👤 Basit Latief Jan

Efficient, spatially selective delivery of adeno-associated virus (AAV) therapeutics to deep brain structures remains a major challenge to gene therapy for Alzheimer's disease (AD), owing to limited transport across the blood-brain barrier (BBB) and poor penetration to target neurons. Here, we establish an integrated, noninvasive imaging and therapy platform that combines microbubble-enhanced focused ultrasound (MB-FUS) with positron emission tomography/computed tomography (PET/CT) to transiently modulate the BBB, enhance region-specific AAV delivery following systemic dosing, and longitudinally track transduction in vivo. Optimized MB-FUS achieved targeted hippocampal delivery of systemically administered AAV9 in healthy mice, resulting in a 10-fold enhancement of neuronal transduction as compared to non-FUS controls. Importantly, longitudinal PET reporter gene imaging in the 5xFAD AD model demonstrated robust brain AAV transduction that remained stable for at least seven months. Finally, to assess therapeutic impact, we used brain-derived neurotrophic factor (BDNF) as a test cargo. MB-FUS-facilitated delivery elevated BDNF expression in targeted regions and produced short-term improvements in synaptic signaling in 5xFAD mice. Collectively, these results highlight MB-FUS as a next-generation delivery platform to overcome barriers to AAV therapeutic delivery in Alzheimer's disease and position longitudinal PET assessment as a critical, translatable tool for monitoring and optimizing gene therapy. Show less

Neurodegenerative diseases, which pose significant challenges for effective treatment, often involve risk variants of lysosomal gene products that disrupt lysosomal function, leading to the accumulation of indigestible materials and damage to brain cells. The lysosome is a degradative organelle and a signaling hub that senses nutrient availability. How lysosomal dysfunction contributes to neurodegenerative diseases is an important open question. In this study, we identified CLN3 (ceroid lipofuscinosis, neuronal 3), an endolysosomal protein that is linked to Batten disease, as an evolutionarily conserved protein that facilitates lysosomal chloride efflux. Additionally, we report that a natural compound with anti-inflammatory properties-the curcumin analog C1, which is a TFEB (transcription factor EB) activator-could enhance CLN3 activity and improve lysosomal function. These findings provide new insight into the role of CLN3 in lysosomal ion homeostasis and raise the possibility that modulation of the TFEB-CLN3 signaling axis may hold therapeutic potential for lysosomal storage disorders. Show less

Sjögren's Syndrome (SS) and Type 1 Diabetes (T1D) are autoimmune disorders that can co-occur in patients, leading to complex clinical presentations. Despite observational evidence of their co-occurrence, the underlying genetic mechanisms remain poorly understood. To investigate the shared genetic factors and pathways between SS and T1D, we conducted a comprehensive analysis using multiomic approaches. Conditional and conjunctional false discovery rate analyses were performed to identify genetic polygenicity and overlap between the two diseases. Functional annotation and pathway analysis identified SNPs with regulatory potential. Furthermore, Mendelian Randomization (MR) analyses were employed to investigate causal associations between gene expression and disease risk. Single-cell differential gene expression analysis was also employed to validate the associations of risk genes with T1D and SS. Our analysis identified 36 shared loci, revealing common genetic enrichment between SS and T1D. Functional annotation and pathway analysis revealed 52 credible genes involved in cysteine-related processes, apoptotic signalling and immune responses. MR analyses revealed that AC007283.5 was positively linked with both SS and T1D, while PLEKHM1 and CRHR1-T1 were negatively associated. Additionally, CERS2 was positively associated with SS, DEF6 was positively associated with T1D, and KANSL1-AS1 was negatively associated with T1D, indicating the presence of complex regulatory mechanisms. Moreover, Single-cell differential gene expression analysis confirmed the dysregulation of risk genes in SS and T1D. This study identified shared genetic factors and pathways underlying SS and T1D, highlighting cysteine-related processes and apoptotic signalling. The findings underscore the complex interplay of autoimmunity and the need for targeted treatments addressing their common mechanisms. Show less

