👤 Diana Sousa

This research investigated the potential therapeutic role of α-(phenylselanyl) acetophenone (PSAP) in the comorbidity of chronic pain and depression triggered by partial sciatic nerve ligation (PSNL). Male Swiss mice underwent PSNL surgery, and after a four-week period, they received either PSAP (1-50 mg/kg, administered intragastrically) or imipramine (IMI) (50 mg/kg) 30 min prior to behavioral assessments. Both PSAP and IMI effectively alleviated PSNL-induced hypersensitivity to pain and depressive-like symptoms, as demonstrated in forced swim and allodynia tests. Additionally, PSAP counteracted the elevated levels of lipid peroxidation and reactive oxygen species observed in the cortex and hippocampus following PSNL. These neuroprotective effects appear to be linked to PSAP's anti-inflammatory properties, as it downregulated the expression of pro-inflammatory markers such as NF-κB p65, TNF-α, and IDO mRNA in the affected brain regions. Furthermore, PSAP restored hippocampal BDNF mRNA levels, which had been diminished by nerve injury. Since inflammation is a common pathway in both chronic pain and depression, the findings indicate that PSAP holds promise as a treatment for this comorbid condition. Show less

Dyslipidemia remains a major, modifiable determinant of global stroke burden, accounting for more than one-fifth of ischemic strokes (IS) worldwide. Recent evidence has shifted emphasis from conventional lipid fractions to apolipoprotein B (ApoB)-containing lipoproteins, including lipoprotein(a) [Lp(a)], which more accurately reflect atherogenic particle burden than low-density lipoprotein cholesterol (LDL-C) alone and are increasingly used for stroke risk stratification. While the principle "the faster and the lower, the better" underpins dyslipidemia management, evidence-based, subtype-specific lipid strategies in stroke remain limited. Intensive LDL-C reduction significantly lowers recurrent IS risk; however, uniform lipid targets are often applied without accounting for stroke etiology. High-intensity statins remain first-line therapy, with pleiotropic benefits extending beyond LDL-C reduction. For statin intolerance or suboptimal response, ezetimibe and PCSK9 inhibitors provide potent, bleeding-neutral LDL-C lowering. Inclisiran and bempedoic acid broaden therapeutic options, although stroke-specific efficacy data are still pending. Lp(a)-lowering agents, including pelacarsen, olpasiran, and lepodisiran, are under active evaluation and may address residual cardiovascular risk. For triglyceride lowering, recent randomized evidence supports icosapent ethyl for reducing IS risk. In intracerebral hemorrhage (ICH), the optimal intensity and thresholds of lipid lowering remain uncertain, warranting individualized weighting of ischemic against hemorrhagic risk, particularly in patients with lobar ICH or suspected cerebral amyloid angiopathy (CAA). In such cases, hydrophilic statins, ezetimibe, or PCSK9 inhibitors may represent reasonable options. This review synthesizes current evidence and proposes a phenotype-guided, individualized framework for dyslipidemia management across stroke subtypes. Moving beyond uniform targets toward etiologic and genetically informed lipid modulation may improve post-stroke outcomes and refine individualized stroke prevention. Show less

Dihydromyricetin (DMY) presents itself as a promising therapeutic candidate due to its inhibitory effects on various receptor tyrosine kinases, prompting an investigation of its structural characteristics, molecular interactions, and biological activity across the FGFR, HER, PDGFR, and VEGFR families. Protein sequences and structures for FGFR1/2, HER2/3, PDGFRA/B, and VEGFR1/2 were retrieved from UniProt/PDB. DMY and reference inhibitors were docked to each kinase using AutoDock Vina. Anti-angiogenic activity was measured by HET-CAM assay with vessel metrics quantified via IKOSA CAM. MTT determined cytotoxicity (IC₅₀) and tumor-selectivity index in 4T1 and L929 cells; data (mean ± SEM) were analyzed by one-way ANOVA with Tukey's test (p < 0.005). DMY exhibited docking scores comparable to established inhibitors, achieved over 45 % inhibition of neovascularization in the HET-CAM assay at nanomolar concentrations, displayed a tumor-selectivity index of less than one in 4T1 versus L929 cells (mirroring many clinical chemotherapeutics), and, notably, coadministration with doxorubicin reduced in vitro cardiotoxicity markers. The high-affinity, multi-kinase binding profile and significant anti-angiogenic efficacy underscore DMY's multifunctional potential, while its tumor-selectivity index aligns with accepted therapeutic risk-benefit balances and its cardioprotective effect suggests a way to mitigate anthracycline toxicity. These findings indicate that DMY is a multifunctional agent exhibiting both antiangiogenic and cytotoxic properties, warranting further preclinical and clinical investigation. Show less

