Search Results (240)

Background/Objectives: Curcumin is a promising therapy for glioblastoma but is limited by poor water solubility, rapid metabolism, and low blood–brain barrier penetration. This study aimed to evaluate curcumin and six curcumin derivatives with improved activity against a glioblastoma cell line and favorable absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties. Methods: Twenty-one curcumin derivatives were assessed and subjected to in vitro MTT cytotoxicity assays in SF268 glioblastoma and Vero cells. On the basis of the cytotoxicity results, six derivatives with the most favorable characteristics were selected for additional mechanistic studies, which included microtubule depolymerization, mitochondrial membrane potential (ΔΨm), and BAX activation assays. ADMET properties were determined in silico. Results: Compounds 2–4, 6, and 11 demonstrated better activity (IC₅₀: 0.59–3.97 µg/mL and SI: 3–20) than curcumin (IC₅₀: 6.3 µg/mL; SI: 2.5). Lead derivatives destabilized microtubules, induced ΔΨm collapse, and activated BAX. In silico ADMET prediction analysis revealed that compounds 4 and 6 were the most promising for oral administration from a biopharmaceutical and pharmacokinetic point of view. Conclusions: Strategic modifications were made to one or both hydroxyl groups of the aromatic rings of curcumin to increase its physicochemical stability and activity against glioblastoma cell line SF268. Compound 4, bearing fully protected aromatic domains, was identified as a prime candidate for in vivo validation and formulation development. Full article

Amyotrophic lateral sclerosis (ALS) remains a progressive neurodegenerative disease, lacking effective causal therapies. The Wobbler mouse model harboring a spontaneous autosomal recessive mutation in the vacuolar protein sorting associated protein (Vps54), has emerged as a valuable model for investigating ALS pathophysiology and potential treatments. This model exhibits cellular and phenotypic parallels to human ALS, including protein aggregation, microglia and astrocyte activation, as well as characteristic disease progression at distinct stages. Exploring the underlying pathomechanisms and identifying therapeutic targets requires a comprehensive analysis of gene and protein expression. In this study, we examined the expression of three well-established housekeeping genes and proteins—calnexin, ß-actin, and ßIII-tubulin—in the cervical spinal cord of the Wobbler model. These candidates were selected based on their demonstrated stability across various systems like animal models or cell culture. Calnexin, an integral protein of the endoplasmic reticulum, ß-actin, a structural component of the cytoskeleton, and ß-tubulin III, a component of microtubules, were quantitatively assessed using quantitative reverse transcription-polymerase chain reaction (RT-PCR) for gene expression and Western blotting for protein expression. Our results revealed no significant differences in the expression of CANX, ACTB, and TUBB3 between spinal cords of wild-type and Wobbler mice at the symptomatic stage (p40) at both the gene and protein levels. These findings suggest that the pathophysiological alterations induced by the Wobbler mutation do not significantly affect the expression of these crucial housekeeping genes and proteins at p40. Overall, this study provides a basis for further investigations using the Wobbler mouse model, while highlighting the potential use of calnexin, ß-actin, and ßIII-tubulin as reliable reference genes and proteins in future research to aid in the discovery for effective therapeutic interventions. Full article

The microtubule-associated protein tau plays an essential role in regulating the dynamic assembly of microtubules and is implicated in axonal elongation and maturation, axonal transport, synaptic plasticity regulation, and genetic stability maintenance. Nevertheless, the assembly of tau into neurofibrillary tangles in neurons is a pathological hallmark of a group of neurodegenerative diseases known as tauopathies. Despite enormous efforts and rapid advancements in the field, effective treatment remains lacking for these diseases. In this review, we provide an overview of the structure and phase transition of tau protein. In particular, we focus on the involvement of liquid–liquid phase separation in the biology and pathology of tau. We then discuss several potential strategies for combating tauopathies in the context of phase separation: (i) modulating the formation of tau condensates, (ii) delaying the liquid-to-solid transition of tau condensates, (iii) reducing the enrichment of aggregation-prone species into tau condensates, and (iv) suppressing abnormal post-translational modifications on tau inside condensates. Deciphering the structure–activity relationship of tau phase transition modulators and uncovering the conformational changes in tau during phase transitions will aid in developing therapeutic agents targeting tau in the context of phase separation. Full article

