Heat shock factor 2 (HSF2) and hypoxia-inducible factor 1α are activated by angiotensin II (ANGII) in cardiomyocytes. The endoplasmic reticulum (ER) stress plays a critical role in cardiac hypertrophy. Moreover, HIF-1α is known to be regulated by HSF2 in tumour cells. In this study, we hypothesised and clarified whether HSF2 trans-activated HIF-1α through initiation of ER stress in hypertrophic cardiomyocytes. Myocardial hypertrophy was induced by the treatment of ANGII. Expression of the gene or protein was assessed by applying RT-PCR, WB, ICC and IHC. Luciferase and CHIP were applied to detect the transcription of HIF-1α by HSF2. Both in vitro and in vivo, the expression of HIF-1α, ER stress markers and HSF2 was increased in ANGII-treated hypertrophic cardiomyocytes. Blocking ER stress suppressed the expression of HSF2 and HIF-1α in ANGII-treated cardiomyocytes. Silencing HSF2 inhibited HIF-1α, thereby reducing hypertrophy but had no effect on ER stress. Similarly, silencing HIF-1α reduced hypertrophy without affecting ER stress or HSF2 expression. HSF2 transcriptionally activated HIF-1α. We concluded that ER stress induced by ANGII activates HSF2, which then trans-activates HIF-1α, promoting cardiac hypertrophy.
Hypertrophic Cardiomyopathy (HCM) is one of the significant causes of heart failure. This study aimed to identify and validate potential therapeutic targets for HCM through bioinformatics analysis and in vitro and in vivo experiments. By analysing differentially expressed genes in HCM patients and combining multiple analytical approaches, key genes were screened. The functions of these genes were validated using AC16 cells under different mechanical force environments and Ang-II induction. HCM-like pathological cardiac remodelling mouse model was established to evaluate myocardial hypertrophy, fibrosis and cardiac remodelling. The results demonstrated that DUSP1 expression was downregulated in the myocardium of HCM patients. Mechanical force transduction activated the MAPK pathway and overexpression of DUSP1 suppressed ERK/MAPK activation and attenuated mechanotransduction-associated cardiomyocyte hypertrophy and hypertrophic gene expression. In vivo experiments showed that cardiac-specific restoration of DUSP1 expression alleviated pathological cardiac remodelling and fibrosis. This study suggests that DUSP1 functions as an endogenous regulator of mechanically activated MAPK signalling, thereby limiting pathological myocardial hypertrophy. These findings identify a previously underappreciated role of DUSP1 in linking mechanical stress-induced signalling with MAPK activation and pathological cardiac remodelling, suggesting DUSP1 restoration as a potential therapeutic strategy for HCM-like cardiac remodelling.
OBJECTIVE:This study aims to elucidate the molecular mechanisms by which Polyphyllin I (PPI), a potent steroidal saponin, attenuates non-small cell lung cancer (NSCLC) progression via mechanistic reprogramming of an autophagy-dependent immunogenic response. METHODS:Integrated in vitro (A549, H460) and in vivo (LLC xenograft) models were deployed to evaluate PPI's efficacy on autophagic flux and the tumour immune microenvironment. The regulatory role of autophagy in macrophage-mediated antigen presentation was scrutinised via ATG3-mediated genetic silencing or overexpression in tumour-macrophage co-culture systems. Concurrently, the capacity of PPI to sensitise NSCLC cells to cisplatin (DDP) and counteract chemoresistance was evaluated. RESULTS:PPI activated the AMPK/p53/mTOR signalling axis, robustly inducing core autophagic markers (LC3-II and Beclin-1) in a dose-dependent manner. Mechanistically, PPI-induced autophagic flux served as a prerequisite for antitumoural M1 macrophage polarisation, characterised by significant upregulation of iNOS and MHC-II in co-cultured THP-1 cells. Genetic knockdown of ATG3 effectively abrogated these immunostimulatory profiles, whereas ATG3 overexpression potentiated PPI-driven antigen presentation. Furthermore, PPI administration markedly delayed the onset of DDP resistance sustained by functional autophagic flux. In vivo, PPI significantly suppressed tumour burden, accompanied by enhanced CD8+ T-cell infiltration and elevated cytotoxic effector levels (IFN-γ and Granzyme B). CONCLUSION:Our findings establish PPI as a dual autophagic-immune modulator that re-engineers the immunosuppressive microenvironment. By coupling intracellular autophagic stress with macrophage-mediated antigen presentation, PPI reinstates antitumour immunity and abrogates chemoresistance, offering a compelling therapeutic framework for managing recalcitrant NSCLC.
