Biology subjects

Meng, Y.

Publications and source records attributed to Meng, Y..

At least 73 records · Page 4Linked to original sources

bioRxiv2022

A bioinformatics approach to systematically analyze the molecular patterns of monkeypox virus-host cell interactions

Monkeypox has been spreading worldwide since May 2022, when the World Health Organization (WHO) declared the outbreak of a "Public health emergency of international concern". The spread of monkeypox has posed a serious threat to the health of people all over the world but few studies have been carried out on it, and the molecular mechanism of monkeypox after infection remains unclear. We therefore implemented a transcriptome analysis to identify signaling pathways and biomarkers in monkeypox-infected cells to help understand monkeypox-host cell interactions. In this study, the dataset GSE36854 and GSE11234 were obtained from GEO. Among them, 84 significantly different genes were identified in the dataset GSE36854, followed by KEGG, GO analysis protein-protein interaction (PPI) construction and Hub gene extraction. We also analyzed the expression regulation patterns of hub genes and screened the drugs targeting the hub genes. The results showed that monkeypox-infected cells significantly activated the cellular immune response, and induced inflammatory response. IER3, IFIT2, IL11, ZC3H12A, EREG, IER2, NFKBIE, FST, IFIT1 and AREG were the top 10 hub genes, in which anti-viral gene IFIT1 and IFIT2 were significantly suppressed. AP-26113 and itraconazole promoting the expression of IFIT1 and IFIT2 may be used as new candidates for the treatment of monkeypox viral infection. Our results provide a new entry point for understanding the mode of interaction between monkeypox virus and its host.

microbiology↗

bioRxiv2022

The role and mechanism of NRF2 in endothelial cells and smooth muscle cells of pulmonary artery

Pulmonary hypertension (PH) is a kind of fatal disease. There are no existing drugs that could reverse the diseas. NF-E2-related factor 2 (NRF2) is one of the most important moleculars in the range of cell protection. We examined the expression of NRF2 in PH models and explored the role of NRF2 in regulating abnormal phenotypes in pulmonary artery cells. We determined the expression level of NRF2 in lung tissues of PH model decreased significantly. We found that NRF2 was reduced in rat pulmonary artery endothelial cells (rPAEC) under hypoxia, while it was overexpressed in rat pulmonary artery smooth muscle cells (rPASMC) under hypoxia. Next, the results showed that knockdown NRF2 in rPAEC promoted endothelial-mesenchymal transformation and upregulated reactive oxygen species level. After the rPASMC was treated with siRNA or activator, we found that NRF2 could promote cell proliferation by regulating PDGFR/ERK1/2 and mTOR/P70S6K pathways, and accelerate cell migration by affecting MMP2/3/7. Therefore, the study suggests that the combination of NRF2 activators should be considered to eliminate the promoting effect of NRF2 activators on proliferation and migration of rPASMC. Summary statementHypoxia regulates NRF2 in PAECs and PASMCs differently. We found that NRF2 could promote cell proliferation by regulating PDGFR/ERK1/2 and mTOR/P70S6K pathways, and accelerate cell migration by affecting MMP2/3/7.

cell biology↗

bioRxiv2022

A mutant bacterial O-GlcNAcase visualizes a progressive decline of protein O-GlcNAcylation in early Drosophila embryos critical for neurodevelopment

Protein O-GlcNAcylation, a monosaccharide posttranslational modification maintained by two evolutionarily conserved enzymes, O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA), is a major nutrient sensor integrating key metabolic pathways. While mutations in OGT have recently been associated with neurodevelopmental disorders, the dynamics and function of protein O-GlcNAcylation during early embryogenesis remain elusive. Here we develop a new fluorescent probe to visualize O-GlcNAcylation levels in live Drosophila early embryos. Our study shows that protein O-GlcNAcylation declines as the embryos develop to the mid-blastula transition when the facultative heterochromatin makes its first appearance. Lowering O-GlcNAcylation levels by exogenous OGA activity promotes the polycomb group O-GlcNAc protein Polyhomeotic (Ph) to form nuclear foci and K27 trimethylation of histone H3. This enhanced facultative heterochromatin formation fine-tunes the expression of several neurodevelopmental genes including short of gastrulation (sog). We provide evidence that perturbation of O-GlcNAcylation during early embryogenesis affects learning ability in adulthood, highlighting the importance of O-GlcNAcylation homeostasis for the development of the nervous system.

