TdT) dUTP Nick-end Labeling Research Articles

The impact of crowding stress on growth and intestinal integrity in largemouth bass (Micropterus salmoides): Insights into ER stress, autophagy and apoptosis

Crowding stress is a common abiotic stressor in intensive aquaculture that negatively impacts fish species, leading to growth depression. This study primarily explored the effects of crowding stress on the growth and intestinal integrity of largemouth bass (Micropterus salmoides). A 10-week feeding experiment was conducted with two groups: a control group (0.55 kg/m³) and a crowding stress group (1.10 kg/m³). The results showed that crowding stress significantly impaired fish growth and compromised intestinal integrity. To further elucidate the underlying mechanisms, we investigated the effects of crowding stress on endoplasmic reticulum (ER) stress, autophagy and apoptosis. Our findings revealed an increased proportion of terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL)-positive cells and ER swelling in the intestines of stressed fish, along with a higher number of autophagosomes. Furthermore, there was a significant upregulation in the mRNA expression of genes related to ER stress, autophagy and apoptosis, including GRP78, eIF2α, IRE1, atg3, LC3-2, ulk1α, P62, and caspase-8. In conclusion, crowding stress negatively affects fish growth and intestinal integrity, potentially through the induction of apoptosis and autophagy associated with ER stress-mediated unfolded protein response (UPR). These findings provided critical insights into how intensive aquaculture disrupts intestinal integrity and inhibits growth in fish, offering a valuable reference for future research aimed at enhancing stress resistance in fish under intensive aquaculture conditions.

Propofol Ameliorates Sepsis-Induced Myocardial Dysfunction via Anti-Apoptotic, Anti-Oxidative Properties, and mTOR Signaling.

Sepsis often leads to cardiomyopathy, contributing to increased mortality rates. 2,6-Diisopropylphenol (propofol), an anesthetic, has demonstrated efficacy in protecting cardiomyocytes from cell death caused by hypoxia and reoxygenation. This study examined the effects of propofol on sepsis-associated myocardial dysfunction and explored the underlying mechanism of action. Mice and rat cardiomyocytes (H9C2 cell line) were used to establish a sepsis-induced myocardial dysfunction model. Lipopolysaccharides (LPS)-treated mice and H9C2 cells were treated with propofol, with rapamycin used for mechanistic studies in H9C2 cells. Cardiac function was evaluated by echocardiographic measurements. Heart tissues were stained with hematoxylin and eosin, and heart weight/body weight ratio along with the levels of cardiac biomarkers were measured using Enzyme Linked Immunosorbent Assay (ELISA). Activation of the mammalian target of rapamycin (mTOR) pathway was assessed by western blotting. Apoptosis in heart tissues and H9C2 cells was evaluated using Terminal deoxynucleotidyl transferase (TdT) dUTP nick end labeling (TUNEL) assay, and cell viability was quantified using Cell Counting Kit (CCK)-8 assay. Oxidative stress in H9C2 cells was assessed by measuring reactive oxygen species (ROS) levels through immunofluorescence staining and malondialdehyde (MDA) and superoxide dismutase (SOD) levels using ELISA. Propofol reversed LPS-induced myocardial changes and cardiac dysfunction (p < 0.05). In mouse tissues and H9C2 cells, propofol reversed LPS-induced mTOR pathway inhibition and apoptosis (p < 0.001). Moreover, propofol alleviated oxidative stress in LPS-treated cells. The activation of the mTOR pathway by propofol, along with its inhibitory effects on oxidative stress and apoptosis in cardiomyocytes, was negated by rapamycin (p < 0.001). Propofol ameliorates sepsis-induced myocardial dysfunction triggered by LPS through the mTOR pathway, thereby promoting antioxidative stress and reducing cell apoptosis.

PCGF2 Acts as an Oncogenic Driver in Colon Cancer through the Upregulation of CENPE.

Colon cancer (CC) is a highly prevalent malignancy that contributes significantly to global morbidity and mortality. The polycomb group ring finger 2 (PCGF2) has been identified as a relevant factor influencing the outcomes of CC. At the same time, the centromere-associated protein E (CENPE) is implicated in promoting carcinogenesis and adversely affecting the survival of tumor patients. The primary objective of this study was to elucidate the precise impact of PCGF2 on CC and unravel the underlying mechanisms associated with CENPE. Human normal colon epithelial cells and CC cells were utilized to investigate the differential expression of PCGF2 and CENPE. CC cell line LOVO was exploited and transfected for PCGF2 regulation. Subsequently, cell viability and proliferation were assessed using the cell counting kit 8 (CCK-8) and colony forming assay. Cell viability and proliferation were assessed using the terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) assay, while cell migration and invasion capabilities were determined using the transwell assay, and mRNA levels of cell cycle-related genes were measured for evaluating cell cycle activation. In addition, mice were used for in vivo experiments to investigate the progression of CC cells with different levels of PCGF2. Moreover, GSK-923295 was used to inhibit CENPE, followed by the evaluation of cell progression. PCGF2 and CENPE were upregulated in CC cell lines (p < 0.001), and upregulation/downregulation of PCGF2 led to the upregulation and downregulation of CENPE (p < 0.001). The upregulation/downregulation of PCGF2 led to an increase/decrease in viability, proliferation, migration, and invasion while suppressing/enhancing apoptosis in LOVO cells (p < 0.001), promoting cell progression. The tumor progression of LOVO cells with PCGF2 knockdown was slower (p < 0.001). The PCGF2-promoting LOVO cell progression was disrupted when CENPE was inhibited, presented by the reversely decreased viability, proliferation, migration, invasion, and cell cycle activation, and increased apoptosis (p < 0.001). PCGF2 promotes CC cell progression by upregulating CENPE, providing PCGF2 inhibition and CENPE inhibition as potential therapeutic targets for treating CC.

