Stress granules: Guardians of cellular health and triggers of disease

Stress granules are membraneless organelles that serve as a protective cellular response to external stressors by sequestering non-translating messenger RNAs (mRNAs) and regulating protein synthesis. Stress granules formation mechanism is conserved across species, from yeast to mammals, and they play a critical role in minimizing cellular damage during stress. Composed of heterogeneous ribonucleoprotein complexes, stress granules are enriched not only in mRNAs but also in noncoding RNAs and various proteins, including translation initiation factors and RNA-binding proteins. Genetic mutations affecting stress granule assembly and disassembly can lead to abnormal stress granule accumulation, contributing to the progression of several diseases. Recent research indicates that stress granule dynamics are pivotal in determining their physiological and pathological functions, with acute stress granule formation offering protection and chronic stress granule accumulation being detrimental. This review focuses on the multifaceted roles of stress granules under diverse physiological conditions, such as regulation of mRNA transport, mRNA translation, apoptosis, germ cell development, phase separation processes that govern stress granule formation, and their emerging implications in pathophysiological scenarios, such as viral infections, cancer, neurodevelopmental disorders, neurodegeneration, and neuronal trauma.

Recent advances in immunotherapy targeting amyloid-beta and tauopathies in Alzheimer's disease

Alzheimer's disease, a devastating neurodegenerative disorder, is characterized by progressive cognitive decline, primarily due to amyloid-beta protein deposition and tau protein phosphorylation. Effectively reducing the cytotoxicity of amyloid-beta42 aggregates and tau oligomers may help slow the progression of Alzheimer's disease. Conventional drugs, such as donepezil, can only alleviate symptoms and are not able to prevent the underlying pathological processes or cognitive decline. Currently, active and passive immunotherapies targeting amyloid-beta and tau have shown some efficacy in mice with asymptomatic Alzheimer's disease and other transgenic animal models, attracting considerable attention. However, the clinical application of these immunotherapies demonstrated only limited efficacy before the discovery of lecanemab and donanemab. This review first discusses the advancements in the pathogenesis of Alzheimer's disease and active and passive immunotherapies targeting amyloid-beta and tau proteins. Furthermore, it reviews the advantages and disadvantages of various immunotherapies and considers their future prospects. Although some antibodies have shown promise in patients with mild Alzheimer's disease, substantial clinical data are still lacking to validate their effectiveness in individuals with moderate Alzheimer's disease.

Neuronal plasticity and its role in Alzheimer's disease and Parkinson's disease

Neuronal plasticity, the brain's ability to adapt structurally and functionally, is essential for learning, memory, and recovery from injuries. In neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease, this plasticity is disrupted, leading to cognitive and motor deficits. This review explores the mechanisms of neuronal plasticity and its effect on Alzheimer's disease and Parkinson's disease. Alzheimer's disease features amyloid-beta plaques and tau tangles that impair synaptic function, while Parkinson's disease involves the loss of dopaminergic neurons affecting motor control. Enhancing neuronal plasticity offers therapeutic potential for these diseases. A systematic literature review was conducted using databases such as PubMed, Scopus, and Google Scholar, focusing on studies of neuronal plasticity in Alzheimer's disease and Parkinson's disease. Data synthesis identified key themes such as synaptic mechanisms, neurogenesis, and therapeutic strategies, linking molecular insights to clinical applications. Results highlight that targeting synaptic plasticity mechanisms, such as long-term potentiation and long-term depression, shows promise. Neurotrophic factors, advanced imaging techniques, and molecular tools (e.g., clustered regularly interspaced short palindromic repeats and optogenetics) are crucial in understanding and enhancing plasticity. Current therapies, including dopamine replacement, deep brain stimulation, and lifestyle interventions, demonstrate the potential to alleviate symptoms and improve outcomes. In conclusion, enhancing neuronal plasticity through targeted therapies holds significant promise for treating neurodegenerative diseases. Future research should integrate multidisciplinary approaches to fully harness the therapeutic potential of neuronal plasticity in Alzheimer's disease and Parkinson's disease.

Long noncoding RNA GAS5 acts as a competitive endogenous RNA to regulate GSK-3β and PTEN expression by sponging miR-23b-3p in Alzheimer's disease

JOURNAL/nrgr/04.03/01300535-202601000-00042/figure1/v/2025-06-09T151831Z/r/image-tiff Long noncoding RNA and microRNA are regulatory noncoding RNAs that are implicated in Alzheimer's disease, but the role of long noncoding RNA-associated competitive endogenous RNA has not been fully elucidated. The long noncoding RNA growth arrest-specific 5 (GAS5) is a member of the 5'-terminal oligopyrimidine gene family that may be involved in neurological disorders, but its role in Alzheimer's disease remains unclear. This study aimed to investigate the function of GAS5 and construct a GAS5-associated competitive endogenous RNA network comprising potential targets. RNA sequencing results showed that GAS5 was upregulated in five familial Alzheimer's disease (5×FAD) mice, APPswe/PSEN1dE9 (APP/PS1) mice, Alzheimer's disease-related APPswe cells, and serum from patients with Alzheimer's disease. Functional experiments with targeted overexpression and silencing demonstrated that GAS5 played a role in cognitive dysfunction and multiple Alzheimer's disease-associated pathologies, including tau hyperphosphorylation, amyloid-beta accumulation, and neuronal apoptosis. Mechanistic studies indicated that GAS5 acted as an endogenous sponge by competing for microRNA-23b-3p (miR-23b-3p) binding to regulate its targets glycogen synthase kinase 3beta (GSK-3β) and phosphatase and tensin homologue deleted on chromosome 10 (PTEN) expression in an Argonaute 2-induced RNA silencing complex (RISC)-dependent manner. GAS5 inhibited miR-23b-3p-mediated GSK-3β and PTEN cascades with a feedforward PTEN/protein kinase B (Akt)/GSK-3β linkage. Furthermore, recovery of GAS5/miR-23b-3p/GSK-3β/PTEN pathways relieved Alzheimer's disease-like symptoms in vivo , indicated by the amelioration of spatial cognition, neuronal degeneration, amyloid-beta load, and tau phosphorylation. Together, these findings suggest that GAS5 promotes Alzheimer's disease pathogenesis. This study establishes the functional convergence of the GAS5/miR-23b-3p/GSK-3β/PTEN pathway on multiple pathologies, suggesting a candidate therapeutic target in Alzheimer's disease.

Biomaterial-based strategies: a new era in spinal cord injury treatment

Enhancing neurological recovery and improving the prognosis of spinal cord injury have gained research attention recently. Spinal cord injury is associated with a complex molecular and cellular microenvironment. This complexity has prompted researchers to elucidate the underlying pathophysiological mechanisms and changes and to identify effective treatment strategies. Traditional approaches for spinal cord injury repair include surgery, oral or intravenous medications, and administration of neurotrophic factors; however, the efficacy of these approaches remains inconclusive, and serious adverse reactions continue to be a concern. With advancements in tissue engineering and regenerative medicine, emerging strategies for spinal cord injury repair now involve nanoparticle-based nanodelivery systems, scaffolds, and functional recovery techniques that incorporate biomaterials, bioengineering, stem cell, and growth factors as well as three-dimensional bioprinting. Ideal biomaterial scaffolds should not only provide structural support for neuron migration, adhesion, proliferation, and differentiation but also mimic the mechanical properties of natural spinal cord tissue. Additionally, these scaffolds should facilitate axon growth and neurogenesis by offering adjustable topography and a range of physical and biochemical cues. The three-dimensionally interconnected porous structure and appropriate physicochemical properties enabled by three-dimensional biomimetic printing technology can maximize the potential of biomaterials used for treating spinal cord injury. Therefore, correct selection and application of scaffolds, coupled with successful clinical translation, represent promising clinical objectives to enhance the treatment efficacy for and prognosis of spinal cord injury. This review elucidates the key mechanisms underlying the occurrence of spinal cord injury and regeneration post-injury, including neuroinflammation, oxidative stress, axon regeneration, and angiogenesis. This review also briefly discusses the critical role of nanodelivery systems used for repair and regeneration of injured spinal cord, highlighting the influence of nanoparticles and the factors that affect delivery efficiency. Finally, this review highlights tissue engineering strategies and the application of biomaterial scaffolds for the treatment of spinal cord injury. It discusses various types of scaffolds, their integrations with stem cells or growth factors, and approaches for optimization of scaffold design.