developmental biology↗

bioRxiv2022

PRC2 Inactivating Mutations in Cancer are Synthetic Lethal with DNMT1 Targeted Therapy via Enhanced Viral Mimicry

Polycomb Repressive Complex 2 (PRC2) establishes and maintains di- and tri-methylation at histone 3 at lysine 27 (H3K27me2/3) in the genome and plays oncogenic and tumor suppressor roles in context-dependent cancer pathogenesis. While there is clinical success of therapeutically targeting PRC2 core component, EZH2, in PRC2-dependent cancers (e.g., follicular lymphoma, epithelioid sarcoma), it remains an unmet therapeutic bottleneck in PRC2-inactivated cancer. Biallelic inactivating mutations in PRC2 core components are a hallmark feature of high-grade malignant peripheral nerve sheath tumor (MPNST), an aggressive subtype of sarcoma with poor prognosis and no effective targeted therapeutics. Using a custom RNAi-based drop out screen, we observed that PRC2-inactivation is synthetic lethal with DNA methyltransferase 1 (DNMT1) downregulation; we further observed that small molecule DNMT inhibitors (DNMTis) resulted in enhanced cytotoxicity and antitumor response in PRC2-loss cancer context in vitro and in vivo. Mechanistically, DNMTi-mediated de-repression of retrotransposons (e.g., endogenous retroviral elements (ERVs)/LTR, LINE, SINE) and gene targets is partly restricted by PRC2, which potentially contributes to limited therapeutic activity in PRC2-wild-type (wt) cancer context. In contrast, DNMTi treatment synergizes with PRC2 inactivation and cooperatively amplifies the expression of retrotransposons (e.g., ERV/LTR, LINE, SINE), and subsequent viral mimicry response that promotes robust cell death in part through PKR-dependent double stranded-RNA (dsRNA) sensing. Collectively, our observations posit DNA methylation as a safeguard against anti-tumorigenic cell fate decisions in the context of PRC2-inactivation to promote cancer pathogenesis. Further, they identified a novel targeted therapeutic strategy in PRC2-inactivated MPNST and delineated the PRC2-inactivated cancer context for future preclinical exploration and clinical investigation of DNMT1-targeted therapies in cancer. SIGNIFICANCEPRC2-inactivation drives oncogenesis in various cancers but therapeutically targeting PRC2-loss has remained challenging. Here we show that PRC2 inactivating mutations sets up a tumor context-specific liability for synthetic lethal interaction with genetic and therapeutic inhibition of DNMT1. DNMT1 inhibitor-induced cytotoxicity in PRC2-loss cancer context is accompanied by innate immune signaling signature through PKR-mediated sensing of endogenous retrotransposons. These observations posit a therapeutic window via direct anti-tumor effect by DNMT1 inhibitors in PRC2-loss cancers, and point to potentials to be combined with innovative immunotherapeutic strategies to capitalize on innate immune signaling activation.

cancer biology↗

bioRxiv2022

Macroscale Thalamic Functional Organization Disturbances And Underlying Core Cytoarchitecture In Early-Onset Schizophrenia

Schizophrenia is a polygenetic mental disorder with heterogeneous positive and negative symptom constellations, and is associated with abnormal cortical connectivity. The thalamus has a coordinative role in cortical function and is key to the development of the cerebral cortex. Conversely, altered functional organization of the thalamus might relate to overarching cortical disruptions in schizophrenia, anchored in development. Here, we contrasted resting-state fMRI in 99 antipsychotic-naive first-episode early-onset schizophrenia (EOS) patients and 100 typically developing controls to study whether macroscale thalamic organization is altered in EOS. Employing dimensional reduction techniques on thalamocortical functional connectome, we derived lateral-medial and anterior-posterior thalamic functional axes. We observed increased segregation of macroscale thalamic functional organization in EOS patients, which was related to altered thalamocortical interactions both in unimodal and transmodal networks. Using an ex vivo approximation of core-matrix cell distribution, we found that core cells particularly underlie the macroscale abnormalities in EOS patients. Moreover, the disruptions were associated with schizophrenia-related gene expression maps. Behavioral and disorder decoding analyses indicated that the macroscale hierarchy disturbances might perturb both perceptual and abstract cognitive functions and contribute to negative syndromes in schizophrenia, suggesting a unitary pathophysiological framework of schizophrenia.

