Search Results (141)

Mitochondria serve as an essential component in the maintenance of cardiac function, and targeting them may represent a promising approach to handling heart failure (HF). HF in this review refers to various etiologies, including ischemic cardiomyopathy, dilated cardiomyopathy, and hypertrophic cardiomyopathy, unless otherwise specified. Mitochondrial dysfunction, a distinctive feature of HF, leads to a progressive decrease in bioenergetic reserves due to switching of energy production from oxidation of fatty acids in mitochondria to glycolytic pathways. The main problem in developing methods to improve mitochondrial function lies in the fact that protein preparations injected through the bloodstream cannot enter cells through the plasma membrane. Modern gene therapy involving the delivery of missing genes to cells using adeno-associated virus (AAV) vectors has the potential to improve the function of cardiomyocytes (CMCs). This type of therapy aims to target proteins that have been lost, damaged, or altered due to pathological conditions in the myocardium. This review summarizes pathophysiological mechanisms associated with mitochondrial dysfunction, which is mainly caused by increased oxidative stress and impaired mitochondrial biodynamics under HF progression. It also addresses possible ways to modulate these processes using gene therapy. Special attention is paid to modern characteristics of AAVs that can be used as vectors for the efficient delivery of desired genes to CMCs. Full article

Testosterone (T) produced by Leydig cells (LCs) is essential for male reproduction; yet, the regulatory mechanisms underlying steroidogenesis remain incompletely understood. Here, we investigated the role of cyclin-dependent kinase 5 regulatory subunit-associated protein 3 (CDK5RAP3) in Leydig cell development and steroidogenesis, based on its identification by immunoprecipitation-mass spectrometry (IP-MS) as a protein associated with steroidogenesis and cholesterol metabolism in mouse testicular tissue. Using human samples, we found that CDK5RAP3 expression was significantly reduced in Leydig cells from patients with spermatogenic failure (T < 10.4 nmol/L). Notably, CDK5RAP3 expression increased during mouse postnatal Leydig cell maturation and regeneration in an ethane dimethanesulfonate (EDS)-induced rat model. Functional analyses in primary LCs and MLTC-1 cells showed that hCG stimulation triggered CDK5RAP3 nuclear translocation without altering its overall expression, while CDK5RAP3 knockdown markedly impaired hCG-induced testosterone production and reduced the expression of the steroidogenic regulator steroidogenic acute regulatory (STAR) protein, as well as key steroidgenic enzymes, including cytochrome P450 family 11 subfamily A member 1 (CYP11A1), 17a-hydroxylase (CYP17A1), and 3β-hydroxysteroid dehydrogenase (HSD3B). Conversely, CDK5RAP3 overexpression enhanced testosterone production in the absence of hCG. In vivo, AAV2/9-mediated CDK5RAP3 silencing in adult mouse testes resulted in a significant reduction in serum testosterone levels compared with controls (3.60 ± 0.38 ng/mL vs. 1.83 ± 0.37 ng/mL). Mechanistically, CDK5RAP3 interacted with SMAD4 and CEBPB, and BMP pathway inhibition by Noggin rescued the testosterone deficit caused by CDK5RAP3 loss. Together, these findings identify CDK5RAP3 as an essential regulator of Leydig cell steroidogenesis and provide insight into its potential relevance to male infertility associated with low testosterone. Full article