BACKGROUND:Food allergy (FA) is a disorder marked by a significant incidence of detrimental immunological responses to certain dietary constituents, while preventive measures and regulatory treatments are scarce. Mast cells (MCs) are integral to the pathogenesis of FA mediated by Immunoglobulin E (IgE). The activation of MCs is modulated by their intracellular Ca2+ concentrations, with CaV1.2 serving as a voltage-gated calcium channel that regulates calcium influx in MCs. OBJECTIVE:The aim of this study was to examine the influence of CaV1.2 on MCs' activation and its role in the onset and progression of FA. METHODS:The inhibitory effect of nimodipine (Nim) on MCs activation in vitro was evaluated by detecting LAD2 degranulation and cytokine release; the anti-food allergy effect of Nim was examined by the establishment of an IgE-mediated FA model; the effect of CaV1.2 on the occurrence of FA was investigated using conditional knockout of CaV1.2 in MCs (CKO) mice. RESULTS:Nim inhibited MCs activation in vitro and alleviated ovalbumin (OVA)-induced FA in vivo. The expression of CaV1.2 in MCs exhibited detrimental effects, whereas its deficiency ameliorated local and systemic allergy and significantly alleviated FA in mice. When CaV1.2 was replenished in CKO mice by BMMC injection, such supplementation exacerbated FA symptoms. CONCLUSION:Depression of CaV1.2 in MCs attenuates the activation of MCs and alleviates the symptoms of FA. These results suggest that CaV1.2 could be a new target for FA.
Thalassaemia is a hereditary haemoglobinopathy characterised by impaired globin synthesis, resulting in ineffective erythropoiesis and systemic iron overload. While current management relies on blood transfusions and chelation, these often fail to address the underlying molecular signalling dysregulation that contributes to the disease's progression, such as the imbalance in erythropoietin production and the activation of inflammatory pathways. Brazilin, the primary homoisoflavonoid from Biancaea sappan L., presents a multifaceted therapeutic profile. This review synthesises evidence of brazilin's activity as a potent iron chelator and reactive oxygen species (ROS) scavenger and anti-inflammatory agent, while evaluating its potential as a novel JAK2 inhibitor. Molecular docking suggests brazilin may bind to the JAK2 ATP-binding pocket, though functional validation is still required. By modulating the erythroferrone (ERFE)-hepcidin (HAMP) axis, brazilin potentially restores iron homeostasis and mitigates splenomegaly. We further evaluate its pharmacokinetics and safety profile, highlighting low toxicity and high oral bioavailability. This positions brazilin as a promising lead candidate for thalassaemia adjunct treatment, warranting further in vivo validation.
Pentraxin 3 (PTX3) responds rapidly to inflammatory signals. This study investigated the functional involvement of PTX3 in angiotensin II (Ang II)-mediated cardiac hypertrophy pathogenesis, with particular focus on its potential regulation through inflammatory pathways and oxidative stress mechanisms. In vivo, chronic Ang II infusion over 4 weeks was used to induce hypertrophic cardiomyopathy in mice. In parallel, an in vitro model of cardiomyocyte hypertrophy was established by treating neonatal rat cardiomyocytes (NRCMs) with Ang II for 24 h. Ang II treatment significantly increased PTX3 expression, an effect observed in both mouse heart tissue and NRCMs. The cardiac hypertrophy and fibrosis in mice treated with Ang II were alleviated by PTX3 knockout. Genetic ablation of PTX3 attenuated Ang II-induced upregulation of cardiac hypertrophy markers in mice hearts, including atrial natriuretic peptide, brain natriuretic peptide, and beta-myosin heavy chain. Additionally, PTX3 knockout suppressed the elevation of pro-inflammatory cytokines, including tumour necrosis factor-alpha and interleukin-1beta, following Ang II stimulation. Genetic deficiency of PTX3 significantly ameliorated cardiac oxidative stress potentiated by Ang II infusion. These outcomes showed that targeting of PTX3 could ameliorate hypertrophic cardiomyopathy via attenuation of inflammatory response and oxidative stress. PTX3 may be a target for therapy of hypertrophic cardiomyopathy in the future.
