Exenatide, the first glucagon-like peptide-1 receptor agonist (GLP-1RA), exerted multiple beneficial effects, including stimulating insulin secretion, slowing gastric emptying, and improving insulin resistance (IR). Our previous work demonstrated that the peroxisome proliferator-activated receptor delta (PPARδ) gene (PPARD) polymorphisms correlated with exenatide monotherapy efficacy, possibly due to the pivotal role of PPARδ in regulating IR. Specifically, PPARδ has been shown to modulate the nucleotide-binding domain and leucine-rich repeat pyrin domain-containing 3 (NLRP3) inflammasome, a key regulator of pyroptosis, thereby participating in the regulation of this inflammatory cell death pathway. However, the underlying mechanisms by which exenatide ameliorated hepatic IR in patients with type 2 Diabetes Mellitus (T2DM) remained incompletely understood. Herein, we found that exenatide suppressed pyroptosis and ameliorated hepatic IR; furthermore, it could bind to PPARδ and upregulate PPARδ protein expression both in vitro and in vivo. Notably, PPARδ knockdown abolished the protective effects of exenatide against pyroptosis and hepatic IR, whereas pharmacological activation of PPARδ enhanced these beneficial effects. Moreover, T2DM patients carrying the AA genotype at PPARD rs3777744 and exhibiting higher baseline homeostasis model assessment of insulin resistance (HOMA-IR) showed a superior response to exenatide. Collectively, our findings revealed that exenatide ameliorated hepatic IR by suppressing pyroptosis via PPARδ, underscoring the potential of PPARD rs3777744 as a biomarker for personalized exenatide therapy in T2DM.

BACKGROUND:Diabetic Nephropathy (DN) is a Chronic Kidney Disease (CKD), and its main pathological changes are renal tubular injury and glomerulosclerosis. Semen Ziziphi Spinosae (SZS) is the seed of Ziziphus jujuba var. spinosa (Bunge) Hu ex H.F. Chow. As a triterpene saponin, Jujuboside A (Ju A) is the main active substance isolated from SZS. This study sought to investigate the potential effect and mechanism of Jujuboside A against DN. METHODS:The anti-apoptotic effects of Ju A on renal parenchymal cells of DN were examined by in vivo and in vitro studies. Molecular docking and Molecular Dynamics (MD) simulation revealed that Ju A could bind to TNF-α and Caspase-3 via forming stable receptor-ligand complexes, respectively. Immunofluorescence (IF) staining and ELISA detection were carried out to investigate the potential mechanisms by which Ju A exerted its amelioration effect on DN. RESULTS:Our study showed that, accompanied by the restored renal function, Ju A inhibited apoptosis of renal tubules and glomeruli in vivo and in vitro. Network pharmacology revealed that 42 overlapping targets were related to Ju A and DN. Among them, IL6, IL1B, TNF, VEGFA, EGFR, ALB, IGF1, FGF2, CASP3, and ESR1 were the top 10 targets. Ju A could bind to TNF-α and Caspase-3 via forming stable receptor-ligand complexes, respectively, as demonstrated by molecular docking and MD simulation. Ju A decreased the protein levels of TNF-α and IL-1β in renal tubules and glomeruli of diabetic mice, and in HG-cultured HK-2 cells and podocytes, leading to the alleviation of inflammation. Besides, the up-regulated relative phosphorylation levels of NF-κB p65 and cleaved caspase-3 were also down-regulated by Ju A in vivo and in vitro. DISCUSSION:The research showed that Ju A had a high affinity for Caspase-3 and TNF-α, and the underlying mechanism of Ju A against DN was the inhibition of apoptosis in renal tubular epithelial cells and podocytes. These findings strengthened the evidence that Ju A could be a potential treatment strategy for DN and offered opportunities for therapeutic advances in the field. CONCLUSION:Ju A could inhibit apoptosis and alleviate inflammation of renal parenchymal cells by inactivating the TNF-α/NF-κB p65/Caspase-3 signaling pathway, exerting renal protective effect against DN.