Quercetin Protects Against Hypertensive Renal Injury by Attenuating Apoptosis: An Integrated Approach Using Network Pharmacology and RNA Sequencing.

Quercetin is known for its antihypertensive effects. However, its role on hypertensive renal injury has not been fully elucidated. In this study, hematoxylin and eosin staining, terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining, and Annexin V staining were used to assess the pathological changes and cell apoptosis in the renal tissues of angiotensin II (Ang II)-infused mice and Ang II-stimulated renal tubular epithelial cell line (NRK-52E). A variety of technologies, including network pharmacology, RNA-sequencing, immunohistochemistry, and Western blotting, were performed to investigate its underlying mechanisms. Network pharmacology analysis identified multiple potential candidate targets (including TP53, Bcl-2, and Bax) and enriched signaling pathways (including apoptosis and p53 signaling pathway). Quercetin treatment significantly alleviated the pathological changes in renal tissues of Ang II-infused mice and reversed 464 differentially expressed transcripts, as well as enriched several signaling pathways, including those related apoptosis and p53 pathway. Furthermore, quercetin treatment significantly inhibited the cell apoptosis in renal tissues of Ang II-infused mice and Ang II-stimulated NRK-52E cells. In addition, quercetin treatment inhibited the upregulation of p53, Bax, cleaved-caspase-9, and cleaved-caspase-3 protein expression and the downregulation of Bcl-2 protein expression in both renal tissue of Ang II-infused mice and Ang II-stimulated NRK-52E cells. Moreover, the molecular docking results indicated a potential binding interaction between quercetin and TP53. Quercetin treatment significantly attenuated hypertensive renal injury and cell apoptosis in renal tissues of Ang II-infused mice and Ang II-stimulated NRK-52E cells and by targeting p53 may be one of the potential underlying mechanisms.

Mechanisms of Yiai Fuzheng formula in the treatment of triple-negative breast cancer based on UPLC-Q-Orbitrap-HRMS, network pharmacology, and experimental validation

Ethnopharmacological relevanceYiai Fuzheng formula (YAFZF), as a Traditional Chinese Medicine (TCM) prescription, has been used widely at Zhongnan Hospital of Wuhan University for its therapeutic effects and high safety on triple-negative breast cancer (TNBC). ObjectiveIn this study, we employed ultra-high-performance liquid chromatography-quadrupole/orbitrap high-resolution mass spectrometry (UPLC-Q-Orbitrap-HRMS), network pharmacology, and experimental validation to elucidate the underlying action mechanism of YAFZF in the treatment of TNBC. MethodsThe key active ingredients in YAFZF were analyzed using UPLC-Q-Orbitrap-HRMS, and then the potential components, target genes and signalling pathways of YAFZF were predicted using the network pharmacological method. We then used molecular docking to visualize the combination characteristics between major active components and macromolecules in the crucial pathway. In vitro experiments were conducted to investigate the inhibitory effects of YAFZF treatment on the cell viability, invasion, and migration of 4T1 and MDA-MB-231 cells. The xenograft TNBC models were constructed using female Balb/c mice, and their body weights, tumour volumes, and weights were monitored during YAFZF treatment. Quantitative real-time PCR (qRT-PCR), Hematoxylin-eosin (HE), immunohistochemistry (IHC) staining, Western blot (WB), and terminal deoxynucleotidyl transferase (TdT)-dUTP nick-end labeling (TUNEL) staining were used for further experimental validation. ResultsBased on UPLC-Q-Orbitrap-HRMS and network pharmacology analysis, 6 major bioactive components and 153 intersecting genes were obtained for YAFZF against TNBC. Functional enrichment analysis identified that the phosphatidylinositol 3-kinase (PI3K)-protein kinase B (Akt) signalling pathway might be the mechanism of action of YAFZF in the treatment of TNBC. Molecular docking results suggested that the main active compounds in YAFZF had strong binding energies with the proteins in the PI3K/Akt pathway. In vitro experiments showed that YAFZF inhibited the cell viability, invasion, and migration abilities of TNBC cells. Animal experiments confirmed that YAFZF treatment suppressed tumour cell proliferation and increased apoptotic cells. PCR, HE, WB, and IHC results indicated that YAFZF could suppress xenograft tumour metastases by inhibiting the PI3K/AKT/mTOR pathway regulating the epithelial-mesenchymal transition (EMT) process. ConclusionYAFZF therapy showed its potential for reducing proliferation, invasion, and migration abilities, increasing apoptosis of TNBC cells. Furthermore, YAFZF treated TNBC by inhibiting xenograft tumour distant metastases via the regulation of EMT by the PI3K/Akt/mTOR pathway, suggesting that it may be useful as an adjuvant treatment.