BACKGROUND:Hepatocellular Carcinoma (HCC) is a matter of great global public health importance; however, its current therapeutic effectiveness is deemed inadequate, and the range of therapeutic targets is limited. This study aimed to explore the efficacy of Bosutinib (BOS) in HCC and the underlying molecular mechanism. METHODS:Bioinformatic analysis, machine learning, and online databases were used for screening targets and molecular docking studies. The mRNA level of mammalian polo-like kinase 1 (PLK1) was identified via real-time quantitative PCR. The protein expression of PLK1, PTK2, and USP9X was detected using western blot. Cell viability, apoptosis, and migration were evaluated by MTT, flow cytometry, and transwell assay. The angiogenesis capacity was determined using tube formation assay. The glucose consumption, lactate production, and ATP/ADP ratios were analysed using commercial kits. CO-IP assay was used to confirm the interaction between PLK1 and USP9X. A mouse model was used for exploring BOS in vivo. Immunochemistry was used to examine PLK1 and USP9X expression in tumours. RESULTS:This study illustrated that BOS inhibited proliferation, migration, angiogenesis, and glycolysis of HCC cells. Bioinformatic analysis and machine learning identified PLK1 as a core gene related to the glycolysis of HCC. PLK1 was upregulated in HCC and correlated with an unfavourable prognosis. Further evaluation showed that the anti-tumour effects of BOS were impaired by PLK1 overexpression. In addition, BOS treatment inhibited PLK1 protein level, while its mRNA level was not affected. Moreover, Bosutinib inhibited USP9X to reduce the deubiquitination of PLK1. CO-IP assay indicated that reduced USP9X could enhance the ubiquitination of PLK1 and reduce protein stability. Finally, BOS showed anti-tumour effects in a mouse model. CONCLUSION:This study revealed that BOS inhibited cell proliferation, migration, angiogenesis, and glycolysis via suppressing USP9X, thus reducing deubiquitination of PLK1 in HCC, demonstrating the potential of BOS for the treatment of HCC.
BACKGROUND:Intrinsic capacity (IC), proposed by the World Health Organization, reflects the composite of an individual's physical and mental capacities and is considered a key indicator of healthy aging. Although air pollution has been associated with multiple adverse health outcomes, evidence on its relationship with IC-a multidimensional indicator of overall functional ability-remains limited. OBJECTIVE:This study aimed to examine the longitudinal associations between long-term exposure to particulate matter of different sizes (PM1, PM2.5 and PM10) and declines in intrinsic capacity among middle-aged and older adults in mainland China. METHODS:Data were obtained from the nationally representative longitudinal cohort of the China Health and Retirement Longitudinal Study (CHARLS), including adults aged ≥ 45 years. Annual average concentrations of PM1, PM2.5 and PM10 were estimated using satellite-based models based on participants' residential locations. A composite IC score was constructed according to the WHO intrinsic capacity framework. Multivariable logistic regression models were used to evaluate associations between particulate matter exposure and IC decline. Restricted cubic spline models were applied to assess nonlinear dose-response relationships. Mixed-exposure effects were further evaluated using weighted quantile sum regression, Bayesian kernel machine regression and quantile g-computation. RESULTS:Long-term exposure to PM1, PM2.5 and PM10 was significantly associated with a higher risk of IC decline and lower composite IC scores. Nonlinear dose-response relationships were observed between particulate matter exposure and IC decline. In mixed-exposure analyses, PM10 and PM2.5 showed the strongest contributions to the joint effects, with PM10 having the highest weight and posterior inclusion probability. Each one-quantile increase in the overall pollutant mixture was significantly associated with a decline in composite IC scores.
