Antioxidant and Antitumor Activity of a Bioactive Polyphenolic Fraction Isolated from the Brewing Process

There is increasing interest in identifying natural bioactive compounds that can improve mitochondrial functionality and regulate apoptosis. The brewery industry generates wastewater that could yield a natural extract containing bioactive phenolic compounds. Polyphenols act as antioxidants and have been documented to protect the human body from degenerative diseases such as cardiovascular diseases or cancer. The main aims of our research were to determine the phenolic profile of a crude extract obtained (at pilot scale) from a brewery waste stream and to evaluate the biochemical activity of this extract on the mitochondrial function of a cancer cell line (SH-SY5Y). This work is a basic translational pilot study. The total phenolic content was determined by the Folin-Ciocalteu assay, which revealed that 2.30% of the extract consisted of phenolic compounds. The polyphenols, identified and quantified by reverse-phase-high-performance liquid chromatography and mass spectrometry (RP-HPLC/MS), were mainly flavonoids. After cell culture, the tumoral cells treated with the polyphenolic extract showed enhanced mitochondrial oxidative function, which is likely related to a decrease in oxidative stress and an increase in mitochondrial biogenesis. This type of brewery waste stream, properly treated, may be a promising source of natural antioxidants to replace the synthetic antioxidants currently used in the food industry

Expression of cytosolic NADP(+)-dependent isocitrate dehydrogenase in bovine mammary epithelium: Modulation by regulators of differentiation and metabolic effectors

The cytosolic NADP(+)-dependent isocitrate dehydrogenase (IDH1) catalyzes the conversion of isocitrate to alpha-ketogiutarate in the cytosol, and generates NADPH as a primary source of reducing equivalents for de novo fatty acid synthesis in bovine mammary gland. The enzymatic activity of IDH1 increases dramatically in early lactation in bovine mammary tissue. We hypothesized that the expression of IDHI in bovine is modulated by regulators of mammary epithelial differentiation. To test this hypothesis, we first examined the changes in IDH1 expression in late pregnancy (-20 days) and at various stages (14, 90,120, and 240 days) of lactation in bovine mammary tissue. IDH1 mRNA levels increased by 2.3-fold after parturition compared to late pregnancy and remained elevated thereafter. Next, we examined the effects of extracellular matrix and lactogenic hormones on the expression of IDH1 in cultured BME-UV bovine mammary epithelial cells. We found that expression of IDH1 mRNA increased in parallel with P-casein expression induced by extracellular matrix. Fetal calf serum and insulin repressed, whereas prolactin stimulated the expression of IDH1 mRNA in a dose-dependent fashion. The inhibitory effects of insulin on IDH1 mRNA levels were antagonized by cotreatment wit prolactin. In contrast, treatment with prolactin in the presence of extracellular matrix further increased IDH1 mRNA and protein accumulation. Prolactin-induced IDH1 expression was inhibited by the mitogen-activated protein kinase (MAPK) inhibitors PD98059 and U0126, and Janus tyrosine kinase 2 (Jak2) inhibitor AG490, suggesting that both MAPK and Jak2 contribute to regulation of IDH1 expression by prolactin. Finally, we report that treatment of BME-UV cells with a-ketoglutarate and palmitic acid reduced IDH1 transcript levels. Taken together, our data suggest that the expression of IDH1 in bovine mammary epithelium is modulated by regulators of differentiation including extracellular matrix and lactogenic hormones as well as metabolic effectors