Our research team developed AB-38b, a biphenyl diester derivative containing α,β-unsaturated carbonyl groups, inspired by investigations into the pharmacological prevention and pathophysiology of diabetic kidney disease (DKD). We have completed the synthesis and pharmacodynamic evaluation of AB-38b in preclinical DKD studies. For pharmacokinetic analysis, we established a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for quantifying AB-38b in rat plasma, as well as in liver and kidney tissues. Sample preparation involved protein precipitation using methanol, with tolvaptan employed as the internal standard (IS). Chromatographic separation was achieved on a Shim-pack VP-ODS C18 column (2.0 × 150 mm, 5 µm), with mobile phase A (5 mM ammonium acetate) and mobile phase B (methanol) under gradient elution at a flow rate of 0.2 mL min-1. AB-38b and the IS were detected and quantified using positive electrospray ionization in multiple reaction monitoring (MRM) mode at transitions of m/z 705.30 → 618.20 for AB-38b and m/z 449.30 → 252.20 for the IS. The method demonstrated excellent linearity, stability, accuracy, precision, recovery, and a non-significant matrix effect within the validated range. A one-compartment model with rapid absorption and distribution, quicker elimination, and clear tissue distribution was demonstrated by the mean blood concentration-time curve of AB-38b in rat plasma. The liver tissue contained high levels of AB-38b, with no evidence of tissue accumulation observed. These findings offer a reference for further research into the pharmacological mechanisms and potential therapeutic applications of AB-38b in metabolically related diseases, especially DKD.

Ferroptosis is a recently characterized, iron-dependent modality of regulated cell death that precipitates organ injury by derailing cellular redox homeostasis and can serve as an indicator of hepatic injury severity. Yet studies linking ferroptosis to liver pathology face two major constraints: (1) fluorescent probes that use iron ions as the analyte suffer interference from specific reaction chemistries, resulting in low sensitivity and poor physiological stability; and (2) the therapeutic promise of modulating ferroptosis in liver injury remains underexplored. To overcome these barriers, this study introduces two non–iron-based biomarkers—lipid droplet polarity and hypochlorous acid-as alternative analytical targets, thereby avoiding the limitations imposed by iron-specific reactions. Accordingly, we engineered NIR-MZY, a dual-responsive probe capable of simultaneously monitoring lipid droplet polarity and hypochlorous acid, thereby assessing the potential of ferroptosis-targeted strategies for the treatment of liver injury. As expected, we tracked dynamic changes in lipid droplet polarity and hypochlorous acid (HOCl) during drug-induced liver injury and visualized their modulation in cellular and zebrafish models under ferroptosis induction and inhibition. These results indicate that manipulating ferroptosis attenuates hepatic damage and substantiate its viability as a therapeutic target. Thus, NIR-MZY emerges as a convenient, sensitive imaging modality that enables precise diagnosis and intervention in ferroptosis-driven liver injury.

Dapagliflozin shows variable renoprotective efficacy in patients with type 2 diabetic kidney disease (T2DKD). A retrospective clinical analysis confirmed marked interindividual variability in its urinary protein-lowering effects. To investigate the mechanism, drug affinity responsive target stability (DARTS) combined with quantitative proteomics was applied for target identification. Subsequent in vivo and in vitro validation suggested that GSK3β acts as a mediator of dapagliflozin-associated nephroprotection. Dapagliflozin directly bound and partially inhibited GSK3β, and GSK3β activity influenced podocyte protection. To translate findings into clinical relevance, a prospective trial was conducted. The GSK3B rs60393216 polymorphism was associated with urinary albumin-to-creatinine ratio (UACR) reduction after dapagliflozin therapy. These findings suggest that GSK3β contributes to the renoprotective effects of dapagliflozin and that GSK3B polymorphisms may influence therapeutic responses in T2DKD.

