OPEN STOMATA 1 phosphorylates CYCLIC NUCLEOTIDE-GATED CHANNELs to trigger Ca2+ signaling for abscisic acid-induced stomatal closure in Arabidopsis.

Multiple cyclic nucleotide-gated channels (CNGCs) are abscisic acid (ABA)-activated Ca2+ channels in Arabidopsis (Arabidopsis thaliana) guard cells. In particular, CNGC5, CNGC6, CNGC9, and CNGC12 are essential for ABA-specific cytosolic Ca2+ signaling and stomatal movements. However, the mechanisms underlying ABA-mediated regulation of CNGCs and Ca2+ signaling are still unknown. In this study, we identified the Ca2+-independent protein kinase OPEN STOMATA 1 (OST1) as a CNGC activator in Arabidopsis. OST1-targeted phosphorylation sites were identified in CNGC5, CNGC6, CNGC9, and CNGC12. These CNGCs were strongly inhibited by Ser-to-Ala mutations and fully activated by Ser-to-Asp mutations at the OST1-targeted sites. The overexpression of individual inactive CNGCs (iCNGCs) under the UBIQUITIN10 promoter in wild-type Arabidopsis conferred a strong dominant-negative-like ABA-insensitive stomatal closure phenotype. In contrast, expressing active CNGCs (aCNGCs) under their respective native promoters in the cngc5-1 cngc6-2 cngc9-1 cngc12-1 quadruple mutant fully restored ABA-activated cytosolic Ca2+ oscillations and Ca2+ currents in guard cells, and rescued the ABA-insensitive stomatal movement mutant phenotypes. Thus, we uncovered that ABA elicits cytosolic Ca2+ signaling via an OST1-CNGC module, in which OST1 functions as a convergence point of the Ca2+-dependent and -independent pathways in Arabidopsis guard cells.

Multiple cyclic nucleotide-gated channels function as ABA-activated Ca2+ channels required for ABA-induced stomatal closure in Arabidopsis.

Abscisic acid (ABA)-activated inward Ca2+-permeable channels in the plasma membrane (PM) of guard cells are required for the initiation and regulation of ABA-specific cytosolic Ca2+ signaling and stomatal closure in plants. But the identities of the PM Ca2+ channels are still unknown. We hypothesized that the ABA-activated Ca2+ channels consist of multiple CYCLIC NUCLEOTIDE-GATED CHANNEL (CNGC) proteins from the CNGC family, which is known as a Ca2+-permeable channel family in Arabidopsis (Arabidopsis thaliana). In this research, we observed high expression of multiple CNGC genes in Arabidopsis guard cells, namely CNGC5, CNGC6, CNGC9, and CNGC12. The T-DNA insertional loss-of-function quadruple mutant cngc5-1 cngc6-2 cngc9-1 cngc12-1 (hereafter c5/6/9/12) showed a strong ABA-insensitive phenotype of stomatal closure. Further analysis revealed that ABA-activated Ca2+ channel currents were impaired, and ABA-specific cytosolic Ca2+ oscillation patterns were disrupted in c5/6/9/12 guard cells compared with in wild-type guard cells. All ABA-related phenotypes of the c5/6/9/12 mutant were successfully rescued by the expression of a single gene out of the four CNGCs under the respective native promoter. Thus, our findings reveal a type of ABA-activated PM Ca2+ channel comprising multiple CNGCs, which is essential for ABA-specific Ca2+ signaling of guard cells and ABA-induced stomatal closure in Arabidopsis.

Quantification and Proteomic Characterization of ß-Hydroxybutyrylation Modification in the Hearts of AMPKα2 Knockout Mice.