The efficacy of in vitro fertilization (IVF) is significantly hindered by early embryonic developmental failure and oocyte maturation arrest. Recent findings in reproductive genetics have identified several oocyte-specific genes—TUBB8, KIF11, and CKAP5—as essential regulators of meiotic spindle formation and cytoskeletal dynamics. Mutations in these genes can lead to significant meiotic defects, fertilization failure, and embryo arrest. The links between genotype and phenotype, along with the underlying biological mechanisms, remain inadequately characterized despite the increasing number of identified variations. This systematic review was conducted in accordance with PRISMA 2020 guidelines. Relevant papers were retrieved from the PubMed and Embase databases using combinations of the keywords “TUBB8,” “KIF11,” “CKAP5,” “oocyte maturation arrest,” “embryonic arrest,” and “IVF failure.” Studies were included if they contained clinical, genomic, and functional data on TUBB8, KIF11, or CKAP5 mutations in women undergoing IVF. Molecular data, including gene variant classifications, inheritance models, in vitro tests (such as microtubule network analysis in HeLa cells), and assisted reproductive technology (ART) outcomes, were obtained. Eighteen trials including 35 women with primary infertility were included. Over fifty different variants were identified, the majority of which can be attributed to TUBB8 mutations. TUBB8 disrupted α/β-tubulin heterodimer assembly due to homozygous missense mutations, hence hindering meiotic spindle formation and leading to early embryo fragmentation or the creation of many pronuclei and cleavage failure. KIF11 mutations resulted in spindle disorganization and chromosomal misalignment via disrupting tubulin acetylation and microtubule transport. Mutations in CKAP5 impaired bipolar spindle assembly and microtubule stabilization. In vitro validation studies showed cytoskeletal disturbances, protein instability, and dominant negative effects in transfected animals. Donor egg IVF was the sole effective treatment; however, no viable pregnancies were documented in patients with pathogenic mutations of TUBB8 or KIF11. TUBB8, KIF11, and CKAP5 are essential for safeguarding oocyte meiotic competence and early embryonic development at the molecular level. Genetic differences in these genes disrupt microtubule dynamics and spindle assembly, resulting in various aspects of oocyte maturation and fertilization. Functional validation underscores the necessity of routine genetic screening for women experiencing unresolved IVF failure, as it substantiates their causal role in infertility. Future therapeutic avenues in ART may be enhanced by tailored counseling and innovative rescue methodologies like as gene therapy. Full article

Colorectal cancer remains a leading malignancy. As the aberrant activation of Wnt/β-catenin signaling causes colorectal cancer, Wnt/β-catenin signaling inhibitors are potential candidates for colorectal cancer treatment. Our drug screening platform identified ursolic acid (UA), a triterpenoid with various biological activities, as a potential anticancer drug because it inhibits the T-cell factor (TCF)/β-catenin-mediated transcriptional activity. Here, we discovered that UA inhibited Wnt signaling by reducing the Wnt reporter activity and Wnt target gene expression, leading to a delay in cell cycle progression and the suppression of cell proliferation. Stepwise epistatic analyses suggested that UA functions on β-catenin protein stability in Wnt signaling. Further studies revealed that UA reduced β-catenin protein levels by Western blotting and immunofluorescent staining and induced autophagy by microtubule-associated protein 1 light chain 3 beta (LC3B) punctate staining. The cotreatment with UA and the autophagy inhibitors chloroquine and wortmannin recovered the β-catenin protein levels. Therefore, UA was confirmed to induce β-catenin degradation by the autophagy–lysosomal degradation system through inhibition in the phosphatidylinositol 3-kinase (PI3K)/Ak strain transforming (protein kinase B; AKT)/mammalian target of rapamycin (mTOR) signaling pathway. Our results not only highlight the potential of UA in Wnt-driven colorectal cancer therapy but also provide a workable Wnt signaling termination approach for the treatment of other Wnt-related diseases. Full article

The aggregation of Tau protein into neurofibrillary tangles (NFTs), a hallmark of Alzheimer’s disease (AD), is associated with cognitive decline. Recent studies have revealed that neuronal cytoskeletal instability drives early AD pathogenesis. The physiological interaction between tau and the microtubule (MT) is crucial for maintaining axonal transport and stability. However, aberrant post-translational modifications (PTMs) in the MT binding domain—such as phosphorylation, acetylation and ubiquitination—trigger tau dissociation, causing microtubule collapse, transport deficits, and synaptic dysfunction. MT dysregulation also affects actin/cofilin-mediated dendritic spine destabilization and causes the hyperplasia of the glial intermediate filament, which exacerbates neuroinflammation and synaptic toxicity. This review systematically explores the functions of neuronal cytoskeletons, deciphers the molecular crosstalk between tau pathology and cytoskeletal remodeling, and proposes multi-target therapeutic strategies to restore cytoskeletal homeostasis, thereby providing novel perspectives for precision interventions in AD Full article