Sphingosine-1-phosphate receptor 1 (S1PR1), a member of the G protein-coupled receptor (GPCR) family, is a crucial therapeutic target for various diseases. Activation of S1PR1 has been recognized as an effective therapeutic strategy for multiple sclerosis (MS), inflammatory bowel disease (IBD), and psoriasis. Natural products (NPs) serve as a rich source of bioactive compounds for drug discovery. Here, we aimed to discover novel S1PR1 agonists from NPs via multi-level virtual screening (VS). Using a validated HipHop pharmacophore model, we screened a database containing 54,642 NPs, followed by molecular docking. Based on binding mode analysis, four candidate S1PR1 agonists (NPC323626, NPC264112, NPC469907, and NPC22192) were selected. Subsequent molecular dynamics (MD) simulations and binding free energy calculations confirmed the stability of the receptor-ligand complexes and their binding affinities. Among the four candidates, NPC469907 exhibited the strongest binding affinity for S1PR1, with a value of -58.08 ± 0.13 kJ/mol. Furthermore, hydrogen bonds formed between NPC469907 and Glu121 of S1PR1 were found to be essential for receptor activation. Quantum mechanical calculations further revealed that the phenyl-ring-attached hydrogen site in NPC469907 could be modified without compromising its ability to activate S1PR1. The analysis of Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET) indicated that NPC469907 possessed favorable pharmacokinetic properties and low toxicity. In conclusion, our study identified NPC469907 as a promising natural S1PR1 agonist and established an effective VS strategy for the discovery of novel S1PR1 agonists.

Pathological hypoxia such as high-altitude exposure is harmful to the human body system and multiply organs. However, the systemic damage effects of hypoxia on the intestine and liver tissue remain unclear due to the limitations of traditional 2D cell cultures and animal models. Here, we establish a biomimetic gut-liver microphysiological system (GLMPS) as a human model of the gut-liver axis by coculturing human gut and liver cell lines interconnected under circulating fluid flow, for investigating the mechanisms of hypoxia-induced injury in the intestine and liver. By treatment with 1% O2 for 48 h, cocultured Caco-2/HT29 gut cells and HepG2 hepatocyte-like cells exhibit increased intestinal barrier permeability, inflammatory responses, and cellular apoptosis. Transcriptomic analysis reveals similar activated pathways associated with endoplasmic reticulum stress and apoptosis in the gut and liver cells. Furthermore, quercetin effectively attenuates hypoxia-induced oxidative stress and apoptosis by enhancing autophagy. The GLMPS provides a biomimetic in vitro platform for studying hypoxia-related pathologies of gut and liver and facilitating the exploration of therapeutic targets.

Preclinical studies have suggested that Ras-related C3 botulinum toxin substrate 1 (RAC1) accelerates diabetic kidney disease (DKD) progression by triggering renal inflammation/fibrosis. Nevertheless, the clinical relevance of RAC1 with DKD is undefined. In this study, we aimed to investigate the association between circulating RAC1 levels and early DKD to evaluate its potential as a novel biomarker for early disease detection. A total of 150 participants were recruited. They were divided into three groups: the type-2 diabetes mellitus (T2DM) group, the early DKD group, and the healthy volunteers (HVs). We measured the circulating level of RAC1 with ELISAs. In addition, we measured levels of two indicators of inflammation (NOD-like receptor pyrin domain-containing 3 (NLRP3) inflammasome, and interleukin (IL)-1β) and two serological indicators reflecting renal fibrosis (fibrillin 1 (FBN1) and matrix metalloproteinase-10 (MMP-10)). The serum level of RAC1 was increased in individuals with early DKD. The serum level of RAC1 was positively correlated with urinary clinical biomarkers, including the urine albumin-to-creatinine ratio (UACR), urine microalbumin (UMA), and α1-microglobulin (α1-MG), but inversely associated with the estimated glomerular filtration rate (eGFR). Serum levels of RAC1, NLRP3, IL-1β, and MMP-10 were strongly inter-correlated in DKD patients. In addition, after correction for pertinent clinical features and the other four biomarkers, an increased risk of early DKD was linked to a higher serum RAC1 level. Analyses of receiver operating characteristic (ROC) curves revealed the area under the ROC curve of serum levels of RAC1, NLRP3, IL-1β, and MMP-10 for identifying early DKD to be 0.785, 0.728, 0.697, and 0.714, respectively. The circulating RAC1 level was associated with early DKD and might be a biomarker for the early stages of DKD.

