Cholesteryl ester storage disease. Report of a case.

Cholesteryl ester storage disease (CESD) is a rare disorder of familial incidence characterized by the accumulation of cholesteryl ester and triglycerides in the liver, intestine and bone marrow. Until now only 21 cases have been reported in the literature. We present a 9 months old girl presenting with increased abdominal girth. She had normal liver function tests and increased cholesterol and triglycerides serum levels. The liver biopsy showed many cholesterol cristals seen as needle shaped cristals under polarized light. This is the youngest patient being diagnosed clinically in the literature.

Will Familial Hypercholesterolaemia Cohorts Hide Many More Lisosomal Acid Lipase Deficiency Patients?

Aims: Lisosomal Acid Lipase Deficiency (LALD), historical known as Cholesterol Ester Storage Disease (CESD), is an autosomal lisosomal storage recessive disorder and an unrecognized cause of dyslipidaemia. Mutations in LIPA gene are the underlying cause of LALD, being a mutation in the splice site of exon 8 the most common cause of the disease. Patients with LALD present dyslipidaemia and altered liver function. The aim of this work was to analyze LIPA gene in patients with unexplained dyslipidaemia.

The upstream enhancer elements of the G6PC promoter are critical for optimal G6PC expression in murine glycogen storage disease type Ia.

Glycogen storage disease type-Ia (GSD-Ia) patients deficient in glucose-6-phosphatase-α (G6Pase-α or G6PC) manifest impaired glucose homeostasis characterized by fasting hypoglycemia, growth retardation, hepatomegaly, nephromegaly, hyperlipidemia, hyperuricemia, and lactic acidemia. Two efficacious recombinant adeno-associated virus pseudotype 2/8 (rAAV8) vectors expressing human G6Pase-α have been independently developed. One is a single-stranded vector containing a 2864-bp of the G6PC promoter/enhancer (rAAV8-GPE) and the other is a double-stranded vector containing a shorter 382-bp minimal G6PC promoter/enhancer (rAAV8-miGPE). To identify the best construct, a direct comparison of the rAAV8-GPE and the rAAV8-miGPE vectors was initiated to determine the best vector to take forward into clinical trials. We show that the rAAV8-GPE vector directed significantly higher levels of hepatic G6Pase-α expression, achieved greater reduction in hepatic glycogen accumulation, and led to a better toleration of fasting in GSD-Ia mice than the rAAV8-miGPE vector. Our results indicated that additional control elements in the rAAV8-GPE vector outweigh the gains from the double-stranded rAAV8-miGPE transduction efficiency, and that the rAAV8-GPE vector is the current choice for clinical translation in human GSD-Ia.

High-density lipoprotein cholesterol, coronary artery disease, and cardiovascular mortality.

AIMS High-density lipoprotein (HDL) cholesterol is a strong predictor of cardiovascular mortality. This work aimed to investigate whether the presence of coronary artery disease (CAD) impacts on its predictive value. METHODS AND RESULTS We studied 3141 participants (2191 males, 950 females) of the LUdwigshafen RIsk and Cardiovascular health (LURIC) study. They had a mean ± standard deviation age of 62.6 ± 10.6 years, body mass index of 27.5 ± 4.1 kg/m², and HDL cholesterol of 38.9 ± 10.8 mg/dL. The cohort consisted of 699 people without CAD, 1515 patients with stable CAD, and 927 patients with unstable CAD. The participants were prospectively followed for cardiovascular mortality over a median (inter-quartile range) period of 9.9 (8.7-10.7) years. A total of 590 participants died from cardiovascular diseases. High-density lipoprotein cholesterol by tertiles was inversely related to cardiovascular mortality in the entire cohort (P = 0.009). There was significant interaction between HDL cholesterol and CAD in predicting the outcome (P = 0.007). In stratified analyses, HDL cholesterol was strongly associated with cardiovascular mortality in people without CAD [3rd vs. 1st tertile: HR (95% CI) = 0.37 (0.18-0.74), P = 0.005], but not in patients with stable [3rd vs. 1st tertile: HR (95% CI) = 0.81 (0.61-1.09), P = 0.159] and unstable [3rd vs. 1st tertile: HR (95% CI) = 0.91 (0.59-1.41), P = 0.675] CAD. These results were replicated by analyses in 3413 participants of the AtheroGene cohort and 5738 participants of the ESTHER cohort, and by a meta-analysis comprising all three cohorts. CONCLUSION The inverse relationship of HDL cholesterol with cardiovascular mortality is weakened in patients with CAD. The usefulness of considering HDL cholesterol for cardiovascular risk stratification seems limited in such patients.

