JOURNAL OF CELLULAR AND MOLECULAR MEDICINE最新文献

Intervertebral disc degeneration (IVDD) is a leading cause of chronic low back pain, yet its cellular and molecular mechanisms remain incompletely understood. Sheep represent a valuable in vivo and ex vivo model for IVDD due to their anatomical and biomechanical similarities with humans and the possibility to access disc samples at early stages of degeneration. In vitro, isolated annulus fibrosus (AF) and nucleus pulposus (NP) cells may provide insights into age-associated degenerative processes; this work investigates how well they capture senescence and metabolic alterations observed in vivo. Transcriptomic profiling of AF and NP cells from healthy young lambs and mildly degenerated aged sheep revealed distinct age- and tissue-specific signatures, with upregulation of inflammatory mediators, ECM-remodelling enzymes, and senescence-associated genes in aged cells. Cross-species deconvolution using a human single-cell RNA-sequencing reference confirmed conserved transcriptional modules between aged sheep and human degenerated discs, underscoring the model's translational relevance. However, functional assays demonstrated comparable responses of young and aged cells under basal conditions and after exposure to pro-degenerative stressors (IL-1β, senescence induction). Altogether, these findings validate sheep cells as a suitable in vitro model for studying disc degeneration mechanisms and for preclinical testing, although aged donors offer no clear additional functional benefits.

Su W, Tang J, Wang Y, Sun S, Shen Y, Yang H. “Long Non-Coding RNA Highly Up-Regulated in Liver Cancer Promotes Epithelial-to-Mesenchymal Transition Process in Oral Squamous Cell Carcinoma,” Journal of Cellular and Molecular Medicine (2019) 23(4):2645–2655, https://doi.org/10.1111/jcmm.14160.

Metabolic dysfunction-associated steatohepatitis (MASH) is a leading cause of liver-related morbidity driven by systemic metabolic dysregulation. The recent approval of resmetirom and the clinical success of GLP-1 receptor agonists have heralded a new era in MASH therapy, yet a convergent understanding of the complex mechanisms of these diverse agents is lacking. This review proposes a mechanistic framework centred on the convergent signalling of AMP-activated protein kinase (AMPK), a master regulator of hepatic energy homeostasis. We examine key metabolism-based therapeutics—pioglitazone, GLP-1 receptor agonists, SGLT2 inhibitors, resmetirom and statins—to delineate how distinct upstream triggers converge on AMPK. Synthesising the latest evidence, we clearly delineate how each drug class activates AMPK either indirectly—through systemic effects like weight loss and glycemic control—or via direct actions on hepatocytes. We specifically contrast the liver-targeted action of resmetirom with the predominantly systemic effects of semaglutide and discuss the ‘epigenetic lock-in’ hypothesis, wherein chronic metabolic stress perpetuates the disease state. Based on this framework, we propose rational strategies for combination therapy. In conclusion, this AMPK-centric framework provides a novel lens for understanding the complex pharmacology of MASH drugs and offers a valuable clinical roadmap for personalising treatment strategies to individual patient phenotypes.

Tubular atrophy and interstitial fibrosis are basic renal pathological changes in autosomal dominant tubulointerstitial kidney disease (ADTKD). Reduced secretion or abnormal structure of uromodulin (UMOD) are recognised pathogenic factors of ADTKD. Studies show uromodulin binds complement factor H (cFH), enhancing its ability to inhibit complement activation. Overactivation of the complement system contributes to tubulointerstitial injury. Therefore, exploring the UMOD–tubulointerstitial fibrosis link may aid in the development of treatment for ADTKD-UMOD. Immunofluorescence staining detected complement deposition in patients' kidneys. Uromodulin's binding affinity for cFH was assessed using microthermophoresis. The effect of this binding on cFH function was analysed using C3b degradation and erythrocyte hemolysis tests. Recombinant wild-type and mutant uromodulin proteins were expressed and tested using the aforementioned methods. Complement factor B was detected in the kidneys of patients with ADTKD-UMOD. Patient-derived uromodulin showed reduced binding to cFH and decreased capacity to assist in C3b cleavage and hemolysis inhibition. Recombinant wild-type uromodulin significantly enhanced C3b cleavage (p < 0.001) and inhibited hemolysis (p < 0.01). Uromodulin mutants showed reduced binding to cFH and limited ability to promote C3b degradation, with no significant hemolysis inhibition. Impaired interactions between mutants and cFH may lead to insufficient inhibition of complement activity, triggering tubulointerstitial fibrosis.