Glomerular podocytes injury represents a critical pathological hallmark of diabetic kidney disease (DKD), in which lipotoxicity plays a central pathogenic role. Our previous investigations in type 2 diabetes mellitus (T2DM) have demonstrated that Jujuboside A (Ju A), a triterpene saponin isolated from Semen Ziziphi Spinosae (SZS), exerted dual therapeutic effects in T2DM by ameliorating hepatic steatosis and renal dysfunction. However, the role of podocytes lipid metabolism in Ju A-mediated protection against DKD remain undefined prior to the present study. In this work, we reported that Ju A significantly attenuated glomerular podocytes injury and lipotoxicity in DKD, while concurrently improving renal function and preserving glomerular morphology. Mechanistically, Yin Yang 1 (YY1)-mediated alleviation of lipotoxicity contributed to the protective effect of Ju A against glomerular podocytes injury, primarily by promoting intracellular cholesterol transport and efflux. In conclusion, our findings demonstrated that Ju A mitigated lipid overload in glomerular podocytes by modulating cholesterol homeostasis via YY1, which not only intercepted the pathological progression of DKD but also provided a potential therapeutic target (YY1) and candidate agent (Ju A) for DKD intervention.

Abnormal lipid droplet accumulation and metabolism can precipitate various diseases. Understanding the dynamics of intracellular lipid droplets, particularly hypochlorite acid (HOCl) and polarity, is crucial for elucidating the onset and progression of these diseases. In this study, we synthesized a near-infrared fluorescent probe, NSSP, featuring a D-π-A structure, which facilitates the independent dual-response detection of HOCl and polarity. NSSP not only reveals the polarity and HOCl fluctuations in inflammatory cells and inflammation in live mice but also differentiates between normal and fatty liver tissues through two distinct channels. Furthermore, the probe has proven effective in identifying neoplasms within live murine models at both the cellular and systemic levels, thereby affirming its utility as an instrumental resource for the precocious detection of carcinomas. This offers a hopeful avenue for the diagnostic scrutiny of pathologies.

Background:Gestational diabetes mellitus (GDM) is a prevalent condition during pregnancy, and macrosomia is a recognized risk associated with it. However, the specific relationship between fasting blood glucose (FBG) levels and the risk of macrosomia in GDM, particularly any potential thresholds for this relationship, remains unclear. Methods:This retrospective cohort study analyzed data from 7,957 pregnant women who underwent antenatal care and delivered at The First People's Hospital of Shangqiu between February 1, 2018, and December 30, 2022. Participants were stratified into three groups based on FBG levels: <5.1 mmol/L, 5.1-7 mmol/L, and ≥7 mmol/L. Multivariable logistic regression analyses were performed to assess the association between FBG levels and the risk of macrosomia. Two-piecewise regression models were applied to identify a threshold for the FBG-macrosomia relationship. Results:The prevalence of macrosomia increased substantially with increasing FBG levels (P < 0.001). The adjusted multivariable logistic regression analyses revealed that compared to women with FBG levels <5.1 mmol/L, those with FBG levels of 5.1-7 mmol/L and ≥7 mmol/L had 4.69 (95% CI: 4.06-5.42) and 8.65 (95% CI: 7.31-10.23) times higher risk of macrosomia, respectively (both P < 0.001). Two-piecewise regression models identified a threshold of 8.037 mmol/L. Below this threshold, each unit increase in FBG was associated with a 1.93-fold increase in the odds of macrosomia (95% CI: 1.83-2.04, P < 0.001). Above this threshold, the association was no longer statistically significant (OR = 1.04, 95% CI: 0.90-1.21, P = 0.587). Furthermore, the stratified analysis also showed a positive association between FBG level and macrosomia. Conclusion:There is a nonlinear relationship between FBG levels during pregnancy and the risk of macrosomia in GDM women, with a potential threshold effect at 8.037 mmol/L. Below the threshold, macrosomia prevalence markedly rises with elevated FBG levels, whereas above it, the association loses significance, implying a potential saturation at very high glucose levels.

