Biomedical subjects

Shuo Yang

Publications and source records attributed to Shuo Yang.

11 recordsLinked to original sources

PubMed2026

Decoding mechanoregulation in immunological synapses using biomimetic artificial cells.

Mechanical force-driven signaling has emerged as a key regulator of cell-cell interactions (CCIs), which can enhance immune cell function. However, current biochemical approaches for studying CCIs offer minimal direct control over cellular bulk phenotypes, while synthetic biomaterial systems fail to mimic the dynamic complexity of cells. Here we introduce kpiCells, a biomaterial-based platform that uses a biomimetic membrane-endoplasmic architecture to enable finely tuned phenocopying of cellular states via modular mechanical, chemical and topographical inputs. We demonstrate that kpiCells can engage in physiological CCIs and reproduce critical subcellular features. In T cell systems, kpiCells enable integrated interrogation of afferent mechanosensing pathways and efferent force-exertion pathways, and support measurement of piconewton-scale forces at individual T cell antigen receptors as well as single cell-cell force fingerprints that define activation thresholds. This work establishes kpiCells as a bionic model that enables synthetic material design with the level of functional complexity approaching living cell systems.

Artificial Cells↗

PubMed2026

Emergence of cefiderocol resistance in carbapenem-resistant Escherichia coli ST167 prior to clinical use: A multifactored resistance landscape.

OBJECTIVES: Cefiderocol is a novel siderophore cephalosporin with potent activity against multidrug-resistant Gram-negative bacteria. Here, we reported the prevalence and mechanisms of cefiderocol resistance in carbapenem-resistant Escherichia coli (CREC) in China before its clinical use. METHODS: A total of 443 non-duplicate CREC isolates collected from 67 hospitals in China (2013-2021) underwent antimicrobial susceptibility testing according to CLSI guidelines. Whole-genome sequencing, transcriptomic analysis, siderophore quantification, and targeted genetic manipulation were performed to investigate the underlying resistance mechanisms. RESULTS: Among the 443 CREC isolates, 102 (23.0%) were resistant to cefiderocol, and 34 (7.6%) showed intermediate susceptibility. Multivariable logistic regression identified ST167 lineage (OR, 3.05; 95% CI, 1.12-8.29; P = 0.028), blaNDM-5 carriage (OR, 9.04; 95% CI, 2.96-27.57; P < 0.001), and cirA truncation (OR, 49.56; 95% CI, 20.33-120.79; P < 0.001) as independent factors associated with cefiderocol resistance. Among ST167 isolates, cefiderocol-resistant isolates showed increased yersiniabactin carriage and siderophore production but comparable TonB-dependent transporter expression profiles. Phylogenetic analysis revealed that cefiderocol-resistant ST167 isolates clustered into a distinct subclade enriched with resistance-associated determinants, including a recurrent FhuA P50S substitution detected in 59/64 (92.2%) resistant isolates. Functional assays showed that the P50S substitution increased cefiderocol minimum inhibitory concentration (0.032-0.125 µg/mL), particularly in an NDM-5-producing background (0.032-0.5 µg/mL). CONCLUSIONS: Cefiderocol resistance is highly prevalent among high-risk ST167 CREC isolates before the clinical introduction of cefiderocol in China, highlighting the need for continued surveillance of this epidemic lineage. Cefiderocol resistance is mediated by multiple resistance determinants, and we identify the recurrent FhuA P50S substitution as a novel contributor to reduced cefiderocol susceptibility.

Antimicrobial resistance↗

PubMed2026

Epigenetic safety of in vitro maturation in PCOS: genome-wide DNA methylation profiling of cord blood from a randomized controlled trial.