Perioperative neurocognitive disorder (PND) is a common complication after anesthesia surgery in elderly patients, which not only reduces the patients' quality of life but also increases the burden on their families and society. PND has been found to be closely related to ferroptosis. This study investigated whether electroacupuncture (EA) can inhibit ferroptosis through the SIRT1/NRF2/GPX4 pathway to improve PND in aged mice. The PND model was established using sevoflurane anesthesia and tibial fracture surgery. EA was administered at the Baihui (GV 20) and Dazhui (GV 14) acupoints. Additionally, intraperitoneal injection of silent information regulator sirtuin 1 (SIRT1) inhibitor EX527 (5 mg/kg) was administered for five consecutive days before surgery and intraperitoneal injection of ferrostatin-1 (Fer-1) (2 mg/kg) was administered before anesthesia. On the third day after surgery, the cognitive ability of the aged mice was measured using the Y-maze, and motor ability was assessed by total distance in the open field test. Transmission electron microscopy was used to observe hippocampal mitochondrial structure. Immunofluorescence staining was used to detect glutathione peroxidase 4 (GPX4) levels in the hippocampus. Flow cytometry measured ATP content and mitochondrial membrane potential in hippocampal mitochondria. A colorimetric assay was used to detect iron content in hippocampal neurons. Reverse transcription-quantitative polymerase chain reaction and Western blotting were used to detect mRNA and protein expression of Solute carrier family 7 member (SLC7A11), transferrin receptor 1 (TFR1), iron regulatory protein 2 (IRP2), ferritin, SIRT1, nuclear factor erythroid 2-related factor 2 (NRF2) and GPX4. The results showed that compared with the model group, the EA treatment group and the Fer-1 (iron inhibitor) treatment group revealed improved ferroptosis and memory function in hippocampal neurons, while the EX527 (SIRT1 inhibitor) treatment group did not reveal any improvement. In conclusion, the occurrence and progression of PND are closely related to ferroptosis. EA stimulation of the Baihui and Dazhui acupoints can improve PND, possibly by regulating ferroptosis through the SIRT1/NRF2/GPX4 signalling pathway.

The conserved aspartic acid residue D661 within the STAT3 SH2 domain is a recurrent mutational hotspot in hematologic malignancies, including T-cell large granular lymphocytic leukaemia, myelodysplastic syndromes and acute lymphoblastic leukaemia. To define the functional consequences of distinct STAT3^D661 variants, we integrated computational, structural and in vitro and in vivo genetic approaches. AlphaMissense and PolyPhen-2 classified all four STAT3^D661 variants (D661Y, D661V, D661N and D661H) as pathogenic. ClinVar classified D661Y and D661V as variants of uncertain significance. AlphaFold 3-based modelling predicted that D661Y and D661V strongly promoted SH2-TAD-mediated dimerization, while D661N and D661H exerted weaker structural effects. Functional in vitro assays in Stat3-deficient T cells demonstrated a gain-of-function (GOF) hierarchy of the STAT3 variants (D661Y ≈ V > H > N) resulting in activation of canonical STAT3 target genes and immune transcriptional programs. In vivo, only STAT3^D661H mice were viable, displaying reduced CD4⁺ T cells, expansion of memory CD8⁺ T cells and enhanced immune gene expression. Collectively, our findings define a gradient of STAT3 D661 GOF variants, consistent with in vitro and in vivo experiments. D661Y and D661V mutants exhibited stronger transcriptional activity in T cells with impaired viability of mice carrying these variants.

Tumour immunotherapy targeting PD-1/PD-L1 shows promise, but the regulatory mechanisms of PD-L1 and its small-molecule modulators remain unclear. This study investigated FoxO3a-mediated PD-L1 regulation and the PD-L1-inhibitory role of dihydroartemisinin (DA) in triple-negative breast cancer (TNBC). FoxO3a overexpression significantly increased PD-L1 expression and impaired T cell-mediated cytotoxicity, while knockdown exerted opposite effects in TNBC cells. Promoter motif analysis and dual-luciferase assays revealed FoxO3a binding to the s155 site on the PD-L1 promoter in MDA-MB-231 cells; mutation of s155 abolished this interaction. ChIP-PCR confirmed FoxO3a binding to the PD-L1 promoter at s155. Furthermore, DA, a clinical antimalarial, reduced PD-L1 and FoxO3a levels, sensitising TNBC cells to T cell killing in TNBC cells. Mechanistically, DA enhanced IRE1/IKK phosphorylation, promoting FoxO3a Ser644 phosphorylation and ubiquitination. Crucially, s155 was required for DA-induced PD-L1 suppression in MDA-MB-231 cells. These findings demonstrate PD-L1 as a direct transcriptional target of FoxO3a and identify DA as a potential TNBC therapeutic targeting the IRE1/IKK/FoxO3a/PD-L1 axis.

Tripartite motif 52 (TRIM52) has been identified as a key regulator of inflammatory responses. However, its involvement in doxorubicin (DOX)-induced cardiotoxicity (DIC) and the underlying molecular mechanisms remain poorly understood. To investigate the functional role of TRIM52, we employed an adeno-associated virus serotype 9 (AAV9) delivery system to achieve cardiac-specific Trim52 knockout via tail-vein injection. C57BL/6 mice received intraperitoneal DOX (5 mg/kg, administered once a week, with a total cumulative dose of 15 mg/kg). Myocardial injury was evaluated by histopathological assessment and molecular profiling of cardiac tissues, complemented by in vitro mechanistic studies using neonatal mouse cardiomyocytes. In vivo and in vitro studies revealed that DOX treatment significantly upregulated TRIM52 expression. Trim52 deficiency effectively mitigated DOX-induced cardiac injury and dysfunction, concomitantly attenuating oxidative stress and inflammatory responses. Mechanistically, Trim52 deletion markedly enhanced PI3K and AKT phosphorylation, indicating that PI3K/AKT pathway activation underlies the cardioprotective effects of TRIM52 deficiency. Our findings demonstrate that TRIM52 deletion activates PI3K/AKT signalling and attenuates DOX-induced oxidative and inflammatory myocardial damage. These data identify TRIM52 as a potential therapeutic target for mitigating DIC.