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1.
Nature ; 629(8014): 1174-1181, 2024 May.
Article in English | MEDLINE | ID: mdl-38720073

ABSTRACT

Phosphorylation of proteins on tyrosine (Tyr) residues evolved in metazoan organisms as a mechanism of coordinating tissue growth1. Multicellular eukaryotes typically have more than 50 distinct protein Tyr kinases that catalyse the phosphorylation of thousands of Tyr residues throughout the proteome1-3. How a given Tyr kinase can phosphorylate a specific subset of proteins at unique Tyr sites is only partially understood4-7. Here we used combinatorial peptide arrays to profile the substrate sequence specificity of all human Tyr kinases. Globally, the Tyr kinases demonstrate considerable diversity in optimal patterns of residues surrounding the site of phosphorylation, revealing the functional organization of the human Tyr kinome by substrate motif preference. Using this information, Tyr kinases that are most compatible with phosphorylating any Tyr site can be identified. Analysis of mass spectrometry phosphoproteomic datasets using this compendium of kinase specificities accurately identifies specific Tyr kinases that are dysregulated in cells after stimulation with growth factors, treatment with anti-cancer drugs or expression of oncogenic variants. Furthermore, the topology of known Tyr signalling networks naturally emerged from a comparison of the sequence specificities of the Tyr kinases and the SH2 phosphotyrosine (pTyr)-binding domains. Finally we show that the intrinsic substrate specificity of Tyr kinases has remained fundamentally unchanged from worms to humans, suggesting that the fidelity between Tyr kinases and their protein substrate sequences has been maintained across hundreds of millions of years of evolution.


Subject(s)
Phosphotyrosine , Protein-Tyrosine Kinases , Substrate Specificity , Tyrosine , Animals , Humans , Amino Acid Motifs , Evolution, Molecular , Mass Spectrometry , Phosphoproteins/chemistry , Phosphoproteins/metabolism , Phosphorylation , Phosphotyrosine/metabolism , Protein-Tyrosine Kinases/drug effects , Protein-Tyrosine Kinases/metabolism , Proteome/chemistry , Proteome/metabolism , Proteomics , Signal Transduction , src Homology Domains , Tyrosine/metabolism , Tyrosine/chemistry
2.
Plant Cell ; 2024 May 09.
Article in English | MEDLINE | ID: mdl-38723161

ABSTRACT

The conserved microRNA (miRNA) miR408 enhances photosynthesis and compromises stress tolerance in multiple plants, but the cellular mechanism underlying its function remains largely unclear. Here, we show that in Arabidopsis (Arabidopsis thaliana), the transcript encoding the blue copper protein PLANTACYANIN (PCY) is the primary target for miR408 in vegetative tissues. PCY is preferentially expressed in the guard cells, and PCY is associated with the endomembrane surrounding individual chloroplasts. We found that the MIR408 promoter is suppressed by multiple abscisic acid (ABA)-responsive transcription factors, thus allowing PCY to accumulate under stress conditions. Genetic analysis revealed that PCY elevates reactive oxygen species (ROS) levels in the guard cells, promotes stomatal closure, reduces photosynthetic gas exchange, and enhances drought resistance. Moreover, the miR408-PCY module is sufficient to rescue the growth and drought tolerance phenotypes caused by gain- and loss-of-function of MYB44, an established positive regulator of ABA responses, indicating that the miR408-PCY module relays ABA signaling for regulating ROS homeostasis and drought resistance. These results demonstrate that miR408 regulates stomatal movement to balance growth and drought resistance, providing a mechanistic understanding of why miR408 is selected during land plant evolution and insights into the long-pursued quest of breeding drought-tolerant and high-yielding crops.