Chemically modified small interfering RNAs (siRNAs) are a promising drug class that silences disease-causing genes via mRNA degradation. Both siRNA-specific features (e.g. sequence, modification pattern, and structure) and target mRNA-specific factors contribute to observed efficacy. Systematically defining the relative contributions of siRNA sequence, structure, and modification pattern versus the native context of the target mRNA is necessary to inform design considerations and facilitate the widespread application of this therapeutic platform. To address this, we synthesized a panel of ∼1260 differentially modified siRNAs and evaluated their silencing efficiency against therapeutically relevant mRNAs (APP, BACE1, MAPT, and SNCA) using both reporter-based and native expression assays. Our results demonstrate that the siRNA modification pattern (e.g. level of 2'-O-methyl content) significantly impacts efficacy, while structural features (e.g. symmetric versus asymmetric configurations) do not. Furthermore, we observed substantial differences in the number of effective siRNAs identified per target. These target-specific differences in hit rates are largely mitigated when efficacy is tested in the context of a reporter assay, confirming that native mRNA-specific features influence siRNA performance. Key target-specific factors, including exon usage, polyadenylation site selection, and ribosomal occupancy, partially explained efficacy variability. These insights led to a proposed framework of parameters for optimizing therapeutic siRNA design. Show less

Childhood obesity and associated comorbidities in adulthood are of great concern worldwide. Evidence highlights the importance of lactation in later disease development. In this sense, obese children are at great risk of developing adult obesity, insulin resistance, type 2 diabetes, and cardiovascular disease at adulthood. PPARα activation during lactation promotes the expression of key enzymes involved in lipid oxidation, and it was associated with reduced adiposity in children. Therefore, we hypothesized that an animal model of childhood obesity, small litter (SL), would lead to the development of obesity and metabolic dysfunction in adulthood, which could be prevented by postnatal PPARα agonism. Wistar dams had their litter reduced, leading to postnatal overfeeding and obesity early in life. SL male pups were treated with fenofibrate, an PPARα agonist, during lactation, from postnatal day (PND) 1 until weaning (PND21), to verify whether PPARα activation prevents the developmental programming at adulthood (PND120). Childhood obesity induced by postnatal overfeeding leads to decreased markers for oxidative metabolism during infancy, leading to increased visceral adiposity and oxidative stress, insulin resistance, hepatic microvesicular steatosis, and increased fibroblast growth factor 21 (Fgf21) expression, followed by decreased brown adipose tissue (BAT) sympathetic nerve activity and decreased Fgfr1 hypothalamic expression in adulthood. Agonist-induced PPARα activation during lactation mitigated the development of aforementioned alterations in adulthood. Postnatal fenofibrate treatment prevents the developmental programming of visceral obesity, liver-associated metabolic dysfunction and BAT autonomic sympathetic hypoactivity in an animal model of childhood obesity. Show less

Pituitary tumours are relatively common, and familial in approximately 5% of cases. However, germline genetic contributions to pituitary tumour development are incompletely characterised. Preliminary evidence suggests pituitary tumours may be promoted by variants in pituitary organogenesis genes. Our study aimed to identify rare germline variants in pituitary organogenesis genes that may contribute to pituitary tumour development. A familial case of pituitary disease was investigated. We also examined 36 pituitary organogenesis genes in 134 individuals with pituitary tumours using a targeted next-generation sequencing panel, identifying and characterising variants with a population allele frequency < 0.05%. One patient with a prolactin-secreting pituitary tumour and his daughter with combined pituitary hormone deficiency shared a rare germline variant in FGFR1, c.386 A > C, p.(D129A). In our broader study, we identified an additional individual with the FGFR1 D129A variant and demonstrated enrichment compared to a control population derived from the Genome Aggregation Database (gnomAD). We also observed 66 rare germline variants in pituitary organogenesis genes amongst 54/134 individuals (40%). However, compared to control data, the study cohort exhibited no enrichment for other rare variants in FGFR1, FGF-related genes, or other pituitary embryogenesis genes. Our results suggest that the FGFR1 D129A variant may be associated with pituitary tumorigenesis but the role of other pituitary embryogenesis genes remains unclear. Additional independent cohorts and functional studies are required. Show less

