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1.
Biochim Biophys Acta Mol Basis Dis ; 1870(7): 167435, 2024 10.
Article in English | MEDLINE | ID: mdl-39067535

ABSTRACT

INTRODUCTION: Microglia play pivotal roles in post-intracerebral hemorrhage (ICH) neural injury. Iron metabolism, which is dysregulated after ICH, participates in microglial dysfunction. Previous studies have shown that iron metabolism-related lipocalin-2 (LCN2) is involved in regulating microglial function following ICH. In this study, we investigated the role of LCN2 in microglial function following ICH. METHODS: The BV2 (microglia) cell line, transfected with LCN2 for overexpression/interference, received a blood infusion from C57BL/6 mice in vitro. For the in vivo study of LCN2 function, an LCN2 knockout was conducted in mice. Liproxstatin-1 and RSL3 were used to manipulate ferroptosis and to study the effects of LCN2 on microglia after ICH. A BV2 (microglia) cell line, transfected with ferritin light chain (FTL) for overexpression/interference, was co-cultured with primary cultured neurons for a study on the mechanism of LCN2. Behavioral tests were conducted pre-ICH and on days 3, 7, and 28 post-ICH, and the brains and cultured cells were collected for protein, histological, and morphological studies. RESULTS: Brain LCN2 expression was upregulated in microglia, astrocytes, and neurons and played hazardous roles after ICH. In microglia, LCN2 promoted ferroptosis, which facilitated neural injury after ICH. LCN2-mediated FTL deficiency was shown to be responsible for microglial ferroptosis-induced neural injury. CONCLUSION: Our study suggests that LCN2-enhanced microglial ferroptosis plays a detrimental role by inducing FTL deficiency after ICH. The current study reveals a novel molecular mechanism involved in the pathophysiological progression of ICH.


Subject(s)
Cerebral Hemorrhage , Ferroptosis , Lipocalin-2 , Mice, Knockout , Microglia , Animals , Lipocalin-2/metabolism , Lipocalin-2/genetics , Microglia/metabolism , Microglia/pathology , Microglia/drug effects , Cerebral Hemorrhage/metabolism , Cerebral Hemorrhage/pathology , Cerebral Hemorrhage/genetics , Ferroptosis/drug effects , Mice , Male , Mice, Inbred C57BL , Neurons/metabolism , Neurons/pathology , Neurons/drug effects , Apoferritins/metabolism , Apoferritins/genetics , Disease Models, Animal , Cell Line
2.
Front Med ; 18(4): 708-720, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38833102

ABSTRACT

CD39 serves as a crucial biomarker for neoantigen-specific CD8+ T cells and is associated with antitumor activity and exhaustion. However, the relationship between CD39 expression levels and the function of chimeric antigen receptor T (CAR-T) cells remains controversial. This study aimed to investigate the role of CD39 in the functional performance of CAR-T cells against hepatocellular carcinoma (HCC) and explore the therapeutic potential of CD39 modulators, such as mitochondrial division inhibitor-1 (mdivi-1), or knockdown CD39 through short hairpin RNA. Our findings demonstrated that glypican-3-CAR-T cells with moderate CD39 expression exhibited a strong antitumor activity, while high and low levels of CD39 led to an impaired cellular function. Methods modulating the proportion of CD39 intermediate (CD39int)-phenotype CAR-T cells such as mdivi-1 and CD39 knockdown enhanced and impaired T cell function, respectively. The combination of mdivi-1 and CD39 knockdown in CAR-T cells yielded the highest proportion of infiltrated CD39int CAR-T cells and demonstrated a robust antitumor activity in vivo. In conclusion, this study revealed the crucial role of CD39 in CAR-T cell function, demonstrated the potential therapeutic efficacy of combining mdivi-1 with CD39 knockdown in HCC, and provided a novel treatment strategy for HCC patients in the field of cellular immunotherapy.


