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Journal of Advanced Research Aug 2023Lipid metabolism dysfunction is widely involved in the pathological process of acute ischemic stroke (AIS). The coordination of lipid metabolism between neurons and...
INTRODUCTION
Lipid metabolism dysfunction is widely involved in the pathological process of acute ischemic stroke (AIS). The coordination of lipid metabolism between neurons and astrocytes is of great significance. However, the full scope of lipid dynamic changes and the function of key lipids during AIS remain unknown. Hence, identifying lipid alterations and characterizing their key roles in AIS is of great importance.
METHODS
Untargeted and targeted lipidomic analyses were applied to profile lipid changes in the ischemic penumbra and peripheral blood of transient middle cerebral artery occlusion (tMCAO) mice as well as the peripheral blood of AIS patients. Infarct volume and neurological deficits were assessed after tMCAO. The cell viability and dendritic complexity of primary neurons were evaluated by CCK8 assay and Sholl analysis. Seahorse, MitoTracker Green, tetramethyl rhodamine methyl ester (TMRM), 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) and MitoSOX were used as markers of mitochondrial health. Fluorescent and isotopic free fatty acid (FFA) pulse-chase assays were used to track FFA flux in astrocytes.
RESULTS
Long-chain acylcarnitines (LCACs) were the lipids with the most dramatic changes in the ischemic penumbra and peripheral blood of tMCAO mice. LCACs were significantly elevated on admission in AIS patients and associated with poor outcomes in AIS patients. Increasing LCACs through a bolus administration of palmitoylcarnitine amplified stroke injury, while decreasing LCACs by overexpressing carnitine palmitoyltransferase 2 (CPT2) ameliorated stroke injury. Palmitoylcarnitine aggravated astrocytic mitochondrial damage after OGD/R, while CPT2 overexpression in astrocytes ameliorated cocultured neuron viability. Further study revealed that astrocytes stimulated by OGD/R liberated FFAs from lipid droplets into mitochondria to form LCACs, resulting in mitochondrial damage and lowered astrocytic metabolic support and thereby aggravated neuronal damage.
CONCLUSION
LCACs could accumulate and damage neurons by inducing astrocytic mitochondrial dysfunction in AIS. LCACs play a crucial role in the pathology of AIS and are novel promising diagnostic and prognostic biomarkers for AIS.
PubMed: 37572732
DOI: 10.1016/j.jare.2023.08.007 -
Autophagy Apr 2024Activated transmembrane receptors continue to signal following endocytosis and are only silenced upon ESCRT-mediated internalization of the receptors into intralumenal...
Activated transmembrane receptors continue to signal following endocytosis and are only silenced upon ESCRT-mediated internalization of the receptors into intralumenal vesicles (ILVs) of the endosomes. Accordingly, endosomes with dysfunctional receptor internalization into ILVs can cause sustained receptor signaling which has been implicated in cancer progression. Here, we describe a surveillance mechanism that allows cells to detect and clear physically intact endosomes with aberrant receptor accumulation and elevated signaling. Proximity biotinylation and proteomics analyses of ESCRT-0 defective endosomes revealed a strong enrichment of the ubiquitin-binding macroautophagy/autophagy receptors SQSTM1 and NBR1, a phenotype that was confirmed in cell culture and fly tissue. Live cell microscopy demonstrated that loss of the ESCRT-0 subunit HGS/HRS or the ESCRT-I subunit VPS37 led to high levels of ubiquitinated and phosphorylated receptors on endosomes. This was accompanied by dynamic recruitment of NBR1 and SQSTM1 as well as proteins involved in autophagy initiation and autophagosome biogenesis. Light microscopy and electron tomography revealed that endosomes with intact limiting membrane, but aberrant receptor downregulation were engulfed by phagophores. Inhibition of autophagy caused increased intra- and intercellular signaling and directed cell migration. We conclude that dysfunctional endosomes are surveyed and cleared by an autophagic process, simaphagy, which serves as a failsafe mechanism in signal termination. AKT: AKT serine/threonine kinase; APEX2: apurinic/apyrimidinic endodoexyribonuclease 2; ctrl: control; EEA1: early endosome antigen 1; EGF: epidermal growth factor; EGFR: epidermal growth factor receptor; ESCRT: endosomal sorting complex required for transport; GFP: green fluorescent protein; HGS/HRS: hepatocyte growth factor-regulated tyrosine kinase substrate; IF: immunofluorescence; ILV: intralumenal vesicle; KO: knockout; LIR: LC3-interacting region; LLOMe: L-leucyl-L-leucine methyl ester (hydrochloride); MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MAPK1/ERK2: mitogen-activated protein kinase 1; MAPK3/ERK1: mitogen-activated protein kinase 3; NBR1: NBR1 autophagy cargo receptor; PAG10: Protein A-conjugated 10-nm gold; RB1CC1/FIP200: RB1 inducible coiled-coil 1; siRNA: small interfering RNA; SQSTM1: sequestosome 1; TUB: Tubulin; UBA: ubiquitin-associated; ULK1: unc-51 like autophagy activating kinase 1; VCL: Vinculin; VPS37: VPS37 subunit of ESCRT-I; WB: western blot; WT: wild-type.