Neurodegenerative disorders (NDDs) such as Alzheimer's (AD) and Parkinson's (PD) are on the rise, robbing people of their memories and independence. While risk factors such as age and genetics play an important role, exciting studies suggest that a diet rich in foods from plant origin may offer a line of defense. These kinds of foods, namely fruits and vegetables, are packed with a plethora of powerful bioactive secondary metabolites (SBMs), including terpenoids, polyphenols, glucosinolates, phytosterols and capsaicinoids, which exhibit a wide range of biological activities including antioxidant, antidiabetic, antihypertensive, anti-Alzheimer's, antiproliferative, and antimicrobial properties, associated with preventive effects in the development of chronic diseases mediated by oxidative stress such as type 2 diabetes mellitus, respiratory diseases, cancer, cardiovascular diseases, and NDDs. This review explores the potential of SBMs as Show less

Inflammatory breast cancer (IBC) is a rare and poorly characterized type of breast cancer with an aggressive clinical presentation. The biological mechanisms driving the IBC phenotype are relatively undefined-partially due to a lack of comprehensive, large-scale genomic studies and limited clinical cohorts. A retrospective analysis of 2457 patients with metastatic breast cancer who underwent targeted tumor-only DNA-sequencing was performed at Dana-Farber Cancer Institute. Clinicopathologic, single nucleotide variant (SNV), copy number variant (CNV) and tumor mutational burden (TMB) comparisons were made between clinically confirmed IBC cases within a dedicated IBC center versus non-IBC cases. Clinicopathologic differences between IBC and non-IBC cases were consistent with prior reports-including IBC being associated with younger age at diagnosis, higher grade, and enrichment with hormone receptor (HR)-negative and HER2-positive tumors. The most frequent somatic alterations in IBC involved Taken together, this study provides a comprehensive, clinically informed landscape of somatic alterations in a large cohort of patients with IBC. Our data support higher frequency of Show less

Prostate cancer (PCa) is an immunologically cold tumor and the molecular processes that underlie this behavior are poorly understood. In this study, we investigated a primary cohort of intermediate-risk PCa ( Show less

Liver-derived circulating factors deeply affect the metabolism of distal organs. Herein, we took advantage of the hepatocyte-specific PTEN knockout mice (LPTENKO), a model of hepatic steatosis associated with increased muscle insulin sensitivity and decreased adiposity, to identify potential secreted hepatic factors improving metabolic homeostasis. Our results indicated that protein factors, rather than specific metabolites, released by PTEN-deficient hepatocytes trigger an improved muscle insulin sensitivity and a decreased adiposity in LPTENKO. In this regard, a proteomic analysis of conditioned media from PTEN-deficient primary hepatocytes identified seven hepatokines whose expression/secretion was deregulated. Distinct expression patterns of these hepatokines were observed in hepatic tissues from human/mouse with NAFLD. The expression of specific factors was regulated by the PTEN/PI3K, PPAR or AMPK signaling pathways and/or modulated by classical antidiabetic drugs. Finally, loss-of-function studies identified FGF21 and the triad AHSG, ANGPTL4 and LECT2 as key regulators of insulin sensitivity in muscle cells and in adipocytes biogenesis, respectively. These data indicate that hepatic PTEN deficiency and steatosis alter the expression/secretion of hepatokines regulating insulin sensitivity in muscles and the lipid metabolism in adipose tissue. These hepatokines could represent potential therapeutic targets to treat obesity and insulin resistance. Show less

Dementia due to Alzheimer's disease (AD) is a complex neurodegenerative disorder, which much of heritability remains unexplained. At the clinical level, one of the most common physiological alterations is the slowing of oscillatory brain activity, measurable by electroencephalography (EEG). Relative power (RP) at the conventional frequency bands (i.e., delta, theta, alpha, beta-1, and beta-2) can be considered as AD endophenotypes. The aim of this work is to analyze the association between sixteen genes previously related with AD: APOE, PICALM, CLU, BCHE, CETP, CR1, SLC6A3, GRIN2 β, SORL1, TOMM40, GSK3 β, UNC5C, OPRD1, NAV2, HOMER2, and IL1RAP, and the slowing of the brain activity, assessed by means of RP at the aforementioned frequency bands. An Iberian cohort of 45 elderly controls, 45 individuals with mild cognitive impairment, and 109 AD patients in the three stages of the disease was considered. Genomic information and brain activity of each subject were analyzed. The slowing of brain activity was observed in carriers of risk alleles in IL1RAP (rs10212109, rs9823517, rs4687150), UNC5C (rs17024131), and NAV2 (rs1425227, rs862785) genes, regardless of the disease status and situation towards the strongest risk factors: age, sex, and APOE ɛ4 presence. Endophenotypes reduce the complexity of the general phenotype and genetic variants with a major effect on those specific traits may be then identified. The found associations in this work are novel and may contribute to the comprehension of AD pathogenesis, each with a different biological role, and influencing multiple factors involved in brain physiology. Show less

