Neonatal LPS exposure reduces ATP8A2 level in the prefrontal cortex in mice via increasing IFN-γ level

Neonatal IL-4 Over-Exposure is Accompanied by Macrophage Accumulation in Dura Mater After Instant Anti-inflammatory Cytokine Response in CSF

Multiple studies have shown that clinical events resulting into neonatal IL-4 over-exposure, such as asthma in early life and food allergy, were associated with brain damage and that the neuroinflammation induced by them might lead to cognitive impairments, anxiety-/depressive-like behaviors. IL-4 is the most major elevated cytokine in periphery when these clinical events occur and peripheral IL-4 level positively correlates with the severity of those events. Our previous studies have verified that neonatal IL-4 over-exposure induced a delayed neuroinflammatory damage in rodents, which might have adverse implications for brain development and cognition. Neuroinflammation in brain parenchyma is often accompanied by changes in CSF cytokines levels. However, whether the cytokines levels in CSF change after neonatal IL-4 over-exposure is unknown. Here, we found a delayed pro-inflammatory cytokines response (higher IL-6, IL-1β and, TNF levels) in both hippocampus and CSF after an instant anti-inflammatory cytokine response in IL-4 over-exposed rats. Moreover, the pro-inflammatory cytokines response appeared earlier in CSF than in hippocampus. The level of each of the pro-inflammatory cytokines in CSF positively correlated with that in hippocampus at the age of postnatal day 42. More microglia numbers/activation and higher M-CSF level in the hippocampus in IL-4 over-exposed rats were also observed. Furthermore, there were more macrophages with inflammatory activation in dural mater of IL-4 over-exposed rats. In sum, neonatal IL-4 over-exposure in rats induces delayed inflammation in CSF, suggesting CSF examination may serve as a potential method in predicting delayed neuroinflammation in brain following neonatal IL-4 over-exposure.

Blocking coprophagy increases the levels of inflammation and depression in healthy mice as well as mice receiving fecal microbiota transplantation from disease model mice donors

Rodents have been extensively used as animal models in microbiome studies. However, all rodents have a habitual nature called coprophagy, a phenomenon that they self-reinoculate feces into their gastrointestinal tract. Recent studies have shown that blocking coprophagy can alter rodents' diversity of gut microbiota, metabolism, neurochemistry, and cognitive behavior. However, whether rodents' coprophagy behavior affects the levels of inflammation and depression is unclear. In order to address this problem, we first blocked coprophagy in healthy mice. It displayed an increase in the levels of depression, verified by depressive-like behaviors and mood-related indicators, and inflammation, verified by the increased levels of the pro-inflammatory cytokine, in coprophagy-blocked mice. Furthermore, we transplanted fecal microbiota from chronic restraint stress (CRS) depression model mice and lipopolysaccharide (LPS) inflammation model mice to healthy recipient mice, respectively. It showed that the disease-like phenotypes in the coprophagy-blocked group were worse than those in the coprophagy-unblocked group, including severer depressive symptoms and higher levels of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α and IFN-γ) in serum, prefrontal cortex (PFC), and hippocampus (HIP). These findings showed that blocking coprophagy in mice not only increased the levels of inflammation and depression in healthy mice but also aggravated inflammation and depression induced by fecal microbiota from disease donors. The discovery may provide a vital reference for future research involving FMT in rodents.

Cow's milk αS1-casein is more sensitizing than goat's milk αS1-casein in a mouse model

The aim of this study was to compare the sensitization of α_S1-CN in cow and goat's milk in a mouse model. Fifty mice were divided into control group, adjuvant control group, cow's milk α_S1-CN sensitized group, goat's milk α_S1-CN sensitized group and cross sensitized group. Cow's and goat's milk α_S1-CN were used to establish a mouse sensitization model. The results showed that cow's milk α_S1-CN had higher allergenicity than goat's milk α_S1-CN, as can be seen in significantly increased s-IgE and Th2 cell-related inflammatory factors, the proportion of Th2, and the expression of Th2 cell-related transcription factors. Furthermore, the sensitization of cow's milk α_S1-CN damaged the intestinal barrier of mice, caused the leakage of LPS, activated the TLR4-NFκB pathway, and thus resulted in the increase of IFN-γ. In addition, mice allergic to cow's milk α_S1-CN were less sensitized to goat's milk α_S1-CN.