External stimuli-responsive drug delivery to the posterior segment of the eye

Posterior segment eye diseases represent the leading causes of vision impairment and blindness globally. Current therapies still have notable drawbacks, including the need for frequent invasive injections and the associated risks of severe ocular complications. Recently, the utility of external stimuli, such as light, ultrasound, magnetic field, and electric field, has been noted as a promising strategy to enhance drug delivery to the posterior segment of the eye. In this review, we briefly summarize the main physiological barriers against ocular drug delivery, focusing primarily on the recent advancements that utilize external stimuli to improve treatment outcomes for posterior segment eye diseases. The advantages of these external stimuli-responsive drug delivery strategies are discussed, with illustrative examples highlighting improved tissue penetration, enhanced control over drug release, and targeted drug delivery to ocular lesions through minimally invasive routes. Finally, we discuss the challenges and future perspectives in the translational research of external stimuli-responsive drug delivery platforms, aiming to bridge existing gaps toward clinical use.

A stacking classifier for distinguishing stages of Alzheimer's disease from a subnetwork perspective

Accurately distinguishing stages of Alzheimer's disease (AD) is crucial for diagnosis and treatment. In this paper, we introduce a stacking classifier method that combines six single classifiers into a stacking classifier. Using brain network models and network metrics, we employ t-tests to identify abnormal brain regions, from which we construct a subnetwork and extract its features to form the training dataset. Our method is then applied to the ADNI (Alzheimer's Disease Neuroimaging Initiative) datasets, categorizing the stages into four categories: Alzheimer's disease, mild cognitive impairment (MCI), mixed Alzheimer's mild cognitive impairment (ADMCI), and healthy controls (HCs). We investigate four classification groups: AD-HCs, AD-MCI, HCs-ADMCI, and HCs-MCI. Finally, we compare the classification accuracy between a single classifier and our stacking classifier, demonstrating superior accuracy with our stacking classifier from a subnetwork-based viewpoint.

R, Khoza. S, Dube A. Vitamin D3 loaded polycaprolactone nanoparticles enhance the expression of the antimicrobial peptide cathelicidin in macrophages

Tuberculosis (TB), primarily caused by Mycobacterium tuberculosis, remains a global health burden. Current antibiotic treatments are limited by adverse effects, poor adherence, and drug resistance, necessitating new therapeutic approaches. Recent studies highlight the role of vitamin D3 (VD3) in enhancing host immune responses against the mycobacterium via cathelicidin (an antimicrobial peptide) and autophagy activation. In this study, VD3-loaded poly-ƹ-caprolactone (PCL) nanoparticles (NPs) were synthesized to enhance cathelicidin expression in macrophages. NPs containing cholecalciferol, calcifediol, and calcitriol were synthesized using an emulsification solvent-evaporation technique. Average sizes of synthesized NPs ranged from 304.7 to 458.7 nm, with polydispersity index (PDI) and zeta potential (ZP) ranging from 0.103 to 0.257 and -17.3 to -7.47 mV, respectively. Encapsulation efficiencies were 9.68%, 10.99%, and 19.28% for cholecalciferol, calcifediol, and calcitriol, respectively. VD3-encapsulated NPs stimulated a dose-dependent increase in cathelicidin expression in THP-1 macrophages. Encapsulated calcifediol and calcitriol (100 ng/ml) induced the expression of 243.46 ng/ml ± 4.55 ng/ml and 396.67 ng/ml ± 25.24 ng/ml of cathelicidin, respectively, which was significantly higher than that induced by the free drugs. These findings suggest that NP encapsulation may offer a more efficient approach to using vitamin D3 for inducing cathelicidin expression as a host-directed treatment for TB.

Antimicrobial capping agents on silver nanoparticles made via green method using natural products from banana plant waste

Herein, we investigated the phytochemical composition and antibacterial activities of the organic layers from biosynthesized silver nanoparticles (AgNPs). AgNPs were synthesized using Musa paradisiaca and Musa sapientum extracts. UV-vis absorption in the 400-450 nm range indicated surface plasmonic resonance peak of AgNPs. Samples analyses using dynamic light scattering and transmission electron microscopy revealed the presence of particles within nanometric ranges, with sizes of 30-140 nm and 8-40 nm, respectively. Fourier transform infrared (FTIR) unveiled the presence of several organic functional groups on the surface of AgNPs, indicating the presence of phytochemicals from plant extracts. Thin layer chromatography (TLC) of the phytochemicals (capping agents) from AgNPs identified multiple groups of secondary metabolites. These phytochemical capping agents exhibited antibacterial activities against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, with minimum inhibitory concentrations ranging from 62.5 to 1000 µg/mL. Regardless of the bacterial species or plant parts (leaves or pseudo-stems), capping agents from M. sapientum nanoparticles displayed significantly enhanced antibacterial effectiveness compared to all other samples, including the raw plant extracts and biosynthesized capped and uncapped AgNPs. These results suggest the presence of antimicrobial phytochemicals on biosynthesized AgNPs, highlighting the promise of green nanoparticle synthesis as a valuable approach in bioprospecting antimicrobial agents.

Harnessing nanofibers for targeted delivery of phytoconstituents in age-related macular degeneration

Age-related macular degeneration is a degenerative eye condition that affects the macula and results in central vision loss. Phytoconstituents show great promise in the treatment of AMD. AMD therapy can benefit from the advantages of phytoconstituents loaded nanofibers. There are opportunities to improve the effectiveness of phytoconstituents in the treatment of age-related macular degeneration (AMD) through the use of nanofiber-based delivery methods. These novel platforms encapsulate and distribute plant-derived bioactives by making use of the special qualities of nanofibers. These qualities include their high surface area-to-volume ratio, variable porosity, and biocompatibility. Exploring the use of nanofiber-based delivery methods to provide phytoconstituents in AMD treatment is a great choice for enhancing patient adherence, safety, and efficacy in managing this condition. This article explores the potential of nanofiber-based delivery methods to revolutionize AMD treatment, providing an innovative and effective approach to treat this condition.

Staphylococcus warneri dampens SUMOylation and promotes intestinal inflammation

Gut bacteria play key roles in intestinal physiology, via the secretion of diversified bacterial effectors. Many of these effectors remodel the host proteome, either by altering transcription or by regulating protein post-translational modifications. SUMOylation, a ubiquitin-like post-translational modification playing key roles in intestinal physiology, is a target of gut bacteria. Mutualistic gut bacteria can promote SUMOylation, via the production of short- or branched-chain fatty acids (SCFA/BCFA). In contrast, several pathogenic bacteria were shown to dampen SUMOylation in order to promote infection. Here, we demonstrate that Staphylococcus warneri, a natural member of the human gut microbiota, decreases SUMOylation in intestinal cells. We identify that Warnericin RK, a hemolytic toxin secreted by S. warneri, targets key components of the host SUMOylation machinery, leading to the loss of SUMO-conjugated proteins. We further demonstrate that Warnericin RK promotes inflammation in intestinal and immune cells using both SUMO-dependent and SUMO-independent mechanisms. We finally show that Warnericin RK regulates the expression of genes involved in intestinal tight junctions. Together, these results highlight the diversity of mechanisms used by bacteria from the gut microbiota to manipulate host SUMOylation. They further highlight that changes in gut microbiota composition may impact intestinal inflammation, by altering the equilibrium between bacterial effectors promoting or dampening SUMOylation.

Proteins of the SubB family provide multiple mechanisms of serum resistance in Yersinia pestis

The serum complement system is a cornerstone element of the innate immune response. Bacterial resistance to this system is a multifaceted process involving various proteins and molecular mechanisms. Here, we report several genes required for the growth of Yersinia pestis in serum. Among them, we found that ypo0337 encodes an outer-membrane-associated lectin that recruits factor H, C4BP and hemopexin, conferring resistance to the serum complement system. YPO0337 displays high sequence similarity with the SubB subunit of the AB5 toxin from Escherichia coli, as well as other SubB-like proteins, and subB from E. coli restores the ability of Y. pestis Δypo0337 mutant to resist to serum complement. Altogether, the data suggest that at least two members of the SubB protein family function as virulence factors, conferring resistance to serum complement through a unique mode of action.

