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1.
Cell ; 156(4): 744-58, 2014 Feb 13.
Article in English | MEDLINE | ID: mdl-24529377

ABSTRACT

The clinical benefit conferred by vascular endothelial growth factors (VEGF)-targeted therapies is variable, and tumors from treated patients eventually reinitiate growth. Here, we identify a glycosylation-dependent pathway that compensates for the absence of cognate ligand and preserves angiogenesis in response to VEGF blockade. Remodeling of the endothelial cell (EC) surface glycome selectively regulated binding of galectin-1 (Gal1), which upon recognition of complex N-glycans on VEGFR2, activated VEGF-like signaling. Vessels within anti-VEGF-sensitive tumors exhibited high levels of α2-6-linked sialic acid, which prevented Gal1 binding. In contrast, anti-VEGF refractory tumors secreted increased Gal1 and their associated vasculature displayed glycosylation patterns that facilitated Gal1-EC interactions. Interruption of ß1-6GlcNAc branching in ECs or silencing of tumor-derived Gal1 converted refractory into anti-VEGF-sensitive tumors, whereas elimination of α2-6-linked sialic acid conferred resistance to anti-VEGF. Disruption of the Gal1-N-glycan axis promoted vascular remodeling, immune cell influx and tumor growth inhibition. Thus, targeting glycosylation-dependent lectin-receptor interactions may increase the efficacy of anti-VEGF treatment.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Neoplasms/blood supply , Neoplasms/drug therapy , Neovascularization, Pathologic , Vascular Endothelial Growth Factors/antagonists & inhibitors , Animals , Endothelial Cells/metabolism , Galectin 1/genetics , Galectin 1/metabolism , Glycosylation , Humans , Hypoxia , Mice , Receptors, Mitogen/metabolism
2.
Blood ; 142(14): 1219-1232, 2023 10 05.
Article in English | MEDLINE | ID: mdl-37467575

ABSTRACT

Diffuse large B-cell lymphoma (DLBCL) is a clinically and genetically heterogeneous disease with at least 5 recognized molecular subtypes. Cluster 5 (C5)/MCD tumors frequently exhibit concurrent alterations in the toll-like receptor (TLR) and B-cell receptor (BCR) pathway members, MYD88L265P and CD79B, and have a less favorable prognosis. In healthy B cells, the synergy between TLR and BCR signaling pathways integrates innate and adaptive immune responses and augments downstream NF-κB activation. In addition, physiologic TLR9 pathway engagement via MYD88, protein tyrosine kinase 2 (PYK2), and dedicator of cytokinesis 8 (DOCK8) increases proximal BCR signaling in healthy murine B cells. Although C5/MCD DLBCLs are selectively sensitive to Bruton tyrosine kinase (BTK) inhibition in in vitro studies and certain clinical trials, the role of mutated MYD88 in proximal BCR signaling remains undefined. Using engineered DLBCL cell line models, we found that concurrent MYD88L265P and CD79B alterations significantly increased the magnitude and duration of proximal BCR signaling, at the level of spleen tyrosine kinase and BTK, and augmented PYK2-dependent DOCK8 phosphorylation. MYD88L265P DLBCLs have significantly increased colocalization of DOCK8 with both MYD88 and the proximal BCR-associated Src kinase, LYN, in comparison with MYD88WT DLBCLs, implicating DOCK8 in MYD88L265P/proximal BCR cross talk. Additionally, DOCK8 depletion selectively decreased proximal BCR signaling, cellular proliferation, and viability of DLBCLs with endogenous MYD88L265P/CD79BY196F alterations and increased the efficacy of BTK blockade in these lymphomas. Therefore, MYD88L265P/DOCK8-enhanced proximal BCR signaling is a likely mechanism for the increased sensitivity of C5/MCD DLBCLs to BTK blockade.


