{'fraction_non_alphanumeric': 0.053918495297805645, 'fraction_numerical': 0.04326018808777429, 'mean_word_length': 4.867647058823529, 'pattern_counts': {'":': 0, '<': 6, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Phytosterols induce changes in hepatic protein expression patterns and increase cholesterol biosynthesis and sterol efflux in a hypercholesterolemic animal model

Although phytosterols (PS) modulate intestinal cholesterol metabolism, the role of PS on hepatic sterol trafficking is not known. The objective of this study was to identify hepatic molecular targets responding to oral PS in hamsters (n = 8) fed 0.25% cholesterol diets with or without 2% PS for 28 d. Consumption of PS reduced (P<0.002) plasma total cholesterol (7.8±0.5 vs. 5.3±0.4 mmol/L) vs control. Increased hepatic sterol efflux was suggested by higher LXRβ (P = 0.06, 1.4 fold of control) and ABCG5 (P<0.03, 1.4 fold of control) expression. High sterol fecal output was obersved in PS fed animals. A compensatory increase in fractional absorption of [3, 4]‐13C cholesterol (67.5‰ vs 47.6‰; P<0.02) and 3.7 fold increase (P=0.02) in fractional cholesterol synthesis was also noted in PS animals. Similarly, PS increased (P<0.01) HMGCoA‐R expression to 1.4 fold of control. While PS increased the cytosolic precursor form of SREBP2 (P<0.001) by 3.9 fold, the nuclear active form of SREBP2 was reduced (P<0.005) 2.4 fold relative to control, confirmed in vitro in HepG2 cells treated with PS. This differential regulation might reflect high intracellular levels of both C synthesis intermediates and PS, thereby interfering with normal SREBP2 processing. These data confirm that PS directly affects the expression of hepatic proteins regulating cholesterol trafficking, important for lowering blood cholesterol. Funding: NSERC.