Transcriptomics Changes in the Peritoneum of Mice with Lipopolysaccharide-Induced Peritonitis

Peripheral inflammation-induced changes in songbird brain gene expression: 3' mRNA transcriptomic approach

Species-specific neural inflammation can be induced by profound immune signalling from periphery to brain. Recent advances in transcriptomics offer cost-effective approaches to study this regulation. In a population of captive zebra finch (Taeniopygia guttata), we compare the differential gene expression patterns in lipopolysaccharide (LPS)-triggered peripheral inflammation revealed by RNA-seq and QuantSeq. The RNA-seq approach identified more differentially expressed genes but failed to detect any inflammatory markers. In contrast, QuantSeq results identified specific expression changes in the genes regulating inflammation. Next, we adopted QuantSeq to relate peripheral and brain transcriptomes. We identified subtle changes in the brain gene expression during the peripheral inflammation (e.g. up-regulation in AVD-like and ACOD1 expression) and detected co-structure between the peripheral and brain inflammation. Our results suggest benefits of the 3'end transcriptomics for association studies between peripheral and neural inflammation in genetically heterogeneous models and identify potential targets for the future brain research in birds.

General Morphological Characteristics of the Results of Experimental Modeling of Aseptic Peritonitis

BACKGROUND

Aseptic peritonitis is a reaction of the local immune system aimed at rejection of a foreign body, which, having antigenic properties, does not (unlike a pathogen) counteract the immune system. The suture materials, namely catgut thread, used in intracavitary surgical operations possess xenogenic properties and can be used for antigenic stimulation of the immune system of the peritoneal cavity. Consequently, we decided to use a catgut suture for antigenic stimulation of the immune system of the peritoneal cavity and to study the morphological features of the results of experimental modeling of aseptic peritonitis in albino rats.

METHOD

The study involved 15 Wistar albino male rats, weighing 286,13 ± 6,26 g. To study the dynamics of destructive changes made by the catgut implant in the peritoneal cavity of the experimental animals, the animals were assigned into three groups in accordance with the time interval of their euthanasia at 3, 7, and 14 days of the experiment.

RESULTS

After modeling an aseptic peritonitis, the investigation the abdominal cavity showed that in four out of five animals of the first group, that is, on day 3 of the experiment, the catgut implant had adhered to the greater omentum. The search for the fifth implant led to an unexpected discovery: we found it conjoined with the second derivative of the visceral peritoneum, similar in structure to the greater omentum, but related to the testes. On day 7, the implant embedded into the peritoneal cavity of the animals, had adhered to the serous formations of the testes in all five cases (100%, three of them - to the left epididymal omentum, and another two - to the right one). On day 14 (n = 5) it was found that in three cases it had adhered to the serous formations of the testes (60%, one of them to the left epididymal omentum, another two - to the right one) and in two cases it had adhered to the greater omentum (40%).

CONCLUSION

During the experiment on implantation of a xenogenic substrate in the form of flat bundles made from the catgut thread into the peritoneal cavity of sexually mature male rats, it was found for the first time that their acceptors were not only the greater omentum, but also two derivatives of the peritoneum, homeomorphic to it and associated with the epididymides, which we reasonably called epididymal omenta and described in details.

Honokiol reduces fungal burden and ameliorate inflammation lesions of Aspergillus fumigatus keratitis via Dectin-2 down-regulation

PURPOSE

To screen and identify the mechanism of honokiol on anti-fungi and anti-inflammation in fungal keratitis (FK) through bioinformatic analysis and biological experiments.

METHODS

Transcriptome profile demonstrated differential expression genes (DEGs) of Aspergillus fumigatus keratitis between PBS-treated and honokiol-treated groups via bioinformatics analyses. Inflammatory substances were quantified by qRT-PCR, Western blot and ELISA, and macrophage polarization was examined by flow cytometry. Periodic acid Schiff staining and morphological interference assay were used to detect hyphal distribution in vivo and fungal germination in vitro, respectively. Electron microscopy was to illustrate hyphal microstructure.

RESULTS

Illumina sequencing demonstrated that compared with the honokiol group, 1175 up-regulated and 383 down-regulated genes were induced in C57BL/6 mice Aspergillus fumigatus keratitis with PBS treatment. Through GO analysis, some differential expression proteins (DEPs) played major roles in biological processes, especially fungal defense and immune activation. KEGG analysis provided fungus-related signaling pathways. PPI analysis demonstrated that DEPs from multiple pathways form a close-knit network, providing a broader context for FK treatment. In biological experiments, Dectin-2, NLRP3 and IL-1β were upregulated by Aspergillus fumigatus to evaluate immune response. Honokiol could reverse the trend, comparable to Dectin-2 siRNA interference. Meanwhile, honokiol could also play an anti-inflammatory role via promoting M2 phenotype polarization. Moreover, honokiol reduced hyphal distribution in the stroma, delayed germination, and destroyed the hyphal cell membrane in-vitro.

CONCLUSIONS

Honokiol possesses anti-fungal and anti-inflammatory effects in Aspergillus fumigatus keratitis and may develop a potential and safe therapeutic modality for FK.

TAK-242 Ameliorates Hepatic Fibrosis by Regulating the Liver-Gut Axis

Objective. The aims of this study were to investigate the impact of TAK-242 on the Toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88)/nuclear transcription factor-κB (NF-κB) signal transduction pathway in rats with hepatic fibrosis (HF) using the liver gut axis and to investigate the molecular mechanism of its intervention on HF. Methods. SPF grade SD male rats were randomly allocated to the control, model, and TAK-242 groups. For 8 weeks, the model and TAK-242 groups received 3 mL·kg-1 (the initial dose 5 mL·kg-1) intraperitoneal injections of 40% CCL4 olive oil solution. TAK-242 (5 mg·kg-1) was administered once a day for 5 days after modeling. The pathological alterations of liver and small intestine tissues in each group were observed using H&E and Masson staining. ELISA was used to measure serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), direct bilirubin (DBIL), total bilirubin (TBIL), interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α). RT-qPCR was utilized to identify the mRNA expression level of IL-1β, IL-6, TNF-α, TLR4, MyD88, and NF-κB in rat liver and small intestine tissues. The protein level of IL-1β, IL-6, TNF-α, TLR4, MyD88, and NF-κB protein in rat liver and small intestine tissues was determined utilizing Western blot and IHC. Results. TAK-242 significantly reduced AST, ALT, TBIL, and DBIL expression in HF rats’ serum ( $P<0.01$ ) and alleviated liver tissue injury. Hematoxylin-eosin (H&E) and Masson staining revealed inflammatory cell infiltration and fibrous proliferation in the liver and small intestine tissue in the model group and partial cell swelling in the TAK-242 group, which indicated a considerable improvement compared to the model group. RT-qPCR, Western blot, and IHC data indicated that TAK-242 reduced the IL-1β, IL-6, TNF-α, TLR4, MyD88, and NF-κB expression in the liver and small intestine tissues of HF rats. Conclusion. TAK-242 might downregulate the TLR4/MyD88/NF-κB signal pathway through the liver-gut axis, suppress the inflammatory response, and eventually alleviate HF in rats.