BACKGROUND: In vitro maturation (IVM) provides a safer alternative to conventional in vitro fertilization (IVF) for women with polycystic ovary syndrome (PCOS) by mitigating the risk of ovarian hyperstimulation. However, concerns persist regarding whether IVM perturbs epigenetic reprogramming in the offspring. Current evidence is constrained by candidate-gene approaches or a lack of parental controls. This study aimed to evaluate the genome-wide DNA methylation safety of IVM compared with conventional IVF using a rigorous trio-based design. METHODS: This secondary epigenetic analysis was nested within a randomized controlled trial (RCT) (ClinicalTrials.gov: NCT03463772). We included 10 nuclear families (trios), comprising five IVM-conceived and five IVF-conceived singleton offspring alongside their biological parents. Both groups utilized a uniform freeze-only single-blastocyst transfer strategy to minimize hormonal confounding. Genomic DNA from umbilical cord blood (UCB) and parental peripheral blood was analyzed using reduced representation bisulfite sequencing (RRBS). Genome-wide methylation patterns and differentially methylated regions (DMRs) were subsequently compared between the groups. RESULTS: Clinical characteristics were comparable between the IVM and IVF groups. Genome-wide analyses demonstrated high concordance in UCB methylation patterns, revealing no significant differences in global CpG methylation levels or distributions across key genomic features (promoters, CpG islands, and gene bodies). Only three rare DMRs were identified in UCB (representing ~ 0.0001% of the genome), none of which mapped to imprinted or developmentally critical loci. Furthermore, methylation variability remained consistent between the groups. CONCLUSIONS: Our findings provide robust mechanistic evidence supporting the epigenetic safety of IVM. The remarkable stability of the neonatal methylome confirms that specific IVM conditions do not compromise early developmental programming, thereby endorsing IVM as a safe and viable alternative for women with PCOS. TRIAL REGISTRATION: ClinicalTrials.gov registry, NCT03463772. Registered on March 13, 2018.

Humans↗

PubMed2026

Enzymatic innovations in Angelica pubescens reveal dual coumarin biosynthetic pathways driving metabolic diversification.

Coumarins are structurally diverse phenylpropanoid derivatives with ecological and pharmacological significance, yet the biosynthetic logic underlying their diversification remains incompletely understood in non-model medicinal plants. Angelica pubescens (Apiaceae), widely used in traditional Chinese medicine, accumulates a rich repertoire of furanocoumarins and dihydrofuranocoumarins, making it an ideal system to investigate this metabolic complexity. Here, we combined chromosome-level genome assembly, transcriptome and metabolite profiling, phylogenetics, and heterologous expression assays to dissect coumarin biosynthesis in A. pubescens. We identified two functionally specialized O-methyltransferases, ApOMT1 and ApOMT2, which catalyze regioselective methylation of xanthotoxol and bergaptol to yield the furanocoumarins xanthotoxin and bergapten. We also characterized ApCYP736A121, a cytochrome P450 enzyme that converts osthenol to the dihydrofuranocoumarin columbianetin via a previously unknown mechanism. Gene expression and metabolite accumulation patterns across tissues and developmental stages revealed functional partitioning among pathway branches. Phylogenetic and syntenic analyses indicated that ApOMT1 and ApOMT2 arose through subfunctionalization following gene duplication, whereas ApCYP736A121 evolved via neofunctionalization from a distantly related CYP736 ancestor. Together, our findings uncover dual biosynthetic routes to structurally distinct coumarins in A. pubescens and provide insights into the evolutionary mechanisms contributing to metabolic innovation in Apiaceae. This work lays a foundation for future efforts to engineer coumarin pathways and understand their ecological functions in medicinal plants.

Coumarins↗

PubMed2025

Targeting phagocytosis for amyloid-β clearance: implications of morphology remodeling and microglia activation probed by bifunctional chimaeras.