A Missense Change in the ATG4D Gene Links Aberrant Autophagy to a Neurodegenerative Vacuolar Storage Disease.

Inherited neurodegenerative disorders are debilitating diseases that occur across different species. We have performed clinical, pathological and genetic studies to characterize a novel canine neurodegenerative disease present in the Lagotto Romagnolo dog breed. Affected dogs suffer from progressive cerebellar ataxia, sometimes accompanied by episodic nystagmus and behavioral changes. Histological examination revealed unique pathological changes, including profound neuronal cytoplasmic vacuolization in the nervous system, as well as spheroid formation and cytoplasmic aggregation of vacuoles in secretory epithelial tissues and mesenchymal cells. Genetic analyses uncovered a missense change, c.1288G>A; p.A430T, in the autophagy-related ATG4D gene on canine chromosome 20 with a highly significant disease association (p = 3.8 x 10-136) in a cohort of more than 2300 Lagotto Romagnolo dogs. ATG4D encodes a poorly characterized cysteine protease belonging to the macroautophagy pathway. Accordingly, our histological analyses indicated altered autophagic flux in affected tissues. The knockdown of the zebrafish homologue atg4da resulted in a widespread developmental disturbance and neurodegeneration in the central nervous system. Our study describes a previously unknown canine neurological disease with particular pathological features and implicates the ATG4D protein as an important autophagy mediator in neuronal homeostasis. The canine phenotype serves as a model to delineate the disease-causing pathological mechanism(s) and ATG4D function, and can also be used to explore treatment options. Furthermore, our results reveal a novel candidate gene for human neurodegeneration and enable the development of a genetic test for veterinary diagnostic and breeding purposes.

Alternative nighttime nutrition regimens in glycogen storage disease type I: a controlled crossover study

BACKGROUND Traditional approaches for nighttime glycemic control in glycogen storage disease type I (GSDI) include continuous tube feeding, or ingestion of uncooked corn starch (CS) at bedtime. A modified corn starch (MCS) has been shown to prolong euglycemia in some patients. The aim of this study was to evaluate whether stable nighttime glucose control can be achieved with other types of slowly digested carbohydrates in adult GSDI patients. METHODS In this cross-over study, nocturnal glucose control and fasting times were assessed with three different nocturnal nutrition regimens in five patients, using continuous glucose monitoring (CGMS) in an outpatient everyday life setting. For each patient, continuous glucose profiles were measured after ingestion of (1) CS, (2) MCS or (3) a pasta meal at bedtime, during 5 to 6 consecutive nights for each regimen. RESULTS Stable nocturnal glucose control was achieved for all patients with a pasta meal, with a mean duration of glycemia >3.5 mmol/l of 7.6 h (range 5.7-10.8), and >4 mmol/l of 7 h (5.2-9.2), similar to CS and MCS. Fasting glucose before breakfast on workdays (after 7.1 ± 0.8 h) was not significantly different between the three interventions (CS 4.1 ± 0.5 mmol/l, MCS 4.6 ± 0.7 mmol/l, pasta 4.3 ± 0.9 mmol/l). During prolonged fasting on weekends, longer duration of normoglycemia was achieved with CS or MCS than with pasta. CONCLUSION Consumption of cooked pasta is a suitable and more palatable alternative to uncooked corn starch to achieve nighttime glucose control in adult patients with GSDI.

Neonatal gene transfer leads to widespread correction of pathology in a murine model of lysosomal storage disease

For many inborn errors of metabolism, early treatment is critical to prevent long-term developmental sequelae. We have used a gene-therapy approach to demonstrate this concept in a murine model of mucopolysaccharidosis type VII (MPS VII). Newborn MPS VII mice received a single intravenous injection with 5.4 × 106 infectious units of recombinant adeno-associated virus encoding the human β-glucuronidase (GUSB) cDNA. Therapeutic levels of GUSB expression were achieved by 1 week of age in liver, heart, lung, spleen, kidney, brain, and retina. GUSB expression persisted in most organs for the 16-week duration of the study at levels sufficient to either reduce or prevent completely lysosomal storage. Of particular significance, neurons, microglia, and meninges of the central nervous system were virtually cleared of disease. In addition, neonatal treatment of MPS VII mice provided access to the central nervous system via an intravenous route, avoiding a more invasive procedure later in life. These data suggest that gene transfer mediated by adeno-associated virus can achieve therapeutically relevant levels of enzyme very early in life and that the rapid growth and differentiation of tissues does not limit long-term expression.

