Search Results (4,033)

Alzheimer’s disease (AD) is increasingly recognized as a multifactorial disorder driven by a combination of disruptions in proteostasis and organelle communication. The 2020 Lancet commission reported that approximately 10 million people worldwide were affected by AD in the mid-20th century. AD is the most prevalent cause of dementia. By early 2030, the global cost of dementia is projected to rise by USD 2 trillion per year, with up to 85% of that cost attributed to daily patient care. Several factors have been implicated in the progression of neurodegeneration, including increased oxidative stress, the accumulation of misfolded proteins, the formation of amyloid plaques and aggregates, the unfolded protein response (UPR), and mitochondrial–endoplasmic reticulum (ER) calcium homeostasis. However, the exact triggers that initiate these pathological processes remain unclear, in part because clinical symptoms often emerge gradually and subtly, complicating early diagnosis. Among the early hallmarks of neurodegeneration, elevated levels of reactive oxygen species (ROS) and the buildup of misfolded proteins are believed to play pivotal roles in disrupting proteostasis, leading to cognitive deficits and neuronal cell death. The accumulation of amyloid-β (Aβ) plaques and tau neurofibrillary tangles is a characteristic feature of AD. These features contribute to chronic neuroinflammation, which is marked by the release of pro-inflammatory cytokines and chemokines that exacerbate oxidative stress. Given these interconnected mechanisms, targeting stress-related signaling pathways, such as oxidative stress (ROS) generated in the mitochondria and ER, ER stress, UPR, and cytosolic chaperones, represents a promising strategy for therapeutic intervention. This review focuses on the relationship between stress chaperone responses and organelle function, particularly the interaction between mitochondria and the ER, in the development of new therapies for AD and related neurodegenerative disorders. Full article

To advance the development of protein-rich plant-based foods, a novel binder system for vegan sausage alternatives without the requirement of heat application was investigated. This enables long-term ripening of plant-based analogs similar to traditional fermented meat or dairy products, allowing for refined flavor and texture development. This was achieved by using a poorly water-soluble calcium source (calcium carbonate) to introduce calcium ions into a low-ester pectin—gluten matrix susceptible to crosslinking via divalent ions. The gelling reaction of pectin–gluten dispersions with Ca²⁺ ions was time-delayed due to the gradual production of lactic acid during fermentation. Firm, sliceable matrices were formed, in which particulate substances such as texturized proteins and solid vegetable fat could be integrated, hence forming an unheated raw-fermented plant-based salami-type sausage model matrix which remained safe for consumption over 21 days of ripening. Gluten as well as pectin had a significant influence on the functional properties of the matrices, especially water holding capacity (increasing with higher pectin or gluten content), hardness (increasing with higher pectin or gluten content), tensile strength (increasing with higher pectin or gluten content) and cohesiveness (decreasing with higher pectin or gluten content). A combination of three simultaneously occurring effects was observed, modulating the properties of the matrices, namely, (a) an increase in gel strength due to increased pectin concentration forming more brittle gels, (b) an increase in gel strength with increasing gluten content forming more elastic gels and (c) interactions of low-ester pectin with the gluten network, with pectin addition causing increased aggregation of gluten, leading to strengthened networks. Full article

In the search for alternative protein sources, single cell proteins have gained increasing attention in recent years. Among them, proteins derived from yeast represent a promising but still underexplored option. To enable their application in food product design, their techno-functional properties must be understood. In order to investigate the impact of precipitation pH on their emulsion-stabilizing properties, yeast proteins from Saccharomyces cerevisiae were isolated via precipitation at different pH (pH 3.5 to 5) after cell disruption in the high-pressure homogenizer. Emulsions containing 5 wt% oil and ~1 wt% protein were analyzed for stability based on their droplet size distribution. Proteins precipitated at pH 3.5 stabilized the smallest oil droplets and prevented partitioning of the emulsion, outperforming proteins precipitated at higher pH values. It is hypothesized that precipitation under acidic conditions induces protein denaturation and thereby exposes hydrophobic regions that enhance adsorption at the oil–water interface and the stabilization of the dispersed oil phase. To investigate the stabilization mechanism, the molecular weight of the proteins was determined using SDS-PAGE, their solubility using Bradford assay, and their aggregation behavior using static laser scattering. Proteins precipitated at pH 3.5 possessed larger molecular weights, lower solubility, and a strong tendency to aggregate. Overall, the findings highlight the potential of yeast-derived proteins as bio-surfactants and suggest that pH-controlled precipitation can tailor their functionality in food formulations. Full article