Pyroptosis, a lytic inflammatory cell death process, plays a critical role in diabetic nephropathy (DN) progression. Our study identifies Hematopoietic Prostaglandin D Synthase (HPGDS) as a key regulatory factor in this process. Analysis demonstrated that HPGDS expression is positively correlated with pyroptosis-related inflammatory injury in DN patients and db/db mice. In diabetic mice and high glucose-stimulated HK-2 cells, HPGDS drives DN advancement through GSDMD-mediated pyroptosis, leading to renal interstitial inflammation. HPGDS overexpression increased pyroptosis in HK-2 cells and aggravated renal interstitial inflammation. Whereas, HPGDS knockdown experiments yielded opposite results. Mechanistically, we confirmed that HPGDS triggers NLRP3/Caspase1 activation, promoting pyroptosis mediated renal tubular injury and interstitial inflammation. These findings elucidate HPGDS-mediated pyroptosis as a therapeutic strategy for DN.

The role of genetic susceptibility in early warning and precise treatment of diabetic kidney disease (DKD) requires further investigation. A case-control study was conducted to evaluate the predictive effect of GSK3B genetic polymorphisms on the susceptibility to DKD, with the aim of providing a theoretical basis and laboratory rationale for the prediction of the risk of developing DKD in patients with type 2 diabetes mellitus (T2DM). The GSK3B genotyping was performed by SNaPshot method based on Genotype-Tissue Expression database and thousand genomes database to screen tag SNPs. The polymorphisms of GSK3B tag SNPs were statistically analyzed for their effects on DKD susceptibility and clinical indicators. Urinary exosomes from DKD patients were extracted, protein expression levels of GSK3β were detected by ELISA kits, and kinase activity of GSK3β was quantified by kinase activity spectrometry to evaluate the correlation between the gene polymorphisms of GSK3B and the expression levels and activities of GSK3β. A machine learning model was constructed for assessing the efficacy of GSK3B polymorphisms in predicting the risk of developing DKD in patients with T2DM. A total of 800 subjects who met the inclusion and exclusion criteria were included in the case-control study, including 200 healthy control subjects, 300 patients with T2DM and 300 patients with DKD. Genetic analysis identified five tag SNPs (rs60393216, rs3732361, rs2199503, rs1488766, and rs59669360) associated with the susceptibility to DKD. The protein level and activity of GSK3β were significantly elevated in DKD patients. On the other hand, the expression levels and kinase activity of GSK3β in exosomes differed significantly between patients with different genotypes of the GSK3B, suggesting that the effect of GSK3B gene polymorphisms on GSK3β expression and activity may be an important mechanism leading to individual differences in susceptibility to DKD. XG Boost algorithm model identified rs60393216 and rs1488766 as important biomarkers for clinical early warning of DKD.

Mesangial cells (MCs) are the most active intrinsic cells in the glomerulus. MCs excessively proliferate at the early stage of diabetic kidney disease (DKD), eventually causing glomerular sclerosis and even renal failure; inhibiting glomerular MC proliferation in early DKD is a promising prevention and treatment strategy for early DKD. Our previous study shows that Yin Yang 1 (YY1), a zinc finger protein, is a novel regulator of DKD-induced renal fibrosis. In this study we investigated the role of YY1 in glomerular MC proliferation in DKD in vivo and in vitro. We first showed that YY1 expression levels were significantly increased in the glomerular MCs of DKD patients and db/db mice and in high glucose (HG)-treated SV40-MES13 cells. By using YY1 expression/knockdown plasmids, we confirmed that YY1 contributed to glomerular MC proliferation in vitro. We demonstrated that YY1 upregulated hypoxia-inducible factor-1 alpha (HIF-1α) expression and activity in HG-treated SV40-MES13 cells, leading to overproduction of mROS. Moreover, mROS contributed to positive feedback regulation of YY1/HIF-1α signaling, and the YY1/HIF-1α/mROS positive feedback loop exacerbated glomerular MC proliferation in HG-treated SV40-MES13 cells. In addition, renal-specific YY1 overexpression promoted glomerular MC proliferation in normal mice, whereas renal-specific YY1 knockdown mitigated MC proliferation in early diabetic mice by inactivating HIF-1α/ROS signaling. In conclusion, the YY1/HIF-1α/mROS positive feedback loop might be an attractive therapeutic target for overcoming glomerulosclerosis in early DKD.

