Biology subjects

Zhao, Y.

Publications and source records attributed to Zhao, Y..

At least 703 records · Page 39Linked to original sources

bioRxiv2022

Life-course social disparities in body mass index trajectories across adulthood: cohort study evidence from China Health and Nutrition Survey

BackgroundThe social disparities in obesity may originate in early life and adult social class. There are various developmental trajectories of overweight/obesity in adulthood. It is unclear how the intergenerational mobility of socioeconomic status influences adult overweight/obesity in China. MethodsWe used longitudinal data from ten waves of the China Health and Nutrition Survey (CHNS) between 1989 and 2015 for our analysis. The group-based trajectory modeling was used to identify BMI trajectories in adulthood. Multinomial logistic regression was adopted to assess the associations between SES and adult BMI trajectories. ResultsAmong a total of 3,138 participants, three latent clusters, including normal-stable BMI (51.4%), progressive overweight group (39.8%), and progressive obesity group (8.8%), were identified. High fathers occupational position, high participants occupation position and educational attainment, respectively, were associated with greater obesity risk. Compared to a stable low life course SES trajectory, a stable high life course SES trajectory was associated with a 2.35-fold risk of obesity, and upward and downward social mobility trajectories increased the risk for overweight/obesity. Individuals in the highest relative to the lowest life course cumulative socioeconomic score group had around twice risk of obesity. ConclusionsThe results emphasize the role of the high SES in early life and life-course SES accumulation, in the obesity intervention in China. FundingAll the work was supported by the National Natural Science Foundation of China (Grant Nos. 72174167, 81602928) and Natural Science Foundation of Shaanxi (2021JM-031).

scientific communication and education↗

bioRxiv2022

A 4-bp natural deletion of maize Na+/H+ exchanger gene alters maize salt stress tolerance

Soil salinity is a major environmental constraint severely reducing plant growth and crop productivity worldwide. Knowledge of salt tolerance-related genes can facilitate improving crop salt tolerance and alleviating the threat of increasing saline area to world food security. Here, we identified a major locus SALT TOLERANCE 1 (qST1) conferring maize salt tolerance via bulked segregant RNA-Seq (BSR-Seq). qST1 encodes a plasma membrane Na+/H+ exchanger ZmSOS1 which is the ortholog of Arabidopsis thaliana SOS1 gene. In salt-sensitive variety D9H, the natural variation of 4-bp deletion in the coding sequence of ZmSOS1 gene was the causal allele for salt sensitivity. We identified two ethyl methanesulfonate-induced mutants, zmsos1-1 and zmsos1-2, which were sensitive to salt stress and cant complement salt-sensitive variety under salt stress within an allelism test. Overexpression of ZmSOS1 enhanced maize seedling salt tolerance. ZmSOS1 can increase the salt tolerance of Arabidopsis sos1-1 mutant and can be activated by AtSOS2 and AtSOS3 in yeast cells, suggesting that ZmSOS1 confers salt tolerance through the conserved SOS signaling pathway in maize. The detrimental allele harboring the 4-bp deletion was rarely found in the natural population but appeared in an important heterotic group composed of x1132x-derived inbred lines which have been used widely for breeding dozens of hybrid varieties in China. The 4-bp deletion-based molecular marker has been successfully used to improve salt-sensitive varieties in a backcross and marker-assisted breeding program by screening and purging this deleterious allele.

plant biology↗

bioRxiv2022

IL-22/IL-22RA1 promotes human Tenon's capsule fibroblasts proliferation and regulates fibrosis through STAT3 signaling pathway

