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1.
Cell ; 184(3): 775-791.e14, 2021 02 04.
Article in English | MEDLINE | ID: mdl-33503446

ABSTRACT

The molecular pathology of multi-organ injuries in COVID-19 patients remains unclear, preventing effective therapeutics development. Here, we report a proteomic analysis of 144 autopsy samples from seven organs in 19 COVID-19 patients. We quantified 11,394 proteins in these samples, in which 5,336 were perturbed in the COVID-19 patients compared to controls. Our data showed that cathepsin L1, rather than ACE2, was significantly upregulated in the lung from the COVID-19 patients. Systemic hyperinflammation and dysregulation of glucose and fatty acid metabolism were detected in multiple organs. We also observed dysregulation of key factors involved in hypoxia, angiogenesis, blood coagulation, and fibrosis in multiple organs from the COVID-19 patients. Evidence for testicular injuries includes reduced Leydig cells, suppressed cholesterol biosynthesis, and sperm mobility. In summary, this study depicts a multi-organ proteomic landscape of COVID-19 autopsies that furthers our understanding of the biological basis of COVID-19 pathology.


Subject(s)
COVID-19/metabolism , Gene Expression Regulation , Proteome/biosynthesis , Proteomics , SARS-CoV-2/metabolism , Autopsy , COVID-19/pathology , COVID-19/therapy , Female , Humans , Male , Organ Specificity
2.
Cell ; 182(1): 59-72.e15, 2020 07 09.
Article in English | MEDLINE | ID: mdl-32492406

ABSTRACT

Early detection and effective treatment of severe COVID-19 patients remain major challenges. Here, we performed proteomic and metabolomic profiling of sera from 46 COVID-19 and 53 control individuals. We then trained a machine learning model using proteomic and metabolomic measurements from a training cohort of 18 non-severe and 13 severe patients. The model was validated using 10 independent patients, 7 of which were correctly classified. Targeted proteomics and metabolomics assays were employed to further validate this molecular classifier in a second test cohort of 19 COVID-19 patients, leading to 16 correct assignments. We identified molecular changes in the sera of COVID-19 patients compared to other groups implicating dysregulation of macrophage, platelet degranulation, complement system pathways, and massive metabolic suppression. This study revealed characteristic protein and metabolite changes in the sera of severe COVID-19 patients, which might be used in selection of potential blood biomarkers for severity evaluation.


Subject(s)
Coronavirus Infections/blood , Metabolomics , Pneumonia, Viral/blood , Proteomics , Adult , Amino Acids/metabolism , Biomarkers/blood , COVID-19 , Cluster Analysis , Coronavirus Infections/physiopathology , Female , Humans , Lipid Metabolism , Machine Learning , Macrophages/pathology , Male , Middle Aged , Pandemics , Pneumonia, Viral/physiopathology , Severity of Illness Index
3.
Nat Immunol ; 23(4): 594-604, 2022 04.
Article in English | MEDLINE | ID: mdl-35354951

ABSTRACT

While T cell receptor (TCR) αß+CD8α+CD8ß- intraepithelial lymphocytes (CD8αα+ IELs) differentiate from thymic IEL precursors (IELps) and contribute to gut homeostasis, the transcriptional control of their development remains poorly understood. In the present study we showed that mouse thymocytes deficient for the transcription factor leukemia/lymphoma-related factor (LRF) failed to generate TCRαß+CD8αα+ IELs and their CD8ß-expressing counterparts, despite giving rise to thymus and spleen CD8αß+ T cells. LRF-deficient IELps failed to migrate to the intestine and to protect against T cell-induced colitis, and had impaired expression of the gut-homing integrin α4ß7. Single-cell RNA-sequencing found that LRF was necessary for the expression of genes characteristic of the most mature IELps, including Itgb7, encoding the ß7 subunit of α4ß7. Chromatin immunoprecipitation and gene-regulatory network analyses both defined Itgb7 as an LRF target. Our study identifies LRF as an essential transcriptional regulator of IELp maturation in the thymus and subsequent migration to the intestinal epithelium.