Alzheimer’s disease (AD), a predominant neurodegenerative disorder, is clinically characterized by progressive cognitive deterioration and behavioral deficits. An in-depth understanding of the pathogenesis and neuropathology of AD is essential for the development of effective treatments and early diagnosis techniques. The neuropathological signature of AD involves two hallmark lesions: intraneuronal neurofibrillary tangles composed of hyperphosphorylated tau aggregates and extracellular senile plaques containing amyloid-β (Aβ) peptide depositions. Although Aβ-centric research has dominated AD investigations over the past three decades, pharmacological interventions targeting Aβ pathology have failed to demonstrate clinical efficacy. Tau, a microtubule-associated protein predominantly localized to neuronal axons, orchestrates microtubule stabilization and axonal transport through dynamic tubulin interactions under physiological conditions. In AD pathogenesis, however, tau undergoes pathogenic post-translational modifications (PTMs), encompassing hyperphosphorylation, lysine acetylation, methylation, ubiquitination, and glycosylation. These PTM-driven alterations induce microtubule network disintegration, mitochondrial dysfunction, synaptic impairment, and neuroinflammatory cascades, ultimately culminating in irreversible neurodegeneration and progressive cognitive decline. This review synthesizes contemporary advances in tau PTM research and delineates their mechanistic contributions to AD pathogenesis, thereby establishing a framework for biomarker discovery, targeted therapeutic development, and precision medicine approaches in tauopathies. This review synthesizes contemporary advances in tau PTM research and delineates their mechanistic contributions to AD pathogenesis, thereby establishing a solid theoretical and experimental basis for the early diagnosis of neurodegenerative diseases, the discovery of therapeutic targets, and the development of novel therapeutic strategies. Full article

Axon guidance, a fundamental process in neural circuit formation, is intricately regulated by Fibroblast Growth Factors (FGFs) and their receptors (FGFRs) through dynamic cytoskeletal remodeling. FGF signaling, mediated by heparan sulfate proteoglycans or Klotho co-factors, activates key downstream pathways: PI3K-Akt, JAK-STAT, PLCγ, and RAS-MAPK. These pathways orchestrate actin filament dynamics, microtubule stability, and the organization of intermediate filaments. These pathways converge on Rho GTPases, cofilin, profilin, and tau to balance the cytoskeletal assembly−disassembly cycles, enabling growth cone navigation. Unresolved questions, such as the mechanisms underlying FGF-mediated growth cone steering, highlight critical future research directions. This review integrates structural, molecular, and functional insights into how FGF-FGFR interactions regulate axon pathfinding, emphasizing the crosstalk between signaling cascades and cytoskeletal plasticity. Elucidating these mechanisms not only advances our understanding of neural development but also opens therapeutic avenues for neuro-developmental disorders, nerve injury, and neurodegenerative diseases by targeting FGF-driven cytoskeletal dynamics. Full article

Tau protein plays a pivotal role in maintaining neuronal structure and function through its regulation of microtubule stability and neuronal polarity. Encoded by the MAPT gene, Tau exists in multiple isoforms due to alternative mRNA splicing, with differential expression in the central and peripheral nervous systems. In healthy neurons, tau mRNA is selectively localized and translated in axons, a process tightly regulated by untranslated regions (UTRs) and RNA-binding proteins such as HuD and FMRP. Pathologically, Tau undergoes hyperphosphorylation, misfolding, and aggregation, which contribute to neurodegeneration in a range of disorders collectively known as tauopathies. Alzheimer’s disease (AD) is the most prevalent tauopathy, where abnormal Tau accumulation in the temporal and frontal lobes correlates with cognitive decline and behavioral symptoms. Other tauopathies, including Progressive Supranuclear Palsy (PSP), Corticobasal Degeneration (CBD), Frontotemporal Dementia with Parkinsonism (FTDP-17), and Pick’s disease, are distinguished by the predominance of specific Tau isoforms (3R or 4R), cellular distribution, and affected brain regions. Notably, astroglial tauopathies highlight the pathological role of Tau accumulation in glial cells, expanding the understanding of neurodegeneration beyond neurons. Despite advances in imaging biomarkers (e.g., Tau-PET) and molecular diagnostics, effective disease-modifying therapies for tauopathies remain elusive. Ongoing research targets Tau through immunotherapies, splicing modulators, kinase inhibitors, and antisense oligonucleotides, aiming to mitigate Tau pathology and its deleterious effects. Understanding the multifaceted roles of Tau in neuronal and glial contexts is critical for developing future therapeutic strategies against tauopathies. Full article

