Search Results (7,245)

Chronic infection with the hepatitis B virus (HBV) results in over 1 million deaths annually. Although currently licensed treatments, including pegylated interferon-α and nucleoside/nucleotide analogs, can inhibit viral replication, they rarely eradicate covalently closed circular DNA (cccDNA) reservoirs. Moreover, vaccination does not offer therapeutic benefit to already infected individuals or non-responders. Consequently, chronic infection is maintained by the persistence of cccDNA in infected hepatocytes. For this reason, novel therapeutic strategies that permanently inactivate cccDNA are a priority. Obligate heterodimeric transcription activator-like effector nucleases (TALENs) provide the precise gene-editing needed to disable cccDNA. To develop this strategy using a therapeutically relevant approach, TALEN-encoding mRNA targeting viral core and surface genes was synthesized using in vitro transcription with co-transcriptional capping. TALENs reduced hepatitis B surface antigen (HBsAg) by 80% in a liver-derived mammalian cell culture model of infection. In a stringent HBV transgenic murine model, a single dose of hepatotropic lipid nanoparticle-encapsulated TALEN mRNA lowered HBsAg by 63% and reduced viral particle equivalents by more than 99%, without evidence of toxicity. A surveyor assay demonstrated mean in vivo HBV DNA mutation rates of approximately 16% and 15% for Core and Surface TALENs, respectively. This study presents the first evidence of the therapeutic potential of TALEN-encoding mRNA to inactivate HBV replication permanently. Full article

Lactoferrin (LF) is an 80 kDa iron-binding glycoprotein primarily found in milk, saliva, tears, and nasal secretions. LF is well known for its antibacterial and immunomodulatory effects. However, the extraction of LF from milk is inadequate for large-scale therapeutic applications, presenting a challenge for economic mass production. Recombinant protein expression systems offer a solution to overcome this challenge and efficient production of LF. This review discusses recent progress in the translational research of LF gene transfer and biopharming, focusing on different expression systems such as bacteria, yeast, filamentous fungi, transgenic crops, and animals as well as purification methods. The optimization of expression yields, prospects for genetic engineering, and biotechnology to enhance LF production for biomedical applications are emphasized. This review systematically sourced the literature from 1987 to 2025 from leading scientific databases, including PubMed, Scopus, Web of Science, and Google Scholar. Despite ongoing debates, progress in this field indicates a viable path towards the effective use of LF in therapeutic settings. Full article

Macrophages are undoubtedly one of the most widely studied cells of the immune system, among other reasons, because they are involved in a wide variety of biological processes. Deregulation of their activity is observed in a number of different disorders, including autoimmune diseases. At the same time, mammalian target of rapamycin (mTOR) is attracting increasing research attention because the pathways dependent on this kinase are activated by a variety of signals, including cytokines and proinflammatory mediators, mediate essential processes for cell survival and metabolism, and can be regulated epigenetically via microRNAs. Therefore, our narrative review aimed to summarize and discuss recent advances in the knowledge of the activation of mTOR signaling in macrophages, with a special focus on autoimmune disorders and the possibility of mTOR control by microRNAs. The summarized research observations allowed us to conclude that the effects of activity and/or inhibition of individual mTOR complexes in macrophages are largely context dependent, and therefore, these broad immunological contexts and other specific conditions should always be taken into account when attempting to modulate these pathways for therapeutic purposes. Full article

Plant-derived vesicles offer several advantages, including high yield, low cost, ethical compatibility, safety, and potential health benefits. These advantages enable them to overcome technological limitations associated with vesicles of mammalian origin. Ginseng, a prominent example of a natural botanical plant, is known for its abundant bioactive components. Recent studies confirmed that ginseng-derived vesicles offer significant advantages in the treatment of human diseases. Therefore, this study reviews the extraction and purification processes of ginseng-derived vesicle-like nanoparticles (GDVLNs), their therapeutic potential, and the active ingredients in GDVLNs that may exert pharmacological activities. Furthermore, this study evaluates the research and applications of nanosized ginseng extracts, with a primary focus on ginsenosides. Full article

Cardiovascular disease encompasses a wide group of conditions that affect the heart and blood vessels. Of these diseases, cardiomyopathies and arrhythmias specifically have been well-studied in their relationship to cardiac dyads, nanoscopic structures that connect electrical signals to muscle contraction. The proper development and positioning of dyads is essential in excitation–contraction (EC) coupling and, thus, beating of the heart. Three proteins, namely CMYA5, JPH2, and BIN1, are responsible for maintaining the dyadic cleft between the T-tubule and junctional sarcoplasmic reticulum (jSR). Various other dyadic proteins play integral roles in the primary function of the dyad—translating a propagating action potential (AP) into a myocardial contraction. Ca²⁺, a secondary messenger in this process, acts as an allosteric activator of the sarcomere, and its cytoplasmic concentration is regulated by the dyad. Loss-of-function mutations have been shown to result in cardiomyopathies and arrhythmias. Adeno-associated virus (AAV) gene therapy with dyad components can rescue dyadic dysfunction, which results in cardiomyopathies and arrhythmias. Overall, the dyad and its components serve as essential mediators of calcium homeostasis and excitation–contraction coupling in the mammalian heart and, when dysfunctional, result in significant cardiac dysfunction, arrhythmias, morbidity, and mortality. Full article