neuroscience↗

bioRxiv2022

TIR-catalyzed ADP-ribosylation reactions produce signaling molecules for plant immunity

Plant pathogen-activated immune signaling by nucleotide-binding leucine-rich repeat (NLR) receptors with an N-terminal Toll/Interleukin-1 receptor (TIR) domain converges on Enhanced Disease Susceptibility 1 (EDS1) and its direct partners Phytoalexin Deficient 4 (PAD4) or Senescence-Associated Gene 101 (SAG101). TIR-encoded NADases produce signaling molecules to promote exclusive EDS1-PAD4 and EDS1-SAG101 interactions with helper NLR sub-classes. Here we show that TIR-containing proteins catalyze adenosine diphosphate (ADP)-ribosylation of adenosine triphosphate (ATP) and ADP ribose (ADPR) via ADPR polymerase-like and NADase activity, forming ADP-ribosylated ATP (ADPr-ATP) and ADPr-ADPR (di-ADPR), respectively. Specific binding of di-ADPR or ADPr-ATP allosterically promotes EDS1-SAG101 interaction with helper NLR N requirement gene 1A (NRG1A) in vitro and in planta. Our data reveal an enzymatic activity of TIRs that enables specific activation of the EDS1-SAG101-NRG1 immunity branch.

plant biology↗

bioRxiv2022

Identification and receptor mechanism of TIR-catalyzed small molecules in plant immunity

Plant nucleotide-binding leucine-rich-repeat receptors (NLRs) with an N-terminal toll/interleukin-1 receptor (TIR) domain sense pathogen effectors to enable TIR-encoded NADase activity for immune signaling. TIR-NLR (TNL) signaling requires conserved helper NLRs NRG1 and ADR1 and the lipase-like protein EDS1 that functions as a heterodimer with each of its paralogs PAD4 and SAG101. We show that TIR-containing proteins catalyze production of 2-(5-phosphoribosyl)-5-adenosine mono-/di-phosphate (pRib-AMP/ADP) in vitro and in planta. Biochemical and structural data demonstrate that EDS1-PAD4 is a receptor complex for pRib-AMP/ADP. pRib-ADP binding triggers a conformational change in the PAD4 C-terminal domain to allosterically promote EDS1-PAD4 interaction with ADR1-L1 but not NRG1A. Our study identifies TIR-catalyzed pRib-AMP/ADP as a missing link in TIR signaling via EDS1-PAD4 and as likely second messengers for plant immunity.

plant biology↗

bioRxiv2022

Predicting plant-related and leaf-related parameters of winter wheat using vegetation index: Should phenological correction be applied across growth stages?