Amyloid-β (Aβ), a key driver of Alzheimer's disease (AD) pathogenesis, possesses diverse harmful and clearance-resistant structures that present substantial challenges to therapeutic development. Here, we demonstrate that modulating Aβ morphology, rather than Toll-like receptor 2 (TLR2)-dependent microglia activation, is essential for effective phagocytosis of Aβ species by microglia. By developing a bifunctional mechanistic probe (P2CSKn) designed to remodel Aβ and activate TLR2, we show it restructures soluble Aβ (sAβ) and fibrillar Aβ (fAβ) into less toxic hybrid aggregates (hPAβ). Critically, this structural remodeling protects microglia from Aβ toxicity while enabling robust phagocytosis. Moreover, although TLR2 activation mildly enhances Aβ uptake, it concurrently triggers detrimental inflammation that negates its benefits. Our findings establish morphological remodeling as the critical determinant of effective Aβ clearance and suggest a morphology-focused strategy for developing safe therapeutics for Aβ-related diseases.

Microglia↗

PubMed2006

Inhibition of wild-type p66ShcA in mesangial cells prevents glycooxidant-dependent FOXO3a regulation and promotes the survival phenotype.

Hyperglycemia triggers an exponential increase in reactive oxygen species (ROS) at the cellular level. Here, we demonstrate induction of the oxidant-resistant phenotype in mesangial cells by silencing the wild-type (WT) p66ShcA gene. Two approaches were employed to inhibit WTp66ShcA in SV40 murine mesangial cells and normal human mesangial cells: transient transfection with isoform-specific p66ShcA short-intervening RNA and stable transfection with mutant 36 p66ShcA expression vector. At high ambient glucose (HG), p66ShcA-deficient cells exhibit resistance to HG-induced ROS generation and attenuation in the amplitude of the kinetic curves for intracellular ROS metabolism, indicative of the pivotal role of WTp66ShcA in the generation of HG oxidant stress. We next examined phosphorylation and subcellular distribution of FKHRL1 (FOXO3a), a potent stress response regulator and downstream target of WTp66ShcA redox function. At HG, cell extracts of p66ShcA-deficient cells analyzed by immunoblotting show attenuation of FOXO3a phosphorylation at Thr-32, and indirect immunofluorescence of p66ShcA-deficient cells, cotransfected with HA-FOXO3a, show predominant HA-FOXO3a nuclear localization. Conversely, parental cells at HG show upregulation of phos-Thr-32 and nuclear export of HA-FOXO3a. To determine whether inhibition of cross talk between WTp66ShcA and FOXO3a confers protection against oxidant-induced DNA damage, DNA strand breaks (DSB) and apoptosis were examined. At HG, p66ShcA-deficient cells exhibit increased resistance to DSB and apoptosis, while parental cells show a striking increase in both parameters. We conclude that knockdown of WTp66ShcA redox function prevents HG-dependent FOXO3a regulation and promotes the survival phenotype.

Adaptor Proteins, Signal Transducing↗

PubMed2006

Apomorphine-induced activation of dopamine receptors modulates FGF-2 expression in astrocytic cultures and promotes survival of dopaminergic neurons.

Apomorphine (APO), a potent D1/D2 dopamine receptor agonist, is currently used as an antiparkinsonian drug. We have shown previously that APO stimulates synthesis and release of multiple trophic factors, such as brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF), in both mesencephalic and striatal neurons, thereby effectively preventing dopaminergic neuron loss in vitro. The present study was designed to investigate the effects of APO on fibroblast growth factor-2 (FGF-2) expression and regulation in astrocytes, and furthermore, to identify signaling mechanisms underlying these effects. Here, we show that FGF-2 expression is robustly induced in cultured astrocytes in response to APO. FGF-2 expression was proportional to APO concentration and time-dependent. Conversely, treatment with S-APO, a derivative of R-APO lacking DA receptor agonist activity, did not alter FGF-2 levels. APO treatment resulted in enhanced cytosol FGF-2 immunoreactivity, export of high MW forms of FGF-2 to the cytoplasm from the nucleus and increased extracellular release of FGF-2. Interestingly, both high and low MW forms of FGF-2 were detectable in conditioned medium of APO-treated cultures. This APO-induced effect was correlated with activation of D1 and D2 receptors, as it could be either mimicked by dopamine receptor agonists (SKF38393, quinpirole) or partially blocked by antagonists (SCH23390, SKF83566, haloperidol). Activation of the D1 receptor preferentially increased PKA activity, whereas activation of the D2 receptor only promoted phosphorylation of MAPK. Importantly, APO-modulated FGF-2 expression was independent of Akt/phosphoinositide 3-kinase signaling. These data suggest that APO can enhance biosynthesis and release of FGF-2 through activation of dopamine receptors in striatal astrocytes. Both cAMP/PKA and MEK/MAPK signaling cascades are major steps mediating this process.

