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Abstract The maintenance of hematopoietic stem cell (HSC) functional integrity is essential for effective hematopoietic regeneration when suffering from injuries. Studies have shown that the innate immune pathways play crucial roles in the stress response of HSCs, whereas how to precisely modulate these pathways is not well characterized. Here, we identify the E3 ubiquitin ligase tripartite motif-containing 47 (Trim47) as a negative regulator of the mitochondrial antiviral-signaling protein (MAVS)-mediated innate immune pathway in HSCs. We find that Trim47 is predominantly enriched in HSCs, and its deficiency impairs the function and survival of HSCs after exposure to 5-flurouracil (5-FU) and irradiation (IR). Mechanistically, Trim47 impedes the excessive activation of the innate immune signaling and inflammatory response via K48-linked ubiquitination and degradation of MAVS. Collectively, our findings demonstrate a role of Trim47 in preventing stress-induced hematopoietic failure and thus provide a promising avenue for treatment of related diseases in the clinic.

Abstract Background The relationship between variation in serum uric acid (SUA) levels and brain health is largely unknown. This study aimed to examine the associations of long-term variability in SUA levels with neuroimaging metrics and cognitive function. Methods This study recruited 1111 participants aged 25–83 years from a multicenter, community-based cohort study. The SUA concentrations were measured every two years from 2006 to 2018. We measured the intraindividual SUA variability, including the direction and magnitude of change by calculating the slope value. The associations of SUA variability with neuroimaging markers (brain macrostructural volume, microstructural integrity, white matter hyperintensity, and the presence of cerebral small vessel disease) and cognitive function were examined using generalized linear models. Mediation analyses were performed to assess whether neuroimaging markers mediate the relationship between SUA variation and cognitive function. Results Compared with the stable group, subjects with increased or decreased SUA levels were all featured by smaller brain white matter volume (beta = − 0.25, 95% confidence interval [CI] − 0.39 to − 0.11 and beta = − 0.15, 95% CI − 0.29 to − 0.02). Participants with progressively increased SUA exhibited widespread disrupted microstructural integrity, featured by lower global fractional anisotropy (beta = − 0.24, 95% CI − 0.38 to − 0.10), higher mean diffusivity (beta = 0.16, 95% CI 0.04 to 0.28) and radial diffusivity (beta = 0.19, 95% CI 0.06 to 0.31). Elevated SUA was also associated with cognitive decline (beta = − 0.18, 95% CI − 0.32 to − 0.04). White matter atrophy and impaired brain microstructural integrity mediated the impact of SUA increase on cognitive decline. Conclusions It is the magnitude of SUA variation rather than the direction that plays a critical negative role in brain health, especially for participants with hyperuricemia. Smaller brain white matter volume and impaired microstructural integrity mediate the relationship between increased SUA level and cognitive function decline. Long-term stability of SUA level is recommended for maintaining brain health and preventing cognitive decline.

Immunoglobulin 4-related disease (IgG4-RD) is known for its potential to affect nearly every organ, particularly a preference for large and middle-sized arteries when vascular involvement occurs. However, instances of splenic artery aneurysms are exceedingly rare with only two cases reported in the literature. We have summarised the clinical manifestations and laboratory characteristics of the three patients we reported along with the two patients previously reported. It is noteworthy that all five patients had involvement of the salivary glands and only one patient had other arterial involvement. The three patients we reported had no new organ onset or worsening of existing organ involvement and normal or not significantly elevated serum IgG4 levels when the artery aneurysm was identified. These aneurysms may be the result of vascular damage from prior involvement that was not recognised previously. The cases we reported here highlight a potential association between IgG4-RD and concurrent splenic artery aneurysms.

The hematopoietic system is susceptible to ionizing radiation (IR), which can cause acute hematopoietic failure or long-term myelosuppression. As the most primitive cells of the hematopoietic hierarchy, hematopoietic stem cells (HSCs) maintain lifelong hematopoietic homeostasis and promote hematopoietic regeneration during stress. Numerous studies have shown that nuclear and mitochondrial genomes are the main targets of radiation injury in HSCs. More importantly, the damage of DNA may trigger a series of biological responses that largely determine HSC fate following IR exposure. Although some essential pathways and factors involved in DNA injury and damage in HSCs have been revealed, a comprehensive understanding of the biological effects of radiation on HSCs still needs to be improved. This review focuses on recent insights into the molecular mechanisms underlying DNA damage and repair in HSCs after IR. Then summarize corresponding regulatory measures, which may provide a reference for further research in this field.

Aims: The xanthone dimer 12-O-deacetyl-phomoxanthone A (12-ODPXA) was extracted from the secondary metabolites of the endophytic fungus Diaporthe goulteri. The 12-ODPXA compound exhibited anticancer properties in murine lymphoma; however, the anti-ovarian cancer (OC) mechanism has not yet been explored. Therefore, the present study evaluated whether 12-ODPXA reduces OC cell proliferation, metastasis, and invasion by downregulating pyruvate dehydrogenase kinase (PDK)4 expression. Methods: Cell counting kit-8, colony formation, flow cytometry, wound healing, and transwell assays were performed to examine the effects of 12-ODPXA on OC cell proliferation, apoptosis, migration, and invasion. Transcriptome analysis was used to predict the changes in gene expression. Protein expression was determined using western blotting. Glucose, lactate, and adenosine triphosphate (ATP) test kits were used to measure glucose consumption and lactate and ATP production, respectively. Zebrafish xenograft models were constructed to elucidate the anti-OC effects of 12-ODPXA. Results: The 12-ODPXA compound inhibited OC cell proliferation, migration, invasion, and glycolysis while inducing cell apoptosis via downregulation of PDK4. In vivo experiments showed that 12-ODPXA suppressed tumor growth and migration in zebrafish. Conclusion: Our data demonstrate that 12-ODPXA inhibits ovarian tumor growth and metastasis by downregulating PDK4, revealing the underlying mechanisms of action of 12-ODPXA in OC.

Ferroptosis has emerged as a potential mechanism for enhancing the efficacy of chemotherapy in cancer treatment. By suppressing nuclear factor erythroid 2-related factor 2 (Nrf2), cancer cells may lose their ability to counteract the oxidative stress induced by chemotherapy, thereby becoming more susceptible to ferroptosis. In this study, we investigate the potential of penexanthone A (PXA), a xanthone dimer component derived from the endophytic fungus Diaporthe goulteri, obtained from mangrove plant Acanthus ilicifolius, to enhance the therapeutic effect of cisplatin (CDDP) on colorectal cancer (CRC) by inhibiting Nrf2. The present study reported that PXA significantly improved the ability of CDDP to inhibit the activity of and induce apoptosis in CRC cells. Moreover, PXA was found to increase the level of oxidative stress and DNA damage caused by CDDP. In addition, the overexpression of Nrf2 reversed the DNA damage and ferroptosis induced by the combination of PXA and CDDP. In vivo experiments using zebrafish xenograft models demonstrated that PXA enhanced the therapeutic effect of CDDP on CRC. These studies suggest that PXA enhanced the sensitivity of CRC to CDDP and induce ferroptosis by targeting Nrf2 inhibition, indicating that PXA might serve as a novel anticancer drug in combination chemotherapy.