We present multimodality imaging of ventricular septal calcification. A 38-year-old man with asymptomatic gene-positive hypertrophic cardiomyopathy was found to have extensive dystrophic calcification of the ventricular septum. We hypothesized that the extensive ventricular septal calcification would represent an area of severe myocardial fibrosis, resulting in calcification secondary to postsurgical (septal myectomy) changes. Calcification of the ventricular septum is a rare finding, not previously described following septal myectomy, that should prompt a comprehensive evaluation and follow-up with multimodality imaging and testing. Show less

Owing to the recognition of previously unknown pathogenic gene variants and reclassification of longer-known variants, gene distribution in patients with hypertrophic cardiomyopathy (HCM) is ever-changing. Conflicting data make the role of genotype in risk stratification unclear. We evaluated genotype distribution and genotype-phenotype correlations in all adult patients with HCM seen at our HCM Center of Excellence from March 31, 2010, to April 30, 2023. We also evaluated a composite outcome, including all-cause mortality, stroke, implantable cardioverter-defibrillator placement, heart failure hospitalization, left ventricular assist device implantation, heart transplantation, septal myectomy, and alcohol septal ablation, based on genotype status. All-cause mortality was separately analyzed. Of 827 patients with HCM, genotyping was completed in 754 (91.2 %). We identified 202 (27 %) genotype-positive (Gen-P), 163 (22 %) variant of unknown significance (VUS), and 389 (51 %) genotype-negative (Gen-N) patients. Mean ages were 47, 57, and 58 years, respectively. The most common gene implicated was MYBPC3 (63 %). More patients were on optimal medical treatment after following up with our HCM center. Electrocardiographic, Holter, echocardiographic, and cardiac magnetic resonance imaging characteristics differed based on genotype status. The composite outcome was worse in Gen-P than Gen-N (HR 1.84, p<0.001). Although analysis of all-cause mortality showed survival was different for Gen-P and VUS patients than for Gen-N patients, this difference was not statistically significant. MYBPC3 was the most common gene implicated. Outcomes were worse in Gen-P patients. Centers of Excellence play an important role in the optimal medical management of patients with HCM. Show less

This study aims to clinically and genetically assess 30 unrelated consanguineous Pakistani families from various ethnic backgrounds, all exhibiting features of neurodevelopmental disorders (NDDs). We conducted clinical, genetic, biochemical, and molecular analyses on 30 consanguineous families with NDDs enrolled from various regions of Pakistan. The likely molecular causes of primary microcephaly and NDDs were identified. Detailed clinical investigations and molecular diagnoses were performed using whole exome sequencing (WES) of the proband, followed by Sanger sequencing for validation and segregation in the available family members of the affected families. WES identified likely disease-causing homozygous variants in 30 unrelated consanguineous families. Six families presented newly described variants in known NDD-related genes: In the present study, we observed a high frequency of Show less

Encephalitis is a rare and potentially fatal manifestation of herpes simplex type 1 infection. Following genome-wide genetic analyses, we identified a previously uncharacterized and very rare heterozygous variant in the E3 ubiquitin ligase WWP2, in a 14-month-old girl with herpes simplex encephalitis. The p.R841H variant (NM₀₀₇₀₁₄.4:c.2522G > A) impaired TLR3 mediated signaling in inducible pluripotent stem cells-derived neural precursor cells and neurons; cells bearing this mutation were also more susceptible to HSV-1 infection compared to control cells. The p.R841H variant increased TRIF ubiquitination in vitro. Antiviral immunity was rescued following the correction of p.R841H by CRISPR-Cas9 technology. Moreover, the introduction of p.R841H in wild type cells reduced such immunity, suggesting that this mutation is linked to the observed phenotypes. Show less

