👤 Maria Eugenia Soto Martín

Resveratrol (Rsv) is a natural polyphenol with neuroprotective properties that modulates several pathways implicated in Alzheimer's disease (AD). Cholesterol homeostasis is disrupted in AD patients, and this imbalance plays a key role in amyloid precursor protein (APP) processing, β-amyloid aggregation and membrane stability. The effect of Rsv on the cerebellum, an emerging structure in cognitive networks and AD pathology due to its high connectivity with other brain regions, remains largely unexplored. This study aims to characterize the effects of Rsv on the cerebellum of SAMP8 mice, an animal model of AD, at different ages (5- and 7-month-old mice) and to investigate how it act as a neuroprotective polyphenol in this structure via modulation of cholesterol metabolism. Aging caused a significant increase in cerebellar membrane free cholesterol levels, which were reversed by Rsv treatment. HMG-CoA reductase levels were significantly reduced by Rsv treatment in 5-month-old mice, suggesting that this polyphenol modulates cholesterol synthesis. Parameters related to cholesterol trafficking were also modulated, with increased LDL receptor levels, but without affecting ApoE. Mitochondrial electron transport chain complexes were also upregulated by Rsv treatment in 5-month-old animals, without affecting mitochondrial dynamics. Collectively, these data demonstrate-for the first time-that Rsv modulates key aspects of cholesterol metabolism and mitochondrial function in the cerebella of SAMP8 mice. Show less

Lecanemab, an antibody directed at Aβ-protofibrils and plaque, showed meaningful delay in disease progression and biological effects consistent with disease modification in the phase 3 Clarity AD trial. The objective of this paper is to present efficacy and safety results in ApoE ε4 non-carriers or heterozygotes population of Clarity AD. Clarity AD is an 18-month, randomized study (core) in participants with early AD, with an open-label extension phase (OLE) phase. Academic and clinical centers. All eligible ApoE ε4 participants were randomized 1:1 across 2 treatment groups (placebo and lecanemab 10 mg/kg biweekly); the results presented herein are for the ApoE4 heterozygote or non-carrier participants. Endpoints included change from baseline at 18 months in the global cognitive and functional scale, CDR-SB, amyloid positron emission tomography (PET), Alzheimer's Disease Assessment Scale-Cognitive Subscale 14 (ADAS-Cog14), Alzheimer's Disease Cooperative Study-Activities of Daily Living Scale for Mild Cognitive Impairment (ADCS-MCI-ADL), and health-related quality-of-life (HRQoL) assessments. Amyloid imaging related abnormalities (ARIA) occurrence was monitored throughout the study by central reading of magnetic resonance imaging. Following 18 months treatment in the Core, eligible participants transitioned to the OLE where they received open-label lecanemab. Clinical outcomes (CDR-SB, ADAS-Cog14, and ADCS-MCI-ADL) were evaluated by examining 'delayed start' (core:placebo followed by OLE:lecanemab) and 'early start' (core:lecanemab followed by OLE:lecanemab) cohorts as well as natural history cohorts. Time to progression to next stage of AD was also evaluated through 36 months. 1795 participants with early AD were enrolled in Clarity AD, of which 1521 were ApoE ε4 heterozygotes or non-carriers (85 %). Lecanemab significantly reduced clinical decline on CDR-SB at 18 months compared to placebo in the ApoEε4 heterozygotes or non-carriers subgroup. Amyloid PET, ADAS-Cog14, ADCS-MCI-ADL, and HRQoL results were consistent with the CDR-SB findings. In the analysis subgroup, the most common adverse reactions for lecanemab were infusion-related reactions (26 %), ARIA-H (13 %), fall (11 %), headache (11 %), and ARIA-E (9 %). In the OLE, lecanemab-treated participants continued to accrue benefit in CDR-SB through 36 months, with continued separation through 36 months relative to the ADNI natural history cohort. Delayed start results follow a parallel trajectory relative to early start results, but do not catch up, confirming a disease modifying effect and reflecting importance of early treatment initiation. Results were similar for ADAS-Cog14 and ADCS-MCI-ADL. Lecanemab reduced the risk of progression to next stage of AD by 28 % on lecanemab as compared to the ADNI natural history cohort. In the ApoE ε4 heterozygotes or non-carrier subgroup of Clarity AD, lecanemab slowed decline in disease progression and reduced markers of amyloid, with expanding benefit over time. Clarity AD NCT03887455. Show less