MiR-33a Overexpression Exacerbates Diabetic NephropathyThrough Sirt6-dependent Notch Signaling.

Diabetic nephropathy (DN) belongs to the major cause of end-stage kidney disease. We probed the functions of a microRNA miR-33a in inducing podocytes injury during childhood DN (CDN). Kidney samples were collected from 20 children with DN. Matrix deposition and glomerular basement membranes thickness were examined by periodic acid-Schiff staining. Immunofluorescence staining was performed to assess kidney function-related proteins. MicroRNA (MiR)-33a mimic together with miR-33a inhibitor was transfected into podocytes for determining the roles of miR-33a. Glomerular podocyte apoptosis was determined by terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) staining along with flow cytometry. Down-regulation of Nephrin and Podocin and increased podocyte apoptosis rate were observed in the glomerulus of CDN as well as podocytes treated with high glucose. MiR-33a was up regulated in the glomeruli and glucose-treated podocytes. Injury in podocytes was aggravated with miR-33a elevation but alleviated with miR-33a inhibition. Moreover, the expression of Sirtuin 6 (Sirt6) was decreased while the levels of notch receptor 1 (Notch1) and notch receptor 4 (Notch4) were elevated in the glomerulus and glucose-treated podocytes. Decreased level of Sirt6 upon glucose treatment was abrogated by miR-33a inhibition, and the podocytes injury induced by glucose exposure was relieved by Sirt6 via Notch signaling. These findings indicated that miR-33a promoted podocyte injury via targeting Sirt6-dependent Notch signaling in CDN, which might provide a novel sight for CDN treatment. DOI: 10.52547/ijkd.7904.

Human Mesenchymal Stem Cells Improve Angiogenesis and Bone Formation in Severed Finger Rats through SIRT1/Nrf2 Signaling.

This study employed a severed finger rat model to analyze the effects of human mesenchymal stem cells (MSCs) on angiogenesis, inflammatory response, apoptosis, and oxidative stress, to evaluate the possible mechanism of the repair effect of MSCs on severed finger (SF) rats. Sixty Sprague-Dawley (SD) rats were categorized into five groups (n = 12). The pathological changes of severed finger tissues were investigated by Hematoxylin and eosin (H&E) staining on day 14 after the rats were sacrificed. The levels of inflammatory factors and oxidative stress factors were detected by ELISA. Terminal Deoxynucleotidyl Transferase (TdT) dUTP Nick End Labeling (TUNEL) was employed to assess the apoptosis of chondrocytes in severed finger tissues. The expression of osteocalcin (OCN), osteopontin (OPN), Collagen I (Col-1), and CD31 were detected by immunohistochemistry or immunofluorescence assay, respectively. The expression levels of related proteins were determined by western blot. Our study presented evidence that MSCs treatment improved pathological changes of skin and bone tissue, diminished the inflammatory response, prevented oxidative stress injury, suppressed chondrocyte apoptosis, and promoted angiogenesis, and bone formation compared to the model group. In addition, EX527 treatment attenuated the effect of MSCs, SRT1720 and ML385 co-treatment also attenuated the effect of MSCs. Importantly, the MSCs treatment increased the expression of Sirtuin 1(SIRT1)/Nuclear factor erythroid2-related factor 2(Nrf2) relate proteins. Our study indicated that the mechanism of the effect of MSCs on a severed finger was related to the SIRT1/ Nrf2 signaling pathway.

ATF4 Exacerbates Cerebral Infarction-Induced Sensory Dysfunction via HDAC1/DNMT1/GPX4 Signaling.

