Ascorbic acid inhibits the increase in low-density lipoprotein (LDL) susceptibility to oxidation and the proportion of electronegative LDL induced by intense aerobic exercise.

[Guest guest]

Hi All,

In this paper it is shown that aerobic exercise does increase oxidized LDL and

that the use of 1 g of Vit C before the

activity eliminates the normal increase in oxidized LDL which results from the

increased free radical load generated by

the exercise.

Note the conclusions.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve & db=PubMed & list_uids=9\

710684 & dopt=Abstract

Coron Artery Dis 1998;9(5):249-55 Related Articles, Books, LinkOut

Ascorbic acid inhibits the increase in low-density lipoprotein (LDL)

susceptibility to oxidation and the proportion of

electronegative LDL induced by intense aerobic exercise.

-Quesada JL, Jorba O, Payes A, Otal C, Serra-Grima R, -Sastre F,

Ordonez-Llanos J.

Servei de Bioquimica, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.

BACKGROUND:

We have previously reported the finding of an acute increment in the

susceptibility of low-density lipoprotein (LDL) to

oxidation and in the proportion of electronegative LDL [LDL(-)] after intense

exercise. We have now studied the effect

of oral supplementation with 1 g ascorbic acid, immediately before a 4-h

athletic race, on the susceptibility of LDL to

oxidation, the proportion of LDL(-), and the alpha-tocopherol and lipid

peroxides content in LDL, in order to inhibit

such deleterious changes, and to confirm the oxidative nature of modifications

of LDL induced by exercise.

METHODS:

We studied seven highly trained runners who received a supplement of 1 g

ascorbic acid and a control group of seven who

did not receive the supplement. The susceptibility of LDL to oxidation was

assessed by measurement of conjugated dienes

after CuSO4-induced oxidation, the proportion of LDL(-) was determined by anion

exchange chromatography,

alpha-tocopherol was quantified by reverse-phase high performance liquid

chromatography, and lipid peroxides were

measured by the thiobarbituric acid-reactive substances (TBARS) method.

RESULTS:

After exercise, in the control group there was an increase in both the

susceptibility of LDL to oxidation (change in lag

phase from 51.4 +/- 4.7 min to 47.0 +/- 4.6 min, P < 0.05) and the proportion of

LDL(-) (from 11.1 +/- 1.4% to 13.0 +/-

2.2%, P < 0.05), but these did not occur in the ascorbic acid group (change in

lag phase from 49.7 +/- 2.3 min to 50.4

+/- 4.2 min, and in LDL(-) from 9.7 +/- 1.7% to 10.1 +/- 1.7%). No significant

changes in the absolute amount of LDL

alpha-tocopherol were observed after exercise (ascorbic acid group: 6.65 +/-

0.94 mol/mol apoB before the race, 7.13 +/-

0.88 mol/mol apoB after the race; control group: 7.34 +/-0.69 mol/mol apoB

before the race, 7.06 +/- 0.69 mol/mol apoB

after the race), but significant differences were found when increments or

decrements of alpha-tocopherol were tested

(alpha-tocopherol increased 9.9 +/- 11.5% in the ascorbic acid group, and

decreased 0.6 +/- 7.3% in the control group; P

< 0.018). TBARS did not change after exercise.

CONCLUSIONS:

We conclude that 1 g ascorbic acid inhibits the increase in LDL susceptibility

to oxidation after exercise, preventing

this acute pro-atherogenic effect. In addition, the observation that LDL(-)

enhancement is prevented by ascorbic acid

supports the hypothesis that at least some of the circulating LDL(-) originates

from oxidative processes.

PMID: 9710684 [PubMed - indexed for MEDLINE]

========================

Good Health & Long Life,

Greg , http://optimalhealth.cia.com.au gowatson@...

USDA database (food breakdown) http://www.nal.usda.gov/fnic/foodcomp/

PubMed (research papers) http://www.ncbi.nlm.nih.gov/entrez/query.fcgi

DWIDP (nutrient analysis) http://www.walford.com/dwdemo/dw2b63demo.exe

Patch file for above http://www.walford.com/download/dwidp67u.exe

KIM (omega analysis) http://ods.od.nih.gov/eicosanoids/KIM_Install.exe

[Guest guest]

Before you run right out and get your vit C, please be aware that some

people will reach their bowel intolerance at 1 Gram or 1000 millegrams. In

other words, if you start to experience gas and bloating or loose stools

it's due to the Vit C. This is so especially for the good Vit C. CB

Ascorbic acid inhibits the increase in low-density

lipoprotein (LDL) susceptibility to oxidation and the proportion of

electronegative LDL induced by intense aerobic exercise.