The study is aimed to investigate that the IL-22/IL-22RA1 signaling pathway regulates scar formation. A total of 31 glaucoma patients who had been previously treated with trabeculectomy surgery and the intraocular pressure was uncontrollable because of scarring and 19 strabismus patients as control patient group. ELISA showed that the IL-22 content of serum from glaucoma patients was 29.80{+/-}5.1 ng/l which is higher than that 5.21{+/-}0.9 ng/l from healthy group significantly. Serum from patients was used to incubate human Tenons capsule fibroblasts (HTFs) cells and IL-22 antibody rescued the effect of IL-22 on the biological functions. qPCR and western blot result showed that IL-22 mediates the biological function of HTFs cells via binding IL-22RA1 directly. When transfection of siR-IL-22RA1 or IL-22RA1 gene, the HTFs cells shown significantly anti-fibrosis or pro-fibrosis separately. By using STAT3 inhibitor BAY in IL-22RA1 overexpression group, IL-22-induced proliferation were reduced in HTFS cells. IL-22 promoted fibroblasts cell proliferation and -SMA via IL-22/IL-22RA1/STAT3 signaling pathway, thereby potentially regulating glaucoma filtration trace fibrosis. This results also show the novel factor in process of postoperative scarring. Summary StatementThe present study suggested that IL-22 expression in glaucoma patient after surgery. IL-22/IL-22RA1 signaling pathway promoted fibroblasts cell proliferation and -SMA by activating the STAT3 signaling pathway, thereby potentially regulating glaucoma filtration trace fibrosis.

cell biology↗

bioRxiv2022

Notch Signaling and Fluid Shear Stress in Regulating Osteogenic Differentiation

Osteoporosis is a common bone and metabolic disease that is characterized by bone density loss and microstructural degeneration. Human bone marrow-derived mesenchymal stem cells (hMSCs) are multipotent progenitor cells with the potential to differentiate into various cell types, including osteoblasts, chondrocytes, and adipocytes, which have been utilized extensively in the field of bone tissue engineering and cell-based therapy. Although fluid shear stress plays an important role in bone osteogenic differentiation, the cellular and molecular mechanisms underlying this effect remain poorly understood. Here, an LNA/DNA nanobiosensor was exploited to monitor mRNA gene expression of hMSCs that were exposed to physiologically relevant fluid shear stress to examine the regulatory role of Notch signaling during osteogenic differentiation. First, the effects of fluid shear stress on cell viability, proliferation, morphology, and osteogenic differentiation were investigated and compared. Our results showed shear stress modulates hMSCs morphology and osteogenic differentiation depending on the applied shear and duration. By incorporating this LNA/DNA nanobiosensor and alkaline phosphatase (ALP) staining, we further investigated the role of Notch signaling in regulating osteogenic differentiation. Pharmacological treatment is applied to disrupt Notch signaling to investigate the mechanisms that govern shear stress induced osteogenic differentiation. Our experimental results provide convincing evidence supporting that physiologically relevant shear stress regulates osteogenic differentiation through Notch signaling. Inhibition of Notch signaling mediates the effects of shear stress on osteogenic differentiation, with reduced ALP enzyme activity and decreased Dll4 mRNA expression. In conclusion, our results will add new information concerning osteogenic differentiation of hMSCs under shear stress and the regulatory role of Notch signaling. Further studies may elucidate the mechanisms underlying the mechanosensitive role of Notch signaling in stem cell differentiation.

bioengineering↗

bioRxiv2022

MHA, an interactive website for scRNA-seq data of male genitourinary development and disease

The development of single-cell sequencing technology has expanded the understanding of cell heterogeneity and disease progression in the male genitourinary system. However, complex processing processes and unprofessional analytical annotations limit the daily use and wildly sharing of published datasets. Here, we describe the Male Health Atlas (MHA), an easy-to-operate online visual website focused on the male genitourinary system, allowing researchers to quickly search for expression patterns of one or multiple genes, and dynamic changes of gene expression during tissue development or under pathological states. At present, the MHA includes nine objects, two species, five types of male genitourinary tissues/organs, and 258,777 single-cell profiles. Compared with other single-cell databases, the MHA has the following advantages: (1) It is easy to operate, and users can complete retrieval and output of results within 5 min without any bioinformatics skills; (2) The selection and analysis of data are under professional supervision of researchers in the male genitourinary field; (3) It contains most of the main male-specific organs and will continue to be updated; (4) MHA provides multi-dimensional output patterns, including tSNE/UMAP, violin, and bubble plot output for displaying single or multiple genes. MHA is the first single-cell database website in the field of andrology and male reproduction, providing researchers with scRNA-seq resources and an accessible tool. MHA is freely available at http://malehealthatlas.cn/.

