Preconditioning Exercise Inhibits Neuron Ferroptosis and Ameliorates Brain Ischemia Damage by Skeletal Muscle-Derived Exosomes via Regulating miR-484/ACSL4 Axis.

Aims: Although there is evidence that patients with stroke who exercise regularly before stroke have a better prognosis than those who do not exercise, the detailed mechanism remains unclear. Moreover, neuronal death plays a central role in neurological dysfunction caused by ischemic stroke. Thus, we investigated whether exercise could reduce stroke-induced neuronal death and its associated mediators in the current study. Results: Ferroptosis was the most dominant form of programmed cell death in neurons. Preconditioning exercise before stroke improved the neurological function and decreased the infarct area in rats with ischemic stroke. Preconditioning exercise attenuated stroke-induced ferroptosis by reducing lipid peroxidation (LPO) production, upregulating glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11 (SLC7A11), and downregulating acyl-CoA synthetase long-chain family member 4 (ACSL4). High-throughput sequencing and dual luciferase reporter assays revealed that exercise-induced exosomal miR-484 inhibits Acsl4 expression. Moreover, we showed that exercise-induced exosomal miR-484 is mainly derived from skeletal muscle, and the neuroprotective effect of preconditioning exercise is suppressed by inhibiting miR-484 production in skeletal muscle. Innovation: This study suggested that neuronal ferroptosis is the most dominant form of programmed cell death in a hypoxic environment. Moreover, we showed that the ferroptosis pathway is a potential therapeutic target in ischemic stroke and that preconditioning exercise could be an effective antioxidant intervention for cerebral ischemia. Conclusion: Our work revealed that preconditioning exercise before stroke exerts neuroprotective effects against brain ischemia by skeletal muscle-derived exosomal miR-484 via inhibiting ferroptosis.

Comparison of Helicobacter pylori positive and negative gastric cancer via multi-omics analysis.

Helicobacter pylori (H. pylori) has been regarded as a definite carcinogenic bacterium for gastric cancer (GC). This multi-omics research was designed to investigate the genetic, microbial, and metabolic changes of GC patients when they are infected with H. pylori. We first mined The Cancer Genome Atlas Stomach Adenocarcinoma (STAD) data to identify the key genes and critical pathways in H. pylori-positive individuals with GC compared to H. pylori-negative individuals with GC. Then, fresh stool samples were collected from GC individuals screened for eligibility, and we analyzed the microbial changes and metabolite alterations between H. pylori-positive and H. pylori-negative GC individuals. Finally, we tried to explore the interaction between key gut flora and metabolite changes in GC patients infected with H. pylori. We identified three genes (GCG, APOA1, and IGFBP1) with significant relevance to H. pylori infection, and the survival monogram based on the three H. pylori-related genes showed good predictive ability for overall survival among GC individuals. 16S rRNA sequencing showed that the abundance of Escherichia-Shigella, Bacteroides, Enterococcus, and Lactobacillus was upregulated in GC cases with H. pylori at the level of genus. There exists a great difference in alpha and beta diversity between H. pylori group and non-H. pylori group. The untargeted metabolome analysis identified 295 significant fecal metabolites, and the levels of penitrem E, auberganol, stercobilinogen, and lys thr are upregulated in the H. pylori group. Finally, correlation analysis showed that there exists a significant correlation between the fecal metabolites and gut bacterial strains. This is the first clinical research to investigate the difference between GC patients with H. pylori and GC patients without H. pylori via multi-omics analysis. 16S rRNA sequencing along with untargeted metabolomics demonstrated decreased microbial diversity and metabolic dysregulation in gastric carcinoma individuals with H. pylori infection.IMPORTANCEThis is the first clinical research to systematically expound the difference between gastric cancer (GC) individuals with Helicobacter pylori and GC individuals without H. pylori from the perspective of multi-omics. This clinical study identified significant genes, microbes, and fecal metabolites, which exhibited nice power for differentiating GC individuals with H. pylori infection from GC individuals without H. pylori infection. This study provides a crucial basis for a better understanding of eradication therapy among the GC population.

Human Olfactory Mesenchymal Stem Cells Are a Novel Candidate for Neurological Autoimmune Disease.

