Synthetic analogs of phytanic acid and their effect on human hepatic cholesterol esterase in vitro

Adult Refsum disease is an inherited disorder in which phytanic acid accumulates in tissues and serum. Two hypotheses have been proposed to explain the pathogenesis of this condition. The molecular distortion hypothesis suggests that phytanic acid may alter membrane composition and structure, thereby affecting membrane function(s). The anti-metabolite hypothesis suggests that an accumulation of phytanic acid in membranes may interfere with vitamin E function. These two hypotheses were investigated by studying the effects of modulating phytanic acid and α-tocopherol concentrations on the fatty acid composition and certain physical parameters of cultured retinal cells. Results showed that (a) the phospholipid fraction of retinal cells readily incorporated phytanic acid, (b) the incorporation of phytanic acid increased membrane fluidity, (c) there was no competition for uptake between phytanic acid and α-tocopherol, and (d) the incorporation of phytanic acid did not increase the susceptibility of membranes to lipid peroxidation in vitro. These results obtained with cultured retinal cells suggest that the molecular distortion hypothesis, but not the anti-metabolite hypothesis, could explain the pathogenesis of adult Refsum disease. In vitro tissue culture models can, however, only approximate to the much more complex situation that occurs in vivo.

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Bark Extracts of Ceylon Cinnamon Possess Antilipidemic Activities and Bind Bile Acids In Vitro

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2017/7347219 ◽

2017 ◽

Vol 2017 ◽

pp. 1-10 ◽

Cited By ~ 5

Author(s):

Walimuni Prabhashini Kaushalya Mendis Abeysekera ◽

Sirimal Premakumara Galbada Arachchige ◽

Wanigasekera Daya Ratnasooriya

Keyword(s):

Bile Acids ◽

Scientific Evidence ◽

Ethanol Extract ◽

Cholesterol Esterase ◽

Hmg Coa Reductase ◽

Cinnamon Bark ◽

Ceylon Cinnamon ◽

Inhibitory Activities ◽

Coa Reductase

Ethanol (95%) and dichloromethane : methanol (1 : 1) bark extracts of authenticated Ceylon cinnamon were investigated for range of antilipidemic activities (ALA): HMG-CoA reductase, lipase, cholesterol esterase, and cholesterol micellization inhibitory activities and bile acids binding in vitro. Individual compounds in bark extracts were also evaluated. Bark extracts showed ALA in all the assays studied. The IC50 (μg/mL) values ranged within 153.07±8.38–277.13±32.18, 297.57±11.78–301.09±4.05, 30.61±0.79–34.05±0.41, and 231.96±9.22–478.89±9.27, respectively, for HMG-CoA reductase, lipase, cholesterol esterase, and cholesterol micellization inhibitory activities. The bile acids binding (3 mg/mL) for taurocholate, glycodeoxycholate, and chenodeoxycholate ranged within 19.74±0.31–20.22±0.31, 21.97±2.21–26.97±1.61, and 16.11±1.42–19.11±1.52%, respectively. The observed ALA were moderate compared to the reference drugs studied. Individual compounds in bark extracts ranged within 2.14±0.28–101.91±3.61 and 0.42±0.03–49.12±1.89 mg/g of extract. Cinnamaldehyde and gallic acid were the highest and the lowest among the tested compounds. The ethanol extract had highest quantity of individual compounds and ALA investigated. Properties observed indicate usefulness of Ceylon cinnamon bark in managing hyperlipidemia and obesity worldwide. Further, this study provides scientific evidence for the traditional claim that Ceylon cinnamon has antilipidemic activities.

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