AMP-activated protein kinase alpha 2 (AMPKα2) regulates energy metabolism, protein synthesis, and glucolipid metabolism myocardial cells. Ketone bodies produced by fatty acid ß-oxidation, especially ß-hydroxybutyrate, are fatty energy-supplying substances for the heart, brain, and other organs during fasting and long-term exercise. They also regulate metabolic signaling for multiple cellular functions. Lysine ß-hydroxybutyrylation (Kbhb) is a ß-hydroxybutyrate-mediated protein posttranslational modification. Histone Kbhb has been identified in yeast, mouse, and human cells. However, whether AMPK regulates protein Kbhb is yet unclear. Hence, the present study explored the changes in proteomics and Kbhb modification omics in the hearts of AMPKα2 knockout mice using a comprehensive quantitative proteomic analysis. Based on mass spectrometry (LC-MS/MS) analysis, the number of 1181 Kbhb modified sites in 455 proteins were quantified between AMPKα2 knockout mice and wildtype mice; 244 Kbhb sites in 142 proteins decreased or increased after AMPKα2 knockout (fold change >1.5 or <1/1.5, p < 0.05). The regulation of Kbhb sites in 26 key enzymes of fatty acid degradation and tricarboxylic acid cycle was noted in AMPKα2 knockout mouse cardiomyocytes. These findings, for the first time, identified proteomic features and Kbhb modification of cardiomyocytes after AMPKα2 knockout, suggesting that AMPKα2 regulates energy metabolism by modifying protein Kbhb.

Biosynthesis and Assembly Logic of Fungal Hybrid Terpenoid Natural Products.

In recent decades, fungi have emerged as significant sources of diverse hybrid terpenoid natural products, and their biosynthetic pathways are increasingly unveiled. This review mainly focuses on elucidating the various strategies underlying the biosynthesis and assembly logic of these compounds. These pathways combine terpenoid moieties with diverse building blocks including polyketides, nonribosomal peptides, amino acids, p-hydroxybenzoic acid, saccharides, and adenine, resulting in the formation of plenty of hybrid terpenoid natural products via C-O, C-C, or C-N bond linkages. Subsequent tailoring steps, such as oxidation, cyclization, and rearrangement, further enhance the biological diversity and structural complexity of these hybrid terpenoid natural products. Understanding these biosynthetic mechanisms holds promise for the discovery of novel hybrid terpenoid natural products from fungi, which will promote the development of potential drug candidates in the future.

Distinct characteristics of the gut virome in patients with osteoarthritis and gouty arthritis.

BACKGROUND/PURPOSE(S): The gut microbiota and its metabolites play crucial roles in pathogenesis of arthritis, highlighting gut microbiota as a promising avenue for modulating autoimmunity. However, the characterization of the gut virome in arthritis patients, including osteoarthritis (OA) and gouty arthritis (GA), requires further investigation. METHODS: We employed virus-like particle (VLP)-based metagenomic sequencing to analyze gut viral community in 20 OA patients, 26 GA patients, and 31 healthy controls, encompassing a total of 77 fecal samples. RESULTS: Our analysis generated 6819 vOTUs, with a considerable proportion of viral genomes differing from existing catalogs. The gut virome in OA and GA patients differed significantly from healthy controls, showing variations in diversity and viral family abundances. We identified 157 OA-associated and 94 GA-associated vOTUs, achieving high accuracy in patient-control discrimination with random forest models. OA-associated viruses were predicted to infect pro-inflammatory bacteria or bacteria associated with immunoglobulin A production, while GA-associated viruses were linked to Bacteroidaceae or Lachnospiraceae phages. Furthermore, several viral functional orthologs displayed significant differences in frequency between OA-enriched and GA-enriched vOTUs, suggesting potential functional roles of these viruses. Additionally, we trained classification models based on gut viral signatures to effectively discriminate OA or GA patients from healthy controls, yielding AUC values up to 0.97, indicating the clinical utility of the gut virome in diagnosing OA or GA. CONCLUSION: Our study highlights distinctive alterations in viral diversity and taxonomy within gut virome of OA and GA patients, offering insights into arthritis etiology and potential treatment and prevention strategies.

PagKNAT2/6b promotes shoot branching by attenuating auxin-strigolactone signalling in poplar.