3.
Proc Natl Acad Sci U S A ; 121(11): e2316544121, 2024 Mar 12.
Article in English | MEDLINE | ID: mdl-38442155

ABSTRACT

Muscle regeneration is a complex process relying on precise teamwork between multiple cell types, including muscle stem cells (MuSCs) and fibroadipogenic progenitors (FAPs). FAPs are also the main source of intramuscular adipose tissue (IMAT). Muscles without FAPs exhibit decreased IMAT infiltration but also deficient muscle regeneration, indicating the importance of FAPs in the repair process. Here, we demonstrate the presence of bidirectional crosstalk between FAPs and MuSCs via their secretion of extracellular vesicles (EVs) containing distinct clusters of miRNAs that is crucial for normal muscle regeneration. Thus, after acute muscle injury, there is activation of FAPs leading to a transient rise in IMAT. These FAPs also release EVs enriched with a selected group of miRNAs, a number of which come from an imprinted region on chromosome 12. The most abundant of these is miR-127-3p, which targets the sphingosine-1-phosphate receptor S1pr3 and activates myogenesis. Indeed, intramuscular injection of EVs from immortalized FAPs speeds regeneration of injured muscle. In late stages of muscle repair, in a feedback loop, MuSCs and their derived myoblasts/myotubes secrete EVs enriched in miR-206-3p and miR-27a/b-3p. The miRNAs repress FAP adipogenesis, allowing full muscle regeneration. Together, the reciprocal communication between FAPs and muscle cells via miRNAs in their secreted EVs plays a critical role in limiting IMAT infiltration while stimulating muscle regeneration, hence providing an important mechanism for skeletal muscle repair and homeostasis.


Subject(s)
Extracellular Vesicles , MicroRNAs , Satellite Cells, Skeletal Muscle , Muscle Fibers, Skeletal , Communication , MicroRNAs/genetics , Regeneration/genetics
4.
Proc Natl Acad Sci U S A ; 121(21): e2401748121, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38739789

ABSTRACT

Potyviridae, the largest family of plant RNA viruses, includes many important pathogens that significantly reduce the yields of many crops worldwide. In this study, we report that the 6-kilodalton peptide 1 (6K1), one of the least characterized potyviral proteins, is an endoplasmic reticulum-localized protein. AI-assisted structure modeling and biochemical assays suggest that 6K1 forms pentamers with a central hydrophobic tunnel, can increase the cell membrane permeability of Escherichia coli and Nicotiana benthamiana, and can conduct potassium in Saccharomyces cerevisiae. An infectivity assay showed that viral proliferation is inhibited by mutations that affect 6K1 multimerization. Moreover, the 6K1 or its homologous 7K proteins from other viruses of the Potyviridae family also have the ability to increase cell membrane permeability and transmembrane potassium conductance. Taken together, these data reveal that 6K1 and its homologous 7K proteins function as viroporins in viral infected cells.


Subject(s)
Nicotiana , Nicotiana/virology , Nicotiana/metabolism , Potyviridae/genetics , Potyviridae/metabolism , Viral Proteins/metabolism , Viral Proteins/genetics , Cell Membrane Permeability , Endoplasmic Reticulum/metabolism , Endoplasmic Reticulum/virology , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Viroporin Proteins/metabolism , Viroporin Proteins/genetics , Escherichia coli/genetics , Escherichia coli/metabolism , Plant Viruses/genetics , Plant Viruses/physiology , Plant Diseases/virology , Potassium/metabolism
5.
Brief Bioinform ; 25(4)2024 May 23.
Article in English | MEDLINE | ID: mdl-38828640

ABSTRACT

Cell hashing, a nucleotide barcode-based method that allows users to pool multiple samples and demultiplex in downstream analysis, has gained widespread popularity in single-cell sequencing due to its compatibility, simplicity, and cost-effectiveness. Despite these advantages, the performance of this method remains unsatisfactory under certain circumstances, especially in experiments that have imbalanced sample sizes or use many hashtag antibodies. Here, we introduce a hybrid demultiplexing strategy that increases accuracy and cell recovery in multi-sample single-cell experiments. This approach correlates the results of cell hashing and genetic variant clustering, enabling precise and efficient cell identity determination without additional experimental costs or efforts. In addition, we developed HTOreader, a demultiplexing tool for cell hashing that improves the accuracy of cut-off calling by avoiding the dominance of negative signals in experiments with many hashtags or imbalanced sample sizes. When compared to existing methods using real-world datasets, this hybrid approach and HTOreader consistently generate reliable results with increased accuracy and cell recovery.


