MOLECULAR BIOLOGY
·
2024
·
IF 1.5
Yang S. J.,Ying J. L.,Xie W. J.
Abstract Microglia phagocytosis plays an important role in the pathogenesis of neurodegeneration. Defects or dysfunction of microglia phagocytosis were observed in neurodegenerative diseases, with different targets and associated receptors influencing the microglia response. Moreover, non-canonical LC3-associated (microtubule-associated protein 1 light chain 3) phagocytosis was extensively studied recently as a novel form of phagocytosis on macrophages, but little on microglia. Here, we investigated changes in phagocytic function of microglia activated by lipopolysaccharide (LPS) as well as rapamycin-regulated phagocytosis. Phagocytosis in mouse BV2 cells and primary microglia was analyzed by flow cytometry and immunofluorescence. Phagocytosis-related mechanisms in BV2 cells were analyzed using Western blotting and real-time polymerase chain reaction. Rapamycin was shown to reduce LPS-induced phagocytosis of microglia and at the same time stimulate LС3-dependent phagocytosis by regulating Atg3 , Atg4 and Atg7 expression. In addition, in BV2 cells, the PI3K/AKT/mTOR pathway may be involved in phagocytosis. These results suggest that phagocytosis of microglia is a complex process, and the increase in phagocytosis should not be considered as a maturation of phagocytic function. The data will provide new insights into the mechanisms of phagocytosis and neuroimmunity.
研究领域:
神经科学
·
免疫学
·
细胞生物学
·
药理学
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Ophthalmology
·
2021
·
IF 1.779
Qian Zhang,Hong-Song Li,Rong Li,Jun-Hui Du,Cong Jiao
AIM To observe the role and mechanism of autophagy in retinal pigment epithelial cell (RPE) damaged by high glucose, so as to offer a new idea for the treatment of diabetic retinopathy (DR). METHODS ARPE-19, a human RPE cell line cultured in vitro was divided into the normal control (NC), autophagy inhibitor 3-methyladenine (3-MA), high-glucose (HG), and HG+3-MA groups. Cell viability was detected by CCK-8 assay and the apoptosis rate was measured by flow cytometry. The protein expressions of apoptosis markers, including Bax, Bcl-2, and Caspase-3, as well as autophagy marker including microtubule-related protein 1 light chain 3 (LC3), p62, and mechanistic target of rapamycin (mTOR) were detected by Western blotting. Autophagic flux was detected by transfection with Ad-mCherry-GFP-LC3B. RESULTS Under high glucose conditions, the viability of ARPE-19 was decreased, and the apoptosis rate increased, the protein expressions of Bax, Caspase-3, and LC3-II/LC3-I were all increased and the expressions of Bcl-2, p62 and p-mTOR decreased, and autophagic flux was increased compared with that of the controls. Treatment with 3-MA reversed all these changes caused by high glucose. CONCLUSION The current study demonstrates the mechanisms of cell damage of ARPE-19 through high glucose/mTOR/autophagy/apoptosis pathway, and new strategies for DR may be developed based on autophagy regulation to manage cell death of RPE cells.
研究领域:
眼科学
·
细胞生物学
·
糖尿病
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOMEDICINE & PHARMACOTHERAPY
·
2018
·
IF 3.457
Jian Yin,Ge Gong,Chao Sun,Zhaoyang Yin,Chao Zhu,Bin Wang,Qin Hu,Yuerong Zhu,Xinhui Liu
Angiogenesis plays a key role in the repair of large segmental bone defects with tissue-engineered bones. However, there is no effective method of promoting angiogenesis in tissue-engineered bone. Both angiopoietin 2 (Ang2) and autophagy have been shown to be involved in angiogenesis, but their roles in angiogenesis of tissue-engineered bone remains unknown. In this in vivo study, a radius bone defect was created in New Zealand white rabbits, which were then treated by implantation of a hydroxyapatite/collagen scaffold followed by injection of different concentrations of Ang2. Expression of the autophagic modulators microtubule-associated protein 1 light chain 3 (LC3), Beclin-1, and SQSTM1/P62 were measured via western blotting, while the angiogenic modulators VEGF and CD31 were detected by western blotting and immunohistochemistry, respectively. X-ray imaging combined with general observation was used to evaluate bone defect healing. Expression of LC3 -I/LC3-II, Beclin-1, VEGF, and CD31 in the callus area increased and SQSTM1/p62 decreased in a dose-dependent manner with increasing Ang2 concentration. In the group treated with a high concentration of Ang2, the new callus grew well, accompanied by remarkable angiogenesis, leading to good repair of the bone defects. However, in the low concentration of Ang2 group, in spite of the existence of angiogenesis and new bone formation, the bone defects were not repaired. Furthermore, angiogenesis and osteogenesis were both obstructed in the control group. In conclusion, our study demonstrated that a high concentration of Ang2 promoted angiogenesis in tissue-engineered bone and improved repair of bone defects by inducing autophagy.
