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1.
PLoS Genet ; 18(6): e1010275, 2022 06.
Article in English | MEDLINE | ID: mdl-35696436

ABSTRACT

Timely completion of eukaryotic genome duplication requires coordinated DNA replication initiation at multiple origins. Replication begins with the loading of the Mini-Chromosome Maintenance (MCM) complex, proceeds by the activation of the Cdc45-MCM-GINS (CMG) helicase, and ends with CMG removal after chromosomes are fully replicated. Post-translational modifications on the MCM and associated factors ensure an orderly transit of these steps. Although the mechanisms of CMG activation and removal are partially understood, regulated MCM loading is not, leaving an incomplete understanding of how DNA replication begins. Here we describe a site-specific modification of Mcm3 by the Small Ubiquitin-like MOdifier (SUMO). Mutations that prevent this modification reduce the MCM loaded at replication origins and lower CMG levels, resulting in impaired cell growth, delayed chromosomal replication, and the accumulation of gross chromosomal rearrangements (GCRs). These findings demonstrate the existence of a SUMO-dependent regulation of origin-bound MCM and show that this pathway is needed to prevent genome rearrangements.


Subject(s)
DNA Replication , Sumoylation , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , DNA Helicases/genetics , DNA Replication/genetics , Minichromosome Maintenance Proteins/genetics , Minichromosome Maintenance Proteins/metabolism , Replication Origin/genetics , Sumoylation/genetics
2.
J Cell Biochem ; 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38860522

ABSTRACT

The importance of protein kinase B (AKT) in tumorigenesis and development is well established, but its potential regulation of metabolic reprogramming via phosphorylation of the hexokinase (HK) isozymes remains unclear. There are two HK family members (HK1/2) and three AKT family members (AKT1/2/3), with varied distribution of AKTs exhibiting distinct functions in different tissues and cell types. Although AKT is known to phosphorylate HK2 at threonine 473, AKT-mediated phosphorylation of HK1 has not been reported. We examined direct binding and phosphorylation of HK1/2 by AKT1 and identified the phosphorylation modification sites using coimmunoprecipitation, glutathione pull-down, western blotting, and in vitro kinase assays. Regulation of HK activity through phosphorylation by AKT1 was also examined. Uptake of 2-[1,2-3H]-deoxyglucose and production of lactate were investigated to determine whether AKT1 regulates glucose metabolism by phosphorylating HK1/2. Functional assays, immunohistochemistry, and tumor experiments in mice were performed to investigate whether AKT1-mediated regulation of tumor development is dependent on its kinase activity and/or the involvement of HK1/2. AKT interacted with and phosphorylated HK1 and HK2. Serine phosphorylation significantly increased AKT kinase activity, thereby enhancing glycolysis. Mechanistically, the phosphorylation of HK1 at serine 178 (S178) by AKT significantly decreased the Km and enhanced the Vmax by interfering with the formation of HK1 dimers. Mutations in the AKT phosphorylation sites of HK1 or HK2 significantly abrogated the stimulatory characteristics of AKT on glycolysis, tumorigenesis, and cell migration, invasion, proliferation, and metastasis. HK1-S178 phosphorylation levels were significantly correlated with the occurrence and metastasis of different types of clinical tumors. We conclude that AKT not only regulates tumor glucose metabolism by directly phosphorylating HK1 and HK2, but also plays important roles in tumor progression, proliferation, and migration.

