Search Results (215)

Excessive ultraviolet A (UVA) irradiation disrupts extracellular matrix (ECM) homeostasis in skin photoaging by impairing the balance between synthesis and degradation, yet whether silk fibroin peptide (SF), a small bioactive peptide from Bombyx mori, can restore this balance through mechanotransduction pathways remains unknown. Herein, we demonstrate that SF dose-dependently rescues human dermal fibroblasts (HDFs) from UVA-induced oxidative stress, senescence, and ECM disintegration. Notably, SF not only suppresses reactive oxygen species (ROS) and restores activities of antioxidant enzymes, but is also associated with the recovery of the ITGB1-FAK mechanotransduction axis, as evidenced by restored fibronectin levels and increased focal adhesion kinase (FAK) phosphorylation, whereas integrin β1 (ITGB1) expression itself was not significantly altered. This mechanosensory recovery is accompanied by restoration of downstream transforming growth factor-β (TGF-β)/Smad signaling, upregulation of COL1A1, COL3A1 and ELN transcription, and simultaneous suppression of MMP1, MMP3 and MMP9. Unlike conventional antioxidants or exogenous collagen supplements that merely counteract oxidative damage or provide structural substitutes, SF may facilitate recovery of the disrupted cell–matrix interface potentially through modulation of integrin-mediated mechanochemical signal conversion, which may contribute to ECM homeostasis restoration. Collectively, SF promotes mechanotransduction, offering a potential paradigm for anti-aging strategies that target ECM homeostasis through integrin signaling. Full article

Silk fibroin (SF) derived from Bombyx mori cocoons was employed to fabricate gels using Ajisawa reagent (AJ) as the extraction medium. The resulting regenerated SF solution was subsequently directly dialyzed against an ethanol–water mixture, inducing a gradual and controllable solution–gel transition. Obtained SF gels exhibit a pronounced increase in compressive strength aligned with rising initial fibroin concentration, along with excellent water stability. FESEM, FTIR, and synchrotron X-ray diffraction analyses reveal a homogeneous network structure, likely governed by uniformly distributed physical silk II crosslinks. SF gels containing Ca²⁺ ions predominantly retain the silk I conformation, consistent with optical transparency and higher ionic conductivity. Mechanochromic SF-based gel was further developed through a one-step process involving pentacosadiynoic acid (PCDA) infiltration, followed by UV-induced polymerization into polydiacetylene (PDA), yielding a blue-colored gel. Upon compression, the PDA-infused gel exhibits a clear color transition from blue to red, demonstrating avid mechanochromic behavior. This system represents a promising platform for Structural Health Monitoring (SHM), owing to its intrinsic self-reporting capability and direct visual detectability, enabling the effective sensing of stress-induced damage and crack formation. Full article

Sericin-derived oligopeptides (SDOs) from the Bombyx mori yellow silk cocoons show strong bioactive properties. However, clinical safety data on SDOs produced by specific enzymatic hydrolysis with a particular serine-rich (20.5%) and aspartic acid-rich (16.9%) composition is required to obtain regulatory approval as a novel food ingredient. This Phase 0 randomized, double-blind, placebo-controlled trial evaluated the short-term safety, tolerability, and gut microbiota effects of SDOs supplementation in healthy adults. Forty-two healthy volunteers were randomized (1:1:1) to receive daily doses of placebo, 0.9 g SDOs or 1.8 g SDOs for eight weeks. Primary safety endpoints included vital signs, hematology, and comprehensive clinical chemistry (renal and hepatic functions). Secondary outcomes included lipid profiles, oxidative stress markers (hs-CRP, TAC, SOD, MDA) and gut microbiota composition analyzed by 16S rRNA metagenome sequencing. Forty-one participants (97.6%) completed the study with high compliance (>98%). No serious adverse events were reported. All primary clinical parameters remained within clinically normal ranges, and no significant differences between groups were observed throughout the study (p > 0.05). No adverse effects on fasting blood glucose, lipid profiles or systemic oxidative stress were observed after SDOs supplementation. Importantly, 16S rRNA sequencing analysis showed that SDOs maintained gut microbial homeostasis throughout the 8-week intervention period, with Bacteroidetes and Firmicutes as the predominant phyla in the core community structure. Oral intake of enzymatically generated SDOs up to 1.8 g/day in healthy adults was well-tolerated with only occasional mild and transient gastrointestinal symptoms that did not appear to be dose-dependent. These first preliminary findings suggest a favorable safety profile for this unique peptide preparation, supporting its potential evaluation as a novel food ingredient and providing a reasonable basis for future, larger-scale trials to evaluate its efficacy in metabolic health. Full article

