Late-onset fabry disease due to the p.Phe113Leu variant: the first italian cluster of five families.

BACKGROUND: The GLA c.337T > C (p.Phe113Leu) is a known pathogenic variant associated to late-onset Fabry disease phenotype with predominant cardiac manifestations. A founder effect was demonstrated in a large cohort in the Portuguese region of Guimarães. Herein we report an in-depth phenotype description of a cluster of five Southern Italy families. METHODS: Family pedigrees of five index males with the p.Phe113Leu variant were obtained and all at-risk relatives underwent biochemical and genetical screening test. Carriers of GLA p.Phe113Leu variant underwent subsequent multidisciplinary clinical and instrumental evaluation. RESULTS: Thirty-one (16 M, 15 F) individuals with p.Phe113Leu pathogenic variant were identified. Sixteen out of 31 patients (51.6%) had cardiac manifestations. Notably, myocardial fibrosis was found in 7/8 patients, of whom 2 were under 40 years. Stroke occurred in 4 patients. White matter lesions were detected in 12/19 patients and occurred in 2/10 of subjects under 40 years. Seven females complained of acroparesthesias. Renal involvement occurred in 10 patients. Angiokeratomas were evident in 9 subjects. Eyes, ear, gastrointestinal and pulmonary involvement occurred in the minority of subjects. CONCLUSION: This study demonstrates that a cluster of subjects with p.Phe113Leu pathogenic variant is also present in Southern Italy. Disease manifestations are frequent in both sexes and may occur early in life. Cardiac involvement represents the core manifestation, but neurological and renal involvement is also frequent, suggesting that extra-cardiac complications deserve clinical attention.

Identification of Hypothalamic Long Noncoding RNAs Associated with Hypertension and the Behavior/Neurological Phenotype of Hypertensive ISIAH Rats.

Long noncoding RNAs (lncRNAs) play an important role in the control of many physiological and pathophysiological processes, including the development of hypertension and other cardiovascular diseases. Nonetheless, the understanding of the regulatory function of many lncRNAs is still incomplete. This work is a continuation of our earlier study on the sequencing of hypothalamic transcriptomes of hypertensive ISIAH rats and control normotensive WAG rats. It aims to identify lncRNAs that may be involved in the formation of the hypertensive state and the associated behavioral features of ISIAH rats. Interstrain differences in the expression of seven lncRNAs were validated by quantitative PCR. Differential hypothalamic expression of lncRNAs LOC100910237 and RGD1562890 between hypertensive and normotensive rats was shown for the first time. Expression of four lncRNAs (Snhg4, LOC100910237, RGD1562890, and Tnxa-ps1) correlated with transcription levels of many hypothalamic genes differentially expressed between ISIAH and WAG rats (DEGs), including genes associated with the behavior/neurological phenotype and hypertension. After functional annotation of these DEGs, it was concluded that lncRNAs Snhg4, LOC100910237, RGD1562890, and Tnxa-ps1 may be involved in the hypothalamic processes related to immune-system functioning and in the response to various exogenous and endogenous factors, including hormonal stimuli. Based on the functional enrichment analysis of the networks, an association of lncRNAs LOC100910237 and Tnxa-ps1 with retinol metabolism and an association of lncRNAs RGD1562890 and Tnxa-ps1 with type 1 diabetes mellitus are proposed for the first time. Based on a discussion, it is hypothesized that previously functionally uncharacterized lncRNA LOC100910237 is implicated in the regulation of hypothalamic processes associated with dopaminergic synaptic signaling, which may contribute to the formation of the behavioral/neurological phenotype and hypertensive state of ISIAH rats.

Plppr5 gene inactivation causes a more severe neurological phenotype and abnormal mitochondrial homeostasis in a mouse model of juvenile seizure.