Subject(s)
Intraepithelial Lymphocytes , Leukemia , Lymphoma , Animals , CD8 Antigens/genetics , CD8 Antigens/metabolism , CD8-Positive T-Lymphocytes/metabolism , Integrin beta Chains , Intestinal Mucosa/metabolism , Intraepithelial Lymphocytes/metabolism , Leukemia/metabolism , Lymphoma/metabolism , Mice , Mice, Knockout , Receptors, Antigen, T-Cell, alpha-beta/genetics , Receptors, Antigen, T-Cell, alpha-beta/metabolism , Transcription Factors/metabolism
4.
Nature ; 618(7963): 102-109, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37225985

ABSTRACT

Parasitic nematodes are a major threat to global food security, particularly as the world amasses 10 billion people amid limited arable land1-4. Most traditional nematicides have been banned owing to poor nematode selectivity, leaving farmers with inadequate means of pest control4-12. Here we use the model nematode Caenorhabditis elegans to identify a family of selective imidazothiazole nematicides, called selectivins, that undergo cytochrome-p450-mediated bioactivation in nematodes. At low parts-per-million concentrations, selectivins perform comparably well with commercial nematicides to control root infection by Meloidogyne incognita, a highly destructive plant-parasitic nematode. Tests against numerous phylogenetically diverse non-target systems demonstrate that selectivins are more nematode-selective than most marketed nematicides. Selectivins are first-in-class bioactivated nematode controls that provide efficacy and nematode selectivity.


Subject(s)
Antinematodal Agents , Tylenchoidea , Animals , Humans , Antinematodal Agents/chemistry , Antinematodal Agents/metabolism , Antinematodal Agents/pharmacology , Caenorhabditis elegans/drug effects , Caenorhabditis elegans/metabolism , Tylenchoidea/drug effects , Tylenchoidea/metabolism , Thiazoles/chemistry , Thiazoles/metabolism , Thiazoles/pharmacology , Cytochrome P-450 Enzyme System/drug effects , Plant Roots/drug effects , Plant Roots/parasitology , Plant Diseases , Species Specificity , Substrate Specificity
5.
Immunity ; 51(3): 465-478.e6, 2019 09 17.
Article in English | MEDLINE | ID: mdl-31422869

ABSTRACT

The generation of high-affinity neutralizing antibodies, the objective of most vaccine strategies, occurs in B cells within germinal centers (GCs) and requires rate-limiting "help" from follicular helper CD4+ T (Tfh) cells. Although Tfh differentiation is an attribute of MHC II-restricted CD4+ T cells, the transcription factors driving Tfh differentiation, notably Bcl6, are not restricted to CD4+ T cells. Here, we identified a requirement for the CD4+-specific transcription factor Thpok during Tfh cell differentiation, GC formation, and antibody maturation. Thpok promoted Bcl6 expression and bound to a Thpok-responsive region in the first intron of Bcl6. Thpok also promoted the expression of Bcl6-independent genes, including the transcription factor Maf, which cooperated with Bcl6 to mediate the effect of Thpok on Tfh cell differentiation. Our findings identify a transcriptional program that links the CD4+ lineage with Tfh differentiation, a limiting factor for efficient B cell responses, and suggest avenues to optimize vaccine generation.


Subject(s)
Cell Differentiation/immunology , Proto-Oncogene Proteins c-bcl-6/immunology , Proto-Oncogene Proteins c-maf/immunology , T-Lymphocytes, Helper-Inducer/immunology , Transcription Factors/immunology , Transcription, Genetic/immunology , Animals , Antibodies, Neutralizing/immunology , B-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/immunology , Female , Gene Expression Regulation/immunology , Germinal Center/immunology , Lymphocyte Activation/immunology , Mice , Mice, Inbred C57BL
6.
Nat Methods ; 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38965442

ABSTRACT

Dynamic imaging of genomic loci is key for understanding gene regulation, but methods for imaging genomes, in particular non-repetitive DNAs, are limited. We developed CRISPRdelight, a DNA-labeling system based on endonuclease-deficient CRISPR-Cas12a (dCas12a), with an engineered CRISPR array to track DNA location and motion. CRISPRdelight enables robust imaging of all examined 12 non-repetitive genomic loci in different cell lines. We revealed the confined movement of the CCAT1 locus (chr8q24) at the nuclear periphery for repressed expression and active motion in the interior nucleus for transcription. We uncovered the selective repositioning of HSP gene loci to nuclear speckles, including a remarkable relocation of HSPH1 (chr13q12) for elevated transcription during stresses. Combining CRISPR-dCas12a and RNA aptamers allowed multiplex imaging of four types of satellite DNA loci with a single array, revealing their spatial proximity to the nucleolus-associated domain. CRISPRdelight is a user-friendly and robust system for imaging and tracking genomic dynamics and regulation.