The economic value of Bombyx mori is built on two complementary substrates: the productive traits and the molecular mechanism of fibroin synthesis. Despite their importance to European sericulture, neither phenotypic nor transcriptional characterizations of Romanian breeds have been reported. Herein, we combine ten phenotypic traits with qRT-PCR quantification of fibroin light-chain (Fib-l) and fibroin heavy-chain (FIBH) expression across four B. mori breeds: the Romanian breeds Băneasa 1 (B1) and Galben de Băneasa (GB), the Japanese breed JH3, and the Chinese breed Auriu Chinez (ACH). All breeds were reared on the same artificial diet under identical thermohydrometric conditions, highlighting the genetic background as the dominant source of variation. Phenotypically, univariate testing and multivariate analyses converged on a two-cluster solution, (B1 + JH3) and (GB + ACH), consistent with genetic background and silk-pigment. However, B1 is the only breed that combines high silk-gland mass with Fib-l overexpression relative to the other three breeds (FC = 2.7–3.6, all p < 1 × 10⁻⁴) and with a Fib-l/FIBH expression ratio of 9.27, above the 1.5–2.9 observed in the other three breeds. The molecular signature identifies B1 as transcriptionally distinct and provides a candidate mechanism for superior productive parameters under artificial-diet rearing. Full article

Deciphering the coloration mechanism of natural-colored cocoons in the domestic silkworm (Bombyx mori) is of great importance for the green and sustainable development of the sericulture industry. In this study, 14 silkworm strains were selected for studying differences in the coloration mechanism of diverse cocoon colors, and the present research carried out integrated investigations from three aspects: pigment content, differences in gene expression levels, and gene structural variation. The results demonstrated that pigment accumulation presented distinct tissue-specific and strain-specific characteristics. The middle silk gland (MSG) acts as the primary locus for pigment deposition: silkworm strains forming yellow or red cocoons accumulate carotenoids at high levels in this tissue, whereas those producing green cocoons show abundant flavonoid enrichment here. Analysis of gene expression profiles indicated that the expression patterns of core transporter genes are highly correlated with the spatial distribution of pigments. The expression level of CBP gene in the MSG is over 10-fold higher than that in the midgut (MG) among yellow/red cocoon strains. The pivotal glycosylation gene UGT86 displayed remarkably elevated expression in the MSG relative to other tissues across all green cocoon silkworm strains. The CBP gene acts as a core regulatory factor governing the transport of carotenoid pigments, and notable disparities existed in the coding region of the gene among silkworm strains with different cocoon colors. In contrast to yellow and red cocoon strains, the transcription start site of CBP gene is displaced in silkworm varieties that form green or white cocoons. In summary, this study clarified the expression patterns and variations in key pigment deposition-related genes at the population level for the first time and provided data references for the study of the biological basis and coloration mechanism of diverse cocoon colors. Full article