Alzheimer's disease (AD) is a complex, multifactorial and most prevalent progressive neurodegenerative ailment. Its multifactorial and complex nature causes the lack of disease modifying drugs. Hence, multi-target drug design strategies have been adopted to halt the progression of AD. In current research, we applied multitarget strategy to tackle multifactorial nature of AD. Rational design and synthesis of framework of hybrids containing Pyrimidine/pyrrolidine-sertraline scaffolds were carried out. The synthesized compounds were further evaluated for their in-vitro enzyme inhibition potential against cholinesterases, monoamine oxidases and β-site amyloid precursor protein cleaving enzyme-1 (BACE-1). Compound 19 emerged as an optimal multipotent hybrid with IC Show less

Sudden cardiac death (SCD) in individuals younger than 40 years has a heritable cause in a significant part of the cases. Identification of SCD, post mortem genetic analysis along with the cardiological screening examination in first degree represents an important diagnostic tool for the primary prevention of cardiac arrest in victim´s relatives and requires multicentric and multidisciplinary collaboration. Between 2016 and 2021 the complex cardiogenetic analysis was performed in 115 deaths with post mortem diagnosis of cardiomyopathy, acute aortic dissection and cases without morphological finding explaining the cause of death (sudden arrhythmic death or sudden unexplained death). DNA was isolated from post mortem collected tissue samples or relative´s blood and subjected to massively parallel sequencing (Illumina, USA) in extent of 100 to 20 000 genes. Sequencing results were analysed using the SOPHiA GENETICS DDM bioinformatics platform (Switzerland). Genetic counselling and cardiological examinations were carried out in 328 family members. Highly likely or certain molecular aetiology (i.e. based on presence of ACMG.net Class 4 to 5 variants) was disclosed in 19,8 % of analysed cases in RYR2, KCNH2, KCNQ1, SCN5A, FLNC (stop), GLA, TTN, TNNT2, RBM 20, MYBPC3, MYPN, FHL1, TGFBR1, and COL3A1 genes. With cardiogenetic screening we identified 25 % relatives at risk of life threating arrhythmias and offered them an individualised care. Show less

Congenital malformations of the heart and circulatory system are the most common type of human birth defect. Recent studies have implicated the Notch signaling pathway in human cardiac development by demonstrating abnormalities of the JAG1 gene as the basis for Alagille syndrome and some cases of isolated tetralogy of Fallot or pulmonic stenosis. How the Notch pathway acts in cardiac development remains unknown, but the Hey family of basic helix-loop-helix (bHLH) transcription factors are candidates for mediating Notch signaling in the developing cardiovascular system. Here, we use gene targeting to determine the developmental functions of mouse Hey2, a Hey family member that is expressed during the embryonic development of the heart, arteries, and other organs. Homozygotes for the Hey2 mutant allele display a spectrum of cardiac malformations including ventricular septal defects, tetralogy of Fallot, and tricuspid atresia, defects that resemble those associated with mutations of human JAG1. These results establish Hey2 as an important regulator of cardiac morphogenesis and suggest a role for Hey2 in mediating or modulating Notch signaling in the developing heart. Show less

ANCHORING of ion channels at specific subcellular sites is critical for neuronal signalling, but the mechanisms underlying channel localization and clustering are largely unknown (reviewed in ref. 1). Voltage-gated K+ channels are concentrated in various neuronal domains, including presynaptic terminals, nodes of Ranvier and dendrites, where they regulate local membrane excitability. Here we present functional and biochemical evidence that cell-surface clustering of Shaker-subfamily K+ channels is mediated by the PSD-95 family of membrane-associated putative guanylate kinases, as a result of direct binding of the carboxy-terminal cytoplasmic tails to the K+ channel subunits to two PDZ (also known as GLGF or DHR) domains in the PSD-95 protein. The ability of PDZ domains to function as independent modules for protein-protein interaction, and their presence in other junction-associated molecules (such as ZO-1 (ref. 3) and syntrophin), suggest that PDZ-domain-containing polypeptides may be widely involved in the organization of proteins at sites of membrane specialization. Show less