Subject(s)
Lymphoma, Large B-Cell, Diffuse , Myeloid Differentiation Factor 88 , Animals , Humans , Mice , Focal Adhesion Kinase 2/metabolism , Guanine Nucleotide Exchange Factors/metabolism , Lymphoma, Large B-Cell, Diffuse/pathology , Myeloid Differentiation Factor 88/genetics , Myeloid Differentiation Factor 88/metabolism , Receptors, Antigen, B-Cell/metabolism , Signal Transduction , Toll-Like Receptors
3.
Biochem Biophys Res Commun ; 693: 149375, 2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38128243

ABSTRACT

BACKGROUND: Myocardial fibrosis (MF) is a common pathological condition in cardiovascular diseases that often causes severe cardiac dysfunction. MF is characterized by changes in cardiomyocytes, cardiac fibroblasts (CFs), levels of collagen (Col) -1, -3, and overdeposition of the extracellular matrix. Our previous research showed that leonurine (LE) effectively inhibits collagen synthesis and differentiation of CFs, but the mechanism is not fully elucidated. Recent evidence indicates that fat mass and obesity-associated proteins (FTO) regulates the occurrence and development of MF. This study aimed to explore the role of FTO in the antifibrotic effects of LE. METHODS: Neonatal rat CFs were isolated, and induced using angiotensin II (Ang II) to establish a cell model of MF. Cell viability, wound healing and transwell assays were used to detect cell activity and migration ability. The protein and mRNA levels of MF-related factors were measured following stimulation with Ang II and LE under normal conditions or after FTO knockdown. The RNA methylation level was measured by dot blot assay. RESULTS: The results showed that LE (20, 40 µM) was not toxic to normal CFs. LE reduced the proliferation, migration and collagen synthesis of Ang II-induced CFs. Further investigation showed that FTO was downregulated by Ang II stimulation, whereas LE reversed this effect. FTO knockdown facilitated the migration of CFs, upregulated the protein levels of Col-3, α-SMA and Col-1 in Ang II and LE-stimulated CFs, and enhanced the fluorescence intensity of α-SMA. Furthermore, LE reduced N6-methyladenosine (m6A) RNA methylation, which was partially blocked by FTO knockdown. FTO knockdown also reduced the expression levels of p53 protein in Ang II and LE-stimulated CFs. CONCLUSIONS: Our findings suggest that the inhibition of FTO may attenuate the antifibrotic effect of LE in CFs, suggesting that FTO may serve as a key protein for anti-MF of LE.


Subject(s)
Cardiomyopathies , Fibroblasts , Rats , Animals , Fibroblasts/metabolism , Cell Proliferation , Collagen Type I/genetics , Collagen Type I/metabolism , Myocytes, Cardiac/metabolism , Cardiomyopathies/pathology , Angiotensin II/pharmacology , Angiotensin II/metabolism , Myocardium/metabolism , Fibrosis , Cells, Cultured
4.
Haematologica ; 2024 Feb 22.
Article in English | MEDLINE | ID: mdl-38385251

ABSTRACT

Mutations in the master hematopoietic transcription factor GATA1 are often associated with functional defects in erythropoiesis and megakaryopoiesis. In this study, we identified a novel GATA1 germline mutation (c.1162delGG, p.Leu387Leufs*62) in a patient with congenital anemia and occasional thrombocytopenia. The C-terminal GATA1, a rarely studied mutational region, undergoes frameshifting translation as a consequence of this double-base deletion mutation. To investigate the specific function and pathogenic mechanism of this mutant, in vitro mutant models of stable re-expression cells were generated. The mutation was subsequently validated to cause diminished transcriptional activity of GATA1 and defective differentiation of erythroid and megakaryocytes. Using proximity labeling and mass spectrometry, we identified selective alterations in the proximal protein networks of the mutant, revealing decreased binding to a set of normal GATA1-interaction proteins, including the essential co-factor FOG1. Notably, our findings further demonstrated enhanced recruitment of the protein arginine methyltransferase PRMT6, which mediates histone modification at H3R2me2a and represses transcription activity. We also found an enhanced binding of this mutant GATA1/PRMT6 complex to the transcriptional regulatory elements of GATA1's target genes. Moreover, treatment of the PRMT6 inhibitor MS023 could partially rescue the inhibited transcriptional and impaired erythroid differentiation caused by the GATA1 mutation. Taken together, our results provide molecular insights into erythropoiesis in which mutation leads to partial loss of GATA1 function and the broader role of PRMT6 and its inhibitor MS023 in congenital anemia, highlighting PRMT6 binding as a negative factor of GATA1 transcriptional activity in aberrant hematopoiesis.