Biomaterials are engineered to interact with biological systems for therapeutic or diagnostic purposes. Among them, natural biomaterials offer important advantages over many synthetic polymers, including intrinsic biocompatibility, non-toxicity and biodegradability. Silk fibroin, a fibrous protein derived mainly from Bombyx mori cocoons, has re-emerged as a particularly versatile platform because it combines favourable mechanical, thermal, electrical and optical properties with aqueous processing and tuneable degradation. In this review, we first summarise the key structural, physicochemical and functional properties of regenerated silk fibroin, including its mechanical behaviour, thermal stability, dielectric and piezoelectric response, optical transparency and low autofluorescence. We then describe how extraction and regeneration protocols are used to produce defined material formats—fibres and nanofibrous mats, porous 3D scaffolds and hydrogels, sub-micron particles, thin films and microstructured devices—and outline major functionalisation strategies, ranging from physical blending and encapsulation to covalent chemistry, genetic engineering of recombinant silk variants, and enzyme-mediated conjugation approaches. Building on this foundation, we critically examine biomedical applications of silk fibroin with a particular emphasis on (i) hybrid silk–fluorophore systems for bioimaging and biosensing (nanodiamonds, quantum dots and organic dyes), (ii) optical fibre, wearable and edible sensors for health and food monitoring, (iii) wound dressings and wound-sensing platforms, and (iv) tissue engineering scaffolds and drug-delivery depots. Finally, we discuss current limitations, including process variability, the trade-offs introduced by blending and cross-linking, and the challenges posed by non-degradable inorganic fillers and clinical translation. Together, these perspectives highlight silk fibroin’s potential and constraints as a multifunctional biomaterial for next-generation biomedical devices and theranostic systems. Full article

Yellow silk cocoons of Bombyx mori provide two distinct bioactive classes: the carotenoid silk lutein (SL) and sericin-derived oligopeptides (SDOs). Their comparative efficacy and mechanisms in promoting cognitive health remain uncharacterized. This study compared the neuroprotective and cognitive-enhancing effects of SL and SDOs through chronic oral administration in two rodent models: an amyloid-beta (Aβ_25–35)-induced amnesia model in mice and a natural aging model in rats. Cognitive function was assessed using the Morris Water Maze (MWM) and Novel Object Recognition (NOR) tests, and underlying mechanisms were investigated via in vivo hippocampal long-term potentiation (LTP) and immunohistochemical analysis for apoptosis markers. Both SL and SDOs significantly ameliorated Aβ-induced deficits in recognition and spatial memory. Both substances enhanced spatial memory and LTP in old male rats in the natural aging paradigm, with efficacy comparable to that of donepezil (Don). This LTP-enhancing effect was sex-specific, being prominent in males but absent in aged females, although both sexes showed improved recognition memory. Critically, cognitive impairments in the Aβ model were not associated with significant neuronal apoptosis, and the protective effects appeared independent of anti-apoptotic pathways. In conclusion, SL and SDOs are potent cognitive-enhancing agents that mitigate memory deficits in acute neurotoxicity and chronic aging models. Their primary mechanism appears to be a robust enhancement of hippocampal synaptic plasticity rather than apoptosis prevention, positioning them as powerful synaptoprotective agents. These findings validate the potential to upcycle this agro-industrial byproduct into high-value nutraceuticals for promoting healthy brain aging. Full article

The silkworm, Bombyx mori (Bm), is an insect that contributes to industries such as silk production, cosmetics, medicine, and food, as well as to scientific research. A previous study showed that Bm odorant receptor (BmOr) genes, BmOr44, BmOr54, and BmOr63, may play a major role in oviposition. This research aimed to investigate the function of these three genes using a double-stranded RNA (dsRNA) technique to knock down their expression levels. Our results revealed that the gene-specific dsRNAs could moderately reduce the expression levels of BmOr44, BmOr54, and BmOr63 in the silk moth antenna. Silk moths were injected with 50 nM dsRNABmOr54 and 100 nM dsRNABmOr63 and showed relative oviposition rates under the mulberry leaves condition at 111.45% and 109.58%, respectively, when compared to those with dsRNAlacZ injection. The reduction in expression levels of these three genes showed no effect on the oviposition rates of the silk moths without mulberry leaves treatment. The expression levels of these BmOr genes were restored after fertilization, suggesting the temporary effects of the dsRNAs. Our findings suggested that variation in BmOr54 expression level was correlated with changes in oviposition behavior in Bombyx mori. Full article

The scientific community has addressed a wide range of research areas regarding the biotechnological potential of the silkworm silk gland of the Bombyx mori species. The silk gland has a remarkable capacity to synthesize two proteins, fibroin and sericin, each with a well-defined role. Recent research highlights fibroin as being used in the medical and pharmaceutical fields, with the possibility of expanding into nanotechnology. Sericin also has antibacterial, antioxidant, and moisturizing properties with use in the pharmaceutical and cosmetic industries. This paper highlights the importance of the two proteins synthesized by the silkworm silk gland of Bombyx mori by highlighting their structure, chemical composition, and properties. The utilization of the silk gland from a biotechnological perspective can facilitate remarkable progress in various fields of research, the most important of which would be the medical field. Full article

