Effect of Rare Earth Elements on Proliferation and Fatty Acids Accumulation of 3T3-L1 Cells

M L He,W A Rambeck,W Z Yang,H Hidari

doi:10.5713/ajas.2006.119

Abstract

The present study including two experiments was designed to determine the effect of media containing different rare earth elements (REE) on proliferation and fatty acids accumulation in 3T3-L1 cell cultures. In Experiment 1, 3T3-L1 preadipocytes in 96-well plates (1.5×10 4 cells/ml) were cultured with Dulbecco's modified Eagle's medium (DMEM) containing 10% fetal bovine serum (FBS) for 24 h. Then the media were changed to the following 10 different media for 48 h: DMEM containing 10% FBS for the control; the above media containing 5 µM, 10 µM or 15 µM of LaCl3, CeCl3 or the mixture of these REE chlorides. The proliferation rate of the cells was measured and compared by a non-isotope method-XTT method. In Experiment 2 the cells in 24-well plates (1.5×10 4 cells/ml) were cultured in DMEM containing 10% FBS for 7 days until confluent and then were changed to above DMEM containing dexamethasone, methyl-isobutylxanthine and insulin (DMI) for two days. Afterwards the media were changed to the 10 different media with REE supplements as in Experiment 1 and cultured for 6 days. The cells were then harvested for fatty acids analysis by gas chromatography. It was found that supplementation of La (5, 10 and 15 µM), Ce (5 µM and 15 µM) and the mixture REE (5, 10 and 15 µM) stimulated (p<0.05) the proliferation of 3T3-L1 preadipocytes (Experiment 1). In the differentiating 3T3-L1 cells supplementation of La (5 µM and 10 µM), Ce (5 µM) and the mixture REE (5 µM and 15 µM) decreased (p<0.05) the concentration of monounsaturated fatty acids (MUFA) per 10 5 cells, while the supplementation of La (5 µM), Ce (5 µM) and the mixture REE (15 µM) increased (p<0.05) the ratio of saturated fatty acids (SFA) to MUFA. These results indicate that the supplementation of REE to the media may affect proliferation, differentiation and lipogenesis rates of 3T3-L1 cells. However, the effect may depend upon the level or type of REE applied. (Asian-Aust. J. Anim. Sci. 2006. Vol 19, No. 1 : 119-125)

Highlights

Rare earth elements (REE) including Lanthanum (La), Cerium (Ce) and other lanthanides are a group of elements with a lot of similarities in chemical and biochemical characters
The supplementation with micromoles of REE ions to the media significantly increased the proliferation of 3T3L1 preadipocytes (Experiment 1), which was consistent with those reported by Smith and Smith (1984) that La ions stimulated the arrested Swiss 3T3 and 3T6 cells in G1/G0 phase to the S phase in the cell cycle
It was found that calcium formed in the membrane surface during 3T3 cells approach quiescence (Tupper and Zorgniotti, 1977; Smith and Smith, 1984)

Summary

Introduction

Rare earth elements (REE) including Lanthanum (La), Cerium (Ce) and other lanthanides are a group of elements with a lot of similarities in chemical and biochemical characters. The REE have been used as a kind of feed additive in animal production in China for years. The supplementation of REE to the diet improved the daily body weight gain or feed conversion ratio in the growing animals. A very small amount of REE could be absorbed into body when they were supplemented orally (He and Rambeck, 2000). Such small amount (micromoles) of REE in animal body may have effect on the metabolism through influence the hormones such as triiodothyronine (He et al, 2003) or growth hormone (Wang and Xu, 2003). There are some early studies on effect of REE in animal tissues and cells (Evans, 1990), little information was available on their effect on animal adipose tissues or development of adipocytes

Methods

Results

Conclusion