7.
PLoS Pathog ; 20(1): e1011918, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38241414

ABSTRACT

Bacterial persister cells, a sub-population of dormant phenotypic variants highly tolerant to antibiotics, present a significant challenge for infection control. Investigating the mechanisms of antibiotic persistence is crucial for developing effective treatment strategies. Here, we found a significant association between tolerance frequency and previous infection history in bovine mastitis. Previous S. aureus infection led to S. aureus tolerance to killing by rifampicin in subsequent infection in vivo and in vitro. Actually, the activation of trained immunity contributed to rifampicin persistence of S. aureus in secondary infection, where it reduced the effectiveness of antibiotic treatment and increased disease severity. Mechanically, we found that S. aureus persistence was mediated by the accumulation of fumarate provoked by trained immunity. Combination therapy with metformin and rifampicin promoted eradication of persisters and improved the severity of recurrent S. aureus infection. These findings provide mechanistic insight into the relationship between trained immunity and S. aureus persistence, while providing proof of concept that trained immunity is a therapeutic target in recurrent bacterial infections involving persistent pathogens.


Subject(s)
Staphylococcal Infections , Staphylococcus aureus , Animals , Female , Cattle , Staphylococcus aureus/physiology , Rifampin/pharmacology , Rifampin/therapeutic use , Trained Immunity , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Bacteria
8.
Nature ; 588(7837): 284-289, 2020 12.
Article in English | MEDLINE | ID: mdl-33239781

ABSTRACT

Genetic diversity is key to crop improvement. Owing to pervasive genomic structural variation, a single reference genome assembly cannot capture the full complement of sequence diversity of a crop species (known as the 'pan-genome'1). Multiple high-quality sequence assemblies are an indispensable component of a pan-genome infrastructure. Barley (Hordeum vulgare L.) is an important cereal crop with a long history of cultivation that is adapted to a wide range of agro-climatic conditions2. Here we report the construction of chromosome-scale sequence assemblies for the genotypes of 20 varieties of barley-comprising landraces, cultivars and a wild barley-that were selected as representatives of global barley diversity. We catalogued genomic presence/absence variants and explored the use of structural variants for quantitative genetic analysis through whole-genome shotgun sequencing of 300 gene bank accessions. We discovered abundant large inversion polymorphisms and analysed in detail two inversions that are frequently found in current elite barley germplasm; one is probably the product of mutation breeding and the other is tightly linked to a locus that is involved in the expansion of geographical range. This first-generation barley pan-genome makes previously hidden genetic variation accessible to genetic studies and breeding.


Subject(s)
Chromosomes, Plant/genetics , Genome, Plant/genetics , Hordeum/genetics , Internationality , Mutation , Plant Breeding , Chromosome Inversion/genetics , Chromosome Mapping , Genetic Loci/genetics , Genotype , Hordeum/classification , Polymorphism, Genetic/genetics , Reference Standards , Seed Bank , Sequence Inversion , Whole Genome Sequencing
9.
Exp Cell Res ; 438(1): 114052, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38636651

ABSTRACT

Trained immunity is mechanistically defined as the metabolically and epigenetically mediated long-term functional adaptation of the innate immune system, characterized by a heightened response to a secondary stimulation. Given appropriate activation, trained immunity represents an attractive anti-infective therapeutic target. Nevertheless, excessive immune response and subsequent inflammatory cascades may contribute to pathological tissue damage, indicating that the negative impacts of trained immunity appear to be significant. In this study, we show that innate immune responses such as the production of extracellular traps, pro-inflammatory cytokines, and autophagy-related proteins were markedly augmented in trained BMDMs. Furthermore, heat-killed C. albicans priming promotes the activation of the AIM2 inflammasome, and AIM2-/- mice exhibit impaired memory response induced by heat-killed C. albicans. Therefore, we establish that the AIM2 inflammasome is involved in trained immunity and emerges as a promising therapeutic target for potentially deleterious effects. Dihydroartemisinin can inhibit the memory response induced by heat-killed C. albicans through modulation of mTOR signaling and the AIM2 inflammasome. The findings suggest that dihydroartemisinin can reduce the induction of trained immunity by heat-killed C. albicans in C57BL/6 mice. Dihydroartemisinin is one such therapeutic intervention that has the potential to treat of diseases characterized by excessive trained immunity.


