Schisanhenol (Sal) is a lignan component derived from the traditional Chinese medicine Schisandra rubrifora (Franch.). Pharmacological research has highlighted that Sal exhibits pronounced neuroprotection against oxidative stress-triggered damage. An in vivo mice model of Parkinson’s disease (PD) was developed using 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), and in vitro studies employed 1-methyl-4-phenylpyridinium (MPP+) as a neurotoxin in SH-SY5Y cells. Behavioral tests, immunohistochemistry, biochemical analyses, cell viability assays, and Western blot were applied. Sal (50 mg/kg and 100 mg/kg) markedly alleviates behavioral disorders in mice. The quantity of tyrosine hydroxylase (TH)-positive cells and TH protein levels in the substantia nigra (SN) were significantly augmented, while alpha-Synuclein (α-Syn) declined. Iron content in SN was reduced, thioredoxin reductase (TrxR) activity was enhanced, and protein Nrf2, TrxR1, and GPX4 were upregulated. In vitro findings showed that Sal (25 µM, 50 µM, 100 µM) significantly restored cell viability, replenished GSH/GSSG ratio, and reduced MDA levels. Molecularly, Sal administration upregulated GPX4, HO-1, Nrf2, and TrxR1 expression, as well as enhanced mitochondrial membrane potential. Particularly, Sal treatment heightened Nrf2 protein entry to the nucleus and upregulated TrxR1 expression. The nuclear translocation of Nrf2 was reversed by Nrf2 inhibitor ML385. Meanwhile, The neuroprotective effect of Sal was reversed by ML385 and TrxR1 inhibitor Auranofin. Sal exhibits significant therapeutic potential in mitigating MPTP-induced PD in mice and MPP+-induced Dopaminergic (DA) neuron toxicity in SH-SY5Y cells, as it protects DA neurons while inhibiting ferroptosis. These outcomes are likely associated with the Nrf2/TrxR1/GPX4 pathway.
Background In our previous research, we demonstrated that emodin inhibits cardiac fibrosis through MTA3. However, the limited bioavailability of emodin has hindered its clinical translation. Aim To safely and effectively apply the pharmacology of emodin to disease treatment, a new emodin derivative (emodin succinyl ethyl ester) was synthesized through structural modification at the 3'-OH position. This study primarily focused on the favorable properties of the emodin derivative, including drug-likeness assessment, evaluation of anti-fibrotic abilities, and the molecular mechanism involving the MTA3 pathway. Methods Computational-aided drug design (CADD) was applied for drug-likeness evaluations, including the absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties of the emodin derivative, as well as molecular docking and molecular dynamics simulations. An experimental animal model of transverse aortic constriction (TAC)-induced cardiac fibrosis was established to compare the pharmacological effects of the emodin derivative versus emodin in the progression of cardiac fibrosis. Cardiac collagen deposition, morphological, and functional indices were collected via immunohistochemical staining and animal echocardiography, revealing that the emodin derivative possesses superior capability in inhibiting cardiac fibrosis and restoring MTA3 expression. Primary isolated cardiac fibroblasts were used as in vitro study subjects. The relationships between MTA3 and its upstream transcription factors were predicted through bioinformatics analysis of PROMO database and validated using CADD, chromatin Immunoprecipitation (ChIP), Luciferase reporter assays, and loss-of- and gain-of-function experiments. Results The emodin derivative demonstrates superior properties compared to emodin in terms of drug-likeness, anti-cardiac fibrosis effects, inhibition of cardiac fibroblast transdifferentiation, and restoration of MTA3 expression levels. Consistent with emodin, MTA3 mediates the inhibitory effects against cardiac fibroblast transdifferentiation of the emodin derivative. E2F1 was predicted and then verified as the transcriptional regulator and observed that E2F1 positively promoted the expression of α-SMA and COL1A2, negatively regulating its expression. Emodin and its derivatives were found to directly bind to the transcription site of E2F1, with the emodin derivative showing a more robust and stable binding property compared to emodin. The emodin derivative also reduced the expression of E2F1, and conversely, interfering with E2F1 similarly affected the inhibitory action of the emodin derivative on the transdifferentiation of cardiac fibroblasts. Conclusion This study demonstrated that emodin derivative exhibits superior drug-likeness properties and more potent inhibition of cardiac fibrosis compared to emodin, by directly targeting the transcriptional regulatory site of E2F1, disrupting its pro-fibrotic function, thereby restoring MTA3 expression and halting cardiac fibrosis progression. These findings advance emodin potential as a clinical therapy for cardiac fibrosis and provide insights into its molecular mechanisms of anti-fibrotic action.