molecular biology↗

bioRxiv2022

Efficient in vivo neuronal genome editing in the mouse brain using nanocapsules containing CRISPR-Cas9 ribonucleoproteins

Genome editing of somatic cells via clustered regularly interspaced short palindromic repeats (CRISPR) offers promise for new therapeutics to treat a variety of genetic disorders, including neurological diseases. However, the dense and complex parenchyma of the brain and the post-mitotic state of neurons make efficient genome editing challenging. In vivo delivery systems for CRISPR-Cas proteins and single guide RNA (sgRNA) include both viral vectors and non-viral strategies, each presenting different advantages and disadvantages for clinical application. We developed non-viral and biodegradable PEGylated nanocapsules (NCs) that deliver preassembled Cas9-sgRNA ribonucleoproteins (RNPs). Here, we show that the RNP NCs led to robust genome editing in neurons following intracerebral injection into the mouse striatum. Genome editing was predominantly observed in medium spiny neurons (>80%), with occasional editing in cholinergic, calretinin, and parvalbumin interneurons. Glial activation was minimal and was localized along the needle tract. Our results demonstrate that the RNP NCs are capable of safe and efficient neuronal genome editing in vivo. SIGNIFICANCE STATEMENTModifying the DNA of cells in the brain could present opportunities for new treatments of neurological diseases. In this report, we describe a nanocapsule system designed to deliver the elements needed to modify the DNA of brain cells, also known as genome editing. These nanocapsules are created by chemically encapsulating the genome editing components, such that the nanocapsules are stable when prepared and biodegradable to release their payload upon entering cells. When injected into the mouse brain, our research shows that the nanocapsules lead to safe and efficient editing of DNA in neurons.

neuroscience↗

bioRxiv2022

Bioinformatics analysis of immune-related prognostic genes and immunotherapy in renal clear cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is an immunogenic tumor and investigating the immunorelated genes is of great significance. To investigate the immunoprognostic genes of ccRCC, we analyzed the data assimilated from a public database (The Cancer Genome Atlas (TCGA) database and the gene expression omnibus (GEO) database) using bioinformatics. Then, a immunoprognosis model was constructed to identify 4 hub genes with moderate predictive values for the prognosis of ccRCC patients. Interestingly, these 4 genes were associated with the prognosis of ccRCC patients based on Oncomine and Gena Expression Profiling Interactive Analysis (GEPIA) databases. The correlation analysis between the immune infiltrate, immune checkpoints, and immunotherapy and this immunoprognosis model showed that immune infiltrate and could predict the immunotherapy effects. We also conducted a quantitative real-time polymerase chain reaction analysis and found that the expressions of 3 hub genes were associated with tumor progression (P<0.1). In conclusion, 4 genes that may serve as potential biomarkers in ccRCC were identified with respect to prognosis.

cancer biology↗

bioRxiv2022

Analysis of the mechanism of castor tolerance to Cd metal based on proteomics and metabolomics

The pollution of soil with heavy metals is an increasingly serious worldwide problem, and cadmium (Cd) has attracted attention because of its high toxicity to almost all plants. Since castor tolerates the accumulation of heavy metals, it has the potential for heavy metal soil remediation. We studied the mechanism of the tolerance of castor to Cd stress treatments at three doses: 300 mg/L, 700 mg/L, and 1,000 mg/L. Our research provides new ideas for revealing the defense and detoxification mechanisms of Cd-stressed castor. By combining the results of physiology, differential proteomics and comparative metabolomics, we conducted a comprehensive analysis of the networks that regulate the response of castor to Cd stress. The physiological results mainly emphasize the super-sensitive responses of castor plant roots to Cd stress and the effects of Cd stress on plants antioxidant system, ATP synthesis and ion homeostasis. We confirmed these results at the protein and metabolite levels. At the same time, proteomics and metabolomics show that castor plants mainly block the root systems absorption of Cd2+ by enhancing the strength of the cell wall, and inducing programmed cell death in response to the three different doses of Cd stress. In addition, the plasma membrane ATPase encoding gene (RcHA4), which was significantly upregulated in our differential proteomics and RT-qPCR studies, was transgenically overexpressed in wild type Arabidopsis thaliana for functional verification. The results indicated that this gene plays an important role in improving plant Cd tolerance.