Cerebral infarction is the main cause of death and long-term disability worldwide. Neuronal degeneration and limp sensory dysfunction are the secondary damages induced by cerebral infarction. This study aimed to investigate the roles of activating transcription factor 4 (ATF4) in cerebral infarction and the underlying molecular mechanisms. Middle cerebral artery occlusion (MCAO) surgery was applied to establish a cerebral infarction model in vivo. Histological analysis was performed using Nissl assay. Gene expression was determined using immunohistochemistry, immunofluorescence, and Western blot. Gene interaction was confirmed by co-immunoprecipitation (Co-IP), chromatin immunoprecipitation (ChIP), and luciferase assays. Cellular functions were determined using Cell Counting Kit assay (CCK-8), propidium iodide (PI) staining, and terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) assays. ATF4 was overexpressed in cerebral infarction models in vivo and in vitro. However, ATF4 knockdown decreased ischemic foci and volume and restored sensory functions in vivo. ATF4 knockdown suppressed lipid peroxidation and neuronal ferroptosis in vitro. Moreover, ATF4 activated DNA methyltransferase 1 (DNMT1), which induced glutathione peroxidase 4 (GPX4) DNA methylation and decreased its expression. GPX4 knockdown alleviated the effects of shATF4 and promoted neuronal ferroptosis. Overall, ATF4 knockdown protected against cerebral infarction and sensory dysfunction by promoting DNMT1-mediated DNA methylation of GPX4.

Notoginsenoside R1 attenuates brain injury in rats with traumatic brain injury: Possible mediation of apoptosis via ERK1/2 signaling pathway.

Traumatic brain injury (TBI) occurs worldwide and is associated with high mortality and disability rate. Apoptosis induced by TBI is one of the important causes of secondary injury after TBI. Notoginsenoside R1 (NGR1) is the main phytoestrogen extracted from Panax notoginseng. Many studies have shown that NGR1 has potent neuroprotective, anti-inflammatory, and anti-apoptotic properties and is effective in ischemia-reperfusion injury. Therefore, we investigated the potential neuroprotective effects of NGR1 after TBI and explored its molecular mechanism of action. A rat model of TBI was established using the controlled cortical impact (CCI) method. The expression levels of Bcl-2, Bax, caspase 3, and ERK1/2-related molecules in the downstream pathway were also detected by western blotting. The expression levels of pro-inflammatory cytokines were detected by real-time quantitative PCR. Nissl staining was used to clarify the morphological changes around the injury foci in rats after TBI. Fluoro-Jade B (FJB) and terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) fluorescence staining were used to detect the apoptosis of neural cells in each group of rats. The results showed that NGR1 administration reduced neurological deficits after TBI, as well as brain edema and brain tissue apoptosis. It also significantly inhibited the expression of pro-inflammatory cytokines. Furthermore, NGR1 decreased the expression levels of extracellular signal-regulated kinase (ERK) and p-RSK1, which are phosphorylated after trauma. This study suggests that NGR1 can improve neuronal apoptosis in brain injury by inhibiting the ERK signaling pathway. NGR1 is a potential novel neuroprotective agent for the treatment of secondary brain injury after TBI.

Effects of Vitamin D on Asprosin Immunoreactivity Against Cyclophosphamide-Induced Liver Injury in Rats.

Background Cyclophosphamide (CP), commonly used as an anticarcinogenic drug, has the potential to induce detrimental effects on multiple tissues, including the liver. Asprosin, which is a glucogenic adipokine, induces the liver to secrete glucose, thus contributing to the maintenance of homeostasis. This study aims to investigate the immunoreactivity of asprosin in the liver tissue of rats exposed to CP administration, as well as the changes in its levels due to the supplementation of Vitamin D (Vit D). Materials and methods Four experimental groups were formed, including control, Vit D (200 IU/kg), CP (200 mg/kg), and Vit D+ CP. Histopathological analysis was carried out by employing staining methods on liver tissues. These techniques encompassed the application of hematoxylin-eosin (H&E), Masson's trichrome, and periodic acid Schiff (PAS). Through the application of spectrophotometric methods,concentrations of malondialdehyde (MDA), total antioxidant status (TAS), total oxidant status (TOS), and asprosin were determined. Furthermore, apoptotic cells were identified by the terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) method, and the asprosin immunoreactivity was determined by immunohistochemistry. Results Under light microscope examination, the histopathological damage was found to be more notable in the CP group compared to the control group. Moreover, a decrease was observed in serum and tissue asprosin levels, while an increase was noted in the count of apoptotic cells, along with elevated MDA and TOS levels. However, in the CP+Vit D group, Vit D administration alleviated histopathological damage. Notably, there were significant increases in TAS and asprosin levels, accompanied by reductions in both MDA and TOS levels. Conclusions The effect of CP on liver tissue was observed to result in damage and a reduction in asprosin levels. Vit D supplementation revealed elevated asprosin levels and a distinct protective effect on the tissue. Considering the association between asprosin and liver injury induced by CP, further research is needed to elucidate the mechanisms that underlie the effect of asprosin on tissues. When combined with VitD, asprosin holds promise for potential clinical applications as a therapeutic target.

The Apoptotic and Anti-Warburg Effects of Brassinin in PC-3 Cells via Reactive Oxygen Species Production and the Inhibition of the c-Myc, SIRT1, and β-Catenin Signaling Axis.