研究领域:
生物医学工程
·
组织工程
·
骨科
·
分子生物学
✓ 已验证
DOI
PubMed
高影响因子
Frontiers in Pharmacology
·
2021
·
IF 5.811
Tong Yuling,Liu Liping,Wang Ruilin,Yang Tao,Wen Jianxia,Wei Shizhang,Jing Manyi,Zou Wenjun,Zhao Yanling
The purpose of this study was to investigate the therapeutic effect of berberine (BBR) on MNNG-induced chronic atrophic gastritis (CAG) and the possible mechanism of BBR through TGF-β1/PI3K signal pathway. GES-1 were pretreated with MNNG for 2 h before BBR treatment in all procedures. Cell viability was quantified by cell counting kit-8, and GES-1 morphology and proliferation were detected by high content screening (HCS) assay. The rat model of CAG was established by MNNG, and the therapeutic effect of BBR on stomach histopathology and serum supernatant were analyzed in vivo. In addition, the possible mechanism of BBR was further discussed, and the expression of related genes and proteins in TGF-β1/PI3K signal pathway was detected. The results showed that BBR could significantly improve the survival rate and morphological changes of GES-1, improve the gastric tissue injury of CAG rats, and reduce the expression of G-17 and inflammatory factors IL-8, TNF-α, IL-6 and IL-1β. In addition, BBR down-regulated the expression of TGF-β1 axis-related signals such as TGF-β1, PI3K, p-Akt/Akt, p-mTOR/mTOR and P70S6K, and promoted the expression of PTEN, LC3-II and Beclin-1. In Conclusion, BBR can improve CAG which may be closely related to TGF-β1/PI3K signal pathway.
研究领域:
药理学
·
胃肠病学
·
分子生物学
·
细胞生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ONCOLOGY REPORTS
·
2022
·Vol. 48
·期 6
·1-11
·
IF 4.136
Haoran Miao,Hongliang Hui,Huaming Li,Yangui Lin,Dan Li,Min Luo,Bo Jiang,Yiqian Zhang
Current investigations suggest that pigment epithelial‑derived factor (PEDF) can mediate the progression of non‑small cell lung cancer (NSCLC) by regulating autophagy. However, the underlying mechanisms associated with autophagy remain poorly elucidated. The aim of the present study was to investigate the association between the PEDF/adenosine 5'‑monophosphate‑activated protein kinase (AMPK)/Unc‑51 like autophagy‑activated kinase 1 (ULK1) pathway and autophagy in NSCLC. Intracellular autophagy was evaluated using indicators such as the expression and activation of microtubule‑associated protein light chain 3‑I (LC3‑I), LC3‑II and p62, as well as the distribution and number of autophagosomes observed by confocal microscopy. In addition, the activity and proliferative capacity of NSCLC cells under PEDF overexpression was also examined using Cell Counting Kit‑8 and lactate dehydrogenase (LDH) assays, and western blotting (WB) of related proteins. The results revealed that PEDF significantly inhibited NSCLC cell proliferation and viability, and increased LDH release and intercellular adhesion. Furthermore, PEDF suppressed the expression and activation of LC‑3 and reduced the number and distribution of autophagosomes. The PEDF‑induced inhibition of autophagy exhibited a direct association with the suppressed proliferation capacity and cell viability of NSCLC cells. The results of WB showed that NSCLC cells regulated autophagy through the AMPK/ULK1 signaling pathway. PEDF downregulated the AMPK/ULK1 signaling pathway, and AMPK or ULK1 overexpression markedly reduced the inhibitory effect of PEDF on autophagy. In conclusion, PEDF overexpression significantly inhibited the proliferative capacity and cell viability of NSCLC cells, as PEDF exerted an inhibitory function by regulating autophagy in NSCLC cells. Finally, it was demonstrated that autophagy may be suppressed by inhibiting the AMPK/ULK1 signaling pathway, thereby revealing a mechanism of lung cancer progression.