molecular biology↗

bioRxiv2022

Adrenal sympathetic nerve mediated the anti-inflammatory effect of electroacupuncture at ST25 acupoint on a rat model of sepsis

Acupuncture plays a vital anti-inflammatory action on sepsis through activating autonomic nerve anti-inflammatory pathways, such as sympathoadrenal medullary pathway, but the mechanism remains unclear. This study aims to explore the optimum parameter of electroacupuncture (EA) stimulation in regulating sympathoadrenal medullary pathway and evaluate EAs anti-inflammatory effect on sepsis. To explore the optimum parameter of EA at homosegmental acupoint on adrenal sympathetic activity, the left adrenal sympathetic nerve firing rate evoked by different intensities of single shock electrical stimulation (ES) at ST25 in healthy male Sprague-Dawley (SD) rats were evaluated by in vivo electrophysiological recording, and the levels of norepinephrine (NE) and its metabolites were also examined using mass spectrometry. To verify the role of EA at ST25 in sepsis, the rat was given intraperitoneal injection lipopolysaccharide to induce sepsis model, and survival rate, clinical score, and the level of interleukin (IL)-6, IL-1{beta}, and IL-10 were evaluated after EA application. We observed that 3 mA is the optimal intensity on activating adrenal sympathetic nerve, which significantly elevated the level of NE in the peripheral blood. For LPS-treated rats, EA at the ST25 apparently increased the survival rate and improved the clinical score compared to the control group. Furthermore, 3 mA EA at ST25 significantly decreased pro-inflammatory cytokines IL-6 and IL-1{beta} and upregulated anti-inflammatory cytokine IL-10 compared to the Lipopolysaccharide (LPS)-treated group. Overall, these data suggest that 3 mA is the optimal EA intensity at ST25 to activate the sympathoadrenal medullary pathway and exert an anti-inflammatory effect on sepsis. HighlightsO_LI3 mA single shock ES at ST25 drove adrenal sympathetic nerve reflexs. C_LIO_LI3 mA EA at ST25 upregulated NE concentration in peripheral blood. C_LIO_LIEA at ST25 improved the survival rate in a rat of LPS-induced sepsis model. C_LIO_LIEA at the ST25 upregulated anti-inflammatory IL10 and downregulated pro-inflammatory IL1{beta} and IL-6 in LPS-treated rats. C_LI

neuroscience↗

bioRxiv2022

Synthetic yeast chromosome XI design enables extrachromosomal circular DNA formation on demand

We describe construction of the 660 kilobase synthetic yeast chromosome XI (synXI) and reveal how synthetic redesign of non-coding DNA elements impact the cell. To aid construction from synthesized 5 to 10 kilobase DNA fragments, we implemented CRISPR-based methods for synthetic crossovers in vivo and used these methods in an extensive process of bug discovery, redesign and chromosome repair, including for the precise removal of 200 kilobases of unexpected repeated sequence. In synXI, the underlying causes of several fitness defects were identified as modifications to non-coding DNA, including defects related to centromere function and mitochondrial activity that were subsequently corrected. As part of synthetic yeast chromosome design, loxPsym sequences for Cre-mediated recombination are inserted between most genes. Using the GAP1 locus from chromosome XI, we show here that targeted insertion of these sites can be used to create extrachromosomal circular DNA on demand, allowing direct study of the effects and propagation of these important molecules. Construction and characterization of synXI has uncovered effects of non-coding and extrachromosomal circular DNA, contributing to better understanding of these elements and informing future synthetic genome design.