Background: Human olfactory mesenchymal stem cells (OMSC) have become a novel therapeutic option for immune disorder or demyelinating disease due to their immunomodulatory and regenerative potentials. However, the immunomodulatory effects of OMSC still need to be elucidated, and comparisons of the effects of different MSCs are also required in order to select an optimal cell source for further applications. Results: In animal experiments, we found neural functional recovery and delayed EAE attack in the OMSC treatment group. Compared with umbilical cord-derived mesenchymal stem cells (UMSC) treatment group and the control group, the OMSC treatment group had a better neurological improvement, lower serum levels of IFN-γ, and a lower proportion of CD4+IFN-γ+ T splenic lymphocyte. We also observed OMSC effectively suppressed CD4+IFN-γ+ T cell proportion in vitro when co-cultured with human peripheral blood-derived lymphocytes. The OMSC-mediated immunosuppressive effect on human CD4+IFN-γ+ T cells was attenuated by blocking cyclooxygenase activity. Conclusion: Our results suggest that OMSC treatment delayed the onset and promoted the neural functional recovery in the EAE mouse model possibly by suppressing CD4+IFN-γ+ T cells. OMSC transplantation might become an alternative therapeutic option for neurological autoimmune disease.

Correlation of N30 somatosensory evoked potentials with spasticity and neurological function after stroke: A cross-sectional study.

OBJECTIVE: To test whether the presence of N30 somatosensory evoked potentials, generated from the supplementary motor area and premotor cortex, correlate with post-stroke spasticity, motor deficits, or motor recovery stage. DESIGN: A cross-sectional study. PATIENTS: A total of 43 patients with stroke hospitalized at Maoming People's Hospital, Maoming, China. METHODS: Forty-three stroke patients underwent neurofunctional tests, including Modified Ashworth Scale (MAS), Brunnstrom stage, manual muscle test and neurophysiological tests, including N30 somatosensory evoked potentials, N20 somatosensory evoked potentials, motor evoked potentials, H-reflex. The results were compared between groups. Correlation and regression analyses were performed as well. RESULTS: Patients with absence of N30 somatosensory evoked potential exhibited stronger flexor carpi radialis muscle spasticity (r = -0.50, p < 0.05) and worse motor function (r = 0.57, p < 0.05) than patients with presence of N30 somatosensory evoked potential. The generalized linear model (GLM) including both N30 somatosensory evoked potentials and motor evoked potentials (Akaike Information Criterion (AIC) = 121.99) better reflected the recovery stage of the affected proximal upper limb than the models including N30 somatosensory evoked potentials (AIC = 125.06) or motor evoked potentials alone (AIC = 127.45). CONCLUSION: N30 somatosensory evoked potential status correlates with the degrees of spasticity and motor function of stroke patients. The results showed that N30 somatosensory evoked potentials hold promise as a biomarker for the development of spasticity and the recovery of proximal limbs.

Circular RNA circIKBKB promotes breast cancer bone metastasis through sustaining NF-κB/bone remodeling factors signaling.

BACKGROUND: Breast cancer (BC) has a marked tendency to spread to the bone, resulting in significant skeletal complications and mortality. Recently, circular RNAs (circRNAs) have been reported to contribute to cancer initiation and progression. However, the function and mechanism of circRNAs in BC bone metastasis (BC-BM) remain largely unknown. METHODS: Bone-metastatic circRNAs were screened using circRNAs deep sequencing and validated using in situ hybridization in BC tissues with or without bone metastasis. The role of circIKBKB in inducing bone pre-metastatic niche formation and bone metastasis was determined using osteoclastogenesis, immunofluorescence and bone resorption pit assays. The mechanism underlying circIKBKB-mediated activation of NF-κB/bone remodeling factors signaling and EIF4A3-induced circIKBKB were investigated using RNA pull-down, luciferase reporter, chromatin isolation by RNA purification and enzyme-linked immunosorbent assays. RESULTS: We identified that a novel circRNA, circIKBKB, was upregulated significantly in bone-metastatic BC tissues. Overexpressing circIKBKB enhanced the capability of BC cells to induce formation of bone pre-metastatic niche dramatically by promoting osteoclastogenesis in vivo and in vitro. Mechanically, circIKBKB activated NF-κB pathway via promoting IKKß-mediated IκBα phosphorylation, inhibiting IκBα feedback loop and facilitating NF-κB to the promoters of multiple bone remodeling factors. Moreover, EIF4A3, acted acting as a pre-mRNA splicing factor, promoted cyclization of circIKBKB by directly binding to the circIKBKB flanking region. Importantly, treatment with inhibitor eIF4A3-IN-2 reduced circIKBKB expression and inhibited breast cancer bone metastasis effectively. CONCLUSION: We revealed a plausible mechanism for circIKBKB-mediated NF-κB hyperactivation in bone-metastatic BC, which might represent a potential strategy to treat breast cancer bone metastasis.

