An in vitro model of glucose and lipid metabolism in a multicompartmental bioreactor

2011 ◽  
Vol 7 (1) ◽  
pp. 117-126 ◽  
Author(s):  
Bruna Vinci ◽  
Ellen Murphy ◽  
Elisabetta Iori ◽  
Francesco Meduri ◽  
Silvia Fattori ◽  
...  
2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Kamrul M Hasan ◽  
Meher Parveen ◽  
Alondra Pena ◽  
Amiya P Sinha-Hikim ◽  
Theodore C Friedman

Abstract CARF (Collaborator of ARF), a member of ARF-MDM2-p53 pathway and an emerging multifunctional protein, regulates cellular fate in response to various stresses including oxidative DNA damage and replicative stresses. However, its role in metabolic syndrome (MS) and associated diseases has not been studied. This study, using our well established in vivo and in vitro model systems, examines the role of CARF in the development of non-alcoholic fatty liver disease (NAFLD). Indeed, we have found that, compared to control, CARF expression along with Sirt1, pAMPK and pACC (common biological markers of NAFLD) was significantly decreased in the nicotine and high-fat-diet (HFD) in combination or HFD alone induced fatty livers. Additionally, CARF expression was down regulated in palmitate (PA)-treated HepG2 cells, an in vitro model of steatosis, suggesting that CARF expression is negatively regulated in MS, such as NAFLD. Our study further revealed that shRNA mediated knockdown or lentiviral mediated over expression of CARF induced or reduced endogenous fat accumulation, respectively, in HepG2 cells. We also found that overexpression of CARF lowered the exogenous fat accumulation in PA treated HepG2 cells. RNA seq analysis after CARF knockdown in HEK-293T cells further revealed that genes associated with lipid metabolism and triglyceride (TG) synthesis such as diacylglycerol O-acyltransferase2 (DGAT2), acyl-CoA synthetase long-chain family member 4 and 6 (ACSL4, ACSL6) were upregulated in CARF-depleted cells. Likewise, we also found increased expression of DGAT2 in CARF-depleted HepG2 cells, which enhanced TG synthesis. Intriguingly, consistent with the lipid lowering effects of metformin, an antidiabetic drug, we further found that CARF expression along with pAMPK and Sirt1 were significantly increased in metformin-treated HepG2 cells. However, we also found increased pACC levels in CARF over-expressing cells which was further enhanced in metformin-treated cells, suggesting, for the first time, that CARF may contribute to lipid lowering effect of metformin by inhibiting lipogenesis. We conclude that CARF has a lipid lowering effect in hepatocytes and its down regulation in response to MS perturbs lipid metabolism that may lead to the development of NAFLD.


Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 1156
Author(s):  
Lena Seidemann ◽  
Anne Krüger ◽  
Victoria Kegel-Hübner ◽  
Daniel Seehofer ◽  
Georg Damm

Nonalcoholic fatty liver disease (NAFLD) is among the leading causes of end-stage liver disease. The impaired hepatic lipid metabolism in NAFLD is exhibited by dysregulated PPARα and SREBP-1c signaling pathways, which are central transcription factors associated with lipid degradation and de novo lipogenesis. Despite the growing prevalence of this disease, current pharmacological treatment options are unsatisfactory. Genistein, a soy isoflavone, has beneficial effects on lipid metabolism and may be a candidate for NAFLD treatment. In an in vitro model of hepatic steatosis, primary human hepatocytes (PHHs) were incubated with free fatty acids (FFAs) and different doses of genistein. Lipid accumulation and the cytotoxic effects of FFAs and genistein treatment were evaluated by colorimetric and enzymatic assays. Changes in lipid homeostasis were examined by RT-qPCR and Western blot analyses. PPARα protein expression was induced in steatotic PHHs, accompanied by an increase in CPT1L and ACSL1 mRNA. Genistein treatment increased PPARα protein expression only in control PHHs, while CPTL1 and ACSL1 were unchanged and PPARα mRNA was reduced. In steatotic PHHs, genistein reversed the increase in activated SREBP-1c protein. The model realistically reflected the molecular changes in hepatic steatosis. Genistein suppressed the activation of SREBP-1c in steatotic hepatocytes, but the genistein-mediated effects on PPARα were abolished by high hepatic lipid levels.


Author(s):  
Hoda Keshmiri Neghab ◽  
Mohammad Hasan Soheilifar ◽  
Gholamreza Esmaeeli Djavid

Abstract. Wound healing consists of a series of highly orderly overlapping processes characterized by hemostasis, inflammation, proliferation, and remodeling. Prolongation or interruption in each phase can lead to delayed wound healing or a non-healing chronic wound. Vitamin A is a crucial nutrient that is most beneficial for the health of the skin. The present study was undertaken to determine the effect of vitamin A on regeneration, angiogenesis, and inflammation characteristics in an in vitro model system during wound healing. For this purpose, mouse skin normal fibroblast (L929), human umbilical vein endothelial cell (HUVEC), and monocyte/macrophage-like cell line (RAW 264.7) were considered to evaluate proliferation, angiogenesis, and anti-inflammatory responses, respectively. Vitamin A (0.1–5 μM) increased cellular proliferation of L929 and HUVEC (p < 0.05). Similarly, it stimulated angiogenesis by promoting endothelial cell migration up to approximately 4 fold and interestingly tube formation up to 8.5 fold (p < 0.01). Furthermore, vitamin A treatment was shown to decrease the level of nitric oxide production in a dose-dependent effect (p < 0.05), exhibiting the anti-inflammatory property of vitamin A in accelerating wound healing. These results may reveal the therapeutic potential of vitamin A in diabetic wound healing by stimulating regeneration, angiogenesis, and anti-inflammation responses.


2011 ◽  
Vol 71 (05) ◽  
Author(s):  
M Salama ◽  
K Winkler ◽  
KF Murach ◽  
S Hofer ◽  
L Wildt ◽  
...  

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