Ursula da Silveira Matte

CNS involvement in Fabry disease: Clinical and imaging studies before and after 12 months of enzyme replacement therapy

Summary: We report the clinical and radiological central nervous system (CNS) findings of 8 Fabry disease patients, before (8/8) and after (7/8) 12 months of enzyme replacement therapy (ERT) with agalsidase-alpha. Eight biochemically proven Fabry disease patients (from four families) were included. Patients were evaluated at baseline and at regular intervals during 12 months of ERT. Evaluations included a thorough, standardized neurological examination, and magnetic resonance imaging (MRI) and angiography (MRA). Brain proton magnetic resonance spectroscopy (MRS) was also performed in 5/8 patients. The presence and location of grey- and white-matter lesions, the presence of vascular occlusion or ectasia on MRA and the metabolite ratios on MRS were determined, as well as their relation to age, symptoms and neurological examination. Neurological examination showed few abnormalities in these patients: scores varied (on a 0–100 scale) from zero to 5, at baseline and in the 12th month of ERT. The most consistent findings on MRI were asymmetric, widespread patterns of deep white-matter (WM) lesions, hyperintense on T2 and FLAIR-weighted images, found in 4/8 patients at baseline, predominantly in frontal and parietal lobes. These lesions did not correlate with other clinical variables, although there was a trend towards an association of the lesions with age and hearing loss. The youngest patient with MRI lesions was 24 years old. After 12 months of ERT, MRI was normal in 3/7, showed the same WM lesions in 2/7, and showed worsening of WM lesions in 2/7 patients (from the same family). Abnormal MRS metabolite ratios were detected at baseline in 4/5 patients. While neurological examination remained almost normal during the 12 months of ERT, new small-vessel CNS involvement still appeared in 2/7 patients. We do not know why ERT was not able to prevent this in these two related male patients. This could be due either to their older ages (46 and 36 years), or to a more pathogenic mutation. We conclude that MRI was more sensitive than neurological examination in detecting CNS involvement and progression in Fabry disease in the time interval studied.

Guidelines for the Management of Mucopolysaccharidosis Type I

Mucopolysaccharidosis type I (MPS I) is the prototype of the MPS disorders, a subgroup of lysosomal storage diseases. The incidence of MPS I in Brazil is unknown, but a retrospective population study in Australia conducted between 1980 and 1996 yielded an overall prevalence of 1 in 22 500 for all MPS types. 1 In British Columbia, cases ascertained between 1952 and 1986 determined that the frequency of MPS type I Hurler, the most severe form of the disease, was approximately 1 in 144 000 newborns, 2 a result similar to that found in The Netherlands. 3 A recent analysis of data collected by the Society for Mucopolysaccharides in the United Kingdom in patients with MPS I found a prevalence of 1.07 per 100 000 births. 4 MPS I is characterized by a deficiency in a-L-iduronidase enzyme activity, leading to buildup and urinary excretion of high levels of glycosaminoglycans (GAGs), specifically dermatan and heparan sulfates. The disease is genetically determined and shows autosomal recessive inheritance. 5,6 MPS

Correlation between lactose absorption and the C/T-13910 and G/A-22018 mutations of the lactase-phlorizin hydrolase (LCT) gene in adult-type hypolactasia

The C/T-13910 mutation is the major factor responsible for the persistence of the lactase-phlorizin hydrolase (LCT) gene expression. Mutation G/A-22018 appears to be only in co-segregation with C/T-13910. The objective of the present study was to assess the presence of these two mutations in Brazilian individuals with and without lactose malabsorption diagnosed by the hydrogen breath test (HBT). Ten milk-tolerant and 10 milk-intolerant individuals underwent the HBT after oral ingestion of 50 g lactose (equivalent to 1 L of milk). Analyses for C/T-13910 and G/A-22018 mutations were performed using a PCR-based method. Primers were designed for this study based on the GenBank sequence. The CT/GA, CT/AA, and TT/AA genotypes (lactase persistence) were found in 10 individuals with negative HBT. The CC/GG genotype (lactase non-persistence) was found in 10 individuals, 9 of them with positive HBT results. There was a significant agreement between the presence of mutations in the LCT gene promoter and HBT results (kappa = -0.9, P < 0.001). The CT/AA genotype has not been described previously and seems to be related to lactase persistence. The present study showed a significant agreement between the occurrence of mutations G/A-22018 and C/T-13910 and lactose absorption in Brazilian subjects, suggesting that the molecular test used here could be proposed for the laboratory diagnosis of adult-type primary hypolactasia.

Birth mode-dependent association between pre-pregnancy maternal weight status and the neonatal intestinal microbiome.

