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Page 2 of 7 Strokova et al. Vessel Plus 2019;3:16 I http://dx.doi.org/10.20517/2574-1209.2019.08

disorders detected in childhood and an increased risk of cardiovascular diseases in patients with GSDs. More studies
needed to investigate this issue.

Keywords: Lipid profile, glycogen storage disease, children, triglycerides, LDL cholesterol

INTRODUCTION
Glycogen storage disease (GSD, glycogenosis, dextrinosis) is a common term for a group of hereditary
metabolic disorders associated with impaired glycogen metabolism. The prevalence of GSD varies from one
[1]
case per 20,000 to 300,000 births depending on the type of disease .
The major part of GSDs has an autosomal recessive inheritance (e.g., type IX is X-linked recessive disorder)
and implemented through specific enzyme deficiencies. Furthermore, some cases of simultaneous several
enzymes failure have been described. Defects in synthesis enzymes, as well as glycogen utilization enzymes,
can be observed depending on the GSD type. Genetic disturbances of glycogen metabolism lead to the
accumulation of normal and/or pathologically changed glycogen in internal organs and tissues. The liver,
heart, skeletal muscles and blood cells are affected in GSD I (von Gierke disease), III (Cori or Forbes disease),
[2]
VI (Hers disease), VII (Tarui disease), VIII and IX types . The pronounced metabolic changes cause growth
[2]
and developmental delay at an early age .
[3]
The cardiac pathology in GSDs especially in type II (Pompe disease) is well studied . Among other types,
the most common cardiovascular (CV) disorders are found in children with type III GSD. Myocardial
involvement in GSD is performed by left ventricular hypertrophy, less frequently cardiomegaly, or
isolated right ventricular hypertrophy and, in rare cases, life-threatening arrhythmia and hypertrophic
[4]
cardiomyopathy as non-compact ventricular myocardium . Pulmonary arterial hypertension is another CV
[5,6]
complication of GSD .
The crucial mechanism of CV complications in GSD is dyslipidemia. GSD-associated lipid disorders indicate
[7]
close interactions between the metabolism of carbohydrates and lipids in these patients . In case of such
severe metabolic disorders as GSDs, especially types I and III, affect lipid metabolism in early childhood.

According to the Rake study, hypercholesterolemia and hypertriglyceridemia are more common in type I
[8]
GSD, particularly subtype Ia . Furthermore, pancreatitis and cholelithiasis are prevalent complications of
hyperlipidemia in GSD. Moreover, these patients characterised by the higher relationship of high triglyceride
[9]
levels (> 5.6 mmol/L) with hepatic adenoma development .
Hypertriglyceridemia in GSD type I occurs as a result of a number of reasons. First, a violation of
gluconeogenesis leads to the accumulation of fatty acid precursors, from which triglycerides are subsequently
synthesized. Secondly, a decreased lipoprotein lipase activity causes disturbances in physiological lipolysis
and a decrease in the clearance of triglycerides. In addition, the conditions described above can be
exacerbated by a chronically low level of insulin, which normally inhibits the synthesis of triglyceride-rich
particles in the liver [10,11] . Finally, a fatty liver is a common condition in patients with GSD I as a consequence
[12]
of excess fatty acid transport from the adipose tissue to the liver and increased lipogenesis de novo .
Increased cholesterol synthesis in combination with disturbances of lipoprotein and triglyceride elimination
leads to severe hypercholesterolemia and hypertriglyceridemia in patients with GSD I [13,14] .

In GSD III, hypertriglyceridemia is detected in 67% of patients, while only one-third demonstrates
[15]
hypercholesterolemia. In general, lipid disorders are not as common comparing to GSD I .