Estimating the burden of disease attributable to high cholesterol in South Africa in 2000

Objectives To estimate the burden of disease attributable to high cholesterol in adults aged 30 years and older in South Africa in 2000. Design World Health Organization comparative risk assessment (CRA) methodology was followed. Small community studies were used to derive the prevalence by population group. Population-attributable fractions were calculated and applied to revised burden of disease estimates for the relevant disease categories for each population group. The total attributable burden for South Africa in 2000 was obtained by adding the burden attributed to high cholesterol for the four population groups. Monte Carlo simulation-modelling techniques were used for uncertainty analysis. Setting South Africa. Subjects Black African, coloured, white and Indian adults aged 30 years and older. Outcome measures Mortality and disability-adjusted life years (DALYs) from ischaemic heart disease (IHD) and ischaemic stroke. Results Overall, about 59% of IHD and 29% of ischaemic stroke burden in adult males and females (30+ years) were attributable to high cholesterol (≥ 3.8 mmol/l), with marked variation by population group. High cholesterol was estimated to have caused 24 144 deaths (95% uncertainty interval 22 404 - 25 286) or 4.6% (95% uncertainty interval 4.3 - 4.9%) of all deaths in South Africa in 2000. Since most cholesterol-related cardiovascular disease events occurred in middle or old age, the loss of life years comprised a smaller proportion of the total: 222 923 DALYs (95% uncertainty interval 206 712 - 233 460) or 1.4% of all DALYs (95% uncertainty interval 1.3 - 1.4%) in South Africa in 2000. Conclusions High cholesterol is an important cardiovascular risk factor in all population groups in South Africa.

High cholesterol intake modifies chylomicron metabolism in normolipidemic young men

Whether the consumption of egg yolk, which has a very high cholesterol content without excess saturated fats, has deleterious effects on lipid metabolism is controversial. Absorbed dietary cholesterol enters the bloodstream as chylomicrons, but the effects of regular consumption of large amounts of cholesterol on the metabolism of this lipoprotein have not been explored even though the accumulation of chylomicron remnants is associated with coronary artery disease (CAD). We investigated the effects of high dietary cholesterol on chylomicron metabolism in normolipidemic, healthy young men. The plasma kinetics of a chylomicron-like emulsion, doubly-labeled with 14C-cholesteryl ester ( 14C-CE) and 3H-triolein ( 3H-TG) were assessed in 25 men (17-22 y old, BMI 24.1 ± 3.4 kg/m 2). One group (n = 13) consumed 174 ± 41 mg cholesterol/d and no egg yolk. The other group (n = 12) consumed 3 whole eggs/d for a total cholesterol intake of 804 ± 40 mg/d. The nutritional composition of diets was the same for both groups, including total lipids and saturated fat, which comprised 25 and 7%, respectively, of energy intake. Serum LDL and HDL cholesterol and apoprotein B concentrations were higher in the group consuming the high-cholesterol diet (P < 0.05), but serum triacylglycerol, apo AI, and lipoprotein (a) did not differ between the 2 groups. The fractional clearance rate (FCR) of the 14C-CE emulsion, obtained by compartmental analysis, was 52% slower in the high-cholesterol than in the low-cholesterol group (P < 0.001); the 3H-TG FCR did not differ between the groups. Finally, we concluded that high cholesterol intakes increase the residence time of chylomicron remnants, as indicated by the 14C-CE kinetics, which may have undesirable effects related to the development of CAD. © 2006 American Society for Nutrition.

Adjunctive β2-agonist treatment reduces glycogen independently of receptor-mediated acid α-glucosidase uptake in the limb muscles of mice with Pompe disease.