研究领域:
肿瘤学
·
分子生物学
·
细胞生物学
✓ 已验证
DOI
PubMed
高影响因子
Food & Function
·
2020
·Vol. 11
·期 5
·4193-4201
·
IF 4.171
Xianghe Meng,Chaosheng Xia,Qin Ye,Xiaohua Nie
tert-Butyl-p-benzoquinone (TBBQ), a metabolite of tert-butylhydroquinone from food, has cytotoxicity, the underlying mechanism of which is not clear. In this study, the viability of RAW 264.7 cells exposed to TBBQ at concentrations of 0.5–10 μg mL−1 was assayed by MTT. Results suggest that TBBQ decreased the viability in a dose-dependent manner. Monodansylcadaverine (MDC) staining results indicate the occurrence of autophagy induced by TBBQ, which was manifested by activation of LC3-II concurrent with the increased levels of Beclin1 and reduced levels of p62. Elevated lipid peroxide and decreased SOD activity by TBBQ exposure suggest the overproduction of ROS, which may account for the increase in the genotoxic stress protein p53. Both upregulation of p53 and reduction of Akt levels inhibited mTOR, which activated autophagy. Addition of 3-MA counteracted the impact of TBBQ on ATG proteins and cell viability. All of these results suggest that TBBQ induces autophagy of RAW 264.7 cells principally by inhibition of the Akt/mTOR signaling pathway, and they implicate ROS in this regulation.
研究领域:
药理学
·
细胞生物学
·
毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PHARMACEUTICAL BIOLOGY
·
2021
·
IF 3.503
Jiaqi Lu,Lili Gu,Qin Li,Ningzi Wu,Hongxing Li,Xinyue Zhang
Context Andrographolide (Andro) has a neuroprotective effect and a potential for treating Alzheimer’s disease (AD), but the mechanism has not been elucidated.Objective The efficacy of Andro on p62-mediated Kelch-like ECH-associated protein 1(Keap1)-Nuclear factor E2 related factor 2 (Nrf2) pathways in the aluminium maltolate (Al(mal)3)-induced neurotoxicity in PC12 cell was explored.Materials and methods PC12 cells were induced by Al(mal)3 (700 μM) to establish a neurotoxicity model. Following Andro (1.25, 2.5, 5, 10, 20, 40 μM) co-treatment with Al(Mal)3, cell viability was detected with MTT, protein expression levels of β-amyloid precursor protein (APP), β-site APP cleaving enzyme 1 (BACE1), Tau, Nrf2, Keap1, p62 and LC3 were measured via western blotting or immunofluorescence analyses. Nrf2, Keap1, p62 and LC3 mRNA, were detected by reverse transcription-quantitative PCR.Results Compared with the 700 μM Al(mal)3 group, Andro (5, 10 μM) significantly increased Al(mal)3-induced cell viability from 67.4% to 91.9% and 91.2%, respectively, and decreased the expression of APP, BACE1 and Keap1 proteins and the ratio of P-Tau to Tau (from 2.75- fold to 1.94- and 1.70-fold, 2.12-fold to 1.77- and 1.56-fold, 0.68-fold to 0.51- and 0.55-fold, 1.45-fold to 0.82- and 0.91-fold, respectively), increased the protein expression of Nrf2, p62 and the ratio of LC3-II/LC3-I (from 0.67-fold to 0.93- and 0.94-fold, 0.64-fold to 0.88- and 0.87-fold, 0.51-fold to 0.63- and 0.79-fold, respectively), as well as the mRNA expression of Nrf2, p62 and LC3 (from 0.48-fold to 0.92-fold, 0.49-fold to 0.92-fold, 0.25-fold to 0.38-fold). Furthermore, Nrf2 and p62 nuclear translocation were increased and keap1 in the cytoplasm was decreased in the presence of Andro. Silencing p62 or Nrf2 can significantly reduce the protein and mRNA expression of Nrf2 and p62 under co-treatment with Andro and Al(mal)3.Discussion and conclusions Our results suggested that Andro could be a promising therapeutic lead against Al-induced neurotoxicity by regulating p62-mediated keap1-Nrf2 pathways.