3.
Small ; 20(7): e2306576, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37803924

ABSTRACT

The widespread acceptance of nonaqueous rechargeable metal-gas batteries, known for their remarkably high theoretical energy density, faces obstacles such as poor reversibility and low energy efficiency under high charge-discharge current densities. To tackle these challenges, a novel catalytic cathode architecture for Mg-CO2 batteries, fabricated using a one-pot electrospinning method followed by heat treatment, is presented. The resulting structure features well-dispersed molybdenum carbide nanodots embedded within interconnected carbon nanofibers, forming a 3D macroporous conducting network. This cathode design enhances the volumetric efficiency, enabling effective discharge product deposition, while also improving electrical properties and boosting catalytic activity. This enhancement results in high discharge capacities and excellent rate capabilities, while simultaneously minimizing voltage hysteresis and maximizing energy efficiency. The battery exhibits a stable cycle life of over 250 h at a current density of 200 mA g-1 with a low initial charge-discharge voltage gap of 0.72 V. Even at incredibly high current densities, reaching 1600 mA g-1 , the battery maintains exceptional performance. These findings highlight the crucial role of cathode architecture design in enhancing the performance of Mg-CO2 batteries and hold promise for improving other metal-gas batteries that involve deposition-decomposition reactions.

4.
Opt Lett ; 49(2): 338-341, 2024 Jan 15.
Article in English | MEDLINE | ID: mdl-38194555

ABSTRACT

Due to the low-power consumption, self-driven ultraviolet (UV) photodetectors have great potentials in a broad range of applications, such as optical communication, ozone monitoring, bio-medicine, and flame detection. In this Letter, it is pretty novel to enhance the photocurrent and responsivity of self-driven UV photodetectors by (Al,Ga)N nanowire/graphene/polyvinylidene fluoride (PVDF) heterojunction successfully. Compared to those of the photodetector with only nanowire/graphene heterojunction, it is found that both the photocurrent and responsivity of the photodetector with nanowire/graphene/PVDF heterojunction can be enhanced more than 100%. It is proposed that PVDF could maintain the internal gain by increasing the number of carrier cycles. Furthermore, this photodetector can also have a high detectivity of 5.3×1011 Jones and fast response speed under 310 nm illumination. After preserving for one month without any special protection, both photocurrent and responsivity of the photodetector with nanowire/graphene/PVDF heterojunction are demonstrated to be quite stable. Therefore, this work paves an effective way to improve the performance of photodetectors for their applications in the fields of next-generation optoelectronic devices.

5.
Nanotechnology ; 35(23)2024 Mar 18.
Article in English | MEDLINE | ID: mdl-38497449

ABSTRACT

Because of wide range of applications, the flexible artificial synapse is an indispensable part for next-generation neural morphology computing. In this work, we demonstrate a flexible synaptic device based on a lift-off (In,Ga)N thin film successfully. The synaptic device can mimic the learning, forgetting, and relearning functions of biological synapses at both flat and bent states. Furthermore, the synaptic device can simulate the transition from short-term memory to long-term memory successfully under different bending conditions. With the high flexibility, the excitatory post-synaptic current of the bent device only shows a slight decrease, leading to the high stability. Based on the experimental conductance for long-term potentiation and depression, the simulated three-layer neural network can achieve a high recognition rate up to 90.2%, indicating that the system comprising of flexible synaptic devices could have a strong learning-memory capability. Therefore, this work has a great potential for the development of wearable intelligence devices and flexible neuromorphic systems.


Subject(s)
Synapses , Wearable Electronic Devices , Neural Networks, Computer
6.
Proc Natl Acad Sci U S A ; 118(18)2021 May 04.
Article in English | MEDLINE | ID: mdl-33903240

ABSTRACT

Inorganic semiconductor-based microscale light-emitting diodes (micro-LEDs) have been widely considered the key solution to next-generation, ubiquitous lighting and display systems, with their efficiency, brightness, contrast, stability, and dynamic response superior to liquid crystal or organic-based counterparts. However, the reduction of micro-LED sizes leads to the deteriorated device performance and increased difficulties in manufacturing. Here, we report a tandem device scheme based on stacked red, green, and blue (RGB) micro-LEDs, for the realization of full-color lighting and displays. Thin-film micro-LEDs (size ∼100 µm, thickness ∼5 µm) based on III-V compound semiconductors are vertically assembled via epitaxial liftoff and transfer printing. A thin-film dielectric-based optical filter serves as a wavelength-selective interface for performance enhancement. Furthermore, we prototype arrays of tandem RGB micro-LEDs and demonstrate display capabilities. These materials and device strategies provide a viable path to advanced lighting and display systems.