The stable and safe integration of exogenous DNA into the genome is crucial to both genetic engineering and gene therapy. Traditional transgenesis approaches, such as those using retroviral vectors, result in random genomic integration, posing the risk of insertional mutagenesis and transcriptional dysregulation. Safe harbor sites (SHSs), genomic loci that support reliable transgene expression without compromising endogenous gene function, genomic integrity, or cellular physiology, have been identified and characterized across various model organisms. Well-established SHSs such as AAVS1, ROSA26, and CLYBL are routinely utilized for targeted transgene integration in human cells. Recent advances in genome architecture, gene regulation, and genome editing technologies are driving the discovery of novel SHSs for precise and safe genetic modification. This review aims to provide a comprehensive overview of SHSs and their applications that will guide investigators in the choice of SHS, especially when complementary sites are needed for more than one transgene integration. First, it outlines safety and functional criteria that qualify a genomic site as a safe harbor site. It then discusses the two primary strategies for identifying SHSs: i) traditional lentiviral-based random transgenesis, and ii) modern genome-wide in silico screening followed by CRISPR-based validation. This review also provides an updated catalogue of currently known SHSs in the human genome, detailing their characteristics, uses, and limitations. Additionally, it discusses the diverse applications of SHSs in basic research, gene therapy, CAR T cell-based therapy, and biotechnological production systems. Finally, it concludes by highlighting challenges in identifying universally applicable SHSs and outlines future directions for their refinement and validation across biological systems. Full article

Skeletal muscle atrophy underlies sarcopenia, frailty, and muscular dystrophies, but the molecular mechanisms linking oxidative stress to muscle degeneration remain incompletely understood. We previously identified protein complex formation between transient receptor potential canonical 3 (TRPC3) and NADPH oxidase 2 (Nox2) as a key driver of anthracycline-induced myocardial atrophy. Here, we investigated whether this complex also contributes to skeletal muscle wasting. In skeletal muscle from sciatic nerve transection model mice and Duchenne muscular dystrophy (mdx) mice, TRPC3-Nox2 complex formation was enhanced. TRPC3 deletion significantly attenuated denervation-induced soleus atrophy and reduced reactive oxygen species (ROS) production. TRPC3-Nox2 complex formation was upregulated in the soleus muscle (SM) of mdx mice. Pharmacological disruption of the TRPC3-Nox2 interaction improved muscle size and strength and reduced plasma creatine kinase in mdx mice. A recombinant adeno-associated virus (AAV) encoding a TRPC3 C-terminal peptide was used to suppress TRPC3-Nox2 complex formation in vivo. AAV-mediated expression of TRPC3 C-terminal peptide mitigated muscle wasting (CSA) in mdx mice, while muscle strength and plasma CK were not significantly improved. Thus, TRPC3-Nox2 complex formation may be a pivotal driver of oxidative stress-mediated skeletal muscle atrophy. Targeting this protein–protein interaction represents a promising therapeutic strategy for Duchenne muscular dystrophy (DMD) and other intractable muscle-wasting disorders. Full article

Duchenne muscular dystrophy (DMD) is a severe X-linked hereditary disorder caused by pathogenic variants in the DMD gene encoding the dystrophin protein. The absence of functional dystrophin leads to destabilization of the dystrophin-associated glycoprotein complex (DAPC), sarcolemmal damage, and progressive degeneration of muscle fibers. Current therapeutic strategies focus on restoring dystrophin expression using genome editing approaches. Adeno-associated virus (AAV) vectors represent the primary delivery platform due to their strong tropism for muscle tissue, low immunogenicity, and ability to achieve long-term transgene expression. However, the limited packaging capacity of AAV (~4.7 kb) necessitates the use of truncated mini- and micro-dystrophin transgenes as well as compact genome editing systems (SaCas9, NmeCas9, Cas12f, TIGR-Tas, and others). Major challenges include immune responses against the viral capsid and transgene products, as well as the inability to perform repeated administrations. Moreover, the duration of expression is limited by the episomal nature of AAV genomes and their loss during muscle fiber regeneration. Despite substantial progress, unresolved issues concerning safety, immunogenicity, and stability of genetic correction remain, defining the key directions for future research in DMD therapy. Full article