5.
Exp Cell Res ; 426(1): 113556, 2023 05 01.
Article in English | MEDLINE | ID: mdl-36933858

ABSTRACT

Overactivation of cardiac fibroblasts (CFs) is one of the main causes of myocardial fibrosis (MF), and inhibition of CF activation is a crucial strategy for MF therapy. A previous study by our group demonstrated that leonurine (LE) effectively inhibits collagen synthesis and myofibroblast generation originated from CFs, and eventually mitigates the progression of MF (where miR-29a-3p is likely to be a vital mediator). However, the underlying mechanisms involved in this process remain unknown. Thus, the present study aimed to investigate the precise role of miR-29a-3p in LE-treated CFs, and to elucidate the pharmacological effects of LE on MF. Neonatal rat CFs were isolated and stimulated by angiotensin II (Ang II) to mimic the pathological process of MF in vitro. The results show that LE distinctly inhibits collagen synthesis, as well as the proliferation, differentiation and migration of CFs, all of which could be induced by Ang II. In addition, LE promotes apoptosis in CFs under Ang II stimulation. During this process, the down-regulated expressions of miR-29a-3p and p53 are partly restored by LE. Either knockdown of miR-29a-3p or inhibition of p53 by PFT-α (a p53 inhibitor) blocks the antifibrotic effect of LE. Notably, PFT-α suppresses miR-29a-3p levels in CFs under both normal and Ang II-treated conditions. Furthermore, ChIP analysis confirmed that p53 is bound to the promoter region of miR-29a-3p, and directly regulates its expression. Overall, our study demonstrates that LE upregulates p53 and miR-29a-3p expression, and subsequently inhibits CF overactivation, suggesting that the p53/miR-29a-3p axis may play a crucial role in mediating the antifibrotic effect of LE against MF.


Subject(s)
MicroRNAs , Rats , Animals , Angiotensin II/pharmacology , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism , Fibrosis , Collagen Type I/metabolism , Fibroblasts/metabolism
6.
BMC Med ; 21(1): 150, 2023 04 17.
Article in English | MEDLINE | ID: mdl-37069659

ABSTRACT

BACKGROUND: Liver plays an important role in maintaining glucose homeostasis. We aimed to examine the associations of liver enzymes and hepatic steatosis index (HSI, a reliable biomarker for non-alcoholic fatty liver disease) in early pregnancy with subsequent GDM risk, as well as the potential mediation effects of lipid metabolites on the association between HSI and GDM. METHODS: In a birth cohort, liver enzymes were measured in early pregnancy (6-15 gestational weeks, mean 10) among 6,860 Chinese women. Multivariable logistic regression was performed to examine the association between liver biomarkers and risk of GDM. Pearson partial correlation and least absolute shrinkage and selection operator (LASSO) regression were conducted to identify lipid metabolites that were significantly associated with HSI in a subset of 948 women. Mediation analyses were performed to estimate the mediating roles of lipid metabolites on the association of HSI with GDM. RESULTS: Liver enzymes and HSI were associated with higher risks of GDM after adjustment for potential confounders, with ORs ranging from 1.42 to 2.24 for extreme-quartile comparisons (false discovery rate-adjusted P-trend ≤0.005). On the natural log scale, each SD increment of alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, alkaline phosphatase, and HSI was associated with a 1.15-fold (95% CI: 1.05, 1.26), 1.10-fold (1.01, 1.20), 1.21-fold (1.10, 1.32), 1.15-fold (1.04, 1.27), and 1.33-fold (1.18, 1.51) increased risk of GDM, respectively. Pearson partial correlation and LASSO regression identified 15 specific lipid metabolites in relation to HSI. Up to 52.6% of the association between HSI and GDM risk was attributed to the indirect effect of the HSI-related lipid score composed of lipid metabolites predominantly from phospholipids (e.g., lysophosphatidylcholine and ceramides) and triacylglycerol. CONCLUSIONS: Elevated liver enzymes and HSI in early pregnancy, even within a normal range, were associated with higher risks of GDM among Chinese pregnant women. The association of HSI with GDM was largely mediated by altered lipid metabolism.


Subject(s)
Diabetes, Gestational , Pregnancy , Female , Humans , Diabetes, Gestational/epidemiology , Diabetes, Gestational/etiology , Prospective Studies , Pregnant Women , Risk Factors , East Asian People , Liver , Biomarkers , Lipids
7.
Pharmacol Res ; 197: 106969, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37866704

