration dependent manner. The wound healing and transwell assay revealed that evodiamine caused a significant decline in the migration and invasion of the HepG2 and PLHC-1 cells. Investigation of the effects of evodiamine on the PI3K/AKT signalling revealed that evodiamine inhibited the phosphorylation of PI3K and AKT proteins. Taken together, the results showed that evodiamine inhibits the growth of human liver cancer via induction of apoptosis and deactivation of PI3K/AKT pathway. The results point towards the therapeutic potential of evodiamine in the treatment of liver cancer.


Biomedicines ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 420
Author(s):  
Su-Jung Hwang ◽  
Ye-Seul Song ◽  
Hyo-Jong Lee

Kushen (Radix Sophorae flavescentis) is used to treat ulcerative colitis, tumors, and pruritus. Recently, phaseolin, formononetin, matrine, luteolin, and quercetin, through a network pharmacology approach, were tentatively identified as five bioactive constituents responsible for the anti-inflammatory effects of S. flavescentis. However, the role of phaseolin (one of the primary components of S. flavescentis) in the direct regulation of inflammation and inflammatory processes is not well known. In this study, the beneficial role of phaseolin against inflammation was explored in lipopolysaccharide (LPS)-induced inflammation models of RAW 264.7 macrophages and zebrafish larvae. Phaseolin inhibited LPS-mediated production of nitric oxide (NO) and the expression of inducible nitric oxide synthase (iNOS), without affecting cell viability. In addition, phaseolin suppressed pro-inflammatory mediators such as cyclooxygenase 2 (COX-2), interleukin-1β (IL-1β), tumor necrosis factor α (TNF-α), monocyte chemoattractant protein-1 (MCP-1), and interleukin-6 (IL-6) in a dose-dependent manner. Furthermore, phaseolin reduced matrix metalloproteinase (MMP) activity as well as macrophage adhesion in vitro and the recruitment of leukocytes in vivo by downregulating Ninjurin 1 (Ninj1), an adhesion molecule. Finally, phaseolin inhibited the nuclear translocation of nuclear factor-kappa B (NF-κB). In view of the above, our results suggest that phaseolin could be a potential therapeutic candidate for the management of inflammation.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Lama Tarayrah-Ibraheim ◽  
Elital Chass Maurice ◽  
Guy Hadary ◽  
Sharon Ben-Hur ◽  
Alina Kolpakova ◽  
...  

AbstractDuring Drosophila embryonic development, cell death eliminates 30% of the primordial germ cells (PGCs). Inhibiting apoptosis does not prevent PGC death, suggesting a divergence from the conventional apoptotic program. Here, we demonstrate that PGCs normally activate an intrinsic alternative cell death (ACD) pathway mediated by DNase II release from lysosomes, leading to nuclear translocation and subsequent DNA double-strand breaks (DSBs). DSBs activate the DNA damage-sensing enzyme, Poly(ADP-ribose) (PAR) polymerase-1 (PARP-1) and the ATR/Chk1 branch of the DNA damage response. PARP-1 and DNase II engage in a positive feedback amplification loop mediated by the release of PAR polymers from the nucleus and the nuclear accumulation of DNase II in an AIF- and CypA-dependent manner, ultimately resulting in PGC death. Given the anatomical and molecular similarities with an ACD pathway called parthanatos, these findings reveal a parthanatos-like cell death pathway active during Drosophila development.


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