Subject(s)
Apyrase , Carcinoma, Hepatocellular , Glypicans , Immunotherapy, Adoptive , Liver Neoplasms , Receptors, Chimeric Antigen , Carcinoma, Hepatocellular/immunology , Carcinoma, Hepatocellular/therapy , Carcinoma, Hepatocellular/genetics , Glypicans/immunology , Glypicans/genetics , Glypicans/metabolism , Liver Neoplasms/immunology , Liver Neoplasms/therapy , Liver Neoplasms/genetics , Apyrase/metabolism , Apyrase/genetics , Humans , Animals , Mice , Immunotherapy, Adoptive/methods , Receptors, Chimeric Antigen/immunology , Receptors, Chimeric Antigen/genetics , Cell Line, Tumor , Antigens, CD/genetics , Antigens, CD/metabolism , Xenograft Model Antitumor Assays
3.
Nat Commun ; 15(1): 4859, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38849339

ABSTRACT

One-dimensional (1D) olivine iron phosphate (FePO4) is widely proposed for electrochemical lithium (Li) extraction from dilute water sources, however, significant variations in Li selectivity were observed for particles with different physical attributes. Understanding how particle features influence Li and sodium (Na) co-intercalation is crucial for system design and enhancing Li selectivity. Here, we investigate a series of FePO4 particles with various features and revealed the importance of harnessing kinetic and chemo-mechanical barrier difference between lithiation and sodiation to promote selectivity. The thermodynamic preference of FePO4 provides baseline of selectivity while the particle features are critical to induce different kinetic pathways and barriers, resulting in different Li to Na selectivity from 6.2 × 102 to 2.3 × 104. Importantly, we categorize the FePO4 particles into two groups based on their distinctly paired phase evolutions upon lithiation and sodiation, and generate quantitative correlation maps among Li preference, morphological features, and electrochemical properties. By selecting FePO4 particles with specific features, we demonstrate fast (636 mA/g) Li extraction from a high Li source (1: 100 Li to Na) with (96.6 ± 0.2)% purity, and high selectivity (2.3 × 104) from a low Li source (1: 1000 Li to Na) with (95.8 ± 0.3)% purity in a single step.

5.
J Neuroinflammation ; 21(1): 85, 2024 Apr 06.
Article in English | MEDLINE | ID: mdl-38582897

ABSTRACT

Homer1a and A2 astrocytes are involved in the regulation of inflammation induced by intracerebral hemorrhage (ICH). However, there is no anticipated treatment strategy based on the anti-inflammatory effect of Homer1a and A2 astrocytes. Here, we successfully induced A2 astrocytes in vitro, and then we report an efficient method to prepare Homer1a+ EVs derived from A2 astrocytes which making it more stable, safe, and targetable to injured neurons. Homer1a+ EVs promotes the conversion of A1 to A2 astrocytes in ICH mice. Homer1a+ EVs inhibits activation and nuclear translocation of NF-κB, thereby regulating transcription of IL-17A in neurons. Homer1a+ EVs inhibits the RAGE/NF-κB/IL-17 signaling pathway and the binding ability of IL-17A: IL17-AR and RAGE: DIAPH1. In addition, Homer1a+ EVs ameliorates the pathology, behavior, and survival rate in GFAPCreHomer1fl/-Homer1a± and NestinCreRAGEfl/fl ICH mice. Our study provides a novel insight and potential for the clinical translation of Homer1a+ EVs in the treatment of ICH.


Subject(s)
Extracellular Vesicles , NF-kappa B , Mice , Animals , NF-kappa B/metabolism , Interleukin-17 , Cerebral Hemorrhage/metabolism , Signal Transduction , Extracellular Vesicles/metabolism
6.
Acta Pharm Sin B ; 14(3): 1030-1076, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38487004

ABSTRACT

Synthetic chemistry plays an indispensable role in drug discovery, contributing to hit compounds identification, lead compounds optimization, candidate drugs preparation, and so on. As Nobel Prize laureate James Black emphasized, "the most fruitful basis for the discovery of a new drug is to start with an old drug"1. Late-stage modification or functionalization of drugs, natural products and bioactive compounds have garnered significant interest due to its ability to introduce diverse elements into bioactive compounds promptly. Such modifications alter the chemical space and physiochemical properties of these compounds, ultimately influencing their potency and druggability. To enrich a toolbox of chemical modification methods for drug discovery, this review focuses on the incorporation of halogen, oxygen, and nitrogen-the ubiquitous elements in pharmacophore components of the marketed drugs-through late-stage modification in recent two decades, and discusses the state and challenges faced in these fields. We also emphasize that increasing cooperation between chemists and pharmacists may be conducive to the rapid discovery of new activities of the functionalized molecules. Ultimately, we hope this review would serve as a valuable resource, facilitating the application of late-stage modification in the construction of novel molecules and inspiring innovative concepts for designing and building new drugs.