Background Anomalies in regional homogeneity (ReHo) have been documented in patients with major depressive disorder (MDD) and sleep disturbances (SDs). This investigation aimed to scrutinize changes in ReHo in MDD patients with comorbid SD, and to devise potential diagnostic biomarkers for detecting sleep-related conditions in patients with MDD. Methods Patients with MDD and healthy controls underwent resting-state functional magnetic resonance imaging scans. SD severity was quantified using the 17-item Hamilton Rating Scale for Depression. Subsequent to the acquisition of imaging data, ReHo analysis was performed, and a support vector machine (SVM) method was employed to assess the utility of ReHo in discriminating MDD patients with SD. Results Compared with MDD patients without SD, MDD patients with SD exhibited increased ReHo values in the right posterior cingulate cortex (PCC)/precuneus, right median cingulate cortex, left postcentral gyrus (postCG), and right inferior temporal gyrus (ITG). Furthermore, the ReHo values in the right PCC/precuneus and ITG displayed a positive correlation with clinical symptoms across all patients. SVM classification results showed that a combination of abnormal ReHo in the left postCG and right ITG achieved an overall accuracy of 84.21%, a sensitivity of 81.82%, and a specificity of 87.50% in identifying MDD patients with SD from those without SD. Conclusion We identified disrupted ReHo patterns in MDD patients with SD, and presented a prospective neuroimaging-based diagnostic biomarker for these patients.
Emerging studies have clarified the critical role of LncRNA MALAT1 in various pathological progressions. Here, we identified its positive relationship with cervical carcinoma proliferation. Cervical carcinoma has been considered as one of the most malignant tumors among female. Thus, our study was designed to investigate the underlying mechanism of LncRNA MALAT1 on cervical tumor cell proliferation. We observed that miR-124 was the potential target of LncRNA MALAT1 in cervical tumor cell lines (Hela, C-33A, Caski, and SiHa), the expression level of which is negatively correlated with LncRNA MALAT1 in cervical tumor cells, tissues of cervical patients, and mice. Gain- or loss-of-function analyses in cervical tumor cells have further verified the regulatory role of MALAT1 on miR-124. Additionally, the proliferation of cervical carcinoma was inhibited by miR-124 overexpression, whereas it was blocked by LV-MALAT1 transfection. In vivo assays, overexpression of miR-124, or knockdown of MALAT1 exhibited beneficial effects on tumor weight, size, and volume, together with elevating the survival rate, tightly related with the progression of cervical cancer. In conclusion, LncRNA MALAT1 disabled the effects of miR-124 as an inhibitory sponge, accelerating the progression of cervical carcinoma.
MicroRNAs (miRNAs) play an important role in cardiac function and metabolism. However, whether they regulate insulin resistance (IR) of cardiomyocytes remains unclear. The aim of the present study was to shed light on this issue with a focus on miR-150. We found here that miR-150 level was elevated in myocardium of type 2 diabetes mellitus (T2DM) rat model and in insulin-resistant cardiomyocytes induced by high glucose (25 mM) and high insulin (1 μM). Deregulation of miR-150 downregulated the protein and mRNA levels of glucose transporter 4 (GLUT4) as assessed by western blot, real-time polymerase chain reaction (qPCR), and immunofluorescence assays. Overexpression of miR-150 inhibited glucose utilization in cardiomyocytes as detected by 2-deoxyglucose transport and glucose consumption assays. In contrast, knockdown of miR-150 significantly increased glucose uptake in cardiomyocytes. Moreover, GLUT4 translocation was increased after transfection of miR-150 inhibitor (AMO-150). Collectively, miR-150 reduced glucose utilization by directly decreasing the expression and translocation of GLUT4 in the cardiomyocytes with IR and therefore might be a new therapeutic target for metabolic diseases such as T2DM.