研究领域:
神经科学
·
药理学
·
细胞生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2019
·
IF 4.784
Qiang Chu,Shuang Zhang,Lushuang Yu,Yonglu Li,Yangyang Liu,Xiang Ye,Xiaodong Zheng
The tubers of Apios americana Medikus possess high nutritional value and have been used as food in many countries for a long time. However, few researches have focused on the tuber polysaccharides. In the present study, a purified polysaccharide (ATP-1) was isolated with the average molecular weights of 12.16 kDa. ATP-1 significantly suppressed the release of nitric oxide (NO) and inflammatory cytokines from LPS-induced RAW 264.7 cells, as well as oxidative stress and mitochondrial dysfunction. Meanwhile, ATP-1 reduced oxidative damage via the NF-κB, MAPKs and Nrf2-Keap1 signaling pathways in RAW264.7 macrophages. Furthermore, autophagy was activated by HMGB1-Beclin1, Sirt1-FoxO1 and Akt-mTOR signaling pathways, leading to a relief of oxidative stress, mitochondrial dysfunction, inflammation and an expression enhancement of autophagy-related proteins, such as LC3, Beclin1, Atg4, Atg5, and Atg7. In summary, our results suggested that ATP-1 might help to activate the anti-inflammation system，resulting in prevention of LPS-induced damage in RAW264.7 cells.
研究领域:
药理学
·
免疫学
·
细胞生物学
·
生物化学
✓ 已验证
DOI
PubMed
高影响因子
FOOD AND CHEMICAL TOXICOLOGY
·
2019
·
IF 3.775
Leying Jiang,Zhen Li,Yixi Xie,Liangliang Liu,Yi Cao
Recent studies suggest that phytochemicals , as part of the food matrix, might alter the toxicity of nanoparticles (NPs); however, relatively few studies have investigated the impact of anthocyanidins on the toxicity of NPs to cells lining the gastrointestinal tract. Therefore, this study used cyanidin chloride (CC) as the model for anthocyanidins and investigated the effects of CC on the toxicity of ZnO or Ag NPs to Caco-2 cells. Exposure to ZnO but not Ag NPs significantly induced cytotoxicity. The presence of CC, but not its analog quercetin (Qu), modestly protected Caco-2 cells from ZnO NP exposure. However, the intracellular superoxide, Zn ions , or release of interleukin-8 after ZnO NP exposure were not significantly affected by the presence of CC. Rather, CC promoted the expression of autophagic genes ATG5 , ATG7 , and BECN1 as well as the ratio of LC3-II/I after exposure to ZnO NPs. Meanwhile, the presence of autophagic inhibitors (chloroquine, NH 4 Cl, bafilomycin A1) significantly promoted the cytotoxicity of ZnO NPs and inhibited the cytoprotective effects of CC. In conclusion, these data suggest that CC could modestly protect Caco-2 cells from ZnO NP exposure, probably through the induction of autophagy.
研究领域:
毒理学
·
细胞生物学
·
药理学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACTA HISTOCHEMICA
·
2021
·
IF 2.479
Hongxi Wu,Guodong Li,Weiwei Chen,Wenbin Luo,Zhongyi Yang,Zhipeng You,Yuling Zou
Diabetic retinopathy (DR) is the leading clinical cause of blindness in diabetic patients. Mitophagy participates in the pathogenesis of DR. Dynamin related protein 1 (Drp1) is associated with mitophagy. Here, we investigated whether Drp1 can regulate mitophagy to affect the progression of DR. We constructed DR rat model by administration of streptozocin . Primary rat retinal endothelial cells (RECs) were treated with high glucose (HG) as a DR cell model. Drp1 was highly expressed in the retinal tissues of DR rats and HG-treated RECs. Drp1 knockdown inhibited HG-mediated increase of reactive oxygen species (ROS) levels and apoptosis in RECs. Moreover, Drp1 silencing inhibited the expression of autophagy-related proteins LC3-II/LC3–1 and Beclin-1 and reduced LC3 puncta in HG-treated RECs. The expression of mitochondrial marker Tom20 was reduced and the levels of mitophagy were increased in the HG-treated RECs, which was rescued by Drp1 silencing. Drp1 knockdown repressed LC3-II expression in HG-treated RECs, indicating that autophagy flux was inhibited. Rapamycin (autophagy activator) enhanced ROS levels and apoptosis in HG-treated RECs by activating autophagy, which was rescued by Drp1 knockdown. In conclusion, these data demonstrated that Drp1 knockdown repressed apoptosis of rat retinal endothelial cells by inhibiting mitophagy. Thus, this work suggests that targeted regulation of Drp1 may become a treatment for DR.
