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Mitochondrial dysfunction, oxidative stress, and neuroinflammation play a critical role in the occurrence and progression of Alzheimer's disease (AD). MicroRNAs (miRNAs) have been studied recently as potential therapeutic approaches for AD. In this study, we examined the function and underlying mechanism of microRNA-25802 (miR-25802), a newly discovered miRNA in an AD model. In order to evaluate the levels of oxidative stress, mitochondrial damage and neuroinflammation in neuroblastoma cells, four experimental groups were created: control group (neuroblastoma cells, SH-SY5Y), amyloid beta (Aβ)-induced neuroblastoma cells (SY5Y-Aβ), small extracellular vesicles (sEVs)-only group and miR-25802-loaded small extracellular vesicles (sEV-miR25802) administered group. Neuroinflammation, oxidative stress, mitochondrial damage, tau hyperphosphorylation, and Aβ accumulation were evaluated in Aβ-induced neuroblastoma cells. Oxidative stress was analyzed by measuring reactive oxygen species (ROS), malondialdehyde (MDA), lactate dehydrogenase (LDH), superoxide dismutase (SOD), and glutathione peroxidase 1 (GPX1). Inflammatory markers such as tumor necrosis factor-alpha (TNF-α), intercellular adhesion molecule 1 (ICAM1), and brain-derived neurotrophic factor (BDNF) mRNA levels, a neurotrophic factor, were evaluated by RT-qPCR. Neurofilament light chain (NfL), vascular endothelial growth factor-A (VEGF-A), macrophage migration inhibitory factor (MIF), monocyte chemoattractant protein-1 (MCP-1) and cytochrome c (Cyt-c), mitochondrial transcription factor A (TFAM), PTEN-induced kinase 1 (PINK1) and dynamin-1-like protein (DNM1L) protein levels were determined by ELISA. Mechanistically, sEV-miR25802 were shown to provide anti-inflammatory and neuroprotective effects by regulating neuroinflammation, mitochondrial dysfunction, and oxidative stress. These findings reveal the regulatory role of miR-25802 on neuroinflammation, mitochondrial damage, and oxidative stress and suggest that it may be a potential therapeutic target for AD. Show less

In this study, we investigated the therapeutic potential of miR-206-3p delivered via small extracellular vesicles (sEVs) in an in vitro Alzheimer's disease model using SH-SY5Y human neuroblastoma cells treated with amyloid beta (Aβ). The sEV-miR-206-3p complexes were successfully loaded with miR-206-3p (∼0.001 copies per particle) without disrupting vesicle integrity or inducing cytotoxicity at the optimized concentration of 5 μg/mL. Aβ treatment significantly increased oxidative stress markers (ROS, MDA, LDH) and decreased antioxidant enzyme activity (SOD), while GPX1 showed an opposite trend. Furthermore, Aβ elevated proinflammatory gene expression (ICAM1, TNF-α) and reduced neuroprotective BDNF levels, induced mitochondrial dysfunction (increased Cyt-c, PINK1, DNM1L; decreased TFAM), impaired synaptic proteins (CPLX2, ROR1), and promoted tau phosphorylation and Aβ accumulation. Treatment with sEV-miR-206-3p effectively mitigated these alterations, reducing oxidative stress, suppressing neuroinflammatory responses, restoring mitochondrial function and synaptic protein levels, and attenuating tau and Aβ pathology. These findings demonstrate that miR-206-3p-loaded sEVs protect neuroblastoma cells from Aβ-induced neurodegenerative processes, highlighting their potential as a novel drug delivery system for neuroprotection. Show less

Carbamoyl phosphate synthetase 1 (CPS1) and ornithine transcarbamylase (OTC) deficiencies are rare urea cycle disorders, which can lead to life-threatening hyperammonemia. Liver transplantation (LT) provides a cure and offers an alternative to medical treatment and life-long dietary restrictions with permanent impending risk of hyperammonemia. Nevertheless, in most patients, metabolic aberrations persist after LT, especially low plasma citrulline levels, with questionable clinical impact. So far, little is known about these alterations and there is no consensus, whether l-citrulline substitution after LT improves patients' symptoms and outcomes. In this multicentre, retrospective, observational study of 24 patients who underwent LT for CPS1 (n = 11) or OTC (n = 13) deficiency, 25% did not receive l-citrulline or arginine substitution. Correlation analysis revealed no correlation between substitution dosage and citrulline levels (CPS1, p = 0.8 and OTC, p = 1). Arginine levels after liver transplantation were normal after LT independent of citrulline substitution. Native liver survival had no impact on mental impairment (p = 0.67). Regression analysis showed no correlation between l-citrulline substitution and failure to thrive (p = 0.611) or neurological outcome (p = 0.701). Peak ammonia had a significant effect on mental impairment (p = 0.017). Peak plasma ammonia levels correlate with mental impairment after LT in CPS1 and OTC deficiency. Growth and intellectual impairment after LT are not significantly associated with l-citrulline substitution. Show less