Shoot branching from axillary bud (AB) directly determines plant architecture. However, the mechanism through which AB remains dormant or emerges to form branches as plants grow remains largely unknown. Here, the auxin-strigolactone (IAA-SL) pathway was first shown to regulate shoot branching in poplar, and we found that PagKNAT2/6b could modulate this pathway. PagKNAT2/6b was expressed mainly in the shoot apical meristem and AB and was induced by shoot apex damage. PagKNAT2/6b overexpressing poplar plants (PagKNAT2/6b OE) exhibited multiple branches that mimicked the branching phenotype of nontransgenic plants after decapitation treatment, while compared with nontransgenic controls, PagKNAT2/6b antisense transgenic poplar and Pagknat2/6b mutant lines exhibited a significantly decreased number of branches after shoot apex damage treatment. In addition, we found that PagKNAT2/6b directly inhibits the expression of the key IAA synthesis gene PagYUC6a, which is specifically expressed in the shoot apex. Moreover, overexpression of PagYUC6a in the PagKNAT2/6b OE background reduced the number of branches after shoot apex damage treatment. Overall, we conclude that PagKNAT2/6b responds to shoot apical injury and regulates shoot branching through the IAA-SL pathway. These findings may provide a theoretical basis and candidate genes for genetic engineering to create new forest tree species with different crown types.

Minisci-Type Dehydrogenative Coupling of N-Heteroaromatic Rings with Inert C(sp3)-H Enabled by a Visible-Light-Catalyzed Intermolecular Hydrogen Atom Transfer Process.

The Minisci-type dehydrogenative coupling of N-heteroaromatic rings with inert C-H or Si-H partners via visible-light-catalyzed hydrogen atom transfer has been reported. This methodology allows the coupling reactions to be carried out in water as a solvent under air atmospheric conditions with visible-light illumination. A wide range of inert C-H and Si-H partners could be directly coupled with various N-aromatic heterocycles to deliver products in good to excellent yields.

Circular RNAs: emerging players in brain aging and neurodegenerative diseases.

Brain aging is closely related to neurodegenerative diseases. Circular RNAs (circRNAs) are a type of conserved RNAs with covalently closed continuous loops. Emerging evidence has shown that circRNAs are implicated in the biology of brain aging and the pathology of age-related neurodegenerative diseases. Here, we summarize current studies on circRNAs associated with brain aging and neurodegenerative diseases by discussing their expression features, pathophysiological roles, and mechanisms of action. We also discuss the potential challenges of circRNA-based therapy against brain aging and neurodegenerative diseases, as well as their potential as diagnostic biomarkers of neurodegenerative diseases. The review provides insights into current progress in the functions of circRNAs in the process of brain aging and neurodegenerative diseases. © 2022 The Pathological Society of Great Britain and Ireland.

Effectiveness of electroacupuncture on postoperative ileus prevention after abdominal surgery: A systematic review and trial sequential analysis of randomized controlled trials.

BACKGROUND: We aimed to verify the effectiveness of electroacupuncture on postoperative ileus prevention after abdominal surgery by meta-analysis and trial sequential analysis (TSA). METHODS: From inception to May 14, 2024, PubMed, the Cochrane Library, Web of Science, and Embase databases were searched. TSA was used to determine an optimal sample size and control false-positive findings. The primary outcome was the time to first defecation (hours). RESULTS: Fourteen studies were included, with 1105 participants. Meta-analysis and TSA revealed firm evidence for benefits that electroacupuncture shorted the time to first defecation (mean difference [MD] -12.73 h, I2 = 22%, P < 0.01), the time to first flatus (MD -7.03 h, I2 = 25%, P < 0.01), the time to start of sips of water (MD -12.02 h, I2 = 0%, P < 0.01), and the time to start of liquid diet (MD -12.97 h, I2 = 0%, P < 0.01) compared with usual care. While compared with sham electroacupuncture, meta-analysis and TSA also confirmed that electroacupuncture shortened the time to first defecation (MD -10.81 h, I2 = 31%, P = 0.02) and the time to first flatus (MD -10.81 h, I2 = 0%, P < 0.01). However, TSA revealed that firm evidence for benefit or futility was not reached for the length of hospital stay and the rates of postoperative prolonged ileus. CONCLUSIONS: Electroacupuncture shortened the duration of postoperative ileus in patients undergoing abdominal surgery, and the adverse events related to electroacupuncture were minor. Further investigation of the effect of electroacupuncture on the risk of prolonged postoperative ileus is warranted in the future.

