Hepatic microsomal triglyceride transfer protein gene expression in carbohydrate-induced hypertriglyceridemia

Siddika E Karakas, Li Yizhong, Rogelio Almario, Ismail Temel, Thomas Kenny

Research output: Contribution to journalArticle

Abstract

The microsomal triglyceride transfer protein (MTP) facilitates the assembly of very low density lipoproteins (VLDL). To investigate the effects of carbohydrate (CHO)-induced hypertriglyceridemia (HTG) on the hepatic expression of the MTP gene, Golden Syrian hamsters were fed fructose (FR) and sucrose (SUC) enriched diets. Changes in fasting plasma glucose (FPG), insulin, free fatty acids (FFA), TG, VLDL-TG and VLDL-protein were determined. Abundance of hepatic MTP-mRNA was compared to those of albumin (ALB)-mRNA and glyceraldehyde 3-phosphate dehydrogenase (GAPDH)-mRNA. Hepatic secretion rates (SR) of VLDLTG and VLDL-PR were assessed after intravenous Triton WR, 1339 injection. Lipoprotein lipase (LpL) activity of the epididymal fat pads was determined. As compared to the control and SUC, FR increased plasma insulin (FR = 238+24, SUC = 115±17, control = 82±16 μU/ml, p < 0.0001), FFA (FR = 1.93±0.24, SUC = 1.35±0.1, control = 1.47±0.13 mEq/L, p < 0,03) and TG (FR = 215±47, SUC = 93±7, control = 71±16 mg/dl, p < 0.01), without affecting FPG. There was no change in LpL activity. Fructose-feeding increased VLDL-TG-SR (FR = 2.95±0.26, SUC = 1.28±0.34, control = 2.18±0.26 mg/kg.wt/h-1, p < 0.004), but not VLDL- protein-SR. MTP-mRNA abundance did not change when compared to albumin mRNA, however FR-fed hamsters had lower MTP mRNA abundance when compared to GAPDH mRNA (FR = 0.96±0.13, SUC = 1.15±0.14, control = 1.49±0.14 MTP(GAPDH)- mRNA, p < 0.05). The finding that FR-feeding increased VLDL-TG secretion without any increase in MTP mRNA proves that CHO-induced HTG can occur without an increase in hepatic MTP gene expression.

Original languageEnglish (US)
Pages (from-to)267-280
Number of pages14
JournalNutrition Research
Volume19
Issue number2
DOIs
StatePublished - Feb 1999

Fingerprint

Hypertriglyceridemia
Fructose
VLDL Lipoproteins
Carbohydrates
Gene Expression
Sucrose
Liver
Messenger RNA
Glyceraldehyde-3-Phosphate Dehydrogenases
Lipoprotein Lipase
Nonesterified Fatty Acids
Albumins
Fasting
microsomal triglyceride transfer protein
Insulin
Glucose
Mesocricetus
Cricetinae
Adipose Tissue
Proteins

Keywords

  • Hamster
  • Hypertriglyceridemia
  • Insulin-resistance
  • MTP

ASJC Scopus subject areas

  • Endocrinology
  • Endocrinology, Diabetes and Metabolism

Cite this

Hepatic microsomal triglyceride transfer protein gene expression in carbohydrate-induced hypertriglyceridemia. / Karakas, Siddika E; Yizhong, Li; Almario, Rogelio; Temel, Ismail; Kenny, Thomas.

In: Nutrition Research, Vol. 19, No. 2, 02.1999, p. 267-280.

Research output: Contribution to journalArticle

Karakas, Siddika E ; Yizhong, Li ; Almario, Rogelio ; Temel, Ismail ; Kenny, Thomas. / Hepatic microsomal triglyceride transfer protein gene expression in carbohydrate-induced hypertriglyceridemia. In: Nutrition Research. 1999 ; Vol. 19, No. 2. pp. 267-280.
@article{db2ba2ef4476495c9cc4c863ad4e4c5f,
title = "Hepatic microsomal triglyceride transfer protein gene expression in carbohydrate-induced hypertriglyceridemia",
abstract = "The microsomal triglyceride transfer protein (MTP) facilitates the assembly of very low density lipoproteins (VLDL). To investigate the effects of carbohydrate (CHO)-induced hypertriglyceridemia (HTG) on the hepatic expression of the MTP gene, Golden Syrian hamsters were fed fructose (FR) and sucrose (SUC) enriched diets. Changes in fasting plasma glucose (FPG), insulin, free fatty acids (FFA), TG, VLDL-TG and VLDL-protein were determined. Abundance of hepatic MTP-mRNA was compared to those of albumin (ALB)-mRNA and glyceraldehyde 3-phosphate dehydrogenase (GAPDH)-mRNA. Hepatic secretion rates (SR) of VLDLTG and VLDL-PR were assessed after intravenous Triton WR, 1339 injection. Lipoprotein lipase (LpL) activity of the epididymal fat pads was determined. As compared to the control and SUC, FR increased plasma insulin (FR = 238+24, SUC = 115±17, control = 82±16 μU/ml, p < 0.0001), FFA (FR = 1.93±0.24, SUC = 1.35±0.1, control = 1.47±0.13 mEq/L, p < 0,03) and TG (FR = 215±47, SUC = 93±7, control = 71±16 mg/dl, p < 0.01), without affecting FPG. There was no change in LpL activity. Fructose-feeding increased VLDL-TG-SR (FR = 2.95±0.26, SUC = 1.28±0.34, control = 2.18±0.26 mg/kg.wt/h-1, p < 0.004), but not VLDL- protein-SR. MTP-mRNA abundance did not change when compared to albumin mRNA, however FR-fed hamsters had lower MTP mRNA abundance when compared to GAPDH mRNA (FR = 0.96±0.13, SUC = 1.15±0.14, control = 1.49±0.14 MTP(GAPDH)- mRNA, p < 0.05). The finding that FR-feeding increased VLDL-TG secretion without any increase in MTP mRNA proves that CHO-induced HTG can occur without an increase in hepatic MTP gene expression.",
keywords = "Hamster, Hypertriglyceridemia, Insulin-resistance, MTP",
author = "Karakas, {Siddika E} and Li Yizhong and Rogelio Almario and Ismail Temel and Thomas Kenny",
year = "1999",
month = "2",
doi = "10.1016/S0271-5317(98)00190-0",
language = "English (US)",
volume = "19",
pages = "267--280",
journal = "Nutrition Research",
issn = "0271-5317",
publisher = "Elsevier Inc.",
number = "2",