BACKGROUND:Type 2 Diabetes Mellitus (T2DM) and AF (Atrial Fibrillation) frequently coexist, amplifying cardiovascular risks via shared mitochondrial dysfunction involving metabolic dysregulation, oxidative stress, and inflammation. While the SGLT2 inhibitor dapagliflozin (DAPA) demonstrates cardiorenal protection through mitochondrial improvement, its direct mechanistic actions in T2DM-AF patients remain unknown. Our study aimed to elucidate DAPA's mitochondrial regulatory mechanisms in T2DM-AF to break the vicious cycle of mitochondrial dysfunction remodelling, addressing an unmet clinical need in this high-risk population. METHODS:The high-glucose atrial fibrillation (HG-AF) model was established using 30 mM glucose combined with 10 Hz electrical stimulation, followed by validation through glucose uptake assay, electrophysiology, and fibrosis-related protein and calcium transient analysis. Mitochondrial function was evaluated using ROS/JC-1 probes, ATP quantification, and mitochondrial-related protein expression. To investigate the role of DAPA, we assessed its activation of the AMPK/PGC-1α/SIRT3 signalling pathway via western blot and further confirmed the mechanism using the AMPKα inhibitor Compound C. In addition, a mouse model of HG-AF was established to further validate the in vitro results. RESULTS:Cell experiments showed that after treatment with 30 mM glucose and 10 Hz electrical stimulation, HL-1 cells exhibited increased 2-NBDG uptake, decreased Fluo-4 AM intensity, upregulation of glucose transporters and fibrosis-related proteins, and disrupted electrophysiological protein expression, confirming the successful establishment of the HG-AF model. DAPA treatment attenuated fibrosis, restored electrophysiological protein expression, decreased Drp1, and increased OPA1 and SOD2 levels. It also enhanced Fluo-4 AM intensity, reduced ROS, improved JC-1 aggregates, and boosted ATP production. In vivo experiments further confirmed that in HG-AF mice, the duration of AF and the RR interval were significantly prolonged, and there was upregulation of CaMKII/ox-CaMKII, downregulation of ion channel proteins, and elevated levels of fibronectin in cardiac tissue. DAPA treatment activated the AMPK/PGC-1α/SIRT3 pathway, reduced the acetylation levels of OPA1 and SOD2, increased ATP levels, and decreased MDA levels. Pretreatment with Compound C abolished the DAPA-induced activation of the aforementioned pathway and the improvement in mitochondrial function. CONCLUSION:In the HG-AF setting, DAPA attenuated cardiomyocyte damage by enhancing mitochondrial function through activation of the AMPK/PGC-1α/SIRT3 signalling pathway.
BACKGROUND:Atherosclerosis (AS) is a major cause of cardiovascular diseases, with OX-LDL-induced VSMC dysfunction being a critical pathogenic driver of AS development. Saikosaponin D (SSD), a bioactive compound, shows therapeutic potential, but its mechanism in AS is unclear. METHODS:An atherosclerotic cell model was established by treating hVSMCs with OX-LDL. Intracellular ROS was detected via a fluorescent probe, MDA content and SOD activity via biochemical kits. Inflammatory cytokines (IL-6, IL-8 and TNF-α) were quantified by ELISA. Lipid parameters (TG, LDL and HDL) were analysed biochemically, and intracellular lipid accumulation was assessed via Oil Red O staining. Autophagy (LC3B and p62) and senescence-related (p16 and p21) protein expression was detected by WB, with cellular senescence further assessed via SA-β-gal staining. SSD's potential targets were predicted via bioinformatics (CTD, SwissTargetPrediction and GeneCards). SSD-EPHB2 interaction was predicted by AutoDock Vina docking (visualised by PyMOL), and its stability was evaluated by using iMODS-based NMA. EPHB2's functional role was confirmed via its overexpression in hVSMCs. RESULTS:SSD significantly attenuated OX-LDL-induced oxidative stress, inflammation, lipid accumulation, autophagic flux impairment and cellular senescence in hVSMCs. Bioinformatics analysis pinpointed EPHB2 as a hub gene. Molecular studies confirmed that SSD directly binds to EPHB2 and downregulates its expression. Crucially, overexpressing EPHB2 abolished all the protective effects of SSD. CONCLUSION:SSD alleviates OX-LDL-induced hVSMC dysfunction by inhibiting EPHB2, highlighting the SSD-EPHB2 pathway as a potential therapeutic target for AS.
