Severe nitrogen (N) deficiency inhibits crop growth and yield, while low use efficiency of N fertilizer causes resource waste and environmental harm. Enhancing crop N use efficiency (NUE) is thus a critical scientific challenge. Ecofriendly and cost-effective silicon (Si) fertilizer can enhance NUE across the entire soil-plant continuum. Si-mediated improvements in soil physicochemical properties and microbial community structure underlie enhanced mineralization and suppressed denitrification. Si-cell wall interactions support symbiont recognition, nodule initiation, and formation of functional nodules for sustained N2 fixation. Si also upregulates genes encoding N transporters and assimilatory enzymes to improve N uptake, assimilation, and remobilization. This mini-review synthesizes Si's roles in regulating soil N transformation and plant N uptake, assimilation, and remobilization. It aims to support precision Si fertilization strategies that reduce synthetic N input without compromising yield.

Aortic dissection (AD) is a severe vascular condition marked by abrupt onset, rapid progression, and heightened mortality rates. Vascular smooth muscle cells (VSMCs), the predominant cellular component of the arterial media, are essential for maintaining the structural integrity and functionality of blood vessels. Recent studies have associated Cysteine-rich protein 2 (CSRP2) with the advancement of several vascular diseases. The involvement of CSRP2 in AD progression is unclear. Aortic tissues were collected from patients for RNA sequencing and histological analysis. A mouse model of AD was created using β-aminopropionitrile monofumarate (BAPN), while VSMC phenotypic switching was induced by platelet-derived growth factor BB (PDGF-BB). Adeno-associated virus vector was used to overexpress CSRP2 in aorta. A variety of histopathological assays and biochemical analyses were applied to determine gene and protein expression patterns as well as uncover underlying molecular mechanisms. CSRP2 was significantly downregulated in both human and murine AD, and CSRP2 gene overexpression dramatically reduced BAPN-induced AD incidence and prevented animal mortality. CSRP2 could preserve a contractile VSMC phenotype, even though under PDGF-BB stimulation. Mechanistically, our findings reveal that CSRP2 directly interacts with p130 Crk-associated substrate (p130Cas; also known as BCAR1) and reduces its phosphorylation, which in turn inhibits the activation of extracellular signal-regulated kinase (ERK) signaling pathways, thereby preventing VSMC phenotypic switching induced by PDGF-BB. Our findings identify CSRP2 as a novel regulator of VSMC phenotypic modulation and a significant modulator of AD development, suggesting its potential as a target for early intervention for AD.

Structural variants (SVs) are a major yet underused source of adaptive variation in aquaculture. We built a genome-wide SV atlas for 180 Penaeus vannamei from six commercial breeding populations and discovered 1,159,046 SVs, with uneven chromosomal distributions and multi-type hotspots. Over 63.53% of SVs overlapped repeats-especially simple sequence repeats, DNA transposons, and LINEs. SV and SNP densities were highly correlated. Across populations, 482 k SVs were shared and 145,623 were singletons; the fraction of deletions increased from shared to singleton classes. BMK and KH harbored more singletons than SIS, RH, and CP, indicating greater divergence. PCA and ADMIXTURE recovered three major clusters and revealed the substructure in RH, mirroring SNP analyses. Selection scans identified 78-193 sweep windows per population encompassing 38-161 candidate genes. These genes were predominantly enriched in population-specific processes such as chromatin regulation, meiotic recombination, membrane-associated functions, suggesting that structural variants may contribute to divergence in reproductive, metabolic, and structural pathways across breeding programs. Nevertheless, 10 genes showed parallel signals in over 3 populations; many carry short deletions likely affecting regulatory or coding elements. Together, these results show that genome architecture and domestication jointly shape the shrimp SV landscape; that SVs alone robustly resolve population history; and that a small set of recurrent, deletion-bearing regulatory genes may underpin convergent improvement. The SV map and candidate loci provide diagnostic markers for germplasm tracing and candidate loci for marker-assisted or genomic selection in P. vannamei breeding.