Subject(s)
Artemisinins , Proto-Oncogene Proteins c-akt , Signal Transduction , TOR Serine-Threonine Kinases , Trained Immunity , Animals , Mice , Artemisinins/pharmacology , Candida albicans/drug effects , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Inflammasomes/metabolism , Inflammasomes/drug effects , Mice, Inbred C57BL , Mice, Knockout , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/drug effects , TOR Serine-Threonine Kinases/metabolism , Trained Immunity/drug effects
10.
J Infect Dis ; 229(1): 117-121, 2024 Jan 12.
Article in English | MEDLINE | ID: mdl-37565805

ABSTRACT

Using a prospective, observational cohort study during the post-"dynamic COVID-zero" wave in China, we estimated short-term relative effectiveness against Omicron BA.5 infection of inhaled aerosolized adenovirus type 5-vectored ancestral strain coronavirus disease 2019 (COVID-19) vaccine as a second booster dose approximately 1 year after homologous boosted primary series of inactivated COVID-19 vaccine compared with no second booster. Participants reported nucleic acid or antigen test results weekly until they tested positive or completed predesignated follow-up. After excluding participants infected <14 days after study entry, relative effectiveness among the 6576 participants was 61% in 18- to 59-year-olds and 38% in ≥60-year-olds and was sustained for 12 weeks.


Subject(s)
COVID-19 Vaccines , COVID-19 , Humans , COVID-19/prevention & control , Prospective Studies , Vaccine Efficacy , China/epidemiology , Adenoviridae/genetics
11.
J Am Chem Soc ; 146(33): 22869-22873, 2024 Aug 21.
Article in English | MEDLINE | ID: mdl-39115272

ABSTRACT

Tubular structures exist broadly in biological systems and exhibit important functions including mediating cellular communications. The construction of artificial analogues in living cells would provide a new strategy for chemotherapy. In this report, a kind of supramolecular channel has been constructed within intercellular gaps by mimicking the assembly process and structure of natural gap junctional channels, which consist of hydrophobic tubular modules located in the adjacent cell membranes and hydrophilic modules within the extracellular space. The assembly of the channels was driven by electrostatic interactions. The channels could inhibit tumor cell invasion by preventing cell migration.


Subject(s)
Cell Movement , Humans , Cell Movement/drug effects , Gap Junctions/metabolism , Hydrophobic and Hydrophilic Interactions , Ion Channels/metabolism , Ion Channels/chemistry , Cell Line, Tumor
12.
Gastroenterology ; 165(3): 629-646, 2023 09.
Article in English | MEDLINE | ID: mdl-37247644