Hypertrophic cardiomyopathy (HCM) is characterized by unexplained left ventricular hypertrophy (LVH) and is one of the major causes of sudden cardiac death (SCD). An exon-targeted gene sequencing strategy was used to investigate the association of functional variants in sarcomeric genes (MYBPC3, MYH7 and TNNT2) with severe LVH and other SCD-related risk factors in Brazilian HCM patients. Clinical data of 55 HCM patients attending a Cardiology Hospital (Sao Paulo city, Brazil) were recorded. Severe LVH, aborted SCD, family history of SCD, syncope, non-sustained ventricular tachycardia and abnormal blood pressure in response to exercise were evaluated as SCD risk factors. Blood samples were obtained for genomic DNA extraction and the exons and untranslated regions of the MYH7, MYBPC3 and TNNT2 were sequenced using Nextera® and MiSEq® reagents. Variants were identified and annotated using in silico tools, and further classified as pathogenic or benign according to the American College of Medical Genetics and Genomics guidelines. Variants with functional effects were identified in MYBPC3 (n = 9), MYH7 (n = 6) and TNNT2 (n = 4). The benign variants MYBPC3 p.Val158Met and TNNT2 p.Lys263Arg were associated with severe LVH (p < 0.05), and the MYH7 p.Val320Met (pathogenic) was associated with family history of SCD (p = 0.037). Increased risk for severe LVH was found in carriers of MYBPC3 Met158 (c.472 A allele, OR = 13.5, 95% CI = 1.80-101.12, p = 0.011) or combined variants (MYBPC3, MYH7 and TNNT2: OR = 12.39, 95% CI = 2.14-60.39, p = 0.004). Carriers of TNNT2 p.Lys263Arg and combined variants had higher values of septum thickness than non-carriers (p < 0.05). Molecular modeling analysis showed that MYBPC3 158Met reduces the interaction of cardiac myosin-binding protein C (cMyBP-C) RASK domain (amino acids Arg215-Ala216-Ser217-Lys218) with tropomyosin. In conclusion, the variants MYBPC3 p.Val158Met, TNNT2 p.Lys263Arg and MYH7 p.Val320Met individually or combined contribute to the risk of sudden cardiac death and other outcomes of hypertrophic cardiomyopathy. Show less

In vitro 3D culture models have emerged in the cancer field due to their ability to recapitulate characteristics of the in vivo tumor. Herein, we described the establishment and characterization of 3D multicellular spheroids using ovarian cancer cells (SKOV-3) in co-culture with mesenchymal cells (MUC-9) or fibroblasts (CCD27-Sk). We demonstrated that SKOV-3 cells in co-culture were able to form regular and compact spheroids with diameters ranging from 300 to 400 µm and with a roundness close to 1.0 regardless of the type of stromal cell used. In the 3D culture an increase was not observed in spheroid diameter nor was there significant cell growth. What is more, the 3D co-cultures presented an up regulation of genes related to tumorigenesis, angiogenesis and metastases (MMP2, VEGFA, SNAI1, ZEB1 and VIM) when compared with 2D and 3D monoculture. As expected, both 3D cultures (mono and co-cultures) exhibited a higher Paclitaxel chemoresistance when compared to 2D condition. Although we did not observe differences in the Paclitaxel resistance between the 3D mono and co-cultures, the gene expression results indicate that the presence of mesenchymal cells and fibroblasts better recapitulate the in vivo tumor microenvironment, being able, therefore, to more accurately evaluate drug efficacy for ovarian cancer therapy. Show less