ABSTRACT

Globally, HIV infection causes significant morbidity and mortality, and is a major public health problem. Despite the fact that widespread use of antiretroviral therapy (ART) has substantially altered the natural history of HIV infection from originally being a universally lethal disease to now being a chronic medical condition for those taking appropriate treatment, approximately 10-40% of people living with HIV (PLWH) who take effective ART and maintain long-term viral suppression fail to achieve normalization of CD4 + T-cell counts. This phenomenon is referred to as incomplete immune reconstitution or immunological non-response. Although the precise mechanisms underlying this outcome have not been elucidated, recent evidence indicates that excessive pyroptosis may play a crucial role in the development of incomplete immune reconstitution. Pyroptosis is characterized by the formation of pores in the cell membrane, cell rupture, and secretion of intracellular contents and pro-inflammatory cytokines, including IL-1ß and IL-18. This excessive inflammation-induced programmed cell death leads to a massive loss of CD4 + T-cells, and inflammatory consequences that may promote and sustain incomplete immune reconstitution. Herein, we review the possible pathways activated in HIV infection by inflammasomes that act as switches of pyroptosis, and the role of pyroptosis in HIV, as well as the relevance of CD4 + T-cells in incomplete immune reconstitution. We also highlight the possible mechanisms of pyroptosis involved in incomplete immune reconstitution, thus paving the way for the development of potential targets for the treatment of incomplete immune reconstitution.


Subject(s)
HIV Infections , Immune Reconstitution , Humans , Pyroptosis , HIV Infections/drug therapy , Apoptosis , CD4-Positive T-Lymphocytes
8.
BJOG ; 130(13): 1611-1619, 2023 12.
Article in English | MEDLINE | ID: mdl-37212437

ABSTRACT

OBJECTIVE: To examine the association of a combined healthy lifestyle in early pregnancy with gestational diabetes mellitus (GDM) risk. DESIGN, SETTING AND POPULATION: A Chinese prospective cohort study with 6980 pregnant women. METHODS: Individual modifiable lifestyle factors were assessed in early pregnancy and a combined lifestyle score was derived from the sum of the lifestyle factors, with a higher score indicating a healthier lifestyle. The association of a combined healthy lifestyle with GDM risk was examined. MAIN OUTCOME MEASURES: Gestational diabetes mellitus was diagnosed in middle pregnancy according to the International Association of Diabetes and Pregnancy Study Group criteria or diagnoses in medical records. RESULTS: Overall, 501 (7.2%) pregnant women were diagnosed with GDM. Being physically active (total energy expenditure in upper three quintiles, i.e. ≥100.1 metabolic equivalent of task [MET]-hours/week; odds ratio [OR] 0.76, 95% confidence interval [CI] 0.63-0.92), healthy diet (total intake of vegetables and fruits ≥5 times/day; OR 0.74, 95% CI 0.59-0.94), sufficient sleep (night-time sleep duration ≥7 hours/night; OR 0.66, 95% CI 0.48-0.90) and healthy weight (early-pregnancy BMI <24.0 kg/m2 ; OR 0.57, 95% CI 0.46-0.71) were associated with lower GDM risk. The GDM risk decreased linearly across the combined lifestyle score (Ptrend <0.001): women with 2, 3 and 4 lifestyle factors compared with those with 0-1 factor had 38% (OR 0.62, 95% CI 0.46-0.84), 57% (OR 0.43, 95% CI 0.31-0.58) and 66% (OR 0.34, 95% CI 0.22-0.52) lower risks of GDM, respectively. CONCLUSION: A healthy lifestyle in early pregnancy was associated with a substantially lower GDM risk.


Subject(s)
Diabetes, Gestational , Pregnancy , Female , Humans , Diabetes, Gestational/epidemiology , Diabetes, Gestational/etiology , Prospective Studies , Healthy Lifestyle , Life Style , Risk Factors
9.
BMC Public Health ; 23(1): 2530, 2023 12 18.
Article in English | MEDLINE | ID: mdl-38110936