7.
Genomics ; 115(2): 110574, 2023 03.
Article in English | MEDLINE | ID: mdl-36758878

ABSTRACT

Chondrocyte senescence is a decisive component of age-related osteoarthritis, however, the function of small noncoding RNAs (sncRNAs) in chondrocyte senescence remains underexplored. Human hip joint cartilage chondrocytes were cultivated up to passage 4 to induce senescence. RNA samples were extracted and then analyzed using small RNA sequencing and qPCR. ß-galactosidase staining was used to detect the effect of sncRNA on chondrocyte aging. Results of small RNA sequencing showed that 279 miRNAs, 136 snoRNAs, 30 snRNAs, 102 piRNAs, and 5 rasiRNAs were differentially expressed in senescent chondrocytes. The differential expression of 150 sncRNAs was further validated by qPCR. Transfection of sncRNAs and ß-galactosidase staining were also performed to further revealed that hsa-miR-135b-5p, SNORA80B-201, and RNU5E-1-201 have the function to restrain chondrocyte senescence, while has-piR-019102 has the function to promote chondrocyte senescence. Our data suggest that sncRNAs have therapeutic potential as novel epigenetic targets in age-related osteoarthritis.


Subject(s)
MicroRNAs , Osteoarthritis , RNA, Small Untranslated , Humans , Chondrocytes/metabolism , Osteoarthritis/genetics , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Small Untranslated/metabolism , beta-Galactosidase/genetics , beta-Galactosidase/metabolism , Epigenesis, Genetic , Cellular Senescence
8.
Nano Lett ; 23(22): 10625-10632, 2023 Nov 22.
Article in English | MEDLINE | ID: mdl-37930759

ABSTRACT

5-Hydroxymethyluracil (5hmU) is an oxidation derivative of thymine in the genomes of various organisms and may serve as both an epigenetic mark and a cancer biomarker. However, the current 5hmU assays usually have drawbacks of laborious procedures, low specificity, and unsatisfactory sensitivity. Herein, we demonstrate the click chemistry-mediated hyperbranched amplification-driven dendritic nanoassembly for genome-wide analysis of 5hmU in breast cell lines and human breast tissues. The proposed strategy possesses good selectivity, ultralow background, and high sensitivity with a detection limit of 83.28 aM. This method can accurately detect even a 0.001% 5hmU level in the mixture. Moreover, it can determine 5hmU at single-cell level and distinguish the expressions of 5hmU in tissues of normal persons and breast cancer patients, holding great promise in 5hmU-related biological research and clinical diagnosis.


Subject(s)
DNA , Pentoxyl , Humans , DNA/metabolism , Pentoxyl/metabolism , Cell Line
9.
Gut ; 73(1): 63-77, 2023 Dec 07.
Article in English | MEDLINE | ID: mdl-36977555

ABSTRACT

OBJECTIVE: Early gastric cardia adenocarcinoma (EGCA) is a highly heterogeneous cancer, and the understanding of its classification and malignant progression is limited. This study explored the cellular and molecular heterogeneity in EGCA using single-cell RNA sequencing (scRNA-seq). DESIGN: scRNA-seq was conducted on 95 551 cells from endoscopic biopsies of low-grade intraepithelial neoplasia, well/moderately/poorly differentiated EGCA and their paired adjacent nonmalignant biopsy samples. Large-scale clinical samples and functional experiments were employed. RESULTS: Integrative analysis of epithelial cells revealed that chief cells, parietal cells and enteroendocrine cells were rarely detected in the malignant epithelial subpopulation, whereas gland and pit mucous cells and AQP5+ stem cells were predominant during malignant progression. Pseudotime and functional enrichment analyses showed that the WNT and NF-κB signalling pathways were activated during the transition. Cluster analysis of heterogeneous malignant cells revealed that NNMT-mediated nicotinamide metabolism was enriched in gastric mucin phenotype cell population, which was associated with tumour initiation and inflammation-induced angiogenesis. Furthermore, the expression level of NNMT was gradually increased during the malignant progression and associated with poor prognosis in cardia adenocarcinoma. Mechanistically, NNMT catalysed the conversion of nicotinamide to 1-methyl nicotinamide via depleting S-adenosyl methionine, which led to a reduction in H3K27 trimethylation (H3K27me3) and then activated the WNT signalling pathway to maintain the stemness of AQP5+ stem cells during EGCA malignant progression. CONCLUSION: Our study extends the understanding of the heterogeneity of EGCA and identifies a functional NNMT+/AQP5+ population that may drive malignant progression in EGCA and could be used for early diagnosis and therapy.


