Search Results (2,078)

Obesity is increasingly recognized as a disease of dysregulated intercellular communication rather than merely an energy imbalance. Extracellular vesicles (EVs), membrane-bound nanoparticles (30–1000 nm) released by nearly all cell types, act as central mediators of this pathological crosstalk. In obesity, hypertrophic adipocytes, pro-inflammatory macrophages, and dysfunctional endothelial cells secrete EVs carrying altered cargo, including pro-inflammatory miRNAs (e.g., miR-34a, miR-155), bioactive lipids, and stress proteins, which propagate systemic metabolic dysfunction. Adipose tissue-derived EVs impair hepatic fatty acid oxidation, promote steatohepatitis, suppress pancreatic beta-cell insulin secretion, induce skeletal muscle insulin resistance via PPARγ repression, and contribute to endothelial dysfunction and atherosclerosis. EV-mediated adipocyte–macrophage crosstalk reinforces chronic adipose inflammation. Circulating EVs also provide biomarkers: subpopulation ratios, miRNA signatures, and tissue factor-positive EVs reflect disease severity, predict cardiovascular risk, and monitor therapeutic responses, with machine learning enhancing diagnostic precision. Therapeutically, EVs from mesenchymal stem cells, Wharton’s jelly MSCs, adipose progenitors, and M2 macrophages reverse insulin resistance, hepatic steatosis, and adipose inflammation in preclinical models. Engineering strategies improve EV potency and tissue targeting, and Phase I trials confirm safety, though manufacturing and cost remain barriers. Preclinical and early clinical studies of MSC-EVs confirm a favorable safety profile, though manufacturing scalability and cost remain barriers to widespread clinical adoption. Overall, EVs represent both diagnostic tools and therapeutic vehicles in precision obesity medicine, offering a pathway from symptom management toward true disease remission. Full article

Ubiquitin-specific protease 2 (USP2) is a deubiquitinase that controls various cellular events, including cell cycle progression and tumorigenesis. Along with cell culture models, mouse models induced using chemical blockers and gene engineering have substantially contributed to our knowledge of the crucial roles of USP2 in energy metabolism and metabolic disorders. This review summarizes the evidence of the role of USP2 in regulating energy metabolism in mice and cells under physiological and pathological conditions. In hepatocytes, a short isoform of USP2, USP2b, aggravates type 2 diabetes and metabolic dysfunction-associated steatotic liver disease. Meanwhile, a long isoform of USP2 in adipose tissue macrophages, USP2a, attenuates the onset of diabetes. USP2a mitigates insulin resistance and subsequent muscle atrophy. In ventromedial hypothalamic neurons, USP2b inhibits an increase in blood glucose by repressing hepatic glycogenolysis. In addition to regulating diabetes, USP2 isoforms potentially regulate the progression of atherosclerosis by modulating macrophages and hepatocytes. In brown adipose tissue, USP2a regulates thermogenesis, thus influencing systemic energy control. Meanwhile, in testicular macrophages, USP2 protects the mitochondrial respiration of sperm and consequently contributes to maintaining the quality of frozen sperm for use in the treatment of male infertility. As USP2 is distributed to multiple cellular components, it mediates the polyubiquitination of various molecules. For instance, USP2 modulates the stability of various transcription regulators, including C/EBP-α, PPARγ, EBF2, and PGC1α. The accumulating evidence indicates that USP2 functions as a modulatory molecule for energy metabolism across organs. Full article