Protein degradation plays a fundamental role in maintaining protein homeostasis and ensures proper cellular function by regulating protein quality and quantity. Heat shock protein 100 (Hsp100), found in bacteria, plants, and fungi, is a unique chaperone family responsible for rescuing misfolded proteins from aggregated states in an ATP-dependent manner. To date, they are primarily known to mediate heat stress adaptation and enhance cellular survival under extreme conditions in higher plants and algae. Resting cyst formation in dinoflagellates is widely recognized as a response to adverse conditions, which offers an adaptive advantage to endure harsh environmental extremes that are unsuitable for vegetative cell growth and survival. In this study, based on a full-length cDNA sequence, we characterized an Hsp100 gene (SaHsp100) from the cosmopolitan bloom-forming dinoflagellate Scrippsiella acuminata, aiming to examine its life stage-specific expression patterns and preliminarily explore its potential functions. The qPCR results revealed that Hsp100 transcript levels were significantly elevated in newly formed resting cysts compared to vegetative cells and continued to increase during storage under simulated marine sediment conditions (darkness, low temperature, and anoxia). Parallel reaction monitoring (PRM)-based quantification further confirmed that Hsp100 protein levels were significantly higher in resting cysts than in vegetative cells and increased after three months of storage. These findings collectively highlighted the fundamental role of Hsp100 in the alteration of the life cycle and dormancy maintenance of S. acuminata, likely by enhancing stress adaptation and promoting cell survival through participation in proteostasis maintenance, particularly under natural sediment-like conditions that trigger severe abiotic stress. Our work deepens the current understanding of Hsp family members in dinoflagellates, paving the way for future investigations into their ecological relevance within this ecologically significant group. Full article

A novel brain positron emission tomography (PET) radioligand, [¹¹C]HY-2-15, has potential for imaging alpha-synuclein aggregations in multiple system atrophy and misfolded tau proteins in tauopathies, based on its high binding affinity in disease brain tissue homogenates. Here, we demonstrate that [³H]HY-2-15 has the capability to bind to aggregated alpha-synuclein in multiple system atrophy brain and tau aggregations in progressive supranuclear palsy and corticobasal degeneration brain tissues via in vitro autoradiography study. A first-in-human pilot multicenter clinical study recruited a total of 10 subjects including healthy controls and patients with Parkinson’s disease, multiple system atrophy, or progressive supranuclear palsy. The study revealed that [¹¹C]HY-2-15 has a relatively higher specific uptake in the pallidum and midbrain of patients with progressive supranuclear palsy. Total-body scans performed on the PennPET Explorer showed the radiotracer was cleared by renal excretion. However, the rapid metabolism and low brain uptake resulted in a limited signal of [¹¹C]HY-2-15 in brain. Full article

Alpha-Synuclein (α-Syn) is a presynaptic neuronal protein implicated in the pathogenesis of Parkinson’s disease (PD) and other synucleinopathies, primarily through its aggregation into insoluble fibrils. The extended α-Syn half-life necessitates treatment durations that are incompatible with efficient high-throughput drug screening, can risk compound stability or cause cellular toxicity. To address this, we inserted a PEST sequence, a motif known to promote rapid protein degradation, at the C-terminus of the SNCA gene using CRISPR/Cas9 to create a novel cell line with reduced α-Syn half-life. This modification accelerates α-Syn turnover, providing a robust model for studying α-Syn dynamics and offering a platform that is applicable to other long-lived proteins. Our results demonstrate a six-fold reduction in α-Syn half-life, enabling the rapid detection of changes in protein levels and facilitating the identification of molecules that modulate α-Syn production and degradation pathways. Using inhibitors of the proteasome, transcription, and translation further validated the model’s utility in examining various mechanisms that impact protein levels. This novel cell line represents a significant advancement for studying α-Syn dynamics and offers promising avenues to develop therapeutics for α-synucleinopathies. Future research should focus on validating this model in diverse experimental settings and exploring its potential in high-throughput screening applications. Full article