Enzyme or gene replacement therapy with acid α-glucosidase (GAA) has achieved only partial efficacy in Pompe disease. We evaluated the effect of adjunctive clenbuterol treatment on cation-independent mannose-6-phosphate receptor (CI-MPR)-mediated uptake and intracellular trafficking of GAA during muscle-specific GAA expression with an adeno-associated virus (AAV) vector in GAA-knockout (KO) mice. Clenbuterol, which increases expression of CI-MPR in muscle, was administered with the AAV vector. This combination therapy increased latency during rotarod and wirehang testing at 12 wk, in comparison with vector alone. The mean urinary glucose tetrasaccharide (Glc4), a urinary biomarker, was lower in GAA-KO mice following combination therapy, compared with vector alone. Similarly, glycogen content was lower in cardiac and skeletal muscle following 12 wk of combination therapy in heart, quadriceps, diaphragm, and soleus, compared with vector alone. These data suggested that clenbuterol treatment enhanced trafficking of GAA to lysosomes, given that GAA was expressed within myofibers. The integral role of CI-MPR was demonstrated by the lack of effectiveness from clenbuterol in GAA-KO mice that lacked CI-MPR in muscle, where it failed to reverse the high glycogen content of the heart and diaphragm or impaired wirehang performance. However, the glycogen content of skeletal muscle was reduced by the addition of clenbuterol in the absence of CI-MPR, as was lysosomal vacuolation, which correlated with increased AKT signaling. In summary, β2-agonist treatment enhanced CI-MPR-mediated uptake and trafficking of GAA in mice with Pompe disease, and a similarly enhanced benefit might be expected in other lysosomal storage disorders.

Adjunctive albuterol enhances the response to enzyme replacement therapy in late-onset Pompe disease.

Effective dosages for enzyme replacement therapy (ERT) in Pompe disease are much higher than for other lysosomal storage disorders, which has been attributed to low cation-independent mannose-6-phosphate receptor (CI-MPR) in skeletal muscle. We have previously demonstrated the benefit of increased CI-MPR-mediated uptake of recombinant human acid-α-glucosidase during ERT in mice with Pompe disease following addition of albuterol therapy. Currently we have completed a pilot study of albuterol in patients with late-onset Pompe disease already on ERT for >2 yr, who were not improving further. The 6-min walk test (6MWT) distance increased in all 7 subjects at wk 6 (30±13 m; P=0.002), wk 12 (34±14 m; P=0.004), and wk 24 (42±37 m; P=0.02), in comparison with baseline. Grip strength was improved significantly for both hands at wk 12. Furthermore, individual subjects reported benefits; e.g., a female patient could stand up from sitting on the floor much more easily (time for supine to standing position decreased from 30 to 11 s), and a male patient could readily swing his legs out of his van seat (hip abduction increased from 1 to 2+ on manual muscle testing). Finally, analysis of the quadriceps biopsies suggested increased CI-MPR at wk 12 (P=0.08), compared with baseline. With the exception of 1 patient who succumbed to respiratory complications of Pompe disease in the first week, only mild adverse events have been reported, including tremor, transient difficulty falling asleep, and mild urinary retention (requiring early morning voiding). Therefore, this pilot study revealed initial safety and efficacy in an open label study of adjunctive albuterol therapy in patients with late-onset Pompe disease who had been stable on ERT with no improvements noted over the previous several years.

Adjunctive β2-agonists reverse neuromuscular involvement in murine Pompe disease.

Pompe disease has resisted enzyme replacement therapy with acid α-glucosidase (GAA), which has been attributed to inefficient cation-independent mannose-6-phosphate receptor (CI-MPR) mediated uptake. We evaluated β2-agonist drugs, which increased CI-MPR expression in GAA knockout (KO) mice. Clenbuterol along with a low-dose adeno-associated virus vector increased Rotarod latency by 75% at 4 wk, in comparison with vector alone (P<2×10(-5)). Glycogen content was lower in skeletal muscles, including soleus (P<0.01), extensor digitorum longus (EDL; P<0.001), and tibialis anterior (P<0.05) following combination therapy, in comparison with vector alone. Glycogen remained elevated in the muscles following clenbuterol alone, indicating an adjunctive effect with gene therapy. Elderly GAA-KO mice treated with combination therapy demonstrated 2-fold increased wirehang latency, in comparison with vector or clenbuterol alone (P<0.001). The glycogen content of skeletal muscle decreased following combination therapy in elderly mice (P<0.05). Finally, CI-MPR-KO/GAA-KO mice did not respond to combination therapy, indicating that clenbuterol's effect depended on CI-MPR expression. In summary, adjunctive β2-agonist treatment increased CI-MPR expression and enhanced efficacy from gene therapy in Pompe disease, which has implications for other lysosomal storage disorders that involve primarily the brain.