synthetic biology↗

bioRxiv2022

Integrated single-cell sequencing analysis reveals peripheral immune landscape across the human lifespan

Systematic understanding of immune dynamics across the entire human lifespan at single-cell resolution is currently lacking. Here, we performed single-cell RNA sequencing (scRNA-seq) and single-cell T cell receptor (TCR)/B cell receptor (BCR) sequencing (scTCR/BCR-seq) on over 380,000 peripheral blood mononuclear cells collected from 45 healthy participants aged 0 to over 90 years. We revealed that the functions of T cell subsets were most susceptible to senescence among all PBMCs, featured by increased NF-{kappa}B signaling and IFN-{gamma} responses pathways, while reduced telomere maintenance and energy metabolism. We subsequently explored the rewiring of cell-cell interactions among different immune cells across the lifespan and revealed the major alteration of immune checkpoints in T cells within the cellular interaction networks. By combined analysis of scRNA-seq and scTCR-seq, we revealed that 1) GNLY+ CD8 Effector T cells exhibited a high clonal expansion with distinct functional signatures in children and the elderly; 2) Naive CD4+ T and naive CD8+ T cells displayed different aging patterns in both transcriptomes and immune repertoires; and 3) CD8+ MAIT cells showed a higher cell abundance and clonal diversity in adolescents. Furthermore, we identified a unique cytotoxic B cell subset enriched in children by scRNA-seq and scBCR-seq analysis and experimental validations. In summary, our work provided valuable insights and rich resources for understanding the development and aging of the human immune system across the lifespan.

immunology↗

bioRxiv2022

Quinolinate promotes alternatively activated macrophage-induced immune tolerance in glioblastoma through the NMDA/PPARγ signaling axis

There has been considerable scientific effort dedicated to understanding the biologic consequence and therapeutic implications of aberrant tryptophan metabolism in brain tumors and neurodegenerative diseases. An overwhelming majority of this work has focused on the upstream metabolism of tryptophan; however, this has not resulted in clinical application. Using global metabolomic profiling of patient-derived brain tumors, we identify the downstream metabolism of tryptophan and accumulation of quinolinate (QA) as a metabolic node in glioblastoma and went on to demonstrate its critical role in promoting immune tolerance. QA acts as a "metabolic checkpoint" in glioblastoma by inducing NMDA receptor activation and Foxo1/PPAR{gamma} signaling, resulting in amplification of immune suppressive macrophages. Using a genetically-engineered mouse model designed to inhibit production of QA, we identify kynureninase as a promising therapeutic target to revert the potent immune suppressive microenvironment in glioblastoma. These findings offer the scientific community an opportunity to revisit the biologic consequence of this pathway as it relates to oncogenesis and neurodegenerative disease and a framework for developing new immune modulatory agents to further clinical gains in these otherwise incurable diseases.

cancer biology↗

bioRxiv2022

Growth mindset promotes children's working memory performance through cortico-striatal interaction and fronto-parietal activation

Growth mindset--the belief that abilities are malleable through effort--drives motivation, action and achievement. Yet, the underlying mechanisms remain elusive, necessitating a unified framework that integrates cognitive, neural, and developmental processes. Leveraging longitudinal neuroimaging and computational modeling to reveal moment-to-moment decision responses and brain state dynamics during working memory (WM), we show that growth mindset enhances WM development from middle childhood to adolescence via nuanced cortico-striatal network dynamics that balance between brain state flexibility and stability. Behaviorally, children with higher growth mindset exhibited better WM performance both cross-sectionally and longitudinally, attributed to faster evidence accumulation during moment-to-moment information updating, especially under high task demands. Neurally, a higher growth mindset was associated with greater activation of the dorsal striatum, cingulo-opercular (action-mode), and fronto-parietal networks during WM, which further accounted for longitudinal WM improvement and latent evidence accumulation. Such cortico-striatal activation covaried with neurochemical mediators critical for motivation and executive functioning. Analyzing non-stationary network dynamics revealed that growth mindset optimized dynamical organization of cortico-striatal networks, with an activated state highly flexible to support moment-to-moment information updating and a deactivated state remaining stable across blocks to suppress irrelevant information. This suggests a balanced allocation of resources for accumulating evidence while suppressing noise during WM. Together, our findings support a neurocognitive framework in which growth mindset enhances WM development via nuanced orchestration of cortico-striatal networks to enable efficient dynamic computations and foster far-reaching cognitive development.

