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In the present study we investigated the effect of the non-alcoholic fatty liver disease (NAFLD) on the alterations in the activity of neurotransmitters catabolizing enzymes and energy catabolising enzymes, prooxidants, endogenous antioxidants and proinflammatory cytokines in brain tissue of NAFLD rats. Rats were intraperitonealy injected with CCl4 solution at a dose of (0.021 mole/Kg, 20 μL, body weight) three times weekly for four weeks. Acetylcholine esterase (AChE), monoamine oxidase (MAO), prooxidant/ antioxidants status, ATPase, lipid profile and glucose level were estimated spectrophotometrically while inflammatory markers; interleukin 6 and tumor necrosis factor alpha (IL6 and TNF-α) and insulin were assessed by ELISA technique. Our results showed that the induced NAFLD and insulin resistance (IR) were accompanied with hyperglycemia and hyperlipidemia and lowered brain glucose level with elevated ATPase activity, prooxidant status (TBARS level, xanthine oxidase and cytochrome 2E1 activities), and inflammatory markers. Through the induction period AChE activity was significantly increased compared to control in blood, liver and brain tissues. Also, MAO activity was significantly increased in both brain and liver tissue but decreased in serum compared with control. These biochemical data were supported with pathophysiological analysis that showed severe neurodegeneration, pyknosis acuolations and cavitations. These observations warrant the reassessment of the conventional concept that the NAFLD with IR progression may induce disturbances in activities of neurotransmitters catabolising enzymes and energy production accompanied with oxidative stress and metabolic disorders, acting as relative risk factors for brain dysfunction and damage with the development of age-associated neurodegenerative diseases such as Alzheimer's disease.

PPARγ, a ligand-stimulated transcription factor with differentiation promoting activity is overexpressed in a variety of cancers. Perturbation of PPAR-γ signaling is now believed to be a strategy for treatment of several cancers, including breast cancer. A set of genes regulated by PPAR-γ ligands is expected to mediate the antiproliferative and prodifferentiation effects in cancer cells. Because 14-3-3 family of proteins shows a debatable activity and varying expression levels in different tumors, in the studies presented here we explored the transcriptional regulatory role of Pioglitazone on the seven 14-3-3 isoforms presenting in MCF-7 breast cancer cells. This study demonstrated that the potent PPAR-γ agonist, Pioglitazone exerted a regulatory role on expression of 14-3-3 genes where it upregulated 14-3-3 gamma, epsilon, zeta and tau by 3.8, 5.2, 2.7 and 739 folds, respectively. However, it had a negative regulatory effect on 14-3-3 beta, sigma and Eta by 16.94, 4.58 and 2.12 folds, respectively compared with control cells. These results correlated with growth arrest and a great increase in BRCA1 gene expression by 1076 folds. In summary, these findings are the first time showing that PPAR-γ regulates 14-3-3 genes and raises question whether PPAR-γ ligands mediate their anticancer effects via regulation of 14-3-3 proteins. Selected References: 1. Bridges, D. and G.B. Moorhead. 2005. 14-3-3 proteins: a number of functions for a numbered protein. Sci. STKE 2005(296):re10. 2. Chearwae, W. and J. Bright. 2008. PPARγ agonists inhibit growth and expansion of CD133+; brain tumour stem cells. Brit. J. Cancer 99(12): 2044-2053 Citation Format: Ashraf A. Khalil, Nihal F. Kabapy, Fouad N. Sharabi. Genomics of regulatory crosstalk between PPAR gamma & 14-3-3 genes in breast cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4653. doi:10.1158/1538-7445.AM2017-4653