Sudden cardiac death (SCD) risk stratification in dilated cardiomyopathy (DCM) has been based on left ventricular ejection fraction (LVEF), even though SCD may occur with LVEF > 35%. Family history of unexplained SCD, especially in the young, raises concern about potential inheritable risk factors. It remains largely unknown how genetic tests can be integrated into clinical practice, particularly in the selection of implantable cardioverter defibrillator (ICD) candidates. We aimed to assess the diagnostic yield of genetic testing in DCM patients with a class I recommendation for ICD implantation, based on current guidelines. We included ambulatory stable adult patients with idiopathic or familial DCM with previously implanted ICD. Molecular analysis included 15 genes ( We evaluated 21 patients, 12 (57%) males and 9 (43%) with familial DCM, including 3 (14%) with a family history of premature unexplained SCD. Mean age at DCM diagnosis was 40 ± 2 years, and mean age at ICD implantation was 50 ± 12 years. LVEF was 27 ± 9%, and LV end-diastolic diameter was 65 ± 7 mm. Genetic variants were found in six (29%) patients, occurring in 5 genes: In patients with DCM and ICD, genetic variants could be identified in a significant proportion of patients in several genes, highlighting the potential role of genetics in DCM SCD risk stratification. Show less

Dilated cardiomyopathy (DCM) is a disease of the heart muscle characterized by ventricular dilatation and impaired systolic function. Familial forms account for 30-50% of cases. Autosomal dominant inheritance is the predominant pattern of transmission. Causal genetic variants have been identified in several genes and molecular diagnosis has implications for genetic counseling and risk stratification. We aimed to estimate the frequency of genetic variants and the molecular basis of DCM in Portugal. We performed a multicenter study of unrelated patients, recruited between 2013 and 2014. Variants in 15 genes were screened using PCR with direct sequencing (next-generation sequencing with at least 30-fold coverage combined with Sanger sequencing). A total of 107 patients were included, 64 (60%) men, mean age at diagnosis 38±13 years, with 48 (45%) familial cases. In total, 31 rare variants in eight genes (mainly in MYBPC3, TNNT2 and LMNA) were identified, in 28 patients (26%). Only four variants had been previously described in association with DCM, 11 with hypertrophic cardiomyopathy, and nine variants were novel. Four variants were likely pathogenic and the remainder were of uncertain significance. We found no major differences in the main clinical and imaging characteristics between patients with or without rare variants and patients with likely pathogenic variants. Our results reflect the complexity and diversity of DCM genetics. For better interpretation of the pathogenicity of the variants found and their causative roles in DCM, molecular cascade screening of families is imperative. Further insight into genotype-phenotype correlations and risk stratification is desirable. Show less

Apolipoprotein gene polymorphism has an important role in lipid metabolism and in the development of cerebro- and cardio-vascular disease (CCVD), including dementia. Dyslipidemia and hemostatic abnormalities are key risk factors associated with athero-sclerotic events preceding CCVD. The aim of this study was to evaluate the possible relationships of various apolipoprotein-species with hemostatic parameters and cognitive function. Lipid profile, gene polymorphism, coagulation markers, and mini-mental state examination (MMSE) scores were assessed in 109 dys-lipidemic subjects and in 107 healthy control volunteers. Thrombin-activatable fibrinolysis inhibitor (TAFI) plasma levels were significantly higher in apolipoprotein-E2 (apoE2) patients when compared to other apoE forms. The apoA5 -1131T>C polymorphism was associated with elevated D-dimer concentration in dyslipidemic TT homozygous individuals. MMSE did not correlate with lipid or coagulation profile. These data suggest that apoE and apoA5 variants have an effect on hemostatic parameters, but they neither influence nor predict cognitive performance in non-demented individuals. Show less

Polymorphisms in apolipoprotein A5 gene (APOA5) have been associated with higher triglyceride levels in many populations. The aim of the study was to determine the allelic and genotypic distribution of the APOA5 -1131T>C polymorphism and to identify the association of the genetic variant and the risk for dyslipidemia. We genotyped 109 dyslipidemic subjects and 107 controls. The total cholesterol, triglycerides and HDL-c were determined enzymatically. Comparison of means among groups was calculated by ANOVA. Significant differences among groups were evaluated by Student-Newman-Keuls test. The minor allele C was more frequent in dyslipidemic subjects than controls (p=0.019) and confers an increased individual risk for dyslipidemia (OR=1.726, CI 95%=1.095-2.721). The genotype analysis by gender showed that this allele was more frequent in dyslipidemic males (p=0.037; OR=2.050, CI 95%=1.042-4.023). When participants were analyzed according to genotypes TT and TC/CC, C-carriers presented higher cholesterol and triglycerides levels than TT homozygous (p=0.046 and 0.049, respectively). The allele C confers higher total cholesterol and triglycerides levels in dyslipidemic adults. The APOA5 -1131T>C polymorphism is associated with dyslipidemia in male subjects. Show less