The genus Taxus comprises a unique group of gymnosperms known for their botanical longevity, cultural significance, and exceptional pharmacological potential. This review explores the multifaceted profile of Taxus species, with a focus on their morphological traits, phytochemical composition, traditional uses, and therapeutic applications. Particular attention is given to taxanes, especially paclitaxel, which have revolutionized cancer treatment through microtubule-stabilizing mechanisms. In addition to well-established uses of the bark and leaves, the review synthesizes emerging research on the aril, a non-toxic and antioxidant-rich plant part, suggesting novel biomedical applications. By integrating ethnobotanical knowledge with contemporary pharmacological insights, this work underscores the enduring relevance of Taxus in traditional medicine while emphasizing its evolving role in modern drug discovery. The findings advocate for intensified interdisciplinary research and sustainable exploitation strategies to fully harness the genus’s therapeutic potential without compromising biodiversity. Full article

Background/Objectives: Cannabigerol (CBG) is a non-psychoactive phytocannabinoid with significant therapeutic potential, showing emerging applications in drug delivery. This study aimed to develop and evaluate CBG-conjugated nanoparticles (NPs) incorporating tubulin-targeting drugs to enhance anticancer activity. Methods: CBG was conjugated with N-desacetylthiocolchicine, paclitaxel, and camptothecin using sebacic acid and 4,4′-dithiodibutyric acid as linkers, and nanoparticles were obtained. The NPs were characterized by their stability and size (hydrodynamic diameters < 90 nm). Their antiproliferative activity was assessed in three human tumor cell lines and non-tumorigenic cells. Their cellular uptake and mechanisms of action were investigated via confocal microscopy and cell cycle analysis. Results: The chemical composition of the linkers significantly influenced the antiproliferative effect, with the NPs containing 4,4′-dithiodibutyric acid demonstrating higher activity. Notably, NP3b, formulated with this linker, exhibited up to an 80-fold increase in antiproliferative potency compared to its sebacic acid counterpart (NP3a). In mesothelioma cells (MSTO-211H), NP3b displayed significantly higher cytotoxicity than in non-tumorigenic mesothelial cells (MeT-5A), indicating selectivity for cancer cells. Further analysis in glioblastoma cells confirmed that the NPs retained the microtubule-disrupting effects of their parent drugs. Conclusions: These findings highlight the potential of CBG-based NPs as versatile nanomedicine platforms for targeted cancer therapy. This study underscores the importance of linker chemistry in modulating therapeutic efficacy and supports the development of multifunctional drug delivery systems. Full article

Cardiovascular diseases are the leading cause of morbidity and mortality worldwide, underscoring the urgent need for novel therapeutic targets and strategies. The kinase MARK4 (MAP (microtubule-associated proteins)/microtubule affinity-regulating kinase 4) regulates microtubule-associated proteins pivotal for cell polarity, protein stability, and intracellular signaling. Animal models of heart failure revealed elevated MARK4 levels, which correlated with impaired cardiac contractility. However, the involvement of MARK4 and its potential as a molecular drug target has not yet been explored in the myocardium of cardiovascular patients. We investigated the MARK4 mRNA expression in human myocardial biopsies of 152 high-risk cardiovascular patients undergoing cardiac surgery. Comprehensive echocardiography as well as testing for sleep-disordered breathing (SDB), a critical comorbidity in heart failure, were assessed preoperatively. We observed a substantial upregulation of myocardial MARK4 expression in patients with impaired cardiac contractility, resulting in an inverse correlation with the left ventricular ejection fraction. Myocardial MARK4 expression also correlated with echocardiographic E/e’, a central parameter of diastolic dysfunction. Mechanistically, our analyses revealed that MARK4 expression increases in SDB and under hypoxic conditions, as evidenced by significant correlations between myocardial MARK4 expression and factors like mean oxygen saturation, time with oxygen saturation below 90%, and the oxygen desaturation index. Multivariable regression analysis revealed that both left ventricular ejection fraction and mean oxygen saturation were independently associated with dysregulated MARK4 levels, even when controlling for important clinical covariables as potential confounders. Taken together, our findings demonstrate that MARK4 expression is highly increased in the myocardium of cardiovascular high-risk patients, suggesting it is a potential molecular target against cardiovascular diseases. Full article