Probiotic supplementation was a novel therapeutic approach for treating metabolic related diseases via “gut-liver” axis. However, the effect of Clostridium butyricum (CB) supplementation on type 2 diabetes mellitus (T2DM)-associated steatohepatitis was unknown. This study revealed that CB alleviated liver damage and hepatitis in 18 weeks-old db/db mice. Targeted metabolomics analysis showed that the dysregulated short chain fatty acids (SCFAs) metabolism homeostasis was regained by CB in the colon content of db/db mice, especially butyric acid. Treatment with sodium butyrate (NaB) significantly attenuated steatosis, inflammation, and fibrosis of db/db mice, and high glucose (HG) and free fatty acid (FFA) co-treated HepG2 cells. In-depth mechanism research suggested that the hepatoprotective effects of CB on T2DM was associated with the suppression of IκB-α/β-arrestin2/NF-κB signaling pathway via intestinal butyrate-medicated hepatic Takeda G-protein-coupled receptor 5 (TGR5). Overall, our results demonstrated a potential novel mechanism for CB as effective nutritional intervention for T2DM-related steatohepatitis via “gut-liver” axis.

Metabolic dysfunction-associated fatty liver disease (MAFLD) has emerged as a leading cause of chronic liver disease worldwide, with its pathological mechanisms involving multiple factors such as hepatic steatosis, insulin resistance (IR), oxidative stress, and inflammatory responses. In recent years, Sirtuin 1 (SIRT1) has been recognized as a crucial molecular target for improving MAFLD due to its central role in metabolic regulation and cellular homeostasis. This article reviews the mechanisms by which SIRT1 intervenes in the progression of MAFLD: 1) promoting autophagy and enhancing mitochondrial function; 2) regulating lipid metabolism and oxidative stress-related proteins through deacetylation, thereby improving lipid metabolism disorders and reducing ROS accumulation; 3) suppressing inflammatory responses and alleviating liver inflammation damage; 4) ameliorating IR. Preclinical studies have shown that SIRT1 agonists or gene overexpression can significantly improve the histopathological features of MAFLD in animal models. However, the regulation of SIRT1 is tissue-specific and dose-dependent, and its long-term safety and targeted delivery strategies require further exploration. This article systematically summarizes the molecular mechanisms and therapeutic potential of SIRT1 in MAFLD, providing a theoretical basis for developing novel intervention strategies based on SIRT1 regulation.

Effectively alleviating cerebral ischemia-reperfusion (I/R) injury is challenging despite the medical advances. Prompt restoration of blood flow after ischemic stroke causes secondary damage to the brain tissues, triggers neuroinflammation and overproduces reactive oxygen species (ROS). MiRNA regulates the genes involved in neuron apoptosis and neuroinflammation, thus exhibiting potential in ameliorating cerebral I/R injury. However, as miRNA is vulnerable to degradation, its effective delivery faces obstacles in clinical applications. Inspired by the therapeutic potential of miR-210 inhibitors in ischemic stroke-induced neuroinflammation, we constructed a multifunctional nanosystem composed of ceria nanozymes and zeolitic imidazolate framework-90 (ZIF-90) nanoparticles to deliver miR-210 inhibitors to treat cerebral I/R injury. Attributed to the proton sponge effect of ZIF-90, this nanosystem allows for the lysosome escape of miR-210 inhibitors to protect their intracellular bioactivity, while the integration of ZIF-90 and ceria nanozymes utilizes multi-enzyme cascade activities to constrain lipid peroxidation and reduce oxidative damage in brain tissues of mice with middle cerebral artery occlusion (MCAO). After crossing the blood-brain barrier, miR-210 inhibitors target TET2 to suppress pro-inflammatory cytokines, finally inhibiting neuroinflammation. More than the uncertain stability and efficacy of direct TET2 protein administration, the delivery of miR-210 inhibitors by multifunctional nanosystems engendered neuroprotection, indicating their potential for protein replacement therapy against cerebral I/R injury.