Animals↗

PubMed2006

Expression of trophinin and bystin identifies distinct cell types in the germinal zones of adult rat brain.

In the adult brain, the subventricular zone (SVZ) is one of the regions where active neurogenesis occurs. Relatively few specific markers are available to distinguish different types of cells in the SVZ and rostral migratory stream (RMS) of adult brain. Here, we showed that trophinin and bystin, both of which are required for early embryo implantation during development, were expressed in the SVZ and RMS of the adult rat brain, but not in the brain of embryos and early postnatal animals. Trophinin-expressing cells were immunopositive for both Ki-67 and nestin in the SVZ. Some of the trophinin-positive cells did not express either the type A cell marker polysialylated weakly adhesive form of the neural cell adhesion molecule (PSA-NCAM) or the type B cell marker glial fibrillary acidic protein (GFAP). Double-label immunohistochemistry revealed that bystin-positive cells co-expressed GFAP, Ki-67 and nestin, but not PSA-NCAM, suggesting that they are likely type B cells. Intracerebroventricular infusion of cytosine-beta-d-arabiofuranoside (Ara-C) eliminated trophinin-positive cells in the SVZ. Following its depletion, however, the remaining bystin-positive cells continued to divide and generate actively dividing trophinin-positive cells that were negative for PSA-NCAM, leading to reconstruction of SVZ network. These characteristics indicate that this subset of trophinin-positive cells in the SVZ is type C cells. Conversely in the RMS, trophinin co-localized with nestin and PSA-NCAM, suggesting that it is expressed in neuroblasts. Cultured neural precursor cells derived from the adult SVZ also expressed both trophinin and bystin. These findings provide insight into the molecular basis of adult neurogenesis in the SVZ and RMS.

Age Factors↗

PubMed2006

[Effect of three-stage sequential method on interleukin-5 mRNA expression in the lung tissue of asthmatic model rat treated with steroid].

OBJECTIVE: To observe the effect of three-stage sequential method (TSSM) on interleukin-5 (IL-5) mRNA expression in the lung tissue of asthmatic rat model treated with steroid. METHODS: SD rats were randomly divided into 8 groups, the normal control group (GA), the model group (GB), the model with steroid intervention group (GC) and the 5 treated groups (GD - GH). Excepting those in the GA, all rats were established into the asthma model and rats in GC-GH were intervened by dexamethasone, with the dosage reduced by 0.1 mg/kg per week starting from the 3rd week and withdrawn completely till the 7th week. At the same time, rats in GD - GH were treated with TSSM, and the 1st, 2nd and 3rd recipe of TSSM, as well as pulmicort respules (as positive control) respectively. IL-5 mRNA expression in the lung tissue of rats was detected at different time points by in situ hybridization. RESULTS: Comparisons of GD with other groups in IL-5 mRNA expression showed: it was remarkably lowered than that in GB and GC at all time points (P < 0.01); compared to GH, the difference was insignificant at the end of the 2nd week, but significant at the end of the 7th and 9th week (P < 0.01); as for the difference between GD with GE, GF and GG, it showed very significant difference (P < 0.01) at all the time points besides that at the end of the 2nd week, it showed insignificance to GE (P > 0.05) and significance to GF (P < 0.05). The dynamic changes of IL-5 mRNA expression in GD during the steroid withdrawal period showed the lowering was more significantly at the end of the 7th and 9th week than that at the end of the 2nd week (P < 0.05, P < 0.01), but its levels were equal at the former two time points; its lowest level appeared at the end of the 9th week, which approaching the level in GA (P > 0.05). CONCLUSION: Three-stage sequential method could remarkably inhibit IL-5 mRNA expression in the lung tissue of asthmatic rats undergoing steroid treatment.