Most existing plant-related and leaf-related parameters models of winter wheat vary across growing seasons, but it is an open question whether a unified statistical model can be developed to predict plant-related and leaf-related parameters using VI across multiple growing seasons, or whether the phenological correction is necessary for each parameter across multiple growing seasons. To explore this question, we measured two plant-related parameters and four leaf-related parameters over five growth stages during the 2017-2021 growing seasons. A hierarchical linear model (HLM) automatically adapts the relationship between VIs and their corresponding parameter across growing seasons and assesses the contribution of phenological variables by applying a sensitivity analysis. The estimates of VI-plant-related parameters [aboveground dry biomass (AGB) and plant nitrogen concentration (PNC)] were scattered over a given growing season, unlike the relationship between VI-leaf-related parameters [leaf dry biomass (LGB), leaf nitrogen concentration (LNC), leaf area index (LAI) and soil and plant analysis development (SPAD)]. In contrast, the AGB, PNC, LGB, LNC, LAI, and SPAD HLM models are stable and can be popularized across growing seasons, with the determination coefficient R2 ranging from 0.84 to 0.86, 0.79 to 0.87, 0.70 to 0.71, 0.68 to 0.86, 0.75 to 0.81, and 0.68 to 0.70, respectively, and the root mean square error ranging from 0.13 to 0.50 t/ha, 0.01 to 0.07%, 0.01 to 0.03 t/ha, 0.02 to 0.03%, 0.02 to 0.07, and 0.47 to 0.69, respectively. The sensitivity index of the phenological information in the AGB and PNC models was 0.56-0.78 and 0.66-0.72, respectively, whereas that in the LGB, LNC, LAI, and SPAD models was 0.01-0.06, 0.01-0.10, 0.02-0.06, and 0.00-0.01, respectively. Although phenological effects have little effect on leaf-related indicators, HLM has a strong potential for application to other crops and regions.

ecology↗

bioRxiv2022

Mechanism of Voltage Gating in the Voltage-Sensing Phosphatase Ci-VSP

The conformational changes in voltage-sensing domain (VSD) are driven by the transmembrane electric field acting on charges and countercharges. Yet, the overall energetics and detailed mechanism of this process are not fully understood. Here, we determined free energy and displacement charge landscapes, as well as major conformations corresponding to a complete functional gating cycle in the isolated voltage-sensing domain of the phosphatase Ci-VSP (Ci-VSD) comprising four transmembrane helices (segments S1-S4). Molecular dynamics simulations highlight the extent of S4 movements. In addition to the crystallographically determined activated Up and resting Down states, the simulations predict two novel Ci-VSD conformations: a deeper resting state ( Down-minus) and an extended activated ( Up-plus) state. These additional conformations were experimentally probed via systematic cysteine mutagenesis with metal-ion bridges and the engineering of proton conducting mutants at hyperpolarizing voltages. These results show that voltage activation involves sequentially populating these four states in a stepwise way, translating one arginine across the membrane electric field per step, transferring ~3 e0 charges.

biophysics↗

bioRxiv2022

Comparative miRNA Transcriptomics of Mouse and Macaque Reveals Cytoskeleton is An Inhibitor for C. neoformans Invasion into Brain

Cryptococcal meningoencephalitis is an emerging infection shifted from primarily ART-naive to being ART-experienced HIV/AIDS patients, COVID-19 patients and also in immune competent individuals, mainly caused by the human opportunistic pathogen Cryptococcus neoformans, yet mechanisms of the brain or CNS dissemination remain to elucidate, which is the deadest process for the disease. Meanwhile, illustrations of clinically relevant responses in cryptococcosis were limited, as the low availabilities of clinical samples. In this study, macaque and mouse infection models were employed and miRNA-mRNA transcriptomes were performed and combined, which revealed cytoskeleton, a major feather in HIV/AIDS patients, was a centric pathway regulated in both two infection models. Notably, assays of clinical immune cells confirmed an enhanced "Trojan Horse" in HIV/AIDS patients, which can be shut down by cytoskeleton inhibitors. Furthermore, we identified a novel enhancer for macrophage "Trojan Horse", myocilin, and an enhanced fungal burden was achieved in brains of MYOC transgenic mice. Taking together, this study reveals fundamental roles of cytoskeleton and MYOC in blocking fungal CNS dissemination, which not only helps to understand the high prevalence of cryptococcal meningitis in HIV/AIDS, but also facilitates the development of novel drugs for therapies of meningoencephalitis caused by C. neoformans and other pathogenic microorganisms.

microbiology↗

bioRxiv2022

The new archaeal order Lutiacidiplasmatales reveals convergent evolution in Thermoplasmatota

