Translational Research最新文献

Cardiac fibrosis under chronic pressure overload is an end-stage adverse remodeling of heart. However, current heart failure treatments barely focus on anti-fibrosis and the effects are limited. We aimed to seek for a cardiac abundant and cardiac fibrosis specific piRNA, exploring its underlying mechanism and therapeutic potential. Whole transcriptome sequencing and the following verification experiments identified a highly upregulated piRNA (piRNA-000691) in transverse aortic constriction (TAC) mice, TAC pig, and heart failure human samples, which was abundant in heart and specifically expressed in cardiac fibroblasts. CFRPi was gradually increased along with the progression of heart failure, which was illustrated to promote cardiac fibrosis by gain- and loss-of-function experiments in vitro and in vivo. Knockdown of CFRPi in mice alleviated cardiac fibrosis, reversed decline of systolic and diastolic functions from TAC 6 weeks to 8 weeks. Mechanistically, CFRPi inhibited APLN, a protective peptide that increased in early response and became exhausted at late stage. Knockdown of APLN in vitro notably aggravated cardiac fibroblasts activation and proliferation. In vitro and in vivo evidence both indicated Pi3k-AKT-mTOR as the downstream effector pathway of CFRPi-APLN interaction. Collectively, we here identified CFPPi as a heart abundant and cardiac fibrosis specific piRNA. Targeting CFRPi resulted in a sustainable increase of APLN and showed promising therapeutical prospect to alleviate fibrosis, rescue late-stage cardiac dysfunction, and prevent heart failure.

Inflammation is a crucial pathophysiological mechanism in atherosclerosis (AS). This study aims to investigate the impact of sulfotransferase family 2b member 1 (SULT2B1) on the inflammatory response of macrophages and the progression of AS. Here, we reported that SULT2B1 expression increased with the progression of AS. In AS model mice, knockdown of Sult2b1 led to remission of AS and reduced inflammation levels. Further exploration of the downstream molecular mechanisms of SULT2B1 revealed that suppressing Sult2b1 in macrophages resulted in decreased levels of 25HC3S in the nucleus, elevated expression of Lxr, and increased the transcription of Lncgga3-204. In vivo, knockdown of Lncgga3-204 aggravated the inflammatory response and AS progression, while the simultaneous knockdown of both Sult2b1 and Lncgga3-204 exacerbated AS and the inflammatory response compared with knockdown of Sult2b1 alone. Increased binding of Lncgga3-204 to SMAD4 in response to oxidized-low density lipoprotein (ox-LDL) stimulation facilitated SMAD4 entry into the nucleus and regulated Smad7 transcription, which elevated SMAD7 expression, suppressed NF-κB entry into the nucleus, and ultimately attenuated the macrophage inflammatory response. Finally, we identified the presence of a single nucleotide polymorphism (SNP), rs2665580, in the SULT2B1 promoter region in monocytes from coronary artery disease (CAD) patients. The predominant GG/AG/AA genotypes were observed in the Asian population. Elevated SULT2B1 expression in monocytes with GG corresponded to elevated inflammatory factor levels and more unstable coronary plaques. To summarize, our study demonstrated that the critical role of SULT2B1/Lncgga3-204/SMAD4/NF-κB in AS progression. SULT2B1 serves as a novel biomarker indicating inflammatory status, thereby offering insights into potential therapeutic strategies for AS.

Tyrosine kinase inhibitors (TKIs) are frequently utilized in the management of malignant tumors. Studies have indicated that anlotinib has a significant inhibitory effect on oral squamous cell carcinoma (OSCC). However, the mechanisms underlying the development of resistance with long-term anlotinib treatment remain obscure. Our research found that METTL1 expression was heightened in anlotinib-resistant OSCC cells. We observed that METTL1 played a role in fostering resistance to anlotinib in both transgenic mouse models and in vitro. Mechanistically, the elevated METTL1 levels in anlotinib-resistant OSCC cells contributed to enhanced global mRNA translation and stimulated oxidative phosphorylation (OXPHOS) through m7G tRNA modification. Bioenergetic profiling demonstrated that METTL1 drived a metabolic shift from glycolysis to OXPHOS in anlotinib-resistant OSCC cells. Additionally, inhibition of OXPHOS biochemically negated METTL1′s impact on anlotinib resistance. Overall, this study underscores the pivotal role of METTL1-mediated m7G tRNA modification in anlotinib resistance and lays the groundwork for novel therapeutic interventions to counteract resistance in OSCC.