PURPOSE:To explore the feasibility of phase contrast (PC) MRI and three-dimensional pulsed arterial spin labelling (3D PASL)-MRI in assessing cerebrovascular blood flow changes after surgical revascularization in patients with moyamoya disease (MMD). METHODS:This study was a prospective study and comprised two sections. In the first section, 43 patients with MMD who never underwent any revascularization surgery and 19 healthy control volunteers were enrolled. In the second section, 51 patients with MMD who underwent revascularization surgery were included. PC-MRI and 3D PASL-MRI were performed. The average blood flow in the internal carotid (ICA), basilar (BA), superficial temporal (STA) arteries and cerebral blood flow (CBF) were compared between the MMD patients and control volunteers (first section) as well as before and after surgery (second section). Then, MMD patients were divided into haemorrhage and non-haemorrhage subgroups and the average blood flow and CBF before and after surgery were compared between the subgroups. RESULTS:The average flow in the ICA, BA, STA was lower in the MMD patients than in the healthy control group (p = 0.000, p = 0.001, p = 0.001). The CBF of the seven clusters was higher in the healthy controls than in the MMD patients' groups. The average flow in the ICA, BA and STA was increased in MMD patients after combined surgery (p = 0.000, p = 0.002, p = 0.000). Fifteen clusters of elevated CBF and one of reduced CBF were postoperatively evident. Eight clusters of elevated CBF were compared with the preoperative status in the patients without haemorrhage. In the haemorrhage group, postoperative CBF did not significantly change after combined surgery (p > 0.05). CONCLUSION:Both 3D PASL-MRI and PC-MRI can noninvasively evaluate CBF changes in patients with MMD after surgery. The CBF of the cerebral was significantly improved after surgery. Moreover, the improvement of CBF was more obvious in patients with non-hemorrhagic rather than hemorrhagic MMD.
BACKGROUND:Heart failure with preserved ejection fraction (HFpEF) has emerged as one of the most challenging public health issues worldwide, with few effective preventive and therapeutic options available. S100A8/A9 is an inflammatory mediator that contributes to the development of several cardiovascular diseases via the TLR4/NF-κB pathway. This study aimed to investigate the role of S100A8/A9 in HFpEF and unravel potential mechanisms. METHODS:The HFpEF model was established in C57BL6/J mice by administering a high-fat diet combined with NG-nitroarginine methyl ester hydrochloride (L-NAME). From the eighth week, mice were treated with the S100A8/A9 inhibitor paquinimod (ABR 215757) via oral gavage for 8 weeks. Body weight, tibial length, glucose tolerance, and blood lipids were measured following the intervention. Subsequently, cardiac function, myocardial hypertrophy, cardiac fibrosis, inflammatory markers, and oxidative stress were evaluated. AAV9-TLR4-shRNA and the TLR4 inhibitor TAK-242 were employed in vivo and in vitro, respectively, to explore the probable underlying mechanism. RESULTS:The results showed that paquinimod improved diastolic dysfunction in HFpEF mice without affecting systolic function. It also mitigated cardiomyocyte hypertrophy, suppressed cardiac fibrosis, decreased myocardial inflammation, and attenuated oxidative stress. Mechanistically, paquinimod inhibited the TLR4/NF-κB signalling pathway, and TLR4 inhibition reversed the effects of S100A8/A9 in vitro and partly alleviated the heart failure phenotype in mice with HFpEF. CONCLUSIONS:Inhibition of S100A8/A9-mediated inflammation improved diastolic function and reversed the pathological changes of the heart in mice with HFpEF. The observed effects were potentially mediated via inhibition of the TLR4/NF-κB pathway. The present study identified S100A8/A9 as a possible therapeutic target in HFpEF.
OBJECTIVE:Diabetic nephropathy (DN) represents a significant complication of diabetes and serves as a primary trigger for end-stage renal disease. The study aimed to investigate the renal protective influence of Cynomorium songaricum Rupr. polysaccharide (CSP) on inflammation and oxidative stress in DN and explore its related mechanisms. METHODS:High glucose (HG)-stimulated podocytes (MPC-5 cells) were used as the cell model for DN. Cell counting kit-8 assay, flow cytometry analysis, and detection of lactate dehydrogenase production were performed to measure cell viability, apoptosis and cell death. A diabetic mouse model was established through streptozotocin induction. Levels of blood urea nitrogen (BUN), serum creatinine and 24-h urine protein were measured to assess renal function. Immunofluorescence staining of kidney samples was conducted to measure the expression of tumour necrosis factor (TNF)-α and interleukin (IL)-6. Oxidative stress markers of catalase (CAT), superoxide dismutase (SOD) and malondialdehyde (MDA) were measured by corresponding kits. ELISA was performed to assess inflammatory cytokine levels in renal tissue. Western blot was performed to quantify protein levels of factors related to apoptosis, inflammation, oxidative stress and AMPK/SIRT1 pathway. RESULTS:CSP protected MPC-5 cells from HG-induced injury by inhibiting cell apoptosis and death while increasing cell viability. In addition, CSP notably repressed oxidative stress as manifested by an increase in CAT and SOD activities and a decline in MDA content, NOX2 level and NOX4 level. Meanwhile, the significant downregulation of IL-6, TNF-α, IL-1β, COX-2 and iNOS levels was found in HG-treated MPC-5 cells in the context of CSP administration. More importantly, CSP treatment attenuated inflammation and oxidative stress in the renal tissue of DN mice. CSP activated the AMPK/SIRT1 signalling in the renal tissue of DN mice. CONCLUSION:CSP inhibits DN progression by alleviating inflammatory response and oxidative stress via activation of the AMPK/SIRT1 signalling.