Mice with inactivation of the Plppr5 gene (Plppr5-/-) had aggravated hypoxic-ischemic damage and partially weakened neuroprotection of melatonin (a mitochondrial targeted antioxidant), suggesting that abnormal mitochondrial homeostasis contributes to neurological abnormalities in these mice. We examined the hypothesis that Plppr5 inactivation disturbs mitochondrial homeostasis, which may cause long-term adverse consequences on behavior and cognition. We studied the long-term effects of Plppr5 knockout (KO) in both wild-type (WT) and Plppr5-null mice using a combination of neurobehavior, cognition, and standard cellular glutamate-induced excitotoxicity techniques. The change in mitochondrial membrane potential was determined by detecting MitoTracker Green FM and MitoTracker Red CMXROS with a Gallios flow cytometer. Our results suggest that Plppr5 gene knockout aggravated the impairment of exploratory behavior (open field test) and memory (novel object recognition and passive avoidance tests) in Plppr5-null mice following juvenile seizures. Furthermore, Plppr5 gene silencing aggravated the decrease in the cell survival rate of HT22 cells treated with glutamate for 24 h and further resulted in a decrease in superoxide dismutase (SOD) levels and the ratio of active mitochondria and a parallel increase in the reactive oxygen species (ROS) content. Interestingly, silencing the Plppr5 gene alone in vitro is sufficient to reduce the cell survival rate, aggravate oxidative stress damage, reduce the proportion of surviving mitochondria, and upregulate mitophagy activity. In summary, the present data reveal the first direct link between Plppr5 KO and neurobehavioral and cognitive impairment following juvenile seizures and provide a potential mechanistic explanation for the adverse consequences. Given that silencing the Plppr5 gene is sufficient to upregulate mitophagy activity and aggravate oxidative stress neuronal damage, our results suggest that Plppr5 substrates and/or mitophagy-based treatments may provide valuable new targets for the treatment of developmental convulsive brain injury.

Cognitive impairment in stable Wilson disease across phenotype.

In Wilson disease (WD), mutations in the gene encoding the ATP7B copper transport protein causes accumulation of copper especially in liver and brain. WD typically presents with hepatic and/or neuropsychiatric symptoms. Impaired cognition is a well-described feature in patients with neurological WD, while the reports on cognition in hepatic WD patients are fewer and less conclusive. We examined cognition in a cohort of WD patients with both phenotypes. In this cross-sectional pilot study, we investigated cognition in 28 stable Danish WD patients by the PortoSystemic Encephalopathy (PSE) and the Continuous Reaction Time (CRT) tests. Half of the patients were female, and their median age was 35.5 years (IQR 24.5). Their phenotype was hepatic in 14 (50%), neurologic in 10 (36%) and mixed in 4 (14%). The duration of treatment was > 2 year in all patients, and their condition was stable as judged by urinary copper excretion, liver enzymes, and clinical assessment. The hepatic patients did not show signs of liver failure. In total, 16 (57%) patients performed worse than normal in the PSE and/or the CRT tests. The two tests were correlated (rho = 0.60, p = 0.0007), but neither correlated with phenotype, MELD-, Child-Pugh score, 24 h-U-Cu, or treatment type. Measurable cognitive impairment was present in more than half of the stable WD patients independent of phenotype. Thus, our data questions the existence of a purely hepatic phenotype.

The absence of the aryl hydrocarbon receptor in the R6/1 transgenic mouse model of Huntington's disease improves the neurological phenotype.

Huntington's disease (HD) is an inherited neurodegenerative disorder caused by an abnormal CAG repeat expansion in the huntingtin gene coding for a protein with an elongated polyglutamine sequence. HD patients present choreiform movements, which are caused by the loss of neurons in the striatum and cerebral cortex. Previous reports indicate that the absence of the aryl hydrocarbon receptor (AhR) protects mice from excitotoxic insults and increases the transcription of neurotrophic factors. Based on these data, we evaluated the effects of the lack of the AhR on a mice model of HD, generating a double transgenic mouse, expressing human mutated huntingtin (R6/1 mice) and knockout for the AhR. Our results show that the body weight of 30-week-old double transgenic mice is similar to that of R6/1 mice; however, feet clasping, an indicative of neuronal damage in the R6/1 animals, was not observed. In addition, motor coordination and ambulatory behavior in double transgenic mice did not deteriorate over time as occur in the R6/1 mice. Moreover, the anxiety behavior of double transgenic mice was similar to wild type mice. Interestingly, astrogliosis is also reduced in the double transgenic mice. The present data demonstrate that the complete loss of the AhR reduces the motor and behavioral deterioration observed in R6/1 mice, suggesting that the pharmacological modulation of the AhR could be a therapeutic target in HD.