Macrophages from naked mole-rat possess distinct immunometabolic signatures upon polarization

Grifola frondosa Polysaccharide Ameliorates Inflammation by Regulating Macrophage Polarization of Liver in Type 2 Diabetes Mellitus Rats

SCOPE

Grifola frondosa polysaccharide (GFP) has a positive effect in regulating type 2 diabetes mellitus (T2DM), but the understanding of its regulatory mechanism is still limited. Accumulating evidence suggests that hepatic inflammation is crucial in the onset and progression of insulin resistance (IR) and T2DM. However, the question of whether GFP can modulate T2DM via regulating hepatic inflammation and the underlying mechanism has not yet been reported.

METHODS AND RESULTS

High-fat diet (HFD) fed combined with streptozocin (STZ) injections rat model and Lipopolysaccharides (LPS)-treated bone marrow-derived macrophages (BMDM) model are used. The results showed that GFP intervention reduces weight loss and hyperglycemia symptoms, besides lowers FINS, HOMA-IR, IPGTT-AUC, and IPITT-AUC in T2DM rats. Meanwhile, GFP intervention reduces the secretion level of inflammatory factors and increases the secretion level of anti-inflammatory factors in the liver tissue of T2DM rats. Furthermore, GFP reduces macrophage infiltration in liver tissue, inhibits macrophage M1-type polarization, and promotes M2-type polarization.

CONCLUSIONS

These results suggest that GFP intervention could attenuate the hepatic inflammatory and insulin resistance in T2DM rats by inhibiting hepatic macrophage infiltration and modulating M1/M2 polarization. The findings provide new evidence for GFP in the early prevention and treatment of T2DM.

The infection-tolerant white-footed deermouse tempers interferon responses to endotoxin in comparison to the mouse and rat

The white-footed deermouse Peromyscus leucopus, a long-lived rodent, is a key reservoir in North America for agents of several zoonoses, including Lyme disease, babesiosis, anaplasmosis, and a viral encephalitis. While persistently infected, this deermouse is without apparent disability or diminished fitness. For a model for inflammation elicited by various pathogens, the endotoxin lipopolysaccharide (LPS) was used to compare genome-wide transcription in blood by P. leucopus, Mus musculus, and Rattus norvegicus and adjusted for white cell concentrations. Deermice were distinguished from the mice and rats by LPS response profiles consistent with non-classical monocytes and alternatively-activated macrophages. LPS-treated P. leucopus, in contrast to mice and rats, also displayed little transcription of interferon-gamma and lower magnitude fold-changes in type 1 interferon-stimulated genes. These characteristics of P. leucopus were also noted in a Borrelia hermsii infection model. The phenomenon was associated with comparatively reduced transcription of endogenous retrovirus sequences and cytoplasmic pattern recognition receptors in the deermice. The results reveal a mechanism for infection tolerance in this species and perhaps other animal reservoirs for agents of human disease.

Fishing Innate Immune System Properties through the Transcriptomic Single-Cell Data of Teleostei

The innate immune system is the first line of defense in multicellular organisms. Danio rerio is widely considered a promising model for IIS-related research, with the most amount of scRNAseq data available among Teleostei. We summarized the scRNAseq and spatial transcriptomics experiments related to the IIS for zebrafish and other Teleostei from the GEO NCBI and the Single-Cell Expression Atlas. We found a considerable number of scRNAseq experiments at different stages of zebrafish development in organs such as the kidney, liver, stomach, heart, and brain. These datasets could be further used to conduct large-scale meta-analyses and to compare the IIS of zebrafish with the mammalian one. However, only a small number of scRNAseq datasets are available for other fish (turbot, salmon, cavefish, and dark sleeper). Since fish biology is very diverse, it would be a major mistake to use zebrafish alone in fish immunology studies. In particular, there is a special need for new scRNAseq experiments involving nonmodel Teleostei, e.g., long-lived species, cancer-resistant fish, and various fish ecotypes.

The white-footed deermouse, an infection-tolerant reservoir for several zoonotic agents, tempers interferon responses to endotoxin in comparison to the mouse and rat

The white-footed deermouse Peromyscus leucopus, a long-lived rodent, is a key reservoir for agents of several zoonoses, including Lyme disease. While persistently infected, this deermouse is without apparent disability or diminished fitness. For a model for inflammation elicited by various pathogens, the endotoxin lipopolysaccharide (LPS) was used to compare genome-wide transcription in blood by P. leucopus, Mus musculus and Rattus norvegicus and adjusted for white cell concentrations. Deermice were distinguished from the mice and rats by LPS response profiles consistent with non-classical monocytes and alternatively-activated macrophages. LPS-treated P. leucopus, in contrast to mice and rats, also displayed little transcription of interferon-gamma and lower magnitude fold-changes in type 1 interferon-stimulated genes. This was associated with comparatively reduced transcription of endogenous retrovirus sequences and cytoplasmic pattern recognition receptors in the deermice. The results reveal a mechanism for infection tolerance in this species and perhaps other animal reservoirs for agents of human disease.