Marfan syndrome (Mfs) arises from mutations in FBN1, predisposing individuals to thoracic aortic aneurysm (TAA) through abnormal smooth muscle cell behaviour. The role of HSPB7 in Mfs-related TAA remains poorly understood. By integrating multi-omics analysis with hiPSC-derived VSMCs from patients with Mfs, we elucidated the molecular landscape of Mfs-associated TAA. Analysis revealed immune cell infiltration, a reduced proportion of VSMCs, and altered intercellular communication. Pathway analyses indicated changes in cell adhesion, extracellular matrix (ECM) remodelling, and immune signalling, with downregulated metabolic pathways. Findings suggest structural, immune, and metabolic imbalances in Mfs-TAA pathogenesis. Downregulation of HSPB7 was associated with altered proliferation, migration, and metabolic activity. Overexpression of HSPB7 in patient-specific hiPSC-derived VSMCs attenuated these pathological features and promoted a more contractile phenotype. These findings suggest that HSPB7 may be involved in the regulation of VSMCs' phenotypic modulation in Mfs-TAA and provide mechanistic insight into disease-associated cellular alterations.
Lung cancer continues to be the primary contributor to cancer-related mortality worldwide. While immunotherapy markedly improves outcomes for many patients, clinical evidence indicates that non-small-cell lung cancer (NSCLC) patients with elevated Aurora A expression exhibit reduced therapeutic responses to immune checkpoint blockade. Elucidating the underlying mechanisms may unlock novel strategies to enhance the clinical benefits for this subset. In this study, we characterised cellular senescence and tumour microenvironment interactions using lung cancer cell lines with different Aurora A expression levels. H23 (high Aurora A expression) and A549 (low Aurora A expression) cells were selected to model tumour-immune crosstalk. Tumour-infiltrating lymphocytes (TILs) were isolated and activated via anti-CD28 costimulation. Through gain- and loss-of-function experiments, we established the optimal conditions to induce T-lymphocyte apoptosis and identified critical cell ratios and culture durations. In these co-culture systems, immune checkpoint inhibitors more effectively suppressed Aurora A-low tumour growth. Mechanistically, Aurora A overexpression exacerbated T-lymphocyte apoptosis via the NOXA-MCL-1 pathway. Further analysis revealed that Aurora A disrupts the eIF4G:eIF4E complex by suppressing p4E-BP1, thereby up-regulating the pro-apoptotic factor NOXA while down-regulating the anti-apoptotic factor MCL-1. Aurora A-driven T-lymphocyte apoptosis via the NOXA-MCL-1 axis compromises PD-1/PD-L1-mediated immune responses, providing a molecular rationale for immunotherapy resistance in Aurora A-high NSCLC patients. Targeting this pathway may restore T-cell viability and improve therapeutic outcomes.
Viral infections are a major cause of cardiac metabolic dysfunction, leading to diseases like viral myocarditis and heart failure. In this study, we used G3-YSD, a synthetic DNA mimic from the HIV-1 genome, to model cytoplasmic viral DNA stress and aim to elucidate the mechanistic roles of TRMT13 and SPAST in cardiomyocyte metabolic impairment under conditions mimicking viral infection. Through functional assays such as ATP quantification and Seahorse XF metabolic stress tests on H9C2 and AC16 cells, we found that G3-YSD treatment suppressed cardiomyocyte energy metabolism in a dose- and time-dependent manner, with upregulation of TRMT13 and SPAST. Further analysis revealed a strong positive association between these two genes. Functional knockdown experiments showed that silencing TRMT13 or SPAST alleviated G3-YSD-induced energy metabolic impairment. Mechanistically, miR-409-3p was identified as a key intermediary directly targeting the 3'UTRs of TRMT13 and SPAST, with TRMT13 mRNA acting as a ceRNA to promote SPAST expression. In vivo validation using a G3-YSD-treated mouse model confirmed that knocking down TRMT13 or SPAST, or delivering miR-409-3p mimics, improved cardiac function and systemic metabolic activity, while SPAST overexpression negated these effects. Our study identifies a novel TRMT13-miR-409-3p-SPAST regulatory axis mediating cardiomyocyte energy metabolic decline in response to cytoplasmic viral DNA stress, revealing a nonmethyltransferase, nonimmune, ceRNA-based mechanism of a newly characterised tRNA methyltransferase in viral infection-induced cardiac metabolic dysfunction and proposing new molecular targets for therapeutic intervention.
