Long-chain SFA at thesn-1, 3 positions of TAG reduce body fat deposition in C57BL/6 mice

Abstract

The present study aimed to determine the effect of positional distribution of long-chain SFA in TAG, especially at the sn-1, 3 positions, on fat deposition using the C57BL/6 mouse model. Throughout the 15 weeks of the study, mice were fed with diets fortified with palm olein (POo), chemically interesterified POo (IPOo) and soyabean oil (SOY). Mice receiving the SOY-enriched diet gained significantly higher amounts of subcutaneous fat (P¼0·011) and total fat (P¼ 0·013) compared with the POo group, despite similar body mass gain being recorded. During normalisation with food consumption to obtain the fat:feed ratio, mice fed with the POo-enriched diet exhibited significantly lower visceral (P¼ 0·044), subcutaneous (P¼ 0·006) and total (P¼ 0·003) fat:feed than those fed with the SOY-enriched diet. It is noteworthy that mice fed with the IPOo-enriched diet gained 14·3 % more fat per food consumed when compared with the POo group (P¼0·013), despite their identical total fatty acid compositions. This was mainly attributed to the higher content of longchain SFA at the sn-1, 3 positions of TAG in POo, which results in delayed absorption after deacylation as evidenced by the higher amounts of long-chain SFA excreted in the faeces of mice fed with the POo-enriched diet. Negative correlations were found between the subcutaneous, visceral as well as total fat accretion per food consumption and the total SFA content at the sn-1, 3 positions, while no relationships were found for MUFA and PUFA. The present results show that the positional distribution of long-chain SFA exerts a more profound effect on body fat accretion than the total SFA content.

Effect of sex, dietary glycerol or dietary fat during late fattening, on fatty acid composition and positional distribution of fatty acids within the triglyceride in pigs

“…Most of the C16:0 present in lard is located in the internal (Sn-2) position whereas, in palm oil it locates in the external (Sn-1 and Sn-3) positions (Small, 1991;Innis, 2011). This difference might be relevant in further processing for the industry of dry-cured products because FA distribution within the TAG molecule modifies the physical properties of the adipose tissue (Smith et al, 1998;Segura et al, 2015) and might affect the incidence of human illnesses such as obesity, diabetes or hypertension (Ponnampalam et al, 2011;Gouk et al, 2013).…”

Shea butter

“…In their review of the dietary effects of saturated fats, German and Dillard (2004) also state stearic acid is not thought to increase cholesterol concentrations and also discuss the importance of the TAG positions of the stearic acid groups on the molecule. Further evidence, from studies on mice metabolism, in support of both positional effects and of the role of stearic over palmitic acid in reducing fat deposition is offered by Gouk et al (2013Gouk et al ( , 2014. In the presence of calcium it is then poorly absorbed.…”

Incorporation of Palmitic Acid or Stearic Acid into Soybean Oils Using Enzymatic Interesterification

“…Hence, fatty acid distribution cannot be predicted before CIE, thus the application of end products from CIE will be hardly categorized as specific type of oils. Gouk and co-workers found that long chain fatty acids at sn-1,3 positions exhibited more profound effect in reducing body fat deposition in mice rather than total fatty acid compositions sn-1,2,3 8,9 because the snposition in the TG molecule determines the physical characteristic of fats, affects the absorption of fatty acids, lipid metabolism and fat distribution in tissues 10 . Previous studies indicated that unsaturated fatty acids at 2-position of triglycerides play an important role in regulating cholesterol levels in the bloodstream 11,12 .…”