Transient Receptor Potential Ankyrin 1 (TRPA1) is a non-selective cation channel involved in sensitivity to a plethora of irritating agents and endogenous mediators of oxidative stress. TRPA1 influences neuroinflammation and macrophage and lymphocyte functions, but its role is controversial in immune cells. We reported earlier a detectable, but orders-of-magnitude-lower level of Trpa1 mRNA in monocytes and lymphocytes than in sensory neurons by qRT-PCR analyses of cells from lymphoid organs of mice. Our present goals were to (a) further elucidate the expression of Trpa1 mRNA in immune cells by RNAscope in situ hybridization (ISH) and (b) test the role of TRPA1 in lymphocyte activation. RNAscope ISH confirmed that Trpa1 transcripts were detectable in CD14⁺ and CD4⁺ cells from the peritoneal cavity of mice. A selective TRPA1 agonist JT010 elevated Ca²⁺ levels in these cells only at high concentrations. However, a concentration-dependent inhibitory effect of JT010 was observed on T-cell receptor (TcR)-induced Ca²⁺ signals in CD4⁺ T lymphocytes, while JT010 neither modified B cell activation nor ionomycin-stimulated Ca²⁺ level. Based on our present and past findings, TRPA1 activation negatively modulates T lymphocyte activation, but it does not appear to be a key regulator of TcR-stimulated calcium signaling.

Alzheimer's disease (AD) is an increasing health and social problem worldwide with prevalent cholinergic cell involvement. To reveal the details of the exact mechanisms, further preclinical studies in animals are needed. Our aim was to create a mouse model that represents the progression of AD with easy cholinergic manipulation. The 3xTg-AD and ChAT-Cre strains were crossbred. After serial genotyping, a colony, homozygote for all four genes (PSEN1, APPSwe, tauP301L and Cre; 3xAD-ChAT-Cre) was established. The presence of amyloid-β (Aβ) plaques and phosphor-Tau (pTau) aggregates was confirmed by immunohistochemistry. To test the functionality of the Cre enzyme, a stimulating DREADD virus (AAV8-hSyn-DIO-hM3Dq-mCherry) was injected unilaterally into the nucleus basalis magnocellularis, and clozapine-N-oxide-induced c-Fos activation was compared between the two hemispheres. Behavioral characterization was performed using the Y-maze, social discrimination (SDT), single pellet reaching (SPR), fox odor (FOT), and splash tests (ST). Food, water consumption and body weight change were investigated. Immunostaining and RNAscope confirmed the expression of Cre in ChAT-positive cells and the progressive appearance of pathological hallmarks (Aβ and pTau). The c-Fos activity was significantly increased in the virus-injected hemisphere. Compared with control mice, 3xAD-ChAT-Cre mice showed decreased locomotion (Y-maze, SDT, FOT), increased anxiety (FOT, ST) and weaker fine motor skills (SPR). In conclusion, newly created animals have a functional Cre recombinase enzyme in cholinergic cells. Additionally, the animals presented the pathophysiological hallmarks of AD in specific brain areas and maintained the typical behavioral alterations previously reported in 3xTg-AD mice. Thus, this strain seems to be appropriate for further studies.

Fast and precise methods are important in chemical and physical analysis, but determination of concentration of selected components in mixtures may have special difficulties. Excitation-emission matrices (EEM) are widely used in characterizing fluorescence emission. Based on these primary data, we present an improvement of matrix isopotential synchronous fluorimetry (MISF) and a method which ensures a very fast multicomponent analysis. MISF is generally combined with derivative technique (DMISF) to be able to eliminate the contribution of the background emission. Unfortunately, it is too sensitive to noises and fluctuations; thus the concentration region where it can be used, was limited until now. Our first aim was to reduce the influence of measurement errors and to increase the sensitivity of known MISF method by more than one order of magnitude. As a further result, using improved MISF, we got a method which ensures very fast determination of the wanted compound's concentration both in presence of one- or even two-component background of unknown concentration.

Exosomes carry bioactive macromolecules driving sepsis pathogenesis, but the mechanisms underlying macrophage-to-hepatocyte communication during systemic inflammation remain poorly understood. We investigated how sepsis-induced macrophage exosomes are involved in remote intercellular crosstalk with hepatic cells via transcription factor-encoding mRNA cargo. Human monocytic THP-1 macrophages were stimulated with lipopolysaccharide (LPS), followed by exosome isolation, recipient cell uptake verification, and high-throughput RNA sequencing cargo analysis. To functionally reconstruct downstream signaling in recipient cells, exosome-enriched MAFB mRNA was transiently overexpressed in a HepG2 cell model, with subsequent expression changes mapped at both the transcript and protein levels using quantitative PCR and Western blot analyses. This ectopic MAFB expression directly upregulates the expression of microRNA-155 (miR-155). Crucially, elevated miR-155 acts as a post-transcriptional repressor that directly targets and downregulates JARID2 and H3F3A mRNAs and their corresponding protein products within the liver cells, orchestrating a “repressor-of-repressors” disinhibition cascade that drives net chromatin remodeling and activation of downstream hepatic target genes. This study demonstrates that sepsis alters exosomal transcription factor mRNA cargo and delineates a mechanistic downstream pathway—MAFB → ↑miR155 → ↓Jarid2 & ↓H3F3A → Chromatin Remodeling → Downstream Hepatic Gene Activation pathway—that provides novel, specific molecular checkpoints for therapeutic intervention in sepsis-induced liver injury.