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摘要: The E3 ubiquitin ligase RNF187, also known as RING domain AP1 coactivator-1, is a member of the RING finger family. RNF187 is indispensable for the proliferation and migration of GC-1 cells derived from mouse spermatogonia and GC-2 cells derived from spermatocytes. However, it remains unclear whether RNF187 plays a crucial role in the self-renewal and migration of human spermatogonial stem cells (SSCs). In this study, we observed a positive correlation between RNF187 expression and the proliferation and migration of human SSCs. Through co-immunoprecipitation and mass spectrometry analyses, we identified WD repeat-containing protein 77 (WDR77) as an interacting partner of RNF187. Specifically, RNF187 recognises the K118 site of WDR77 through lysine 48-linked polyubiquitination, subsequently mediating its degradation via the ubiquitin-proteasome system (UPS). Further studies have revealed that decreased expression of WDR77 diminishes the symmetric dimethylation at H4R3 (H4R3me2s) catalysed by its interacting protein, the arginine methyltransferase PRMT5. This, in turn, relieves the transcriptional repression of early growth response protein 1 (EGR1), a positive regulator for human SSC maintenance. In conclusion, this study has unveiled a pivotal role for RNF187 in the proliferation and migration of human SSCs. This may provide a promising strategy for addressing non-obstructive azoospermia (NOA) caused by SSC dysfunction.

摘要: Osteoarthritis (OA) is a prevalent and debilitating joint disorder that affects millions of individuals worldwide, severely impairing mobility, independence, and quality of life. Emerging evidence suggests that ferroptosis is a critical factor in OA pathogenesis. However, its precise involvement and underlying mechanisms remain poorly understood. In this study, we first identified that cartilage intermediate layer protein (CILP) mediates the regulation of ferroptosis-related genes in OA through hdWGCNA analysis combined with single-cell RNA sequencing. Further investigation revealed a significant upregulation of CILP protein expression in C28/I2 cells under LPS induction. Mechanistically, bioinformatics analysis identified differentially expressed miRNAs; qRT-PCR combined with a dual-luciferase experiment revealed that miR-140-3p was downregulated and directly targets CILP. Experimental data further demonstrated that miR-140-3p regulates ferroptosis, inflammation, and oxidative stress by targeting CILP. These findings offer valuable insights into the molecular mechanisms of the miR-140-3p/CILP axis in regulating ferroptosis, inflammation, and oxidative stress, thus providing a foundation for developing therapeutic strategies for OA.

摘要: GPR119 agonists are being developed to safeguard the function of pancreatic beta-cells, especially in the context of non-alcoholic fatty pancreas disease (NAFPD) that is closely associated with beta-cell dysfunction. This study aims to employ a drug repurposing strategy to screen GPR119 agonists and explore their potential molecular mechanisms for enhancing beta-cell function in the context of NAFPD. MIN6 cells were stimulated with palmitic acid (PA), and a NAFPD model was established in GPR119-/- mice fed with a high-fat diet (HFD). Terazosin, identified through screening, was utilized to assess its impact on enhancing beta-cell function via the MST1-Foxo3a pathway and mitophagy. Terazosin selectively activated GPR119, leading to increased cAMP and ATP synthesis, consequently enhancing insulin secretion. Terazosin administration improved high blood glucose, obesity, and impaired pancreatic beta-cell function in NAFPD mice. It inhibited the upregulation of MST1-Foxo3a expression in pancreatic tissue and enhanced damaged mitophagy clearance, restoring autophagic flux, and improving mitochondrial quantity and structure in beta-cells. Nevertheless, GPR119 deficiency negated the positive impact of terazosin on pancreatic beta-cell function in NAFPD mice and abolished its inhibitory effect on the MST1-Foxo3a pathway. Terazosin activates GPR119 on the surface of pancreatic beta-cells, enhancing mitophagy and alleviating beta-cell dysfunction in the context of NAFPD by suppressing the MST1-Foxo3a signalling pathway. Terazosin could be considered a priority treatment for patients with concomitant NAFPD and hypertension.

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摘要: Aerobic glycolysis is involved in the pathogenesis of pulmonary hypertension (PH). The mechanisms by which glycolysis is increased and how it contributes to pulmonary vascular remodelling are not yet fully understood. In this study, we demonstrated that elevated lipocalin-2 (LCN2) in PH significantly enhances aerobic glycolysis in human pulmonary artery smooth muscle cells (PASMCs) by up-regulating LDHA expression. Knockout of Lcn2 or having heterozygous LDHA deficiency in mice significantly inhibits the progression of hypoxic PH. Our study reveals that LCN2 stimulates LDHA expression by activating Akt-HIF-1 alpha signalling pathway. Inhibition of Akt or HIF-1 alpha reduces LDHA expression and proliferation of PASMCs. Both Akt and HIF-1 alpha play critical roles in the development of PH and are suppressed in the pulmonary vessels of hypoxic PH mice lacking LCN2. These findings shed light on the LCN2-Akt-HIF1 alpha-LDHA axis in aerobic glycolysis in PH. Knockout of lipocalin-2 (LCN2) suppresses Akt phosphorylation, HIF-1 alpha and LDHA expression, and pulmonary hypertension (PH) progression. Heterozygous LDHA deficiency suppresses PH progression. LCN2 promotes LDHA expression by activating Akt-HIF-1 alpha signalling axis. LCN2-Akt-HIF-1 alpha-LDHA axis is a potential target for PH treatment. Up-regulated LCN2 promotes LDHA expression and aerobic glycolysis via activation of Akt-HIF-1 alpha signalling, facilitating the metabolic abnormalities and pulmonary artery smooth cell proliferation in pulmonary hypertension. image