}

TY - JOUR

T1 - Hepatic microsomal triglyceride transfer protein gene expression in carbohydrate-induced hypertriglyceridemia

AU - Karakas, Siddika E

AU - Yizhong, Li

AU - Almario, Rogelio

AU - Temel, Ismail

AU - Kenny, Thomas

PY - 1999/2

Y1 - 1999/2

N2 - The microsomal triglyceride transfer protein (MTP) facilitates the assembly of very low density lipoproteins (VLDL). To investigate the effects of carbohydrate (CHO)-induced hypertriglyceridemia (HTG) on the hepatic expression of the MTP gene, Golden Syrian hamsters were fed fructose (FR) and sucrose (SUC) enriched diets. Changes in fasting plasma glucose (FPG), insulin, free fatty acids (FFA), TG, VLDL-TG and VLDL-protein were determined. Abundance of hepatic MTP-mRNA was compared to those of albumin (ALB)-mRNA and glyceraldehyde 3-phosphate dehydrogenase (GAPDH)-mRNA. Hepatic secretion rates (SR) of VLDLTG and VLDL-PR were assessed after intravenous Triton WR, 1339 injection. Lipoprotein lipase (LpL) activity of the epididymal fat pads was determined. As compared to the control and SUC, FR increased plasma insulin (FR = 238+24, SUC = 115±17, control = 82±16 μU/ml, p < 0.0001), FFA (FR = 1.93±0.24, SUC = 1.35±0.1, control = 1.47±0.13 mEq/L, p < 0,03) and TG (FR = 215±47, SUC = 93±7, control = 71±16 mg/dl, p < 0.01), without affecting FPG. There was no change in LpL activity. Fructose-feeding increased VLDL-TG-SR (FR = 2.95±0.26, SUC = 1.28±0.34, control = 2.18±0.26 mg/kg.wt/h-1, p < 0.004), but not VLDL- protein-SR. MTP-mRNA abundance did not change when compared to albumin mRNA, however FR-fed hamsters had lower MTP mRNA abundance when compared to GAPDH mRNA (FR = 0.96±0.13, SUC = 1.15±0.14, control = 1.49±0.14 MTP(GAPDH)- mRNA, p < 0.05). The finding that FR-feeding increased VLDL-TG secretion without any increase in MTP mRNA proves that CHO-induced HTG can occur without an increase in hepatic MTP gene expression.

AB - The microsomal triglyceride transfer protein (MTP) facilitates the assembly of very low density lipoproteins (VLDL). To investigate the effects of carbohydrate (CHO)-induced hypertriglyceridemia (HTG) on the hepatic expression of the MTP gene, Golden Syrian hamsters were fed fructose (FR) and sucrose (SUC) enriched diets. Changes in fasting plasma glucose (FPG), insulin, free fatty acids (FFA), TG, VLDL-TG and VLDL-protein were determined. Abundance of hepatic MTP-mRNA was compared to those of albumin (ALB)-mRNA and glyceraldehyde 3-phosphate dehydrogenase (GAPDH)-mRNA. Hepatic secretion rates (SR) of VLDLTG and VLDL-PR were assessed after intravenous Triton WR, 1339 injection. Lipoprotein lipase (LpL) activity of the epididymal fat pads was determined. As compared to the control and SUC, FR increased plasma insulin (FR = 238+24, SUC = 115±17, control = 82±16 μU/ml, p < 0.0001), FFA (FR = 1.93±0.24, SUC = 1.35±0.1, control = 1.47±0.13 mEq/L, p < 0,03) and TG (FR = 215±47, SUC = 93±7, control = 71±16 mg/dl, p < 0.01), without affecting FPG. There was no change in LpL activity. Fructose-feeding increased VLDL-TG-SR (FR = 2.95±0.26, SUC = 1.28±0.34, control = 2.18±0.26 mg/kg.wt/h-1, p < 0.004), but not VLDL- protein-SR. MTP-mRNA abundance did not change when compared to albumin mRNA, however FR-fed hamsters had lower MTP mRNA abundance when compared to GAPDH mRNA (FR = 0.96±0.13, SUC = 1.15±0.14, control = 1.49±0.14 MTP(GAPDH)- mRNA, p < 0.05). The finding that FR-feeding increased VLDL-TG secretion without any increase in MTP mRNA proves that CHO-induced HTG can occur without an increase in hepatic MTP gene expression.

KW - Hamster

KW - Hypertriglyceridemia

KW - Insulin-resistance

KW - MTP

UR - http://www.scopus.com/inward/record.url?scp=0033082763&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0033082763&partnerID=8YFLogxK

U2 - 10.1016/S0271-5317(98)00190-0

DO - 10.1016/S0271-5317(98)00190-0

M3 - Article

AN - SCOPUS:0033082763

VL - 19

SP - 267

EP - 280

JO - Nutrition Research

JF - Nutrition Research

SN - 0271-5317

IS - 2

ER -