Human tendon stem/progenitor cell-derived extracellular vesicle production promoted by dynamic culture

Tendon injuries significantly impact quality of life, prompting the exploration of innovative solutions beyond conventional surgery. Extracellular Vesicles (EVs) have emerged as a promising strategy to enhance tendon regeneration. In this study, human Tendon Stem/Progenitor Cells (TSPCs) were isolated from surgical biopsies and cultured in a Growth-Differentiation Factor-5-supplemented medium to promote tenogenic differentiation under static and dynamic conditions using a custom-made perfusion bioreactor. Once at 80% confluence, cells were transitioned to a serum-free medium for conditioned media collection. Ultracentrifugation revealed the presence of vesicles with a 106 particles/mL concentration and sub-200nm diameter size. Dynamic culture yielded a 3-fold increase in EV protein content compared to static culture, as confirmed by Western-blot analysis. Differences in surface marker expression were also shown by flow cytometric analysis. Data suggest that we efficiently developed a protocol for extracting EVs from human TSPCs, particularly under dynamic conditions. This approach enhances EV protein content, offering potential therapeutic benefits for tendon regeneration. However, further research is needed to fully understand the role of EVs in tendon regeneration.

Interkingdom signaling between gastrointestinal hormones and the gut microbiome

The interplay between the gut microbiota and gastrointestinal hormones plays a pivotal role in the health of the host and the development of diseases. As a vital component of the intestinal microecosystem, the gut microbiota influences the synthesis and release of many gastrointestinal hormones through mechanisms such as modulating the intestinal environment, producing metabolites, impacting mucosal barriers, generating immune and inflammatory responses, and releasing neurotransmitters. Conversely, gastrointestinal hormones exert feedback regulation on the gut microbiota by modulating the intestinal environment, nutrient absorption and utilization, and the bacterial biological behavior and composition. The distributions of the gut microbiota and gastrointestinal hormones are anatomically intertwined, and close interactions between the gut microbiota and gastrointestinal hormones are crucial for maintaining gastrointestinal homeostasis. Interventions leveraging the interplay between the gut microbiota and gastrointestinal hormones have been employed in the clinical management of metabolic diseases and inflammatory bowel diseases, such as bariatric surgery and fecal microbiota transplantation, offering promising targets for the treatment of dysbiosis-related diseases.

Cross-feeding-based rational design of a probiotic combination of Bacterides xylanisolvens and Clostridium butyricum therapy for metabolic diseases

The human gut microbiota has gained interest as an environmental factor that contributes to health or disease. The development of next-generation live biotherapeutic products (LBPs) is a promising strategy to modulate the gut microbiota and improve human health. In this study, we identified a novel cross-feeding interaction between Bacteroides xylanisolvens and Clostridium butyricum and developed their combination into a novel LBP for treating metabolic syndrome. Using in-silico analysis and in vitro experiments, we demonstrated that B. xylanisolvens supported the growth and butyrate production of C. butyricum by supplying folate, while C. butyricum reciprocated by providing pABA for folate biosynthesis. Animal gavage experiments showed that the two-strain combination LBP exhibited superior therapeutic efficacy against metabolic disorders in high-fat diet-induced obese (DIO) mice compared to either single-strain treatment. Further omics-based analyses revealed that the single-strain treatments exhibited distinct taxonomic preferences in modulating the gut microbiota, whereas the combination LBP achieved more balanced modulation to preserve taxonomic diversity to a greater extent, thereby enhancing the stability and resilience of the gut microbiome. Moreover, the two-strain combinations more effectively restored gut microbial functions by reducing disease-associated pathways and opportunistic pathogen abundance. This work demonstrates the development of new LBP therapy for metabolic diseases from cross-feeding microbial pairs which exerted better self-stability and robust efficacy in complex intestinal environments compared to conventional single-strain LBPs.

Deciphering the role of APOE in cerebral amyloid angiopathy: from genetic insights to therapeutic horizons

Cerebral amyloid angiopathy (CAA), characterized by the deposition of amyloid-β (Aβ) peptides in the walls of medium and small vessels of the brain and leptomeninges, is a major cause of lobar hemorrhage in elderly individuals. Among the genetic risk factors for CAA that continue to be recognized, the apolipoprotein E (APOE) gene is the most significant and prevalent, as its variants have been implicated in more than half of all patients with CAA. While the presence of the APOE ε4 allele markedly increases the risk of CAA, the ε2 allele confers a protective effect relative to the common ε3 allele. These allelic variants encode three APOE isoforms that differ at two amino acid positions. The primary physiological role of APOE is to mediate lipid transport in the brain and periphery; however, it has also been shown to be involved in a wide array of biological functions, particularly those involving Aβ, in which it plays a known role in processing, production, aggregation, and clearance. The challenges posed by the reliance on postmortem histological analyses and the current absence of an effective intervention underscore the urgency for innovative APOE-targeted strategies for diagnosing CAA. This review not only deepens our understanding of the impact of APOE on the pathogenesis of CAA but can also help guide the exploration of targeted therapies, inspiring further research into the therapeutic potential of APOE.

Small molecules targeting the eubacterial β-sliding clamp discovered by combined in silico and in vitro screening approaches

Antibiotic resistance stands as the foremost post-pandemic threat to public health. The urgent need for new, effective antibacterial treatments is evident. Protein-protein interactions (PPIs), owing to their pivotal role in microbial physiology, emerge as novel and attractive targets. Particularly promising is the α-subunit/β-sliding clamp interaction, crucial for the replicative competence of bacterial DNA polymerase III holoenzyme. Through pharmacophore-based virtual screening, we identified 4,000 candidate small molecule inhibitors targeting the β-clamp binding pocket. Subsequently, these candidates underwent evaluation using the BRET assay in yeast cells. Following this, three hits and 28 analogues were validated via Protein Thermal Shift and competitive ELISA assays. Among them, thiazolo[4,5-d]-pyrimidinedione and benzanilide derivatives exhibited micromolar potency in displacing the β-clamp protein partner and inhibiting DNA replication. This screening campaign unveiled new chemical classes of α/β-clamp PPI disruptors capable of inhibiting DNA polymerase III activity, which lend themselves for further optimisation to improve their antibacterial efficacy.

Klebsiella pneumoniae derived outer membrane vesicles mediated bacterial virulence, antibiotic resistance, host immune responses and clinical applications

Klebsiella pneumoniae is a gram-negative pathogen that can cause multiple diseases including sepsis, urinary tract infections, and pneumonia. The escalating detections of hypervirulent and antibiotic-resistant isolates are giving rise to growing public concerns. Outer membrane vesicles (OMVs) are spherical vesicles containing bioactive substances including lipopolysaccharides, peptidoglycans, periplasmic and cytoplasmic proteins, and nucleic acids. Emerging studies have reported various roles of OMVs in bacterial virulence, antibiotic resistance, stress adaptation, and host interactions, whereas knowledge on their roles in K. pneumoniae is currently unclear. In this review, we summarized recent progress on the biogenesis, components, and biological function of K. pneumoniae OMVs, the impact and action mechanism in virulence, antibiotic resistance, and host immune response. We also deliberated on the potential of K. pneumoniae OMVs in vaccine development, as diagnostic biomarkers, and as drug nanocarriers. In conclusion, K. pneumoniae OMVs hold great promise in the prevention and control of infectious diseases, which merits further investigation.

Electrotherapy and health monitoring with piezoelectric and triboelectric technologies

The growing need for advanced therapeutic and diagnostic technologies has spurred interest in self-powered systems for electrotherapy and health monitoring. Traditional battery-dependent medical devices (MDs) face limitations, including short operational lifespans and patient discomfort, underscoring the importance of sustainable alternatives. Mechanical energy harvesting technologies, such as piezoelectric and triboelectric nanogenerators (PENGs and TENGs), have emerged as promising solutions, enabling real-time health monitoring and non-invasive electrotherapy by converting biomechanical energy into electricity. This review explores the latest advancements in PENG and TENG technologies, emphasizing their applications in wound healing, neural regeneration, and real-time physiological monitoring. Strategies to overcome hurdles are discussed, demonstrating the transformative potential of PENG and TENG systems in next-generation MDs. By integrating energy harvesting with therapeutic and monitoring functionalities, piezoelectric and triboelectric systems offer a path toward non-invasive, efficient, and patient-centric medical solutions.