The rabies virus (RABV) phosphoprotein (P protein) has multiple functions, including acting as the essential non-catalytic cofactor of the viral polymerase (L protein) for genome replication and transcription; the principal viral antagonist of the interferon (IFN)-mediated innate immune response; and the chaperone for the viral nucleoprotein (N protein). Although P protein is known to undergo phosphorylation by cellular kinases, the location and functions of the phosphorylation sites remains poorly defined. Here, we report the identification by mass-spectrometry (MS) of residues of P protein that are modified by phosphorylation in mammalian cells, including several novel sites. Analysis of P protein with phospho-mimetic and phospho-inhibitory mutations of three novel residues/clusters that were commonly identified by MS (Ser48, Ser183/187, Ser217/219/220) indicate that phosphorylation at each of these sites does not have a major influence on nuclear trafficking or antagonistic functions toward IFN signalling pathways. However, phosphorylation of Ser48 in the N-terminus of P protein impaired function in transcription/replication and in the formation of replication structures that contain complexes of P and N proteins, suggestive of altered interactions of these proteins. The crystal structure of P protein containing the S48E phospho-mimetic mutation indicates that Ser48 phosphorylation facilitates the binding of residues 41–52 of P protein into the RNA-binding groove of non-RNA-bound N protein (N⁰), primarily through the formation of a salt bridge with Arg434 of N protein. These data indicate that Ser48 modification regulates the cycling of P-N⁰ chaperone complexes that deliver N protein to RNA to enable transcription/replication, such that enhanced interaction due to S48E phospho-mimetic mutation reduces N protein delivery to the RNA, inhibiting subsequent transcription/replication processes. These data are, to our knowledge, the first to implicate phosphorylation of RABV P protein in conserved replication functions of the P gene. Full article

Background: Previous research has demonstrated that 20 kHz probe or 37 kHz bath sonication of poloxamers comprising polypropylene glycol (PPG) and polyethylene glycol (PEG) blocks can generate degradation byproducts that are toxic to mammalian cells and organisms. Herein, an investigation of a PEGylated phospholipid micelle was undertaken to identify low-molecular-weight sonolytic degradation byproducts that could be cytotoxic. The concern here lies with the fact that sonication is a frequently employed step in drug delivery manufacturing processes, during which PEGylated phospholipids can be subjected to shear forces and other extreme oxidative and thermal conditions. Methods: Control and 20 kHz-sonicated micelles of DSPE-mPEG2000 were analyzed using dynamic light scattering (DLS) and zeta potential analyses to study colloidal properties, matrix-assisted laser desorption/ionization–time of flight (MALDI-TOF) mass spectroscopy (MS) and proton nuclear magnetic resonance (¹H-NMR) spectroscopy to study the structural integrity of DSPE-mPEG2000, and ¹H-NMR spectroscopy and high-performance liquid chromatography (HPLC) with ultraviolet (UV) detection to quantitate the formation of low-molecular-weight degradation byproducts. Results: MALDI-TOF-MS analyses of 20 kHz-sonicated DSPE-mPEG2000 revealed the loss of ethylene glycol moieties in accordance with depolymerization of the PEG chain; ¹H-NMR spectroscopy showed the presence of formate, a known oxidative/thermal degradation product of PEG; and HPLC-UV showed that the generation of formate was dependent on 20 kHz probe sonication time between 5 and 60 min. Conclusions: It was found that 20 kHz sonication can degrade the PEG chain of DSPE-mPEG2000, altering the micelle’s PEG corona and generating formate, a known ocular toxicant. Full article

Stress granule formation is a type of liquid–liquid phase separation in the cytoplasm, leading to RNA–protein condensates that are associated with various cellular stress responses and implicated in numerous pathologies, including cancer, neurodegeneration, inflammation, and cellular senescence. One of the key components of mammalian stress granules is the DEAD-box RNA helicase DDX3, which unwinds RNA in an ATP-dependent manner. DDX3 is involved in multiple steps of RNA metabolism, facilitating gene transcription, splicing, and nuclear export and regulating cytoplasmic translation. In this study, we investigate the role of the RNA helicase DDX3’s enzymatic activity in shaping the RNA content of ribonucleoprotein (RNP) condensates formed during arsenite-induced stress by inhibiting DDX3 activity with RK-33, a small molecule previously shown to be effective in cancer clinical studies. Using the human osteosarcoma U2OS cell line, we purified the RNP granule fraction and performed RNA sequencing to assess changes in the RNA pool. Our results reveal that RK-33 treatment alters the composition of non-coding RNAs within the RNP granule fraction. We observed a DDX3-dependent increase in circular RNA (circRNA) content and alterations in the granule-associated intronic RNAs, suggesting a novel role for DDX3 in regulating the cytoplasmic redistribution of non-coding RNAs. Full article