Background/Objectives: Niemann-Pick disease Type C (NPC) represents an autosomal recessive disorder with an incidence rate of 1 in 100,000 live births that belongs to the lysosomal storage diseases (LSDs). NPC is characterized by the abnormal accumulation of unesterified cholesterol, in addition to being an autosomal recessive inherited pathology, which belongs to LSDs. It occurs in 95% of cases due to mutations in the NPC1 gene, while 5% of cases are due to mutations in the NPC2 gene. In the cerebral cortex (CC), the disease shows lipid inclusions, increased cholesterol and multiple sphingolipids in neuronal membranes, and protein aggregates such as hyperphosphorylated tau, α-Synuclein, TDP-43, and β-amyloid peptide. Mitochondrial damage and oxidative stress are some alterations at the cellular level in NPC. Therefore, the aim of this work was to determine the gene expression profile in the CC of NPC1 mice in order to identify altered molecular pathways that may be related to the pathophysiology of the disease. Methods: In this study, we performed a microarray analysis of a 22,000-gene chip from the cerebral cortex of an NPC mutant mouse compared to a WT mouse. Subsequently, we performed a bioinformatic analysis in which we found groups of dysregulated genes, and their expression was corroborated by qPCR. Finally, we performed Western blotting to determine the expression of proteins probably dysregulated. Results: We found groups of dysregulated genes in the cerebral cortex of the NPC mouse involved in the ubiquitination, fatty acid metabolism, differentiation and development, and underexpression in genes with mitochondrial functions, which could be involved in intrinsic apoptosis reported in NPC, in addition, we found a generalized deregulation in the cortical circadian rhythm pathway, which could be related to the depressive behavior that has even been reported in NPC patients. Conclusions: Recognizing that there are changes in the expression of genes related to ubiquitination, mitochondrial functions, and cortical circadian rhythm in the NPC mutant mouse lays the basis for targeting treatments to new potential therapeutic targets. Full article

Vital pulp therapy with calcium hydroxide or mineral trioxide aggregate (MTA) rapidly induces dystrophic calcification and promotes the accumulation of two members of small integrin-binding ligand N-linked glycoproteins: osteopontin (OPN) and dentin matrix protein-1 (DMP1). However, the precise relationship between these initial events and their roles in reparative dentinogenesis remain unclear. This study aimed to clarify the relationship between dystrophic calcification, OPN and DMP1 accumulation, and reparative dentin formation. Pulpotomy was performed on rat molars using MTA or zirconium oxide (ZrO₂). ZrO₂ was used as a control to assess pulp healing in the absence of dystrophic calcification. Pulpal responses were evaluated from 3 h to 7 days postoperatively via elemental mapping, micro-Raman spectroscopy, and histological staining. In the MTA-treated group, a calcium-rich dystrophic calcification zone containing calcite and hydroxyapatite was observed at 3 h after treatment; OPN and DMP1 accumulated under the dystrophic calcification zone by day 3; reparative dentin formed below the region of OPN and DMP1 accumulation by day 7. In contrast, these reactions did not occur in the ZrO₂-treated group. These results suggest that dystrophic calcification serves as a key trigger for OPN and DMP1 accumulation and plays a pivotal role in reparative dentinogenesis. 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