Hemophilia B is a hereditary bleeding disorder caused by mutations localized throughout the F9 gene. Existing gene therapy products containing AAV vectors have significant limitations. Replacement therapy with coagulation factor FIX infusions is not an optimal way of treatment, as patients still have periodic bleeding and require frequent transfusions. Moreover, approximately 5% of adult patients with hemophilia B develop inhibitory antibodies to recombinant forms of FIX. Therefore, it is important to develop universal CRISPR/Cas gene therapy approaches for F9 editing using non-viral delivery systems to enable gene reversion to a functional sequence at an early stage of disease development and establishment of the patients’ immune system. In this study, a unique approach of F9 prime-editing was tested for the first time. This method is estimated to edit 7.3% of pathogenic F9 mutation types. Specifically, it targets the gene region encoding amino acids 374 V to 408 Q, which accounts for approximately 9.35% of patients with hemophilia B. An advantage of this gene therapy approach is the absence of the need to change Primer Binding Site (PBS) or Reverse Transcriptase Template (RTT) sequences until going from preclinical to clinical trials, as well as the introduction of gain of function mutations in order to compensate for the low prime-editing frequencies and enhance the effect of treatment in vivo. Full article

Hemophilia, an X-linked recessive bleeding disorder, results from mutations in the F8 or F9 genes, leading to factor VIII (hemophilia A) or factor IX (hemophilia B) deficiency. While conventional treatment relies on regular factor replacement therapy, gene therapy has emerged as a promising alternative, offering the potential for sustained endogenous factor production after a single administration. This review provides an in-depth analysis of recent advances in gene therapy for both hemophilia A and B, with a focus on AAV-mediated liver-directed approaches and other approved modalities. Key limitations—such as vector immunogenicity, hepatic toxicity, waning transgene expression, and limited re-dosing capacity—are discussed. Additional gene delivery platforms, including lentiviral and retroviral vectors, genome editing techniques (e.g., CRISPR/Cas9), and non-viral systems like transposons and lipid nanoparticles, are also examined. Although gene therapy for hemophilia B demonstrates greater clinical durability, hemophilia A presents unique challenges due to factor VIII’s size, poor expression efficiency, and the need for higher vector doses. Future efforts will focus on overcoming immune barriers, improving delivery technologies, and developing approaches suitable for pediatric patients and individuals with pre-existing immunity. This review provides not only a descriptive overview but also a critical comparison of gene therapy approaches for hemophilia A and B. We emphasize that the durability of response is currently superior in hemophilia B, whereas hemophilia A still faces unique barriers, including declining FVIII expression and higher immunogenicity. By analyzing cross-platform challenges (AAV, lentiviral, CRISPR, and emerging LNPs), we highlight the most promising strategies for overcoming these limitations and provide a forward-looking perspective on the future of gene therapy. Full article

Currently, the development of adeno-associated virus (AAV)-based gene therapy is a promising method for treating various diseases and is gaining increasing popularity. However, the use of AAV has certain drawbacks and faces limitations such as immune responses and an increased risk of insertional mutagenesis, which have not always been adequately considered in the context of AAV therapy. Moreover, a significant limitation for the application of AAV lies in the challenge of producing it in large quantities. This article discusses the use of AAV in treating various diseases, reviews AAV production approaches, highlights challenges with insufficient viral titers during production, and explores potential solutions at key stages of AAV drug production. Full article

Skeletal muscle, constituting ~40% of body mass, serves as a primary effector for movement and a key metabolic regulator through myokine secretion. Hereditary myopathies, including dystrophinopathies (DMD/BMD), limb–girdle muscular dystrophies (LGMD), and metabolic disorders like Pompe disease, arise from pathogenic mutations in structural, metabolic, or ion channel genes, leading to progressive weakness and multi-organ dysfunction. Gene therapy has emerged as a transformative strategy, leveraging viral and non-viral vectors to deliver therapeutic nucleic acids. Adeno-associated virus (AAV) vectors dominate clinical applications due to their efficient transduction of post-mitotic myofibers and sustained transgene expression. Innovations in AAV engineering, such as capsid modification (chemical conjugation, rational design, directed evolution), self-complementary genomes, and tissue-specific promoters (e.g., MHCK7), enhance muscle tropism while mitigating immunogenicity and off-target effects. Non-viral vectors (liposomes, polymers, exosomes) offer advantages in cargo capacity (delivering full-length dystrophin), biocompatibility, and scalable production but face challenges in transduction efficiency and endosomal escape. Clinically, AAV-based therapies (e.g., Elevidys^® for DMD, Zolgensma^® for SMA) demonstrate functional improvements, though immune responses and hepatotoxicity remain concerns. Future directions focus on AI-driven vector design, hybrid systems (AAV–exosomes), and standardized manufacturing to achieve “single-dose, lifelong cure” paradigms for muscular disorders. Full article