Subject(s)
Single-Cell Analysis , Single-Cell Analysis/methods , Humans , Algorithms , Software , High-Throughput Nucleotide Sequencing/methods , Computational Biology/methods
6.
J Neurosci ; 44(20)2024 May 15.
Article in English | MEDLINE | ID: mdl-38565291

ABSTRACT

Microglia undergo two-stage activation in neurodegenerative diseases, known as disease-associated microglia (DAM). TREM2 mediates the DAM2 stage transition, but what regulates the first DAM1 stage transition is unknown. We report that glucose dyshomeostasis inhibits DAM1 activation and PKM2 plays a role. As in tumors, PKM2 was aberrantly elevated in both male and female human AD brains, but unlike in tumors, it is expressed as active tetramers, as well as among TREM2+ microglia surrounding plaques in 5XFAD male and female mice. snRNAseq analyses of microglia without Pkm2 in 5XFAD mice revealed significant increases in DAM1 markers in a distinct metabolic cluster, which is enriched in genes for glucose metabolism, DAM1, and AD risk. 5XFAD mice incidentally exhibited a significant reduction in amyloid pathology without microglial Pkm2 Surprisingly, microglia in 5XFAD without Pkm2 exhibited increases in glycolysis and spare respiratory capacity, which correlated with restoration of mitochondrial cristae alterations. In addition, in situ spatial metabolomics of plaque-bearing microglia revealed an increase in respiratory activity. These results together suggest that it is not only glycolytic but also respiratory inputs that are critical to the development of DAM signatures in 5XFAD mice.


Subject(s)
Glucose , Homeostasis , Mice, Transgenic , Microglia , Animals , Microglia/metabolism , Microglia/pathology , Mice , Homeostasis/physiology , Glucose/metabolism , Male , Female , Humans , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Alzheimer Disease/genetics , Membrane Glycoproteins/metabolism , Membrane Glycoproteins/genetics , Receptors, Immunologic/metabolism , Receptors, Immunologic/genetics , Glycolysis/physiology , Thyroid Hormone-Binding Proteins
7.
FASEB J ; 38(1): e23361, 2024 01.
Article in English | MEDLINE | ID: mdl-38085152

ABSTRACT

Oocyte meiotic prophase I (MI) is an important event in female reproduction. Breast cancer amplified sequence 2 (BCAS2) is a component of the spliceosome. Previous reports have shown that BCAS2 is critical in male germ cell meiosis, oocyte development, and early embryo genome integrity. However, the role of BCAS2 in oocyte meiosis has not been reported. We used Stra8-GFPCre mice to knock out Bcas2 in oocytes during the pachytene phase. The results of fertility tests showed that Bcas2 conditional knockout (cKO) in oocytes results in infertility in female mice. Morphological analysis showed that the number of primordial follicles in the ovaries of 2-month-old (M) mice was significantly reduced and that follicle development was blocked. Further analysis showed that the number of primordial follicles decreased and that follicle development was slowed in 7-day postpartum (dpp) ovaries. Moreover, primordial follicles undergo apoptosis, and DNA damage cannot be repaired in primary follicle oocytes. Meiosis was abnormal; some oocytes could not reach the diplotene stage, and more oocytes could not develop to the dictyotene stage. Alternative splicing (AS) analysis revealed abnormal AS of deleted in azoospermia like (Dazl) and diaphanous related formin 2 (Diaph2) oogenesis-related genes in cKO mouse ovaries, and the process of AS was involved by CDC5L and PRP19.


Subject(s)
Meiosis , Meiotic Prophase I , Male , Female , Mice , Animals , Meiosis/genetics , Alternative Splicing , RNA, Messenger/metabolism , Oocytes/metabolism , Neoplasm Proteins/metabolism
8.
Mol Ther ; 32(7): 2176-2189, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38734896