TREM2 (triggering receptor expressed on myeloid cells 2) is a membrane-bound receptor primarily expressed on microglia in the central nervous system (CNS). TREM2 plays a crucial role in regulating immune responses, phagocytosis, lipid metabolism, and inflammation. Mutations in the TREM2 gene have been linked to various neurodegenerative diseases, including Alzheimer’s disease (AD), frontotemporal dementia (FTD), Parkinson’s disease (PD), and Nasu–Hakola disease (NHD). These mutations are suggested to impair microglial activation and reduce the ability to clear amyloid aggregates, leading to exacerbated neuroinflammatory responses and accelerating disease progression. This review provides an overview of TREM2 structure, functions, and known pathogenic variants—including Arg47His, Arg62His, His157Tyr, Tyr38Cys, and Thr66Met. Furthermore, the molecular and cellular consequences of TREM2 mutations are introduced, such as impaired ligand binding, altered protein folding and trafficking, enhanced TREM2 shedding, and dysregulated inflammatory signaling. We also highlight recent advances in therapeutic strategies aimed at modulating TREM2 signaling. These include monoclonal antibodies (e.g., AL002, CGX101), small molecule agonists, and gene/cell-based therapies that seek to restore microglial homeostasis, enhance phagocytosis, and reduce neuroinflammation. While these approaches show promise in in vivo/in vitro studies, their clinical translation may be challenged by disease heterogeneity and mutation-specific responses. Additionally, determining the appropriate timing and precise dosing will be essential. Full article

Candida fungal species are the most common fungal opportunistic pathogens. Their ability to form antifungal resistant biofilms contributes to their increasing clinical frequency. These fungi express surface-anchored adhesins including members of the Als family. These adhesins mediate epithelial adhesion, aggregation, and biofilm formation. Many of the adhesins contain cross-β core sequences that form amyloid-like protein aggregates on the fungal surface. The aggregates mediate high-avidity bonding that contributes to biofilm establishment and persistence. Accordingly, autopsy sections from individuals with candidiasis and other mycoses have amyloids within abscesses. An amyloid-forming peptide containing a sequence from Candida albicans Als5 bound to C. albicans, C. tropicalis, and C. parapsilosis. C. albicans and C. tropicalis aggregated with beads coated with serum albumin, and the aggregates stained with the amyloid-binding dye thioflavin T. Additionally, an Als5-derived amyloid-inhibiting peptide blocked cell aggregation. The amyloid-inhibiting peptide also blocked C. albicans, C. tropicalis, and C. parapsilosis adhesion to monolayers of FaDu epithelial cells. These results show the involvement of amyloid-like interactions in pathogenesis in several Candida species. Full article

The search for substances that increase the immunity of bees is becoming a necessity in the era of various environmental threats and the declining immunocompetence of these insects. Therefore, we tested the biological and physicochemical properties of 7-diethylamino-4-hydroxycoumarin (7DOC). In a cage test, two groups of bees were created: a control group fed with sugar syrup and an experimental group fed with sugar syrup with the addition of 7DOC. In each group, the longevity of the bees was determined and the protein concentrations and antioxidant activities in the bees’ hemolymph were determined. The bees fed with 7DOC lived 2.7 times longer than those in the control group. The protein concentrations and activities of SOD, CAT, GPx and GST, as well as the TAC levels, were significantly higher in the hemolymph of the supplemented workers. To confirm these potent biological properties of 7DOC, the UV-Vis spectra, emission and excitation of fluorescence, synchronous spectra and finally the fluorescence lifetimes of this compound were measured using the time-correlated single photon counting method, in various environments differing in polarity and in the environment applied in bee research. This compound was shown to be sensitive to changes in solvent polarity. The spectroscopic assays were complemented with crystallographic tests of the obtained monocrystals of the aforementioned compounds, which attested to the aggregation effects observed in the spectra measurements for the selected coumarin. The research results confirm that this compound has the potential to be implemented in apiary management, which will be our application goal, but further research into apiary conditions is required. Full article