We recently reported that phospholipase A2 (PLA2)-mediated production of prostaglandins within the ventromedial hypothalamus (VMH) plays a critical role in systemic glucose homeostasis. However, the role of PLA2 in the VMH in regulating food intake is still unclear. Here, we attempted to investigate the role of PLA2 in regulating food intake and body weight in male mice. We injected an adeno-associated virus encoding short hairpin RNA (AAV-shRNA) targeting cytosolic phospholipase A2 (shPla2g4a) into the VMH. We assessed food intake, body weight, oxygen consumption, glucose tolerance, and insulin sensitivity. Three weeks after the AAV injection, the shPla2g4a group exhibited increased food intake and body weight gain compared to controls (shSCRM). Energy expenditure, oxygen consumption, and respiratory quotient (RQ) were comparable between groups. Our findings suggest that the cPLA2-mediated pathway in the VMH is critical for feeding behavior and maintaining energy homeostasis. Further investigation is needed to elucidate the underlying mechanisms. Full article

Background and objective. Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) affects small- to medium-sized vessels and is characterized by the production of ANCAs. The ANCA-negative term is used if the patient otherwise fulfills the definition for AAV but has negative results on serologic testing for ANCAs. The objective of this study was to compare ANCA-positive and -negative vasculitis patients and to evaluate the main differences possibly related to the presence of ANCAs. Material and methods. A cross-sectional study of 73 patients treated at the tertiary Rheumatology Centre of University Hospital from the 1 January, 2001, to the 31August, 2023, with diagnoses of AAV was carried out. Clinical characteristics and laboratory data were collected at the onset or at the first year of the disease. Results. Forty-eight (65.8%) patients were ANCA-positive, while twenty-five (34.3%) were ANCA-negative. Distribution by gender was similar in both groups, with a female–male ratio of 2:1. C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were elevated for all AAV patients, but values were higher in the ANCA-positive patients’ group. The median hemoglobin was 106 g/L in the seropositive group and 127 g/L in the seronegative group. A higher prevalence of kidney involvement (60.4%) with elevated serum creatinine level (93.5 µmol/L) was observed in the ANCA-positive group compared with 24% and 70 µmol/l in the ANCA-negative group (p < 0.05). Neurological involvement was more frequently found in the ANCA-positive patient group, too: 29.2% compared to 20%. Among patients with ANCA-negative vasculitis, 88% had pulmonary; 92% ear, nose, throat (ENT); 48% joint; and 28% skin presentation. In comparison, involvement of these organs was less common in the ANCA-positive patients’ group, at 79.2%, 60.4%, 31.3%, and 25 %, respectively. Conclusions. ANCA-positive patients appear to be in a more difficult clinical situation in terms of organ involvement and laboratory changes. Full article