ABSTRACT

BACKGROUND: The increased number of older persons in China, and the prevalence of most chronic diseases raised with age significantly increased the total disease burden. When a person ages, psychological distress happens when they are faced with stressors that they cannot cope with. Psychological distress refers to non-specific symptoms of depression, anxiety, and stress. Health literacy influences several health outcomes, such as emotional functioning among the population. The primary purpose of this study is to examine the mediator role of health literacy between the presence of chronic disease and psychological distress among older persons living in Xi'an city. Thus, this study used the Cognitive Behavior Theory (CBT) as a combination of the basic behavioral and cognitive psychology principles to explain the cognitive processes associated with psychological distress. METHODS: This study employs a quantitative research design using a cross-sectional survey of 300 older persons over 60 years living in the six urban districts of Xi'an city. Data were collected using the Health Literacy Questionnaire (HLQ) and the Depression Anxiety Stress Scale (DASS-21). This study employed descriptive statistics and inferential methods to analyze the data. The inferential methods applied structural equation modeling (SEM) to test the hypothesis of the mediator role of health literacy between the presence of chronic disease and psychological distress. RESULTS: In this study, chronic disease had an effect on health literacy among older persons living in Xi'an city (ß=-0.047, p < 0.01); chronic disease impact on psychological distress among older persons living in Xi'an city (ß = 0.047, p < 0.01); health literacy was identified effect on psychological distress among older persons in Xi'an city (ß=-0.738, p < 0.001); health literacy as a partial mediator between chronic disease and psychological distress (ß = 0.07, p < 0.01). CONCLUSION: Psychological distress among older persons is affected by chronic disease and health literacy. Health literacy had a partial mediating effect on the presence of chronic disease and psychological distress. Improved health literacy measures should be considered when treating older persons with psychological distress.


Subject(s)
Health Literacy , Psychological Distress , Humans , Aged , Aged, 80 and over , Cross-Sectional Studies , China/epidemiology , Chronic Disease
10.
Biomed Chromatogr ; 37(4): e5573, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36529812

ABSTRACT

Moscatilin, a bibenzyl derivative from the stem of Dendrobium loddigesii, has been shown to have anticancer activity. The aim of this study was to identify and characterize the possible in vitro metabolites of moscatilin generated from hepatocytes. The metabolites generated in the hepatocytes of mouse, rat, dog, monkey and human were identified and characterized employing ultra-high-performance liquid chromatography coupled with quadrupole Orbitrap tandem mass spectrometry (LC-Orbitrap-MS/MS) based on diagnostic fragment ions and accurate mass measurements. A total of 18 metabolites were identified, among which seven were phase I and 11 were phase II metabolites. The plausible structures of the metabolites and the probable biotransformation pathways were proposed based on the diagnostic fragment ions, chemical formula and mass fragmentation pattern, as well as the accurate masses. The majority of phase I metabolites were generated by demethylation and hydroxylation, while phase II metabolites were mainly generated by glucuronidation, glutathione conjugation and sulfation. Our study first expounded the metabolites of moscatilin in mouse, rat, dog, monkey and human hepatocytes and provided a foundation for a further pharmacokinetic and toxicity study. More importantly, LC-Orbitrap-MS/MS combined with diagnostic fragment ions and accurate mass measurements has been proved to be an effective method for the rapid identification of bibenzyl derivatives and their metabolites.


Subject(s)
Bibenzyls , Tandem Mass Spectrometry , Rats , Humans , Dogs , Mice , Animals , Tandem Mass Spectrometry/methods , Haplorhini , Hepatocytes/metabolism
11.
BMC Biol ; 20(1): 188, 2022 08 24.
Article in English | MEDLINE | ID: mdl-36002819

ABSTRACT

BACKGROUND: The blue-crowned laughingthrush (Garrulax courtoisi) is a critically endangered songbird endemic to Wuyuan, China, with population of ~323 individuals. It has attracted widespread attention, but the lack of a published genome has limited research and species protection. RESULTS: We report two laughingthrush genome assemblies and reveal the taxonomic status of laughingthrush species among 25 common avian species according to the comparative genomic analysis. The blue-crowned laughingthrush, black-throated laughingthrush, masked laughingthrush, white-browed laughingthrush, and rusty laughingthrush showed a close genetic relationship, and they diverged from a common ancestor between ~2.81 and 12.31 million years ago estimated by the population structure and divergence analysis using 66 whole-genome sequencing birds from eight laughingthrush species and one out group (Cyanopica cyanus). Population inference revealed that the laughingthrush species experienced a rapid population decline during the last ice age and a serious bottleneck caused by a cold wave during the Chinese Song Dynasty (960-1279 AD). The blue-crowned laughingthrush is still in a bottleneck, which may be the result of a cold wave together with human exploitation. Interestingly, the existing blue-crowned laughingthrush exhibits extremely rich genetic diversity compared to other laughingthrushes. These genetic characteristics and demographic inference patterns suggest a genetic heritage of population abundance in the blue-crowned laughingthrush. The results also suggest that fewer deleterious mutations in the blue-crowned laughingthrush genomes have allowed them to thrive even with a small population size. We believe that cooperative breeding behavior and a long reproduction period may enable the blue-crowned laughingthrush to maintain genetic diversity and avoid inbreeding depression. We identified 43 short tandem repeats that can be used as markers to identify the sex of the blue-crowned laughingthrush and aid in its genetic conservation. CONCLUSIONS: This study supplies the missing reference genome of laughingthrush, provides insight into the genetic variability, evolutionary potential, and molecular ecology of laughingthrush and provides a genomic resource for future research and conservation.