The role of cisplatin in modulating the tumor immune microenvironment and its combination therapy strategies: a new approach to enhance anti-tumor efficacy

Cisplatin is a platinum-based drug that is frequently used to treat multiple tumors. The anti-tumor effect of cisplatin is closely related to the tumor immune microenvironment (TIME), which includes several immune cell types, such as the tumor-associated macrophages (TAMs), cytotoxic T-lymphocytes (CTLs), dendritic cells (DCs), myeloid-derived suppressor cells (MDSCs), regulatory T cells (Tregs), and natural killer (NK) cells. The interaction between these immune cells can promote tumor survival and chemoresistance, and decrease the efficacy of cisplatin monotherapy. Therefore, various combination treatment strategies have been devised to enhance patient responsiveness to cisplatin therapy. Cisplatin can augment anti-tumor immune responses in combination with immune checkpoint blockers (such as PD-1/PD-L1 or CTLA4 inhibitors), lipid metabolism disruptors (like FASN inhibitors and SCD inhibitors) and nanoparticles (NPs), resulting in better outcomes. Exploring the interaction between cisplatin and the TIME will help identify potential therapeutic targets for improving the treatment outcomes in cancer patients.

Mitochondrial dysfunction: the hidden catalyst in chronic kidney disease progression

Chronic kidney disease (CKD) represents a global health epidemic, with approximately one-third of affected individuals ultimately necessitating renal replacement therapy or transplantation. The kidney, characterized by its exceptionally high energy demands, exhibits significant sensitivity to alterations in energy supply and mitochondrial function. In CKD, a compromised capacity for mitochondrial ATP synthesis has been documented. As research advances, the multifaceted roles of mitochondria, extending beyond their traditional functions in oxygen sensing and energy production, are increasingly acknowledged. Empirical studies have demonstrated a strong association between mitochondrial dysfunction and the pathogenesis of fibrosis and cellular apoptosis in CKD. Targeting mitochondrial dysfunction holds substantial therapeutic promise, with emerging insights into its epigenetic regulation in CKD, particularly involving non-coding RNAs and DNA methylation. This article presents a comprehensive review of contemporary research on mitochondrial dysfunction in relation to the onset and progression of CKD. It elucidates the associated molecular mechanisms across various renal cell types and proposes novel research avenues for CKD treatment.

In vivo toxicity of chitosan-based nanoparticles: a systematic review

Chitosan nanoparticles have been extensively utilised as polymeric drug carriers in nanoparticles formulations due to their potential to enhance drug delivery, efficacy, and safety. Numerous toxicity studies have been previously conducted to assess the safety profile of chitosan-based nanoparticles. These toxicity studies employed various methodologies, including test animals, interventions, and different routes of administration. This review aims to summarise research on the safety profile of chitosan-based nanoparticles in drug delivery, with a focus on general toxicity tests to determine LD50 and NOAEL values. It can serve as a repository and reference for chitosan-based nanoparticles, facilitating future research and further development of drugs delivery system using chitosan nanoparticles. Publications from 2014 to 2024 were obtained from PubMed, Scopus, Google Scholar, and ScienceDirect, in accordance with the inclusion and exclusion criteria.The ARRIVE 2.0 guidelines were employed to evaluate the quality and risk-of-bias in the in vivo toxicity studies. The results demonstrated favourable toxicity profiles, often exhibiting reduced toxicity compared to free drugs or substances. Acute toxicity studies consistently reported high LD50 values, frequently exceeding 5000 mg/kg body weight, while subacute studies typically revealed no significant adverse effects. Various routes of administration varied, including oral, intravenous, intraperitoneal, inhalation, and topical, each demonstrating promising safety profiles.

RNase P cleavage of pseudoknot substrates reveals differences in active site architecture that depend on residue N-1 in the 5' leader

We show that a small biotin-binding RNA aptamer that folds into a pseudoknot structure acts as a substrate for bacterial RNase P RNA (RPR) with and without the RNase P C5 protein. Cleavage in the single-stranded region in loop 1 was shown to depend on the presence of a RCCA-motif at the 3' end of the substrate. The nucleobase and the 2'hydroxyl at the position immediately 5' of the cleavage site contribute to both cleavage efficiency and site selection, where C at this position induces significant cleavage at an alternative site, one base upstream of the main cleavage site. The frequencies of cleavage at these two sites and Mg2+ binding change upon altering the structural topology in the vicinity of the cleavage site as well as by replacing Mg2+ with other divalent metal ions. Modelling studies of RPR in complex with the pseudoknot substrates suggest alternative structural topologies for cleavage at the main and the alternative site and a shift in positioning of Mg2+ that activates the H2O nucleophile. Together, our data are consistent with a model where the organization of the active site structure and positioning of Mg2+ is influenced by the identities of residues at and in the vicinity of the site of cleavage.

Exploring the efficacy and constraints of platinum nanoparticles as adjuvant therapy in silicosis management

Silicosis represents a formidable occupational lung pathology precipitated by the pulmonary assimilation of respirable crystalline silica particulates. This condition engenders a cascade of cellular oxidative stress via the activation of bioavailable silica, culminating in the generation of reactive oxygen species (ROS). Such oxidative mechanisms lead to irrevocable pulmonary impairment. Contemporary scholarly examinations have underscored the substantial antioxidative efficacy of platinum nanoparticles (PtNPs), postulating their utility as an adjunct therapeutic modality in silicosis management. The physicochemical interaction between PtNPs and silica demonstrates a propensity for adsorption, thereby facilitating the amelioration and subsequent pulmonary clearance of silica aggregates. In addition to their detoxifying attributes, PtNPs exhibit pronounced anti-inflammatory and antioxidative activities, which can neutralize ROS and inhibit macrophage-mediated inflammatory processes. Such attributes are instrumental in attenuating inflammatory responses and forestalling subsequent lung tissue damage. This discourse delineates the interplay between ROS and PtNPs, the pathogenesis of silicosis and its progression to pulmonary fibrosis, and critically evaluates the potential adjunct role of PtNPs in the therapeutic landscape of silicosis, alongside a contemplation of the inherent limitations associated with PtNPs application in this context.

Influences of physical stimulations on the migration and differentiation of Schwann cells involved in peripheral nerve repair

Peripheral nerve injury repair has always been a research concern of scientists. At the tissue level, axonal regeneration has become a research spotlight in peripheral nerve repair. Through transplantation of autologous nerve grafts or other emerging biomaterials functional recovery after facial nerve injury is not ideal in clinical scenarios. Great strides have been made to improve facial nerve repair at the micro-cellular level. Physical stimulation techniques can trigger Schwann cells (SCs) to migrate and differentiate into cells required for peripheral nerve repair. Classified by the sources of physical stimulations, SCs repair peripheral nerves through galvanotaxis, magnetotaxis and durotaxis. This article summarized the activation, directional migration and differentiation of SCs induced by physical stimulations, thus providing new ideas for the research of peripheral nerve repair.

A surrogate BSL2-compliant infection model recapitulating key aspects of human Marburg virus disease

Marburg virus disease (MVD) is a severe infectious disease caused by the Marburg virus (MARV), posing a significant threat to humans. MARV needs to be operated under strict biosafety Level 4 (BSL-4) laboratory conditions. Therefore, accessible and practical animal models are urgently needed to advance prophylactic and therapeutic strategies for MARV. In this study, we constructed a recombinant vesicular stomatitis virus (VSV) expressing the Marburg virus glycoprotein (VSV-MARV/GP). Syrian hamsters infected with VSV-MARV/GP presented symptoms such as thrombocytopenia, lymphopenia, haemophilia, and multiorgan failure, developing a severe systemic disease akin to that observed in human MARV patients. Notably, the pathogenicity was found to be species-specific, age-related, sex-associated, and challenge route-dependent. Subsequently, the therapeutic efficacy of the MR191 monoclonal antibody was validated in this model. In summary, this alternative model is an effective tool for rapidly screening medical countermeasures against MARV GP in vivo under BSL-2 conditions.