Liver X receptors (Lxrα and Lxrβ) are ligand-dependent nuclear receptors critical for ventral midbrain neurogenesis in vivo. However, no endogenous midbrain Lxr ligand has so far been identified. Here we used LC/MS and functional assays to identify cholic acid as a new Lxr ligand. Moreover, 24(S),25-epoxycholesterol (24,25-EC) was found to be the most potent and abundant Lxr ligand in the developing mouse midbrain. Both Lxr ligands promoted neural development in an Lxr-dependent manner in zebrafish in vivo. Notably, each ligand selectively regulated the development of distinct midbrain neuronal populations. Whereas cholic acid increased survival and neurogenesis of Brn3a-positive red nucleus neurons, 24,25-EC promoted dopaminergic neurogenesis. These results identify an entirely new class of highly selective and cell type-specific regulators of neurogenesis and neuronal survival. Moreover, 24,25-EC promoted dopaminergic differentiation of embryonic stem cells, suggesting that Lxr ligands may thus contribute to the development of cell replacement and regenerative therapies for Parkinson's disease. Show less

Type 2 diabetes mellitus is a metabolic, vascular, and neuropathic disease with a high risk of atherosclerotic events due to dyslipidemic states. Polymorphisms in Apolipoprotein A5 gene (APOA5) have been associated with increased triglyceride levels in many different populations. This study aimed to identify the frequencies of the APOA5 -1131T>C and SW19 polymorphisms and evaluate their effects on lipid levels in patients with type 2 diabetes. Genotyping of APOA5 -1131T>C and SW19 polymorphisms was performed by PCR-RFLP in 146 diabetic patients and in controls (n = 173), from 30 to 80 years of age. Diabetic patients were divided into two groups: patients not treated with lipid lowering drugs (group G1; n = 62) and those treated with lipid lowering drugs (group G2, n = 84). Lipids and lipoproteins were determined enzymatically. Among participants not treated with lipid-lowering drugs (diabetics G1 and controls; n = 235), the -1131C was associated with lower LDLc levels (p = 0.015). In the diabetic patients, the 19W allele was associated with higher triglyceride levels (p = 0.004). In G1 diabetic patients, the combined analysis of APOA5 -1131T>C and SW19 polymorphisms showed that [TC or CC] + SS carriers presented lower total cholesterol levels than did other genotype combinations (p = 0.049). It could therefore be concluded that APOA5 -1131T>C and SW19 polymorphisms influence lipid levels in type 2 diabetic patients. Show less

Apolipoprotein A5 (APOA5) and apolipoprotein E (APOE) play important roles in the metabolism of cholesterol and triglycerides. The aim of this study was to determine the allelic and genotypic distributions of the APOA5-1131T>C (rs 662799) and the APOE HhaI polymorphisms and to identify the association of both individual and combined APOA5-APOE genetic variants and the risk for dyslipidemia in children and adolescents. We genotyped 53 dyslipidemic and 77 normolipidemic individuals. The total cholesterol, triglycerides and HDL cholesterol were determined enzymatically. For APOA5 polymorphism, the presence of the allele C confers an individual risk for dyslipidemia (OR = 2.38, 95% CI = 1.15-4.89; P = 0.018). No significant differences were observed for lipid parameters among the APOA5 groups, except for a higher value of HDLc (P = 0.024) in C-carriers. The allelic and genotypic frequencies of APOE polymorphism were similar between groups and did not increase the susceptibility for dyslipidemia. None of the combined APOA5-APOE polymorphisms increased risk for dyslipidemia. We demonstrated an association between APOA5-1131T>C polymorphism and dyslipidemia in children and adolescents. This finding may be useful to guide new studies with genetic markers down a path toward a better characterization of the genetic risk factors for dyslipidemia and atherosclerotic diseases. Show less

