Gut microbiota dynamics and fecal SCFAs after colonoscopy: accelerating microbiome stabilization by Clostridium butyricum.

BACKGROUND: Colonoscopy is a classic diagnostic method with possible complications including abdominal pain and diarrhoea. In this study, gut microbiota dynamics and related metabolic products during and after colonoscopy were explored to accelerate gut microbiome balance through probiotics. METHODS: The gut microbiota and fecal short-chain fatty acids (SCFAs) were analyzed in four healthy subjects before and after colonoscopy, along with seven individuals supplemented with Clostridium butyricum. We employed 16S rRNA sequencing and GC-MS to investigate these changes. We also conducted bioinformatic analysis to explore the buk gene, encoding butyrate kinase, across C. butyricum strains from the human gut. RESULTS: The gut microbiota and fecal short-chain fatty acids (SCFAs) of four healthy subjects were recovered on the 7th day after colonoscopy. We found that Clostridium and other bacteria might have efficient butyric acid production through bioinformatic analysis of the buk and assessment of the transcriptional level of the buk. Supplementation of seven healthy subjects with Clostridium butyricum after colonoscopy resulted in a quicker recovery and stabilization of gut microbiota and fecal SCFAs on the third day. CONCLUSION: We suggest that supplementation of Clostridium butyricum after colonoscopy should be considered in future routine clinical practice.

Weizmannia coagulans BCF-01: a novel gastrogenic probiotic for Helicobacter pylori infection control.

The widespread prevalence of Helicobacter pylori infection, particularly in China, contributes to the development of gastrointestinal diseases. Antibiotics have limitations, including adverse reactions and increased antibiotic resistance. Therefore, identification of novel gastrogenic probiotics capable of surviving the acidic gastric environment and effectively combating H. pylori infection has potential in restoring gastric microbiota homeostasis. Five novel strains of human gastrogenic Weizmannia coagulans (BCF-01-05) were isolated from healthy gastric mucosa and characterized using 16S rDNA identification. Acid resistance, H. pylori inhibition, and adherence to gastric epithelial cells were evaluated in in-vitro experiments and the molecular mechanism explored in in-vivo experiments. Among the gastric-derived W. coagulans strains, BCF-01 exhibited the strongest adhesion and H. pylori inhibition, warranting further in-vivo safety evaluation. Through 16S rRNA sequencing of a mouse model, BCF-01 was determined to significantly restore H. pylori-associated gastric dysbiosis and increase the abundance of potential probiotic bacteria. Furthermore, BCF-01 enhanced mucosal tight junction protein expression and inhibited the TLR4-NFκB-pyroptosis signaling pathway in macrophages, as demonstrated by qRT-PCR and western blotting.These findings highlight the potential of BCF-01 in the prevention and control of H. pylori infection. Specifically, treatment with BCF-01 effectively restored gastric microecology and improved H. pylori-mediated mucosal barrier destruction while reducing inflammation through inhibition of the TLR4-NFκB-pyroptosis signaling pathway in macrophages. BCF-01 is a promising alternative to traditional triple therapy for H. pylori infections, offering minimal side effects with high suitability for high-risk individuals.

Macrophages in heterotopic ossification: from mechanisms to therapy.

Heterotopic ossification (HO) is the formation of extraskeletal bone in non-osseous tissues. It is caused by an injury that stimulates abnormal tissue healing and regeneration, and inflammation is involved in this process. It is worth noting that macrophages are crucial mediators of inflammation. In this regard, abundant macrophages are recruited to the HO site and contribute to HO progression. Macrophages can acquire different functional phenotypes and promote mesenchymal stem cell (MSC) osteogenic differentiation, chondrogenic differentiation, and angiogenesis by expressing cytokines and other factors such as the transforming growth factor-ß1 (TGF-ß1), bone morphogenetic protein (BMP), activin A (Act A), oncostatin M (OSM), substance P (SP), neurotrophin-3 (NT-3), and vascular endothelial growth factor (VEGF). In addition, macrophages significantly contribute to the hypoxic microenvironment, which primarily drives HO progression. Thus, these have led to an interest in the role of macrophages in HO by exploring whether HO is a "butterfly effect" event. Heterogeneous macrophages are regarded as the "butterflies" that drive a sequence of events and ultimately promote HO. In this review, we discuss how the recruitment of macrophages contributes to HO progression. In particular, we review the molecular mechanisms through which macrophages participate in MSC osteogenic differentiation, angiogenesis, and the hypoxic microenvironment. Understanding the diverse role of macrophages may unveil potential targets for the prevention and treatment of HO.