Adsorption is an effective method frequently used for removing contaminants, including dyes, from liquid effluents. This study uses silk fibroin nanoparticles produced by the Bombyx mori moth as an adsorbent material to remove methylene blue dye from aqueous solutions. Batch tests were carried out to examine the effect of pH and temperature on methylene blue adsorption and to obtain kinetic and equilibrium data. The experimental data were fitted to different kinetic models (pseudo-first-order, pseudo-second-order, Elovich, intraparticular diffusion and Bangham) and isotherm models (Langmuir, Freundlich, Sips and Redlich–Peterson). The experimental data can be best explained by the pseudo-second-order and Bangham kinetic models. The adsorption capacity increases with temperature so adsorption is an endothermic process. The maximum adsorption capacities achieved in the experiments were 122 mg·g⁻¹, 132 mg·g⁻¹, and 155 mg·g⁻¹ at temperatures of 10 °C, 25 °C, and 40 °C, respectively. Among the models studied, the ones that best describe the equilibrium data are Freundlich and Redlich–Peterson models. Full article

Pyriproxyfen, a juvenile hormone analog insecticide, poses severe risks to non-target silkworms (Bombyx mori), as evidenced by disrupted metamorphosis—a process strictly dependent on chitin synthesis and its precursor trehalose. However, the specific molecular interference of pyriproxyfen in these metabolic pathways remains unclear. This study investigated the transcriptional response of silkworm midguts to pyriproxyfen using RNA-Seq and validated spatiotemporal gene expression via qRT-PCR. By integrating transcriptomic data with long-term spatiotemporal profiling, we revealed novel tissue-specific expression dynamics. RNA-Seq identified 2059 differentially expressed genes, primarily enriched in metabolic pathways. Spatiotemporal analysis revealed that most chitin- and trehalose-related genes generally exhibited a biphasic “suppression–compensation” trend (initial downregulation followed by upregulation). Notably, tissue-specific responses were evident, with ChsA being continuously suppressed in the middle silk gland, which may be associated with impaired sericin secretion, while showing abnormal upregulation in the posterior silk gland. Additionally, trehalose metabolism genes (Treh and Tret) paralleled the fluctuation of chitin genes, indicating systemic metabolic reprogramming. These results suggest that the toxicity of pyriproxyfen is associated with a decoupling of trehalose metabolism from chitin synthesis and the induction of tissue-specific metabolic disorders. The tissue-specific, long-term spatiotemporal profiling of chitin and trehalose genes presented in this study fills a critical knowledge gap. This study characterizes the transcriptional profile associated with pyriproxyfen toxicity and provides a robust molecular reference for assessing its environmental risks to beneficial insects. Full article

Silk production is a classic example of a domestication trait, yet the cell-type-specific driver of its enhancement in the silkworm Bombyx mori remains unresolved. To address this, we integrated extensive bulk RNA-seq data with a single-nucleus RNA-seq atlas of silk glands (SGs) from domestic B. mori and wild B. mandarina for deconvolution analysis. This identified phenotype-associated cell subpopulations (Scissor+ and Scissor− cells) that enrich in B. mori and B. mandarina, respectively. Transcriptomic characterization revealed that B. mori SG cells exhibit a pervasive “pro-synthesis” transcriptional state, with concerted upregulation of silk protein genes and metabolic pathways. Conversely, B. mandarina cells maintained a “protective–adaptive” state, enriched for stress response and xenobiotic metabolism genes. Pseudotime analysis further delineated the cell state transitions, pinpointing key dynamic gene expression linked to high silk yield. Our findings demonstrate that domestication reshaped the silk gland cellular landscape, promoting a systemic shift toward a synthesis-optimized cell state. This study offers a new framework at the cellular level to elucidate the evolution of complex traits under selection. Full article

