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Background: Lipid droplets (LD), lipid-storing organelles containing neutral lipids like glycerolipids and cholesterol, are increasingly accepted as hallmarks of inflammation. The nuclear paraspeckle assembly transcript 1 (NEAT1), a long non-coding RNA with over 200 nucleotides, exerts an indispensable impact on regulating both LD agglomeration and autophagy in multiple neurological disorders. However, knowledge as to how NEAT1 modulates the formation of LD and associated signaling pathways is limited. Methods: In this study, primary microglia were isolated from newborn mice and exposed to oxygen-glucose-deprivation/reoxygenation (OGD/R). To further explore NEAT1-dependent mechanisms, an antisense oligonucleotide (ASO) was adopted to silence NEAT1 under in vitro conditions. Studying NEAT1-dependent interactions with regard to autophagy and LD agglomeration under hypoxic conditions, the inhibitor and activator of autophagy 3-methyladenine (3-MA) and rapamycin (RAPA) were used, respectively. In a preclinical stroke model, mice received intraventricular injections of ASO NEAT1 or control vectors in order to yield NEAT1 knockdown. Analysis of readout parameters included qRT-PCR, immunofluorescence, western blot assays, and behavioral tests. Results: Microglia exposed to OGD/R displayed a temporal pattern of NEAT1 expression, peaking at four hours of hypoxia followed by six hours of reoxygenation. After effectively silencing NEAT1, LD formation and autophagy-related proteins were significantly repressed in hypoxic microglia. Stimulating autophagy in ASO NEAT1 microglia under OGD/R conditions by means of RAPA reversed the downregulation of LD agglomeration and perilipin 2 (PLIN2) expression. On the contrary, application of 3-MA promoted repression of both LD agglomeration and expression of the LD-associated protein PLIN2. Under in vivo conditions, NEAT1 was significantly increased in mice at 24 h post-stroke. Knockdown of NEAT1 significantly alleviated LD agglomeration and inhibited autophagy, resulting in improved cerebral perfusion, reduced brain injury and increased neurological recovery. Conclusion: NEAT1 is a key player of LD agglomeration and autophagy stimulation, and NEAT1 knockdown provides a promising therapeutic value against stroke. [ABSTRACT FROM AUTHOR]

We have carried out the reactive force field simulations on the pyrolysis process of the transformer insulating oil at different temperatures from 2900 to 3500 K. The selected principal components of the oil molecules are alkanes (C15H32), cycloalkanes (C15H28), and aromatics (C15H16). The effects of formic acid (HCOOH) and acetic acid (CH3COOH) on the pyrolysis mechanism of insulating oils are also studied. The calculated results suggest that with the increasing temperatures, the cracking process of three types of oil molecules accelerates and their speeds of cracking decrease in this order: C15H32 > C15H28 > C15H16. The main pyrolysis products are C2H4, CH4, C2H2, ·CH3, ·C2H3, etc. For the mixture of three types of hydrocarbons, the C2H4 is initially the most abundant product but its concentration decreases gradually and finally the C2H2 and CH4 become the major products. The variation trend of the number of C‒C bonds indicates that the C‒C bonds of oil molecules (especially C15H32 molecules) are broken rapidly at the early stage of pyrolysis process to produce small molecular fragments and then these small fragments are recombined into new pyrolysis products. The evolution of the different types of carbon atoms (sp3-C, sp2-C, sp-C) shows that the sp3-C atoms are initially converted to sp2-C atoms. After the early stage of reactions, many sp2-C atoms are finally turned into sp-C atoms. The addition of formic acid and acetic acid in the insulating oils leads to the formation of the CO and H2O molecules. Both the acetic acid and formic acid could accelerate the pyrolysis process of oil molecules and could further increase the degree of unsaturation of products, which is consistent with the experimental observations. [ABSTRACT FROM AUTHOR]