Beneficial Effects of Tocotrienol and Tocopherol on Bone Histomorphometric Parameters in Sprague–Dawley Male Rats After Nicotine Cessation

Abstract

This study was conducted to determine the effectiveness of three forms of vitamin E supplements following nicotine treatment on bone histomorphometric parameters in an adult male rat model. Rats were divided into seven groups: baseline (B, killed without treatment), control (C, normal saline for 4 months), nicotine (N, nicotine for 2 months), nicotine cessation (NC), tocotrienol-enhanced fraction (TEF), gamma-tocotrienol (GTT), and alpha-tocopherol (ATF). Treatments for the NC, TEF, GTT, and ATF groups were performed in two phases. For the first 2 months they were given nicotine (7 mg/kg), and for the following 2 months nicotine administration was stopped and treatments with respective vitamin E preparations (60 mg/kg) were commenced except for the NC group, which was allowed to recover without treatment. Rats in the N and NC groups had lower trabecular bone volume, mineral appositional rate (MAR), and bone formation rate (BFR/BS) and higher single labeled surface and osteoclast surface compared to the C group. Vitamin E treatment reversed these nicotine effects. Both the TEF and GTT groups, but not the ATF group, had a significantly higher trabecular thickness but lower eroded surface (ES/BS) than the C group. The tocotrienol-treated groups had lower ES/BS than the ATF group. The GTT group showed a significantly higher MAR and BFR/BS than the TEF and ATF groups. In conclusion, nicotine induced significant bone loss, while vitamin E supplements not only reversed the effects but also stimulated bone formation significantly above baseline values. Tocotrienol was shown to be slightly superior compared to tocopherol. Thus, vitamin E, especially GTT, may have therapeutic potential to repair bone damage caused by chronic smoking.

Gamma-Tocotrienol Stimulates the Proliferation, Differentiation, and Mineralization in Osteoblastic MC3T3-E1 Cells

“…However, 16 mol/L and above of -tocotrienol showed the toxicity to osteoblast cells. The results are consistent with previous studies [16,37] which demonstrate thattocotrienol, at low dosage, was better than -tocopherol in protecting rat osteoblasts against H 2 O 2 toxicity; but at high dosage it was toxic to osteoblasts in rats [16]. It may be caused by the fact that antioxidants, like -tocotrienol, at a certain dosage can become prooxidants [38].…”

“…In previous studies, tocotrienols have been shown to have better bone protective effects when compared to -tocopherol in animal osteoporosis models [13][14][15][16][17][18][19]. Furthermore, studies also showed that tocotrienols were able to prevent and even reverse osteoporosis in estrogen deficiency, testosterone deficiency, glucocorticoid excess, and nicotine exposure [15][16][17][20][21][22][23]. Previous study demonstrated that palm tocotrienol is even more effective than calcium in preventing bone loss caused by estrogen deficiency [24].…”

Effects of vitamin E on bone turnover markers among US postmenopausal women

“…Some studies suggest that alpha-tocopherol may improve bone quality and strength, (71,72) maintain BMD, (73) decrease bone resorption, (74) and increase bone formation. (75) Hypothesized mechanisms include preventing the accumulation of bone resorbing cytokines, (76) reducing the number of osteoclasts, (75) and increasing the number of osteoblasts. (75) Conversely, other studies suggest that alpha-tocopherol supplementation did not improve bone quality, BMD, or BTMs, (77,78) and in fact one study suggests that a high dose of vitamin E may have a detrimental effect on bone quality.…”

Quantification of Bone Histomorphometric Parameters Using the Weibel Technique in Animals

“…In general, sLS/BS parameter corresponds to poor bone formation while dLS/BS, MS/BS and MAR correspond to bone formation and mineralization. A vast amount of literature showed that the use of the Weibel technique is a very effective stereological test system and give reliable results on the analysis of bone static and dynamic histomorphometric parameters (Nazrun et al 2005;Shuid et al 2007;Hermizi et al 2009;Mehat et al 2010;Hermizi et al 2011;Aktifanus et al 2012;Fathilah et al 2012;Hussan et al 2012;Muhammad et al 2012;Soelaiman et al 2012;Abdul-Majeed et al 2012;Chin et al 2014;Parvaneh et al 2015). However, a detailed description of the protocol had not been mentioned.…”

“…Moreover, these studies used this technique to investigate the efficacy of antiosteoporotic therapies (Nazrun et al 2005;Shuid et al 2007;Hermizi et al 2009;Mehat et al 2010;Hermizi et al 2011;Aktifanus et al 2012;Fathilah et al 2012;Hussan et al 2012;Muhammad et al 2012;Abdul-Majeed et al 2012;Chin et al 2014;Parvaneh et al 2015). These studies have referred to (Weibel et al 1966;Freere & Weibel 1967) in performing the protocol without a detailed description on how did they evaluate the parameters.…”