Subject(s)
Adenocarcinoma , Stomach Neoplasms , Humans , Cardia/metabolism , S-Adenosylmethionine , Neoplastic Stem Cells/metabolism , Niacinamide , Nicotinamide N-Methyltransferase/genetics , Nicotinamide N-Methyltransferase/metabolism , Aquaporin 5
10.
J Cell Mol Med ; 27(3): 422-434, 2023 02.
Article in English | MEDLINE | ID: mdl-36651446

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive interstitial lung disease that seriously threatens the health of patients. The pathogenesis of IPF is still unclear, and there is a lack of effective therapeutic drugs. Myofibroblasts are the main effector cells of IPF, leading to excessive deposition of extracellular matrix (ECM) and promoting the progression of fibrosis. Inhibiting the excessive activation and relieving autophagy blockage of myofibroblasts is the key to treat IPF. PI3K/Akt/mTOR pathway plays a key regulatory role in promoting fibroblast activation and autophagy inhibition in lung fibrosis. Duvelisib is a PI3K inhibitor that can simultaneously inhibit the activities of PI3K-δ and PI3K-γ, and is mainly used for the treatment of relapsed/refractory chronic lymphocytic leukaemia (CLL) and small lymphocytic lymphoma tumour (SLL). In this study, we aimed to examine the effects of Duvelisib on pulmonary fibrosis. We used a mouse model of bleomycin-induced pulmonary fibrosis to evaluate the effects of Duvelisib on pulmonary fibrosis in vivo and further explored the potential pharmacological mechanisms of Duvelisib in lung fibroblasts in vitro. The in vivo experiments showed that Duvelisib significantly alleviated bleomycin-induced collagen deposition and improved pulmonary function. In vitro and in vivo pharmacological experiments showed that Duvelisib dose-dependently suppressed lung fibroblast activation and improved autophagy inhibition by inhibiting the phosphorylation of PI3K, Akt and mTOR. Our results indicate that Duvelisib can alleviate the severity of pulmonary fibrosis and provide potential drugs for the treatment of pulmonary fibrosis.


Subject(s)
Idiopathic Pulmonary Fibrosis , Proto-Oncogene Proteins c-akt , Animals , Mice , Bleomycin/toxicity , Fibroblasts/metabolism , Idiopathic Pulmonary Fibrosis/metabolism , Lung/pathology , Neoplasm Recurrence, Local/pathology , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , TOR Serine-Threonine Kinases/metabolism
11.
Metab Eng ; 77: 12-20, 2023 05.
Article in English | MEDLINE | ID: mdl-36889504

ABSTRACT

Food wastes can be hydrolyzed into soluble microbial substrates, contributing to sustainability. Halomonas spp.-based Next Generation Industrial Biotechnology (NGIB) allows open, unsterile fermentation, eliminating the need for sterilization to avoid the Maillard reaction that negatively affects cell growth. This is especially important for food waste hydrolysates, which have a high nutrient content but are unstable due to batch, sources, or storage conditions. These make them unsuitable for polyhydroxyalkanoate (PHA) production, which usually requires limitation on either nitrogen, phosphorous, or sulfur. In this study, H. bluephagenesis was constructed by overexpressing the PHA synthesis operon phaCABCn (cloned from Cupriavidus necator) controlled by the essential gene ompW (encoding outer membrane protein W) promoter and the constitutive porin promoter that are continuously expressed at high levels throughout the cell growth process, allowing poly(3-hydroxybutyrate) (PHB) production to proceed in nutrient-rich (also nitrogen-rich) food waste hydrolysates of various sources. The recombinant H. bluephagenesis termed WZY278 generated 22 g L-1 cell dry weight (CDW) containing 80 wt% PHB when cultured in food waste hydrolysates in shake flasks, and it was grown to 70 g L-1 CDW containing 80 wt% PHB in a 7-L bioreactor via fed-batch cultivation. Thus, unsterilizable food waste hydrolysates can become nutrient-rich substrates for PHB production by H. bluephagenesis able to be grown contamination-free under open conditions.