Abnormal proliferation of mesangial cells is a hallmark of diabetic nephropathy (DN). However, the cellular signaling mechanisms that regulate this proliferation remain poorly understood. In this study, it is demonstrated that GA-binding protein (GABP), a member of the ETS family of transcription factors composed of GABPα and GABPβ, plays a significant role in the development of renal fibrosis by modulating mesangial cell proliferation. Notably, the deficiency of GABP in mesangial cells inhibits hyperglycemia-induced proliferation and mitigates renal fibrosis in a murine model of type 2 diabetes mellitus (T2DM). RNA sequencing analysis identifies GLI Family Zinc Finger 1 (GLI1) as the principal downstream effector of GABP in diabetic mice, serving as a crucial regulator of the G1/S transition within the cell cycle. Subsequent investigations have demonstrated that GABP interacts with the GLI1 promoter, facilitating mesangial cell proliferation via GLI1-dependent pathways. This is evidenced by the fact that GLI1 knockdown abrogates the proliferation of mesangial cells with GABP overexpression. Consequently, GABP emerges as a pivotal regulator of renal fibrosis and represents a promising therapeutic target for the treatment of diabetic nephropathy.

Background Renal tubular injury was a significant pathological change of diabetic kidney disease (DKD), and the amelioration of renal tubular injury through mitochondrial function was an important treatment strategy of DKD. Our previous study had revealed that Jujuboside A (Ju A), the main active substance isolated from Semen Ziziphi Spinosae (SZS), could restore renal function of diabetic mice. However, its protective mechanism against DKD remains unclear. Purpose To investigate the effects and the mechanism of Ju A against DKD-associated renal tubular injury. Study design and Methods The anti-apoptotic effect of Ju A and its protection effect on mitochondria dysfunction of renal tubular epithelial cells (RTECs) were examined in high glucose (HG)-cultured HK-2 cells, and in db/db mice. Subsequently, Network Pharmacology analysis, molecular docking, luciferase assay, chromatin immunoprecipitation (ChIP), Yin Yang 1 (YY1) overexpression lentiviral vector and peroxisome proliferator-activated receptor-γ coactlvator-1α (PGC-1α) specific agonist ZLN005 were all used to identify the protective mechanism of Ju A towards DKD-associated mitochondrial dysfunction of RTECs. Results Ju A inhibited RTECs apoptosis and ameliorated mitochondria dysfunction of RTECs of diabetic mice, and HG-cultured HK-2 cells. YY1 was the potential target of Ju A against DKD-related mitochondrial dysfunction, and the down-regulation of YY1 induced by Ju A increased PGC-1α promoter activity, leading to the restored mitochondrial function of HG-treated HK-2 cells. Renal tubule specific overexpression of YY1 intercepted the renal protective effect of Ju A on diabetic mice via blocking PGC-1α-mediated restoration of mitochondrial function of RTECs. The in-depth mechanism research revealed that the protective effect of Ju A towards DKD-associated renal tubular injury was linked to the restored mitochondrial function through YY1/PGC-1α signaling, resulting in the inhibited apoptosis of RTECs in diabetic condition via inactivating CytC-mediated Caspase9/Caspase3 signaling. Conclusion Ju A through the inhibition of mitochondria-dependent apoptosis alleviated DKD-associated renal tubular injury via YY1/PGC-1α signaling.