Objective To establish an efficient and rapid primary culture protocol for mouse pulmonary artery smooth muscle cell (PASMC). Methods PASMC were isolated from mice using a novel dual-enzyme digestion method. Cell morphology was observed under an inverted phase-contrast microscope, and cell type and purity were identified by immunofluorescence staining for α-smooth muscle actin (α-SMA). Cell growth after passage was assessed using the CCK-8 assay. The migratory response of PASMC to platelet-derived growth factor-BB (PDGF-BB) was evaluated by cell scratch assay. Changes of protein expression in primary PASMC after stimulation of transforming growth factor β1 (TGF-β1) were detected by Western blot. Results Under light microscopy, PASMC showed a long spindle-shaped morphology with a positive rate reaching as high as 98%. The growth curve of passaged cells approximated an "S" shape. Primary cultured PASMC showed a significant migratory response to stimulation of PDGF-BB. TGF-β1 stimulation significantly increased the expression of phospho-Smad2 (p-Smad2) in PASMC. Conclusion The novel dual-enzyme digestion method significantly improves the isolation efficiency and viability of primary PASMC, providing a sufficient and phenotypically stable source of high-quality cells for in vitro studies.

The C. elegans SIK3 homolog KIN-29 regulates the interaction between sleep and metabolism, but mechanisms underlying this regulation are not understood. Here, we show that KIN-29 regulates sleep that is induced by cellular stress (stress-induced sleep or SIS) through mitochondrial reactive oxygen species (ROS) signaling. Following sleep-promoting ultraviolet-C (UVC) irradiation, mitochondrial ROS rises in concert with sleep in wild-type but not in sleepless kin-29 mutants. kin-29 mutants have reduced mitochondrial ROS, reduced oxygen consumption rates, and are resistant to oxidative stress. Transcriptomic and proteomic profiling of kin-29 mutants reveal enrichment for genes involved in ROS mitigation such as the mitochondrial superoxide dismutase SOD-3. Consistent with the notion that ROS promotes sleep, genetic disruption of mitochondrial SODs enhances UVC-induced SIS. Increasing mitochondrial ROS using the optogenetic tool SuperNova partially restores SIS in kin-29 mutants but not in mutants with defective function of the sleep-inducing ALA neuron; this suggests that mitochondrial ROS act downstream of kin-29 but upstream of ALA. The identification of mitochondrial ROS as a nematode sleep regulator supports a phylogenetically conserved mechanism by which metabolic stress and SIKs promote sleep.

Rheumatoid arthritis (RA) is characterized by chronic synovial inflammation accompanied by pathological angiogenesis, which contributes to pannus formation and disease progression. However, the upstream mechanisms regulating pathological angiogenesis in RA remain incompletely understood. In this study, bioinformatic analysis of two independent Gene Expression Omnibus (GEO) datasets, immunohistochemical analysis of human synovial tissues, and functional studies using MH7A synovial fibroblasts and HUVEC tube formation assays were performed to investigate the role of WNT1-inducible signaling pathway protein 3 (WISP-3) in RA angiogenesis. WISP-3 expression was consistently elevated in RA synovial tissues compared with healthy controls. Recombinant WISP-3 significantly enhanced endothelial tube formation and increased platelet-derived growth factor-B (PDGF-B) expression in MH7A cells. Mechanistically, WISP-3 activated the PI3K/p85/Akt/mTOR signaling pathway, whereas pharmacological inhibition or siRNA-mediated knockdown of p85, Akt, or mTOR markedly attenuated PDGF-B expression and angiogenic activity. WISP-3 also suppressed hsa-let-7b-5p expression, and restoration of hsa-let-7b-5p using a synthetic mimic significantly reduced WISP-3-induced PDGF-B expression and endothelial tube formation. Luciferase reporter assays further confirmed PDGF-B as a direct target of hsa-let-7b-5p. These findings identify a previously unrecognized WISP-3/p85/Akt/mTOR/hsa-let-7b-5p/PDGF-B signaling axis that promotes pathological angiogenesis and provides new mechanistic insight into synovial vascular remodeling in RA.