Cardiovascular disease and heart failure doubles in patients with chronic kidney disease (CKD), but the underlying mechanisms remain obscure. Mitochondria are central to maintaining cellular respiration and modulating cardiomyocyte function. We took advantage of our novel swine model of CKD and left ventricular diastolic dysfunction (CKD-LVDD) to investigate the expression of mitochondria-related genes and potential mechanisms regulating their expression. CKD-LVDD and normal control pigs (n=6/group, 3 males/3 females) were studied for 14 weeks. Renal and cardiac hemodynamics were quantified by multidetector-CT, echocardiography, and pressure-volume loop studies, respectively. Mitochondrial morphology (electron microscopy) and function (Oroboros) were assessed ex vivo. In randomly selected pigs (n=3/group), cardiac mRNA-, MeDIP-, and miRNA-sequencing (seq) were performed to identify mitochondria-related genes and study their pre- and post -transcriptional regulation. CKD-LVDD exhibited cardiac mitochondrial structural abnormalities and elevated mitochondrial H2O2 emission but preserved mitochondrial function. Cardiac mRNA-seq identified 862 mitochondria-related genes, of which 69 were upregulated and 33 downregulated (fold-change ≥2, false discovery rate≤0.05). Functional analysis showed that upregulated genes were primarily implicated in processes associated with oxidative stress, whereas those downregulated mainly participated in respiration and ATP synthesis. Integrated mRNA/miRNA/MeDIP-seq analysis showed that upregulated genes were modulated predominantly by miRNAs, whereas those downregulated were by miRNA and epigenetic mechanisms. CKD-LVDD alters cardiac expression of mitochondria-related genes, associated with mitochondrial structural damage but preserved respiratory function, possibly reflecting intrinsic compensatory mechanisms. Our findings may guide the development of early interventions at stages of cardiac dysfunction in which mitochondrial injury could be prevented, and the development of LVDD ameliorated.

Prolonged sevoflurane anesthesia is the primary factor contributing to the development of perioperative neurocognitive disorders (PND). Recent studies have highlighted neuronal apoptosis and abnormal dendritic structures as crucial features of PND. Astrocytes-derived exosomes (ADEs) have been identified as carriers of microRNAs (miRNAs), playing a vital role in cell-to-cell communication through transmitting genetic material. Nevertheless, the specific mechanisms by which miRNAs in ADEs contribute to sevoflurane-induced cognitive deficit are currently unknown. Through a series of in vivo and in vitro experiments, we demonstrated that ADEs contributed to improved neurocognitive outcomes by reducing neuronal apoptosis and promoting dendritic development. Our miRNA microarray analysis revealed a significant increase in the expression level of miR-26a-5p within ADEs. Furthermore, we identified NCAM as the downstream target gene of miR-26a-5p. Subsequent gain- and loss-of-function experiments were conducted to validate the role of the miR-26a-5p/NCAM axis. Finally, we found that the AKT/GSK3-β/CRMP2 signaling pathway was involved in regulating neurons through exosomal miR-26a-5p. Taken together, our findings suggest that the treatment with miR-26a-5p in ADEs can improve neurocognitive outcomes induced by long-term sevoflurane anesthesia, suggesting a promising approach for retarding the progress of PND.