Hypertension promotes cardiac fibrosis and ultimately leads to heart failure. Piezo1, a new mechanically sensitive cation channel, can transduce mechanical stress into biochemical signals that are necessary for cellular physiological and pathological functions. Although some studies have shown that Piezo1 is involved in the occurrence of cardiovascular disease, whether Piezo1 participates in hypertension-induced cardiac fibrosis, and the detailed molecular mechanisms are still unclear. Experiments were performed on cardiac tissue from spontaneously hypertensive rats (SHRs) and angiotensin II (Ang II)-treated mice. Rat cardiac fibroblasts (RCFs) were exposed to high hydrostatic pressure (HHP, 120 or 180 mmHg) using a self-developed device. We found that Piezo1 expression and β-catenin activation were markedly elevated in the cardiac tissue of hypertensive animals and in HHP-treated RCFs, accompanied by elevated expression of fibrosis factors, including TGF-β1, collagen I and collagen III. Furthermore, the inhibition or knockdown of Piezo1 (GsMTx4 and siRNA) and β-catenin (XAV939) alleviated TGF-β1, α-SMA and collagen expression in HHP-induced RCFs. Importantly, inhibition of Piezo1 decreased the concentration of intracellular Ca2+ and the nuclear translocation of β-catenin. Knockdown of Piezo1 in Ang II-treated mice ameliorated hypertension-induced myocardial fibrosis. Overall, Piezo1 channel activation caused by HHP could result in an increased concentration of intracellular Ca2+ and subsequently mediate the nuclear translocation of β-catenin, leading to the synthesis and secretion of collagen by RCFs. This indicates that targeting Piezo1 could be a potential novel approach for treating cardiac fibrosis induced by hypertension.
Diabetes mellitus (DM) is a chronic metabolic disorder associated with hyperglycemia, dyslipidemia, oxidative stress, inflammation, apoptosis, and renal dysfunction. Although phlorizin (PHL) possesses well-documented antidiabetic properties, its clinical applicability is limited by poor bioavailability and rapid metabolism, which may restrict its therapeutic efficacy. This study evaluated the therapeutic potential of phlorizin (PHL) and its chitosan nanoparticle formulation (PHL-CSNPs) in streptozotocin (STZ)-induced type 1 diabetic rats. Ninety adult male albino rats were randomly divided into six groups (n = 15 each): non-diabetic control, non-diabetic treated with crude PHL, non-diabetic treated with PHL-CSNPs, diabetic untreated (STZ-induced T1DM), diabetic treated with crude PHL, and diabetic treated with PHL-CSNPs. STZ-induced T1DM caused significant reductions in serum insulin, body weight gain, renal antioxidant defences, and mitochondrial function, accompanied by marked elevations in fasting blood glucose, dyslipidemia, oxidative stress markers, pro-inflammatory cytokines, apoptotic markers, and renal fibrotic mediators, as well as pronounced histopathological and ultrastructural kidney damage. In diabetic rats, treatment with PHL-CSNPs significantly improved insulin levels, glucose homeostasis, and body weight, restored lipid profiles and antioxidant enzyme activities, enhanced mitochondrial respiratory complex activities and ATP production, suppressed NF-κB-mediated inflammation, upregulated Nrf2/HO-1 signalling, decreased Bax and caspase-3 levels, increased Bcl-2 levels, and reduced TGF-β1-mediated fibrosis. Crude PHL provided moderate protective effects but was consistently less effective than the nanoparticle formulation. Importantly, the chitosan nanoparticle formulation markedly enhanced the therapeutic efficacy of PHL, likely by improving its stability, bioavailability, and renal tissue delivery, thereby producing stronger antioxidant, anti-inflammatory, and anti-apoptotic effects than crude PHL. Non-diabetic rats treated with either PHL or PHL-CSNPs maintained normal metabolic and renal parameters, confirming the safety of the treatments. Histopathological and ultrastructural analyses further confirmed the preservation of renal architecture in PHL-CSNP-treated diabetic rats. Collectively, this study demonstrates that nanoencapsulation significantly potentiates the biological activity of PHL, providing a clear therapeutic advantage over the crude compound. Overall, these findings demonstrate that PHL-CSNPs provide superior nephroprotective, antioxidant, anti-inflammatory, and metabolic benefits, highlighting their potential as a promising therapeutic strategy for managing type 1 diabetes-induced metabolic and renal complications.