RNA-seq analyses reveal the relevance of RNAs involved in ribosomal complex to induce mammalian prion protein aggregation and phase separation in vitro

Conformational conversion of cellular prion protein (PrPC) into infectious PrP (PrPSc) is one of the most intriguing processes in modern Biology. It is well accepted that this transition is catalysed by one or more cofactors that lower the energy barrier between the different PrP forms. Among potential candidates, RNA molecules are strong contenders. Our group has pursued nucleic acids, both DNA and RNA, capable of inducing PrP misfolding, aggregation, and, more recently, phase separation, a process proposed to precede aggregation in degenerative disorders. We found that the interaction between recombinant PrP (rPrP) and total RNA extracted from neuroblastoma cells (N2aRNA) results in significant structural alterations. Here, we use rPrP:N2aRNA as a model to search for RNAs capable of inducing full-length murine rPrP phase separation and/or aggregation. N2aRNA was incubated with rPrP and after that, RNA-seq analysis was conducted with RNAs isolated from the insoluble material using two different protocols. We analysed thousands of RNA-seq reads, most of which represented ribosomal RNA molecules. The set of recovered molecules is heterogeneous; nevertheless, three low-complexity consensus motifs within the sequences of RNAs involved in ribosomal complex were identified as significantly enriched in the RNAs bound to rPrP, suggesting that a population of RNAs is responsible for inducing PrP phase transitions. We hypothesize that RNA transcripts enriched in a set of low complexity motif sequences with predicted structural similarities can be involved in PrPC binding. This interaction would lead to phase separation and, ultimately, result in aggregation into scrapie-like species, in a stoichiometry-dependent manner.

Precursor of H-type II histo-blood group antigen and subterminal sialic acids on gangliosides are significantly implicated in cell entry and infection by a porcine P[11] rotavirus

Rotaviruses, non-enveloped viruses with a double-stranded RNA genome, are the leading etiological pathogen of acute gastroenteritis in young children and animals. The P[11] genotype of rotaviruses exhibits a tropism for neonates. In the present study, a binding assay using synthetic oligosaccharides demonstrated that the VP8* protein of P[11] porcine rotavirus (PRV) strain 4555 binds to lacto-N-neotetraose (LNnT) with the sequence Galβ1,4-GlcNAcβ1,3-Galβ1,4-Glc, one of the core parts of histo-blood group antigen (HBGA) and milk glycans. However, infections were significantly inhibited by blocking of endogenous monosialoganglioside (GM) GM1a with cholera toxin B subunit and preincubation of the virus with exogenous GM1a, suggesting that GM1a is involved in the infection of P[11] PRV 4555. In addition to GM1a, preincubation of the virus with exogenous disialogangliosides (GD) GD1a, GD1b, and trisialoganglioside (GT) GT1b also prevented infection. In contrast, exogenous ganglioside GM3 only inhibited infections at an early time point, and exogenous asyalosphingolipids GA1 and LacCer did not show any inhibitory effect on infections. This indicates that P[11] PRV 4555 preferentially utilizes gangliosides containing subterminal sialic acids. Further experiments revealed that P[11] PRV 4555 infections were prevented by preincubation of the virus with Neu5Ac and Neu5Gc. These results confirmed that sialic acids are essential for P[11] PRV 4555 cell entry, despite the classification as NA-resistant strain. Overall, our results proved that P[11] rotavirus not only binds to the Gal-GlcNAc motif but also utilizes gangliosides containing subterminal sialic acids.

New insights in amino sugar metabolism by the gut microbiome

Gut microorganisms inhabiting the intestinal tract play key roles in host's health and disease. A properly functioning gut microbiome requires the availability of adequate carbon, nitrogen and energy sources. One of the main sources of energy for intestinal bacteria are glycans, of which amino sugars are important components. Amino sugars are a class of carbohydrates in which one or more hydroxyl groups are substituted with amino groups. However, bacterial utilization of amino sugars and their impact on the gut microbiome and host health have not been thoroughly assessed. In this review, we summarize the latest discoveries about amino sugar metabolism by gut microbes, paying particular attention to the metabolism of N-acetyl-galactosamine (GalNAc), one of the most abundant amino sugars in the intestine, and its potential implications for microbial functionality and host health.

Identifying sex-based disparities in porcine mitochondrial function

In pigs, the effect of sex on production and reproductive traits has been largely reported, however, whether sex exerts its influence through regulating mitochondrial function is still unclear. In this study, we constructed 15 male cells and 15 female fibroblasts derived from 35-day and 50-day fetuses, newborn piglets and 1-year-old pigs to identify the sex effect on mitochondrial functions. Results indicated significant differences on cellular and molecular characteristics between male and female cells, including energy metabolic trait, mitochondrial DNA (mtDNA) replication and transcription, and mRNA expressions of mitochondrial biogenesis genes and mitoprotease genes. Referring to sex, males exhibited significantly higher oxygen consumption rate productions, levels of reactive oxygen species (ROS) and mtDNA copy numbers than those with females in muscle and ear fibroblasts. And the expressions of mtDNA, mitochondrial biogenesis genes (POLG, PPARGC1A, TFAM and TWNK) and XPNPEP3 were higher in males than females in ear fibroblasts derived from 1-year-old adult pigs (EFA cells). While, the cell proliferation and expressions of genes related to ROS metabolism were not influenced by sex. The results highlight the effect of sex on mitochondrial function and gene expression, and provide important data for a comprehensive understanding of the mechanisms underlying sex regulation of energy metabolism-related traits in pigs.

Caspase 3-specific cleavage of ubiquitin-specific peptidase 48 enhances drug-induced apoptosis in AML

Dysfunction or dysregulation of deubiquitination is closely related to the initiation and development of multiple cancers. Targeted regulation of deubiquitination has been recognized as an important strategy in tumor therapy. However, the mechanism by which drugs regulate deubiquitinase is not clear. Here, we identified ubiquitin-specific peptidase 48 (USP48), a member of the ubiquitin-specific protease family highly expressed in various tumors, as a specific substrate for the activated caspase-3. During drug induced apoptosis of AML cells, activated caspase-3 cleaves USP48 through recognizing the conservative motif DEQD located at 611-614 sites of human USP48. Subsequent analysis showed that the cleavage USP48 N-terminal fragment which contains catalytic active domain is easily degraded by ubiquitination. Meanwhile knockdown experiment showed that inhibiting the expression of USP48 could also promotes apoptosis and enhance the efficacy of chemotherapy drugs. Altogether, these results suggest that targeting USP48 may represent a novel therapeutic strategy in AML.

Endothelia-targeting eye drops deliver a STING inhibitor to effectively reduce retinal neovascularization in ischemic retinopathy

Retinal neovascularization is the main pathologic feature of ischemic retinopathy, which eventually leads to vision loss and even blindness. Current treatments like laser photocoagulation and intravitreal injection of anti-vascular endothelial growth factor A drugs are invasive, expensive, and incompetent. Therefore, it is urgent to explore optimized therapies, particularly eye drops, to improve treatment effects. Our recent study reported that abnormal up-regulation of stimulator of interferon genes (STING) is closely associated with retinal vascular diseases, and it is highly enriched in retinal endothelial cells with retinopathy. Thus, we evaluated whether endothelial STING affects retinal neovascularization. In addition, we constructed iRGD- and TAT-decorated nanoparticles (NPs) loaded with C-176 (I/T-C-NP), capable of penetrating the cornea and targeting retinal endothelial cells. The I/T-C-NP eye drops were applied to the eyes of oxygen-induced retinopathy mice, resulting in attenuated activation of the STING pathway. Consequently, retinal neovascularization and vascular tortuosity were effectively reduced, astrocyte activation was prohibited, and pericyte coverage was improved. These observations suggest that I/T-C-NP eye drops can be a potential solution for the treatment of retinal neovascularization.