Circular RNA 0025984 Ameliorates Ischemic Stroke Injury and Protects Astrocytes Through miR-143-3p/TET1/ORP150 Pathway.

MiR-143-3p is aberrantly expressed in patients with ischemic stroke and associated with ischemic brain injury. However, the underlying mechanisms are largely unknown. Here, we confirmed circ_0025984 and TET1 as a sponge and target of miR-143-3p, respectively, by luciferase reporter assay. In astrocytes, OGD significantly decreased circ_0025984 and TET1 levels but increased miR-143-3p levels, which was also observed in brains of mice with MCAO. Treatment with miR-143-3p inhibitor or circ_0025984 significantly decreased astrocyte apoptosis and autophagy, as well as cerebral injury and neuron loss in mice with MCAO. Notably, TET1 overexpression decreased astrocyte apoptosis and autophagy and induced promoter hypomethylation and expression of ORP150. Our results demonstrated for the first time that circ_0025984 protects astrocytes from ischemia-induced autophagy and apoptosis by targeting the miR-143-3p/TET1 pathway and might inhibit cerebral injury induced by ischemic stroke. Furthermore, our data revealed the important positive regulation of ORP150 by TET1, which could be associated with its neuroprotective role. Graphical abstract Model for signaling pathway of circ_0025984/miR-143-3p/TET1 inastrocytes cultured under OGD. In astrocytes, circ_0025984 acts as a sponge of miR-143-3p, which directly targets TET1 and decreases its expression (A). After translocatinginto the nucleus, TET1 binds to the promoter of ORP150, converts 5mC into 5hmC,leading to DNA demethylation and increased expression of ORP150 (B). In astrocytescultured under OGD, ER stress is induced and eventually leads to apoptosis andautophagy mediated by ATG7, which is regulated by circ_0025984 via ORP150 andGRP78 (C).

Combination of endothelial progenitor cells and BB-94 significantly alleviates brain damage in a mouse model of diabetic ischemic stroke.

Ischemic stroke is a complication of chronic macrovascular disease in type 2 diabetes. However, the pathogenesis of diabetic ischemic stroke has not yet been fully clarified. The aim of the present study was to investigate the underlying effects of endothelial progenitor cells (EPCs) and the matrix metalloproteinase inhibitor BB-94 on diabetic stroke. In vitro experiments were performed using oxygen-glucose deprivation/reoxygenation (OGD/R) model cells, established using HT22 mouse hippocampal cells. MTT assays and flow cytometry revealed that BB-94 prominently induced the proliferation of the OGD/R model cells and prevented their apoptosis. When EPCs and BB-94 were applied to the OGD/R model cells in combination, proliferation was further accelerated and oxidative damage was attenuated. In vivo experiments were also performed using a middle cerebral artery occlusion (MCAO) mouse model. The results of modified neurological severity scoring and oxidative stress marker analysis demonstrated that EPCs and BB-94 prominently alleviated cerebral ischemia/reperfusion injury in the MCAO model mice. Furthermore, reverse transcription-quantitative PCR and western blot assays revealed that EPCs in combination with BB-94 significantly downregulated the expression of matrix metalloproteinases (MMPs) and upregulated the expression of tissue inhibitor of metalloproteinases 1 in OGD/R cells and MCAO model mice. The results suggest that EPCs were successfully isolated and identified, and the OGD/R cell and MCAO mouse models were successfully established. They also indicate that EPCs alone or in combination with BB-94 may exert protective effects against ischemic stroke via the reduction of MMP expression.