The presence of nest boxes not only increases the reproductive success of many passerine birds in transformed forest habitats, but they also constitute important artificial microhabitats for many groups of invertebrates. One of such groups which have been often found in this microhabitat is saprophagous mites from the suborder Uropodina (Acari: Mesostigmata). The current study was conducted in October 2023 and 2024 in Bory Tucholskie National Park (BTNP) (northern Poland), where material from 137 tit (Paridae) and nuthatch (Sitta europaea) nest boxes was collected. The aim of this study was to analyse the stability of the communities of Uropodina in nest boxes in the park in two seasons and to determine whether the mite community structure within these nest boxes is similar in each year. The second aim was to analyse the abundance of Uropodina in relation to the composition of the nest box bedding material. This study revealed that the community in the scrutinised nest boxes was formed in both seasons by two species of nidicolous Uropodina species, i.e., Leiodinychus orbicularis (C.L. Koch, 1839) and Chiropturopoda nidiphila (Wiśniewski and Hirschmann, 1993), and that the species composition and the community structure were also very similar in both years. This study revealed that Ch. nidiphila dominated in the nest boxes with moss and grass, whereas L. orbicularis was most abundant in the boxes where the bedding was a mixture of mammalian hair and grass. However, no statistically significant differences in the abundance of these two mite species in both cases were revealed. Full article

A method for configuration synthesis of a reconfigurable decoupled parallel mechanical leg is proposed. In addition, a configuration evaluation index is proposed to evaluate the synthesized configurations and select the optimal one. Kinematic analysis and performance optimization of the selected mechanism’s configuration are carried out, and the motion mode of the robot’s reconfigurable mechanical leg is selected according to the task requirements. Then, the robot’s gait in walking mode is planned. Firstly, based on bionic principles, the motion characteristics of a mechanical leg based on a mammalian model and an insect model were analyzed. The input and output characteristics of the mechanism were analyzed to obtain the reconfiguration principle of the mechanism. Using type synthesis theory for the decoupled parallel mechanism, the configuration synthesis of the chain was carried out, and the constraint mode of the mechanical leg was determined according to the constraint property of the chain and the motion characteristics of the moving platform. Secondly, an evaluation index for the complexity of the reconfigurable mechanical leg structure was developed, and the synthesized mechanism was further analyzed and evaluated to select the mechanical leg’s configuration. Thirdly, the inverse position equations were established for the mechanical leg in the two motion modes, and its Jacobian matrix was derived. The degrees of freedom of the mechanism are completely decoupled in the two motion modes. Then, the workspace and motion/force transmission performance of the mechanical leg in the two motion modes were analyzed. Based on the weighted standard deviation of the motion/force transmission performance, the global performance fluctuation index of the mechanical leg motion/force transmission is defined, and the structural size parameters of the mechanical leg are optimized with the performance index as the optimization objective function. Finally, with the reconfigurable mechanical leg in the insect mode, the robot’s gait in the walking operation mode is planned according to the static stability criterion. Full article

Glucose is the main source of energy and the source of carbon for the biosynthesis of several molecules, such as neurotransmitters, for most mammalian cells. Therefore, the transport of glucose into cells is very important. There are described three distinct families of glucose transporters: facilitative glucose transporters (GLUTs), sodium-dependent glucose cotransporters (SGLTs), and a uniporter, the SWEET protein. Impaired function and/or expression of these transporters due to, for example, mutations in their genes, may cause severe diseases. Associations with the impaired function of glucose transporters have been described in the case of neurodegenerative diseases (NDs) such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, GLUT1-deficiency syndrome, stroke, and traumatic brain injury. Changes in the presence of glucose transporters may be a cause of NDs, and they may be the effect of NDs. On the other hand, in many cases of neurodegenerative diseases, changes in the expression of glucose transporters may be a targeted therapy in the treatment of patients with these diseases. Full article