Loading fluorescent dyes into MOF pores for the optical sensing and adsorption of heavy metal ions: synthesis, characterization, and performance

The detection and removal of Cu(II) cations are an important topic in environmental protection and human health. Optical sensing platforms based on luminescent probes seem attractive due to their optical signal outputs which are free of electromagnetic interference, low cost, fast response, and high sensitivity. In this work, two azobenzene-based sensing probes (P1 and P2) were synthesized, and their sensing performance was firstly evaluated by their spectroscopic response towards various ions. P1 showed good sensing selectivity towards Cu2+ by forming an adduct with stoichiometric ratio of 1:1, as confirmed by Job's plot, NMR, XPS, and EPR (electron paramagnetic resonance) comparison. P2 showed sensing behavior not only towards Cu2+ but also towards Fe2+, Fe3+, and Hg2+ due to the increased bonding affinity of -OH group. These two azobenzene-based probes were then covalently loaded into a MOF (metal-organic framework) matrix of bio-MOF-1 to endow it with optical sensing ability, as well as to improve the adsorption stability/capacity for metal cations. Pn@BMOF (n = 1, 2) samples were characterized by SEM, XRD, N2 adsorption/desorption, IR, and elemental analysis. Their optical sensing and adsorption performance for metal cations were evaluated as well. Linear working equations were obtained with quenching constants and LOD values of 0.0884 μM-1 and 0.22 μM for P1@BMOF, and 0.0998 μM-1 and 0.20 μM for P2@BMOF. The adsorption levels for Cu2+ were determined as 0.97 mmol/g for P1@BMOF and 1.03 mmol/g for P2@BMOF.

Asymmetric phenothiazine derivatives modified with diphenylamine and carbazole: Photophysical properties and hypochlorite sensing

This study reports the design, synthesis, and characterization of four asymmetric donor-acceptor (D-A) fluorescent molecules-1CAR, 1DIP, 1OOCAR, and 1OODIP-featuring phenothiazine (PTZ), diphenylamine (DIP), and carbazole (CAR) as electron donors. By oxidizing the sulfur atom in PTZ and modifying the molecular structure at the 3-position, we systematically investigated the influence of structural variations on photophysical properties. These compounds exhibit distinct solvatochromic behavior, aggregation-induced enhanced emission (AIEE), and mechanofluorochromism (MFC). Solvent-dependent fluorescence studies revealed significant red shifts with increasing polarity, confirming strong intramolecular charge transfer (ICT) characteristics, as further supported by Lippert-Mataga analysis. In aggregated states, 1CAR and 1DIP displayed remarkable AIEE, with fluorescence intensity enhancements of up to 84.1- and 9.7-fold, respectively, whereas 1OOCAR exhibited aggregation-caused quenching (ACQ) due to structural constraints. Solid-state fluorescence analysis highlighted the impact of PTZ oxidation on emission characteristics, demonstrating its critical role in tuning fluorescence properties. Additionally, the sensing capabilities of 1CAR and 1DIP toward hypochlorite ions (ClO-) were explored through UV-Vis and fluorescence titration experiments, revealing substantial fluorescence quenching with increasing ClO- concentrations. The detection limits reached as low as 0.68 µM, underscoring their high sensitivity and selectivity. This research offers important perspectives for the rational design of multifunctional fluorescent materials for applications in chemosensing and environmental monitoring.

Tracking chemical interactions of caspofungin on silver nanoparticles through SERS spectroscopy for antifungal applications

Silver nanoparticles (AgNP) act as efficient drug delivery carriers due to particular surface chemistry and high surface area, and even though such may present toxicity in function of the size distribution and molecular ion coverage, have been receiving special attention for their inhibitory potential against bacteria and fungi. This study explored the use of AgNP to deliver the antifungal caspofungin (CFG) for in vitro combating Candida albicans. CFG molecules were coadsorbed with low-weight chitosan (LWC) on AgNP surfaces, in the presence and absence of 2-mercaptoethanol (ME) surface modifier. Surface-enhanced Raman scattering (SERS) spectroscopy was used both to monitor the adsorption process and to assess the synergistic interaction between the components in actions against fungal cultures, observed by checkerboard assays. Results showed significant lowering of minimum inhibitory concentration (MIC) values for the CFG-LWC-AgNP ternary mixture in comparison with CFG alone. Transmission Electron Microscopy (TEM) images provided insights about the mechanism of action of components of the ternary mixture. Spectral analysis of CFG by using FT-Raman, FTIR, and SERS spectroscopies identified distinct spectral patterns, indicating effective chemical interactions of CFG on AgNP surfaces. The vibrational assignment of such spectra was done based on Density Functional Theory (DFT) calculations. Such findings suggest that AgNP could be a promising platform for enhancing the efficacy of CFG drug against fungal infections.

Enhanced detection of pesticides: evaluating monocarbamoylcarboxylic acids modified with amines for glyphosate and dicamba sensitivity

In this work a series of monocarbamoylcarboxylic acids (MCCAs) N-functionalized with different amines were evaluated to detect the pesticides glyphosate (Gly) and dicamba (Dic). The MCCAs have molar absorptivity coefficients (ε) three orders of magnitude higher than pesticides facilitating the measurements under UV-Vis spectroscopy. These compounds have the isolectric point (IEP) in the range of pH 3.04-4.82 and beyond are negative charged. The absorption properties of the compounds are pH-dependent due to the protonation and deprotonation of their molecules, the adsorption band shifts to a longer wavelength as the pH increases and in some ligands a hyperchromic effect is observed. The titration of MCCAs with a pesticide generates a change in the adsorption band and the sensitivity of the response is also pH-dependent. The sensitivity of MCCAs towards pesticides decreased at pH 5.0 and increased at pH 7.0 and 9.0 which is clearly influenced by the acid-base equilibriums in water. The response was more sensitive towards dicamba than with glyphosate, exhibiting linear concentration intervals up to 100 µM with 1a at pH 4 and 85 µM in compounds 2b and 2c at pH 7.0. The 1H NMR analysis in DMSO‑d6 of compounds 2a and 2c in presence of glyphosate and dicamba showed changes in the hydrogen signals indicating the interaction of these MCCAs with the pesticides in specific sites of their molecules. These MCCAs, proved to be promising molecular platforms for the optical detection of glyphosate and dicamba due to their pH-adjustable sensitivity and their ability to show significant electrostatic interactions, enabling pesticide detection over a wide concentration range.

A cyanine-based probe for sensitive and selective detection of mustard gas simulant CEES

A novel cyanine dye-based probe, Cy3CS, was developed and evaluated for the detection of 2-chloroethyl ethyl sulfide (CEES), a simulant for sulfur mustard which is a notorious chemical warfare agent. The probe demonstrated a substantial (as high as 106-fold) fluorescence enhancement upon reaction with CEES even at low concentrations (0.1-1 mM and 0-100 μM). The detection displayed excellent linear correlation between fluorescence intensity and CEES concentration with high R2 values (0.9954 and 0.9993 for 0.1-1 mM and 0-100 μM, respectively) and low detection limit (0.44 μM). Meanwhile, the detection does not involve base or other additives, which could simply the detection procedure. The selectivity experiments revealed that the probe responded exclusively to CEES among a range of potential interferents, proving the superior specificity. This selectivity is crucial for accurate detection in complex environments, such as soil samples, which were effectively analyzed using our probe. Thus, the Cy3CS probe offers a significant advancement in the detection of chemical warfare agent's simulant, with performance metrics that include excellent sensitivity, selectivity, and simplicity of use, establishing it as a promising tool for environmental monitoring and public health safety.

A novel BODIPY probe for efficient detection and Photoinactivation of E.coli

Bacterial metabolism is related to pathogenicity, which lead to numerous diseases and pose significant threats to human health. Therefore, the development of metabolism-responsive probes is essential for early detection and effective treatment. In this study, we designed a novel BODIPY-based fluorescent probe (NH2-BIN) targeting Escherichia coli (E. coli), guided by its copper homeostasis mechanism. NH2-BIN exhibits high selectivity toward Cu2+ ions, forming a non-emissive complex (NH2-BIN-Cu). Remarkably, E. coli is capable of restoring the fluorescence of NH2-BIN-Cu through copper-binding and redox activity. The probe demonstrates an "on-off-on" fluorescence response with detection limits of 15 nM for Cu2+ and 1.04 CFU/mL for E. coli. Furthermore, NH2-BIN-Cu displays photo-induced antibacterial activity against E. coli under red LED irradiation. These results highlight NH2-BIN as a metabolism-driven, E. coli-responsive "sense-and-treat" fluorescence probe, offering a promising approach for precise detection and red-light-activated antibacterial therapy.

