ObjectiveTo analyze the expression and significance of NF-κBp65 and autophagy-related proteins Beclin1 and p62 in patients with papillary thyroid carcinoma (PTC).MethodsOne hundred and sixty cases of PTC patients' tumor tissue specimens and paracancerous tissue specimens in our hospital from March 2013 to February 2015 were collected, and 90 cases of cervical lymph node metastasis tissue specimens of the above patients were collected. The expressions of NF-κBp65, Beclin1 and p62 in PTC tissues, metastatic lymph node tissues and paracancerous tissues were detected by immunohistochemical method, and the relationship between the above indexes and the clinicopathological characteristics and prognosis of PTC patients was analyzed.ResultsThe positive rates of expression of NF-kappa Bp65 and p62 in PTC tissues and metastatic lymph node tissues were higher than those in paracancerous tissues (P<0.05). The expression rate of Beclin1 in PTC tissues and metastatic lymph node tissues was lower than that in paracancerous tissues (P<0.05). The positive rate of NF-κBp65 expression in PTC tissues was not related to the clinicopathological characteristics of patients (P>0.05). The expression of p62 decreased with the increase of tumor differentiation (P<0.05). The expression of Beclin1 in patients with stage Ⅲ+Ⅳ and lymph node metastasis were lower than those in patients with stage Ⅰ+Ⅱ and without lymph node metastasis (P<0.05), while the expression of p62 was opposite. Spearman correlation analysis showed that the expression of Beclin1 and p62 in PTC tissues was negatively correlated (r=–0.656, P<0.01). In metastatic lymph node tissues, the expression of Beclin1 and p62 was also negatively correlated (r=–0.562, P<0.01). The 3-year survival rates of patients with positive expression of p62 and NF-κBp65 in PTC tissues were lower than that of patients with negative expression (P<0.05). The 3-year survival rate of patients with positive expression of Becrin1 was higher than that of negative expression (P<0.05). TNM stage, lymph node metastasis, NF-κBp65 and p62 were independent risk factors for PTC prognosis, and Beclin1 was protective factor.ConclusionsNF-κBp65 and p62 are highly expressed in PTC tissues and lymph node metastasis tissues, while Beclin1 is poorly expressed, which could be used as independent prognostic factors for PTC patients. In addition, Beclin1 and p62 are related to PTC biological behavior and may become potential indicators for PTC diagnosis.
ObjectiveTo explore the effects of PKD1 gene on mouse aortic smooth muscle (MOVAS) cells autophagy.MethodsThe shRNA and over-expression lentiviral vectors for the target gene of PKD1 were constructed. MOVAS cells were infected by a number of successful packaging shRNA (PKD1 knockdown) or ETS-1 (PKD1 over-expressing) lentiviral vectors, and qPCR was used to test interference and over-expressing effects. Then qPCR and Western blotting were used to detect the expression levels of autophagy markers including Atg5, Beclin1 and LC3 in control group, shPKD1 group and ETS-1 group.ResultsCompared with the control group, PKD1 mRNA level was decreased in the shPKD1 group (P<0.05); ETS-1 and PKD1 mRNA levels were increased in the ETS-1 group (P<0.05). In contrast with the control group, the mRNA levels of autophagy markers including Atg5 (P<0.05) and Beclin1 (P<0.01) were obviously decreased in the shPKD1 group, but they were obviously increased in the ETS-1 group (P<0.001). Protein levels of Atg5, Beclin1 and LC3 were significantly decreased in the shPKD1 group (P<0.05), but they were increased obviously in the ETS-1 group (P<0.05) in contrast with the control group.ConclusionPKD1 gene is involved in MOVAS cells autophagy, low expression of PKD1 gene can inhibit autophagy and high expression of PKD1 promotes autophagy in vascular smooth muscle cells.