Though Brassinin is known to have antiangiogenic, anti-inflammatory, and antitumor effects in colon, prostate, breast, lung, and liver cancers, the underlying antitumor mechanism of Brassinin is not fully understood so far. Hence, in the current study, the apoptotic mechanism of Brassinin was explored in prostate cancer. Herein, Brassinin significantly increased the cytotoxicity and reduced the expressions of pro-Poly ADP-ribose polymerase (PARP), pro-caspase 3, and B-cell lymphoma 2 (Bcl-2) in PC-3 cells compared to DU145 and LNCaP cells. Consistently, Brassinin reduced the number of colonies and increased the sub-G1 population and terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL)-positive cells in the PC-3 cells. Of note, Brassinin suppressed the expressions of pyruvate kinase-M2 (PKM2), glucose transporter 1 (GLUT1), hexokinase 2 (HK2), and lactate dehydrogenase (LDH) as glycolytic proteins in the PC-3 cells. Furthermore, Brassinin significantly reduced the expressions of SIRT1, c-Myc, and β-catenin in the PC-3 cells and also disrupted the binding of SIRT1 with β-catenin, along with a protein-protein interaction (PPI) score of 0.879 and spearman's correlation coefficient of 0.47 being observed between SIRT1 and β-catenin. Of note, Brassinin significantly increased the reactive oxygen species (ROS) generation in the PC-3 cells. Conversely, ROS scavenger NAC reversed the ability of Brassinin to attenuate pro-PARP, pro-Caspase3, SIRT1, and β-catenin in the PC-3 cells. Taken together, these findings support evidence that Brassinin induces apoptosis via the ROS-mediated inhibition of SIRT1, c-Myc, β-catenin, and glycolysis proteins as a potent anticancer candidate.

GRP78 inhibitor HA15 increases the effect of Bortezomib on eradicating multiple myeloma cells through triggering endoplasmic reticulum stress

Bortezomib (BTZ), a selective proteasome inhibitor, exhibits a significant efficacy in the therapy of multiple myeloma (MM) partly through triggering endoplasmic reticulum (ER) stress-dependent apoptosis. However, sensitivity to BTZ varies greatly among patients. ER stress functions as a double-edged sword in regulating cell survival depending on cell context and ER stress extent. The major aim of this study was to investigate whether GRP78 inhibitor, HA15, increased the therapeutic effect of BTZ on MM to through further increasing ER stress and shifting the balance towards cell apoptosis. The biological role of BTZ and HA15 was assessed using Cell counting kit- (CCK-) 8, colony formation, and Terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labelling (TUNEL) assay. We found that BTZ combined with HA15 remarkably decreased MM cell viability more effective than BTZ monotherapy, though low dose of HA15 did not exhibit a significant cytotoxicity to MM cells. BTZ combined with HA15 also repressed colony formation ability of MM cell and accelerated MM cell apoptosis compared with BTZ monotherapy. Mechanistically, HA15 synergized with BTZ to trigger ER stress, as evidence by significantly increased expression of ER stress markers (GRP78, ATF4, CHOP, and XBP1). Importantly, unfolded protein response (UPR) inhibitor significantly damaged the effect of BTZ combined with HA15 on accelerating MM cell death. In vivo, combination treatment with BTZ and HA15 inhibited tumor growth more effective than BTZ alone, whereas these effects were blocked by UPR inhibitor. Taken together, these results demonstrate that ER stress is a critical pathway in regulating MM cell survival, and that combination treatment with BTZ and HA15 may be an effective strategy to treat MM patients that fail to respond to BTZ monotherapy.

CISD2 transcriptional activated by transcription factor E2F7 promotes the malignant progression of cervical cancer.

Cervical cancer (CC) is the second most common type of cancer in women, and presents a serious threat to public health. We aimed to investigate the regulatory impacts of CDGSH iron-sulfur domain-containing protein 2 (CISD2) in CC and to discuss its relationship with E2F transcription factor 7 (E2F7). With the employment of real-time reverse transcriptase-polymerase chain reaction (RT-qPCR) and western blot, the expression of CISD2 and E2F7 in SiHa cells before or after transfection was estimated. Cell counting kit-8 (CCK-8) assay, Terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) assay, wound healing and transwell were used to detect the proliferation, apoptosis, migration and invasion of SiHa cells. The activity of CISD2 was detected using luciferase report assay and chromatin immunoprecipitation (ChIP) assay was used to confirm the binding of E2F7 and CISD2 promoter. The contents of proliferation- and apoptosis-related proteins were detected using western blot. Results revealed that CISD2 expression was greatly enhanced in CC cell lines. CISD2 depletion inhibited the proliferation, migration and invasion of SiHa cells but promoted the cell apoptosis. It was also found that E2F7 was remarkably elevated in SiHa cells. According to JASPAR database, the binding sites of E2F7 and CISD2 were predicted and ChIP confirmed the binding of E2F7 and CISD2 promoter. Results obtained from luciferase report assay indicated that E2F7 overexpression increased the activity of CISD2 promoter region. Furthermore, further functional experiments demonstrated that the impacts of E2F7 interference on the proliferation, migration, invasion and apoptosis of SiHa cells were reversed by CISD2 overexpression. In summary, CISD2 silence could alleviate the malignant progression of CC and could be transcribed by E2F7.