ABSTRACT

The disassembly of the neuromuscular junction (NMJ) is an early event in amyotrophic lateral sclerosis (ALS), ultimately leading to motor dysfunction and lethal respiratory paralysis. The hexanucleotide GGGGCC repeat expansion in the C9orf72 gene is the most common genetic mutation, and the dipeptide repeat (DPR) proteins have been shown to cause neurodegeneration. While no drugs can treat ALS patients efficiently, new treatment strategies are urgently needed. Here, we report that a MuSK agonist antibody alleviates poly-PR-induced NMJ deficits in C9orf72-ALS mice. The HB9-PRF/F mice, which express poly-PR proteins in motor neurons, exhibited impaired motor behavior and NMJ deficits. Mechanistically, poly-PR proteins interacted with Agrin to disrupt the interaction between Agrin and Lrp4, leading to attenuated activation of MuSK. Treatment with a MuSK agonist antibody rescued NMJ deficits, and extended the lifespan of C9orf72-ALS mice. Moreover, impaired NMJ transmission was observed in C9orf72-ALS patients. These findings identify the mechanism by which poly-PR proteins attenuate MuSK activation and NMJ transmission, highlighting the potential of promoting MuSK activation with an agonist antibody as a therapeutic strategy to protect NMJ function and prolong the lifespan of ALS patients.


Subject(s)
Amyotrophic Lateral Sclerosis , C9orf72 Protein , Disease Models, Animal , Neuromuscular Junction , Receptor Protein-Tyrosine Kinases , Animals , Neuromuscular Junction/metabolism , Neuromuscular Junction/drug effects , Mice , Amyotrophic Lateral Sclerosis/genetics , Amyotrophic Lateral Sclerosis/metabolism , Amyotrophic Lateral Sclerosis/drug therapy , C9orf72 Protein/genetics , C9orf72 Protein/metabolism , Humans , Receptor Protein-Tyrosine Kinases/metabolism , Receptor Protein-Tyrosine Kinases/genetics , Longevity/drug effects , Motor Neurons/metabolism , Motor Neurons/drug effects , Agrin/metabolism , Agrin/genetics , Mice, Transgenic , Antibodies/pharmacology , Receptors, Cholinergic/metabolism , Receptors, Cholinergic/genetics , LDL-Receptor Related Proteins/metabolism , LDL-Receptor Related Proteins/genetics
9.
Mol Ther ; 32(8): 2624-2640, 2024 Aug 07.
Article in English | MEDLINE | ID: mdl-38956871

ABSTRACT

Chronic pancreatitis (CP) is marked by progressive fibrosis and the activation of pancreatic stellate cells (PSCs), accompanied by the destruction of pancreatic parenchyma, leading to the loss of acinar cells (ACs). Few research studies have explored the mechanism by which damaged ACs (DACs) contribute to PSCs activation and pancreatic fibrosis. Currently, there are no effective drugs for curing CP or limiting the progression of pancreatic fibrosis. In this research, co-culture with intact acinar cells (IACs) suppressed PSC activation, while co-culture with DACs did the opposite. Krüppel-like factor 4 (KLF4) was significantly upregulated in DACs and was established as the key molecule that switches ACs from PSCs-suppressor to PSCs-activator. We revealed the exosomes of IACs contributed to the anti-activated function of IACs-CS on PSCs. MiRNome profiling showed that let-7 family is significantly enriched in IAC-derived exosomes (>30% miRNome), which partially mediates IACs' suppressive impacts on PSCs. Furthermore, it has been observed that the enrichment of let-7 in exosomes was influenced by the expression level of KLF4. Mechanistic studies demonstrated that KLF4 in ACs upregulated Lin28A, thereby decreasing let-7 levels in AC-derived exosomes, and thus promoting PSCs activation. We utilized an adeno-associated virus specifically targeting KLF4 in ACs (shKLF4-pAAV) to suppress PSCs activation in CP, resulting in reduced pancreatic fibrosis. IAC-derived exosomes hold potential as potent weapons against PSCs activation via let-7s, while activated KLF4/Lin28A signaling in DACs diminished such functions. ShKLF4-pAAV holds promise as a novel therapeutic approach for CP.