The deterioration of mechanical properties and seepage issues in fractured rock masses represent critical technical bottlenecks in the field of geotechnical engineering. Traditional remediation techniques suffer from drawbacks such as environmental pollution, poor filling effects in microfissures, and susceptibility to secondary cracking, making it difficult to meet the requirements for long-term effectiveness and environmental compatibility in fractured rock mass reinforcement. Microbially induced calcium carbonate precipitation (MICP) technology, which drives the formation of calcium carbonate crystals through microbial metabolic activities, achieves fracture filling and rock mass reinforcement. This technology offers several advantages, including environmental friendliness, high permeability, and excellent compatibility; thus, it represents a cutting-edge direction for green remediation in geotechnical engineering. In this paper, the core mineralization mechanisms of MICP technology, key influencing factors, and engineering applications in fractured rock masses are systematically analysed. Research has indicated that MICP can significantly increase the compressive strength, impermeability, and liquefaction resistance of fractured rock masses, enabling both self-healing of rock fractures and precise filling of existing fissures. Compared with traditional techniques, it demonstrates superior environmental compatibility and remediation efficacy. This review aims to serve as a reference for theoretical research and engineering applications of MICP in fractured rock mass reinforcement. Full article

Human induced pluripotent stem cell (iPSC)-derived brain organoids have emerged as powerful three-dimensional (3D) platforms for modeling human neurodevelopment and neurological disorders. However, the absence of a functional vascular network remains a critical limitation, restricting oxygen and nutrient delivery, impairing metabolic stability, and constraining long-term maturation. Conventional extracellular matrix (ECM) mimetics, such as Matrigel and other static synthetic hydrogels, provide biochemical support but fail to recapitulate the dynamic remodeling that characterizes the developing neurovascular niche. Recent advances in stimuli-responsive hydrogels offer spatiotemporal control over matrix stiffness, degradability, viscoelasticity, and biochemical cue presentation. In this review, we discuss dynamic hydrogel systems within a structure–property–function framework, highlighting how network chemistry and architecture may regulate endothelial sprouting, lumen formation, vascular stabilization, and neurovascular unit maturation in vascularized brain organoid models, based on evidence from both organoid studies and related biomaterial or vascular systems. Photoresponsive, enzyme-cleavable, thermo-responsive, supramolecular, bio-orthogonal click-based, and bioprinted platforms are discussed with emphasis on mechanotransduction, angiocrine signaling, and barrier specialization. Functional outcomes, including trans-endothelial electrical resistance, selective permeability, transporter expression, electrophysiological integration, and sustained perfusion, are discussed alongside translational challenges such as cytocompatibility, oxidative stress, scalability, and regulatory feasibility. Collectively, dynamic hydrogels provide a versatile biomaterial strategy for improving vascularization and aspects of functional maturation in brain organoid models with enhanced physiological relevance. Ultimately, stimuli-responsive hydrogel systems may serve as enabling platforms for engineering vascularized brain organoids and advancing human-relevant neurovascular disease modeling. Full article

The optimization of membrane permeability is a pivotal approach for mitigating late-stage failures in peptide drug development. By leveraging linker chemical diversity, stapled peptides utilize linker engineering to precisely modulate key physicochemical parameters—such as lipophilicity and conformational constraints—to overcome the desolvation energy penalty. This review systematically evaluates linker-based strategies for enhancing the permeability of stapled peptides, categorized into two primary dimensions: (1) high-throughput screening (HTS) compatibility, focusing on the integration of functionalized linkers into mRNA display, phage display, and DNA-encoded libraries (DELs) to identify lead scaffolds with inherent permeability potential during early discovery; and (2) post-screening structural refinement, covering rational design strategies including intramolecular hydrogen-bond (IMHB) shielding, “chameleonic” adaptations, and stimuli-responsive reversible stapling. Furthermore, we analyze the paradigm shift in assessment methodologies from qualitative imaging to quantitative cytosolic delivery assays, which have deepened our understanding of mechanisms such as the charge/lipophilicity threshold balance and metabolism-driven trapping. Overall, linker engineering provides a robust technical roadmap for developing the next generation of cell-permeable stapled peptide therapeutics. Full article