Metachondromatosis (MC) is a rare, autosomal dominant, incompletely penetrant combined exostosis and enchondromatosis tumor syndrome. MC is clinically distinct from other multiple exostosis or multiple enchondromatosis syndromes and is unlinked to EXT1 and EXT2, the genes responsible for autosomal dominant multiple osteochondromas (MO). To identify a gene for MC, we performed linkage analysis with high-density SNP arrays in a single family, used a targeted array to capture exons and promoter sequences from the linked interval in 16 participants from 11 MC families, and sequenced the captured DNA using high-throughput parallel sequencing technologies. DNA capture and parallel sequencing identified heterozygous putative loss-of-function mutations in PTPN11 in 4 of the 11 families. Sanger sequence analysis of PTPN11 coding regions in a total of 17 MC families identified mutations in 10 of them (5 frameshift, 2 nonsense, and 3 splice-site mutations). Copy number analysis of sequencing reads from a second targeted capture that included the entire PTPN11 gene identified an additional family with a 15 kb deletion spanning exon 7 of PTPN11. Microdissected MC lesions from two patients with PTPN11 mutations demonstrated loss-of-heterozygosity for the wild-type allele. We next sequenced PTPN11 in DNA samples from 54 patients with the multiple enchondromatosis disorders Ollier disease or Maffucci syndrome, but found no coding sequence PTPN11 mutations. We conclude that heterozygous loss-of-function mutations in PTPN11 are a frequent cause of MC, that lesions in patients with MC appear to arise following a "second hit," that MC may be locus heterogeneous since 1 familial and 5 sporadically occurring cases lacked obvious disease-causing PTPN11 mutations, and that PTPN11 mutations are not a common cause of Ollier disease or Maffucci syndrome. Show less

Left ventricular noncompaction (LVNC) is a rare and potentially progressive cardiomyopathy, characterized by the persistence of multiple trabeculations and deep intratrabecular recesses in the ventricular myocardium. Although two-dimensional and color Doppler echocardiography are the most useful diagnostic modalities, cardiac magnetic resonance imaging has proved to have high sensitivity and specificity in the diagnosis of this anomaly. To characterize the clinical and imaging features of LVNC in a pediatric population and to assess their evolution. We performed a retrospective chart review of five pediatric patients with LVNC, followed at Coimbra Pediatric Hospital between January 1999 and December 2007. Median age at presentation was five months (ranging from one day to 13 years), and they were mainly male (1.5:1). Two of the children had a family history of sudden death. In one case the clinical presentation was cardiac arrest due to ventricular fibrillation and in three others, congestive cardiac failure. None of the five cases had associated congenital cardiac anomalies. Involvement of the ventricular apical region was found in all cases. Four children additionally had ventricular dysfunction which improved with diuretic and vasodilator therapy. Mean follow-up was 34 months, ranging from six months to seven years. In one case a change in the morphological phenotype was noted, from a dilated to a hypertrophic form. In this case and in the child's father a mutation in the MYBPC3 gene was identified, which is associated with hypertrophic cardiomyopathy. No thromboembolic phenomena or deaths occurred during the study period. In the pediatric population, congestive cardiac failure is the most common clinical presentation of LVNC, which can coexist with other cardiomyopathies, particularly dilated and hypertrophic forms. The sample presented in this analysis is statistically non-significant due to its limited size and the authors highlight the need for larger prospective studies in the pediatric population in order to clarify this disease and its diagnostic criteria. Show less

Juvenile neuronal ceroid lipofuscinosis (JNCL), also known as Batten disease, is a fatal inherited neurodegenerative disorder. The major clinical features of this disease are vision loss, seizures and progressive cognitive and motor decline starting in childhood. Mutations in CLN3 are known to cause the disease, allowing the generation of mouse models that are powerful tools for JNCL research. In this study, we applied behavioural phenotyping protocols to test for early behavioural alterations in Cln3(Deltaex7/8) knock-in mice, a genetic model that harbours the most common disease-causing CLN3 mutation. We found delayed acquisition of developmental milestones, including negative geotaxis, grasping, wire suspension time and postural reflex in both homozygous and heterozygous Cln3(Deltaex7/8) preweaning pups. To further investigate the consequences of this neurodevelopmental delay, we studied the behaviour of juvenile mice and found that homozygous and heterozygous Cln3(Deltaex7/8) knock-in mice also exhibit deficits in exploratory activity. Moreover, when analysing motor behaviour, we observed severe motor deficits in Cln3(Deltaex7/8) homozygous mice, but only a mild impairment in motor co-ordination and ambulatory gait in Cln3(Deltaex7/8) heterozygous animals. This study reveals previously overlooked behaviour deficits in neonate and young adult Cln3(Deltaex7/8) mice indicating neurodevelopmental delay as a putative novel component of JNCL. Show less