Rationale: Nicotine exposure via cigarette smoking is strongly associated with atherosclerosis. However, the underlying mechanisms remain poorly understood. The current study aimed to identify whether endothelial to mesenchymal transition (EndMT) contributes to nicotine-induced atherosclerosis. Methods: ApoE-/- mice were administered nicotine in their drinking water for 12 weeks. The effects of nicotine on EndMT were determined by immunostaining on aortic root and RNA analysis in aortic intima. In vitro nicotine-treated cell model was established on human aortic endothelial cells (HAECs). The effects of nicotine on the expression of EndMT-related markers, ERK1/2 and Snail were quantified by real-time PCR, western blot and immunofluorescent staining. Results: Nicotine treatment resulted in larger atherosclerotic plaques in ApoE-/- mice. The vascular endothelial cells from nicotine-treated mice showed mesenchymal phenotype, indicating EndMT. Moreover, nicotine-induced EndMT process was accompanied by cytoskeleton reorganization and impaired barrier function. The α7 nicotine acetylcholine receptor (α7nAChR) was highly expressed in HAECs and its antagonist could effectively relieve nicotine-induced EndMT and atherosclerotic lesions in mice. Further experiments revealed that ERK1/2 signaling was activated by nicotine, which led to the upregulation of Snail. Blocking ERK1/2 with inhibitor or silencing Snail by small interfering RNA efficiently preserved endothelial phenotype upon nicotine stimulation. Conclusion: Our study provides evidence that EndMT contributes to the pro-atherosclerotic property of nicotine. Nicotine induces EndMT through α7nAChR-ERK1/2-Snail signaling in endothelial cells. EndMT may be a therapeutic target for smoking-related endothelial dysfunction and cardiovascular disease.
Excess activation of cardiac fibroblasts inevitably induces cardiac fibrosis. Emodin has been used as a natural medicine against several chronic diseases. The objective of this study is to determine the effects of emodin on cardiac fibrosis and the underlying molecular mechanisms. Intragastric administration of emodin markedly decreased left ventricular wall thickness in a mouse model of pathological cardiac hypertrophy with excess fibrosis induced by transaortic constriction (TAC) and suppressed activation of cardiac fibroblasts induced by angiotensin II (AngII). Emodin upregulated expression of metastasis associated protein 3 (MTA3) and restored the MTA3 expression in the setting of cardiac fibrosis. Moreover, overexpression of MTA3 promoted cardiac fibrosis; in contrast, silence of MTA3 abrogated the inhibitory effect of emodin on fibroblast activation. Our findings unraveled the potential of emodin to alleviate cardiac fibrosis via upregulating MTA3 and highlight the regulatory role of MTA3 in the development of cardiac fibrosis.
BACKGROUND:Vascular aging has profound effects on cardiovascular diseases. Endothelial to mesenchymal transition (EndMT) is defined as the acquisition of mesenchymal characteristics by endothelial cells (ECs) and has been found induced in a model of ECs aging. However, whether EndMT occurs during aging in vivo, the functional significance of EndMT on vascular biology and the underlying mechanisms remain unknown.METHODS AND RESULTS:In this study, we examined the vascular ECs from young (2 months old) and old (18 months old) mice, and demonstrated that aged ECs underwent EndMT. Moreover, the transwell assay showed that EndMT process was accompanied by increased endothelial permeability. It was found that sirtuin 6 (SIRT6), a nicotinamide adenine dinucleotide+ (NAD+)-dependent histone deacetylase, was down-regulated during ECs aging. Knockdown of SIRT6 in young ECs could induce EndMT. Next, we identified five long non-coding RNAs that are enriched in ECs for downstream effector of SIRT6; only metastasis associated lung adenocarcinoma transcript 1 (MALAT1) was significantly up-regulated in aged ECs. Knockdown of SIRT6 could increase MALAT1 levels. Furthermore, the ChIP assay and luciferase reporter gene assay confirmed that SIRT6 bound directly to the promoter region of MALAT1 and suppressed MALAT1 expression. Finally, we demonstrated that MALAT1 mediated aging-induced EndMT through increasing Snail expression.CONCLUSION:Our study provides in vivo evidence that ECs undergo EndMT during vascular aging, which increases endothelial permeability. SIRT6-mediated transcriptional suppression of MALAT1 is a key mechanism for EndMT. Manipulating EndMT may be considered as a new therapeutic strategy for retarding aging-associated vascular diseases.
OBJECTIVES:Metoprolol is regarded as a first-line medicine for the treatment of myocardial infarction (MI). However, the underlying mechanisms remain largely unknown. This study aimed to investigate the involvement of miR-1 in the pharmacological function of metoprolol.METHODS:In vivo MI model was established by left anterior descending coronary artery (LAD) ligation. The effects of metoprolol on infarct size and cardiac dysfunction were determined by triphenyltetrazolium chloride staining and cardiac echocardiography, respectively. In vitro oxidative stress cardiomyocyte model was established by H2 O2 treatment. The effect of metoprolol on the expression of miR-1 and connexin43 (Cx43) was quantified by real-time PCR and western blot, respectively. The intercellular communication was evaluated by lucifer yellow dye diffusion.KEY FINDINGS:Left anterior descending ligation-induced MI injury was markedly attenuated by metoprolol as shown by reduced infarct size and better cardiac function. Metoprolol reversed the up-regulation of miR-1 and down-regulation of Cx43 in MI heart. Moreover, in H2 O2 -stimulated cardiomyocytes, overexpression of miR-1 abolished the effects of metoprolol on Cx43 up-regulation and increased intercellular communication, indicating that miR-1 may be a necessary mediator for the cardiac protective function of metoprolol.CONCLUSIONS:Metoprolol relieves MI injury via suppression miR-1, thus increasing its target protein Cx43 and improving intercellular communication.