研究领域:
眼科学
·
细胞生物学
·
分子生物学
·
糖尿病
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nature Communications
·
2022
·Vol. 13
·期 1
·1-22
·
IF 17.694
Zhou Tian,Li Yuxin,Li Xiaoyu,Zeng Fanzhuo,Rao Yanxia,He Yang,Wang Yafei,Liu Meizhen,Li Dali,Xu Zhen,Zhou Xin,Du Siling,Niu Fugui,Peng Jiyun,Mei Xifan,Ji Sheng-Jian,Shu Yousheng,Lu Wei,Guo Feifan,Wu Tianzhun,Yuan Ti-Fei,Mao Ying,Peng Bo
Microglia are important immune cells in the central nervous system (CNS) that undergo turnover throughout the lifespan. If microglial debris is not removed in a timely manner, accumulated debris may influence CNS function. Clearance of microglial debris is crucial for CNS homeostasis. However, underlying mechanisms remain obscure. We here investigate how dead microglia are removed. We find that although microglia can phagocytose microglial debris in vitro, the territory-dependent competition hinders the microglia-to-microglial debris engulfment in vivo. In contrast, microglial debris is mainly phagocytosed by astrocytes in the brain, facilitated by C4b opsonization. The engulfed microglial fragments are then degraded in astrocytes via RUBICON-dependent LC3-associated phagocytosis (LAP), a form of noncanonical autophagy. Interference with C4b-mediated engulfment and subsequent LAP disrupt the removal and degradation of microglial debris, respectively. Together, we elucidate the cellular and molecular mechanisms of microglial debris removal in mice, extending the knowledge on the maintenance of CNS homeostasis.
研究领域:
神经科学
·
免疫学
·
细胞生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2025
·
IF 6.1
Yanzi Zhao,Yujing Niu,Xuefei Wang,Peng Wan,Zhanfei Ma,Jian Sun,Shoufang Jiang,Ling Xue,Nan Liu
Indium-tin oxide nanoparticles (Nano-ITO) are widely used in various applications as infrared shielding materials, which increase the risk of occupational exposure. According to reports, Nano-ITO can cause indium lung disease in occupational exposed workers, but the specific mechanism of Nano-ITO-induced pulmonary toxicity remains unclear. In this study, 50 8-week-old male Sprague-Dawley rats were divided into five groups (10 rats in each group) as follows: control group (physiological saline), 1.2 mg/kg Nano-ITO group, 6 mg/kg Nano-ITO group, N-Acetyl-L-Cysteine (NAC) control group (200 mg/kg), and NAC + Nano-ITO group (200 mg/kg NAC intraperitoneal injection, after 1.5 h, 6 mg/kg Nano-ITO intratracheal instillation), twice a week for 12 weeks. Pathological and ultrastructural changes in the rat lung tissue, immunofluorescence assays, immunohistochemistry, protein and mRNA levels of apoptosis- and autophagy-related genes were measured. The levels of ROS, MDA, H 2 O 2 , and LDH, and the activities of T-AOC and SOD, were determined using oxidative stress assay kits. The results showed that Nano-ITO caused strong pulmonary inflammation, pulmonary alveolar proteinosis, and pulmonary interstitial fibrosis. In addition, Nano-ITO-induced oxidative stress in rat lungs presented as increased levels of ROS and H 2 O 2 in the lungs, increased LDH and MDA levels, SOD and T-AOC activity in BALF, and activation of the Nrf2/NQO1/HO-1 signaling pathway. Intriguingly, Nano-ITO significantly increased the protein expression of microtubule-associated protein light chain 3 (LC3-II), the protein levels of autophagy-related genes 5 (ATG5), and Beclin-1 (BECN1), and reduced the protein levels of phosphatidylinositol 3-kinase (PI3K) in lung tissues. In addition, transmission electron microscopy (TEM) showed a significant increase in autophagic vesicles in the cytoplasm of lungs treated with Nano-ITO, indicating that Nano-ITO induces autophagy in rat lungs. Moreover, apoptosis also participates in Nano-ITO-induced pulmonary injury in a synchronous manner, as evidenced by the enhancement of TUNEL-positive signals and activation of the apoptosis pathway (Bax and Bcl-2 positive proportions). NAC supplementation restored most of the pathological structural features of rat lung tissue to their physiological range and effectively weakened apoptosis, as demonstrated by the notable reductions in TUNEL, Bax, and Bcl-2 protein expression levels in the lungs. Although autophagy was detected in the lungs of rats in the Nano-ITO and NAC + Nano-ITO groups, we discovered that NAC could rescue the expression of ATG5 and BECN1 induced by Nano-ITO, thus indicating that exposure to Nano-ITO promotes pulmonary apoptosis and autophagy by mediating oxidative stress. These results indicate that Nano-ITO can cause pulmonary injury by inducing oxidative stress, which activates apoptosis and autophagy, ultimately leading to alveolar proteinosis and interstitial fibrosis.
研究领域:
毒理学
·
纳米技术
·
呼吸医学
·
分子生物学
·
药理学
·
病理学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）