RÉSUMÉ
BACKGROUND: Helicobacter pylori (H. pylori) infection can cause extensive apoptosis of gastric epithelial cells, serving as a critical catalyst in the progression from chronic gastritis, gastrointestinal metaplasia, and atypical gastric hyperplasia to gastric carcinoma. Prompt eradication of H. pylori is paramount for ameliorating the pathophysiological conditions associated with chronic inflammation of the gastric mucosa and the primary prevention of gastric cancer. Acacetin, which has multifaceted pharmacological activities such as anti-cancer, anti-inflammatory, and antioxidative properties, has been extensively investigated across various domains. Nevertheless, the impact and underlying mechanisms of action of acacetin on H. pylori-infected gastric mucosal epithelial cells remain unclear. AIM: To explore the defensive effects of acacetin on apoptosis in H. pylori-infected GES-1 cells and to investigate the underlying mechanisms. METHODS: GES-1 cells were treated with H. pylori and acacetin in vitro. Cell viability was assessed using the CCK-8 assay, cell mortality rate via lactate dehydrogenase assay, alterations in cell migration and healing capacities through the wound healing assay, rates of apoptosis via flow cytometry and TUNEL staining, and expression levels of apoptosis-associated proteins through western blot analysis. RESULTS: H. pylori infection led to decreased GES-1 cell viability, increased cell mortality, suppressed cell migration, increased rate of apoptosis, increased expressions of Bax and cle-caspase3, and decreased Bcl-2 expression. Conversely, acacetin treatment enhanced cell viability, mitigated apoptosis induced by H. pylori infection, and modulated the expression of apoptosis-regulatory proteins by upregulating Bcl-2 and downregulating Bax and cleaved caspase-3. CONCLUSION: Acacetin significantly improved GES-1 cell viability and inhibited apoptosis in H. pylori-infected GES-1 cells, thereby exerting a protective effect on gastric mucosal epithelial cells.
RÉSUMÉ
BACKGROUND: Caloric restriction (CR) might be effective for alleviating/preventing Alzheimer's disease (AD), but the biological mechanisms remain unclear. In the current study, we explored whether CR caused an alteration of gut microbiome and resulted in the attenuation of cognitive impairment of AD animal model. METHODS: Thirty-week-old male APP/PS1 transgenic mice were used as AD models (AD mouse). CR was achieved by 30% reduction of daily free feeding (ad libitum, AL) amount. The mice were fed with CR protocol or AL protocol for six consecutive weeks. RESULTS: We found that with CR treatment, AD mice showed improved ability of learning and spatial memory, and lower levels of Aß40, Aß42, IL-1ß, TNF-α, and ROS in the brain. By sequencing 16S rDNA, we found that CR treatment resulted in significant diversity in composition and abundance of gut flora. At the phylum level, Deferribacteres (0.04%), Patescibacteria (0.14%), Tenericutes (0.03%), and Verrucomicrobia (0.5%) were significantly decreased in CR-treated AD mice; at the genus level, Dubosiella (10.04%), Faecalibaculum (0.04%), and Coriobacteriaceae UCG-002 (0.01%) were significantly increased in CR-treated AD mice by comparing with AL diet. CONCLUSIONS: Our results demonstrate that the attenuation of AD following CR treatment in APP/PS1 mice may result from alterations in the gut microbiome. Thus, gut flora could be a new target for AD prevention and therapy.
Sujet(s)
Maladie d'Alzheimer , Précurseur de la protéine bêta-amyloïde , Restriction calorique , Microbiome gastro-intestinal , Souris transgéniques , Animaux , Microbiome gastro-intestinal/physiologie , Restriction calorique/méthodes , Maladie d'Alzheimer/microbiologie , Maladie d'Alzheimer/diétothérapie , Maladie d'Alzheimer/prévention et contrôle , Mâle , Souris , Précurseur de la protéine bêta-amyloïde/génétique , Préséniline-1/génétique , Peptides bêta-amyloïdes/métabolisme , Modèles animaux de maladie humaine , Apprentissage du labyrinthe/physiologie , Encéphale/métabolisme , Souris de lignée C57BLRÉSUMÉ
Partial denitrification (PD) is an alternative to providing NO2- for the anaerobic ammonium oxidation (anammox) process. In this study, three upflow anaerobic sludge blankets (UASB) were used to investigate the effect of an external electric field on PD performance. The results indicated that the maximum nitrite transformation ratio (NTR) reached 76.3 %, with an average NTR of 54.1 %, in the presence of external electric field, whereas the average NTR of the control was only 49.8 %. The fitted maximum specific nitrate reduction rates of PD1, PD2, and PD3 were 83.7, 90.5, and 92.3 mg N g-1VSS h-1, respectively, according to the Haldane model analysis. Microbial community analysis demonstrated that the abundance of Thauera, Comamonas, and Accumulibacter increased with electric assistance. In summary, UASB reactor with electrodes set in the upper region was most feasible for the stable PD process, providing an alternative for developing a coupled PD-anammox process.
Sujet(s)
Dénitrification , Eaux d'égout , Anaérobiose , Azote/analyse , Bioréacteurs , Oxydoréduction , NitritesRÉSUMÉ
Background: Late-onset depression (LOD) and early-onset depression (EOD) exhibit different pathological mechanisms and clinical phenotypes, including different extents of olfactory dysfunction. However, the brain abnormalities underlying the differences in olfactory dysfunction between EOD and LOD remain unclear. Objective: The aim of this study was to compare the functional connectivity (FC) patterns of olfactory regions between EOD patients and LOD patients and examine their relationship with cognitive function. Methods: One hundred and five patients with EOD, 101 patients with LOD and 160 normal controls (NCs) were recruited for the present study. Participants underwent clinical assessment, olfactory testing, cognitive assessments, and magnetic resonance imaging. Eight regions of the primary and secondary olfactory regions were selected to investigate olfactory FC. Results: Patients with LOD exhibited decreased odor identification (OI) compared with patients with EOD and NCs. The LOD group exhibited decreased FC compared with the EOD and NC groups when primary and secondary olfactory regions were selected as the regions of interest (the piriform cortex, lateral entorhinal cortex, and orbital-frontal cortex). Additionally, these abnormal olfactory FCs were associated with decreased cognitive function scores and OI, and the FC between the left orbital-frontal cortex and left amygdala was a partial mediator of the relationship between global cognitive scores and OI. Conclusion: Overall, patients with LOD exhibited decreased FC in both the primary and secondary olfactory cortices compared with patients with EOD, and abnormal olfactory FC was associated with OI dysfunction and cognitive impairment. The FC between the orbital-frontal cortex and amygdala mediated the relationship between global cognitive function and OI.