Decorin, a proteoglycan shown to inhibit transforming growth factor β1 (TGF-β1) signaling, has been increasingly considered as a potential anti-fibrotic agent to aid in therapies addressing corneal scarring and blindness. Decorin is also known to interact with a wide range of other growth factors, such as platelet-derived growth factor (PDGF), which has been shown to stimulate corneal cell migration to repopulate the decellularized region of the wounded cornea. In other tissues, decorin has been shown to inhibit PDGF-mediated migration and prolong wound healing. However, our understanding of the effect of decorin on PDGF signaling in the corneal stroma environment is limited. Specifically, thus far, there have been no studies investigating the interaction between decorin and PDGF in the context of the uniquely organized fibrillar collagen extracellular matrix (ECM), which provides topographic cues that guide cell migration during wound healing. The purpose of this study is to use an in vitro model of decorin-coated aligned collagen fibrils analogous to the corneal stroma ECM to investigate this interaction. With this in vitro model, we demonstrate that decorin inhibits the response of PDGF-BB-stimulated keratocytes to a 2-dimensional (2D) aligned collagen fibril ECM, reducing cell alignment, motility, PDGF receptor β (PDGFRβ) phosphorylation, and wound closure. We observed that when presented with a decellularized wound region, cells on the decorin-coated substrates migrated more randomly and were less aligned with the underlying aligned collagen fibrils than cells on uncoated fibrils, resulting in slower wound closure. Furthermore, PDGF-BB-stimulated cells on the decorin coating had increased branching and reduced solidity, representing a shift from the elongated, bipolar morphology typically resulting from PDGF-BB treatment towards the stellate, branched keratocyte phenotype. While decorin seems to be an effective agent against TGF-β1-mediated fibrosis, its interaction with PDGF-BB appears to present other challenges to wound healing that should be considered in the development of therapies for healthy corneal wound healing.

While glucose-driven mitochondrial dysfunction has been proposed to promote vascular dysfunction responsible for saphenous vein graft failure (VGF) following bypass surgery, the impact of type 2 diabetes mellitus (T2DM) on mitochondrial function in human saphenous vein smooth muscle cells (HSVSMCs) responsible for maladaptive remodelling is unknown. Our aim was to identify signalling pathways that mediate any mitochondrial dysfunction in HSVSMCs in vitro and assess the impact of T2DM. HSVSMCs explanted from surplus HSV tissues from consenting T2DM and non-diabetic patients undergoing coronary artery bypass graft surgery were treated with known activators and inhibitors of the JAK/STAT and MAPK/ERK pathways. Following this, real-time oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) measures of mitochondrial function were then determined. Our findings revealed that both IL-6/sIL-6Rα trans-signalling complexes and platelet-derived growth factor-BB (PDGF-BB) significantly increased OCR in HSVSMCs from T2DM patients but not non-diabetic controls. Meanwhile, only PDGF-BB increased ECAR in HSVSMCs from T2DM patients but not in non-diabetic controls. The observed increases in OCR and ECAR were abolished by JAK1/2-selective inhibitor ruxolitinib. Furthermore, thrombin caused a significant increase in OCR, specifically in HSVSMCs from T2DM patients, and this effect was abolished by the MEK1/2-selective inhibitor trametinib. Both ruxolitinib and trametinib significantly reduced basal OCR and ECAR in HSVSMCs from both T2DM and non-diabetic patients. Together, these findings demonstrate a JAK/STAT- and MAPK/ERK-mediated regulation of mitochondrial function in HSVSMCs. As such, they represent potential targets for regulation of HSVSMC function that can be explored for drug development to limit saphenous VGF in T2DM.

Platelet-derived growth factor subunit B (PDGF-B) signaling plays a critical role in pericyte activation and neurovascular repair following ischemic injury. Although enhancing PDGF-B signaling in pericytes represents a promising therapeutic strategy for ischemic stroke, practical approaches have not yet been developed. In this study, we evaluated the therapeutic efficacy and underlying mechanisms of PDGF-B-modified heat shock protein nanoparticles (PDGF-B HSPNPs) in a transient middle cerebral artery occlusion mouse model of either sex. Mice were treated with single intravenous injection of PDGF-B HSPNPs immediately after reperfusion, and infarct volume and motor function were assessed. To investigate cellular effects, flow cytometric analysis of brain-derived single-cell suspensions was performed 3 d after treatment to quantify platelet-derived growth factor receptor β-positive pericytes. Our results demonstrate that PDGF-B HSPNPs administration significantly reduced infarct volume and improved motor function, accompanied by enhanced activation of pericytes in the peri-infarct region. These findings suggest that PDGF-B HSPNPs represent a promising therapeutic approach for the treatment of ischemic stroke.