MiR-100-5p activation of the autophagy response through inhibiting the mTOR pathway and suppression of cerebral infarction progression in mice.

In recent years, the association between microRNAs (miRNAs) and autophagy in cerebral infarction (CI) has attracted increasingly more attention. The mammalian target of the rapamycin (mTOR) pathway is a key protein regulating the autophagy response. miR-100-5p can bind to the mTOR protein, but its role in CI remains unclear yet. This experiment aims to clarify the role of miR-100-5p in CI. Bioinformatics analysis was performed to screen differentiated expressed functional genes between CI tissue and normal tissue specimens. In vivo experiments: the mouse model of CI was established by middle cerebral artery occlusion (MCAO) methods, After being treated with miR-100-5p-overexpressing lentivirus, the amount of terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL)-positive fluorescence and the fluorescent expression level of mTOR protein were significantly inhibited in the CI region. Western blotting analysis showed that miR-100-5p inhibited the protein expression level of phosphorylated mTOR and total mTOR and enhanced the expression of autophagy-related proteins Beclin, microtubule-associated protein light chain 3II (LC-3II), and autophagy-related gene 7 (ATG-7). For in vitro experiment, after the BV-2 cells were successfully infected with the control lentivirus and miR-100-5p-overexpression lentivirus, they were stimulated with 1% hypoxia and low-glucose medium in a tri-gas incubator for 24 h. It was found that miR-100-5p could significantly lower the protein expression level of phosphorylated mTOR and total mTOR, and increase the expression of the Beclin, LC-3II, ATG-7 autophagy related proteins. miR-100-5p promotes the autophagy response through binding to mTOR protein, thereby inhibiting apoptosis and delaying the progression of CI.

Epigenetic regulatory mechanism of ADAMTS12 expression in osteoarthritis

BackgroundOsteoarthritis (OA) is a degenerative joint disease with lacking effective prevention targets. A disintegrin and metalloproteinase with thrombospondin motifs 12 (ADAMTS12) is a member of the ADAMTS family and is upregulated in OA pathologic tissues with no fully understood molecular mechanisms.MethodsThe anterior cruciate ligament transection (ACL-T) method was used to establish rat OA models, and interleukin-1 beta (IL-1β) was administered to induce rat chondrocyte inflammation. Cartilage damage was analyzed via hematoxylin-eosin, Periodic Acid-Schiff, safranin O-fast green, Osteoarthritis Research Society International score, and micro-computed tomography assays. Chondrocyte apoptosis was detected by flow cytometry and TdT dUTP nick-end labeling. Signal transducer and activator of transcription 1 (STAT1), ADAMTS12, and methyltransferase-like 3 (METTL3) levels were detected by immunohistochemistry, quantitative polymerase chain reaction (qPCR), western blot, or immunofluorescence assay. The binding ability was confirmed by chromatin immunoprecipitation-qPCR, electromobility shift assay, dual-luciferase reporter, or RNA immunoprecipitation (RIP) assay. The methylation level of STAT1 was analyzed by MeRIP-qPCR assay. STAT1 stability was investigated by actinomycin D assay.ResultsThe STAT1 and ADAMTS12 expressions were significantly increased in the human and rat samples of cartilage injury, as well as in IL-1β-treated rat chondrocytes. STAT1 is bound to the promoter region of ADAMTS12 to activate its transcription. METTL3/ Insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) mediated N6-methyladenosine modification of STAT1 promoted STAT1 mRNA stability, resulting in increased expression. ADAMTS12 expression was reduced and the IL-1β-induced inflammatory chondrocyte injury was attenuated by silencing METTL3. Additionally, knocking down METTL3 in ACL-T-produced OA rats reduced ADAMTS12 expression in their cartilage tissues, thereby alleviating cartilage damage.ConclusionMETTL3/IGF2BP2 axis increases STAT1 stability and expression to promote OA progression by up-regulating ADAMTS12 expression.

Assessment of cell-free DNA and apoptosis in an oocyte microenvironment: promising biomarkers to predict intracytoplasmic sperm injection outcomes.