BACKGROUND:Klebsiella pneumoniae (KP)-induced pneumonia has a high incidence rate, and current treatment options remain limited. The efficacy and mechanism of the novel natural compound Ciliatoside A (CA) against KP-induced pneumonia remain unclear. AIMS:Investigating whether CA improves KP-induced pneumonia through the sirtuin 1 (SIRT1)/PTEN-induced putative kinase 1 (PINK1)/Parkin axis. METHODS:KP was used to infect A549 cells, and resistance genes expression was detected using qRT-PCR. To evaluate CA's effect on cell viability, the Cell Counting Kit-8 assay was utilised. Different kits were employed to measure mitochondrial membrane potential, mitochondrial reactive oxygen species (mtROS), and ATP production. Transmission electron microscopy was used to observe autophagosome formation, and cellular autophagy was assessed via Western blot and LC3 fluorescence analysis. Flow cytometry, PI/Hoechst staining, and ELISA were employed to investigate the impacts of CA on A549 cell death and cytokine secretion. A KP mouse pneumonia model was established. Pathological staining was used to observe lung tissue damage and inflammatory infiltration, and Western blot was employed to validate protein expression in vivo. To verify whether CA alleviates KP-induced pneumonia through the SIRT1/PINK1/Parkin axis, intervention with SIRT1 agonists/inhibitors was conducted. RESULTS:CA treatment downregulated drug resistance genes in KP and A549 cells, enhanced the viability of A549 cells following KP infection, and inhibited apoptosis. CA reduced mtROS accumulation, increased mitochondrial membrane potential and ATP production, promoted mitochondrial autophagy, and inhibited NLRP3-mediated inflammasome-mediated cell death. Additionally, CA alleviated pulmonary edema and pathological damage in mice following KP infection, while inhibiting apoptosis and pulmonary inflammation. Following KP infection, the SIRT1/PINK1/Parkin axis was blocked in A549 cells and mouse lung tissue; CA treatment activated this pathway. SIRT1 agonists enhanced the protective impact of CA against KP infection in A549 cells and mouse lung tissue, while SIRT1 inhibitors reduced the protective effect of CA. CONCLUSION:CA improves KP-induced pneumonia through activating the SIRT1/PINK1/Parkin axis to regulate mitochondrial autophagy.
OBJECTIVE:Acute myocardial infarction (AMI) remains the leading global cause of mortality. This study explored the mechanism by which ginsenoside Rg1 (Rg1) ameliorates cardiac function and ventricular remodelling (VR) in rats with AMI by regulating SH2 domain-containing adapter protein B1 (SH2B1). METHODS:An AMI rat model was established by ligating the left anterior descending coronary artery. Gain- and loss-of-function experiments were conducted to explore the role of SH2B1 in mediating cardioprotective effects of Rg1. Cardiac function and VR were evaluated using echocardiography, enzyme-linked immunosorbent assay (ELISA) and histological staining. RT-qPCR and western blot were employed to analyse SH2B1 expression and molecular docking to predict the binding affinity between Rg1 and SH2B1. RESULTS:Rg1 improved echocardiographic parameters, decreased levels of pro-inflammatory cytokines, reduced infarct size, weakened myocardial tissue cell apoptosis, diminished blue collagen fibre deposition and reduced the proportion of α-smooth muscle actin-positive cells in myocardial tissues of rats with AMI in a dose-dependent manner within a certain range. Additionally, SH2B1 mRNA and protein expression was elevated in the myocardial tissue of AMI rats and Rg1 dose-dependently reduced SH2B1 expression. A binding energy of -2.14 kcal/mol was observed between Rg1 and SH2B1, indicating a potential interaction. SH2B1 knockdown improved cardiac function and VR in rats with AMI, and SH2B1 overexpression partially counteracted the beneficial effects of Rg1 in AMI rats. CONCLUSION:Rg1 improves cardiac function and VR in rats with AMI by down-regulating SH2B1; these effects are partially nullified by SH2B1 overexpression.