Topics: Endosomes; Humans; Endosomal Sorting Complexes Required for Transport; Autophagy; Signal Transduction; Animals; Intracellular Signaling Peptides and Proteins; Sequestosome-1 Protein; Autophagosomes; Endocytosis; HeLa Cells; Cell Movement
PubMed: 37840274
DOI: 10.1080/15548627.2023.2267958 -
Frontiers in Immunology 2023Glucose metabolism, specifically, hexokinase 2 (HK2), has a critical role in rheumatoid arthritis (RA) fibroblast-like synoviocyte (FLS) phenotype. HK2 localizes not...
BACKGROUND
Glucose metabolism, specifically, hexokinase 2 (HK2), has a critical role in rheumatoid arthritis (RA) fibroblast-like synoviocyte (FLS) phenotype. HK2 localizes not only in the cytosol but also in the mitochondria, where it protects mitochondria against stress. We hypothesize that mitochondria-bound HK2 is a key regulator of RA FLS phenotype.
METHODS
HK2 localization was evaluated by confocal microscopy after FLS stimulation. RA FLSs were infected with Green fluorescent protein (GFP), full-length (FL)-HK2, or HK2 lacking its mitochondrial binding motif (HK2ΔN) expressing adenovirus (Ad). RA FLS was also incubated with methyl jasmonate (MJ; 2.5 mM), tofacitinib (1 µM), or methotrexate (1 µM). RA FLS was tested for migration and invasion and gene expression. Gene associations with HK2 expression were identified by examining single-cell RNA sequencing (scRNA-seq) data from murine models of arthritis. Mice were injected with K/BxN serum and given MJ. Ad-FLHK2 or Ad-HK2ΔN was injected into the knee of wild-type mice.
RESULTS
Cobalt chloride (CoCl) and platelet-derived growth factor (PDGF) stimulation induced HK2 mitochondrial translocation. Overexpression of the HK2 mutant and MJ incubation reversed the invasive and migrative phenotype induced by FL-HK2 after PDGF stimulation, and MJ also decreased the expression of C-X-C Motif Chemokine Ligand 1 (CXCL1) and Collagen Type I Alpha 1 Chain (COL1A1). Of interest, tofacitinib but not methotrexate had an effect on HK2 dissociation from the mitochondria. In murine models, MJ treatment significantly decreased arthritis severity, whereas HK2FL was able to induce synovial hypertrophy as opposed to HK2ΔN.
CONCLUSION
Our results suggest that mitochondrial HK2 regulates the aggressive phenotype of RA FLS. New therapeutic approaches to dissociate HK2 from mitochondria offer a safer approach than global glycolysis inhibition.