Bioinformatic Analysis of Exosomal MicroRNAs of Cerebrospinal Fluid in Ischemic Stroke Rats After Physical Exercise.

Physical exercise is beneficial to the structural and functional recovery of post-ischemic stroke, but its molecular mechanism remains obscure. Herein, we aimed to explore the underlying mechanism of exercise-induced neuroprotection from the perspective of microRNAs (miRNAs). Adult male Sprague-Dawley (SD) rats were randomly distributed into 4 groups, i.e., the physical exercise group with the transient middle cerebral artery occlusion (tMCAO) surgery (PE-IS, n = 28); the physical exercise group without tMCAO surgery (PE, n = 6); the sedentary group with tMCAO surgery (Sed-IS, n = 28); and the sedentary group without tMCAO surgery (Sed, n = 6). Notably, rats in the PE-IS and PE groups were subjected to a running exercise for 28 days while rats in the Sed-IS and Sed groups received no exercise training. After long-term exercise, exosomal miRNAs of cerebrospinal fluid (CSF) were analyzed using high-throughput sequencing. Furthermore, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were employed for the differentially expressed miRNAs. Physical exercise improved the neurological function and attenuated the lesion expansion after stroke. In total, 41 differentially expressed miRNAs were screened for the GO and KEGG analysis. GO enriched terms were associated with the central nervous system, including cellular response to retinoic acid, vagus nerve morphogenesis, cellular response to hypoxia, dendritic cell chemotaxis, cell differentiation, and regulation of neuron death. Besides, these differentially expressed miRNAs were linked to the pathophysiological process of stroke, including axon guidance, NF-kappa B signaling pathway, thiamine metabolism, and MAPK signaling pathway according to KEGG analysis. In summary, exercise training significantly alleviated the neurological damage at both functional and structural levels. Moreover, the differentially expressed miRNAs regulating multiple signal pathways were potentially involved in the neuroprotective effects of physical exercise. Therefore, these miRNAs altered by physical exercise might represent the therapeutic strategy for cerebral ischemia.

Effects of Exosomes on Neurological Function Recovery for Ischemic Stroke in Pre-clinical Studies: A Meta-analysis.

Background: Exosomes, especially stem cell-derived exosomes, have been widely studied in pre-clinical research of ischemic stroke. However, their pooled effects remain inconclusive. Methods: Relevant literature concerning the effects of exosomes on neurological performance in a rodent model of ischemic stroke was identified via searching electronic databases, including PubMed, Embase, and Web of Science. The primary outcomes included neurological function scores (NFS) and infarct volume (IV), and the secondary outcomes were several pro-inflammatory factors and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling-positive cells. Subgroup analyses regarding several factors potentially influencing the effects of exosomes on NFS and IV were also conducted. Results: We identified 21 experiments from 18 studies in the meta-analysis. Pooled analyses showed the positive and significant effects of exosomes on NFS (standardized mean difference -2.79; 95% confidence interval -3.81 to -1.76) and IV (standardized mean difference -3.16; 95% confidence interval -4.18 to -2.15). Our data revealed that the effects of exosomes on neurological outcomes in rodent stroke models might be related to routes of administration and exosomes sources. In addition, there was significant attenuation in pro-inflammatory factors, including interleukin-6, tumor necrosis factor-α and interleukin-1ß, and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling-positive cells when undergoing exosomes treatment. Conclusion: Cell-derived exosomes treatment demonstrated statistically significant improvements in structural and neurological function recovery in animal models of ischemic stroke. Our results also provide relatively robust evidence supporting cell-derived exosomes as a promising therapy to promote neurological recovery in stroke individuals.