Relationship between aorta cholesterol content and plasma lipids in guinea pigs fed an atherogenic diet

1. Pregnant guinea-pigs receiving a low dose of L-ascorbic acid (0.2 mg/100 g body-weight per d) developed a hypercholesterolaemia in the third trimester of pregnancy, whereas no change in serum cholesterol levels was observed in pregnant animals receiving a higher dose of the vitamin (2 mg/100 g body-weight per d).2. Pregnancy in the group of guinea-pigs receiving the higher dose of L-ascorbic acid was associated with an increased biliary secretion of bile acids. No change was observed in the biliary secretion of bile acids in pregnant animals receiving the lower dose of L-ascorbic acid, but these animals secreted significantly more cholesterol.3. Changes in the biliary secretion of cholesterol and bile acids in the pregnant guinea-pig according to L-ascorbic acid intake were reflected in the composition of the gall-bladder bile. Thus, the gall-bladder bile of guinea-pigs receiving the lower dose of L-ascorbic acid contained more cholesterol, while the gall-bladder bile of those animals receiving the higher dose of the vitamin had a higher content of bile acids.4. The increased cholesterol content of the gall-bladder of pregnant guinea-pigs receiving the lower dose of L-ascorbic acid resulted in decreased bile acid:cholesterol and phospholipid: cholesterol values, conditions predisposing to cholelithiasis.

Download Full-text

High dietary fat and cholesterol exacerbates chronic vitamin C deficiency in guinea pigs

British Journal Of Nutrition ◽

10.1017/s0007114510003077 ◽

2010 ◽

Vol 105 (1) ◽

pp. 54-61 ◽

Cited By ~ 23

Author(s):

Henriette Frikke-Schmidt ◽

Pernille Tveden-Nyborg ◽

Malene Muusfeldt Birck ◽

Jens Lykkesfeldt

Keyword(s):

Vitamin C ◽

Guinea Pigs ◽

Cholesterol Content ◽

Dietary Lipid ◽

Western World ◽

High Fat ◽

Vitamin C Deficiency ◽

Increased Risk ◽

Oxidation Ratio ◽

The Brain

Vitamin C deficiency – or hypovitaminosis C defined as a plasma concentration below 23 μm – is estimated to affect hundreds of millions of people in the Western world, in particular subpopulations of low socio-economic status that tend to eat diets of poor nutritional value. Recent studies by us have shown that vitamin C deficiency may result in impaired brain development. Thus, the aim of the present study was to investigate if a poor diet high in fat and cholesterol affects the vitamin C status of guinea pigs kept on either sufficient or deficient levels of dietary ascorbate (Asc) for up to 6 months with particular emphasis on the brain. The present results show that a high-fat and cholesterol diet significantly decreased the vitamin C concentrations in the brain, irrespective of the vitamin C status of the animal (P < 0·001). The brain Asc oxidation ratio only depended on vitamin C status (P < 0·0001) and not on the dietary lipid content. In plasma, the levels of Asc significantly decreased when vitamin C in the diet was low or when the fat/cholesterol content was high (P < 0·0001 for both). The Asc oxidation ratio increased both with low vitamin C and with high fat and cholesterol content (P < 0·0001 for both). We show here for the first time that vitamin C homoeostasis of brain is affected by a diet rich in fat and cholesterol. The present findings suggest that this type of diet increases the turnover of Asc; hence, individuals consuming high-lipid diets may be at increased risk of vitamin C deficiency.

Download Full-text

High-Dose Ascorbic Acid Decreases Cholesterolemic Factors of an Atherogenic Diet in Guinea Pigs

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831.77.2.125 ◽

2007 ◽

Vol 77 (2) ◽

pp. 125-129

Author(s):

Filis ◽

Anastassopoulou ◽

Sigala ◽

Theodorou ◽

Manouras ◽

...

Keyword(s):

Ascorbic Acid ◽

Guinea Pigs ◽

Low Dose ◽

Plasma Concentrations ◽

Atherogenic Diet ◽

High Dose ◽

Low Density ◽

Group Iii ◽

Group I ◽

Group Ii

Background: The study evaluates the effect of a high supplemental dose of ascorbic acid (AA) on plasma concentrations of total cholesterol (TC), triglycerides (TG), total lipids (TL), and lipoprotein fractions high-density, very-low-density-, and low-density lipoprotein (HDL, VLDL, LDL) in guinea pigs fed with atherogenic diet. Methods: Group I consisted of 5 normally fed guinea pigs plus a low dose of AA (1 mg/100 g/day), group II consisted of 7 guinea pigs fed with food enriched with 2% cholesterol plus a low dose of AA (1 mg/100 g/day), and group III consisted of 7 guinea pigs fed with food enriched with 2% cholesterol plus a high dose of AA (30 mg/100 g/day). Cholesterolemic factors concentrations were determined after nine weeks. Results: Concentrations of TC, TG, TL, LDL, and VLDL were increased in group II compared to group I (p < 0.01 for all differences). Supplementation with a high dose of AA resulted in decreased concentrations of TC (p < 0.01), TG (p < 0.01), TL (p < 0.01), and LDL (p < 0.01) in group III compared to group II. Additionally, concentration of HDL was increased in group III compared to group II (p < 0.01). Conclusion: High-dose AA supplementation to an atherogenic diet decreases concentrations of TC, TG, TL, and LDL and increases concentration of HDL compared to low-dose AA.

Download Full-text