Oligomeric Procyanidins in Apple Polyphenol Are Main Active Components for Inhibition of Pancreatic Lipase and Triglyceride Absorption

Abstract

Inhibitory effects of apple polyphenol extract (AP) and procyanidin contained in AP on in vitro pancreatic lipase activity and in vivo triglyceride absorption in mice and humans were examined. AP and procyanidin considerably inhibited in vitro pancreatic lipase activity. However, polyphenols, except for procyanidin, in AP (i.e., catechins, chalcones, and phenol carboxylic acids) showed weak inhibitory activities on pancreatic lipase. Procyanidins separated by normal-phase chromatography according to the degree of polymerization were also examined. Inhibitory effects of procyanidins increased according to the degree of polymerization from dimer to pentamer. On the other hand, pentamer or greater procyanidins showed maximal inhibitory effects on pancreatic lipase. These results suggested that with respect to in vitro pancreatic lipase inhibition, the degree of polymerization was an important factor and oligomeric procyanidin mainly contributed. Next, we performed a triglyceride tolerance test in mice and humans. Simultaneous ingestion of AP and triglyceride significantly inhibited an increase of plasma triglyceride levels in both models. These results suggested that the oligomeric procyanidins contained in AP inhibited triglyceride absorption by inhibiting pancreatic lipase activity in mice and humans.

The lipid-lowering effect of dietary proanthocyanidins in rats involves both chylomicron-rich and VLDL-rich fractions

“…The present results show that the oral intake of GSPE significantly blocked the increase in plasma TAG levels induced by lard oil ingestion in control animals. This blockade of plasma TAG has also been described with PA from apples (8) in mice loaded with maize oil, in which the blockade was as rapid as that observed in the present experiment (1 h). In the present study, the reduction in plasma TAG levels was similar to the reductions observed in male normolipidaemic rats (6) and mice (10,11) after performing acute GSPE treatment and in dyslipidaemic rats (7) after performing chronic GSPE treatment.…”

“…Therefore, PA repress the secretion of both synthesised, endogenous TAG and TAG absorbed from the diet. Several authors have reported that CM and lipid absorption cause the hypolipidaemic actions of PA, but only on the basis of indirect evidence or in vitro experiments (8,9) . The expression of the selected genes related to FA and TAG metabolism as well as those of the CM assembly was not modified in the intestinal mucosa at 1 or 5 h after GSPE administration.…”

“…The hypolipidaemic action of grape seed proanthocyanidin extract (GSPE) is attributable to a reduction in plasma levels of TAG-rich lipoproteins and to an improvement of the serum cholesterol profile, both in normolipidaemic (6) and dyslipidaemic rats (7) . Additionally, the simultaneous ingestion of apple PA with fat inhibits the increase in plasma TAG levels induced by fat ingestion in mice and human subjects (8) .Plasma TAG levels are the result of the balance between TAG-rich lipoprotein secretion by the intestine and liver and its uptake by the extrahepatic tissues through lipoprotein lipase (LPL). TAG-rich lipoproteins in plasma originate in either the liver (VLDL) or the intestine (chylomicrons, CM).…”

Comparison of in vitro anti-lipase and antioxidant activities, and composition of commercial chokeberry juices

“…Reduced absorption of dietary fat from the intestine by the inhibition of digestive lipases, especially pancreatic lipase, is an approach to decreasing the risk of obesity [15]. The presence of pancreatic lipase inhibitors has recently been reported in some edible fruits, including black chokeberry [12,13,21,[25][26][27][28][29]. Inhibition of this enzyme by fruits is attributed to the phenolic compounds, such as proanthocyanidins [12,21,27], ellagitannins [25,26], anthocyanins [13,28], and flavones [29].…”

“…The mDP of proanthocyanidins occurring in chokeberry fruit was determined as 59 [36] or in the acetone fruit extract as 19 [34]. The published studies have shown that anti-lipase activity of proanthocyanidins depends upon the degree of polymerization and more potent effect was observed for higher DP [27,37]. For example, the IC 50 values determined with the use of 4-MUO as the substrate were as follows: for dimer >125 μg/ml, but 32.9 and only 0.9 μg/ml for trimer and procyanidins over nonamer, respectively [27].…”