Shovgi Huseynov

The basic helix-loop-helix transcription factor neuronal PAS (Per, Arnt, Sim) domain protein 3 (NPAS3) provides transcriptional regulation of metabolic pathways and is highly expressed in astrocytes. NPAS3 variants have been associated with cognitive dysfunction under several neuropsychiatric conditions, but the underlying brain cell type–specific mechanisms remain obscure. Here, we report that NPAS3 is a key regulator of mitochondrial bioenergetics in astrocytes in the mouse brain. Selective deletion of Npas3 in mature astrocytes decreases expression of mitochondrial glutamate carrier 2 involved in glutamate oxidation, leading to reduced oxidative phosphorylation and lactate production in astrocytes. This deficit reduces intrinsic excitability, dendritic spine density, and excitatory synaptic transmission of medial prefrontal cortex (mPFC) pyramidal neurons. Mice with Npas3 -deficient mPFC astrocytes exhibit impaired trace fear conditioning, which is rescued by lactate treatment. Thus, the present study demonstrates a mechanistic link between NPAS3-dependent astrocyte mitochondrial bioenergetics and cognitive function and provides insights for glia-targeting treatment of cognitive dysfunction in neuropsychiatric disease.

Astrocytes express mu/µ opioid receptors, but the function of these receptors remains poorly understood. We evaluated the effects of astrocyte-restricted knockout of µ opioid receptors on reward- and aversion-associated behaviors in mice chronically exposed to morphine. Specifically, one of the floxed alleles of the Oprm1 gene encoding µ opioid receptor 1 was selectively deleted from brain astrocytes in Oprm1 inducible conditional knockout (icKO) mice. These mice did not exhibit changes in locomotor activity, anxiety, or novel object recognition, or in their responses to the acute analgesic effects of morphine. Oprm1 icKO mice displayed increased locomotor activity in response to acute morphine administration but unaltered locomotor sensitization. Oprm1 icKO mice showed normal morphine-induced conditioned place preference but exhibited stronger conditioned place aversion associated with naloxone-precipitated morphine withdrawal. Notably, elevated conditioned place aversion lasted up to 6 weeks in Oprm1 icKO mice. Astrocytes isolated from the brains of Oprm1 icKO mice had unchanged levels of glycolysis but had elevated oxidative phosphorylation. The basal augmentation of oxidative phosphorylation in Oprm1 icKO mice was further exacerbated by naloxone-precipitated withdrawal from morphine and, similar to that for conditioned place aversion, was still present 6 weeks later. Our findings suggest that µ opioid receptors in astrocytes are linked to oxidative phosphorylation and they contribute to long-term changes associated with opioid withdrawal.

The paper investigates oscillatory processes in solar flares based on observational data obtained by a 12-meter radio telescope at a frequency f=3 GHz belonging to the Ionosphere Institute of the Kazakhstan Republic. The results of a brief review of methods for processing non-stationary time series suggest that the requirement of adaptability is also important. It is shown that this possibility is provided by the method proposed by Norden Huang. For clarity, the method of implementing EMD (Empirical Mode Decomposition) - the method of decomposing signals into functions (modes) will be considered using the example of a digital signal array x(t). In order to obtain more realistic results, the type of series was determined using fractal analysis. It is shown that at this stage, for the reliability of obtaining CPP, it is necessary to carry out visual control and compare the results obtained by different methods. The paper shows that one of the important conditions is to add to the simulation the presence of quasi-periodic pulsations in the process to explain the physics of the phenomenon of flare events occurring on the Sun. Accordingly, an understanding of the specific mechanisms responsible for the appearance of checkpoints, in combination with their observed parameters, makes it possible to diagnose flare regions and can significantly improve flare prediction.