Cell-free DNA (cf-DNA) is defined as DNA fragments that are released into the body fluids from apoptosis or necrosis cells, including follicular fluid (FF), which can affect the microenvironment of the oocyte associated with infertility. We aimed to investigate a relationship between apoptosis of cumulus cells (CCs) and cf-DNA levels in FF and clinical outcomes of women undergoing intracytoplasmic sperm injection (ICSI). Therefore, 82 FF samples were collected, and the corresponding CCs were isolated for ICSI procedures. FF cf-DNA concentration was quantified using ALU-quantitative polymerase chain reaction (PCR), and CCs DNA fragmentation index (DFI) was evaluated by the terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labelling (TUNEL) method. We found that cf-DNA and DFI levels were significantly higher in FF and CCs samples related to the age of women ≥37 years compared with the age of women < 37 years. Moreover, in older and younger women, FF cf-DNA and CCs DFI levels were significantly lower when the anti-Müllerian hormone (AMH) level was > 1.1 ng/ml compared with when AMH ≤ 1.1 ng/ml. In addition, patients with a low number of retrieved oocytes ≤ 6 had significantly higher levels of CCs DFI and FF cf-DNA than women with a higher number of retrieved oocytes > 6. Additionally, we observed that higher levels of cf-DNA and DFI were associated with poor oocyte maturity and poor embryo quality. Finally, cf-DNA and DFI levels were significantly lower in pregnant women than in non-pregnant ones. We conclude that DFI and cf-DNA levels in the oocyte microenvironment could have potential use in evaluating oocyte and embryo developmental competence.

CircSFMBT2-OA alleviates chondrocyte apoptosis and extracellular matrix degradation through repressing NF-κB/NLRP3 inflammasome activation

BackgroundIntra-articular inflammation and cartilage degradation are the major pathological characteristics of osteoarthritis (OA). Mounting studies have revealed that circular RNAs (circRNAs) act as an important regulatory role in inflammatory diseases and are frequently dys-expressed in OA cartilage tissues. ObjectiveHere, a dys-regulated cicrRNA (has_circ_0017636, termed circSFMBT2-OA) was identified, and its role in regulating lipopolysaccharide (LPS)-induced chondrocyte injury was next investigated. MethodsCHON-001 chondrocytes were treated with LPS, and then the levels of circSFMBT2-OA, cartilage-related genes, and pro-inflammatory cytokines were measured using quantitative real-time PCR (qRT-PCR) and Western blot analysis. CHON-001 cell viability, proliferation, and apoptosis were assayed using Cell Counting Kit-8 (CCK-8), 5-Ethynyl-2′-deoxyuridine (EDU), and terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) assay, respectively. ResultsCircSFMBT2-OA level was significantly down-regulated in OA cartilage tissues and LPS-treated CHON-001 cells. Functionally, circSFMBT2-OA overexpression accelerated cell proliferation, and suppressed cell apoptosis, pro-inflammatory cytokines production, matrix-degrading enzymes expression, and ECM degradation in CHON-001 cells. Inversely, circSFMBT2-OA depletion decreased cell viability and increased matrix-degrading enzymes expression and ECM degradation. Mechanistically, circSFMBT2-OA inhibited LPS-induced NF-κB/NOD-like receptor family pyrin domain containing protein 3 (NLRP3) inflammasome activation in CHON-001 cells. Consequently, NLRP3 activator reversed the effect of circSFMBT2-OA on repressing LPS-induced CHON-001 cell injury. ConclusionThese data reveal a vital effect of a novel circSFMBT2-OA on repressing OA progression and provide a promising target to treat OA.

Polydatin protects against atherosclerosis by activating autophagy and inhibiting pyroptosis mediated by the NLRP3 inflammasome.

Polydatin is a bioactive ingredient extracted from the roots of the Reynoutria japonica Houtt, and it is a natural precursor of resveratrol. Polydatin is a useful inhibitor of inflammation and acts as a regulator of lipid metabolism. However, the specific mechanisms of action of polydatin in atherosclerosis (AS) remains poorly explained. The aim of this study was to assess the efficacy of polydatin on inflammation induced by the inflammatory cell death and autophagy in AS. Apolipoprotein E knockout (ApoE-/-) mice were fed with a high-fat diet (HFD) for 12 weeks to induce the formation of atherosclerotic lesions. The ApoE-/- mice were then randomly divided into the following six groups: (1) model group, (2) simvastatin group, (3) MCC950 group, (4) low dose polydatin group (Polydatin-L), (5) medium dose polydatin group (Polydatin-M), (6) and high dose polydatin group (Polydatin-H). The C57BL/6J mice were treated as controls and administered a standard chow diet. All mice were gavaged once daily for 8 weeks. The distribution of aortic plaques was observed by En Oil-red-O staining and hematoxylin and eosin staining (H&E). Oil-red-O staining was used to observe lipid content in the aortic sinus plaque; Masson trichrome staining was used to gauge collagen content in the plaque; and immunohistochemistry was used to evaluate smooth muscle actin (α-SMA) and CD68 macrophages marker expression levels in the plaque, which were used to assess the vulnerability index of the plaque. The lipid levels were measured using an enzymatic assay with an automatic biochemical analyzer. The level of inflammation was detected by enzyme-linked-immunosorbent assay (ELISA). Autophagosomes were detected by transmission electron microscopy (TEM). Pyroptosis was detected by terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL)/caspase-1 and other proteins related to the expression levels of autophagy and pyroptosis were detected by Western blot analysis. Nucleotide oligomerization (NOD)-like receptor (NLR) family pyrin domain-containing protein 3 (NLRP3) inflammasome activation leads to pyroptosis, including the cleavage of caspase-1, interleukin (IL)-1β and IL-18 production, and the co-expression of TUNEL/caspase-1-all of these are inhibited by polydatin, whose inhibitory effect is similar to that of MCC950, a specific inhibitor of NLRP3. Further, polydatin decreased the protein expression of NLRP3 and the phosphorylated mammalian target of rapamycin (p-mTOR), and increased the number of autophagosomes as well as the increased the cytoplasmic microtubule-associated protein light chain 3 (LC3)/autophagosome membrane-type LC3 ratio. Moreover, the protein expression levels of p62 decreased, suggesting that polydatin can increase autophagy. Polydatin can inhibit the activation of the NLRP3 inflammasome and cleavage of caspase-1, thereby inhibiting pyroptosis and secretion of inflammatory cytokines, and promoting autophagy through NLRP3/mTOR pathway in AS.