7.
Nat Commun ; 15(1): 1886, 2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38424055

ABSTRACT

The photochemical properties of Electron Donor-Acceptor (EDA) complexes present exciting opportunities for synthetic chemistry. However, these strategies often require an inert atmosphere to maintain high efficiency. Herein, we develop an EDA complex photocatalytic system through rational design, which overcomes the oxygen-sensitive limitation of traditional EDA photocatalytic systems and enables aerobic oxygenation reactions through dioxygen activation. The mild oxidation system transfers electrons from the donor to the effective catalytic acceptor upon visible light irradiation, which are subsequently captured by molecular oxygen to form the superoxide radical ion, as demonstrated by the specific fluorescent probe, dihydroethidine (DHE). Furthermore, this visible-light mediated oxidative EDA protocol is successfully applied in the aerobic oxygenation of boronic acids. We believe that this photochemical dioxygen activation strategy enabled by EDA complex not only provides a practical approach to aerobic oxygenation but also promotes the design and application of EDA photocatalysis under ambient conditions.

8.
Innovation (Camb) ; 5(2): 100586, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38414518

ABSTRACT

The chemical recycling of polyolefin presents a considerable challenge, especially as upcycling methods struggle with the reality that plastic wastes typically consist of mixtures of polyethylene (PE), polystyrene (PS), and polypropylene (PP). We report a catalytic aerobic oxidative approach for polyolefins upcycling with the corresponding carboxylic acids as the product. This method encompasses three key innovations. First, it operates under atmospheric pressure and mild conditions, using O2 or air as the oxidant. Second, it is compatible with high-density polyethylene, low-density polyethylene, PS, PP, and their blends. Third, it uses an economical and recoverable metal catalyst. It has been demonstrated that this approach can efficiently degrade mixed wastes of plastic bags, bottles, masks, and foam boxes.

10.
ACS Sens ; 9(1): 236-243, 2024 01 26.
Article in English | MEDLINE | ID: mdl-38123468

ABSTRACT

Organic molecules are of great interest for gas sensing applications. However, achieving high-performance gas sensors with high sensitivity, fast response, low consumption, and workability in humid conditions is still challenging. Herein, we report the rational design and synthesis of an ion-in-conjugation polymer, PADC (poly-4,4'-azodianiline-croconamide), obtained by the condensation of croconic acid with 4-4'diaminoazobenzene for gas sensing under humid conditions. The as-fabricated PADC-based gas sensor exhibits ultrahigh sensitivity (802.7 ppm-1 at 1 ppm), subppb detection limit, and high selectivity under humid air with an 80% humidity effect at a temperature down to 350 K. PADC shows good planarity, excellent thermostability, and a narrow band gap of 1.2 eV because of azobenzene fragments spacing previously repulsed biphenyl rings. Compared to previous humidity immunity works, PADC-based sensors realized humidity immunity at a relatively lower temperature, resulting in lower energy consumption.


Subject(s)
Nitrogen Dioxide , Poly A , Humidity , Polymers , Temperature
11.
Nanomicro Lett ; 16(1): 29, 2023 Nov 23.
Article in English | MEDLINE | ID: mdl-37994956

ABSTRACT

The laminated transition metal disulfides (TMDs), which are well known as typical two-dimensional (2D) semiconductive materials, possess a unique layered structure, leading to their wide-spread applications in various fields, such as catalysis, energy storage, sensing, etc. In recent years, a lot of research work on TMDs based functional materials in the fields of electromagnetic wave absorption (EMA) has been carried out. Therefore, it is of great significance to elaborate the influence of TMDs on EMA in time to speed up the application. In this review, recent advances in the development of electromagnetic wave (EMW) absorbers based on TMDs, ranging from the VIB group to the VB group are summarized. Their compositions, microstructures, electronic properties, and synthesis methods are presented in detail. Particularly, the modulation of structure engineering from the aspects of heterostructures, defects, morphologies and phases are systematically summarized, focusing on optimizing impedance matching and increasing dielectric and magnetic losses in the EMA materials with tunable EMW absorption performance. Milestones as well as the challenges are also identified to guide the design of new TMDs based dielectric EMA materials with high performance.