摘要: Secondary atrophic rhinitis (AR), a consequence of mucosal damage during nasal surgeries, significantly impairs patient quality of life. The lack of effective, lasting treatments underscores the need for alternative therapeutic strategies. A major impediment in advancing research is the scarcity of studies focused on secondary AR. Our study addresses this gap by developing an animal model that closely mirrors the histopathological changes observed in patients with secondary AR. These changes include squamous metaplasia, goblet cell hyperplasia, submucosal fibrosis, and glandular atrophy. Upon administering human nasal turbinate stem cells embedded in collagen type I hydrogel in these models, we observed ciliary regeneration. This finding suggests the potential therapeutic benefit of this approach. Our animal models not only emulate the clinical manifestations of secondary AR but also serve as valuable tools for evaluating the efficacy of cell-based biotechnological interventions. Tissue specific stem cell therapy on an electrocautery-induced secondary atrophic rhinitis model. image

摘要: Glioblastoma (GBM), a WHO grade IV glioma, is a malignant primary brain tumour for which combination of surgery, chemotherapy and radiotherapy is the first-line approach despite adverse effects. Tumour microenvironment (TME) is characterized by an interplay of cells and soluble factors holding a critical role in neoplastic development. Significant pathophysiological changes have been found in GBM TME, such as glia activation and oxidative stress. Microglia play a crucial role in favouring GBM growth, representing target cells of immune escape mechanisms. Our study aims at analysing radiation-induced effects in modulating intercellular communication and identifying the basis of protective mechanisms in radiation-naive GBM cells. Tumour cells were treated with conditioned media (CM) derived from 0, 2 or 15 Gy irradiated GBM cells or 0, 2 or 15 Gy irradiated human microglia. We demonstrated that irradiated microglia promote an increase of GBM cell lines proliferation through paracrine signalling. On the contrary, irradiated GBM-derived CM affect viability, triggering cell death mechanisms. In addition, we investigated whether these processes involve mitochondrial mass, fitness and oxidative phosphorylation and how GBM cells respond at these induced alterations. Our study suggests that off-target radiotherapy modulates microglia to support GBM proliferation and induce metabolic modifications. Radiotherapy-induced effects, especially in whole brain irradiation, involve both tumour and surrounding healthy cells. Irradiated tumour and microglia cells create a complex network of intercellular communication. Our data reveal that off-target irradiated microglia increase GBM viability, proliferation and growth, sustaining GBM mitochondrial fitness. Irradiated microglia-mediated effects on GBM intracellular context result in a stimulation of oxidative phosphorylation mechanism and an increased protection from mitochondrial oxidative stress. Metformin administration inhibits the pro-tumoural effects mediated by microglial cells on GBM, blocking oxidative phosphorylation metabolic process. image

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摘要: Chronic obstructive pulmonary disease (COPD) is characterised by chronic inflammation and senescence. Previous studies showed that club cells and club cell secretory proteins (CCSP) have anti-inflammatory roles, which reduced in COPD. Klotho (KL) decreased in human COPD lung tissue. KL-deficient mice showed aging phenotypes, such as obvious emphysema and premature senility at the early stage, which are characteristics of COPD. However, little is known about the relationship between KL, club cells, and COPD. We speculated lack of KL would aggravate club cell senescence, which contributes to COPD inflammation. We collected COPD lung tissue using single-cell RNA sequencing (scRNA-seq), revealing club cells heterogeneity and cellular senescence in COPD. In addition, KL and CCSP expressions were downregulated in cigarette smoke (CS)-induced COPD mice, associated with increasing age-related markers. After KL knockout, more ciliated cells appeared where club cells disappeared. Furthermore, KL deficiency aggravated club cell senescence and CSE-induced pulmonary inflammation. To investigate the specific regulation mechanism, hnRNPA2/B1 was recognised and identified it was the key molecule in KL-regulated club cell senescence, and neddylation of club cell was a crucial factor contributing to hnRNPA2/B1 downregulation. In vitro, SA-beta-gal staining suggested the aging phenotype was aggravated in hnRNPA2/B1-silenced groups, and hnRNPA2/B1 over-expressed achieved a rescue result. Thus, KL could regulate club cell senescence and differentiation. When CS stimulates the small airway epithelium, KL deficiency aggravates lung inflammation, club cell senescence and dysfunctional of ciliated cell. Targeting neddylation might be a promising strategy to reverse lung aging and club cell senescence. These results provide a mechanism about COPD-linked lung inflammation.