An Au@CuS@CuO2 nanoplatform with peroxidase mimetic activity and self-supply H2O2 properties for SERS detection of GSH

The abnormal fluctuations of glutathione (GSH) in vivo often reflect disease progression and are closely linked to human metabolism and physiological functions. Highly sensitive and selective detection of GSH is crucial for guiding early diagnosis and treatment; however, achieving this remains a significant challenge. In this study, we developed an enzyme activity sensor platform for the efficient detection of GSH. This platform utilizes Au@CuS core-shell materials loaded with CuO2 nanoparticles to create a composite nanosensor system. Under slightly acidic conditions, CuO2 on the nanomaterial's surface decomposes into H2O2 and Cu2+ ions. The generated H2O2 then reacts with tetramethylbenzidine (TMB) in the presence of peroxidase-like CuS to yield oxidized tetramethylbiphenyl (OXTMB), which generates a distinctive Raman signal. Upon addition of GSH to the system, the unique OXTMB signal diminishes due to GSH's strong antioxidant capacity and the consequent consumption of OXTMB. This sensing method enables sensitive detection of GSH, with a detection limit as low as 1.2 × 10-13 mol∙L-1. This approach holds promise for providing researchers with rapid and precise in vitro analysis of GSH, serving as an indicator for early disease diagnosis and real-time evaluation of treatment efficacy.

Specific imaging of hydrogen sulfide in paw edema mice via a novel near-infrared fluorescent probe with large stokes shift

Paw edema is a classic acute inflammation model, which is often used in clinical screening and evaluation of anti-inflammatory effects of drugs. As an endogenous gas signaling molecule, hydrogen sulfide (H2S) is closely related to the progression of paw edema inflammation. However, no fluorescent probes have been reported to visualize H2S levels in paw edema mice. Herein, a novel near-infrared (NIR) fluorescent probe (BAX-N) is developed to detect H2S. The NIR dye formed by the conjugation of benzothiazole-2-acetonitrile with xanthene serves as the fluorophore (BAX-OH), and nitrobenzoxadiazole (NBD) serves as the H2S-responsive group. The fluorescence of BAX-N is quenched due to the photo-induced electron transfer (PET) effect. After the reaction of BAX-N with H2S, the PET effect is blocked and obvious fluorescence appears at 722 nm, while exhibiting large Stokes shift, fast response time, high sensitivity and selectivity. Meanwhile, the possible reaction mechanism of BAX-N toward H2S was proposed and proved by mass spectra (MS), high-performance liquid chromatography (HPLC) and Density functional theory (DFT) calculation. Furthermore, based on the high biosafety of BAX-N, it has been used to monitor fluctuation in H2S levels in cells during inflammatory events. More importantly, BAX-N has been first used for specifically image H2S in paw edema mice and its treatment due to its NIR properties, which will provide a reliable platform for the monitoring of inflammatory conditions and the evaluation of anti-inflammatory drug efficacy.

Quasi-intrinsic cytosine analogues for two-photon photodynamic therapy with Type I/II mechanism

Two-photon photodynamic therapy (TP-PDT) provides a broad prospect for cancer treatment due to its deep penetration, minimal invasiveness and fewer side effects. In this work, a series of quasi-intrinsic photosensitizers (PSs) are proposed for TP-PDT based on the cytosine. To ensure the efficient intersystem crossing rates and strong absorption within the therapeutic window (600-900 nm), the ring-expansion and substitution of F and Cl halogen atoms are considered. Our calculations revealed that these C-analogues could maintain the fundamental pyrimidine skeleton with inherently planarity and possess relatively low logP values contributing to their enhanced cancer cell-targeting capability. More importantly, the modifications could bring significant red-shifted one-photon absorption and enlarged two-photon absorption cross-section that responsible for selective excitation during PDT. Following the vertical photoexcitation, the population in the long-lived triplet state are characterized by examining the deactivation rates and the corresponding decay lifetime. Additionally, the generation of reactive oxygen species for PDT is confirmed through calculations of ionization potential as well as electron affinity (type I mechanism), and the T1 energy (type II mechanism). Besides, the effects of base pairing on photosensitivity are investigated to evaluate the usefulness of proposed PSs in TP-PDT. These nucleobase derivatives are expected to contribute broader advancement of PDT and provide theoretical clues for enhancing cancer treatment efficacy with reduced cytotoxicity and improved biocompatibility.

Synthesis and characterization of a solvatochromic urea-schiff base derivative: Investigating optical properties, hydrogen bonding effect, copper ion sensing, computational analysis, DNA and β-cyclodextrin interactions

This study investigates the fluorescence behavior of the synthesized compound (E)-1-(4-chloro-2-(((2-hydroxynaphthalen-1-yl) methylene) amino) phenyl)-3-(naphthalen-1-yl) urea (3DB) in various solvents. A significant increase in fluorescence intensity was observed when transitioning from ethanol to less polar solvents like CH2Cl2, CHCl3, and CCl4, indicating enhanced fluorescence due to reduced non-radiative processes. Emission wavelengths remained stable with minor shifts (5-6 nm), while significant blue shifts in absorption occurred in water due to strong hydrogen bonding. Fluorescence spectra showed red shifts (519 nm in water, 508 nm in glycerol, and 486 nm in ethylene glycol), highlighting the impact of hydrogen bonding on electronic transitions. Emission intensity in water was six times higher than in ethylene glycol, suggesting that strong hydrogen bonds stabilize the excited state. The study also revealed that 3DB exhibits a large Stokes shift, avoiding reabsorption of emitted light (inner filter effect). Fluorescence was completely quenched by low concentrations of copper ions, demonstrating 3DB's potential as a copper sensor. Density functional theory (DFT) and time-dependent DFT (TDDFT) calculations indicated that luminescence quenching in the Cu(II) complex is due to intramolecular charge transfer (ICT). Additionally, 3DB formed stable complexes with DNA and β-cyclodextrin (β-CD), with binding constants (Kb) of 1.30 × 103 M-1 and 1.89 × 103 M-1, respectively, and negative Gibbs free energy values, indicating spontaneous interactions. Fluorescence spectroscopy confirmed DNA binding, showing a 49.62 % increase in intensity and a 4 nm blue shift, consistent with groove-binding. Docking studies further supported favorable interactions with DNA. These results underscore 3DB's potential in sensing, imaging, environmental monitoring, and biological applications.

Regulating aggregation and optical properties of rigid-flexible ligand via metal coordination for multifunctional applications

Non-covalent interactions typically drive molecular aggregation, but precisely controlling supramolecular interactions to regulate molecular stacking configurations and expand practical applications remains challenging. Herein, we design and synthesize a rigid-flexible ligand Tpy-Py, incorporating one terpyridine (Tpy) and two pyrenes (Py) moieties. Whose aggregation state is regulated by metal coordination, thereby significantly modulating its optical properties. Tpy-Py exists as monomers in solution and forms excimers in the solid state, with emission shifting from blue to green. Single-crystal analysis reveals that Tpy-Py molecules form H- and J-aggregates via π-π stacking in the crystal, while coordination with Zn2+ and Cu2+ further tunes the molecular packing, leading to red-shifted emission or quenching. Moreover, the photochromic properties of Tpy-Py are effectively utilized in fingerprint detection, anti-counterfeiting, and visual detection of heavy metal ions. This work provides a new approach for regulating aggregation via non-covalent interactions and highlights the potential of Tpy-Py in multifunctional applications.

Detection of mitophagy in live cells with indole derived near-infrared fluorogenic probes

Mitophagy is an indispensable cellular process that plays a crucial role in regulating mitochondrial quality control and cellular metabolism. Therefore, monitoring the changes in the mitochondrial and lysosomal microenvironment during the mitophagy process is extremely important. However, existing mitophagy probes only target changes in a single indicator (viscosity, pH value, or polarity) within the microenvironment, which may reduce the selectivity and accuracy of assessing mitophagy in complex biological settings. To address this, we have developed a dual-channel detection near-infrared (NIR) fluorescent probe (ADMI). In vitro analysis experiments have shown that ADMI not only responds to pH and activates the NIR fluorescence channel but also that the green fluorescence channel exhibits high sensitivity to changes in polarity. This dual-response mechanism probe enables dual fluorescent detection of pH and polarity, providing a highly promising tool for monitoring the microenvironment of mitophagy in living cells. Ultimately, we applied ADMI to real-time monitoring of mitophagy induced by starvation or rapamycin, during which the decrease in pH and polarity resulted in a red shift in wavelength and increased fluorescence. Additionally, ADMI was able to observe changes in mitochondria during ferroptosis. This probe may serve as a useful tool for imaging mitophagy in living cells.