NGEF is a potential prognostic biomarker and could serve as an indicator for immunotherapy and chemotherapy in lung adenocarcinoma.

BACKGROUND: Neuronal guanine nucleotide exchange factor (NGEF) plays a key role in several cancers; however, its role in lung adenocarcinoma (LUAD) remains unclear. The aim of this study was to evaluate the efficacy of NGEF as a prognostic biomarker and potential therapeutic target for LUAD. METHODS: NGEF expression data for multiple cancers and LUAD were downloaded from multiple databases. The high- and low-NGEF expression groups were constructed based on median NGEF expression in LUAD samples, and then performed Kaplan-Meier survival analysis. Differentially expressed genes (DEGs) from the two NGEF expression groups were screened and applied to construct a protein-protein interaction network. The primary pathways were obtained using gene set enrichment analysis. The associations between NGEF expression and clinical characteristics, immune infiltration, immune checkpoint inhibitors (ICIs), sensitivity to chemotherapy, and tumor mutation burden (TMB) were investigated using R. Levels of NGEF expression in the lung tissue was validated using single-cell RNA sequencing, quantitative polymerase chain reaction (qPCR), immunohistochemical staining, and western blot analysis. RESULTS: The expression of NGEF mRNA was upregulated in multiple cancers. mRNA and protein expression levels of NGEF were higher in patients with LUAD than in controls, as validated using qPCR and western blot. High NGEF expression was an independent prognostic factor for LUAD and was associated with advanced tumor stage, large tumor size, more lymph node metastasis, and worse overall survival (OS). A total of 182 overlapping DEGs were screened between The Cancer Genome Atlas and GSE31210, among which the top 20 hub genes were identified. NGEF expression was mainly enriched in the pathways of apoptosis, cell cycle, and DNA replication. Moreover, elevated NGEF expression were associated with a high fraction of activated memory CD4+ T cells and M0 macrophages; elevated expression levels of the ICIs: programmed cell death 1 and programmed cell death 1 ligand 1 expression; higher TMB; and better sensitivity to bortezomib, docetaxel, paclitaxel, and parthenolide, but less sensitivity to axitinib and metformin. CONCLUSION: NGEF expression is upregulated in LUAD and is significantly associated with tumor stages, OS probability, immune infiltration, immunotherapy response, and chemotherapy response. NGEF may be a potential diagnostic and prognostic biomarker and therapeutic target in LUAD.

Elevated NOX4 promotes tumorigenesis and acquired EGFR-TKIs resistance via enhancing IL-8/PD-L1 signaling in NSCLC.