Background: Emerging evidence has indicated the therapeutic potential of emodin with its multiple pharmacological effects. Purpose: To evaluate role of emodin in regulating insulin resistance (IR) and to elucidate the underlying molecular mechanisms. Study design/Methods: Fasting blood glucose (FBG) and lipid levels were measured before and after intragastric administration of emodin in type 2 diabetes mellitus (T2DM) rats. Glucose consumption was determined in L6 cells to investigate the effect of emodin on glucose metabolism. Expression of miR-20b and SMAD7 was quantified by real-time PCR for mRNAs or western blot analysis for proteins. Results: Emodin ameliorated hyperglycemia and dyslipidemia in T2DM rats, and glucose metabolism in a concentration-and time-dependent manner. MiR-20b was markedly upregulated in the setting of IR and overexpression of miR-20b disrupted glucose metabolism by repressing SMAD7 in L6 cells. Knockdown of this miRNA produced the opposite effects. Emodin abolished the abnormal upregulation of miR-20b and indirectly upregulated SMAD7. Conclusion: Emodin improves glucose metabolism to produce anti-IR effects, and downregulation of miR-20b thereby upregulation of SMAD7 is an underlying mechanism for the beneficial effects of emodin.
Elimination of glucose transporter 4 (GLUT4) inevitably induces insulin resistance (IR), aggravating inflammation- and oxidative stress-related disorders. However, the underlying molecular mechanisms remain incompletely understood. In this study, we identified miR-17 as an important regulator of IR by targeting GLUT4. MiR-17 expression was found significantly elevated in skeletal tissues of rats with type 2 diabetes mellitus (T2DM), along with marked downregulation of GLUT4 protein level. Luciferase reporter gene assay demonstrated a direct interaction between miR-17 and the 3'untranslated region of GLUT4 mRNA. Correlation analyses (Spearman, Pearson, and Kendall) revealed that miR-17 level was negatively correlated with GLUT4 expression. Additionally, loss- and gain-of-function analyses showed that overexpression of miR-17 impaired glucose metabolism in L6 rat skeletal muscle cell line. In contrast, knockdown of endogenous miR-17 ameliorated glucose metabolism, accompanied by elevation of GLUT4 protein level. These findings unraveled a novel mechanism for IR that involves repression of GLUT4 by miR-17 and suggested miR-17 as a potential molecular target for the development of new therapeutic approaches for the treatment of T2DM.
Background/Aims: Type 2 Diabetes Mellitus (T2DM) is characterized by insulin resistance (IR), but the underlying molecular mechanisms are incompletely understood. MicroRNAs (miRNAs) have been demonstrated to participate in the signalling pathways relevant to glucose metabolism in IR. The purpose of this study was to test whether the multiple-target anti-miRNA antisense oligonucleotides (MTg-AMO) technology, an innovative miRNA knockdown strategy, can be used to interfere with multiple miRNAs that play critical roles in regulating IR. Methods: An MTg-AMO carrying the antisense sequences targeting miR-106b, miR-27a and miR-30d was constructed (MTg-AMO106b/27a/30d). Protein levels were determined by Western blot analysis, and transcript levels were detected by real-time RT-PCR (qRT-PCR). Insulin resistance was analysed with glucose consumption and glucose uptake assays. Results: We found that the protein level of glucose transporter 4 (GLUT4), Mitogen-activated protein kinase 14 (MAPK 14), Phosphatidylinositol 3-kinase regulatory subunit beta (PI3K regulatory subunit beta) and mRNA level of Slc2a4 (encode GLUT4), Mapk14 (encode MAPK 14) and Pik3r2 (encode PI3K regulatory subunit beta) were all significantly down-regulated in the skeletal muscle of diabetic rats and in insulin-resistant L6 cells. Overexpression of miR-106b, miR-27a and miR-30d in L6 cells decreased glucose consumption and glucose uptake, and reduced the expression of GLUT4, MAPK 14 and PI3K regulatory subunit beta. Conversely, silencing of endogenous miR-106b, miR-27a and miR-30d in insulin-resistant L6 cells enhanced glucose consumption and glucose uptake, and increased the expression of GLUT4, MAPK 14 and PI3K regulatory subunit beta. MTg-AMO106b/27a/30d up-regulated the protein levels of GLUT4, MAPK 14 and PI3K regulatory subunit beta, enhanced glucose consumption and glucose uptake. Conclusion: Our data suggested that miR-106b, miR-27a and miR-30d play crucial roles in the regulation of glucose metabolism by targeting the GLUT4 signalling pathway in L6 cells. Moreover, MTg-AMO106b/27a/30d offers more potent effects than regular singular AMOs.