The intestinal microbiome is a unique ecosystem that influences metabolism in humans. Experimental evidence indicates that intestinal microbiota can transfer an obese phenotype from humans to mice. Since mothers transmit intestinal microbiota to their offspring during labor, we hypothesized that among vaginal deliveries, maternal body mass index is associated with neonatal gut microbiota composition. We report the association of maternal pre-pregnancy body mass index on stool microbiota from 74 neonates, 18 born vaginally (5 to overweight or obese mothers) and 56 by elective C-section (26 to overweight or obese mothers). Compared to neonates delivered vaginally to normal weight mothers, neonates born to overweight or obese mothers had a distinct gut microbiota community structure (weighted UniFrac distance PERMANOVA, p < 0.001), enriched in Bacteroides and depleted in Enterococcus, Acinetobacter, Pseudomonas, and Hydrogenophilus. We show that these microbial signatures are predicted to result in functional differences in metabolic signaling and energy regulation. In contrast, among elective Cesarean deliveries, maternal body mass index was not associated with neonatal gut microbiota community structure (weighted UniFrac distance PERMANOVA, p = 0.628). Our findings indicate that excess maternal pre-pregnancy weight is associated with differences in neonatal acquisition of microbiota during vaginal delivery, but not Cesarean delivery. These differences may translate to altered maintenance of metabolic health in the offspring.

Bone marrow derived cells decrease inflammation but not oxidative stress in an experimental model of acute myocardial infarction

AIMS Bone marrow cell (BMC) therapy is thought to exert beneficial effects on the infarcted heart. We assessed cardiac function and its correlation with redox status and inflammation in cardiac tissue early post-AMI in rats treated with BMC. MAIN METHODS Male Wistar rats (8-week-old) were randomized into four groups: Sham-operated (S); AMI; S+treatment (ST) and AMI+treatment (AMIT). Therapy with BMC was carried out immediately post-experimental left anterior coronary artery ligation induced-AMI, and assessments made 48h later. Cardiac function and morphometrics were evaluated by echocardiographyc parameters in vivo. Cardiac tissue tumor necrosis factor (TNF)-α and interleukin (IL)-6 were measured by Western Blot. Oxidative stress parameters including reduced (GSH) and oxidized (GSSG) glutathione ratio, hydrogen peroxide level, lipid and protein oxidation, superoxide dismutase, catalase and glutathione peroxidase activities were measured spectrophotometrically. KEY FINDINGS Ejection fraction was lower in infarcted groups and did not improve in BMC-treated animals: AMI (51±5%) vs. S (74±7%) and AMIT (56±10%) vs. ST groups (73±3%). Both TNF-α and IL-6 myocardial expression increased post-AMI and were reduced following BMC therapy. Nonetheless, there was a decrease in GSH/GSSG ratio in infarcted groups which was greater in BMC-treated groups: AMI (8.21±3.8) vs. S (14.61±3.4) and AMIT (2.1±0.7) vs. ST (4.7±1.5). SIGNIFICANCE The data suggest that BMC promoted a redox status favorable to the oxidation of the pro-inflammatory cytokines in the myocardium, exerting an anti-inflammatory-like effect.

White matter lesions in Fabry disease before and after enzyme replacement therapy: a 2-year follow-up

PURPOSE To report the clinical and neuroimaging, central nervous system (CNS) findings of patients with Fabry disease (FD) during 24 months of enzyme replacement therapy (ERT) with agalsidase-alpha. METHOD Eight patients were included. Six completed 24 months of ERT. Clinical and magnetic resonance imaging (MRI) data were obtained at 0, 12 and 24 months of ERT. White matter lesions (WML) were evaluated as well as their relation to age, symptoms and neurological examination (CNS score). RESULTS MRI was stable in 3 patients. WML and CNS score worsened in one patient, fluctuated in another, and improved in the sixth patient. In the whole series, there were 15 WML at baseline, and 19 at the 24th month. In two years, 4 lesions disappeared, whereas 8 appeared. CONCLUSION A widespread pattern of silent WML in FD was seen. In two years, some WML appeared, and some disappeared. If these phenomena were related to the natural history, remains to be demonstrated.

An analysis of the global expression of microRNAs in an experimental model of physiological left ventricular hypertrophy.