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have been widely used for human non-small-cell lung cancer (NSCLC) treatment. However, acquired resistance to EGFR-TKIs is the major barrier of treatment success, and new resistance mechanism remains to be elucidated. In this study, we found that elevated NADPH oxidase 4 (NOX4) expression was associated with acquired EGFR-TKIs resistance. Gefitinib is the first-generation FDA-approved EGFR-TKI, and osimertinib is the third-generation FDA-approved EGFR-TKI. We demonstrated that NOX4 knockdown in the EGFR-TKI resistant cells enabled the cells to become sensitive to gefitinib and osimertinib treatment, while forced expression of NOX4 in the sensitive parental cells was sufficient to induce resistance to gefitinib and osimertinib in the cells. To elucidate the mechanism of NOX4 upregulation in increasing TKIs resistance, we found that knockdown of NOX4 significantly down-regulated the expression of transcription factor YY1. YY1 bound directly to the promoter region of IL-8 to transcriptionally activate IL-8 expression. Interestingly, knockdown of NOX4 and IL-8 decreased programmed death ligand 1 (PD-L1) expression, which provide new insight on TKIs resistance and immune escape. We found that patients with higher NOX4 and IL-8 expression levels showed a shorter survival time compared to those with lower NOX4 and IL-8 expression levels in response to the anti-PD-L1 therapy. Knockdown of NOX4, YY1 or IL-8 alone inhibited angiogenesis and tumor growth. Furthermore, the combination of NOX4 inhibitor GKT137831 and gefitinib had synergistic effect to inhibit cell proliferation and tumor growth and to increase cellular apoptosis. These findings demonstrated that NOX4 and YY1 were essential for mediating the acquired EGFR-TKIs resistance. IL-8 and PD-L1 are two downstream targets of NOX4 to regulate TKIs resistance and immunotherapy. These molecules may be used as potential new biomarkers and therapeutic targets for overcoming TKIs resistance in the future.

Long-term exposure to air pollutants and new-onset migraine: A large prospective cohort study.

BACKGROUNDS: Short-term exposure to air pollutants increases the risk of migraine, but the long-term impacts of exposure to multiple pollutants on migraine have not been established. The aim of this large prospective cohort study was to explore these links. METHODS: A total of 458,664 participants who were free of migraine at baseline from the UK Biobank were studied. Cox proportional hazards models were used to estimate the risk of new-onset migraine from combined long-term exposure to four pollutants, quantified as an air pollution score using principal component analysis. RESULTS: During a median (IQR) follow-up of 12.5 (11.8, 13.2) years, a total of 5417 new-onset migraine cases were documented. Long-term exposure to multiple air pollutants was associated with an increased risk of new-onset migraine, as indicated by an increased in the SDs of PM2.5 (hazard ratio (HR): 1.04, 95% CI: 1.01-1.06, P = 0.009), PM10 (HR: 1.07, 95% CI: 1.04-1.10, P < 0.001), NO2 (HR: 1.10, 95% CI: 1.07-1.13, P < 0.001) and NOx (HR: 1.04, 95% CI: 1.01-1.07, P = 0.005) in the main model. The air pollution score showed a doseresponse association with an increased risk of new-onset migraine. Similarly, compared with those of the lowest tertile, the HRs (95% CI) of new-onset migraine were 1.11 (95% CI: 1.04-1.19, P = 0.002) and 1.17 (95% CI: 1.09-1.26, P < 0.001) in tertiles 2 and 3, respectively, according to the main model (P trend < 0.001). CONCLUSION: Long-term individual and joint exposure to multiple air pollutants is associated with an increased risk of new-onset migraine.

Chlorogenic acid improves the development of porcine parthenogenetic embryos by regulating oxidative stress and ameliorating mitochondrial function.

Chlorogenic acid (CGA) is an effective phenolic antioxidant that can scavenge hydroxyl radicals and superoxide anions. Herein, the protective effects and mechanisms leading to CGA-induced porcine parthenogenetic activation (PA) in early-stage embryos were investigated. Our results showed that 50 µM CGA treatment during the in vitro culture (IVC) period significantly increased the cleavage and blastocyst formation rates and improved the blastocyst quality of porcine early-stage embryos derived from PAs. Then, genes related to zygotic genome activation (ZGA) were identified and investigated, revealing that CGA can promote ZGA in porcine PA early-stage embryos. Further analysis revealed that CGA treatment during the IVC period decreased the abundance of reactive oxygen species (ROS), increased the abundance of glutathione and enhanced the activity of catalase and superoxide dismutase in porcine PA early-stage embryos. Mitochondrial function analysis revealed that CGA increased mitochondrial membrane potential and ATP levels and upregulated the mitochondrial homeostasis-related gene NRF-1 in porcine PA early-stage embryos. In summary, our results suggest that CGA treatment during the IVC period helps porcine PA early-stage embryos by regulating oxidative stress and improving mitochondrial function.

