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Introduction and objective. Non-alcoholic fatty liver disease remains as one of the main liver disorders worldwide. It is widely accepted that is the kind of lipid, rather than the amount deposited in the cells that determines cell damage. Cholesterol and saturated free fatty acids are deleterious lipids when accumulated but, in contrast, there are some valuable lipids that could counteract those with harmful properties. Much of this knowledge arises from studies using a single fatty acid, but the effects of a combination of fatty acids, as obtained by diet has been poorly addressed. In the present work, we were focused to figure out the cellular effect of two different mixes of fatty acids, one with high proportion of saturated fatty acids, and another one with high proportion of unsaturated fatty acids (Mediterranean-like) in a cellular model of steatosis. Material and methods. Primary mouse hepatocytes from animals fed with a western diet (high fat and carbohydrates diet), were treated with both mixes of fatty acids for 24 h. Results. Our data clearly show that only the high unsaturated fatty acid mix induced a decrease in triglycerides (47.5%) and cholesterol (59%) content in steatotic hepatocytes mediating cellular protection associated to the decrement of ROS and oxidative damage. The mixture of high saturated fatty acids exhibited no effects, preserving high levels of cholesterol and triglycerides and oxidative damage. In conclusion, our results show that Mediterranean-like mix of fatty acids exerts cellular protection in steatosis by decreasing triglycerides, cholesterol, ROS content and oxidative damage.

Introduction and Objectives: Hepatocellular carcinoma (HCC) is the most common and aggressive form of liver cancer. Until 2020, worldwide, it has been ranked 5th and 3rd in terms of incidence and mortality, respectively. HCC has various etiologies, but tumors formed by high cholesterol intake induce an aggressive phenotype and high tumor-associated macrophages (TAM) infiltration. TAM acquires an alternative polarity (M2) with immunosuppressive and pro-tumoral activities. HCC patients with high TAM recruitment have a poor prognosis with a low free-survival rate. The design of therapies represents a challenge. The growth differentiation factor 11 (GDF11) has been proposed as a promising molecule for treating HCC, favors a reduction in proliferation, invasion, and lipid metabolism, and therefore reduces the aggressive phenotype. In our research group, we have found that GDF11 also has various effects on cells belonging to the tumor microenvironment, particularly in TAM. Aim: To evaluate TAM polarity and their intercommunication with HCC-derived cells during treatment with GDF11. Materials and Methods: THP-1-macrophages cell line was used; lipopolysaccharides were used for the M1 polarity acquisition and IL-4/13 or conditioned medium (CM) derived from Huh-7 cells for M2 polarity acquisition, flow cytometry (FCM) was used. GDF11 (50 ng/mL) was applied every 24 h up to 3 days. We used anti-Smad2 and 3 antibodies in Western blot (WB). Cell viability and proliferation studies were performed using crystal violet. The quantification of cholesterol was performed using o-Phthaldialdehyde and free radicals’ detection was performed using dihydroethidium. Data were presented as mean ± standard error of the mean (SEM). The analysis of variance (ANOVA) test was used to compare the mean values ​​between groups. Each result has at least 3 independent experiments. Statistical significance was indicated with an asterisk (*P

Introduction and Objectives: HCC is one of the main causes of cancer-related death worldwide and has third place in mortality. One of the main risk factors is metabolic-associated fatty liver disease (MAFLD), having hepatic steatosis, and related metabolic disorders. Mexican population has the highest obesity rate in both children and adults, and the consumption of hypercaloric diets has been related to that. Also, Mexico is in the top five countries with a higher fructose-enriched diet consumption and has been proved already the relation between fructose consumption and MAFLD. Likewise, fructose has been related to metabolic rewiring in transformed cells, enhancing aggressiveness and survival. Aim: To analyze fructose role on aggressiveness promotion of HCC cells. Materials and Methods: We used C57Bl/6J mice strain (both sex) with a high Fructose diet (Fru) (33% of fructose in the drinking water, ad libitum). Fru supplementation started with 15 days-old mice, two days after DEN was injected (10 μg/Kg, i.p), and the treatment was ended 8 months later. The UAM ethics committee approved the protocol. In vitro studies were carried out with the Huh-7 HCC cell line and we evaluated metabolic and biochemical parameters. Results: Tissue samples were analyzed by H&E. We observed that the fructose-enriched diet group mice presented fat accumulation in the hepatocytes and also areas with a greater inflammatory infiltrate (Fru). Mice in the fructose-enriched diet + DEN (Fru/HCC) group showed a marked difference between the tumor area and the surrounding tissue and an increase in the number of bile ducts, indicating liver tissue damage. Also, we analyzed the protein content of some lipogenic enzymes and noticed an increment in fatty acid synthase (Fasn) in Fru and Fru/HCC. Due to that, we analyzed if Fru treatment was inducing metabolic rewiring in transformed cells. We obtained metabolic changes in fructose-treated cells, reducing the glycolytic pathway and the traditional Warburg effect. Then we evaluated if the Huh-7 under a Fru treatment was more dependent on mitochondria or glycolysis ATP generation. We observed a reduction in proliferation under oligomycin treatment vs. 2-DG treatment. At least, we evaluated the pentose phosphate pathway (PPP) under a Fru treatment and obtained a higher glucose-6-phosphate dehydrogenase (G-6-P DH) activity with Fru vs. only glucose (Glc). Also, G-6-P DH had a more efficient activity in the presence of Fru because the time to reach the Vmax is lower vs. Glc. Conclusion: Fructose induces a metabolic rewiring in cancer cells to enhance ATP production, NADPH, and nucleotides to sustain the active lipid synthesis and proliferation. The fructose-enriched diets promote an aberrant lipogenic phenotype enhancing tumor aggressiveness. Conacyt, Froteras de la Ciencia 1320.The authors declare that there is no conflict of interest.

Introduction and objectives: It is well-known that signaling mediated by the hepatocyte growth factor (HGF) and its receptor c-Met in the liver is involved in the control of cellular redox status and oxidative stress, particularly through its ability to induce hepatoprotective gene expression by activating survival pathways in hepatocytes. It has been reported that HGF can regulate the expression of some members of the NADPH oxidase family in liver cells, particularly the catalytic subunits and p22phox. In the present work we were focused to characterize the mechanism of regulation of p22phox by HGF and its receptor c-Met in primary mouse hepatocytes as a key determinant for cellular redox regulation. Materials and methods: Primary mouse hepatocytes were treated with HGF (50 ng/mL) at different times. cyba expression (gene encoding p22phox) or protein content were addressed by real time RT-PCR, Western blot or immunofluorescence. Protein interactions were explored by immunoprecipitation and FRET analysis. Results: Our results provided mechanistic information supporting the transcriptional repression of cyba induced by HGF in a mechanism dependent of NF-κB activity. We identified a post-translational regulation mechanism directed by p22phox degradation by proteasome 26S, and a second mechanism mediated by p22phox sequestration by c-Met in plasma membrane. Conclusion: Our data clearly show that HGF/c-Met exerts regulation of the NADPH oxidase by a wide-range of molecular mechanisms. NADPH oxidase-derived reactive oxygen species regulated by HGF/c-Met represents one of the main mechanisms of signal transduction elicited by this growth factor.