Topics: Mice; Animals; Synoviocytes; Hexokinase; Arthritis, Rheumatoid; Synovitis; Methotrexate; Fibroblasts
PubMed: 37529037
DOI: 10.3389/fimmu.2023.1103231 -
Neurochemical Research Nov 2023Hot peppers, also called chilli, chilli pepper, or paprika of the plant genus Capsicum (family Solanaceae), are one of the most used vegetables and spices worldwide.... (Review)
Review
Hot peppers, also called chilli, chilli pepper, or paprika of the plant genus Capsicum (family Solanaceae), are one of the most used vegetables and spices worldwide. Capsaicin (8-methyl N-vanillyl-6-noneamide) is the main pungent principle of hot green and red peppers. By acting on the capsaicin receptor or transient receptor potential cation channel vanilloid subfamily member 1 (TRPV1), capsaicin selectively stimulates and in high doses defunctionalizes capsaicin-sensitive chemonociceptors with C and Aδ afferent fibers. This channel, which is involved in a wide range of neuronal processes, is expressed in peripheral and central branches of capsaicin-sensitive nociceptive neurons, sensory ganglia, the spinal cord, and different brain regions in neuronal cell bodies, dendrites, astrocytes, and pericytes. Several experimental and clinical studies provided evidence that capsaicin protected against ischaemic or excitotoxic cerebral neuronal injury and may lower the risk of cerebral stroke. By preventing neuronal death, memory impairment and inhibiting the amyloidogenic process, capsaicin may also be beneficial in neurodegenerative disorders such as Parkinson's or Alzheimer's diseases. Capsaicin given in systemic inflammation/sepsis exerted beneficial antioxidant and anti-inflammatory effects while defunctionalization of capsaicin-sensitive vagal afferents has been demonstrated to increase brain oxidative stress. Capsaicin may act in the periphery via the vagal sensory fibers expressing TRPV1 receptors to reduce immune oxidative and inflammatory signalling to the brain. Capsaicin given in small doses has also been reported to inhibit the experimentally-induced epileptic seizures. The aim of this review is to provide a concise account on the most recent findings related to this topic. We attempted to delineate such mechanisms by which capsaicin exerts its neuronal protective effects. We also aimed to provide the reader with the current knowledge on the mechanism of action of capsaicin on sensory receptors.
Topics: Capsaicin; TRPV Cation Channels; Neuroprotection; Nociceptors; Spinal Cord; Gonadal Steroid Hormones
PubMed: 37493882
DOI: 10.1007/s11064-023-03983-z -
Nature Communications Aug 2023DNA methylation is important for gene expression and alterations in DNA methylation are involved in the development and progression of cancer and other major diseases....
DNA methylation is important for gene expression and alterations in DNA methylation are involved in the development and progression of cancer and other major diseases. Analysis of DNA methylation patterns has until now been dependent on either a chemical or an enzymatic pre-treatment, which are both time consuming procedures and potentially biased due to incomplete treatment. We present a qPCR technology, EpiDirect®, that allows for direct PCR quantification of DNA methylations using untreated DNA. EpiDirect® is based on the ability of Intercalating Nucleic Acids (INA®) to differentiate between methylated and unmethylated cytosines in a special primer design. With this technology, we develop an assay to analyze the methylation status of a region of the MGMT promoter used in treatment selection and prognosis of glioblastoma patients. We compare the assay to two bisulfite-relying, methyl-specific PCR assays in a study involving 42 brain tumor FFPE samples, revealing high sensitivity, specificity, and the clinical utility of the method.
Topics: Polymerase Chain Reaction; DNA; DNA Methylation; Temperature; Oligonucleotides; CpG Islands
PubMed: 37620381
DOI: 10.1038/s41467-023-40873-y -
Molecules (Basel, Switzerland) Mar 2024Benzimidazole fungicides are a class of highly effective, low-toxicity, systemic broad-spectrum fungicides developed in the 1960s and 1970s, based on the fungicidal... (Review)
Review
Benzimidazole fungicides are a class of highly effective, low-toxicity, systemic broad-spectrum fungicides developed in the 1960s and 1970s, based on the fungicidal activity of the benzimidazole ring structure. They exhibit biological activities including anticancer, antibacterial, and antiparasitic effects. Due to their particularly outstanding antibacterial properties, they are widely used in agriculture to prevent and control various plant diseases caused by fungi. The main products of benzimidazole fungicides include benomyl, carbendazim, thiabendazole, albendazole, thiophanate, thiophanate-methyl, fuberidazole, methyl (1-{[(5-cyanopentyl)amino]carbonyl}-1-benzimidazol-2-yl) carbamate, and carbendazim salicylate. This article mainly reviews the physicochemical properties, toxicological properties, disease control efficacy, and pesticide residue and detection technologies of the aforementioned nine benzimidazole fungicides and their main metabolite (2-aminobenzimidazole). On this basis, a brief outlook on the future research directions of benzimidazole fungicides is presented.
Topics: Fungicides, Industrial; Benzimidazoles; Carbamates; Thiophanate; Anti-Bacterial Agents
PubMed: 38542855
DOI: 10.3390/molecules29061218 -
ACS Energy Letters Jul 2023With the advent of nonfullerene acceptors (NFAs), organic photovoltaic (OPV) devices are now achieving high enough power conversion efficiencies (PCEs) for...