The effects of 17α-methyltestosterone on gonadal histology and gene expression along hypothalamic-pituitary-gonadal axis, germ cells, sex determination, and hypothalamus-pituitary-thyroid axis in zebrafish (Danio rerio).

As a synthetic androgen, 17α-methyltestosterone (MT) is widely used in aquaculture to induce sex reversal and may pose a potential risk to aquatic organisms. This ecological risk has attracted the attention of many scholars, but it is not comprehensive enough. Thus, the adverse effects of MT on zebrafish (Danio rerio) were comprehensively evaluated from gonadal histology, as well as the mRNA expression levels of 47 genes related to hypothalamic-pituitary-gonadal (HPG) axis, germ cell differentiation, sex determination, and hypothalamus-pituitary-thyroid (HPT) axis. Adult zebrafish with a female/male ratio of 5:7 were exposed to a solvent control (0.001% dimethyl sulfoxide) and three measured concentrations of MT (5, 51 and 583 ng/L) for 50 days. The results showed that MT had no significant histological effects on the ovaries of females, but the frequency of late-mature oocytes (LMO) showed a downward trend, indicating that MT could induce ovarian suppression to a certain extent. The transcriptional expression of activating transcription factor 4b1 (atf4b1), activating transcription factor 4b2 (atf4b2), calcium/calmodulin-dependent protein kinase II delta 1 (camk2d1), calcium/calmodulin-dependent protein kinase II delta 2 (camk2d2) and calcium/calmodulin-dependent protein kinase II inhibitor 2 (camk2n2) genes in the brain of females increased significantly at all treatment groups of MT, and the mRNA expression of forkhead box L2a (foxl2) and ovarian cytochrome P450 aromatase (cyp19a1a) genes in the ovaries were down-regulated by 5 and 583 ng/L group, which would translate into inhibition of oocyte development. As compared to females, MT had relatively little effects on the reproductive system of males, and only the transcriptional alterations of synaptonemal complex protein 3 (sycp3) and 17-alpha-hydroxylase/17,20-lyase (cyp17) genes were observed in the testes, not enough to affect testicular histology. In addition, MT at all treatments strongly increased corticotropin-releasing hormone (crh) transcript in the brain of females, as well as deiodinase 2 (dio2) transcript in the brain of males. The paired box protein 8 (pax8) gene was significantly decreased at 51 or 583 ng/L of MT in both female and male brains. The above results suggest that MT can pose potential adverse effects on the reproductive and thyroid endocrine system of fish.

Design, synthesis, and anti-tumor activity of derivatives of ring A and C-28 of asiatic acid.

Based on computer-aided drug design (CADD), the active groups of the known active small molecule compounds that can bind to EGFR target protein were analyzed through the molecular docking method. Then, 12 novel asiatic acid derivatives were synthesized by introducing active groups at ring A and C-28 positions of asiatic acid. The structures of these novel compounds were determined by NMR and MS. Furthermore, the anti-tumor activities of these derivatives on human lung cancer cells (A549) and human breast cancer cells (MCF-7) were evaluated by MTT assay. In conclusion, compounds I4 and II3 have stronger anti-cancer activity than parent compounds, the activities were stronger than gefitinib and comparable to afatinib, which may be potential candidate compounds for tumor therapy.

[Mechanism of tetramethylpyrazine intervention with ischemia-reperfusion rats based on Nrf2/HO-1/CXCR4 pathway through regulating neural stem cell migration].

