α-Tocopherol prevents lymphoma by improving antioxidant defence system of mice

The altered metabolic pathways of diffuse large B-cell lymphoma not otherwise specified

Altered metabolic fingerprints of Diffuse large B-cell lymphoma, not otherwise specified (DLBCL NOS) may offer novel opportunities to identify new biomarkers and improve the understanding of its pathogenesis. This study aimed to investigate the modified metabolic pathways in extranodal, germinal center B-cell (GCB) and non-GCB DLBCL NOS from the head and neck. Formalin-fixed paraffin-embedded (FFPE) tissues from eleven DLBCL NOS classified according to Hans' algorithm using immunohistochemistry, and five normal lymphoid tissues (LT) were analyzed by high-performance liquid chromatography-mass spectrometry-based untargeted metabolomics. Partial Least Squares Discriminant Analysis showed that GCB and non-GCB DLBCL NOS have a distinct metabolomics profile, being the former more similar to normal lymphoid tissues. Metabolite pathway enrichment analysis indicated the following altered pathways: arachidonic acid, tyrosine, xenobiotics, vitamin E metabolism, and vitamin A. Our findings support that GCB and non-GCB DLBCL NOS has a distinct metabolomic profile, in which GCB possibly shares more metabolic similarities with LT than non-GCB DLBCL NOS.

α-tocopherol ameliorates copper II oxide nanoparticles-induced cytotoxic, biochemical, apoptotic, and genotoxic damages in the rainbow trout gonad cells-2 (RTG-2) culture

We investigated the effects of α-tocopherol on oxidative stress-caused damage caused by copper II oxide nanoparticles (CuO NPs) on Oncorhynchus mykiss gonadal cells (RTG-2) for 24 and 48 h. α-Tocopherol reversed the cell death and alterations in the expressions of genes such as sod1, gpx1a, gpx4b, and igf2 caused by CuO NPs; it also supported the expressions of cat, igf1, and gapdh genes caused by CuO NPs for 24 h and promoted alterations in the expressions of the sod2, gh1, and igf1 genes for 48 h. Additionally, α-tocopherol reversed the caspase 3/7 activity increased by CuO NPs for 24 h and supported it's decrease for 48 h. α-Tocopherol supported the increase in tail DNA (%) affected by CuO NPs for 24 h and reversed it for 48 h. Therefore, α-tocopherol may have the potential to protect against cellular alterations induced by CuO NPs in a time-dependent manner.

Protein Carbonylation and Lipid Peroxidation in Hematological Malignancies

Among the different mechanisms involved in oxidative stress, protein carbonylation and lipid peroxidation are both important modifications associated with the pathogenesis of several diseases, including cancer. Hematopoietic cells are particularly vulnerable to oxidative damage, as the excessive production of reactive oxygen species and associated lipid peroxidation suppress self-renewal and induce DNA damage and genomic instability, which can trigger malignancy. A richer understanding of the clinical effects of oxidative stress might improve the prognosis of these diseases and inform therapeutic strategies. The most common protein carbonylation and lipid peroxidation compounds, including hydroxynonenal, malondialdehyde, and advanced oxidation protein products, have been investigated for their potential effect on hematopoietic cells in several studies. In this review, we focus on the most important protein carbonylation and lipid peroxidation biomarkers in hematological malignancies, their role in disease development, and potential treatment implications.

The Oxygen Paradox, the French Paradox, and age-related diseases

A paradox is a seemingly absurd or impossible concept, proposition, or theory that is often difficult to understand or explain, sometimes apparently self-contradictory, and yet ultimately correct or true. How is it possible, for example, that oxygen "a toxic environmental poison" could be also indispensable for life (Beckman and Ames Physiol Rev 78(2):547-81, 1998; Stadtman and Berlett Chem Res Toxicol 10(5):485-94, 1997)?: the so-called Oxygen Paradox (Davies and Ursini 1995; Davies Biochem Soc Symp 61:1-31, 1995). How can French people apparently disregard the rule that high dietary intakes of cholesterol and saturated fats (e.g., cheese and paté) will result in an early death from cardiovascular diseases (Renaud and de Lorgeril Lancet 339(8808):1523-6, 1992; Catalgol et al. Front Pharmacol 3:141, 2012; Eisenberg et al. Nat Med 22(12):1428-1438, 2016)?: the so-called, French Paradox. Doubtless, the truth is not a duality and epistemological bias probably generates apparently self-contradictory conclusions. Perhaps nowhere in biology are there so many apparently contradictory views, and even experimental results, affecting human physiology and pathology as in the fields of free radicals and oxidative stress, antioxidants, foods and drinks, and dietary recommendations; this is particularly true when issues such as disease-susceptibility or avoidance, "healthspan," "lifespan," and ageing are involved. Consider, for example, the apparently paradoxical observation that treatment with low doses of a substance that is toxic at high concentrations may actually induce transient adaptations that protect against a subsequent exposure to the same (or similar) toxin. This particular paradox is now mechanistically explained as "Adaptive Homeostasis" (Davies Mol Asp Med 49:1-7, 2016; Pomatto et al. 2017a; Lomeli et al. Clin Sci (Lond) 131(21):2573-2599, 2017; Pomatto and Davies 2017); the non-damaging process by which an apparent toxicant can activate biological signal transduction pathways to increase expression of protective genes, by mechanisms that are completely different from those by which the same agent induces toxicity at high concentrations. In this review, we explore the influences and effects of paradoxes such as the Oxygen Paradox and the French Paradox on the etiology, progression, and outcomes of many of the major human age-related diseases, as well as the basic biological phenomenon of ageing itself.