The archaeal Terrestrial Miscellaneous Euryarchaeota Group (TMEG) has been identified in various environments, and the single genome investigated thus far suggests that these organisms are anaerobic sulfite reducers. We assembled 35 new TMEG genomes that, based on genome analysis, appear to possess aerobic and facultative anaerobic lifestyles and may oxidise rather than reduce sulfite. We propose naming this order (representing 16 genera) "Lutiacidiplasmatales" due to their occurrence in various acidic environments and placement within the phylum Thermoplasmatota. A phylum-level analysis revealed that Thermoplasmatota evolution had been punctuated by several periods of high levels of novel gene family acquisition. Several essential metabolisms, such as aerobic respiration and acid tolerance, were likely acquired independently by divergent lineages through convergent evolution rather than inherited from a common ancestor. Ultimately, this study describes the terrestrially prevalent Lutiacidiciplasmatales and indicates convergent evolution as an important evolutionary driving force in archaeal lineages with complex histories.

microbiology↗

bioRxiv2022

A Genome-wide CRISPR Screen Identifies WDFY3 as a Novel Regulator of Macrophage Efferocytosis

AbstractsPhagocytic clearance of dying cells, termed efferocytosis, must occur efficiently to maintain homeostasis and prevent disease. Yet, our understanding of this important biological process remains incomplete. To search for novel regulators of efferocytosis, we performed a FACS-based genome-wide CRISPR knockout screen in primary murine macrophages. We identified a novel role for WDFY3 in efferocytosis by macrophages. WDFY3 deficiency in macrophages specifically impaired uptake, not binding, of apoptotic cells due to defective actin depolymerization. We further revealed that WDFY3 directly interacts with GABARAP, thus facilitating LC3 lipidation and subsequent lysosomal acidification to permit the degradation of apoptotic cell components. Although the C-terminus of WDFY3 was sufficient to rescue impaired degradation, full-length WDFY3 is still required for regulating uptake. Finally, WDFY3 is required for efficient efferocytosis in vivo in mice and in primary human macrophages. The work expands our knowledge of the mechanisms of macrophage efferocytosis, and more broadly, provides a general strategy for genome-wide CRISPR screen to interrogate complex functional phenotypes in primary macrophages. HighlightsO_LIFunctional readout for pooled genome-wide CRISPR screen in primary macrophages. C_LIO_LIWDFY3 is discovered as a regulator of macrophage efferocytosis in vitro and in vivo. C_LIO_LIWDFY3 deficiency led to impaired uptake, as opposed to binding, of apoptotic cells due to defective actin depolymerization. C_LIO_LIWDFY3 directly interacts with GABARAP, facilitating LC3 lipidation and subsequent lysosomal acidification to permit the degradation of apoptotic cell components. C_LIO_LIC-terminal WDFY3 is sufficient to regulate the degradation of engulfed apoptotic cells while full-length WDFY is required for regulating uptake. C_LI

cell biology↗

bioRxiv2022

Identification and Age-dependent Increase of Platelet Biased Human Hematopoietic Stem Cells

Hematopoietic stem cells (HSC) reconstitute multi-lineage human hematopoiesis after clinical bone marrow transplantation and are the cells-of-origin of hematological malignancies. Though HSC provide multi-lineage engraftment, individual murine HSCs are lineage-biased and contribute unequally to blood cell lineages. Now, by combining xenografting of molecularly barcoded adult human bone marrow (BM) HSCs and high-throughput single cell RNA sequencing we demonstrate that human individual BM HSCs are also functionally and transcriptionally lineage biased. Specifically, we identify platelet-biased and multi-lineage human HSCs. Quantitative comparison of transcriptomes from single HSCs from young, and aged, BM show that both the proportion of platelet-biased HSCs, and their level of transcriptional platelet priming, increases with age. Therefore, platelet-biased HSCs, as well as their increased prevalence and elevated transcriptional platelet priming during ageing, are conserved between human and murine hematopoiesis. One-Sentence SummaryIn vivo barcoding and single cell RNA sequencing identifies platelet-biased human bone marrow HSCs.