The silkworm (Bombyx mori) is essential to sericulture and is also becoming a key model organism in genomics and agriculture. For decades, genetic studies of the silkworm were limited by inefficient and inflexible genome tools. CRISPR genome editing allows precise and scalable alterations to genes regulating development, physiology, and industrial traits. This review summarizes silkworm genome-editing breakthroughs, highlighting CRISPR’s evolution from simple gene knockouts to large-scale genome-wide screening. We highlight how these advancements contribute to disease resistance, higher yields, and the development of new silk-based materials, as well as how they influence the development and growth rate of the sericulture. The creation of high-quality reference genomes, pangenomes, and genome-wide screening systems has made the silkworm a major model for integrating multiple biological datasets and approaches, such as genomic, transcriptomic, and proteomic. By considering the unique biological characteristics of the silkworm, this provides new insights for research on silk biology, piRNA synthetic biology, and hormonal signaling regulation. Finally, we examine new areas at the intersection of CRISPR, pangenomics, and artificial intelligence (AI) and suggest future paths for molecular breeding, pest control, and synthetic biology. Moreover, AI-assisted prediction of CRISPR outcomes is utilized to inform the design of targeted trait modifications, representing an approach to enhancing biomanufacturing efficiency and eco-friendly silk production. Together, these advances have made the silkworm a flexible genetic platform and an important part of sustainable agriculture and biomanufacturing. Full article

Understanding the genetic basis of growth and moltism in silkworm (Bombyx mori) is essential for improving silk production efficiency and elucidating the mechanisms underlying developmental plasticity. Thus, this study aimed to establish a collection of 20 representative B. mori core strains and perform integrative genomic analyses combining genome-wide association studies (GWASs) and population-specific variant detection. A total of 5,293,831 high-confidence single-nucleotide variants (SNVs) were identified across the population, and GWAS revealed significant associations between specific genetic loci and four growth-related traits: larval weight at day 7 of the fifth instar, pupal weight, cocoon weight, and cocoon layer weight. Among these, two missense variants within the Cycb gene were significantly correlated with increased body weight at the late fifth instar stage, suggesting a potential role for this isoform in regulating cell-cycle-driven tissue expansion during rapid larval growth. Moreover, a population-based comparison identified 2803 trimolter-specific missense SNVs in 1440 genes, of which 109 were functionally annotated. Notably, homozygous variants were detected in key developmental regulators, such as MET1 and TOR1, implying potential alterations in juvenile hormone signaling and nutrient-dependent growth pathways that may contribute to the dominant trimolter phenotype. Although experimental validation remains necessary, these findings provide a genomic framework for understanding the molecular mechanisms underlying moltism variation and offer valuable resources for future silkworm genetic improvement. Full article

This study evaluated the effects of incorporating silk fibroin nanoparticles into self-curing polymethyl methacrylate (PMMA) on the mechanical and Candida albicans responses of provisional dental prostheses. Rectangular specimens (64 × 10 × 3 mm) were fabricated and assigned to three groups (n = 10): G1 (control), PMMA without reinforcement; G2, PMMA with 0.5% silk nanoparticles; and G3, PMMA with 1% silk nanoparticleScheme4. 4 × 6 mm) were prepared. Scanning electron microscopy (SEM) was used to assess nanoparticle incorporation within the polymer matrix. No significant differences were observed in surface roughness (G1 = 0.4118 ± 0.100; G2 = 0.3245 ± 0.072; G3 = 0.3269 ± 0.076) or microhardness (G1 = 12.21 ± 0.351; G2 = 12.72 ± 0.213; G3 = 12.53 ± 0.177). Flexural strength differed significantly among the groups (p = 0.009), with higher values in nanoparticle-reinforced specimens (G1 = 79.142 ± 3.202; G2 = 87.089 ± 2.756; G3 = 92.412 ± 1.963). None of the tested concentrations exhibited antifungal activity against C. albicans. In conclusion, the incorporation of silk fibroin nanoparticles enhanced the flexural strength of self-curing PMMA without adversely affecting surface roughness or microhardness, although no antifungal effect was detected at the evaluated concentrations. Full article