Miller–Dieker Syndrome (MDS) is a rare neurodevelopmental disorder caused by a heterozygous deletion of approximately 26 genes within the MDS locus of human chromosome 17. MDS, which affects 1 in 100,000 babies, can lead to a range of phenotypes, including lissencephaly, severe neurological defects, distinctive facial abnormalities, cognitive impairments, seizures, growth retardation, and congenital heart and liver abnormalities. One hallmark feature of MDS is an unusually smooth brain surface due to abnormal neuronal migration during early brain development. Several genes located within the MDS locus have been implicated in the pathogenesis of MDS, including PAFAH1B1, YWHAE, CRK, and METTL16. These genes play a role in the molecular and cellular pathways that are vital for neuronal migration, the proper development of the cerebral cortex, and protein translation in MDS. Improved model systems, such as MDS patient-derived organoids and multi-omics analyses indicate that WNT/β-catenin signaling, calcium signaling, S-adenosyl methionine (SAM) homeostasis, mammalian target of rapamycin (mTOR) signaling, Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling, and others are dysfunctional in MDS. This review of MDS integrates details at the clinical level alongside newly emerging details at the molecular and cellular levels, which may inform the development of novel therapeutic strategies for MDS. Full article

Ant venoms are rich sources of bioactive molecules, including peptide toxins with potent and selective activity on ion channels, which makes them valuable for pharmacological research and therapeutic development. Voltage-dependent potassium (Kv) channels, critical for regulating cellular excitability or cell cycle progression control, are targeted by a diverse array of venom-derived peptides. This study focuses on MYRTX_A4-Tb11a, a peptide from Tetramorium bicarinatum venom, which was previously shown to have a strong paralytic effect on dipteran species without cytotoxicity on insect cells. In the present study, we show that Tb11a exhibited no or low cytotoxicity toward mammalian cells either, even at high concentrations, while electrophysiological studies revealed a blockade of hKv1.3 activity. Additionally, Ta11a, an analog of Tb11a from the ant Tetramorium africanum, demonstrated similar Kv1.3 inhibitory properties. Structural analysis supports that the peptide acts on Kv1.3 channels through the functional dyad Y21-K25 and that the disulfide bridge is essential for biological activity, as reduction seems to disrupt the peptide conformation and impair the dyad. These findings highlight the importance of three-dimensional structure in channel modulation and establish Tb11a and Ta11a as promising Kv1.3 inhibitors. Future research should investigate their selectivity across additional ion channels and employ structure-function studies to further enhance their pharmacological potential. Full article

Cyclic nucleotide signaling pathways play essential roles in the physiology of the nematode Caenorhabditis elegans, influencing processes such as reproduction, environmental sensing, and cellular homeostasis. The intracellular levels of cAMP and cGMP are tightly regulated by their synthesis by adenylyl and guanylyl cyclases and their degradation catalyzed by 3′,5′-cyclic nucleotide phosphodiesterases (PDEs). Mammals possess eleven PDE families (PDE1 through PDE11), whereas nematode genomes contain six PDE genes orthologous to six of the mammalian PDE families. Despite their evolutionary conservation, the signaling pathways, regulatory mechanisms, and enzymatic properties of nematode PDEs remain incompletely understood. This review synthesizes current knowledge on the regulation of cyclic nucleotide levels in C. elegans, highlighting how dysregulation of nematode PDEs affects a wide range of physiological and behavioral processes, including sensory transduction, development, and locomotion. Full article

MOTS-c is a mitochondrial peptide that plays a crucial role in regulating energy metabolism, gene expression, and immune processes. However, current research primarily focuses on mammals like humans and mice, with no reports on avian MOTS-c. This study aimed to identify and characterize MOTS-c coding sequences across major poultry species through bioinformatics analysis and experimental validation. The alignment results showed high sequence similarity in the MOTS-c coding regions between avian and mammalian species. However, a single nucleotide deletion was identified in avian sequences at the position corresponding to the fourth amino acid residue of mammalian homologs, resulting in divergent downstream amino acid sequences. Despite this deletion, several residues were conserved across species. Phylogenetic analysis of mRNA sequences grouped pigeons with mammals, while protein sequence analysis revealed that poultry and mammals form separate branches, highlighting the divergence between avian and mammalian MOTS-c sequences. Tissue expression profiling demonstrated widespread distribution of chicken MOTS-c across multiple tissues, with the highest expression levels in the heart. Fasting significantly reduced heart MOTS-c expression, suggesting potential metabolic regulatory functions. Functional analysis of MOTS-c in primary hepatocytes revealed significant enrichment of the ribosome, oxidative phosphorylation, and key signaling pathways (PI3K-AKT and JAK-STAT) following 24 hours of treatment. Western blot validation confirmed MOTS-c-mediated activation of the AKT signaling pathway. This study represents the first comprehensive characterization of avian MOTS-c, providing critical insights into its evolutionary conservation and its potential functional roles in gene expression and cellular metabolism. Our findings establish a foundation for further investigation into the functions of mitochondrial-encoded peptides in avian species. Full article