cell biology↗

bioRxiv2021

SBP-SITA: A sequence-based prediction tools for S-itaconation

As a recently-reported post-translational modification, S-itaconation plays an important role in inflammation suppression. In order to understand its regulatory mechanism in many life activities, the essential step is the recognition of S-itaconation. However, it is difficult to identify S-itaconation in the proteome for the high cost, which limits further investigation. In this study, we constructed an ensemble algorithm based on Soft Voting Classifier. The area under the ROC curve (AUC) value 0.73 for ensemble model. Accordingly, we constructed the on-line prediction tool dubbed SBP-SITA for easily identifying Cystine sites. SBP-SITA is available at http://www.bioinfogo.org/sbp-sita.

bioinformatics↗

bioRxiv2021

Repression of MAPK/Erk signaling by Efnb2-Ephb4-Rasa1 is required for lymphatic valve formation

The lymphatic vascular system plays important roles in various physiological and pathological processes, and lack of lymphatic or lymphovenous valves always causes lymph or blood reflux, and can lead to lymphedema. However, the molecular mechanism underlying the valve formation is poorly understood. Here we report that the MAPK/Erk signaling needs to be repressed during the valve-forming lymphatic endothelial cells (LECs) fate determination, which differs from its positive role in the LECs specification. Up-regulation of MAPK/Erk signaling in ephb4b, efnb2a;efnb2b and rasa1a;rasa1b mutants leads to lymphatic valve defects, whereas simultaneous loss of Erk1 and Erk2 causes valve hyperplasia. Moreover, valve defects in ephb4b or rasa1a;rasa1b mutants are mitigated in the presence of MEK inhibitors, indicating a new function of Efnb2-Ephb4-Rasa1 cassette in lymphatic valve progenitor cells specification by repressing MAPK/Erk activity. Therefore, our findings provide a mechanistic understanding of the lymphatic valve formation and potential drug targets for related lymphatic diseases.

developmental biology↗

bioRxiv2021

Elevated transcriptional pausing of RNA polymerase II underlies acquired resistance to radiotherapy

As the mainstay modality for many malignancies, particularly inoperable solid tumors such as nasopharyngeal carcinoma (NPC), ionizing radiation (IR) induces a variety of lesions in genomic DNA, evoking a multipronged DNA damage response to interrupt many cellular processes including transcription. The turbulence in transcription, depending on the nature of DNA lesions, encompasses local blockage of RNA polymerase II (RNAPII) near the damage sites, as well as a less understood genome-wide alteration. How the transcriptional change influences the effectiveness of radiotherapy remains unclear. Using a panel of NPC and lung cancer cell lines, we observe increased phosphorylation at serine 5 (pS5) of the RNAPII after IR, indicating an accumulation of paused RNAPII. Remarkably, a similar increase of pS5 is seen in IR-resistant cells. ChIP-seq analysis of RNAPII distribution confirms this increased pausing both in IR-treated and IR-resistant NPC cells, notably on genes involved in radiation response and cell cycle. Accordingly, many of these genes show downregulated transcripts abundance in IR-resistant cells, and individual knockdown some of them such as TP53 and NEK7 endows NPC cells with varying degrees of IR-resistance. Decreasing pS5 of RNAPII and hence tuning down transcriptional pausing by inhibiting CDK7 reverses IR-resistance both in cell culture and xenograft models. Our results therefore uncover an unexpected link between elevated transcriptional pausing and IR-resistance. Given the recurrent NPC tissues display a steady increase in pS5 compared to the paired primary tissues, we suggest that CDK7 inhibitors can be used in combination with radiotherapy to increase sensitivity and thwart resistance.

cancer biology↗

bioRxiv2021

Drought restricted sucrose transport from outer cottonseed coat to fiber and further inhibited cellulose synthesis during cotton fiber thickening