12.
Chem Rev ; 123(22): 12313-12370, 2023 Nov 22.
Article in English | MEDLINE | ID: mdl-37942891

ABSTRACT

Late-stage functionalization (LSF) introduces functional group or structural modification at the final stage of the synthesis of natural products, drugs, and complex compounds. It is anticipated that late-stage functionalization would improve drug discovery's effectiveness and efficiency and hasten the creation of various chemical libraries. Consequently, late-stage functionalization of natural products is a productive technique to produce natural product derivatives, which significantly impacts chemical biology and drug development. Carbon-carbon bonds make up the fundamental framework of organic molecules. Compared with the carbon-carbon bond construction, the carbon-carbon bond activation can directly enable molecular editing (deletion, insertion, or modification of atoms or groups of atoms) and provide a more efficient and accurate synthetic strategy. However, the efficient and selective activation of unstrained carbon-carbon bonds is still one of the most challenging projects in organic synthesis. This review encompasses the strategies employed in recent years for carbon-carbon bond cleavage by explicitly focusing on their applicability in late-stage functionalization. This review expands the current discourse on carbon-carbon bond cleavage in late-stage functionalization reactions by providing a comprehensive overview of the selective cleavage of various types of carbon-carbon bonds. This includes C-C(sp), C-C(sp2), and C-C(sp3) single bonds; carbon-carbon double bonds; and carbon-carbon triple bonds, with a focus on catalysis by transition metals or organocatalysts. Additionally, specific topics, such as ring-opening processes involving carbon-carbon bond cleavage in three-, four-, five-, and six-membered rings, are discussed, and exemplar applications of these techniques are showcased in the context of complex bioactive molecules or drug discovery. This review aims to shed light on recent advancements in the field and propose potential avenues for future research in the realm of late-stage carbon-carbon bond functionalization.

13.
Biochim Biophys Acta Mol Cell Res ; 1870(7): 119509, 2023 10.
Article in English | MEDLINE | ID: mdl-37271222

ABSTRACT

Deregulation of lemur tyrosine kinase 2 (LMTK2) is a vital determinant for the onset and progression of malignancies, yet the relationship between LMTK2 and glioblastoma (GBM) is undetermined. This study was carried out to determine the relevance of LMTK2 in GBM. Initiating investigation by assessing The Cancer Genome Atlas (TCGA) data showed LMTK2 mRNA levels were decreased in GBM tissue. Later examination of clinical specimens confirmed low levels of LMTK2 mRNA and protein in GBM tissue. The downregulated level of LMTK2 in patients with GBM was related to poor overall survival. A suppressive function of LMTK2 on the proliferative capability and metastatic potential of GBM cells was demonstrated by overexpressing LMTK2 in GBM cell lines. Moreover, the restoration of LMTK2 augmented the sensitivity of GBM cells to the chemotherapy drug temozolomide. The mechanistic investigation uncovered LMTK2 as a regulator of the runt-related transcription factor 3 (RUNX3)/Notch signaling pathway. The overexpression of LMTK2 increased the expression of RUNX3 while inhibiting the activation of Notch signaling. The silencing of RUNX3 diminished the regulatory role of LMTK2 on Notch signaling. The inhibition of Notch signaling reversed the LMTK2-silencing-elicited protumor effects. Importantly, LMTK2-overexpressed GBM cells displayed weakened tumorigenicity in xenograft models. Our findings illustrate that LMTK2 has a tumor-inhibition function in GBM by constraining Notch signaling via RUNX3. This work indicates the deregulation of the LMTK2-mediated RUNX3/Notch signaling pathway may be a novel molecular mechanism for the malignant transformation of GBMs. This work highlights the interest in LMTK2-related approaches for treating GBM.


Subject(s)
Glioblastoma , Protein-Tyrosine Kinases , Animals , Humans , Cell Line, Tumor , Glioblastoma/metabolism , RNA, Messenger , Receptors, Notch , Protein-Tyrosine Kinases/metabolism
14.
Biomolecules ; 13(5)2023 04 24.
Article in English | MEDLINE | ID: mdl-37238605

ABSTRACT

An NAD+-dependent deacetylase called Sirtuin 3 (Sirt3) is involved in the metabolic processes of the mitochondria, including energy generation, the tricarboxylic acid cycle, and oxidative stress. Sirt3 activation can slow down or prevent mitochondrial dysfunction in response to neurodegenerative disorders, demonstrating a strong neuroprotective impact. The mechanism of Sirt3 in neurodegenerative illnesses has been elucidated over time; it is essential for neuron, astrocyte, and microglial function, and its primary regulatory factors include antiapoptosis, oxidative stress, and the maintenance of metabolic homeostasis. Neurodegenerative disorders, such as Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), amyotrophic lateral sclerosis (ALS), and multiple sclerosis (MS), may benefit from a thorough and in-depth investigation of Sirt3. In this review, we primarily cover Sirt3's role and its regulation in the nerve cells and the connection between Sirt3 and neurodegenerative disorders.


