Retinoic acid induced specific changes in the phosphoproteome of C17.2 neural stem cells

Retinoic acid (RA), a vitamin A derivative, is an effective cell differentiating factor which plays critical roles in neuronal differentiation induction and the production of neurotransmitters in neurons. However, the specific changes in phosphorylation levels and downstream signalling pathways associated with RA remain unclear. This study employed qualitative and quantitative phosphoproteomics approaches based on mass spectrometry to investigate the phosphorylation changes induced by RA in C17.2 neural stem cells (NSCs). Dimethyl labelling, in conjunction with TiO2 phosphopeptide enrichment, was utilized to profile the phosphoproteome of self-renewing and RA-induced differentiated cells in C17.2 NSCs. The results of our study revealed that, qualitatively, 230 and 14 phosphoproteins were exclusively identified in the self-renewal and RA-induced groups respectively. Quantitatively, we successfully identified and quantified 177 unique phosphoproteins, among which 70 exhibited differential phosphorylation levels. Analysis of conserved phosphorylation motifs demonstrated enrichment of motifs corresponding to cyclin-dependent kinase and MAPK in the RA-induced group. Additionally, through a comprehensive literature and database survey, we found that the differentially expressed proteins were associated with the Wnt/β-catenin and Hippo signalling pathways. This work sheds light on the changes in phosphorylation levels induced by RA in C17.2 NSCs, thereby expanding our understanding of the molecular mechanisms underlying RA-induced neuronal differentiation.

Effects of Multiple High-Dose Methamphetamine Administration on Enteric Dopaminergic Neurons and Intestinal Motility in the Rat Model

Several studies have identified the effects of methamphetamine (MA) on central dopaminergic neurons, but its effects on enteric dopaminergic neurons (EDNs) are unclear. The aim of this study was to investigate the effects of MA on EDNs and intestinal motility. Male Sprague-Dawley rats were randomly divided into MA group and saline group. The MA group received the multiple high-dose MA treatment paradigm, while the controls received the same saline treatment. After enteric motility was assessed, different intestinal segments (i.e., duodenum, jejunum, ileum, and colon) were taken for histopathological, molecular biological, and immunological analysis. The EDNs were assessed by measuring the expression of two dopaminergic neuronal markers, dopamine transporter (DAT) and tyrosine hydroxylase (TH), at the transcriptional and protein levels. We also used c-Fos protein, a marker of neural activity, to detect the activation of EDNs. MA resulted in a significant reduction in TH and DAT mRNA expression as well as in the number of EDNs in the duodenum and jejunum (p < 0.05). MA caused a dramatic increase in c-Fos expression of EDNs in the ileum (p < 0.001). The positional variability of MA effects on EDNs paralleled the positional variability of its effect on intestinal motility, as evidenced by the marked inhibitory effect of MA on small intestinal motility (p < 0.0001). This study found significant effects of MA on EDNs with locational variability, which might be relevant to locational variability in the potential effects of MA on intestinal functions, such as motility.

FTO-mediated m6A modification promotes malignant transformation of gastric mucosal epithelial cells in chronic Cag A+ Helicobacter pylori infection

OBJECTIVES

Cag A+ Helicobacter pylori chronic infection cause malignant transformation of the human gastric mucosa. N6-methyladenosine (m6A) modifications are the most common and abundant mRNA modifications and one of the pathways affecting tumorigenicity and tumor progression. However, the role of m6A modification in the process of chronic H. pylori infection leading to malignant transformation of gastric mucosa is unclear.

METHODS

In this study, we used Cag A- and Cag A+H. pylori chronic infection to establish cellular models in GES-1 cells and analyzed the cellular morphology, proliferation, apoptosis, invasiveness and tumorigenicity of gastric mucosal epithelial cells. The m6A expression levels of GES-1 cells after chronic infection with Cag A- and Cag A+H. pylori were examined, and modifying effect of FTO (the fat mass and obesity-associated protein) on CD44 was verified by MeRIP-qPCR. Finally, the FTO expression changes and m6A expression levels were further validated in clinical gastric cancer tissues.

RESULTS

Chronic Cag A+H. pylori-infected GES-1 cells exhibit altered cell morphology, apoptosis inhibition, abnormal proliferation, enhanced migration, colony formation, and increased stem cell-like properties. Meanwhile, FTO and CD44 expression was enhanced, and FTO may induce malignant transformation of gastric mucosa by regulating CD44 mRNA m6A methylation modifications.

CONCLUSIONS

We verified the effect of chronic stimulation of Cag A+H. pylori on malignant transformation of gastric mucosal epithelium. revealing the possibility of FTO in promoting malignant transformation of gastric mucosa by modifying CD44 mRNA methylation, suggesting that FTO expression is a potential molecule for malignant transformation of gastric mucosal epithelial cells.

COVID-19 vaccination status and associated factors among lactating women during the COVID-19 outbreak: a cross-sectional study in southern China

OBJECTIVES

Different countries and institutions around the world have debated whether lactating women should receive the COVID-19 vaccine during the COVID-19 pandemic. In China, lactating is not a contraindication to vaccination, but many women are still hesitant to get vaccinated. The purpose of this study was to investigate the current status of COVID-19 vaccination among lactating women and the related factors affecting vaccination.

METHODS

An online cross-sectional survey involving 506 lactating women was conducted in southern China. We explored the related factors affecting COVID-19 vaccination of lactating women from three aspects: general information, knowledge-attitude-behaviour towards COVID-19 and its vaccine, and postpartum psychological state.

RESULTS

A total of 432 lactating women completed the questionnaire, 198 of whom had received the COVID-19 vaccine. On the knowledge-attitude-behaviour questionnaire on COVID-19 and its vaccines, the vaccinated group scored higher than the unvaccinated group on both the three subdimensions of the questionnaire and the total score (p<0.01). The results of binary logistics regression analysis showed that mixed feeding (OR=2.68, 95% CI: 1.82 to 3.96), longer breastfeeding duration (OR=1.31, 95% CI: 1.16 to 1.49), better physical condition (OR=5.28, 95% CI: 1.82 to 15.32), higher attitude score of COVID-19 and its vaccine (OR=1.18, 95% CI: 1.10 to 1.27), and having a travel history in medium high-risk areas (OR=3.49, 95% CI: 1.46 to 8.37) were significantly associated with COVID-19 vaccination in lactating women. Having a master's degree or above (OR=0.03, 95% CI: 0.01 to 0.30), and having higher anxiety score (OR=0.66, 95% CI: 0.54 to 0.81) and depression score (OR=0.84, 95% CI: 0.75 to 0.93) were inversely associated with COVID-19 vaccination in lactating women.

CONCLUSION

45.8% of lactating women were vaccinated against COVID-19. Education level, feeding methods, duration of breast feeding, travel history in medium high-risk areas, physical condition, attitude score of COVID-19 and its vaccine, anxiety symptom and depressive symptom score were associated with vaccination of lactating women. More interventions based on these factors were needed to reduce concerns for lactating women and increase their vaccination rates.