Traumatic brain injury (TBI) has a significant impact on cognitive function, affecting millions of people worldwide. Myelin loss is a prominent pathological feature of TBI, while well-functioning myelin is crucial for memory and cognition. Utilizing drug repurposing to identify effective drug candidates for TBI treatment has gained attention. Notably, recent research has highlighted the potential of clemastine, an FDA-approved allergy medication, as a promising pro-myelinating drug. Therefore, in this study, we aim to investigate whether clemastine can enhance myelination and alleviate cognitive impairment following mild TBI using a clinically relevant rat model of TBI. Mild diffuse TBI was induced using the Closed-Head Impact Model of Engineered Rotational Acceleration (CHIMERA). Animals were treated with either clemastine or an equivalent volume of the vehicle from day 1 to day 14 post-injury. Following treatment, memory-related behavioral tests were conducted, and myelin pathology in the cortex and hippocampus was assessed through immunofluorescence staining and ProteinSimple® capillary-based immunoassay. Our results showed that TBI leads to significant myelin loss, axonal damage, glial activation, and a decrease in mature oligodendrocytes in both the cortex and hippocampus. The TBI animals also exhibited notable deficits in memory-related tests. In contrast, animals treated with clemastine showed an increase in mature oligodendrocytes, enhanced myelination, and improved performance in the behavioral tests. These preliminary findings support the therapeutic value of clemastine in alleviating TBI-induced cognitive impairment, with substantial clinical translational potential. Our findings also underscore the potential of remyelinating therapies for TBI.

Interleukin (IL)-33, a cytokine involved in immune responses, can activate its receptor, suppression of tumorigenicity 2 (ST2), is elevated during atrial fibrillation (AF). However, the role of IL-33/ST2 signaling in atrial arrhythmia is unclear. This study explored the pathological effects of the IL-33/ST2 axis on atrial remodeling and arrhythmogenesis. Patch clamping, confocal microscopy, and Western blotting were used to analyze the electrical characteristics of and protein activity in atrial myocytes (HL-1) treated with recombinant IL-33 protein and/or ST2-neutralizing antibodies for 48 hrs. Telemetric electrocardiographic recordings, Masson's trichrome staining, and immunohistochemistry staining of the atrium were performed in mice receiving tail vein injections with nonspecific immunoglobulin (control), IL-33, and IL-33 combined with anti-ST2 antibody for 2 weeks. IL-33-treated HL-1 cells had a reduced action potential duration, lower L-type Ca²⁺ current, greater sarcoplasmic reticulum (SR) Ca²⁺ content, increased Na⁺/Ca²⁺ exchanger (NCX) current, elevation of K⁺ currents, and increased intracellular calcium transient. IL-33-treated HL-1 myocytes had greater activation of the calcium–calmodulin-dependent protein kinase II (CaMKII)/ryanodine receptor 2 (RyR2) axis and nuclear factor kappa B (NF-κB) / NLR family pyrin domain containing 3 (NLRP3) signaling than did control cells. IL-33 treated cells also had greater expression of Nav1.5, Kv1.5, NCX, and NLRP3 than did control cells. Pretreatment with neutralizing anti-ST2 antibody attenuated IL-33-mediated activation of CaMKII/RyR2 and NF-κB/NLRP3 signaling. IL-33-injected mice had more atrial ectopic beats and increased AF episodes, greater atrial fibrosis, and elevation of NF-κB/NLRP3 signaling than did controls or mice treated with IL-33 combined with anti-ST2 antibody. Thus, IL-33 recombinant protein treatment promotes atrial remodeling through ST2 signaling. Blocking the IL-33/ST2 axis might be an innovative therapeutic approach for patients with atrial arrhythmia and elevated serum IL-33.

Due to soared obesity population worldwide, hepatosteatosis is becoming a major risk factor for hepatocellular carcinoma (HCC). Undertaken molecular events during the progression of steatosis to liver cancer are thus under intensive investigation. In this study, we demonstrated that high-fat diet potentiated mouse liver AKT2. Hepatic AKT2 hyperactivation through gain-of-function mutation of Akt2 (Akt2E17K) caused spontaneous hepatosteatosis, injury, inflammation, fibrosis, and eventually HCC in mice. AKT2 activation also exacerbated lipopolysaccharide and D-galactosamine hydrochloride-induced injury/inflammation and N-Nitrosodiethylamine (DEN)-induced HCC. A positive correlation between AKT2 activity and SCD1 expression was observed in human HCC samples. Activated AKT2 enhanced the production of monounsaturated fatty acid which was dependent on SREBP1 upregulation of SCD1. Blockage of active SREBP1 and ablation of SCD1 reduced steatosis, inflammation, and tumor burden in DEN-treated Akt2^E17K mice. Therefore, AKT2 activation is crucial for the development of steatosis-associated HCC which can be treated with blockage of AKT2-SREBP1-SCD1 signaling cascade.