Subject(s)
Halomonas , Polyhydroxyalkanoates , Refuse Disposal , Polyesters/metabolism , Halomonas/metabolism , Food , Genes, Essential , Polyhydroxyalkanoates/genetics , Polyhydroxyalkanoates/metabolism , Hydroxybutyrates/metabolism
12.
Diabetes Obes Metab ; 25(7): 1964-1972, 2023 07.
Article in English | MEDLINE | ID: mdl-36974352

ABSTRACT

AIM: This study compared the pharmacokinetics, glucodynamics and tolerability following single subcutaneous doses of ultra rapid lispro (URLi) versus Humalog in children (6-11 years), adolescents (12-17 years) and adults (18-64 years) with type 1 diabetes mellitus (T1D). MATERIALS AND METHODS: The study was a randomized, two-period, subject- and investigator-blind, crossover design in participants with T1D. Participants received a 0.2 U/kg bolus dose immediately before a liquid mixed meal tolerance test. Insulin lispro and glucose concentrations were measured. RESULTS: The study included 13 children, 14 adolescents and 15 adults. Consistently across the age groups, onset of appearance was 4-5 min faster, the early 50% tmax was reduced by 7-13 min, and exposure in the first 15 min was increased by 3.5-6.5-fold following URLi compared with Humalog (all p < .01). Exposure after 3 h was decreased by 37-58% (p = .02) and the duration was reduced by 56 min (p = .006) in children and 36 min (p = .022) in adolescents with URLi compared with Humalog. The maximum and overall exposure were similar between treatments. Postprandial glucose at 1 h was reduced by 42 mg/dl in children (p = .008), 19 mg/dl (p = .195) in adolescents and 34 mg/dl (p = .018) in adults following URLi versus Humalog. The glucose excursion during a 5-h test meal period was reduced by 16% in children and 9% in adolescents compared with Humalog. URLi was well tolerated in all age groups. CONCLUSIONS: URLi showed an accelerated insulin lispro absorption and greater postprandial glucose reduction compared with Humalog in children, adolescents and adults with T1D.


Subject(s)
Diabetes Mellitus, Type 1 , Adult , Adolescent , Child , Humans , Insulin Lispro/therapeutic use , Insulin Lispro/pharmacokinetics , Diabetes Mellitus, Type 1/drug therapy , Hypoglycemic Agents/adverse effects , Glucose/therapeutic use , Blood Glucose , Postprandial Period , Cross-Over Studies , Insulin
13.
Molecules ; 28(16)2023 Aug 12.
Article in English | MEDLINE | ID: mdl-37630287

ABSTRACT

(1) Background: Heart failure (HF) is the final stage of multiple cardiac diseases, which have now become a severe public health problem worldwide. ß-Adrenergic receptor (ß-AR) overactivation is a major pathological factor associated with multiple cardiac diseases and mediates cardiac fibrosis and inflammation. Previous research has demonstrated that Bruton's tyrosine kinase (BTK) mediated cardiac fibrosis by TGF-ß related signal pathways, indicating that BTK was a potential drug target for cardiac fibrosis. Zanubrutinib, a second-generation BTK inhibitor, has shown anti-fibrosis effects in previous research. However, it is unclear whether Zanubrutinib can alleviate cardiac fibrosis induced by ß-AR overactivation; (2) Methods: In vivo: Male C57BL/6J mice were treated with or without the ß-AR agonist isoproterenol (ISO) to establish a cardiac fibrosis animal model; (3) Results: In vivo: Results showed that the BTK inhibitor Zanubrutinib (ZB) had a great effect on cardiac fibrosis and inflammation induced by ß-AR. In vitro: Results showed that ZB alleviated ß-AR-induced cardiac fibroblast activation and macrophage pro-inflammatory cytokine production. Further mechanism studies demonstrated that ZB inhibited ß-AR-induced cardiac fibrosis and inflammation by the BTK, STAT3, NF-κB, and PI3K/Akt signal pathways both in vivo and in vitro; (4) Conclusions: our research provides evidence that ZB ameliorates ß-AR-induced cardiac fibrosis and inflammation.