From an ecological perspective, many animals, particularly birdstext, are exposed to increasing stress levels in the context of the current climate crisis. Therefore, the development of tools that can reliably measure long-term stress exposure in animals is fundamental. Epigenetic mechanisms offer a promising approach, as stress during early development can alter DNA methylation in peripheral cells, such as avian red blood cells (RBCs). Here, we investigated whether distinct early-life environments leave specific epigenetic marks in RBCs, as well as the persistence of these marks. Male chickens were exposed from day 4 to 3.5 weeks of age to either social isolation stress (SIS), environmental enrichment or control barren conditions. RBCs were collected immediately after exposure and after six months. We found that, with age, SIS increased the number of hypermethylated regions, while enrichment induced mostly hypomethylated regions and fewer overall methylation changes. The control group showed a balanced mix of hyper- and hypomethylated regions. Pathway analysis revealed that differentially methylated region (DMR)-associated genes in SIS were enriched for immune-metabolic pathways, while those in the enrichment group were linked to microRNA regulation and nuclear receptor signalling. Therefore, we show that differing early-life environmental conditions leave persistent and distinct epigenetic signatures in RBCs, with potentially different functional consequences. This article is part of the theme issue 'Ecological epigenetics at the intersection of behaviour and life history variation in non-model animals'.

Angiogenesis, the growth of vasculature from existing blood vessels, requires the coordinated secretion of multiple angiogenic growth factors that each stimulate the cellular recruitment, patterning, and morphogenesis inherent to vascular network formation. Among these secreted factors, vascular endothelial growth factor (VEGF), fibroblast growth factor-2 (FGF-2), and platelet derived growth factor (PDGF) amplify key stages of angiogenesis. Disruptions in their secretion have been implicated in poor vascular network formation. Current methods for exploring variations in the phased presentation of multiple different proteins are limited, which has restricted our ability to explore the effect of growth factor timing on angiogenesis. To address this knowledge gap, we developed affibodies, which are alpha-helical binding proteins, to phase the release of VEGF-165, FGF-2, and PDGF-BB from a single delivery vehicle via specific protein-affibody affinity interactions. We used yeast surface display to engineer three VEGF-, three FGF-2-, and two PDGF-specific affibodies with a wide range of affinities for their target proteins spanning dissociation constants of 3.08 ± 0.21 nM to 4550 ± 590 nM. We demonstrated that the cumulative release of VEGF and FGF-2 is inversely correlated with the strength of the protein-affibody affinity interaction and that hydrogels containing multiple protein-specific affibodies can control the release of VEGF, FGF-2, and PDGF, largely in accordance with the strength of the affinity interactions. Using a rat-derived intact microvascular fragment (MVF) model of in vitro angiogenesis, we revealed that sequential delivery of soluble VEGF, followed by FGF-2, and then PDGF enhances vascular network length by 2.8-fold and branching by 4.1-fold compared to untreated MVFs. We then designed an affibody-conjugated polyethylene glycol maleimide (PEG-MAL) hydrogel to mimic this sequence of protein delivery, resulting in a 3.0-fold increase in vascular network length and a 2.3-fold increase in vascular branching compared to all other hydrogel compositions and the sequential delivery of soluble growth factors. Changing temporal growth factor presentation with affibody-conjugated hydrogels altered the expression of key angiogenic genes involved in vessel stabilization and destabilization and matrix remodeling. Perivascular coverage measured by the colocalization of lectin and alpha smooth muscle actin staining was similar between all treatment groups, suggesting pericyte recruitment to stabilize expanded vascular networks created by the soluble and affibody-mediated delivery of the optimal sequence of proteins. Overall, this work establishes a new biomaterial platform for modulating the timing of growth factor delivery, enabling the exploration of how temporal variations in protein secretion impact regeneration and development.

Goals in plastic surgery and aesthetic medicine include minimizing healing complications, optimize aesthetic outcomes and improve patient satisfaction. Platelet-derived growth factor BB (PDGF-BB) is among the most potent natural activators of healing. A pharmaceutical copy of natural PDGF-BB, (rhPDGF-BB or pure PDGF) is the active ingredient in four US Food and Drug Administration-approved therapies to stimulate healing of skin, mucosa, gingivae or bone. Here we describe the mechanism of action and clinical uses of off-the-shelf pure PDGF in plastic surgery and aesthetic medicine as a post-treatment adjunct to enhance patient satisfaction.