Subject(s)
Neurodegenerative Diseases , Parkinson Disease , Sirtuin 3 , Humans , Central Nervous System/metabolism , Mitochondria/metabolism , Neurodegenerative Diseases/metabolism , Parkinson Disease/metabolism , Sirtuin 3/metabolism
15.
Exp Mol Med ; 55(6): 1203-1217, 2023 06.
Article in English | MEDLINE | ID: mdl-37258577

ABSTRACT

The tripartite motif (TRIM) 22 and mitogen-activated protein kinase (MAPK) signaling pathways play critical roles in the growth of glioblastoma (GBM). However, the molecular mechanism underlying the relationship between TRIM22 and MAPK signaling remains unclear. Here, we found that TRIM22 binds to exon 2 of the sphingosine kinase 2 (SPHK2) gene. An ERK1/2-driven luciferase reporter construct identified TRIM22 as a potential activator of MAPK signaling. Knockout and overexpression of TRIM22 regulate the inhibition and activation of MAPK signaling through the RING-finger domain. TRIM22 binds to Raf-1, a negative regulator of MAPK signaling, and accelerates its degradation by inducing K48-linked ubiquitination, which is related to the CC and SPRY domains of TRIM22 and the C1D domain of Raf-1. In vitro and in vivo, an SPHK2 inhibitor (K145), an ERK1/2 inhibitor (selumetinib), and the nonphosphorylated mutant Raf-1S338A inhibited GBM growth. In addition, deletion of the RING domain and the nuclear localization sequence of TRIM22 significantly inhibited TRIM22-induced proliferation of GBM cells in vivo and in vitro. In conclusion, our study showed that TRIM22 regulates SPHK2 transcription and activates MAPK signaling through posttranslational modification of two critical regulators of MAPK signaling in GBM cells.


Subject(s)
Glioblastoma , Mitogen-Activated Protein Kinases , Humans , Mitogen-Activated Protein Kinases/metabolism , Glioblastoma/genetics , Signal Transduction , Cell Line , Cell Proliferation , Minor Histocompatibility Antigens , Tripartite Motif Proteins/genetics , Tripartite Motif Proteins/metabolism , Repressor Proteins/genetics
16.
Acta Pharm Sin B ; 13(2): 632-647, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36873191

ABSTRACT

Cryoablation (CRA) and microwave ablation (MWA) are two main local treatments for hepatocellular carcinoma (HCC). However, which one is more curative and suitable for combining with immunotherapy is still controversial. Herein, CRA induced higher tumoral PD-L1 expression and more T cells infiltration, but less PD-L1highCD11b+ myeloid cells infiltration than MWA in HCC. Furthermore, CRA had better curative effect than MWA for anti-PD-L1 combination therapy in mouse models. Mechanistically, anti-PD-L1 antibody facilitated infiltration of CD8+ T cells by enhancing the secretion of CXCL9 from cDC1 cells after CRA therapy. On the other hand, anti-PD-L1 antibody promoted the infiltration of NK cells to eliminate PD-L1highCD11b+ myeloid cells by antibody-dependent cell-mediated cytotoxicity (ADCC) effect after CRA therapy. Both aspects relieved the immunosuppressive microenvironment after CRA therapy. Notably, the wild-type PD-L1 Avelumab (Bavencio), compared to the mutant PD-L1 atezolizumab (Tecentriq), was better at inducing the ADCC effect to target PD-L1highCD11b+ myeloid cells. Collectively, our study uncovered the novel insights that CRA showed superior curative effect than MWA in combining with anti-PD-L1 antibody by strengthening CTL/NK cell immune responses, which provided a strong rationale for combining CRA and PD-L1 blockade in the clinical treatment for HCC.