Subject(s)
Heart Diseases , Phosphatidylinositol 3-Kinases , Male , Mice , Animals , Mice, Inbred C57BL , Inflammation/drug therapy , Agammaglobulinaemia Tyrosine Kinase
14.
Biochemistry ; 61(19): 2118-2130, 2022 10 04.
Article in English | MEDLINE | ID: mdl-36094889

ABSTRACT

Class II lanthipeptide synthetases (LanM enzymes) catalyze the installation of multiple thioether bridges into genetically encoded peptides to produce macrocyclic lanthipeptides, a class of biologically active natural products. Collectively, LanM enzymes install thioether rings of different sizes, topologies, and stereochemistry into a vast array of different LanA precursor peptide sequences. The factors that govern the outcome of the LanM-catalyzed reaction cascade are not fully characterized but are thought to involve both intermolecular interactions and intramolecular conformational changes in the [LanM:LanA] Michaelis complex. To test this hypothesis, we have combined AlphaFold modeling with hydrogen-deuterium exchange mass spectrometry (HDX-MS) analysis of a small collection of divergent LanM/LanA systems to investigate the similarities and differences in their conformational dynamic properties. Our data indicate that LanA precursor peptide binding triggers relatively conserved changes in the structural dynamics of the LanM dehydratase domain, supporting the existence of a similar leader peptide binding mode across the LanM family. In contrast, changes induced in the dynamics of the LanM cyclase domain were more highly variable between enzymes, perhaps reflecting different peptide-cyclase interactions and/or different modes of allosteric activation in class II lanthipeptide biosynthesis. Our analysis highlights the ability of the emerging AlphaFold platform to predict protein-peptide interactions that are supported by other lines of experimental evidence. The combination of AlphaFold modeling with HDX-MS analysis should emerge as a useful approach for investigating other conformationally dynamic enzymes involved in peptide natural product biosynthesis.


Subject(s)
Biological Products , Hydrogen Deuterium Exchange-Mass Spectrometry , Deuterium , Deuterium Exchange Measurement , Hydro-Lyases/metabolism , Ligases/metabolism , Peptides/chemistry , Protein Sorting Signals , Sulfides
16.
Virol J ; 19(1): 201, 2022 11 29.
Article in English | MEDLINE | ID: mdl-36447230

ABSTRACT

BACKGROUND: Classical swine fever (CSF), African swine fever (ASF), and atypical porcine pestivirus (APPV) are acute, virulent, and contagious viral diseases currently hampering the pig industry in China, which result in mummification or stillbirths in piglets and mortality in pigs. Diagnostic assays for the differentiation of infection and vaccination of CSFV, in addition to the detection of ASFV and APPV, are urgently required for better prevention, control, and elimination of these viral diseases in China. METHODS: A quadruple PCR-based gene microarray assay was developed in this study to simultaneously detect wild-type and vaccine CSFV strains, ASFV and APPV according to their conserved regions. Forty-two laboratory-confirmed samples, including positive samples of 10 other swine viral diseases, were tested using this assay to confirm its high specificity. RESULTS: This assay's limit of detections (LODs) for the wild-type and vaccine CSFV were 6.98 and 6.92 copies/µL. LODs for ASFV and APPV were 2.56 × 10 and 1.80 × 10 copies/µL, respectively. When compared with standard RT-PCR or qPCR for CSFV (GB/T 26875-2018), ASFV (MARR issue No.172), or APPV (CN108611442A) using 219 clinical samples, the coincidence was 100%. The results showed that this assay with high sensitivity could specifically distinguish ASFV, APPV, and CSFV, including CSFV infection and immunization. CONCLUSION: This assay provides a practical, simple, economic, and reliable test for the rapid detection and accurate diagnosis of the three viruses and may have good prospects for application in an epidemiological investigation, prevention, and control and elimination of these three diseases.