Subject(s)
Passeriformes , Animals , Biological Evolution , Breeding , Genetic Variation , Genome , Genomics , Humans , Passeriformes/genetics
12.
Zhongguo Zhong Yao Za Zhi ; 48(23): 6457-6474, 2023 Dec.
Article in Zh | MEDLINE | ID: mdl-38212003

ABSTRACT

The Baimai Ointment with the effect of relaxing sinew and activating collaterals demonstrates a definite effect on Baimai disease with pain, spasm, stiffness and other symptoms, while the pharmacodynamic characteristics and mechanism of this agent remain unclear. In this study, a rat model of chronic compression of L4 dorsal root ganglion(CCD) was established by lumbar disc herniation, and the efficacy and mechanism of Baimai Ointment in the treatment of CCD were preliminarily explored by behavioral tests, side effect evaluation, network analysis, antagonist and molecular biology verification. The pharmacodynamic experiment indicated that Baimai Ointment significantly improved the pain thresholds(mechanical pain, thermal pain, and cold pain) and gait behavior of CCD model rats without causing tolerance or obvious toxic and side effects. Baimai Ointment inhibited the second-phase nociceptive response of mice in the formalin test, increased the hot plate threshold of normal mice, and down-regulated the expression of inflammatory cytokines in the spinal cord. Network analysis showed that Baimai Ointment had synergistic effect in the treatment of CCD and was related to descending inhibition/facilitation system and neuroinflammation. Furthermore, behavioral tests, Western blot, and immunofluorescence assay revealed that the pain-relieving effect of Baimai Ointment on CCD may be related to the regulation of the interaction between neuroactive ligand and receptors(neuroligands) such as CHRNA7, ADRA2A, and ADRB2, and the down-regulation of the expression of NOS2/pERK/PI3K, the core regulatory element of HIF-1 signaling pathway in spinal microglia. The findings preliminarily reveal the mechanism of relaxing sinew and activating collaterals of Baimai Ointment in the treatment of Baimai disease, providing a reference for the rational drug use and further research of this agent.


Subject(s)
Chronic Pain , Drugs, Chinese Herbal , Rats , Mice , Animals , Chronic Pain/complications , Chronic Pain/metabolism , Rats, Sprague-Dawley , Ganglia, Spinal/metabolism , Ligands , Signal Transduction , Hyperalgesia/drug therapy , Hyperalgesia/etiology , Hyperalgesia/metabolism
13.
Angew Chem Int Ed Engl ; 62(15): e202300691, 2023 Apr 03.
Article in English | MEDLINE | ID: mdl-36786065

ABSTRACT

Free carbene readily causes multiple side reactions due to its high energy, thus its asymmetric transformation is very difficult. We present here our findings of high-pKa Brønsted acid catalysts that enable free carbene insertion into N-H bonds of amines to prepare chiral α-amino acid derivatives with high enantioselectivity. Under irradiation with visible light, diazo compounds produce high-energy free carbenes that are captured by amines to form free ylide intermediates, and then the newly designed high-pKa Brønsted acids, chiral spiro phosphamides, promote the proton transfer of ylides to afford the products. Computational and kinetic studies uncover the principle for the rational design of proton-transfer catalysts and explain how the catalysts accelerate this transformation and provide stereocontrol.

14.
Angew Chem Int Ed Engl ; 62(25): e202300993, 2023 Jun 19.
Article in English | MEDLINE | ID: mdl-37074229

ABSTRACT

Photoinduced metal-organic framework (MOF) enabled heterogeneous thiol catalysis has been achieved for the first time. MOF Zr-TPDCS-1, consisting of Zr6 -clusters and TPDCS linkers (TPDCS=3,3'',5,5''-tetramercapto[1,1':4',1''-terphenyl]-4,4''-dicarboxylate), effectively catalyzed the borylation, silylation, phosphorylation, and thiolation of organic molecules. Upon irradiation, the fast electron transfer from TPDCS to Zr6 -cluster is believed to facilitate the formation of the thiyl radical, a hydrogen atom transfer catalyst, which competently abstracts the hydrogen from borane, silane, phosphine, or thiol for generating the corresponding element radical to engender the chemical transformations. The elaborate control experiments evidenced the generation of thiyl radicals in MOF and illustrated a radical reaction pathway. The gram-scale reaction worked well, and the product was conveniently separated via centrifugation and vacuum with a turnover number (TON) of ≈3880, highlighting the practical application potential of heterogeneous thiyl-radical catalysis.