Reduction in Cell Viability and in Homeobox Protein Levels Following in Vitro Exposure to δ-tocopherol in Acute Myeloid Leukemia

δ-Tocopherol (δ-T), the least prevalent tocopherol in our diet, was described to have a more potent anticancer activity in solid tumors compared to the other tocopherols. δ-T induces tumor cell death through peroxisome proliferator-activated receptor γ (PPAR-γ) induction, cyclin-D1 inhibition, and modulation of redox balance. Nevertheless, the role of δ-T in preventing or treating hematologic malignancies has not been studied. In this study, we screened the efficacy of δ-T against six cell lines representing a wide spectrum of hematologic malignancies: Jurkat (acute T-cell leukemia), K-562 (chronic myeloid leukemia), KG-1 [acute myeloid leukemia (AML)], THP-1 (acute monocytic leukemia), TOM-1 (acute lymphoblastic leukemia), and UMCL01-101 (AIDS-associated diffuse large B-cell lymphoma). Interestingly, the AML cell line KG-1 was the only one to be significantly affected at concentrations of δ-T as low as 20 µM. The antileukemic activity of δ-T in AML was verified in a set of primary cells collected from patients newly diagnosed with AML. Apoptotic induction and cell cycle arrest explained the efficacy of δ-T against KG-1 cells. The mechanism of cell growth inhibition of δ-T was through downregulation of cyclin-D1 and a set of homeobox proteins (HOXA9, PBX1, and Cdx2) that have a well-documented role in the pathobiology of AML.

The Two Sides of Vitamin E Supplementation

Vitamin E is a lipid-soluble antioxidant that inhibits lipid peroxidation by scavenging reactive oxygen species, and it is thought to protect against the aging process. Indeed, it is one of the most popular supplements in the US. However, recent studies have revealed that vitamin E has dual effects on the aging process. We discovered that α-tocopherol, the major form of vitamin E in the body, stimulates osteoclast fusion and bone resorption as well as induces an osteoporosis-like phenotype in rodents. Clinical intervention trials have also demonstrated that supplementation with vitamin E is neutral or even harmful for preventing age-related diseases in humans. Therefore, the role of vitamin E as an 'anti-ager' has been called into question. This review outlines the present understanding of the role of vitamin E in age-related disease prevention.

Ellagic acid inhibits PKC signaling by improving antioxidant defense system in murine T cell lymphoma

Antioxidants protect the cells from the damaging effects of reactive oxygen species (ROS). Production of ROS during cellular metabolism is balanced by their removal by antioxidants. Any condition leading to increased levels of ROS results in oxidative stress, which participates in multistage carcinogenesis by causing oxidative DNA damage, mutations in the proto-oncogenes and tumor suppressor genes. Antioxidant defense system is required to overcome the process of carcinogenesis generated by ROS. Antioxidant enzymes are major contributors to endogenous antioxidant defense system. Protein kinase C (PKC) is generally involved in cell proliferation and its over expression leads to abnormal tumor growth. Out of three classes of PKC, classical PKC is mainly involved in cell proliferation and tumor growth. Classical PKC initiates signaling pathway and leads to activation of a number of downstream protein via activation of NF-κB. Therefore any agent which can promotes the endogenous antioxidant defense system should be able to down regulate PKC and NF-κB activation and thus may be useful in reducing cancer progression. To investigate this hypothesis we have tested the effect of antioxidant ellagic acid on antioxidant enzymes and PKC signaling in Dalton's lymphoma bearing (DL) mice. DL mice were treated with three different doses of ellagic acid. The treatment significantly increases the activity and expression of antioxidant enzymes and down regulates the expression of classical isozymes of PKC as well as the activation of NF-κB, indicating that ellagic acid improves antioxidant defense system and PKC signaling via NF-κB which may contribute to its cancer preventive role.