17.
J Hepatol ; 79(1): 126-140, 2023 07.
Article in English | MEDLINE | ID: mdl-36889359

ABSTRACT

BACKGROUND & AIMS: The immune landscape of hepatocellular carcinoma (HCC) following transarterial chemoembolisation (TACE) remains to be clarified. This study aimed to characterise the immune landscape following TACE and the underlying mechanism of HCC progression. METHODS: Tumour samples from five patients with treatment-naive HCC and five patients who received TACE therapy were collected and subjected to single-cell RNA sequencing. Another 22 paired samples were validated using immunofluorescence staining and flow cytometry. To clarify the underlying mechanisms, in vitro co-culture experiments and two types of TREM2-KO/WT mouse models, namely, an HCC cell orthotopic injection model and a spontaneous HCC model, were used. RESULTS: A reduced number of CD8+ T cells and an increased number of tumour-associated macrophages (TAMs) were observed in the post-TACE microenvironment. TACE therapy reduced the cluster CD8_C4, which was highly enriched with tumour-specific CD8+ T cells of pre-exhausted phenotype. TREM2 was found to be highly expressed in TAMs following TACE, which was associated with a poor prognosis. TREM2+ TAMs secreted less CXCL9 but more galectin-1 than did TREM2- TAMs. Galectin-1 promoted PD-L1 overexpression in vessel endothelial cells, impeding CD8+ T cell recruitment. TREM2 deficiency also increased CD8+ T cell infiltration, which inhibited tumour growth in both in vivo HCC models. More importantly, TREM2 deficiency enhanced the therapeutic effect of anti-PD-L1 blockade. CONCLUSIONS: This study shows that TREM2+ TAMs play an important role in suppressing CD8+ T cells. TREM2 deficiency increased the therapeutic effect of anti-PD-L1 blockade by enhancing antitumour activity of CD8+ T cells. These findings explain the reasons for recurrence and progression after TACE and provide a new target for HCC immunotherapy after TACE. IMPACT AND IMPLICATIONS: Studying the immune landscape in post-TACE HCC is important to uncover the mechanisms of HCC progression. By using scRNA sequencing and functional assays, we discovered that both the number and function of CD8+ T cells are compromised, whereas the number of TREM2+ TAMs is increased in post-TACE HCC, correlating with worse prognosis. Moreover, TREM2 deficiency dramatically increases CD8+ T cell infiltration and augments the therapeutic efficacy of anti-PD-L1 blockade. Mechanistically, TREM2+ TAMs display lower CXCL9 and increased Gal-1 secretion than do TREM2- TAMs, with Gal-1 mediating the overexpression of PD-L1 in vessel endothelial cells. These results suggest that TREM2 could be a novel immunotherapeutic target for patients treated with TACE in HCC. This provides an opportunity to break the plateau of limited therapeutic effect. This study has the value of understanding the tumour microenvironment of post-TACE HCC and thinking a new strategy of immunotherapy in the field of HCC. It is therefore of key impact for physicians, scientists and drug developers in the field of liver cancer and gastrointestinal oncology.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Mice , Animals , Carcinoma, Hepatocellular/pathology , Liver Neoplasms/pathology , Galectin 1/therapeutic use , CD8-Positive T-Lymphocytes , Endothelial Cells/pathology , Macrophages , Tumor Microenvironment
18.
Neuroscience ; 514: 67-78, 2023 03 15.
Article in English | MEDLINE | ID: mdl-36738913

ABSTRACT

The pathophysiological process of neuronal injury due to cerebral ischemia is complex among which disturbance of calcium homeostasis and autophagy are two major pathogenesis. However, it remains ambiguous whether the two factors are independent. Stromal interaction molecule 1 (STIM1) is the most important Ca2+ sensor mediating the store-operated Ca2+ entry (SOCE) through interacting with Orai1 and has recently been proven to participate in autophagy in multiple cells. In this study, we aimed to investigate the potential role of STIM1-induced SOCE on autophagy and whether its regulator function contributes to neuronal injury under hypoxic conditions using in vivo transient middle cerebral artery occlusion (tMCAO) model and in vitro oxygen and glucose deprivation (OGD) primary cultured neuron model respectively. The present data indicated that STIM1 induces autophagic flux impairment in neurons through promoting SOCE and inhibiting AKT/mTOR signaling pathway. Pharmacological inhibition of SOCE or downregulation of STIM1 with siRNA suppressed the autophagic activity in neurons. Moreover, stim1 knockdown attenuated neurological deficits and brain damage after tMCAO, which could be reversed by AKT/mTOR pathway inhibitor AZD5363. Together, the modulation of STIM1 on autophagic activation indicated the potential link between Ca2+ homeostasis and autophagy which provided evidence that STIM1 could be a promising therapeutic target for ischemic stroke.