Animals↗

PubMed2005

Activated IGF-1R inhibits hyperglycemia-induced DNA damage and promotes DNA repair by homologous recombination.

The IGF-1R is a genetic determinant of oxidative stress and longevity. Hyperglycemia induces an exponential increase in the production of a key danger signal, reactive oxygen intermediates, which target genomic DNA. Here, we report for the first time that ligand activation of the IGF-1R prevents hyperglycemia-induced genotoxic stress and enhances DNA repair, maintaining genomic integrity and cell viability. We performed single gel electrophoresis (comet assay) to evaluate DNA damage in serum-starved SV40 murine mesangial cells (MMC) and normal human mesangial cells (NHMC), maintained at high ambient glucose concentration. Hyperglycemia inflicted an impressive array of DNA damage in the form of single-strand breaks (SSBs) and double-strand breaks (DSBs). The inclusion of IGF-1 to culture media of MMC and NHMC prevented hyperglycemia-induced DNA damage. To determine whether DNA damage was mediated by reactive oxygen species (ROS), ROS generation was evaluated, in the presence of IGF-1, or the free radical scavenger n-acetyl-cysteine (NAC). IGF-1 and NAC inhibited hyperglycemic-induced ROS production and hyperglycemia-induced DNA damage. We next asked whether IGF-1 promotes the repair of DSB under hyperglycemic conditions, by homologous recombination (HRR) or nonhomologous end joining (NHEJ). Repair of DSB by NHEJ and HRR was operative in MMC maintained under hyperglycemic conditions. IGF-1 increased HRR by nearly twofold, whereas IGF-1 did not affect DNA repair by NHEJ. IGF-1R enhancement of HRR correlated with the translocation of Rad51 to foci of DNA damage. Inhibition of Rad51 expression by short interfering RNA experiments markedly decreased percentage of MMC positive for Rad51 nuclear foci and increased hyperglycemic DNA damage. We conclude that the activated IGF-1R rescues mesangial cells from hyperglycemia-induced danger signals that target genomic DNA by suppressing ROS and enhancing DNA repair by HRR.

Animals↗

PubMed2004

Bystin as a novel marker for reactive astrocytes in the adult rat brain following injury.

Bystin has been identified as a protein which mediates cellular interactions between trophoblastic and endometrial epithelial cells by forming complexes with two partners, trophinin and tastin, during embryo implantation. However, the presence of bystin in the central nervous system has not been demonstrated. Here, we report the cloning of the full-length cDNA of the rat bystin gene from adult brain. Immunohistochemical and RT-PCR analysis showed that the levels of bystin expression were markedly up-regulated in the both 6-hydrodopamine-lesioned rat nigrostriatum and stab-lesioned cerebral cortex in adult rats. Double immunofluorescence staining revealed that most bystin-expressing glial cells were astrocytes (immature or mature). To determine the mechanisms for the up-regulation of bystin expression in glial cells, primary cultures of postnatal cortical astrocytes were employed. Western blot analysis showed that the expression of bystin was elevated by treatment with pro-inflammatory mediators lipopolysaccharide and interleukin-1 beta. Nerve growth factor known to be released after brain injury also induced bystin expression in the cultures. Exposure of astrocyte cultures to the differentiating agent forskolin resulted in up-regulation of bystin followed by a pronounced astrocytic stellation. The results suggest that the injury in the adult brain induces spatiotemporal up-regulation of bystin and it could be influenced, at least in part, by elevation of intracellular cAMP level. Bystin expressed by reactive astrocytes may be involved in their differentiation during the inflammatory processes following brain injury. The reappearance of bystin may also indicate that some reactive astrocytes have the capacity to recapitulate early developmental stages.

Animals↗