Control over progenitor proliferation and neurogenesis remains a key challenge for stem cell neurobiology and a prerequisite for successful stem cell replacement therapies for neurodegenerative diseases like Parkinson's disease (PD). Here, we examined the function of two nuclear receptors, liver X receptors (Lxralpha and beta) and their ligands, oxysterols, as regulators of cell division, ventral midbrain (VM) neurogenesis, and dopaminergic (DA) neuron development. Deletion of Lxrs reduced cell cycle progression and VM neurogenesis, resulting in decreased DA neurons at birth. Activation of Lxrs with oxysterol ligands increased the number of DA neurons in mouse embryonic stem cells (ESCs) and in wild-type but not Lxralphabeta(-/-) VM progenitor cultures. Likewise, oxysterol treatment of human ESCs (hESCs) during DA differentiation increased neurogenesis and the number of mature DA neurons, while reducing proliferating progenitors. Thus, Lxr ligands may improve current hESC replacement strategies for PD by selectively augmenting the generation of DA neurons. Show less

Hypertriglyceridemia constitutes an independent risk factor for coronary disease. The gene apolipoprotein A5 (ApoA5) is a newly discovered member in the ApoA1/C3/A4/A5 cluster, and its product, apolipoprotein A5, influences on triglycerides through an unknown mechanism. Recently, there have been described the clinical consequences and the functional effects over more than 10 variants of the ApoA5 gene, associated with atherosclerosis. In different studies carried out in different ethnic groups, it has been observed a great variation in the distribution of the ApoA5 genotypes for the respective polymorphisms. Different authors have described associations among the ApoA5 gene, high triglyceride concentrations and an increase in the cardiovascular risk. In this context, the ApoA5 gene is considered as a probable biochemical and genetic marker of increased triglyceride concentrations and also a risk factor of coronary disease in some populations. Show less

Apolipoprotein A5 gene (APOA5) has been shown to modulate plasma triglyceride concentrations. The apolipoprotein E gene (APOE) has been implicated in cholesterol and triglyceride homeostasis in humans and plays an important role in atherogenesis. The aim of this study was to determine the genotypic distribution of the APOA5 -1131T>C and APOE polymorphisms and to identify the combined association of these variants between patients with and without severe hypertriglyceridemia (HTG). We genotyped 96 individuals who had reached plasma TG concentrations of more than 10 mmol/L and 225 ischemic patients without severe HTG. Minor allele carriers were significantly more frequent in HTG group for all three polymorphisms (APOA5, APOE2 and APOE4). Adjusted individual risks for severe HTG were: APOA5 -1131C, OR=4.1 (95%CI:2.02-8.24); APOE2, OR=1.6 (95%CI:0.73-3.58); APOE4, OR=3.0 (95%CI:1.68-5.86). Adjusted risks for APOA5-APOE combinations were: APOA5 -1131C/APOE2, OR=45.2 (95%CI:4.92-415.5); APOA5 -1131C/APOE4, OR=6.4 (95%CI:2.28-18.01). These data provide evidence that APOA5 -1131T>C polymorphism is associated with risk for severe HTG. Furthermore, this effect is strongly increased when -1131C variant is combined with APOE variants. Show less

Familial amyloidotic polyneuropathy (FAP) is a neurodegenerative disorder characterized by the extracellular deposition of transthyretin (TTR), especially in the PNS. Given the invasiveness of nerve biopsy, salivary glands (SG) from FAP patients were used previously in microarray analysis; mitogen-activated protein (MAP) kinase phosphatase 1 (MKP-1) was down-regulated in FAP. Results were validated by RT-PCR and immunohistochemistry both in SG and in nerve biopsies of different stages of disease progression. MKP-3 was also down-regulated in FAP SG biopsies. Given the relationship between MKPs and MAPKs, the latter were investigated. Only extracellular signal-regulated kinases 1/2 (ERK1/2) displayed increased activation in FAP SG and nerves. ERK1/2 kinase (MEK1/2) activation was also up-regulated in FAP nerves. In addition, an FAP transgenic mouse model revealed increased ERK1/2 activation in peripheral nerve affected with TTR deposition when compared to control animals. Cultured rat Schwannoma cell line treatment with TTR aggregates stimulated ERK1/2 activation, which was partially mediated by the receptor for advanced glycation end-products (RAGE). Moreover, caspase-3 activation triggered by TTR aggregates was abrogated by U0126, a MEK1/2 inhibitor, indicating that ERK1/2 activation is essential for TTR aggregates-induced cytotoxicity. Taken together, these data suggest that abnormally sustained activation of ERK in FAP may represent an early signaling cascade leading to neurodegeneration. Show less