Poor embryo quality is a major cause of poor clinical outcomes in assisted reproductive medicine, and there are no currently available interventions that can improve embryo quality. Mitochondria dysfunction is linked to low-quality female gametes and zygotes. Previously, microtubule integrity was also associated with mitochondrial function in oocytes. In the present study, we investigated the effects of the microtubule stabilizers (MTS) Taxol and Epothilone D (EpD) and the microtubule disturber (MTD) vinorelbine on mouse preimplantation embryo quality and pregnancy outcome compared with non-treatment controls. We prepared young BDF1 mice (7~9 weeks old) and cultured preimplantation embryos with MTS or MTD. Mitochondrial functional activity and embryo development ratios including pregnancy ratios were then assessed. MTS-treated embryos showed significantly increased mitochondrial membrane potentials and motility. Blastocyst formation was significantly higher in MTS-treated embryos than in MTD-treated embryos. Especially, MTS-treated embryos exhibited higher hatched blastocyte formation than untreated embryos. The number of offspring was significantly higher in surrogate mice transplanted with MTS-treated embryos. These findings demonstrated that the treatment of mouse preimplantation embryos with Taxol or EpD increased embryo development competence, which was associated with increased mitochondrial functional activity. Consistently, delivery ratios were significantly higher after transplantation with MTS-treated embryos than after transplantation with untreated embryos. These findings suggest that MTS could be used to supplement in vitro culture media to promote the recovery of poor-quality embryos. Full article

The inner ear and/or lateral line are responsible for hearing and balance of vertebrate. The otic sensory hair cells (HCs) employ cilium organelles, namely stereocilia and/or kinocilia, to mediate mechanical stimuli to electrical signal transition. Tektins (Tekts) are known as the cilium microtubule stabilizer and inner-space filler, and four Tekt(1-4)-encoding genes are identified in zebrafish HCs, but the subcellular location of Tekts in HCs remains unknown. In the present study, we first found that tekt3 is expressed in the inner ear and lateral line neuromast. Antibody staining revealed that Tekt3 is present in neuromast and utricular HCs. It is absent in the saccule, the authentic hearing end-organ of zebrafish and the crista of semi-circular canals. Furthermore, Tekt3 were enriched at the apical side of neuromast and utricular HCs, mainly in the cytosol. Similar subcellular distribution of Tekt3 was also evident in the outer HCs of mature mouse cochlea, which are not directly linked to the hearing sense. However, only neuromast HCs exerted morphological defect of kinocilia in tekt3 mutant. The disrupted or distorted HC kinocilia of mutant neuromast ultimately resulted in slower vital dye intake, delayed HC regeneration after neomycin treatment, and reduced startle response to vibration stimulation. All functional defects of tekt3 mutant were largely rescued by wild-type tekt3 mRNA. Our study thus suggests that zebrafish Tekt3 maintains the integrity and function of neuromast kinocilia to against surrounding and persistent low-frequency noises, perhaps via the intracellular distribution of Tekt3. Nevertheless, TEKT3/Tekt3 could be used to clarify HC sub-types in both zebrafish and mice, to highlight the non-hearing HCs. Full article

Background: Acetylation of α-tubulin is an important post-translational modification that helps maintain microtubules’ stability and dynamics, including axonal transport, cell signaling, and overall neuronal integrity. This study investigates sex-based differences in alcohol-induced acetylation of α-tubulin in mouse cerebellum. Methods: Adult, 3-month-old male and female C57BL/6 mice were administered 20% ethanol intraperitoneally. The cerebellum was dissected at 30 min, 1 h, 2 h, and 4 h post-injection. Expression levels of cerebellar acetylation of α-tubulin and enzymes mediating acetylation/deacetylation were analyzed by Western blot. The downstream product of ethanol metabolism, acetyl-CoA, was quantified by HPLC. Results: In males, α-tubulin acetylation levels increased significantly as early as 30 min post-ethanol injection, whereas females exhibited increased acetylation at a later time point, after 1 h. These sex-specific changes coincided with alterations in acetyl-CoA levels that increased significantly at 15 min in males and 1 h in females following ethanol administration. Furthermore, the level of acetyltransferase that acetylates tubulin increased significantly at 30 min in males and 1 h in females. Notably, however, no significant changes were observed in the level of the tubulin deacetylating enzyme, HDAC6, in either sex. Conclusions: Our data demonstrate that these sex differences stem from variations in expression levels of tubulin acetyltransferase (αTAT1), and the rate of ethanol metabolism-related acetyl-CoA production between male and female animals. Full article