neuroscience↗

bioRxiv2022

White matter connectivity in uncinate fasciculus accounts for visual attention span in developmental dyslexia

The present study aimed to investigate the role of connectivity disruptions in two fiber pathways, the uncinate fasciculus (UF) and the frontal aslant tract (FAT), in developmental dyslexia and determine the relationship between the connectivity of these pathways and behavioral performance in children with dyslexia. A total of 26 French children with dyslexia and 31 age-matched control children were included. Spherical deconvolution tractography was used to reconstruct the two fiber pathways. Hindrance-modulated oriented anisotropy (HMOA) was used to measure the connectivity of each fiber pathway in both hemispheres. The boys with dyslexia showed reduced HMOA in the UF compared to control boys, but this difference was not observed in girls. Furthermore, HMOA of the UF correlated with individual differences in the visual attention span in participants with dyslexia. All significant results found in HMOA of the UF were verified in fractional anisotropy (FA) of the UF using standard diffusion imaging model. This study suggests a differential sex effect on the connectivity disruption in the UF in developmental dyslexia. It also indicates that the UF may play an essential role in the visual attention span deficit in developmental dyslexia. Significance StatementThis study presents the first account of connectivity disruption in the uncinate fasciculus in developmental dyslexia. In particular, this connectivity disruption only appears in boys with dyslexia but not in girls with dyslexia. We also show that the connectivity of the uncinate fasciculus accounts for individual differences in the visual attention span in children with dyslexia, expanding the current understanding of the function of the uncinate fasciculus.

neuroscience↗

bioRxiv2022

FOXP2 confers oncogenic effects in prostate cancer through activating MET signalling

Identification oncogenes is fundamental to revealing the molecular basis of cancer. Here, we found that FOXP2 is overexpressed in human prostate cancer cells and prostate tumors, but its expression is absent in normal prostate epithelial cells and low in benign prostatic hyperplasia. To date, little is known regarding the link of FOXP2 to prostate cancer. We observed that high FOXP2 expression and frequent amplification are significantly associated with high Gleason score. Ectopic expression of FOXP2 induces malignant transformation of mouse NIH3T3 fibroblasts and human prostate epithelial cell RWPE-1. Conversely, FOXP2 knockdown suppresses the proliferation of prostate cancer cells. Transgenic overexpression of FOXP2 in the mouse prostate causes prostatic intraepithelial neoplasia. Overexpression of FOXP2 aberrantly activates oncogenic MET signalling and inhibitors targeting MET signalling effectively reverts the FOXP2-induced oncogenic phenotype. Additionally, the novel recurrent FOXP2-CPED1 fusion identified in prostate tumors results in high expression of truncated FOXP2, which exhibit a similar capacity for malignant transformation. Together, our data demonstrate for the first time that FOXP2 is an oncogene involved in tumorigenicity of prostate.