Drought stress severely limits plant growth and productivity, yet the molecular basis of drought tolerance and post-drought recovery remains incompletely understood in many forage legumes. Medicago ruthenica is a perennial legume native to arid and cold regions and exhibits strong drought resilience. Results: We integrated key physiological traits related to stomatal regulation, photosynthesis, osmotic adjustment and antioxidant defense with RNA-seq across four stages (well-watered control, CK; drought for 9 days, D9; drought for 12 days, D12; and rewatering for 4 days, RW). Drought triggered stage-dependent physiological shifts, and transcriptome profiling identified >3000 drought- and rewatering-responsive genes enriched in primary metabolism, redox homeostasis and hormone signaling. WGCNA highlighted two drought-associated modules (MEcyan and MEcoral1) and prioritized three hub transcription factors for functional validation: 861 (AP2/ERF), 22 (WRKY) and 89 (bZIP). Overexpression of each gene in tobacco improved drought tolerance, as indicated by enhanced growth/root traits, increased osmolyte accumulation and antioxidant enzyme activities, and reduced membrane damage. Conclusions: Together, these results provide an integrated view of drought stress response and recovery in M. ruthenica and identify 861, 22 and 89 as candidate regulatory genes for engineering drought resilience in legumes. Full article

Sporulation represents a complex metabolic reprogramming process in bacteria. In this study, we used CRISPR-Cpf1 to knock out spoIIE and rsfA in Bacillus licheniformis. The ΔspoIIE strain completely lost sporulataion capacity, while ΔrsfA showed a 25% reduction. Although viable cell counts decreased by 80.7% and 45.7%, respectively, glucose consumption and 2,3-butanediol synthesis remained unchanged, and acetoin synthesis increased by 19% in ΔspoIIE. Per-cell metabolic rates were significantly enhanced: glucose uptake increased 2.7–3.4-fold, acetoin synthesis 2.3–4.2-fold, 2,3-butanediol synthesis 1.7-fold, and heterologous protein expression 10–15-fold. These findings demonstrate that blocking sporulation liberates metabolic resources and enhances the specific productivity of vegetative cells, providing a strategy for engineering high-performance B. licheniformis cell factories. Full article

Milbemycin D is a promising 16-membered macrolide insecticide with reported superior efficacy, but its commercial development has been hindered by extremely low natural yields. This study aimed to construct a high-yielding microbial platform for milbemycin D production using combinatorial biosynthesis and advanced genome editing. An optimized CRISPR/Cas9-AcrIIA4 system was employed to seamlessly replace the aveA3 polyketide synthase (PKS) gene in the ivermectin B1b-producing strain Streptomyces avermitilis HU501 with the heterologous milA3 PKS from S. bingchenggensis. The engineered strain was validated genetically and metabolically, followed by high-throughput screening and fermentation optimization in various media. The biosynthesized compound was structurally confirmed by spectroscopy. Bioactivity was evaluated against Bursaphelenchus xylophilus, Hyphantria cunea, and Plutella xylostella. The engineered strain S. avermitilis HU501-M successfully shifted its major product to milbemycin D, reaching a final titer of 679.03 mg/L. Bioassays revealed that milbemycin D exhibited significantly enhanced potency, with LC₅₀ values 8–24% lower than those of milbemycin A3/A4. This work demonstrates an efficient CRISPR/Cas9-mediated PKS replacement strategy to achieve the high-yield production of milbemycin D, offering a promising microbial source and a generalizable framework for engineering complex polyketide pathways. This proof-of-concept establishes a foundation for future process development toward potential commercial application. Full article

