Epigallocatechin gallate concomitantly increases the low density lipoprotein receptor and the CD36 protein in the liver of hypercholesterolaemic rabbits

Paul D. Roach, Nenad NAUMOVSKI, Shipman Kristy, Rick Thorne

Research output: Contribution to journalMeeting Abstract

14 Citations (Scopus)

Abstract

Background – Epigallocatechin gallate (EGCG) is a major green tea catechin which is related to the reduction of
plasma cholesterol in animal models possibly through inhibition of cholesterol synthesis. Consistent with this, in
vitro studies have shown EGCG to be a non-competitive inhibitor of squalene epoxidase (1). In vivo, inhibition of
squalene epoxidase could be expected to reduce, relative to squalene, the amount of lathosterol produced; lathosterol
is a cholesterol precursor which is produced after squalene in the cholesterol synthetic pathway.
Objective – To determine the effect of EGCG on lathosterol relative to squalene in the hypercholesterolaemic
rabbit.
Design – New Zealand White rabbits (n=12) were fed a rabbit chow with 0.25% (w/w) cholesterol for 2 weeks to
render them hypercholesterolaemic. This was followed by a 4-week treatment period during which the control group
(n=6) remained on the 0.25% (w/w) cholesterol diet while the treatment group (n=6) was fed the same diet plus 2%
(w/w) EGCG added. Serum cholesterol (enzymatic), lathosterol (GC) and squalene (HPLC) were measured.
Outcomes – After the 4-week treatment period, serum lathosterol was significantly reduced in the treatment group
compared to control (P=0.03) but the serum squalene did not differ between the groups (P=0.46). Therefore, the
serum lathosterol to squalene ratio, a novel index of cholesterol synthesis, was significantly lower in the treatment
group compared to control (P=0.03). The EGCG treatment also reduced serum cholesterol by 85% (P=0.02).
Conclusions – These in vivo results support the in vitro observation that EGCG is an inhibitor of sqalene epoxidase.
Original languageEnglish
Pages (from-to)55
Number of pages1
JournalAsia Pacific Journal of Clinical Nutrition
Volume17
Issue numberSuppl 3
Publication statusPublished - 2008
Externally publishedYes

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CD36 Antigens
LDL Receptors
Squalene
Cholesterol
Rabbits
Liver
Serum
Squalene Monooxygenase
Diet
epigallocatechin gallate
Catechin
Tea
Animal Models
High Pressure Liquid Chromatography
Observation
lathosterol

Cite this

@article{7ba4c19df3ea4723ac4a60d17d7c8729,
title = "Epigallocatechin gallate concomitantly increases the low density lipoprotein receptor and the CD36 protein in the liver of hypercholesterolaemic rabbits",
abstract = "Background – Epigallocatechin gallate (EGCG) is a major green tea catechin which is related to the reduction ofplasma cholesterol in animal models possibly through inhibition of cholesterol synthesis. Consistent with this, invitro studies have shown EGCG to be a non-competitive inhibitor of squalene epoxidase (1). In vivo, inhibition ofsqualene epoxidase could be expected to reduce, relative to squalene, the amount of lathosterol produced; lathosterolis a cholesterol precursor which is produced after squalene in the cholesterol synthetic pathway.Objective – To determine the effect of EGCG on lathosterol relative to squalene in the hypercholesterolaemicrabbit.Design – New Zealand White rabbits (n=12) were fed a rabbit chow with 0.25{\%} (w/w) cholesterol for 2 weeks torender them hypercholesterolaemic. This was followed by a 4-week treatment period during which the control group(n=6) remained on the 0.25{\%} (w/w) cholesterol diet while the treatment group (n=6) was fed the same diet plus 2{\%}(w/w) EGCG added. Serum cholesterol (enzymatic), lathosterol (GC) and squalene (HPLC) were measured.Outcomes – After the 4-week treatment period, serum lathosterol was significantly reduced in the treatment groupcompared to control (P=0.03) but the serum squalene did not differ between the groups (P=0.46). Therefore, theserum lathosterol to squalene ratio, a novel index of cholesterol synthesis, was significantly lower in the treatmentgroup compared to control (P=0.03). The EGCG treatment also reduced serum cholesterol by 85{\%} (P=0.02).Conclusions – These in vivo results support the in vitro observation that EGCG is an inhibitor of sqalene epoxidase.",
author = "Roach, {Paul D.} and Nenad NAUMOVSKI and Shipman Kristy and Rick Thorne",
year = "2008",
language = "English",
volume = "17",
pages = "55",
journal = "Asia Pacific Journal of Clinical Nutrition",
issn = "0964-7058",
publisher = "HEC Press",
number = "Suppl 3",

}

Epigallocatechin gallate concomitantly increases the low density lipoprotein receptor and the CD36 protein in the liver of hypercholesterolaemic rabbits. / Roach, Paul D.; NAUMOVSKI, Nenad; Kristy, Shipman; Thorne, Rick.