cancer biology↗

bioRxiv2022

Integrating analog and digital modes of gene expression at Arabidopsis FLC

Quantitative gene regulation at the cell population-level can be achieved by two fundamentally different modes of regulation at individual gene copies. A "digital" mode involves binary ON/OFF expression states, with population-level variation arising from the proportion of gene copies in each state, while an "analog" mode involves graded expression levels at each gene copy. At the Arabidopsis floral repressor FLOWERING LOCUS C (FLC), "digital" Polycomb silencing is known to facilitate quantitative epigenetic memory in response to cold. However, whether FLC regulation before cold involves analog or digital modes is unknown. Using quantitative fluorescent imaging of FLC mRNA and protein, together with mathematical modelling, we find that FLC expression before cold is regulated by both analog and digital modes. We observe a temporal separation between the two modes, with analog preceding digital. The analog mode can maintain intermediate expression levels at individual FLC gene copies, before subsequent digital silencing, consistent with the copies switching OFF stochastically and heritably without cold. This switch leads to a slow reduction in FLC expression at the cell population-level. These data present a new paradigm for gradual repression, elucidating how analog transcriptional and digital epigenetic memory pathways can be integrated.

molecular biology↗

bioRxiv2022

Metformin protects trabecular meshwork against oxidative injury via activating integrin/ROCK signals

BackgroundThis study aimed to investigate the protective effect of metformin on the trabecular meshwork (TM) and explore its molecular mechanisms in vivo and in vitro. MethodsOcular hypertension (OHT) mouse models were induced with dexamethasone (DEX) and further treated with metformin to determine its IOP lowering effect. Cultured human TM cells (HTMC) were pre-stimulated with tert-butyl hydroperoxide (tBHP) to induce oxidative damage and then supplemented with metformin for another 24 h. The expression of fibrotic markers and integrin/ROCK signals, including -SMA, TGF-{beta}, fibronectin, F-actin, integrin beta 1, Rho-associated kinase (ROCK)1/2, AMP-activated protein kinase (AMPK), myosin light chain 1 (MLC 1), and F-actin were determined by western blotting (WB) and immunofluorescence (IF). Reactive oxygen species (ROS) content was analysed using flow cytometry (FCM). ResultsAdministration of metformin reduced the elevated IOP and alleviated the fibrotic activity of aqueous humour outflow in OHT models. Additionally, metformin rearranged the disordered cytoskeleton in the TM both in vivo and in vitro. Furthermore, metformin significantly inhibited ROS production and activated integrin/ROCK signalling induced by tBHP in HTMC. ConclusionMetformin reduced the elevated IOP in steroid-induced OHT mouse models and exerted its protective effects against oxidative injury by regulating cytoskeleton remodelling through the integrin/ROCK pathway. This study provides new insights into metformin use and preclinical evidence for the potential treatment of primary open-angle glaucoma.

pharmacology and toxicology↗

bioRxiv2022

Small cytosolic dsDNAs repress cGAS activation and induce autophagy

Cyclic GMP-AMP (cGAMP) synthase (cGAS), a major cytosolic DNA sensor, activates innate immune responses by producing cGAMP, which activates stimulator of interferon genes (STING)1. Cytosolic DNA induces autophagy in a cGAS-dependent manner to avoid persistent immune stimulation. Although dsDNAs < 20 bp can bind to cGAS, robust cGAS activation requires dsDNAs > 45 bp 2-4. However, whether cytosolic dsDNAs < 45 bp exist in mammalian cells remains unclear. Here, we identified a class of small cytosolic DNAs (scDNAs) of [~]20-40 bp in human and mouse cell lines. scDNAs competed with herring testis DNA (HT-DNA, [~]200-1500 bp) for binding to cGAS, and repressing HT-DNA-induced cGAS activation and the associated interferon {beta} (IFN{beta}) production. Moreover, scDNAs promoted cGAS and Beclin-1 interaction, triggering the release of Rubicon, a negative regulator of phosphatidylinositol 3-kinase class III (PI3KC3)5,6, from the Beclin-1-PI3KC3 complex, activating PI3KC3 and inducing autophagy. DNA damage decreased and autophagy inducers increased scDNA levels. scDNA transfection or autophagy induction attenuated DNA damage-induced cGAS-STING activation and IFN{beta} expression. Thus, scDNAs acted as molecular brakes of cGAS activation, preventing excessive inflammatory cytokine production following DNA damage. Our findings lay foundations for understanding the physiological and pathological functions of scDNAs.

molecular biology↗