The formation of cotton fiber strength largely relies on continuous and steady sucrose supply to cellulose synthesis and is greatly impaired by drought. However, the effects of drought on sucrose import into fiber and its involvement in cellulose biosynthesis within fiber remain unclear. To end this, moisture deficiency experiments were conducted using two Gossypium hirsutum cultivars of Dexiamian 1 (drought-tolerant) and Yuzaomian 9110 (drought-sensitive). Fiber strength was significantly decreased under drought. The results of 13C isotope labeling indicated that drought notably reduced sucrose efflux from cottonseed coat to fiber, and this was caused by down-regulation of sucrose transporter genes (GhSWEET10 and GhSWEET15) in the outer cottonseed coat, finally leading to decreased sucrose accumulation in fiber. Further, under drought, the balance of sucrose allocation within fiber was disrupted by increasing the flow of sucrose into {beta}-1,3-glucan synthesis and lignin synthesis but hindering that into cellulose synthesis in both cultivars. Additionally, glycolysis and starch synthesis were specifically enhanced by drought in Yuzaomian 9110, which further reduced the flow of sucrose into cellulose synthesis. Under drought, the cellulose deposition was decreased due to promoted cellulose degrading process in Dexiamian 1 and stunted cellulose synthesis in Yuzaomian 9110. Consequently, reduced cellulose content was measured in drought-stressed fibers for both cultivars. In summary, the inhibited cellulose accumulation caused by drought was mainly due to reduced sucrose translocation from the outer cottonseed coat to fiber, and less sucrose partitioned to cellulose synthesis pathway under the condition of intensified competition for sucrose by different metabolic pathways within fiber, finally degrading the fiber strength. HighlightThis article revealed the path of sucrose flow from cottonseed coat to cotton fiber and sucrose competition patterns within cotton fiber under drought and their relationships with fiber strength loss.

plant biology↗

bioRxiv2021

The exosomes derived from urine of premature infants target MAPK8 via miR-30a-5p to protect cisplatin-induced acute kidney injury in mice

AimAcute kidney injury (AKI), a global public health issue, not only causes millions of deaths every year, but is also a susceptible factor for chronic kidney disease (CKD). Nephrotoxic drugs are an important cause of AKI. There is still a lack of effective and satisfactory prevention method in clinical practice. This study investigated the protective effect of the exosomes derived from urine of premature infants on cisplatin-induced acute kidney injury. MethodsIsolation of exosomes from fresh urine of premature infants: The characteristics of exosomes were determined by flow cytometry, transmission electron microscopy and Western blotting. A C57BL/6 mice model of cisplatin-induced acute kidney injury was established. The mice in the experimental group were given 100ug exosomes dissolved in 200ul solution. The mice in the control group were given normal saline (200ul). These treatments were performed 24 hours after AKI was induced by intraperitoneal injection of cisplatin. To evaluate renal function, blood was drawn 24 hours after AKI model was established and serum creatinine (sCr) was measured. The mice were euthanized 72 hours after exosome treatment. The kidneys were collected for pathological examination, RNA and protein extraction, and the evaluation of renal tubular damage and apoptosis. In the in-vitro experiment, human renal cortex/proximal tubular cells (HK2) was induced by cisplatin to assess the protective ability of the exosomes derived from urine of premature infants. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western Blotting were used to evaluate the effect of exosomes treatment on the apoptosis of HK2 cells induced by cisplatin. Exosome microRNA sequencing technology and bioinformatics analysis method were applied to investigate the miRNAs enriched in exosomes and their target genes. The dual luciferase gene reporter system was used to detect the interaction of target genes. ResultsTreatment of exosomes derived from urine of premature infants could decrease the level of serum creatinine and the apoptosis of renal tubular cell, inhibit the infiltration of inflammatory cell, protect mice from acute kidney injury induced by cisplatin and reduce mortality. In addition, miR-30a-5p was the most abundant miRNA in the exosomes derived from urine of premature infants. It protected HK2 cells from cisplatin-induced apoptosis by targeting and down-regulating the 3UTR of mitogen-activated protein kinases (MAPK8) mRNA. ConclusionsAccording to our results, the exosomes derived from urine of premature infants alleviated cisplatin-induced acute kidney injury in mice and inhibited the apoptosis of human proximal tubular cells (HK2) induced by cisplatin in vitro. MiR-30a-5p in exosomes inhibited cisplatin-induced MAPK activation, ameliorated apoptosis, and protected renal function. The exosomes derived from urine of premature infants provided a promising acellular therapy for AKI.

molecular biology↗