ABSTRACT

BACKGROUND & AIMS: Hyperactivation of ribosome biogenesis leads to hepatocyte transformation and plays pivotal roles in hepatocellular carcinoma (HCC) development. We aimed to identify critical ribosome biogenesis proteins that are overexpressed and crucial in HCC progression. METHODS: HEAT repeat containing 1 (HEATR1) expression and clinical correlations were analyzed using The Cancer Genome Atlas and Gene Expression Omnibus databases and further evaluated by immunohistochemical analysis of an HCC tissue microarray. Gene expression was knocked down by small interfering RNA. HEATR1-knockdown cells were subjected to viability, cell cycle, and apoptosis assays and used to establish subcutaneous and orthotopic tumor models. Chromatin immunoprecipitation and quantitative polymerase chain reaction were performed to detect the association of candidate proteins with specific DNA sequences. Endogenous coimmunoprecipitation combined with mass spectrometry was used to identify protein interactions. We performed immunoblot and immunofluorescence assays to detect and localize proteins in cells. The nucleolus ultrastructure was detected by transmission electron microscopy. Click-iT (Thermo Fisher Scientific) RNA imaging and puromycin incorporation assays were used to measure nascent ribosomal RNA and protein synthesis, respectively. Proteasome activity, 20S proteasome foci formation, and protein stability were evaluated in HEATR1-knockdown HCC cells. RESULTS: HEATR1 was the most up-regulated gene in a set of ribosome biogenesis mediators in HCC samples. High expression of HEATR1 was associated with poor survival and malignant clinicopathologic features in patients with HCC and contributed to HCC growth in vitro and in vivo. HEATR1 expression was regulated by the transcription factor specificity protein 1, which can be activated by insulin-like growth factor 1-mammalian target of rapamycin complex 1 signaling in HCC cells. HEATR1 localized predominantly in the nucleolus, bound to ribosomal DNA, and was associated with RNA polymerase I transcription/processing factors. Knockdown of HEATR1 disrupted ribosomal RNA biogenesis and impaired nascent protein synthesis, leading to reduced cytoplasmic proteasome activity and inhibitory-κB/nuclear factor-κB signaling. Moreover, HEATR1 knockdown induced nucleolar stress with increased nuclear proteasome activity and inactivation of the nucleophosmin 1-MYC axis. CONCLUSIONS: Our study revealed that HEATR1 is up-regulated by insulin-like growth factor 1-mammalian target of rapamycin complex 1-specificity protein 1 signaling in HCC and functions as a crucial regulator of ribosome biogenesis and proteome homeostasis to promote HCC development.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Cell Proliferation/genetics , Gene Expression Regulation, Neoplastic , Homeostasis , Hot Temperature , Insulin-Like Growth Factor I/genetics , Liver Neoplasms/pathology , Mechanistic Target of Rapamycin Complex 1/metabolism , Proteasome Endopeptidase Complex/genetics , Proteome/metabolism , Ribosomes/metabolism , Ribosomes/pathology , RNA, Ribosomal/genetics , RNA, Ribosomal/metabolism
13.
Anal Chem ; 96(10): 4129-4137, 2024 03 12.
Article in English | MEDLINE | ID: mdl-38469639

ABSTRACT

Long-term continuous imaging of endogenous HClO burst is of great importance for the elucidation of various physiological or pathological processes. However, most of the currently reported HClO probes have failed to achieve this goal due to their insufficient photobleaching resistance under a laser source. Herein, a highly stable ratiometric probe, HFTC-HClO 1, which is capable of continuously monitoring endogenous HClO burst over a long period of time, has been judiciously developed. Briefly, the de novo development of HFTC-HClO 1 mainly involved three main steps: (1) novel coumarins (HFTC 1-5) were designed and synthesized; (2) the most stable scaffold, HFTC 3, was selected through dye screening and cell imaging validation; and (3) based on HFTC 3, three candidate HClO probes were constructed, and HFTC-HClO 1 was finally selected due to its superior sensing properties toward HClO. Furthermore, HFTC-HClO 1 can quantitatively measure HClO levels in various real samples with excellent recovery (>90.4%), and the use of HFTC-HClO 1-coated test strips for qualitative analysis of HClO in real samples was also achieved. In addition, the application of HFTC-HClO 1 for long-term continuous monitoring of intracellular HClO burst was successfully demonstrated. Significantly, HFTC-HClO 1 was able to visualize HClO generated in the rheumatoid arthritis mouse model.


Subject(s)
Fluorescent Dyes , Hypochlorous Acid , Mice , Animals , Hypochlorous Acid/analysis , Microscopy, Fluorescence/methods , Optical Imaging/methods , Coumarins
14.
Anal Chem ; 96(18): 7082-7090, 2024 05 07.
Article in English | MEDLINE | ID: mdl-38652135

ABSTRACT

Parkinson's disease (PD) represents the second most widespread neurodegenerative disease, and early monitoring and diagnosis are urgent at present. Tyrosine hydroxylase (TH) is a key enzyme for producing dopamine, the levels of which can serve as an indicator for assessing the severity and progression of PD. This renders the specific detection and visualization of TH a strategically vital way to meet the above demands. However, a fluorescent probe for TH monitoring is still missing. Herein, three rationally designed wash-free ratiometric fluorescent probes were proposed. Among them, TH-1 exhibited ideal photophysical properties and specific dual-channel bioimaging of TH activity in SH-SY5Y nerve cells. Moreover, the probe allowed for in vivo imaging of TH activity in zebrafish brain and living striatal slices of mice. Overall, the ratiometric fluorescent probe TH-1 could serve as a potential tool for real-time monitoring of PD in complex biosystems.