Background MicroRNAs (miRs) are a class of small non-coding RNAs that regulate gene expression. Studies of transgenic mouse models have indicated that deregulation of a single miR can induce pathological cardiac hypertrophy and cardiac failure. The roles of miRs in the genesis of physiological left ventricular hypertrophy (LVH), however, are not well understood. Objective To evaluate the global miR expression in an experimental model of exercise-induced LVH. Methods Male Balb/c mice were divided into sedentary (SED) and exercise (EXE) groups. Voluntary exercise was performed on an odometer-monitored metal wheels for 35 days. Various tests were performed after 7 and 35 days of training, including a transthoracic echocardiography, a maximal exercise test, a miR microarray (miRBase v.16) and qRT-PCR analysis. Results The ratio between the left ventricular weight and body weight was increased by 7% in the EXE group at day 7 (p<0.01) and by 11% at day 35 of training (p<0.001). After 7 days of training, the microarray identified 35 miRs that were differentially expressed between the two groups: 20 were up-regulated and 15 were down-regulated in the EXE group compared with the SED group (p = 0.01). At day 35 of training, 25 miRs were differentially expressed: 15 were up-regulated and 10 were decreased in the EXE animals compared with the SED animals (p<0.01). The qRT-PCR analysis demonstrated an increase in miR-150 levels after 35 days and a decrease in miR-26b, miR-27a and miR-143 after 7 days of voluntary exercise. Conclusions We have identified new miRs that can modulate physiological cardiac hypertrophy, particularly miR-26b, -150, -27a and -143. Our data also indicate that previously established regulatory gene pathways involved in pathological LVH are not changed in physiological LVH.

Transcoronary gradient of plasma microRNA 423-5p in heart failure: evidence of altered myocardial expression

Abstract Context: Elevated plasmatic microRNAs (miRs) are observed in heart failure (HF). However, the cardiac origin of these miRs remains unclear. Objective: We calculated transcoronary gradients of miR-29b, miR-133a and miR-423-5p in 17 outpatients with stable systolic HF and in controls without structural cardiac disease. Materials and methods: MicroRNAs were measured by quantitative real-time polymerase chain reaction. Results: Positive transcoronary miR gradients were observed in patients with HF but not in controls (p = 0.03). B-type natriuretic peptide (BNP) moderately correlated with the transcoronary gradients of miR-133a and miR-423-5p. Discussion and conclusions: The difference in transcoronary gradients between HF outpatients and controls suggests that miR-423-5p has a cardiac origin. The positive correlation between miR-423-5p and BNP transcoronary gradients supports this hypothesis.

Fabry Disease in Hemodialysis Patients in Southern Brazil: Prevalence Study and Clinical Report

Background. Fabry disease (FD) is a lysosomal storage disorder caused by a deficiency of α-Galactosidase A (α-Gal A). Fabry nephropathy typically progresses throughout the fifth decade to end-stage renal disease (ESRD), requiring hemodialysis and/or kidney transplantation. Objective. To estimate the prevalence of FD among ESRD males on hemodialysis treatment in Rio Grande do Sul, the southernmost state of Brazil. Methods. Screening for α-Gal A activity was performed by a dried blood spot (normal reference value: >1.5 nmoles/hour/mL). Positive screening results were confirmed by plasma α-Gal A activity assay (reference value: >3.3 nmoles/hour/mL). Results. Five hundred fifty-eight male patients on hemodialysis were evaluated. Of these, only two had low α-Gal A activity and were diagnosed with Fabry disease (0.36%). One of these, age 42, had left ventricular hypertrophy and renal manifestations of Fabry disease without the classic symptoms. The other, age 46, had the classical manifestations of angiokeratomas, acroparesthesias, hypohidrosis, and ocular opacities. Conclusions. Although the prevalence of Fabry disease was very low in our study (0.36%), routine screening of male hemodialysis patients would enable earlier identification of many other affected relatives in their families who might benefit from specific clinical treatment.

Mutations, Clinical Findings and Survival Estimates in South American Patients with X-Linked Adrenoleukodystrophy

In this study, we analyzed the ABCD1 gene in X-linked adrenoleukodystrophy (X-ALD) patients and relatives from 38 unrelated families from South America, as well as phenotypic proportions, survival estimates, and the potential effect of geographical origin in clinical characteristics. Methods X- ALD patients from Brazil, Argentina and Uruguay were invited to participate in molecular studies to determine their genetic status, characterize the mutations and improve the genetic counseling of their families. All samples were screened by SSCP analysis of PCR fragments, followed by automated DNA sequencing to establish the specific mutation in each family. Age at onset and at death, male phenotypes, genetic status of women, and the effect of family and of latitude of origin were also studied. Results We identified thirty-six different mutations (twelve novel). This population had an important allelic heterogeneity, as only p.Arg518Gln was repeatedly found (three families). Four cases carried de novo mutations. Intra-familiar phenotype variability was observed in all families. Out of 87 affected males identified, 65% had the cerebral phenotype (CALD). The mean (95% CI) ages at onset and at death of the CALD were 10.9 (9.1–12.7) and 24.7 (19.8–29.6) years. No association was found between phenotypic manifestations and latitude of origin. One index-case was a girl with CALD who carried an ABCD1 mutation, and had completely skewed X inactivation. Conclusions This study extends the spectrum of mutations in X-ALD, confirms the high rates of de novo mutations and the absence of common mutations, and suggests a possible high frequency of cerebral forms in our population.