This study aims to decipher the mechanism of tetramethylpyrazine(TMP) in regulating the migration of neural stem cells(NSCs) in the rat model of middle cerebral artery occlusion(MCAO) via the nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase 1(HO-1)/C-X-C motif chemokine receptor 4(CXCR4) pathway. SD rats were randomized into sham, MCAO(model), and tetramethylpyrazine(TMP, 20 mg·kg~(-1) and 40 mg·kg~(-1)) groups. The neurological impairment was assessed by the modified neurological severity score(mNSS). The immunofluorescence assay was employed to detect the cells stained with both 5-bromodeoxyuridine(BrdU) and doublecortin(DCX) in the brain tissue. The effect of TMP on the migration of C17.2 cells was observed. Western blot was employed to determine the protein levels of Nrf2, HO-1, p62, NAD(P)H quinone oxidoreductase 1(NQO1), stromal cell-derived factor 1(SDF-1), and CXCR4 in the brain tissue and C17.2 cells. The results showed that after 7 days and 21 days of mode-ling, the mNSS and BrdU~+/DCX~+ cells were increased, and the expression of Nrf2 and CXCR4 in the brain tissue was up-regulated. Compared with the model group, TMP(40 mg·kg~(-1)) reduced the mNSS, increased the number of BrdU~+/DCX~+ cells, and up-regulated the expression of Nrf2, CXCR4, and SDF-1. In addition, TMP promoted the migration of C17.2 cells and up-regulated the expression of p62, Nrf2, HO-1, and NQO1 in a time-and dose-dependent manner. The expression was the highest at the time point of 12 h in the TMP(50 µg·mL~(-1)) group(P<0.01). In conclusion, TMP activates the Nrf2/HO-1/CXCR4 pathway to promote the migration of NSCs to the ischemic area, thus exerting the therapeutic effect on the ischemia-reperfusion injury. This study provides experimental support for the application of TMP in ischemic stroke.

[Mechanism of tetramethylpyrazine combined with neural stem cells transplantation on cerebral ischemia-reperfusion rats].

This study aimed to investigate the intervention effect of tetramethylpyrazine(TMP) combined with transplantation of neural stem cells(NSCs) on middle cerebral artery occlusion(MCAO) rat model and to explore the mechanism of TMP combined with NSCs transplantation on ischemic stroke based on the regulation of stem cell biological behavior. MCAO rats were randomly divided into a model group, a TMP group, an NSCs transplantation group, and a TMP combined with NSCs transplantation group according to neurological function scores. A sham group was set up at the same time. The neurological function score was used to evaluate the improvement of neurological function in MCAO rats after TMP combined with NSCs transplantation. The proliferation, migration, and differentiation of NSCs were evaluated by BrdU, BrdU/DCX, BrdU/NeuN, and BrdU/GFAP immunofluorescence labeling. The protein expression of stromal cell-derived factor 1(SDF-1), C-X-C motif chemokine receptor 4(CXCR4), as well as oxidative stress pathway proteins nuclear factor erythroid 2-related factor 2(Nrf2), Kelch-like ECH-associated protein 1(KEAP1), heme oxygenase 1(HO-1), NAD(P)H quinone oxidoreductase 1(NQO1) was detected by Western blot to study the migration mechanism of TMP combined with NSCs. The results showed that TMP combined with NSCs transplantation significantly improved the neurological function score in MCAO rats. Immunofluorescence staining showed a significant increase in the number of BrdU~+, BrdU~+/DCX~+, BrdU~+/NeuN~+, and BrdU~+/GFAP~+ cells in the TMP, NSCs transplantation, and combined treatment groups, with the combined treatment group showing the most significant increase. Further Western blot analysis revealed significantly elevated expression of CXCR4 protein in the TMP, NSCs transplantation, and combined treatment groups, along with up-regulated protein expression of Nrf2, HO-1, and NQO1, and decreased KEAP1 protein expression. This study showed that both TMP and NSCs transplantation can promote the recovery of neurological function by promoting the proliferation, migration, and differentiation of NSCs, and the effect of TMP combined with NSCs transplantation is superior. The mechanism of action may be related to the activation of the Nrf2/HO-1/CXCR4 pathway.