Subject(s)
Fluorescent Dyes , Tyrosine 3-Monooxygenase , Zebrafish , Fluorescent Dyes/chemistry , Fluorescent Dyes/chemical synthesis , Tyrosine 3-Monooxygenase/metabolism , Tyrosine 3-Monooxygenase/analysis , Animals , Mice , Humans , Optical Imaging , Cell Line, Tumor , Parkinson Disease/diagnostic imaging , Parkinson Disease/metabolism
15.
Anal Chem ; 96(29): 11915-11922, 2024 07 23.
Article in English | MEDLINE | ID: mdl-39007441

ABSTRACT

G-quadruplex structures within the nuclear genome (nG4) is an important regulatory factor, while the function of G4 in the mitochondrial genome (mtG4) still needs to be explored, especially in human sperms. To gain a better understanding of the relationship between mtG4 and mitochondrial function, it is crucial to develop excellent probes that can selectively visualize and track mtG4 in both somatic cells and sperms. Herein, based on our previous research on purine frameworks, we attempted for the first time to extend the conjugated structure from the C-8 site of purine skeleton and discovered that the purine derivative modified by the C-8 aldehyde group is an ideal platform for constructing near-infrared probes with extremely large Stokes shift (>220 nm). Compared with the compound substituted with methylpyridine (PAP), the molecule substituted with methylthiazole orange (PATO) showed better G4 recognition ability, including longer emission (∼720 nm), more significant fluorescent enhancement (∼67-fold), lower background, and excellent photostability. PATO exhibited a sensitive response to mtG4 variation in both somatic cells and human sperms. Most importantly, PATO helped us to discover that mtG4 was significantly increased in cells with mitochondrial respiratory chain damage caused by complex I inhibitors (6-OHDA and rotenone), as well as in human sperms that suffer from oxidative stress. Altogether, our study not only provides a novel ideal molecular platform for constructing high-performance probes but also develops an effective tool for studying the relationship between mtG4 and mitochondrial function in both somatic cells and human sperms.


Subject(s)
Fluorescent Dyes , Purines , Humans , Purines/chemistry , Fluorescent Dyes/chemistry , Fluorescent Dyes/chemical synthesis , Mitochondrial Diseases/metabolism , Up-Regulation , Genome, Mitochondrial , G-Quadruplexes , Mitochondria/metabolism , Infrared Rays , HeLa Cells
16.
Nat Mater ; 22(4): 429-433, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36894771

ABSTRACT

The lowest-lying fundamental excitation of an incommensurate charge-density-wave material is believed to be a massless phason-a collective modulation of the phase of the charge-density-wave order parameter. However, long-range Coulomb interactions should push the phason energy up to the plasma energy of the charge-density-wave condensate, resulting in a massive phason and fully gapped spectrum1. Using time-domain terahertz emission spectroscopy, we investigate this issue in (TaSe4)2I, a quasi-one-dimensional charge-density-wave insulator. On transient photoexcitation at low temperatures, we find the material strikingly emits coherent, narrowband terahertz radiation. The frequency, polarization and temperature dependences of the emitted radiation imply the existence of a phason that acquires mass by coupling to long-range Coulomb interactions. Our observations underscore the role of long-range interactions in determining the nature of collective excitations in materials with modulated charge or spin order.

17.
Chemistry ; 30(8): e202303519, 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38018776

ABSTRACT

Three unusual ajmaline-macroline type bisindole alkaloids, alsmaphylines A-C, together with their postulated biogenetic precursors, were isolated from the stem barks and leaves of Alstonia macrophylla via the building blocks-based molecular network (BBMN) strategy. Alsmaphyline A represents a rare ajmaline-macroline type bisindole alkaloid with an S-shape polycyclic ring system. Alsmaphylines B and C are two novel ajmaline-macroline type bisindole alkaloids with N-1-C-21' linkages, and the former possesses an unconventional stacked conformation due to the presence of intramolecular noncovalent interactions. The chemical structures including absolute configurations of alsmaphylines A-C were established by comprehensive spectroscopic analyses, electronic circular dichroism (ECD) calculations, and single-crystal X-ray crystallography. In addition, a plausible biosynthetic pathway of these bisindole alkaloids as well as their ability to promote the protein synthesis on HT22 cells were discussed.