> Hi All,

>

> In this paper it is shown that aerobic exercise does increase oxidized LDL

and that the use of 1 g of Vit C before the

> activity eliminates the normal increase in oxidized LDL which results from

the increased free radical load generated by

> the exercise.

>

> Note the conclusions.

>

>

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve & db=PubMed & list_ui

ds=9710684 & dopt=Abstract

> Coron Artery Dis 1998;9(5):249-55 Related Articles, Books, LinkOut

> Ascorbic acid inhibits the increase in low-density lipoprotein (LDL)

susceptibility to oxidation and the proportion of

> electronegative LDL induced by intense aerobic exercise.

> -Quesada JL, Jorba O, Payes A, Otal C, Serra-Grima R,

-Sastre F, Ordonez-Llanos J.

> Servei de Bioquimica, Hospital de la Santa Creu i Sant Pau, Barcelona,

Spain.

>

> BACKGROUND:

> We have previously reported the finding of an acute increment in the

susceptibility of low-density lipoprotein (LDL) to

> oxidation and in the proportion of electronegative LDL [LDL(-)] after

intense exercise. We have now studied the effect

> of oral supplementation with 1 g ascorbic acid, immediately before a 4-h

athletic race, on the susceptibility of LDL to

> oxidation, the proportion of LDL(-), and the alpha-tocopherol and lipid

peroxides content in LDL, in order to inhibit

> such deleterious changes, and to confirm the oxidative nature of

modifications of LDL induced by exercise.

>

> METHODS:

> We studied seven highly trained runners who received a supplement of 1 g

ascorbic acid and a control group of seven who

> did not receive the supplement. The susceptibility of LDL to oxidation was

assessed by measurement of conjugated dienes

> after CuSO4-induced oxidation, the proportion of LDL(-) was determined by

anion exchange chromatography,

> alpha-tocopherol was quantified by reverse-phase high performance liquid

chromatography, and lipid peroxides were

> measured by the thiobarbituric acid-reactive substances (TBARS) method.

>

> RESULTS:

> After exercise, in the control group there was an increase in both the

susceptibility of LDL to oxidation (change in lag

> phase from 51.4 +/- 4.7 min to 47.0 +/- 4.6 min, P < 0.05) and the

proportion of LDL(-) (from 11.1 +/- 1.4% to 13.0 +/-

> 2.2%, P < 0.05), but these did not occur in the ascorbic acid group

(change in lag phase from 49.7 +/- 2.3 min to 50.4

> +/- 4.2 min, and in LDL(-) from 9.7 +/- 1.7% to 10.1 +/- 1.7%). No

significant changes in the absolute amount of LDL

> alpha-tocopherol were observed after exercise (ascorbic acid group: 6.65

+/- 0.94 mol/mol apoB before the race, 7.13 +/-

> 0.88 mol/mol apoB after the race; control group: 7.34 +/-0.69 mol/mol apoB

before the race, 7.06 +/- 0.69 mol/mol apoB

> after the race), but significant differences were found when increments or

decrements of alpha-tocopherol were tested

> (alpha-tocopherol increased 9.9 +/- 11.5% in the ascorbic acid group, and

decreased 0.6 +/- 7.3% in the control group; P

> < 0.018). TBARS did not change after exercise.

>

> CONCLUSIONS:

> We conclude that 1 g ascorbic acid inhibits the increase in LDL

susceptibility to oxidation after exercise, preventing

> this acute pro-atherogenic effect. In addition, the observation that

LDL(-) enhancement is prevented by ascorbic acid

> supports the hypothesis that at least some of the circulating LDL(-)

originates from oxidative processes.

>

> PMID: 9710684 [PubMed - indexed for MEDLINE]

>

> ========================

> Good Health & Long Life,

> Greg , http://optimalhealth.cia.com.au gowatson@...

> USDA database (food breakdown) http://www.nal.usda.gov/fnic/foodcomp/

> PubMed (research papers) http://www.ncbi.nlm.nih.gov/entrez/query.fcgi

> DWIDP (nutrient analysis) http://www.walford.com/dwdemo/dw2b63demo.exe

> Patch file for above http://www.walford.com/download/dwidp67u.exe

> KIM (omega analysis)

http://ods.od.nih.gov/eicosanoids/KIM_Install.exe

>

>

>

>

>