Subject(s)
Acinar Cells , Exosomes , Fibrosis , Kruppel-Like Factor 4 , MicroRNAs , Pancreatic Stellate Cells , Pancreatitis, Chronic , Kruppel-Like Factor 4/metabolism , Animals , Pancreatic Stellate Cells/metabolism , Pancreatic Stellate Cells/pathology , Exosomes/metabolism , Pancreatitis, Chronic/metabolism , Pancreatitis, Chronic/genetics , Pancreatitis, Chronic/pathology , MicroRNAs/genetics , Acinar Cells/metabolism , Acinar Cells/pathology , Dependovirus/genetics , Mice , Humans , Kruppel-Like Transcription Factors/metabolism , Kruppel-Like Transcription Factors/genetics , Disease Models, Animal , Genetic Vectors/genetics , Genetic Vectors/administration & dosage , Male , Coculture Techniques , Pancreas/metabolism , Pancreas/pathology , Genetic Therapy/methods
10.
BMC Biol ; 22(1): 119, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38769511

ABSTRACT

BACKGROUND: Many efforts have been made to improve the precision of Cas9-mediated gene editing through increasing knock-in efficiency and decreasing byproducts, which proved to be challenging. RESULTS: Here, we have developed a human exonuclease 1-based genome-editing tool, referred to as exonuclease editor. When compared to Cas9, the exonuclease editor gave rise to increased HDR efficiency, reduced NHEJ repair frequency, and significantly elevated HDR/indel ratio. Robust gene editing precision of exonuclease editor was even superior to the fusion of Cas9 with E1B or DN1S, two previously reported precision-enhancing domains. Notably, exonuclease editor inhibited NHEJ at double strand breaks locally rather than globally, reducing indel frequency without compromising genome integrity. The replacement of Cas9 with single-strand DNA break-creating Cas9 nickase further increased the HDR/indel ratio by 453-fold than the original Cas9. In addition, exonuclease editor resulted in high microhomology-mediated end joining efficiency, allowing accurate and flexible deletion of targeted sequences with extended lengths with the aid of paired sgRNAs. Exonuclease editor was further used for correction of DMD patient-derived induced pluripotent stem cells, where 30.0% of colonies were repaired by HDR versus 11.1% in the control. CONCLUSIONS: Therefore, the exonuclease editor system provides a versatile and safe genome editing tool with high precision and holds promise for therapeutic gene correction.


Subject(s)
Exodeoxyribonucleases , Gene Editing , Gene Editing/methods , Humans , Exodeoxyribonucleases/genetics , Exodeoxyribonucleases/metabolism , CRISPR-Cas Systems , HEK293 Cells , DNA Repair Enzymes
11.
Nano Lett ; 24(31): 9760-9767, 2024 Aug 07.
Article in English | MEDLINE | ID: mdl-39073854

ABSTRACT

Efficient utilization of solar energy for photocatalytic applications, particularly in the infrared spectrum, is crucial for addressing environmental challenges and energy scarcity. Herein we present a general strategy for constructing efficient infrared-driven photocatalysts in a metal/semiconductor heterojunction with Ohmic contact, where metals with low work function as the infrared-light absorber and semiconductors with electron storage ability can overcome the unfavorable electron flowback. Taking the NixB/MO2 (M = Ce, Ti, Sn, Ge, Zr, etc.) heterojunction as an example, both experimental and theoretical investigations reveal that the formation of an Ohmic contact facilitates the transfer of hot electrons from NixB to MO2, which are stored by the ion redox pairs for the variable valence character of M. As expected, the heterojunction exhibits remarkable photocatalytic activity under infrared light (λ ≥ 800 nm), as evidenced by the efficient photofixation of CO2 to high-value-added cyclic carbonates. This study offers a general platform for designing infrared-light-driven photocatalysts.

12.
Nano Lett ; 24(6): 2094-2101, 2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38315573

ABSTRACT

Prelithiation plays a crucial role in advancing the development of high-energy-density batteries, and ultrathin lithium (UTL) has been proven to be a promising anode prelithiation reagent. However, there remains a need to explore an adjustable, efficient, and cost-effective method for manufacturing UTL. In this study, we introduce a method for producing UTL with adjustable thicknesses ranging from 1.5 to 10 µm through blade coating of molten lithium on poly(vinylidene fluoride)-modified copper current collectors. By employing the transfer-printing method, prelithiated graphite and Si-C composite electrodes are prepared, which exhibit significantly improved initial Coulombic efficiencies of 99.60% and 99.32% in half-cells, respectively. Moreover, the energy densities of Li(NiCoMn)1/3O2 and LiFePO4 full cells assembled with the prelithiated graphite electrodes increase by 13.1% and 23.6%, respectively.

