Vitamin E regulatory mechanisms.
ABSTRACT Dietary and supplemental vitamin E is absorbed and delivered to the liver, but of the various antioxidants with vitamin E activity, only alpha-tocopherol is preferentially recognized by the alpha-tocopherol transfer protein (alpha-TTP) and is transferred to plasma, while the other vitamin E forms (e.g., gamma-tocopherol or tocotrienols) are removed from the circulation. Hepatic alpha-TTP is required to maintain plasma and tissue alpha-tocopherol concentrations. The liver is the master regulator of the body's vitamin E levels in that it not only controls alpha-tocopherol concentrations, but also appears to be the major site of vitamin E metabolism and excretion. Vitamin Es are metabolized similarly to xenobiotics; they are initially omega-oxidized by cytochrome P450s, undergo several rounds of beta-oxidation, and then are conjugated and excreted. As a result of these various mechanisms, liver alpha-tocopherol and other vitamin E concentrations are closely regulated; thus, any potential adverse vitamin E effects are limited.
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ABSTRACT: Biochemical markers (Total protein, Vitamin C, Vitamin E, Acetylcholinesterase, and Metallothioneins) induced by acute exposure of Zn&pb in Snail (Viviparus bengalensis) to show their response against these metals. These makers in snail sp. showed different significance response according to Zn acute exposure. So increased and decreased as reaction against acute exposure, The same trend adapted from biomarkers after pb acute exposure in snail sp. while the different response was appeared from these biomarkers after interaction acute exposure.Mesopotamia Environmental Journal (MEJ). 11/2014; 1(1):47-55.
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ABSTRACT: Introduction: Parenteral nutrition (PN) in preterm infants leads to PN-associated liver disease (PNALD). PNALD has been linked to serum accumulation of phytosterols that are abundant in plant oil but absent in fish oil emulsions. Hypothesis: Whether modifying the phytosterol and vitamin E composition of soy and fish oil lipid emulsions affects development of PNALD in preterm pigs. Methods: We measured markers of PNALD in preterm pigs that received 14 days of PN that included 1 of the following: (1) Intralipid (IL, 100% soybean oil), (2) Intralipid + vitamin E (ILE, d-α-tocopherol), (3) Omegaven (OV, 100% fish oil), or (4) Omegaven + phytosterols (PS, β-sitosterol, campesterol, and stigmasterol). Results: Serum levels of direct bilirubin, gamma glutamyl transferase, serum triglyceride, low-density lipoprotein, and hepatic triglyceride content were significantly lower (P < .05) in the ILE, OV, and PS compared to IL. Hepatic cholesterol 7-hydroxylase and organic solute transporter-α expression was lower (P < .05) and portal plasma FGF19 higher in the ILE, OV, and PS vs IL. Hepatic expression of mitochondrial carnitine palmitoyltransferase 1A and microsomal cytochrome P450 2E1 fatty acid oxidation genes was higher in ILE, OV, and PS vs IL. In vivo (13)C-CDCA clearance and expression of pregnane X receptor target genes, cytochrome P450 3A29 and multidrug resistance-associated protein 2, were higher in ILE, OV, and PS vs IL. Conclusions: α-tocopherol in Omegaven and added to Intralipid prevented serum and liver increases in biliary and lipidemic markers of PNALD in preterm piglets. The addition of phytosterols to Omegaven did not produce evidence of PNALD. © 2015 American Society for Parenteral and Enteral Nutrition.JPEN. Journal of parenteral and enteral nutrition. 01/2015;
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ABSTRACT: Fibromyalgia syndrome (FMS) is characterized by musculoskeletal pain of unknown etiology and is often accompanied by many psychological symptoms. This study is aimed at evaluating the importance of antioxidants (vitamin E, vitamin C and Nigella sativa seeds) therapy in management of this disease. Fifty female patients having mean age of 37.87±1.68 years suffering from FM were enrolled in the study. Role of oxidative stress was determined by measuring antioxidant enzymes including superoxide dismutase (SOD), glutathione peroxidase (GPx), antioxidant capacity by ABTS (2,2’- azinobis-(3-ethylbenzo-thiazoline-6-sulphonic diammonium salt) and ferric reducing antioxidant capacity (FRAP) assay in plasma and catalase in erythrocytes. The FM patients were also supplemented with antioxidants (Vitamin C, Vitamin E and Nigella sativa seeds) for two months to assess the impact on activity of FM with the help of VAS (visual analogue scale) (0 being no pain and 100 being severe pain).It was found that FM patients had low activity of SOD, GPx and low antioxidant capacity (AOC) than healthy controls. It was further observed that after two months supplementation with antioxidants (vitamin C, vitamin E and Nigella sativa seeds) the level of SOD, GPx and AOC increased and their mean VAS 90.30±1.52 at baseline decreased to mean VAS of 77.80±1.65 after supplementation with antioxidants.The antioxidant supplementation for two months resulted in significant improvement in FM patients and it may help in minimizing the effects of the oxidativestress.Pakistan journal of zoology 01/2015; 47(1):7-13. · 0.40 Impact Factor