The Saccharomyces cerevisiae Cell Wall Integrity (CWI) pathway responds to cell wall stress and is composed of MAP3K Bck1, MAP2Ks Mkk1 and Mkk2 and MAPK Slt2. Although human ERK5 has been considered the functional orthologue of Slt2, our results indicate that human ERK1 and ERK2 exhibit a much greater ability than ERK5 to replace Slt2 under various cell wall stresses. ERK5 is only able to slightly complement an slt2Δ mutant phenotype in the presence of tunicamycin, and the constitutively active truncated version ERK5ΔCt did not improve this complementation ability. Like Slt2, ERK1, ERK2 and ERK5ΔCt are concentrated in the nucleus, and show higher phosphorylation than ERK5 upon CWI pathway stimulation. Expression of a hyperactive version of the human MAP2K MEK5 leads to specific ERK5 and ERK5ΔCt phosphorylation, leading to a partial replacement of the Mkk1/2-Slt2 function under cell wall stress. Expressed in yeast, the human Dual Specificity Phosphatases DUSP3 and DUSP6 reduce the level of ERK5 phosphorylation to a similar extent, whereas DUSP6 shows higher activity than DUSP3 on ERK1 or ERK2. Our results show the different degree of integration of human ERKs and DUSPs into the yeast CWI signalling circuit, which can be exploited for functional analysis or pharmacological screenings. Show less

Congenital myasthenic syndromes (CMSs) and primary mitochondrial myopathies (PMMs) can present with ptosis, external ophthalmoplegia, and limb weakness. Our method involved the description of three cases of CMS that were initially characterized as probable PMM. All patients were male and presented with ptosis and/or external ophthalmoplegia at birth, with proximal muscle weakness and fatigue on physical exertion. After normal repetitive nerve stimulation (RNS) studies performed on facial muscles, a muscle biopsy (at a median age of 9) was performed to rule out congenital myopathies. In all three cases, the biopsy findings (COX-negative fibers or respiratory chain defects) pointed to PMM. They were referred to our neuromuscular unit in adulthood to establish a genetic diagnosis. However, at this time, fatigability was evident in the physical exams and RNS in the spinal accessory nerve showed a decremental response in all cases. Targeted genetic studies revealed pathogenic variants in the Early identification of CMS is essential as medical treatment can provide clear benefits. Its diagnosis can be challenging due to phenotypic overlap with other debilitating disorders. Thus, a high index of suspicion is necessary to guide the diagnostic strategy. Show less

Cholesterol metabolism seems dysregulated and linked to amyloid-β (Aβ) formation in neurodegeneration, but the underlying mechanisms are poorly known. Resveratrol (RSV) is a polyphenol with antioxidant activity and neuroprotective properties. Here, we analyzed the effect of age and RSV supplementation on cholesterol metabolism in the brain and blood serum, and its potential link to Aβ processing, in SAMP8 mice-an animal model of aging and Alzheimer's disease. In the brain, our results revealed an age-related increase in ApoE and unesterified cholesterol in the plasma membrane whereas LDL receptor, HMG-CoA reductase, HMG-CoA-C1 synthase, and ABCA1 transporter remained unaltered. Furthermore, BACE-1 and APP gene expression was decreased. This dysregulation could be involved in the amyloidogenic processing pathway of APP towards Aβ formation. In turn, RSV exhibited an age-dependent effect. While levels of unesterified cholesterol in the plasma membrane were not affected by RSV, several participants in cholesterol uptake, release, and de novo synthesis differed, depending on age. Thus, RSV supplementation exhibited a different neuroprotective effect acting on Aβ processing or cholesterol metabolism in the brain at earlier or later ages, respectively. In blood serum, HDL lipoprotein and free cholesterol were increased by age, whereas VLDL and LDL lipoproteins remained unaltered. Again, the protective effect of RSV by decreasing the LDL or increasing the HDL levels also seems to depend on the intervention's moment. In conclusion, age is a prominent factor for cholesterol metabolism dysregulation in the brain of SAMP8 mice and influences the protective effects of RSV through cholesterol metabolism and Aβ processing. Show less