The 2025 approval of the selective NaV1.8 blocker suzetrigine for acute pain marked a pivotal advance in analgesic drug development. Yet the subsequent failure of Vertex’s next-generation NaV1.8 inhibitor VX993 to demonstrate clinical analgesia underscores enduring challenges in translating mechanistic promise into patient benefit. This review examines why promising targets and compounds, spanning NaV and TRP channels, often falter and outlines a path toward more reliable target selection and validation. I first summarize the pain pathway, from nociceptor transduction through spinal processing to cortical perception, emphasizing how inflammation and peripheral sensitization reshape excitability. Historically serendipitous, pain drug discovery now prioritizes molecular precision. Most approved chronic pain therapies act in the CNS and are limited by modest efficacy and adverse effects. Nociceptor-enriched targets (NaV1.7/1.8/1.9; TRP channels) remain attractive, yet redundancy among NaV subtypes and the necessity of blocking targets at the correct anatomical sites complicate translation. Human genetics and multi-omics provide a powerful, unbiased engine for target discovery. Rare high-impact variants offer strong causal hypotheses, while common polygenic contributions illuminate broader susceptibility. Large biobanks increasingly reveal a mismatch between legacy pain targets and genetically supported candidates across neuronal and non-neuronal cells. Human DRG transcriptomics highlight NaV channel redundancy. Human in vitro electrophysiology and PK/PD analyses show suzetrigine achieves ~90–95% NaV1.8 engagement, yet neurons can still fire unless additional channels are blocked. Species differences and drug distribution (including BBB/PNS penetration and P-gp efflux) critically influence efficacy; centrally accessible blockade (e.g., for NaV1.7 or TRPA1) may be necessary to achieve robust analgesia, challenging peripherally restricted strategies. Osteoarthritis illustrates how obesity-driven metabolic inflammation, synovial immune activation, subchondral bone remodeling, and specific nociceptor subtypes converge to drive mechanical pain. Multi-omic integration across diseased human tissues can pinpoint causal processes and cell types, enabling more selective and safer target choices. I propose a practical framework for target validation that integrates: (i) rigorous human genetic support; (ii) cell-type and site-of-action mapping; (iii) human-relevant electrophysiology and PK/PD with verified target engagement; (iv) species-appropriate models; (v) consideration of modality (small molecule, biologic, RNA, targeted protein degradation). Advancing genetically and anatomically aligned targets, tested at the right sites and exposures, offers the best path to genuinely effective, better-tolerated pain therapeutics. Full article

Effective oral interventions for alcohol-induced metabolic stress and liver injury remain limited. Pre-absorptive gastrointestinal alcohol handling is gaining interest as a non-pharmacological strategy to reduce hepatic burden. In this study, we developed a formulation-integrated, food-compatible lyophilized recombinant whole-cell catalyst based on Escherichia coli Nissle 1917 engineered to express alcohol dehydrogenase and acetaldehyde dehydrogenase. Rather than focusing exclusively on strain-level genetic modification, the engineered cells were protected by lyophilization combined with a food-grade chitosan–alginate layer-by-layer coating, forming an artificial cell wall designed to enhance survivability during oral delivery. The formulation resisted simulated gastric acid, sodium taurocholate, and ethanol, retained enzymatic activity after storage, and demonstrated formulation stability. In alcohol-exposed mice, oral administration reduced blood ethanol and acetaldehyde levels, improved liver biochemical parameters, attenuated hepatic steatosis, and partially restored oxidative stress indicators. Integrated multi-omics analyses indicated coordinated gut-associated metabolic and inflammatory responses to alcohol and intervention, rather than a single dominant pathway. These findings provide hypothesis-generating evidence; causality remains to be established. Overall, this study demonstrates a proof-of-concept, food-compatible lyophilized recombinant whole-cell catalyst that integrates enzymatic function with formulation stability and gastrointestinal resilience, highlighting an applied, food-compatible microbial framework for exploring alcohol-related metabolic stress. Full article

Agonists of the G protein-coupled receptor TGR5 have long been sought-after for their metabolic benefits. Intestinal TGR5 activation induces secretion of the antidiabetic hormone GLP-1, which can systemically improve diabetes phenotypes in multiple organs. However, no TGR5 agonist drug candidate has succeeded in clinical trials due to their low potency and unwanted side effects. A challenge in the field has been the development of TGR5 agonists that are non-toxic, long-acting, and have functional selectivity for G protein-biased agonism. In this study, we propose a systematic pipeline for engineering optimal TGR5 agonists with antidiabetic properties. This pipeline is interdisciplinary, combining in silico, in vitro, and in vivo assays to design and validate drug candidates. We identify 2 lead compounds that outline the necessary beneficial properties for a successful TGR5 agonist against diabetes. We uncover the molecular mechanisms that allow TGR5 agonists to induce the transcription of their target, TGR5, in intestinal enteroendocrine cells. Lastly, we investigate the molecular interactions of our lead candidates in the TGR5 binding pocket to identify optimal parameters for stability and biological activity. Our strategy for TGR5 agonist design and evaluation has the potential to guide the discovery process for targeted TGR5 therapeutics for metabolic diseases. Full article