Subject(s)
Calcium , Ischemic Stroke , Autophagy , Calcium/metabolism , Calcium Signaling/physiology , Hippocampus/metabolism , Neurons/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Stromal Interaction Molecule 1/genetics , Stromal Interaction Molecule 1/metabolism , TOR Serine-Threonine Kinases/metabolism , Animals
19.
Biofabrication ; 15(2)2023 03 14.
Article in English | MEDLINE | ID: mdl-36812580

ABSTRACT

Although autologous bone (AB) grafting is considered to be the gold standard for cranioplasty, unresolved problems remain, such as surgical-site infections and bone flap absorption. In this study, an AB scaffold was constructed via three-dimensional (3D) bedside-bioprinting technology and used for cranioplasty. To simulate the skull structure, a polycaprolactone shell was designed as an external lamina, and 3D-printed AB and a bone marrow-derived mesenchymal stem cell (BMSC) hydrogel was used to mimic cancellous bone for bone regeneration. Ourin vitroresults showed that the scaffold exhibited excellent cellular affinity and promoted osteogenic differentiation of BMSCs in both two-dimensional and 3D culture systems. The scaffold was implanted in beagle dog cranial defects for up to 9 months, and the scaffold promoted new bone and osteoid formation. Furtherin vivostudies indicated that transplanted BMSCs differentiated into vascular endothelium, cartilage, and bone tissues, whereas native BMSCs were recruited into the defect. The results of this study provide a method for bedside bioprinting of a cranioplasty scaffold for bone regeneration, which opens up another window for clinical applications of 3D printing in the future.


Subject(s)
Mesenchymal Stem Cells , Osteogenesis , Animals , Dogs , Tissue Scaffolds/chemistry , Bone Regeneration , Cell Differentiation , Skull/surgery , Printing, Three-Dimensional , Tissue Engineering/methods
20.
Cell Signal ; 104: 110594, 2023 04.
Article in English | MEDLINE | ID: mdl-36646297

ABSTRACT

Ferroptosis is a form of iron-dependent programmed cell death discovered in recent years that has been shown to be involved in diverse neurological disorders. Hydrogen sulfide (H2S) is an important signaling molecule with neuroprotective effects, including antioxidation. However, whether the protective mechanism of H2S is related to ferroptosis remains unknown. Therefore, in this study, we focused on the protective mechanisms of sodium hydrosulfide (NaHS, a donor of H2S) against ferroptosis caused by intracerebral hemorrhage (ICH) using a hemin-induced BV2 cell injury model in vitro. Our results indicated that NaHS enhanced cell viability and reduced hemin-induced lactate dehydrogenase (LDH) release. NaHS suppressed ferroptosis after hemin treatment, which was confirmed by attenuated reactive oxygen species (ROS) and lipid peroxidation, maintained iron homeostasis, recovery of the expression of glutathione peroxidase 4 (GPX4) and solute carrier family 7-member 11 (SLC7A11), and increased glutathione (GSH) production. Moreover, we demonstrated that inhibiting ferroptosis improved cell survival and prevented hemin-induced oxidative stress. In addition, NaHS was also able to block ferroptosis inducer RSL3-induced ferroptotic cell death. We also found that NaHS increased cystathionine-ß-synthase (CBS) expression and H2S levels after hemin treatment. Furthermore, NaHS-induced ferroptosis reduction was inhibited by the CBS inhibitor aminooxyacetic acid (AOAA) as well as by CBS small interference RNA (siCBS). In summary, these findings demonstrated that NaHS protects against hemin-induced ferroptosis by reducing lipid peroxidation, inhibiting iron overload, increasing GSH production, and improving GPX4 and SLC7A11 via the CBS/H2S system. The CBS/H2S system may be a promising target for preventing ferroptosis after ICH.


Subject(s)
Ferroptosis , Hydrogen Sulfide , Cystathionine beta-Synthase/metabolism , Glutathione/metabolism , Hemin/pharmacology , Hemin/metabolism , Hydrogen Sulfide/pharmacology , Hydrogen Sulfide/metabolism , Iron , Lipid Peroxidation , Animals , Mice , Cell Line
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