Subject(s)
African Swine Fever Virus , African Swine Fever , Classical Swine Fever Virus , Pestivirus , Swine Diseases , Vaccines , Animals , Swine , Classical Swine Fever Virus/genetics , Pestivirus/genetics , Real-Time Polymerase Chain Reaction , Swine Diseases/diagnosis , Swine Diseases/prevention & control
17.
Biomacromolecules ; 23(12): 5007-5017, 2022 Dec 12.
Article in English | MEDLINE | ID: mdl-36379034

ABSTRACT

The surgical treatments of injured soft tissues lead to further injury due to the use of sutures or the surgical routes, which need to be large enough to insert biomaterials for repair. In contrast, the use of low viscosity photopolymerizable hydrogels that can be inserted with thin needles represents a less traumatic treatment and would therefore reduce the severity of iatrogenic injury. However, the delivery of light to solidify the inserted hydrogel precursor requires a direct access to it, which is mostly invasive. To circumvent this limitation, we investigate the approach of curing the hydrogel located behind biological tissues by sending near-infrared (NIR) light through the latter, as this spectral region has the largest transmittance in biological tissues. Upconverting nanoparticles (UCNPs) are incorporated in the hydrogel precursor to convert NIR transmitted through the tissues into blue light to trigger the photopolymerization. We investigated the photopolymerization process of an adhesive hydrogel placed behind a soft tissue. Bulk polymerization was achieved with local radiation of the adhesive hydrogel through a focused light system. Thus, unlike the common methods for uniform illumination, adhesion formation was achieved with local micrometer-sized radiation of the bulky hydrogel through a gradient photopolymerization phenomenon. Nanoindentation and upright microscope analysis confirmed that the proposed approach for indirect curing of hydrogels below the tissue is a gradient photopolymerization phenomenon. Moreover, we found that the hydrogel mechanical and adhesive properties can be modulated by playing with different parameters of the system such as the NIR light power and the UCNP concentration. The proposed photopolymerization of adhesive hydrogels below the tissue opens the prospect of a minimally invasive surgical treatment of injured soft tissues.


Subject(s)
Hydrogels , Nanoparticles , Adhesives , Biocompatible Materials , Polymerization
18.
Int J Mol Sci ; 23(8)2022 Apr 08.
Article in English | MEDLINE | ID: mdl-35456964

ABSTRACT

TRPV4 (transient receptor potential vanilloid 4), a calcium permeable TRP ion channel, is known to play a key role in endocytosis. However, whether it contributes to exocytosis remains unclear. Here, we report that activation of TRPV4 induced massive exocytosis in both melanoma A375 cell and heterologous expression systems. We show here that, upon application of TRPV4-specific agonists, prominent vesicle priming from endoplasmic reticulum (ER) was observed, followed by morphological changes of mitochondrial crista may lead to cell ferroptosis. We further identified interactions between TRPV4 and folding/vesicle trafficking proteins, which were triggered by calcium entry through activated TRPV4. This interplay, in turn, enhanced TRPV4-mediated activation of folding and vesicle trafficking proteins to promote exocytosis. Our study revealed a signaling mechanism underlying stimulus-triggered exocytosis in melanoma and highlighted the role of cellular sensor TRPV4 ion channel in mediating ferroptosis.