Lactic acid bacteria (LAB) are pivotal microorganisms in the food industry. Current approaches for functional gene validation and trait improvement in LAB primarily rely on traditional gene editing and homologous recombination techniques. These methods are often cumbersome, inefficient, and time-consuming, hindering the rapid and precise customization of strains. This limitation has, to some extent, constrained the rapid selection and industrial application of functional LAB strains. The engineering of LAB through gene editing technologies has significantly advanced both fundamental and applied research. Among these, CRISPR/Cas gene editing has successfully achieved precise modification of multiple genes in various LAB species. Compared to conventional methods, it offers superior editing efficiency and lower operational costs, opening new avenues for functional gene identification and genetic improvement in LAB. However, the application of exogenous CRISPR/Cas systems in LAB faces technical challenges such as high off-target rates, chromosomal abnormalities, and cytotoxicity. The development of endogenous CRISPR/Cas-based editing tools for LAB provides novel pathways for precise regulation, rational design, and flexible application. This paper first outlines the structural components and mechanistic principles of CRISPR/Cas gene editing tools. It then explores the research progress and applications of both endogenous and exogenous CRISPR/Cas systems in LAB. Finally, it provides an outlook on the future application of CRISPR/Cas gene editing technology in LAB, offering a reference for its implementation in this field. The advent of gene editing technologies has significantly propelled functional gene validation and trait improvement in lactic acid bacteria (LAB), thereby advancing both fundamental research and industrial applications. Notably, the CRISPR/Cas system has emerged as a transformative tool enabling precise genetic modification in diverse LAB species, offering marked improvements in editing efficiency and cost reduction relative to conventional approaches. CRISPR/Cas-based editing strategies in LAB are broadly classified into exogenous and endogenous systems. Exogenous systems operate independently of the host’s native immune repertoire, conferring the advantages of broad strain applicability and high editing efficiency. These systems have been successfully deployed for functional gene characterization, metabolic pathway engineering, such as augmenting antimicrobial production, and probiotic safety enhancement via virulence gene deletion. Conversely, endogenous systems leverage the intrinsic CRISPR/Cas machinery of LAB, offering superior biocompatibility and minimized off-target risks. Notable applications include precise gene knockout and integration using the native Type I-E system in Lacticaseibacillus paracasei. This review provides a concise overview of CRISPR/Cas system architecture and mechanisms, followed by a systematic synthesis of research progress and applications for both exogenous and endogenous systems in LAB. Finally, future directions are outlined to guide the continued development and application of CRISPR/Cas technologies in this field. Full article

Plant-based biomaterials are increasingly recognized as bio-instructive platforms capable of actively modulating immune responses rather than functioning solely as passive structural supports. In this context, the term plant-based refers to photosynthetic biomass-derived platforms, including both terrestrial plants and marine macroalgae, reflecting their shared richness in polysaccharides and secondary metabolites relevant to immune engineering and regenerative medicine. This review critically synthesizes current evidence on plant-derived polysaccharides and phytochemicals, including algal sulfated polysaccharides (fucoidan, alginate, carrageenan, and ulvan), terrestrial plant polysaccharides (e.g., Lycium barbarum and Aloe vera derivatives), polyphenols, and other secondary metabolites such as terpenoids and alkaloids, highlighting their roles as immunomodulators in biomedical contexts. Key mechanisms include macrophage polarization along an M1–M2 continuum, pattern recognition receptor engagement, redox and metabolic regulation, and crosstalk between innate and adaptive immunity, with emphasis on context-dependent signaling and structural heterogeneity. Material design parameters, including molecular weight and chemical functionalization, are critical determinants of immune responses. Advanced delivery systems, such as hydrogels, nanocomposites, phytosomes, and plant-derived extracellular vesicles (EVs), enable improved stability and spatiotemporal control. Applications in wound and musculoskeletal regeneration are discussed alongside translational challenges, including variability, reproducibility, regulatory issues, and the need for standardized characterization and immune validation. Full article