Subject(s)
Metal-Organic Frameworks , Sulfhydryl Compounds , Sulfhydryl Compounds/chemistry , Catalysis , Hydrogen/chemistry
15.
Biochem Biophys Res Commun ; 615: 163-171, 2022 07 30.
Article in English | MEDLINE | ID: mdl-35665610

ABSTRACT

BACKGROUNDS: Although several studies on mutant p53 reported cancer-promoting activities via "gain-of-function", the mechanism underlying these differences in function between p53 R175H, R175P, and p53 wild-type (WT) remains unclear. METHODS: Linking miniTurbo with p53 WT, R175H, and R175P, the expression of fusion and biotinylated proteins were assessed by Western blotting. The function and subcellular localization of fusion proteins were detected by apoptosis assay and immunofluorescence, respectively. Biotinylated proteins were analyzed by liquid chromatography-tandem mass spectrometry, followed by bioinformatics analysis. Small-scale pull-downs and Co-Immunoprecipitation were performed to validate the interaction between mutant or p53 WT and biotinylated proteins. RESULTS: The fusion protein's cellular localization and function were consistent with those of previous studies on the corresponding p53. Comparative profiles of R175H versus WT showed that most of the interacting proteins belonged to the intracellular organelle lumen, and the pathways involved were metabolism and genetic information processing. Comparative profiles of R175P versus WT suggested that the majority of the interacting proteins belonged to the intracellular organelle lumen and the extracellular membrane-bounded organelle, and the pathways involved were metabolism and genetic information processing pathways. The comparison between R175H and R175P revealed that most interacting proteins belonged to the organelle lumen, and pathways involved were genetic information processing pathways. Finally, the mutation of p53 significantly altered the interaction with the target proteins were confirmed. CONCLUSION: We verified the reliability of the miniTurbo system and obtained candidate targets of mutant p53, which provided new thoughts on the mechanism of mutant p53 gain-of-function and new potential targets for cancer therapy.


Subject(s)
Tumor Suppressor Protein p53 , Cell Line, Tumor , Mutant Proteins/metabolism , Mutation , Reproducibility of Results , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism
16.
J Clin Densitom ; 25(4): 544-552, 2022.
Article in English | MEDLINE | ID: mdl-35963761

ABSTRACT

To investigate the association between blood routine (BRT) parameters and bone loss as well as the possible mechanism of this association with bone loss in the middle- aged and elderly patients. A total of nine hundred and ninety-eight subjects (the total) aged≥40 years in General Hospital of Southern Theater Command of People's Liberation Army from March 2015 to January 2018 were enrolled in a cross-sectional studyPatients were divided into two groups as "at least osteopenia group" (including osteopenia, osteoporosis, and severe osteoporosis) and "normal group" according to the diagnosis standard of OP. The above indicators were analyzed and compared between the two groups. Binary multivariate logistic regression analysis was carried out to explore the association between BRT parameters and risk of bone loss in the subjects Mediation Effect was conducted to test endocrine variables as mediators in the correlation of BRT parameters with the bone loss for the possible mechanisms. There were 669 cases in the at least osteopenia group and 329 in the normal group. RBC, Hb, HCT and MCHC were all positively correlated with BMD of lumbar spine(L1-4), left femoral neck and left femur, along with lymph positively correlated with BMD of left femoral neck and left femur, respectively. Eosinophils(Eo) was positively correlated with BMD of L1-L4 and RDW-SD together with RDW-CV were both negatively correlated with BMD of left femoral neck and left femur. By binary multivariate logistic regression, only Hb was associated with bone loss and the OR value was 0.478 as protective factor for BMD. Estradiol (E2) and testosterone (T) had partial mediating effect on the association of BRT parameters with the risk of bone loss. The mediating effect of E2 on the relationship between WBC and bone loss accounted for 46.35% of the total effect, and that of T on the relationship between RBC, Hb, HCT, MCHC and bone loss accounted for 27%, 18.3%, 31.1% and 26.8%, respectively. Bone loss in the middle-aged and elderly population is accompanied with the change of BRT parameters and the erythrocyte indices tend to be more obvious especially the Hb, which indicates anemia had a potential connection with bone loss. Sex hormone, especially T, is an important mediating variable in the association between blood routine parameters and bone loss.