13.
Nano Lett ; 2024 Aug 19.
Article in English | MEDLINE | ID: mdl-39158928

ABSTRACT

Surface ligand chemistry is vital to control the synthesis, diminish surface defects, and improve the electronic coupling of quantum dots (QDs) toward emerging applications in optoelectronic devices. Here, we successfully develop highly homogeneous and dispersed AgBiS2 QDs, focus on the control of interdot spacing, and substitute the long-chain ligands with ammonium iodide in solution. This results in improved electronic coupling of AgBiS2 QDs with excellent surface passivation, which greatly facilitates carrier transport within the QD films. Based on the stable AgBiS2 QD dispersion with the optimal ligand state, a homogeneous and densely packed QD film is prepared by a facile one-step coating process, delivering a champion power conversion efficiency of approximately 8% in the QD solar cells with outstanding shelf life stability. The proposed surface engineering strategy holds the potential to become a universal preprocessing step in the realm of high-performance QD optoelectronic devices.

14.
J Cell Mol Med ; 28(7): e18184, 2024 04.
Article in English | MEDLINE | ID: mdl-38509745

ABSTRACT

The optimal analgesia regimen after open cardiac surgery is unclear. The aim of this study was to investigate the beneficial effects of continuous transversus thoracis muscle plane (TTMP) blocks initiated before surgery on open cardiac surgery outcomes. A group of 110 patients were randomly allocated to either receive bilateral continuous TTMP blocks (TTP group) or no nerve block (SAL group). The primary endpoint was post-operative pain at 4, 8, 16, 24, 48 and 72 h after extubation at rest and exercise. The secondary outcome measures included analgesia requirements (sufentanil and flurbiprofen axetil administration), time to extubation, incidence of reintubation, length of stay in the ICU, incidence of post-operative nausea and vomiting (PONV), time until return of bowel function, time to mobilization, urinary catheter removal and length of hospital stay. The length of stay in the ICU and length of hospital stay were significantly longer in the SAL group than in the TTP group. NRS scores at rest and exercise were significantly lower in the TTP group than in the SAL group at all time points. The TTP group required significantly less intraoperative and post-operative sufentanil and post-operative dynastat consumption than the SAL group. Time to extubation, time to first flatus, time until mobilization and time until urinary catheter removal were significantly earlier in the TTP group than in the SAL group. The incidence of PONV was significantly lower in the TTP group. Bilateral continuous TTMP blocks provide effective analgesia and accelerate recovery in patients undergoing open heart valve replacement surgery.


Subject(s)
Cardiac Surgical Procedures , Sufentanil , Humans , Sufentanil/therapeutic use , Postoperative Nausea and Vomiting/chemically induced , Heart Valves , Muscles , Analgesics, Opioid
15.
J Am Chem Soc ; 146(7): 4632-4641, 2024 Feb 21.
Article in English | MEDLINE | ID: mdl-38340061

ABSTRACT

As fuel and an important chemical feedstock, n-propanol is highly desired in electrochemical CO2/CO reduction on Cu catalysts. However, the precise regulation of the Cu localized structure is still challenging and poorly understood, thus hindering the selective n-propanol electrosynthesis. Herein, by decorating Au nanoparticles (NPs) on CuO nanosheets (NSs), we present a counterintuitive transformation of CuO into undercoordinated Cu sites locally around Au NPs during CO reduction. In situ spectroscopic techniques reveal the Au-steered formation of abundant undercoordinated Cu sites during the removal of oxygen on CuO. First-principles accuracy molecular dynamic simulation demonstrates that the localized Cu atoms around Au tend to rearrange into disordered layer rather than a Cu (111) close-packed plane observed on bare CuO NSs. These Au-steered undercoordinated Cu sites facilitate CO binding, enabling selective electroreduction of CO into n-propanol with a high Faradaic efficiency of 48% in a flow cell. This work provides new insight into the regulation of the oxide-derived catalysts reconstruction with a secondary metal component.