With the advent of nonfullerene acceptors (NFAs), organic photovoltaic (OPV) devices are now achieving high enough power conversion efficiencies (PCEs) for commercialization. However, these high performances rely on active layers processed from petroleum-based and toxic solvents, which are undesirable for mass manufacturing. Here, we demonstrate the use of biorenewable 2-methyltetrahydrofuran (2MeTHF) and cyclopentyl methyl ether (CPME) solvents to process donor: NFA-based OPVs with no additional additives in the active layer. Furthermore, to reduce the overall carbon footprint of the manufacturing cycle of the OPVs, we use polymeric donors that require a few synthetic steps for their synthesis, namely, PTQ10 and FO6-T, which are blended with the Y-series NFA Y12. High performance was achieved using 2MeTHF as the processing solvent, reaching PCEs of 14.5% and 11.4% for PTQ10:Y12 and FO6-T:Y12 blends, respectively. This work demonstrates the potential of using biorenewable solvents without additives for the processing of OPV active layers, opening the door to large-scale and green manufacturing of organic solar cells.
PubMed: 37469392
DOI: 10.1021/acsenergylett.3c00891 -
Molecules (Basel, Switzerland) Jul 2023A sustainable enzymatic strategy for the preparation of amides by using lipase B as the biocatalyst and cyclopentyl methyl ether as a green and safe solvent was...
A sustainable enzymatic strategy for the preparation of amides by using lipase B as the biocatalyst and cyclopentyl methyl ether as a green and safe solvent was devised. The method is simple and efficient and it produces amides with excellent conversions and yields without the need for intensive purification steps. The scope of the reaction was extended to the preparation of 28 diverse amides using four different free carboxylic acids and seven primary and secondary amines, including cyclic amines. This enzymatic methodology has the potential to become a green and industrially reliable process for direct amide synthesis.
PubMed: 37570676
DOI: 10.3390/molecules28155706 -
PloS One 2023The current study is designed to synthesize gold nanoparticles using Ajuga bracteosa extract, which is a highly known medicinal herb found in the northern Himalayas. The...
The current study is designed to synthesize gold nanoparticles using Ajuga bracteosa extract, which is a highly known medicinal herb found in the northern Himalayas. The synthesized gold nanoparticles were initially characterized by UV-Vis spectrophotometer, SEM, FTIR, pXRD, and, GC-MS. Antibacterial efficacy of A. bracteosa extract, AuNps, and AuNps-free supernatant activity was checked against highly pathogenic clinical isolates of Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa via agar well diffusion method, assuming that supernatant might have active compounds. The Nps-free supernatant showed the maximum antibacterial activity against E. coli (20.8±0.3 mm), Staphylococcus aureus (16.5±0.5), and Pseudomonas aeruginosa (13±0.6). While green synthesized AuNps showed effective antibacterial activity (Escherichia coli (16.4±0.3mm), Staphylococcus aureus (15.05±0.5mm), and Pseudomonas aeruginosa (11.07±0.6mm)) which was high compared to A. bracteosa extract. Anticancer activity was assessed by MTT assay on U87 and HEK293 cell lines. Aj-AuNps have an antigrowth effect on both the cell lines however Aj-AuNps-free supernatant which was also evaluated along with the Aj-AuNps, showed high toxicity toward HEK293 cell line compared to U87. Further, the GC-MS analysis of supernatant showed the presence of resultant toxic compounds after the reduction of gold salt, which include Trichloromethane, Propanoic acid, 2-methyl-, methyl ester, Methyl isovalerate, Pentanoic acid, 2-hydroxy-4-methyl-, Benzene-propanoic acid, and alpha-hydroxy. Based on the observation small molecular weight ligands of Ajuga bracteosa were analyzed in-silico for their binding efficacy towards selected membrane proteins of our target pathogens. RMSD is also calculated for the best docked protein ligand pose. The results revealed that among all listed ligands, Ergosterol and Decacetylajugrin IV have high virtuous binding affinities towards the membrane proteins of targeted pathogens. The current findings revealed that the Aj-AuNps are good antibacterial as well as anticancerous agents while the Nps-free supernatant is also exceedingly effective against resistant pathogens and cancer cell lines.
Topics: Humans; Ajuga; Propionates; Gold; Escherichia coli; Ligands; HEK293 Cells; Metal Nanoparticles; Anti-Bacterial Agents; Staphylococcus aureus; Plant Extracts; Microbial Sensitivity Tests; Green Chemistry Technology
PubMed: 37549158
DOI: 10.1371/journal.pone.0282485