Subject(s)
Bone Diseases, Metabolic , Osteoporosis , Middle Aged , Aged , Humans , Bone Density , Cross-Sectional Studies , Osteoporosis/epidemiology , Bone Diseases, Metabolic/diagnostic imaging , Bone Diseases, Metabolic/epidemiology , Femur Neck/diagnostic imaging , Lumbar Vertebrae , Estradiol
17.
Anim Genet ; 53(5): 599-612, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35735069

ABSTRACT

With the improvement in sequencing technology and the decrease in sequencing cost, increasing amounts of genomic data for pigs have been uploaded to public databases. However, no researchers have to date integrated all currently available data to uncover the global genetic status of pigs. Meanwhile, little is known about the introgression from European to Chinese pigs and its underlying influences. Therefore, we integrated the effective genotype data of 3907 pigs from 193 populations worldwide using population genetic analysis, gene flow analysis and a sharing-IBD study. These findings illustrate not only the population structure of 59 Chinese native breeds and others but also the amounts of gene flow and introgression that have occurred between Western and Chinese pigs. In addition, we demonstrate the presence of introgressed European haplotypes in Chinese indigenous breeds and identify relevant introgressed regions that contain genes associated with growth and feed efficiency. Moreover, we compare the introgression patterns of Western and Chinese pigs and further discuss possible explanations for why the level of introgression differs between Chinese pig breeds and Western modern breeds. Collectively, this study provides a fine global population structure analysis of pigs and presents evidence of European pigs being interbred with local breeds in China.


Subject(s)
Polymorphism, Single Nucleotide , Sus scrofa , Animals , China , Genetic Variation , Genetics, Population , Haplotypes , Sus scrofa/genetics , Swine/genetics
18.
J Asian Nat Prod Res ; 24(8): 738-745, 2022 Aug.
Article in English | MEDLINE | ID: mdl-34581235

ABSTRACT

Two new triucallane triterpenoids, polystanin F (1) and polystanin G (2), along with eight known compounds (3-10) were isolated from the fruits of Aphanamixis polystachya. Their structures were established on the basis of extensive spectroscopic analysis. Moreover, eight compounds were evaluated for their in vitro cytotoxicity against three cancer cell lines (liver cancer RT112, colon cancer HCT-116 and breast cancer M231) using the MTT method. Compound 7 showed significant cytotoxic activity against HCT-116 with IC50 1.27 µM.


Subject(s)
Limonins , Meliaceae , Triterpenes , Fruit/chemistry , Limonins/chemistry , Meliaceae/chemistry , Molecular Structure , Triterpenes/analysis , Triterpenes/pharmacology
19.
Clin Infect Dis ; 73(1): 144-147, 2021 07 01.
Article in English | MEDLINE | ID: mdl-32756974

ABSTRACT

Elite controllers (ECs) are people living with human immunodeficiency virus (HIV) who spontaneously control viral replication without antiretroviral therapy. We observed that elevated anti-cytomegalovirus (CMV) immunoglobulin G (IgG) levels correlated with annual CD4 T-cell count decay in ECs independently of age, sex, and human leukocyte antigen (HLA) type. Elevated anti-CMV titers may favor disease progression in ECs.


Subject(s)
HIV Infections , HIV-1 , CD4 Lymphocyte Count , CD4-Positive T-Lymphocytes , Cell Count , Cytomegalovirus , HIV Infections/drug therapy , Humans , Immunoglobulin G , Viral Load
20.
J Am Chem Soc ; 143(17): 6401-6406, 2021 05 05.
Article in English | MEDLINE | ID: mdl-33904721

ABSTRACT

Chiral propargylsilanes and chiral allenylsilanes have emerged as versatile building blocks for organic synthesis. However, efficient methods for preparing these organosilicon compounds are lacking. We herein report a highly enantioselective method for synthesis of chiral propargylsilanes and chiral allenylsilanes from readily available alkynyl sulfonylhydrazones. Specifically, chiral spiro phosphate dirhodium complexes were used to catalyze asymmetric insertion of alkynyl carbenes into the Si-H bonds of silanes to afford a variety of chiral propargylsilanes with excellent enantioselectivity. Subsequently, a platinum catalyst was used for stereospecific isomerization of the chiral propargylsilanes to the corresponding chiral allenylsilanes.

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