16.
Neurobiol Dis ; 200: 106606, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39019292

ABSTRACT

The gut microbiota produces metabolites that enrich the host metabolome and play a part in host physiology, including brain functions. Yet the biological mediators of this gut-brain signal transduction remain largely unknown. In this study, the possible role of the gut microbiota metabolite indole, originating from tryptophan, was investigated. Oral administration of indole to simulate microbial overproduction of this compound in the gut consistently led to impaired locomotion and anxiety-like behaviour in both C3H/HeN and C57BL/6J mice. By employing c-Fos protein expression mapping in mice, we observed a noticeable increase in brain activation within the dorsal motor nucleus of the vagus nerve (DMX) and the locus coeruleus (LC) regions in a dose-dependent manner. Further immune co-labelling experiments elucidated that the primary cells activated within the LC were tyrosine hydroxylase positive. To delve deeper into the mechanistic aspects, we conducted chemogenetic activation experiments on LC norepinephrine neurons with two doses of clozapine N-oxide (CNO). Low dose of CNO at 0.5 mg/kg induced no change in locomotion but anxiety-like behaviour, while high dose of CNO at 2 mg/kg resulted in locomotion impairment and anxiety-like behaviour. These findings support the neuroactive roles of indole in mediating gut-brain communication. It also highlights the LC as a novel hub in the gut-brain axis, encouraging further investigations.

17.
Int J Cancer ; 155(7): 1316-1326, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-38769763

ABSTRACT

Ovarian cancer (OC) is a major cause of cancer mortality in women worldwide. Due to the occult onset of OC, its nonspecific clinical symptoms in the early phase, and a lack of effective early diagnostic tools, most OC patients are diagnosed at an advanced stage. In this study, shallow whole-genome sequencing was utilized to characterize fragmentomics features of circulating tumor DNA (ctDNA) in OC patients. By applying a machine learning model, multiclass fragmentomics data achieved a mean area under the curve (AUC) of 0.97 (95% CI 0.962-0.976) for diagnosing OC. OC scores derived from this model strongly correlated with the disease stage. Further comparative analysis of OC scores illustrated that the fragmentomics-based technology provided additional clinical benefits over the traditional serum biomarkers cancer antigen 125 (CA125) and the Risk of Ovarian Malignancy Algorithm (ROMA) index. In conclusion, fragmentomics features in ctDNA are potential biomarkers for the accurate diagnosis of OC.


Subject(s)
Biomarkers, Tumor , Circulating Tumor DNA , Machine Learning , Ovarian Neoplasms , Humans , Female , Ovarian Neoplasms/diagnosis , Ovarian Neoplasms/blood , Ovarian Neoplasms/genetics , Biomarkers, Tumor/blood , Biomarkers, Tumor/genetics , Circulating Tumor DNA/blood , Circulating Tumor DNA/genetics , Middle Aged , CA-125 Antigen/blood , Aged , Whole Genome Sequencing/methods , Adult , Algorithms , Area Under Curve
18.
Antimicrob Agents Chemother ; : e0012424, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38690893

ABSTRACT

As an obligate aerobe, Mycobacterium tuberculosis relies on its branched electron transport chain (ETC) for energy production through oxidative phosphorylation. Regimens targeting ETC exhibit promising potential to enhance bactericidal activity against M. tuberculosis and hold the prospect of shortening treatment duration. Our previous research demonstrated that the bacteriostatic drug candidate TB47 (T) inhibited the growth of M. tuberculosis by targeting the cytochrome bc1 complex and exhibited synergistic activity with clofazimine (C). Here, we found synergistic activities between C and sudapyridine (S), a structural analog of bedaquiline (B). S has shown similar anti-tuberculosis efficacy and may share a mechanism of action with B, which inhibits ATP synthesis and the energy metabolism of bacteria. We evaluated the efficacy of SCT in combination with linezolid (L) or pyrazinamide (Z) using a well-established murine model of tuberculosis. Compared to the BPa(pretomanid)L regimen, SCT and SCTL demonstrated similar bactericidal and sterilizing activities. There was no significant difference in activity between SCT and SCTL. In contrast, SCZ and SCTZ showed much higher activities, with none of the 15 mice experiencing relapse after 2 months of treatment with either SCZ or SCTZ. However, T did not contribute to the activity of the SCZ. Our findings emphasize the efficacy and the potential clinical significance of combination therapy with ETC inhibitors. Additionally, cross-resistance exists not only between S and B but also between S/B and C. This is supported by our findings, as spontaneous S-resistant mutants exhibited mutations in Rv0678, which are associated with cross-resistance to B and C.

