Anti-FASN monoclonal antibody, clone 4G3-2G4

The metabolic state influences the regulation of neural stem/progenitor cells. The pentose phosphate pathway (PPP), an alternative metabolic pathway that operates parallel to glycolysis, not only provides key intermediates for biosynthetic reactions but also controls the fate of neural stem/progenitor cells. We have previously shown that glutamate application leads to the induction of neural progenitor cells in mature ex vivo rat retina. In this study, we investigated whether regulation of the PPP might be changed following glutamate treatment of the retina. Immunoblot analysis revealed that the amount of glucose-6-phosphate dehydrogenase (G6PD), the rate-limiting enzyme of the PPP as well as that of 6-phosphogluconate dehydrogenase (6PGD), another enzyme in this pathway, increased in the glutamate-treated retina. Consistent with the fact that both these enzymes generate reduced nicotinamide adenine dinucleotide phosphate (NADPH), the amount of NAPDH in the treated retina was significantly higher compared with that in the untreated retina. We also found that both DNA synthesis as well as the expression of fatty acid synthase (FASN) increased significantly in the glutamate-treated retina. Furthermore, hypoxia-inducible factor 1-alpha (HIF-1 alpha), a positive transcriptional regulator of PPP enzymes, was up-regulated at both messenger RNA (mRNA) and protein levels. Finally, we found the interaction of HIF-1 alpha with the M2 isozyme of pyruvate kinase (PKM2), with this interaction having been shown to contribute to a positive feedback loop in the control of glycolysis. Our results thus show that specific metabolic change in the PPP occurs in the process of neural progenitor cell induction in the mature rat retina.

This study evaluated the effect of trans-10, cis-12 CLA on the expression of genes involved in decreasing milk fat synthesis in two groups of lactating ewes with different metabolic weights. Twelve Lacaune ewes were alloted, according to metabolic weight (MW), into a Light Metabolic Weight (LMW) and Heavy Metabolic Weigth (HMW) groups, both of which were orally fed 30 g/d of rumen-unprotected CLA supplement containing 29.9% trans-10, cis-12. Milk samples were collected on days 0, 3 and 10 and mammary and adipose tissue biopsies were taken on days 3 and 10. RNA extraction, cDNA synthesis and RT-qPCR were performed and data were analyzed using the MIXED procedure of SAS as repeated measure in a completely randomized design. The trans-10, cis-12 CLA reduced milk fat synthesis between days 3 and 10 (P = 0.001), and the HMW group had a greater expression (P < 0.05) of the genes acetyl-CoA carboxylase alpha - promoter III (ACACA-alpha PIII), fatty acid synthase (FASN), stearoil CoA desaturase 1 (SCD1) and thyroid hormone responsive spotl4 (THRSP) in the mammary gland and of acetyl-CoA carboxylase alpha - promoter I (ACACA-alpha PI) and leptin (P < 0.05) in adipose tissue. Our findings indicate that the response of animals to trans-10, cis-12 CLA appears to be metabolic weight dependent.