O-Fucosylation of BMP1 promotes endometrial decidualization by activating BMP/Smad signaling pathway.

Endometrial decidualization is critical to successful uterine receptivity and embryo implantation. Dysfunction of decidualization is associated with some pregnancy-related disorders, including miscarriage. Protein glycosylation is involved in many physiological and pathological processes. Protein O-fucosyltransferase 1 (poFUT1) is a key enzyme responsible for O-fucosylation biosynthesis on glycoproteins. Bone morphogenetic protein 1 (BMP1) is an essential glycoprotein in reproduction. However, the role and molecular mechanism of fucosylated BMP1 in endometrial stromal cell decidualization are still unknown. In the current study, we found that BMP1 contains a potential O-fucosylation site. Moreover, poFUT1 and BMP1 levels in the secretory phase are higher than those in the proliferative phase, and the highest level was observed in the human uterine tissues of early pregnancy, while a decrease of poFUT1 and BMP1 in the decidua was observed in miscarriage patients. Using human endometrial stromal cells (hESCs), we demonstrated that O-fucosylation of BMP1 was elevated after induced decidualization. Moreover, the increase of BMP1 O-fucosylation by poFUT1 promoted BMP1 secretion to the extracellular matrix, and more actively binds to CHRD. The binding of BMP1 and CHRD further released BMP4 originally bound to CHRD, and activated BMP/Smad signaling pathway, thereby accelerating the decidualization of human endometrial stromal cells. In summary, these results suggest that BMP1 O-fucosylation by poFUT1 could be a potential diagnostic and therapeutic target to predict miscarriage in early pregnancy examinations.

Role of poFUT1 and O-fucosylation in placental angiogenesis†.

Trophoblast cells are critical to placental angiogenesis in the first trimester of pregnancy. Dysfunction of trophoblast leads to defective vascular remodeling and impaired angiogenesis, which is believed as the major cause of placental insufficiency and pregnancy failure. Protein O-fucosyltransferase 1 (poFUT1) is mainly responsible for O-fucosylated glycan biosynthesis on glycoproteins, and poFUT1 deficiency causes embryonic lethality in mice. However, the expression and function of poFUT1 in trophoblast-mediated human placental vessel formation remain unclear. In the current study, we showed that fewer blood vessels were observed in the villi and decidua of miscarriage patients than in normal pregnancy women. The expression of poFUT1 was decreased in the trophoblast cells of miscarriage patients compared with normal pregnancy women. Employing HTR/SVneo cells and an in vivo chorioallantoic membrane assay, we demonstrated that poFUT1 promoted the proliferation, migration ability, and angiogenesis potential of trophoblast cells. The results also indicated that poFUT1 upregulated O-fucosylation on uPA, facilitated the binding of uPA and uPAR, activated the RhoA signaling pathway, and further enhanced the angiogenic capacity of trophoblast cells. Our study provides new evidence for a relationship between poFUT1/O-fucosylation and placental angiogenesis. These findings may provide potential diagnostic biomarkers and targeted therapies for miscarriage patients.

Highly Efficient Luminescence from a Red Thermally Activated Delayed Fluorescence Emitter with Flexible Conformation of Ancillary Groups.

Robust scaffolds were typically applied in thermally activated delayed fluorescence (TADF) molecules to suppress the non-radiative decay, trigger the fast spin-flipping, and enhance the light out-coupling efficiency. Herein, we disclosed for the first time the positive effect of flexible conformation of ancillary groups on the photophysical properties of TADF emitter. The red TADF emitter Ph-TPA with flexible conformation demonstrated small excited-state structural distortion and low reorganization energy compared to the counterpart Mc-TPA with a rigid macrocycle. Consequently, Ph-TPA showed an excellent photoluminescent quantum yield (PLQY) of 92 % and a state-of-the-art external quantum efficiency (EQE) of 30.6 % at 630 nm. This work could deepen our understanding of structure-property relationships of organic luminophores and help us to rationalize the design of efficient TADF materials.