In: Asia Pacific Journal of Clinical Nutrition, Vol. 17, No. Suppl 3, 2008, p. 55.

Research output: Contribution to journalMeeting Abstract

TY - JOUR

T1 - Epigallocatechin gallate concomitantly increases the low density lipoprotein receptor and the CD36 protein in the liver of hypercholesterolaemic rabbits

AU - Roach, Paul D.

AU - NAUMOVSKI, Nenad

AU - Kristy, Shipman

AU - Thorne, Rick

PY - 2008

Y1 - 2008

N2 - Background – Epigallocatechin gallate (EGCG) is a major green tea catechin which is related to the reduction ofplasma cholesterol in animal models possibly through inhibition of cholesterol synthesis. Consistent with this, invitro studies have shown EGCG to be a non-competitive inhibitor of squalene epoxidase (1). In vivo, inhibition ofsqualene epoxidase could be expected to reduce, relative to squalene, the amount of lathosterol produced; lathosterolis a cholesterol precursor which is produced after squalene in the cholesterol synthetic pathway.Objective – To determine the effect of EGCG on lathosterol relative to squalene in the hypercholesterolaemicrabbit.Design – New Zealand White rabbits (n=12) were fed a rabbit chow with 0.25% (w/w) cholesterol for 2 weeks torender them hypercholesterolaemic. This was followed by a 4-week treatment period during which the control group(n=6) remained on the 0.25% (w/w) cholesterol diet while the treatment group (n=6) was fed the same diet plus 2%(w/w) EGCG added. Serum cholesterol (enzymatic), lathosterol (GC) and squalene (HPLC) were measured.Outcomes – After the 4-week treatment period, serum lathosterol was significantly reduced in the treatment groupcompared to control (P=0.03) but the serum squalene did not differ between the groups (P=0.46). Therefore, theserum lathosterol to squalene ratio, a novel index of cholesterol synthesis, was significantly lower in the treatmentgroup compared to control (P=0.03). The EGCG treatment also reduced serum cholesterol by 85% (P=0.02).Conclusions – These in vivo results support the in vitro observation that EGCG is an inhibitor of sqalene epoxidase.

AB - Background – Epigallocatechin gallate (EGCG) is a major green tea catechin which is related to the reduction ofplasma cholesterol in animal models possibly through inhibition of cholesterol synthesis. Consistent with this, invitro studies have shown EGCG to be a non-competitive inhibitor of squalene epoxidase (1). In vivo, inhibition ofsqualene epoxidase could be expected to reduce, relative to squalene, the amount of lathosterol produced; lathosterolis a cholesterol precursor which is produced after squalene in the cholesterol synthetic pathway.Objective – To determine the effect of EGCG on lathosterol relative to squalene in the hypercholesterolaemicrabbit.Design – New Zealand White rabbits (n=12) were fed a rabbit chow with 0.25% (w/w) cholesterol for 2 weeks torender them hypercholesterolaemic. This was followed by a 4-week treatment period during which the control group(n=6) remained on the 0.25% (w/w) cholesterol diet while the treatment group (n=6) was fed the same diet plus 2%(w/w) EGCG added. Serum cholesterol (enzymatic), lathosterol (GC) and squalene (HPLC) were measured.Outcomes – After the 4-week treatment period, serum lathosterol was significantly reduced in the treatment groupcompared to control (P=0.03) but the serum squalene did not differ between the groups (P=0.46). Therefore, theserum lathosterol to squalene ratio, a novel index of cholesterol synthesis, was significantly lower in the treatmentgroup compared to control (P=0.03). The EGCG treatment also reduced serum cholesterol by 85% (P=0.02).Conclusions – These in vivo results support the in vitro observation that EGCG is an inhibitor of sqalene epoxidase.

M3 - Meeting Abstract

VL - 17

SP - 55

JO - Asia Pacific Journal of Clinical Nutrition

JF - Asia Pacific Journal of Clinical Nutrition

SN - 0964-7058

IS - Suppl 3

ER -