Subject(s)
Ferroptosis , Melanoma , Calcium/metabolism , Calcium Channels , Exocytosis/physiology , Humans , TRPV Cation Channels/metabolism
19.
Ecotoxicol Environ Saf ; 228: 112938, 2021 Nov 03.
Article in English | MEDLINE | ID: mdl-34741930

ABSTRACT

Inhaling silica dust in the environment can cause progressive pulmonary fibrosis, then silicosis. Silicosis is the most harmful occupational disease in the world, so the study of the mechanism is of great significance for the prevention and treatment of silicosis. Long non-coding RNAs (lncRNAs) are important players in the pathological process of fibrotic diseases. However, the function of specific lncRNA in regulating pulmonary fibrosis remains elusive. In this study, a mouse model of pulmonary fibrosis via intratracheal instillation of silica particles was established, and the differential expression of lnc-SNHG1 and miR-326 in lung tissues and TGF-ß1-treated fibroblasts was detected by the qRT-PCR method. Short interfering RNA (siRNA) and plasmid were designed for knockdown or overexpression of lnc-SNHG1 in fibroblasts. MiRNA simulant was designed for overexpression of miR-326 in vivo and in vitro. Dual-luciferase reporter system, immunofluorescence, western blot, wound healing and transwell assay were performed to investigate the function and the underlying mechanisms of lnc-SNHG1. As a result, we found that lnc-SNHG1 was highly expressed in fibrotic lung tissues of mice and TGF-ß1-treated fibroblasts. Moreover, the high expression of lnc-SNHG1 facilitated the migration and invasion of fibroblasts and the secretion of fibrotic molecules, while the low expression of lnc-SNHG1 exerted the opposite effects. Further mechanism studies showed that miR-326 was the potential target of lnc-SNHG1, and there is a negative correlation between the expression levels of lnc-SNHG1 and miR-326. Combined with mitigating fibrotic effects of miR-326 in a mouse model of silica particles exposure, we revealed that lnc-SNHG1 significantly sponged miR-326 and facilitated the expression of SP1, thus accelerating fibroblast-to-myofibroblast transition and synergistically promoting the development of pulmonary fibrosis. Our study uncovered a key mechanism by which lnc-SNHG1 regulated pulmonary fibrosis through miR-326/SP1 axis, and lnc-SNHG1 is a potential target for the prevention and treatment of silicosis.

20.
Int J Mol Sci ; 22(3)2021 Jan 20.
Article in English | MEDLINE | ID: mdl-33498409

ABSTRACT

Diabetic retinopathy (DR), one of the leading causes of blindness, is mainly diagnosed based on the vascular pathology of the disease. Current treatment options largely focus on this aspect with mostly insufficient therapeutic long-term efficacy. Mounting evidence implicates mitochondrial dysfunction and oxidative stress in the central etiology of DR. Consequently, drug candidates that aim at normalizing mitochondrial function could be an attractive therapeutic approach. This study compared the mitoprotective compounds, idebenone and elamipretide, side-by-side against two novel short-chain quinones (SCQs) in a rat model of DR. The model effectively mimicked type 2 diabetes over 21 weeks. During this period, visual acuity was monitored by measuring optokinetic response (OKR). Vision loss occurred 5-8 weeks after the onset of hyperglycemia. After 10 weeks of hyperglycemia, visual function was reduced by 65%. From this point, the right eyes of the animals were topically treated once daily with the test compounds. The left, untreated eye served as an internal control. Only three weeks of topical treatment significantly restored vision from 35% to 58-80%, while visual acuity of the non-treated eyes continued to deteriorate. Interestingly, the two novel SCQs restored visual acuity better than idebenone or elamipretide. This was also reflected by protection of retinal pathology against oxidative damage, retinal ganglion cell loss, reactive gliosis, vascular leakage, and retinal thinning. Overall, mitoprotective and, in particular, SCQ-based compounds have the potential to be developed into effective and fast-acting drug candidates against DR.


Subject(s)
Antioxidants/therapeutic use , Diabetic Retinopathy/drug therapy , Ubiquinone/analogs & derivatives , Animals , Antioxidants/pharmacology , Male , Mitochondria/drug effects , Oligopeptides/pharmacology , Oligopeptides/therapeutic use , Rats , Rats, Long-Evans , Ubiquinone/pharmacology , Ubiquinone/therapeutic use , Vision, Ocular
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