Marginal Zinc Deficiency Lowers the Lymphatic Absorption of α-Tocopherol in Rats ,

Abstract

The present study was conducted to investigate whether the intestinal absorption of vitamin E is influenced by marginal zinc deficiency. Rats trained to meal feed were divided into two groups and fed a diet containing 3 mg Zn/kg [a low zinc (LZ group)] or pair-fed (PF controls a zinc-adequate diet (30 mg Zn/kg). At 5 wk, the body weight (352 +/- 5 g, mean +/- SD) of LZ rats was 98.5% of that of PF rats (357 +/- 8 g). Rats with lymph cannula were infused at 3 mL/h via a duodenal catheter with a lipid emulsion consisting of 568 micromol triolein, 3.56 micromol alpha-tocopherol (alphaTP) and 396 micromol Na+-taurocholate in 24 mL of phosphate-buffered saline (pH 6.4). Lymph was collected hourly for 8 h. The amounts of alphaTP absorbed into the lymph were determined by high-performance liquid chromatography (HPLC). The hourly rate of alphaTP absorption was significantly lower in LZ than in PF rats. A marked difference (P < 0.05) was clearly evident even at 1 h (1.8 +/- 1.2 nmol/h in LZ vs. 8.5 +/- 3.0 nmol/h in PF). The peak rate of absorption was significantly lower in LZ rats (67.1 +/- 16.7 nmol/h at 5 h) than in PF rats (95.9 +/- 7.7 nmol/h at 4 h). The total amounts of alphaTP absorbed in 8 h in LZ and PF rats were 391.1 +/- 54.4 nmol (11.0 +/- 1.5% dose) and 613.9 +/- 105.8 nmol (17.2 +/- 3.0% dose), respectively. The lymphatic absorption of alphaTP was correlated with the amounts of PL (r = 0.77, P < 0.05) released into the mesenteric lymph. The hourly outputs of phospholipid and oleic acid also were significantly lower in LZ rats than in PF rats up to 4 h (P < 0.05). The cumulative lymphatic outputs of phospholipid (PL) were 20.1 +/- 3.7 micromol/8 h in LZ and 27.0 +/- 3.9 micromol/8 h in PF rats (P < 0.05). These results show that the intestinal absorption of vitamin E is affected by the zinc status of rats. This observation along with our earlier finding of a lower intestinal absorption of retinol suggests that zinc nutriture has a profound effect on the intestinal absorption and body status of lipid soluble vitamins.

Effect of Zinc Supplementation on Antioxidant Defenses and Oxidative Stress Markers in Patients Undergoing Chemotherapy for Colorectal Cancer: a Placebo-Controlled, Prospective Randomized Trial

“…Interestingly, plasma vitamin E remained unaltered in our patients receiving zinc supplementation during chemotherapy. The nature of the interaction between zinc and vitamin E status has not been clearly defined [34]. In this study, the increased SOD activity and the presumably elevated metallothionein concentration resulting from zinc supplementation may have counterbalanced the oxidative environment, leading to maintenance of plasma vitamin E concentrations.…”

“…In this study, the increased SOD activity and the presumably elevated metallothionein concentration resulting from zinc supplementation may have counterbalanced the oxidative environment, leading to maintenance of plasma vitamin E concentrations. Also, lymphatic absorption of vitamin E is affected by zinc status [34] and zinc deficiency lowers plasma vitamin E concentration in rats [35]. After zinc supplementation, hemodialysis patients had higher plasma vitamin E concentrations compared with patients not receiving supplementation [11].…”

Effects of Dietary Copper and Zinc Supplementation on Growth Performance, Tissue Mineral Retention, Antioxidant Status, and Fur Quality in Growing-Furring Blue Foxes (Alopex lagopus)

“…Additionally, a high Zn addition improved the utilization of fat, which may be similar to the action mode of Cu by improving lipase activity. Phospholipase A 2 is a Zn-dependent digestive enzyme secreted in the pancreas [33]. It hydrolyzes phosphatidylcholine, facilitating its absorption and the formation of chylomicrons, which are crucial for the absorption of fat micelles [34].…”

Serum antioxidants and trace minerals as influenced by vitamins, probiotics and proteins in broiler breeders

“…The exact mechanism of the Zn anti-oxidative role is still vague; however, it is speculated that Zn scavenges free radicals by increased synthesis of metallothionein (Oteiza et al 1996). One way of the mechanism of action of this mineral is its role as an anti-oxidant through its interaction with vitamin E, the synthesis of which is impaired in Zn deficiency (Kim et al 1998;Prasad & Kucuk 2002). Zn may play a role in suppressing the creation of free radicals, as it is a substantial part of the anti-oxidative enzyme copperÁ zinc superoxide dismustase (Khan 2011).…”