Heart failure (HF) has become an epidemic, with a prevalence of ~7 million cases in the USA. Despite accounting for nearly 50% of all HF cases, heart failure with a preserved ejection fraction (HFpEF) remains challenging to treat. Common pathophysiological mechanisms in HFpEF include oxidative stress, microvascular dysfunction, and chronic unresolved inflammation. Our lab focuses on oxidative stress-mediated cellular dysfunction, particularly the toxic effects of lipid peroxidation products like 4-hydroxy-2-nonenal (4HNE). Aldehyde dehydrogenase 2 (ALDH2), a mitochondrial enzyme, plays a vital role in detoxifying 4HNE and thereby protecting the heart against pathological stress. ALDH2 activity is reduced in various metabolic stress-mediated cardiac pathologies. The dysfunction of coronary vascular endothelial cells (CVECs) is critical in initiating HFpEF development. Thus, we hypothesized that ectopic overexpression of ALDH2 in CVECs could mitigate metabolic stress-induced HFpEF pathogenesis. In this study, we tested the efficacy of intracardiac injections of the ALDH2 gene into CVECs in db/db mice—a model of obesity-induced type 2 diabetes mellitus (T2DM)—and their controls, db/m mice, by injection with ALDH2 constructs (AAV9-VE-cadherin-hALDH2-HA tag-P2A) or control constructs (AAV9-VE-cadherin-HA tag-P2A-eGFP). We found that intracardiac ALDH2 gene transfer increased ALDH2 levels specifically in CVECs compared to other myocardial cells. Additionally, we observed increased ALDH2 levels and activity, along with decreased 4HNE adducts, in the hearts of mice receiving ALDH2 gene transfer compared to control GFP transfer. Furthermore, ALDH2 gene transfer to CVECs improved diastolic function compared to GFP control alone. In conclusion, ectopic ALDH2 expression in CVECs can contribute, at least partially, to the amelioration of HFpEF. Full article

Recombinant adeno-associated virus (rAAV) is the leading vector for gene replacement therapy; however, the roles and regulation of host proteins in rAAV production remain incompletely understood. In this comparative proteomic analysis, we focused on proteins in the nucleus, the epicenter of DNA uptake, transcription, capsid assembly, and packaging. HEK-293 cells were analyzed under the following three conditions: (i) untransfected, (ii) mock-transfected with the ITR and an unrelated plasmid, and (iii) triple-transfected with rAAV2 production plasmids. Cells were harvested at 24 and 72 h post-transfection, and nuclear fractions were processed using filter-aided sample preparation (FASP) followed by nano-scale liquid chromatography–tandem mass spectrometry (nLC-Orbitrap MS/MS). Across all samples, we identified 3384 proteins, revealing significant regulatory changes associated with transfection and rAAV production. Transfection alone accounted for some of the most substantial proteomic shifts, while rAAV production induced diverse regulatory changes linked to cell cycle control, structure, and metabolism. STRING analysis of significantly regulated proteins also identified an enrichment of those associated with the Gene Ontology (GO) term ‘response to virus’. Additionally, we examined proteins with reported relation to adenoviral components. Our findings help to unravel the complexity of rAAV production, identify interesting targets for further investigation, and may contribute to improving rAAV yield. Full article

Neutralizing antibodies (nAbs) are an important component of the immune system, which plays a dual role in modern medicine. On the one hand, they significantly limit the effectiveness of gene therapy based on viral vectors, reducing the effectiveness of treatment of diseases such as spinal muscular atrophy, which is especially evident with repeated administration of therapeutic vectors. On the other hand, nAbs is a promising tool for combating viral infections. This review systematizes current data on the mechanisms of nAbs formation against AAV vectors, analyzes the factors influencing their production, and discusses strategies to overcome this limitation, including modification of vectors and the development of methods to suppress the immune response. Special attention is paid to the prospects of using nAbs as therapeutic agents against viral infections. The key problems and possible directions of research development in this area are considered, which is important for improving approaches to the treatment of both rare genetic and infectious diseases. Full article

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a group of rare but potentially life-threatening autoimmune diseases that affect small to medium-sized blood vessels. Recent evidence highlights the critical role of neutrophil extracellular traps (NETs) in the pathophysiology of AAV. NETs, which are web-like structures composed of DNA and antimicrobial proteins, contribute to vascular damage and immune activation. In patients with AAV, excessive or impaired clearance of NETs can trigger autoantibody production and exacerbate inflammation. This literature review demonstrates the association between NETs and disease activity in AAV. Biomarkers such as MPO-DNA complexes and circulating free DNA can be used to assess disease activity and the response to treatment. Understanding NETosis in the clinical context could improve risk stratification, guide treatment decisions, enable the development of new targeted therapies, and support the development of more precise monitoring tools for AAV treatment. Full article