Dyggve-Melchior-Clausen dysplasia (DMC) and Smith-McCort dysplasia (SMC types 1 and 2) are rare spondylo-epi-metaphyseal dysplasias with identical radiological and clinical findings. DMC and SMC type 1 are allelic disorders caused by homozygous or compound heterozygous variants in DYM, while biallelic causative variants in RAB33B lead to SMC type 2. The terminology "skeletal golgipathies" has been recently used to describe these conditions, highlighting the pivotal role of these two genes in the organization and intracellular trafficking of the Golgi apparatus. In this study, we investigated 17 affected individuals (8 males, 9 females) from 10 unrelated consanguineous families, 10 diagnosed with DMC and seven with SMC type 2. The mean age at diagnosis was 9.61 ± 9.72 years, ranging from 20 months to 34 years, and the average height at diagnosis was 92.85 ± 15.50 cm. All patients exhibited variable degrees of short trunk with a barrel chest, protruding abdomen, hyperlordosis, and decreased joint mobility. A total of nine different biallelic variants were identified, with six being located in the DYM gene and the remaining three detected in RAB33B. Notably, five variants were classified as novel, four in the DYM gene and one in the RAB33B gene. This study aims to comprehensively assess clinical, radiological, and molecular findings along with the long-term follow-up findings in 17 patients with DMC and SMC type 2. Our results suggest that clinical symptoms of the disorder typically appear from infancy to early childhood. The central notches of the vertebral bodies were identified as early as 20 months and tended to become rectangular, particularly around 15 years of age. Pseudoepiphysis was observed in five patients; we believe this finding should be taken into consideration when evaluating hand radiographs in clinical assessments. Furthermore, our research contributes to an enhanced understanding of clinical and molecular aspects in these rare "skeletal golgipathies," expanding the mutational spectrum and offering insights into long-term disease outcomes. Show less

Genetic etiologies of autism spectrum disorders (ASD) are complex, and the genetic factors identified so far are very diverse. In complex genetic diseases such as ASD, de novo or inherited chromosomal abnormalities are valuable findings for researchers with respect to identifying the underlying genetic risk factors. With gene mapping studies on these chromosomal abnormalities, dozens of genes have been associated with ASD and other neurodevelopmental genetic diseases. In the present study, we aimed to idenitfy the causative genetic factors in patients with ASD who have an apparently balanced chromosomal translocation in their karyotypes. For mapping the broken genes as a result of chromosomal translocations, we performed whole genome DNA sequencing. Chromosomal breakpoints and large DNA copy number variations (CNV) were determined after genome alignment. Identified CNVs and single nucleotide variations (SNV) were evaluated with VCF-BED intersect and Gemini tools, respectively. A targeted resequencing approach was performed on the JMJD1C gene in all of the ASD cohorts (220 patients). For molecular modeling, we used a homology modeling approach via the SWISS-MODEL. We found that there was no contribution of the broken genes or regulator DNA sequences to ASD, whereas the SNVs on the JMJD1C, CNKSR2 and DDX11 genes were the most convincing genetic risk factors for underlying ASD phenotypes. Genetic etiologies of ASD should be analyzed comprehensively by taking into account of the all chromosomal structural abnormalities and de novo or inherited CNV/SNVs with all possible inheritance patterns. Show less

We report two newborns with female external genitalia and bilateral inguinal swelling who were diagnosed with 17β-hydroxysteroid dehydrogenase type 3 deficiency, a rare cause of 46,XY disorder of sexual development. The first case had normal clitoral size and vaginal and urethral openings, palpable gonads in the inguinal region, low testosterone, and low levels of basal and GNRH-stimulated gonadotropin. The second case had similar external genitalia, low testosterone but borderline basal and normal stimulated gonadotropin levels. Low testosterone/androstenedione ratios (0.22 and 0.24, respectively; normal, >0.8) after human chorionic gonadotropin stimulation indicated 17β-hydroxysteroid dehydrogenase type 3 deficiency. HSD17B3 sequencing revealed a homozygous novel mutation (c.464A>C, p.H155P) in exon 6 in the first case and homozygous c.239G>A (p.R80Q) in exon 3 in the second. Show less