The main aim was to evaluate changes in urea cycle enzymes in NAFLD patients and in two preclinical animal models mimicking this entity. Seventeen liver specimens from NAFLD patients were included for immunohistochemistry and gene expression analyses. Three-hundred-and-eighty-two biopsy-proven NAFLD patients were genotyped for rs1047891, a functional variant located in carbamoyl phosphate synthetase-1 (CPS1) gene. Two preclinical models were employed to analyse CPS1 by immunohistochemistry, a choline deficient high-fat diet model (CDA-HFD) and a high fat diet LDLr knockout model (LDLr -/-). A significant downregulation in mRNA was observed in CPS1 and ornithine transcarbamylase (OTC1) in simple steatosis and NASH-fibrosis patients versus controls. Further, age, obesity (BMI > 30 kg/m Show less

Superficial fungal infections are common in dermatology and are often caused by opportunistic species in the Candida and Malassezia genera. The aim of this study was to analyze changes in the expression of genes coding for enzymes involved in the biosynthesis of glycosaminoglycans (GAGs) chains following the adherence of Candida and Malassezia yeasts to skin cell lines. Gene expression was analyzed using reverse transcriptase-quantitative polymerase chain reaction assays. Interactions between the yeasts and the skin cells induced the following changes in genes involved in the biosynthesis of heparan sulfate and chondroitin sulfate: downregulation of CHPF in keratinocytes and downregulation of EXT1, EXT2, CHSY3, and CHPF in fibroblasts. Adherence to fibroblasts had an even greater effect on GAG biosynthetic enzymes, inducing the downregulation of 13 genes and the upregulation of two (CHST15 and CHST7). Interactions between yeasts and skin cells might affect the binding affinity of GAG chains, possibly changing their ability to function as receptors for pathogens and interfering with a key stage at the start of infection. Show less

To explore the association between Triglyceride/High-density lipoprotein cholesterol (TG/HDL-C) index and these enzymes and proteins in a pediatric population. Children and adolescents (7-14 y old) were recruited (n = 150) and anthropometric data were registered. Glucose, TG, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), HDL-C plus cholesteryl ester transfer protein (CETP), lipoprotein-associated phospholipase A Twenty-five individuals presented TG/HDL-C ratio ≥ 3.0. These individuals exhibited higher TG [164 (126-186) vs. 65 (48-72) mg/dL; p < 0.01] CETP [250 (232-263) vs. 223 (193-237)% mL/min; p < 0.01] and Lp-PLA Children and adolescents with TG/HDL-C ≥ 3.0 presented a more atherogenic lipid profile and higher CETP and Lp-PLA Show less

Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiac disease. The current challenge relies on the accurate classification of the pathogenicity of the variants. Transthoracic echocardiography (TTE) is recommended at initial evaluation and cardiac magnetic resonance (CMR) imaging should also be considered. We aimed to reappraise the penetrance and clinical expression of the MYBPC3 p.G263* variant. Three hundred and eighty-four HCM probands and a control cohort of 450 individuals were studied for the main sarcomere genes by next-generation sequencing. All MYBPC3 p.G263* carriers were identified and family screening was performed. Clinical information was recorded retrospectively before 2015 and prospectively thereafter. Extra effort was invested in performing CMR in all carriers, despite TTE results. Thirteen HCM probands and none of the controls were carriers of the MYBPC3 p.G263* pathogenic variant (according to the American College of Medical Genetics and Genomics and the Association for Molecular Pathology). A total of 39 carriers were identified with family screening. Most patients with HCM were asymptomatic at the time of diagnosis and showed late-onset disease. Despite having a relatively benign course in the young, late HCM-related complications could occur. Penetrance was around 70% when evaluated by TTE and was 87.2% with TTE plus CMR. Penetrance was age-dependent, reaching 100% in carriers older than 55 years. MYBPC3 p.G263* shares with most truncating pathogenic variants in this gene a late onset, relatively benign clinical course in the young, and high penetrance. Cardiac magnetic resonance could be a useful tool to evaluate carriers despite TTE results. Show less