Background: Coagulation disorders, including both bleeding and thrombotic complications, are common in patients undergoing hemodialysis (HD). Here, we aimed to characterize platelet function in patients undergoing hemodialysis three times per week, compared to healthy controls. Methods: Platelet function was assessed using the Multiplate analyzer (Roche), which is based on multiple electrode impedance aggregometry. Platelet aggregation was induced using adenosine diphosphate (ADP), and the area under the curve (AUC) served as the primary endpoint. In addition, platelet counts and C-reactive protein (CRP) levels were measured. To further evaluate nitric oxide (NO)-mediated inhibition of platelet aggregation, blood samples were incubated with the NO donor, sodium nitroprusside (SNP), and the phosphodiesterase 5A (PDE5A) inhibitor, sildenafil. Results: A total of 60 patients undergoing HD and 67 healthy controls were included in the analysis. Patients receiving HD treatment had significantly lower platelet counts compared to healthy controls (226.9 ± 53.47 vs. 246.7 ± 47.21 G/L, p = 0.029). Platelet aggregation was markedly reduced in patients undergoing HD compared to controls (462.0 ± 266.54 vs. 644.5 ± 254.44 AU × min, p < 0.001) with a significant correlation for platelet count (r = 0.42, p = 0.001) and systemic inflammation as indicated by CRP levels (r = 0.28, p = 0.035). Following SNP and sildenafil administration, inhibition of platelet aggregation remained more pronounced in patients undergoing HD. However, the change in platelet aggregation after SNP/sildenafil treatment did not differ significantly between the groups. Conclusions: Patients undergoing HD exhibit altered platelet function, indicated by reduced aggregation and platelet counts, as well as an association with systemic inflammation. Multiple electrode impedance aggregometry appears to be a feasible method for detecting platelet function alterations in patients receiving HD treatment. Responsiveness to NO donors was preserved in patients undergoing HD. Further studies are needed to identify the underlying mechanisms, particularly the role of NO signaling in platelet dysfunction in patients undergoing HD. Full article

This study investigated quality changes in seaweed–yak patties before and after freeze–thaw by varying seaweed addition levels (10–70%). Macroscopically, the effects on water-holding capacity, textural properties, and oxidative indices of restructured yak patties were evaluated. Microscopically, the impact of seaweed-derived bioactive ingredients on patty microstructure and myofibrillar protein characteristics was examined. LF-NMR and MRI showed that 40% seaweed addition most effectively restricted water migration, reduced thawing loss, and preserved immobilized water content. Texture profile analysis (TPA) revealed that moderate seaweed levels (30–40%) enhanced springiness and minimized post-thaw hardness increases. SEM confirmed that algal polysaccharides formed a denser protective network around the muscle fibers. Lipid oxidation (MDA), free-radical measurements, and non-targeted metabolomics revealed a significant reduction in oxidative damage at 40% seaweed addition, correlating with increased total phenolic content. Protein analyses (particle size, zeta potential, hydrophobicity, and SDS-PAGE) demonstrated a cryoprotective effect of seaweed on myofibrillar proteins, reducing aggregation and denaturation. These findings suggest that approximately 40% seaweed addition can improve the physicochemical stability and antioxidant capacity of frozen seaweed–yak meat products. This work thus identifies the optimal seaweed addition level for enhancing freeze–thaw stability and functional quality, offering practical guidance for the development of healthier, high-value restructured meat products. Full article

Inflammatory bowel disease (IBD) is a chronic gastrointestinal disorder associated with gut microbiota dysbiosis and impaired intestinal barrier function. Probiotic interventions have shown potential in alleviating intestinal inflammation and restoring microbial balance. This study explores the protective effects of Lacticaseibacillus paracasei (L. paracasei) E10 in mice. L. paracasei E10 demonstrated strong gastrointestinal transit tolerance, high mucosal adhesion, and probiotic properties such as hydrophobicity and aggregation ability (p < 0.05). The oral administration of L. paracasei E10 significantly alleviated colitis symptoms by reducing the disease activity index, preserving colonic architecture, increasing goblet cell density, and upregulating tight junction proteins, thereby enhancing intestinal barrier integrity. 16S rRNA sequencing revealed that L. paracasei E10 supplementation enriched microbial diversity, increased the abundance of Muribaculaceae, and modulated the Firmicutes/Bacteroidetes ratio, contributing to gut homeostasis. These findings indicate that L. paracasei E10 is a potential candidate for IBD management. Full article