2-Butanol is a promising biofuel due to its favorable properties and lower microbial toxicity compared to other butanol isomers. However, microbial production remains challenging due to the absence of a native biochemical pathway for directly converting sugars into 2-butanol. To achieve this goal, glucose should be directed through the 2,3-butanediol (2,3-BD) pathway, involving α-acetolactate synthase, α-acetolactate decarboxylase, and butanediol dehydrogenase for the formation of meso-2,3-BD, followed by diol dehydratase-catalyzed conversion of meso-2,3-BD to butanone and alcohol dehydrogenase-mediated reduction in butanone to 2-butanol. In this study, we report the development of six new recombinant strains based on Klebsiella pneumoniae G31, in which the metabolic pathway for converting glucose to meso-2,3-BD was extended to 2-butanol. All engineered strains harbored the vitamin B₁₂-dependent diol dehydratase complex (pduCDEGH) from Lentilactobacillus diolivorans DSM 14421 under its native promoter control. In addition, pduQ from the same strain, and adh from Clostridium beijerinckii DSM 51 encoding alcohol dehydrogenases were expressed under native, T7, or Ptac promoters. The highest yield of 2-butanol from glucose was achieved by K. pneumoniae K6 carrying the adh gene under the control of the T7 promoter—437 mg/L. Using 2-butanone as a substrate, K6 again produced the highest titer of 2-butanol (3.9 g/L), followed by the recombinant K8 (with adh under the Ptac promoter), and notably, by the native K. pneumoniae strains. Therefore, although pduQ encodes a key alcohol dehydrogenase in L. diolivorans, it has weaker properties than adh for the K. pneumoniae host in all promoter configurations. As the high expression levels of adh under T7 promoter control were driven by the native bacterial RNA polymerase, this promoter–host combination appears particularly suitable for developing other strains of industrial relevance. Full article

The microbial production of 1,5-pentanediol (1,5-PDO), a versatile platform chemical with extensive industrial applications, remains limited by suboptimal fermentation titers and incomplete understanding of metabolic bottlenecks. To address these challenges, this study employed comparative transcriptomics to systematically identify novel genetic targets capable of enhancing 1,5-PDO biosynthesis in engineered Escherichia coli. Transcriptomic profiling of the 1,5-PDO-producing strain relative to the parental E. coli W3110, conducted at both exponential (24 h) and stationary (96 h) growth phases, revealed 1384 significantly differentially expressed genes, including 851 upregulated and 533 downregulated genes. From these, 20 candidate metabolic genes associated with 1,5-PDO synthesis were selected for functional validation through plasmid-based overexpression or CRISPR interference (CRISPRi)-mediated repression. Reverse engineering confirmed that overexpression of fecA (encoding an iron(III)-citrate transporter) and deletion of gadA (encoding glutamate decarboxylase) significantly enhanced 1,5-PDO production. Subsequent chromosomal integration of fecA at the neutral ilvG locus and deletion of gadA generated the optimized strain S7, which achieved a 1,5-PDO titer of 1.7 g/L in shake flask cultures, representing a 13.3% increase over the parental strain, with a concomitant 50% improvement in glucose yield (0.18 mol/mol). In fed-batch fermentation at the 5 L bioreactor scale, strain S7 attained a titer of 12.45 g/L and a glucose yield of 0.26 mol/mol, marking a 15.6% enhancement in carbon conversion efficiency relative to the parental strain (0.225 mol/mol), while concurrently improving biomass accumulation by 7.6%. These findings demonstrate that transcriptomics-guided reverse engineering constitutes an effective strategy for elucidating nonobvious metabolic determinants and optimizing microbial cell factories for efficient 1,5-PDO production. The identification of fecA and gadA as beneficial targets provides valuable insights into the metabolic rewiring underlying enhanced 1,5-PDO biosynthesis and establishes a foundation for further strain improvement through systems metabolic engineering. Full article