Raised serum cholesterol concentration is a well-established risk factor in cardiovascular disease. In addition, genetic load may have an indirect influence on cardiovascular risk. Plant-based sterol-supplemented foods are recommended to help reduce the serum low-density lipoprotein cholesterol level. The objective was to analyse the influence of different polymorphisms in hypercholesterolemia patients following a dietary treatment with plant sterols. A randomised double-blind cross-over controlled clinical trial was carried out in 45 people (25 women). Commercial milk, containing 2.24 g of sterols, was ingested daily during a 3-week period, and then the same amount of skim milk, without sterols, was consumed daily during the 3-week placebo phase. Both phases were separated by a washout period of 2 weeks. At the beginning and end of each phase, blood draws were performed. Genes Show less

Recent exome sequencing studies identified filamin C ( A total of 448 HCM patients were next generation-sequenced (semiconductor chip technology) for the We provide a compelling evidence of the involvement of Show less

Mutations in at least 30 genes have been linked to hypertrophic cardiomyopathy (HCM). Due to the large size of the main HCM genes, Sanger sequencing is labor intensive and expensive. The purpose was to develop a next-generation sequencing (NGS) procedure for the main HCM genes. METHODS AND RESULTS: Multiplex amplification of the coding exons of MYH7,MYBPC3,TNNT2,TNNI3,ACTC1,TNNC1,MYL2,MYL3, and TPM1 was designated, followed by NGS with the Ion Torrent PGM (Life Technologies). A total of 8 pools containing DNA from HCM patients were sequenced in a 2-step approach. First, a total of 60 patients (validation cohort) underwent both PGM and Sanger sequencing for the 9 genes. No false-negative variants were found on NGS (100% sensitivity), and a specificity of 97% and 80% was achieved for single-nucleotide and insertion/deletion variants, respectively. Second, the PGM was used to search for mutations in a total of 76 cases not previously studied (discovery cohort). A total of 19 putative mutations were identified in the discovery pools, which were confirmed and assigned to specific patients on Sanger sequencing. An NGS procedure has been developed for the main sarcomeric genes that would facilitate the screening of large cohorts of patients. In addition, this procedure would facilitate the uncovering of rare gene variants on a population scale. Show less

Mutation of a sarcomeric gene is the most frequent cause of hypertrophic cardiomyopathy. For each such gene, however, previous studies have reported a range of different mutation frequencies, and clinical manifestations have been highly heterogeneous, both of which limit the use of genetic information in clinical practice. Our aim was to determine the frequency of mutations in the sarcomeric genes MYH7, MYBPC3, TNNT2, TNNI3, and TPM1 in a cohort of Spanish patients with hypertrophic cardiomyopathy. We used sequencing to analyze the coding regions of these five genes in 120 patients (29% with a family history) and investigated how the patient phenotype varied with the gene mutated. In total, 32 patients were found to have mutations: 10 in MYH7 (8%), 20 in MYBPC3 (16%), 2 in TNNT2, 1 in TPM1 and none in TNNI3. Overall, 61% of mutations had not been described before. Two patients had two mutations (i.e., double mutants). There was no difference in the mean age at diagnosis or the extent of the hypertrophy between those with MYH7 mutations and those with MYBPC3 mutations. Some 26% of patients had a mutation in one of the five sarcomeric genes investigated. More than half of the mutations had not been described before. The MYBPC3 gene was the most frequently mutated, followed by MYH7. No phenotypic differences were observed between carriers of the various mutations, which makes it difficult to use genetic information to stratify risk in these patients. Show less

Sudden death during sports activities, although unfrequent, is a tragic event with great impact on both the general and medical communities. The two commonest conditions leading to sudden cardiac death in young athletes are hyperthrophic cardiomyopathy (HCM), the main cause in the USA, and arrythmogenic right ventricular cardiomyopathy, which is the leading cause in Europe. We report the case of a 17-year-old football player with a pathological electrocardiography (ECG) in the pre-participation screening programme, highly suggestive of HCM, in which ECG study showed a septum thickness of 28 mm. Genetic analysis revealed R 495 W mutation in the 18 exon of the MyBPC3 (myosin-binding protein C) and sports activities were contraindicated. Two years later, septum thickness was 19.5 mm. Usefulness of 12-lead ECG, differential diagnosis between athlete's heart and HCM, and the stratification in patients with HCM are discussed. Show less