Non-small cell lung cancer (NSCLC), one of the most common causes of cancer-related death, is a worldwide public health problem. MicroRNAs (miRNAs) have recently been identified as a novel class of regulators of carcinogenesis and tumor progression, including miRNAs associated with NSCLC. This study aimed to explore the role of miR-522 in NSCLC and the mechanisms underlying this role. We report here that miR-522 expression was significantly increased in both human NSCLC tissues and cell lines. Furthermore, an MTT assay, 5-Ethynyl-2'-deoxyuridine (EdU) assay kit and flow cytometry confirmed that the inhibition of miR-522 suppressed NSCLC cells proliferation and induced apoptosis. Compared with miR-522 overexpression, miR-522 inhibitor markedly reduced cells migration and invasion, as indicated by wound-healing and transwell assays. In addition, a luciferase assay identified DENN/MADD domain containing 2D (DENND2D) as a direct target of miR-522. qRT-PCR and western blot analyses indicated the reciprocal expression of miR-522 and DENND2D in NSCLC tissue samples. DENND2D was involved in miR-522 induced proliferation and metastasis of NSCLC cells by a miRNA-masking antisense oligonucleotides (miR-mask) technology. These data highlight a novel molecular interaction between miR-522 and DENND2D, which indicates that targeting miR-522 may constitute a potential therapy for NSCLC.
Atherosclerosis, a chronic inflammatory disease, is the major cause of life-threatening complications such as myocardial infarction and stroke. Endothelial apoptosis plays a vital role in the initiation and progression of atherosclerotic lesions. Although a subset of microRNAs (miRs) have been identified as critical regulators of atherosclerosis, studies on their participation in endothelial apoptosis in atherosclerosis have been limited. In our study, we found that miR-26a expression was substantially reduced in the aortic intima of ApoE−/− mice fed with a high-fat diet (HFD). Treatment of human aortic endothelial cells (HAECs) with oxidized low-density lipoprotein (ox-LDL) suppressed miR-26a expression. Forced expression of miR-26a inhibited endothelial apoptosis as evidenced by MTT assay and TUNEL staining results. Further analysis identified TRPC6 as a target of miR-26a and TRPC6 overexpression abolished the anti-apoptotic effect of miR-26a. Moreover, the cytosolic calcium and the mitochondrial apoptotic pathway were found to mediate the beneficial effects of miR-26a on endothelial apoptosis. Taken together, our study reveals a novel role of miR-26a in endothelial apoptosis and indicates a therapeutic potential of miR-26a for atherosclerosis associated with apoptotic cell death.
Streptococcosis became an increasingly significant health problem in intensive aquaculture in China. In 2009, eight Gram-positive, chain-forming coccus strains were isolated from the outbreak epidemical diseased tilapias from Hainan Province, China. Characteristics based on morphological, physiological and biochemical tests show that the eight strains were suggested to Streptococcus agalactiae. Furthermore, sequencing of the 16S rRNA genes shows high sequence similarities (99.5 to 99.9%) with S. agalactiae. All results indicated that the eight isolated strains (Genbank no JF423941~JF423948) were S. agalactiae. The median lethal doses (LD50) of HN0101 and HN0301 which were isolated from Wenchang and Xinglong villages were 6.8×106 and 5.3×106 CFU/fish, respectively by intraperitoneal injections. All the isolates were sensitive to cefoxitin, and had quite different sensitiveness to other antibiotics. This research hinted that S. agalactiae had become an important potential bacterial agent of tilapias in the south of China. Key words: Streptococcus agalactiae, tilapia, identification
The stamping technique of a lantern ring was analyzed.A progressive drawing die for forming the part was developed and the process calculation,layout design and structure design of the die were introduced,in which CATIA parameterized modeling method and measurement of process data were applied.