Toward routine basil (Ocimum basilicum L.) callus culture analysis using non-destructive Raman spectroscopy

Here we investigated whether FT-Raman spectroscopy could be used to detect biochemical changes in small-leaved basil (Ocimum basilicum L. var. minimum Alef.) callus culture (CC). To address the effect of culture conditions and elicitor treatments, CC established on 1 mg L-1 2,4-D + 0.5 mg L-1 BAP, or 2.5 mg L-1 NAA + 0.5 mg L-1 KIN was exposed to various spectral light treatments during four weeks and compared to those grown in dark. The composition of CC was analysed both using an FT-Raman spectrometer equipped with laser 1064 nm, and spectrophotometrically. The spectral composition of light had a higher influence on the chemical composition of CC grown on NAA + KIN than on 2,4-D + BAP medium. Spectrophotometrically, no differences in the content of protein or sugar were determined in relation to the plant growth regulators applied. However, significant differences in frequencies and intensities of vibrational bands associated with proteins (S-S disulfide stretching, tyrosine, cystine, and methionine at lower spectral ranges, and amide III stretching in the higher spectral range), and carbohydrates (C-O-C skeletal mode at lower spectral ranges, and C-O-H vibrations at higher spectral ranges) within the Raman spectra were estimated and discussed. The 1525 cm-1 and 1606 cm-1 peaks with high intensities of vibration bands were identified and assigned to carotenoids and phenolics. In all treatments applied the major Raman peaks were detected at 1606, 1629, and 1633 cm-1. PCA analysis showed that CC under blue-red light and blue-red light + UVa (2,4-D + BAP) had higher content of carotenoids and ester groups, while chlorophyll a and phenolics were found in CC grown on NAA + KIN under blue-red light + UVa and blue-red light + far-red. Compared to traditional methods of analysis, which are preceded by the sample destruction before extraction and analysis, it can be concluded that the FT-Raman spectroscopy may serve as a valuable tool for the non-destructive and non-invasive identification of major biochemical changes in basil CC without any sample preparation.

Comparison of spectroscopic techniques for determination of protein secondary structure

Determination of the protein secondary structure is a key task in academic and industrial fields related to biotechnology and the pharmaceutical sciences. Spectroscopic techniques offer the potential for rapid estimation of individual shares of secondary structures. In this work, 17 model proteins with known secondary structure were analysed by infrared (IR), Raman, far-UV circular dichroism (CD) spectroscopy and polarimetry. The recorded spectra were evaluated using PLS analysis (IR, Raman) and multiple dedicated algorithms (far-UV CD). Resulting figures of merit were compared and the application parameters of each spectroscopic technique were discussed. The best results were obtained from PLS models of IR and Raman spectra for the estimation of α-helix and β-sheet secondary structures. Far-UV CD spectroscopy combined with the CONTINLL algorithm achieved good figures of merit for α-helix and β-sheet. Polarimetry was shown to give good results for the analysis of α-helix.

Investigating the composition of the layer formed on Au NRs by NADH reduction and its application in SERS detection of Cu2

Surface metal deposition is an important method for tuning the optical property of plasmonic nanoparticles. In this work, we tried to deposit Cu shell on the surface of gold nanorods (Au NRs) by dihydronicotinamide adenine dinucleotide (NADH)-mediated reaction. Cu2+ were reduced to Cu0 through the gold-catalyzed oxidization of NADH. The deposition of Cu shell onto the Au NRs surface resulted in the obvious red-shift of longitudinal localized surface plasmon resonance peak. And the red-shift of longitudinal peak increased with the concentrations of NADH and Cu2+. The TEM images showed that a transparent layer structure with a different contrast around Au NRs was clearly displayed. And this transparent layer structure with the low contrast was generally considered to be pure Cu shell. However, the results from energy dispersive spectrometer (EDS) and X-ray photoelectron spectroscopy (XPS) indicated that the transparent layer was not just pure Cu composition, but contained NADH/NAD+ and Cu2+ components. This grown complex dielectric shell resulted in the reduced surface enhanced Raman scattering (SERS) activity of Au NRs. Based on the decreased SERS intensity, we demonstrated a SERS method for Cu2+ detection using R6G as Raman reporter. The decreased SERS intensity had a linear correlation with the concentration of Cu2+ in the range of 10-6-10-2 M, with a detection limit of 3.89 × 10-6 M. This study provides new insights about Cu deposition on Au NRs, which will further promote the spectral sensing applications with gold-catalyzed Cu2+ reduction on plasmonic nanoparticles by NADH.

Novel colorimetric sensor based on aggregation of noble metal nanomaterials for authenticity identification of Lycium ruthenicum from different regions

Lycium ruthenicum (Black goji berry, BGB) is a precious traditional Chinese medicine with numerous health benefits, highly sought after by consumers. However, its quality and price are greatly influenced by geographical location. Criminal adulterate such as inferior quality goji berries into genuine goji berries often occurs in the market, which results in huge economic losses. In this study, a novel method based on 3-aminobenzoic acid (PABA) modified gold nanoparticle clusters (PABA-AuNPs) was developed, utilizing noble metal nanomaterials combined with partial least squares discriminant analysis (PLS-DA) model for rapid and accurate identification of the origin of black goji berry. The recognition mechanism of this system was mainly due to the hydrogen bonding interaction between the -COO- groups on the surface of PABA and the amino acid compounds in black goji berries. This approach exhibited enhanced sensitivity, specificity, and simplicity, achieving 100% accurate identification of black goji berry origin. The successful application of PABA-AuNPs colorimetric sensing in tracing the origin of black goji berry has laid the foundation for the rapid on-site identification of the origin of other food and medicinal materials.

Mechanism of selenium-doped black phosphorus nanosheets wrapped with biomimetic tumor cell membrane for prostate cancer immunotherapy

Prostate cancer (PCa) is commonly considered a "cold tumor" due to its immunosuppressive microenvironment. Cold tumors are typically identified by the absence of T-cell infiltration within the tumor, while other immune populations and myeloid cells can be observed in these tumors. To achieve light-heat combined immunotherapy checkpoint inhibitor treatment for castration-resistant prostate cancer, we aimed to transforming "cold tumors" into "hot tumors". We designed and synthesized a two-dimensional material, selenium-doped black phosphorus (BP), to enhance the photothermal conversion efficiency, and formed Se@BPNSs by liquid-phase exfoliation. To address the issue of enhanced permeability and retention effect, and to achieve efficient targeting, we coated the Se@BPNSs with RM-1 cell membrane derived from mouse prostate cancer cells. By injecting a certain dose of Se@BPNSs into the tumor and irradiating with a 808 nm laser, the Se@BPNSs converted light energy into heat to kill tumor cells at high temperatures while releasing antigens captured by dendritic cells. In addition, we combined the immunotherapy checkpoint inhibitor anti-PD1 to enhance the immune response and promote immune cell infiltration. The successful preparation of Se@BPNSs was verified through material characterization, cell-level and animal-level experiments, and the antitumor effect was meanwhile verified, which further provided guidance for prostate cancer treatment by photothermal synergistic immunotherapy.

Biotinylated nanoparticles: A new frontier in nanomedicine and targeted cancer therapy

The development of targeted drug delivery systems has become a cornerstone of modern cancer therapy which provides a pathway to maximize treatment effectiveness while reducing side effects. Among the plethora of innovative strategies, biotinylated nanoparticles have evolved as a hopeful tool due to their ability to exploit the elevated expression of biotin receptors on cancerous cells. The design, synthesis, and functionalization of biotinylated nanoparticles for cancer treatment are thoroughly examined in this review article. By leveraging biotin's high affinity for biotin receptors, these nanoparticles achieve selective cancerous cell targeting, leading to enhanced drug bioavailability and cellular uptake. The discussion extends to the underlying mechanisms of drug release, receptor-mediated endocytosis, and strategies for achieving endosomal escape or pH-sensitive drug activation. Furthermore, the article also emphasizes how biotinylation in combination therapy allows for synergistic effects with immunomodulators, nucleic acids, and chemotherapeutic drugs. Preclinical studies are examined to underscore the translational potential of these systems. The review concludes by addressing current challenges, including scalability, and potential immunogenicity, while proposing future directions for optimizing biotinylated nanoparticles as a transformative approach in cancer treatment.