Subject(s)
Alkaloids , Alstonia , Oxindoles , Alstonia/chemistry , Ajmaline , Indole Alkaloids/chemistry , Molecular Structure , Alkaloids/chemistry
18.
Mol Pharm ; 21(4): 2012-2024, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38497779

ABSTRACT

The nonviral delivery systems that combine genes with photosensitizers for multimodal tumor gene/photodynamic therapy (PDT) have attracted much attention. In this study, a series of ROS-sensitive cationic bola-lipids were applied for the gene/photosensitizer codelivery. Zn-DPA was introduced as a cationic headgroup to enhance DNA binding, while the hydrophobic linking chains may facilitate the formation of lipid nanoparticles (LNP) and the encapsulation of photosensitizer Ce6. The length of the hydrophobic chain played an important role in the gene transfection process, and 14-TDZn containing the longest chains showed better DNA condensation, gene transfection, and cellular uptake. 14-TDZn LNPs could well load photosensitizer Ce6 to form 14-TDC without a loss of gene delivery efficiency. 14-TDC was used for codelivery of p53 and Ce6 to achieve enhanced therapeutic effects on the tumor cell proliferation inhibition and apoptosis. Results showed that the codelivery system was more effective in the inhibition of tumor cell proliferation than individual p53 or Ce6 monotherapy. Mechanism studies showed that the production of ROS after Ce6 irradiation could increase the accumulation of p53 protein in tumor cells, thereby promoting caspase-3 activation and inducing apoptosis, indicating some synergistic effect. These results demonstrated that 14-TDC may serve as a promising nanocarrier for gene/PDT combination therapy.


Subject(s)
Liposomes , Nanoparticles , Photochemotherapy , Porphyrins , Photosensitizing Agents/chemistry , Photochemotherapy/methods , Reactive Oxygen Species/metabolism , Tumor Suppressor Protein p53/genetics , Cell Line, Tumor , Nanoparticles/chemistry , DNA , Porphyrins/chemistry
19.
Langmuir ; 40(1): 1007-1015, 2024 01 09.
Article in English | MEDLINE | ID: mdl-38117735

ABSTRACT

The trade-off that shorter wavelength light facilitates the efficient generation of reactive oxygen species (ROS) from photosensitizer (PS) while facing the drawback of limited penetration depth through skin tissue restricts the further development of photodynamic therapy (PDT). Here, we address this contradiction and achieve visible-light-tailored deep PDT combined with the skin optical clearing technology. With the help of the prepared skin optical clearing gel, the refractive index inhomogeneity between skin tissue components is greatly attenuated, and the light scattering effect within the skin tissue is remarkably reduced. As a consequence, the transmittance of visible light at 600 nm through in vitro porcine skin and in vivo mouse skin after treatment increases from approximately 10 and 40 to 70 and 70%, respectively. Furthermore, in the tumor cell eradication experiment, the local ROS generation efficiency in the experimental group is several times higher than that in the control group owing to improved visible transmittance, which is thus responsible for the complete eradication of tumor cells, even when shaded by skin tissue. The results suggest that this strategy may serve as a valuable supplement to the current deep PDT strategies.


Subject(s)
Photochemotherapy , Mice , Animals , Swine , Photochemotherapy/methods , Reactive Oxygen Species , Light , Skin , Photosensitizing Agents/pharmacology , Photosensitizing Agents/therapeutic use
20.
Langmuir ; 2024 Aug 26.
Article in English | MEDLINE | ID: mdl-39186791

ABSTRACT

The abuse of hazardous agrochemicals leads to excessive toxic agricultural emissions, posing a tremendous threat to the natural surroundings and human well-being. In practice, the amount of pesticides in protecting crops is often far less than that lost into the environment through evaporation and leaching. Minimizing the use of pesticides as well as improving their use efficiency has been included in the policy of "agricultural double reduction," besides replacing the chemical fertilizer with straw returning. Here, we establish a strategy for controlling pesticide release from the lignocellulosic waste based on the stimulus-responsive cleavage of silaketal linkages. Noting that the cleavage of the silaketal linkages relies heavily on the substituent groups on silicon atoms, this pesticide-releasing system has the advantages of predictable service life and less environmental pollution in a desired time window. Instead of lengthy laboratory synthesis, outdoor instant synthesis can be conveniently realized with the help of a photothermal heating apparatus. After utilization, both silaketal linkages and lignocellulosic residuals are eco-friendly and can be a source of nutrients for soil. Referring to agricultural double reduction, this type of pesticide formulation is coined as a competitive approach to minimize pesticide pollution along with straw returning.

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