19.
Ann Surg ; 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38323410

ABSTRACT

OBJECTIVE: Current study aims to investigate whether serum exosomal microRNAs (miRNAs) could be potential biomarkers in predicting APs with POF at early phase. BACKGROUND: Novel biomarkers are sorely needed for early prediction of persistent organ failure (POF) in acute pancreatitis (AP) patients. METHODS: In the discovery stage, exosomal miRNAs were profiled in sera from APs with or without POF (5 vs. 5) using microarrays. POF-associated miRNA signatures then were assessed in training cohort (n=227) and further validated in three independent cohorts (n=516), including one nested case-control cohort. RESULTS: A total of 743 APs were recruited in this large-scale biomarker identification study with a nested case-control study. Data from the discovery cohort demonstrated that 90 exosomal miRNAs were significantly dysregulated in APs with POF compared with controls. One miRNA classifier (Cmi) comprising 3 miRNAs (miR-4265, 1208, 3127-5p) was identified in the training cohort, and was further evaluated in two validation cohorts for their predictive value for POF. AUCs for Cmi ranged from 0.88 to 0.90, which was statistically superior to AUCs of APACHE-II and BISAP, and outperformed BUN and creatinine in POF prediction across all cohorts (P<.05). Higher levels of Cmi indicated increased need for ICU admission, prolonged hospitalization, and elevated mortality rate, thus poor prognosis. In the nested case-control study, Cmi could help identify prediagnostic POF in post-ERCP pancreatitis cases within "golden hours" after ERCP with high efficacy. CONCLUSIONS: Serum exosomal Cmi may be an early predictor for POF in AP, even within "golden hours" after AP onset. TRIAL REGISTRATION: ClinicalTrials.gov (NCT02602808).

20.
Anal Chem ; 96(2): 721-729, 2024 01 16.
Article in English | MEDLINE | ID: mdl-38176009

ABSTRACT

Accurate point-of-care (POC) analysis of cancer markers is the essence in the comprehensive early screening and treatment of cancer. Dual-mode synchronous detection is one of the effective approaches to reduce the probability of false negatives or false positives. As a result, this can greatly improve the accuracy of diagnosis. In this work, a surface-enhanced Raman scattering (SERS)-temperature dual-mode T-type lateral flow strip was fabricated to direct and simultaneous POC detection of total and free prostate-specific antigens (t-PSA and f-PSA) in blood. With the advantage of high stability of T-type lateral flow strip and simultaneous acquirement of assay results for t-PSA and f:t PSA ratio, the proposed method has high accuracy in the diagnosis of prostate cancer, especially in the diagnostic gray zone between 4.0 and 10.0 ng/mL. The SERS-temperature dual-signal has a good linear correlation with either f-PSA or t-PSA. To evaluate the clinical diagnostic performance of the proposed method, spiked human serum samples and the whole blood sample were analyzed. The assay results showed good recovery, and compared with traditional electrochemiluminescence immunoassay (ECLIA) method (t-PSA: 43.151; f/t ratio: 0.08), the results obtained by the proposed method were similar (t-PSA: 40.15 (SERS), 36.21 (temperature); f/t ratio: 0.08 (SERS), 0.08 (temperature), but the detection time (15 min) and cost ($0.05) had been greatly reduced. Therefore, the proposed SERS-temperature synchronous dual-mode T-type lateral flow strip has a strong application potential in the field of accurate large-scale diagnostics of prostate cancer on-site by simultaneous POC detection of t-PSA and f-PSA in blood.


Subject(s)
Prostate-Specific Antigen , Prostatic Neoplasms , Male , Humans , Prostate-Specific Antigen/analysis , Prostate/chemistry , Temperature , Prostatic Neoplasms/diagnosis , Immunoassay/methods
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