Salvianolic acid B promotes the invasion and migration of HO-induced HTR-8/Svneo trophoblast cells by upregulating matrix metalloproteinase-9 the phosphatidylinositol-4,5-bisphosphate 3-kinase/protein kinase B pathway.

To elucidate the regulatory effects of salvianolic acid B (SalB) on trophoblast cells in preeclampsia (PE). 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenylte-trazolium bromide (MTT) assays were used to detect the viability of human extravillous trophoblast HTR-8/Svneo cells induced by HO following treatment with different concentrations of SalB. The levels of oxidative stress-related molecules, including superoxide dismutase, glutathione-Px and malondialdehyde were detected using corresponding kits. Cell apoptosis was detected using a Terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) assay, and the expression of apoptosis-related proteins was detected using western blot analysis. In the present study, wound healing and Transwell assays were performed to measure the levels of cell invasion and migration. Western blot analysis was also used to detect the expression levels of epithelial-mesenchymal transition-related proteins. The mechanisms underlying SalB were further investigated using reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) and western blot analysis, to determine the expression levels of matrix metallopeptidase 9 (MMP-9) and phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/protein kinase B (Akt). SalB increased the activity of HTR-8/Svneo cells, inhibited oxidative damage and promoted the invasion and migration of trophoblast cells induced by HO. Furthermore, the expression levels of MMP-9 and members of the PI3K/Akt signaling pathway were significantly decreased. The pathway agonist, LY294002, and MMP-9 inhibitor, GM6001, reversed the effects of SalB on HO-induced cells. SalB promoted the invasion and migration of HO-induced HTR-8/Svneo trophoblast cells by upregulating MMP-9 the PI3K/Akt signaling pathway.

Hepatocyte growth factor-mediated apoptosis mechanisms of cytotoxic CD8+ T cells in normal and cirrhotic livers

Intrahepatic stem/progenitor cells and cytotoxic CD8+ T cells (CD8+ T cells) in the cirrhotic liver undergo apoptosis, which potentially facilitates progression to cancer. Here, we report that hepatocyte growth factor (HGF) signaling plays an important role in promoting normal and damaged liver CD8+ T cell Fas-mediated apoptosis through its only receptor, c-Met. In addition to binding with HGF, c-Met also binds to Fas to form a complex. Using a diethylnitrosamine (DEN)-induced liver fibrosis/cirrhosis mouse model, immunostaining, and terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) staining, we found that HGF secretion was significantly higher at 10 weeks post-DEN, the liver cirrhotic phase (LCP), than at 3 weeks post-DEN, the liver fibrotic phase (LFP). Correspondingly, differences in CD8+ T cell proliferation and apoptosis were noted between the two phases. Interestingly, staining and TUNEL assays revealed lower smooth muscle actin (α-SMA)+ cell apoptosis, a marker for hepatic stellate cells (HSCs), in the LFP group than in the LCP group, which suggested a beneficial correlation among HGF, CD8+ T cells and HSCs in improving the fibrotic load during damaged liver repair. In cultures, when met different concentrations of recombinant HGF (rHGF), phytohemagglutinin (PHA)-stimulated naive mouse splenic CD8+ T cells (pn-msCD8+ T cells) responded differently; as increases in rHGF increased were associated with decreases in the clonal numbers of pn-msCD8+ T cells, and when the rHGF dose was greater than 200 ng/mL, the clonal numbers significantly decreased. In the presence of 400 ng/mL rHGF, the death-inducing signaling complex (DISC) can be directly activated in both nsCD8+ T cells and healthy human peripheral blood CD8+ T cells (hp-CD8+ T cells), as indicated by recruitment of FADD and caspase-8 because DISC forms via the recruitment of FADD and caspase-8, among others. These findings suggest that Fas-mediated apoptosis, may also indicate a regulatory role of HGF signaling in hepatic homeostasis.