Objective To investigate the changes of autophagy after spinal cord injury (SCI) in rats and its relationship with multisite phosphorylation of B-cell lymphoma-2 (Bcl-2) protein. Methods Forty male Sprague-Dawley rats aged 8 weeks were used to prepare SCI models by modified Allen method, and the SCI model were prepared successfully in 36 rats. The 36 SCI models were randomly divided into SCI group, autophagy inhibitor group, and autophagy promoter group, with 12 rats in each group. Another 12 rats were selected as sham operation group with only laminectomy and no spinal cord injury. At the end of modeling, the autophagy inhibitor group and the autophagy promoter group were intrathecally injected with 20 μL of 600 nmol/L 3-methyladenine and 25 nmol/L rapamycin, respectively, once a day for 4 weeks. The sham operation group and the SCI group were injected with only 20 μL of normal saline at the same time point. The motor function of rat in each group was evaluated by the Basso-Beattie-Bresnahan (BBB) score at 1 day and 1, 2, 4 weeks after modeling. The rats in each group were sacrificed at 24 hours after the last injection and the spinal cord tissues were taken. ELISA assay was used to detect the levels of inflammatory factors in spinal cord tissues, including myeloperoxidase (MPO), tumor necrosis factor α (TNF-α), and interleukin 1β (IL-1β); the morphological changes of spinal cord were observed by HE staining; the autophagy of mitochondria in spinal cord tissues was observed by transmission electron microscopy; the expressions of Beclin1 and microtubule-associated protein light chain 3 (LC3) were detected by immunofluorescence staining; neuronal apoptosis in spinal cord tissues were observed by TUNEL staining; LC3/TUNEL positive cells were calculated by immunofluorescence double staining; the expressions of Bcl-2 associated X protein (Bax), Bcl-2, p-Bcl-2 (Ser87), and p-Bcl-2 (Ser70) were detected by Western blot. Results Compared with sham operation group, BBB score of SCI group decreased at each time point, while the levels of MPO, TNF-α, and IL-1β increased; peripheral space of nerve cells enlarged, cells swelled, vacuoles appeared, and autophagic bodies appeared in mitochondria; the positive rates of Beclin1 and LC3 proteins, and apoptotic rate of neurons significantly increased; the LC3/TUNEL positive cells significantly increased; the expressions of Bax, p-Bcl-2 (Ser87), and p-Bcl-2 (Ser70) proteins increased, while the expression of Bcl-2 protein decreased; all showing significant differences (P<0.05). Compared with SCI group, BBB score in autophagy inhibitor group decreased at each time point, while the levels of MPO, TNF-α, and IL-1β increased; a few autophagic vesicles appeared in mitochondria; the positive rates of Beclin1 and LC3 proteins decreased and the apoptotic rate of neurons increased significantly; the LC3 positive cells decreased and the TUNEL positive cells increased; the expressions of Bax, p-Bcl-2 (Ser87), and p-Bcl-2 (Ser70) proteins increased, while the expression of Bcl-2 protein decreased. The results of autophagy promoter group were opposite to those of autophagy inhibitor group; all showing significant differences between groups (P<0.05). Conclusion Induction of autophagy after SCI in rats can reduce neuronal apoptosis and protect spinal cord function, which may be related to the inhibition of Bcl-2 protein multisite phosphorylation.
Cell autophagy plays a key role in maintaining intracellular nutritional homeostasis during starvation through elimination of aberrant or obsolete cellular structures. The cellular cytoskeleton has a crucial role in multiple processes involving membrane rearrangements and vesicle-mediated events. Autophagy is mediated by both microtubules and actin networks: microtubules promote the synthesis of autophagosome and are related to the movement of autophagosome; actin networks have been implicated in structurally supporting the expanding of phagophore, moving autophagosomes and enabling their efficient fusion with the lysosome; non-muscle myosinⅡoperates in the early stages of autophagy during the initiation and expansion of the phagophore, whereas myosinⅥ and myosin 1C are involved in the late stages of autophagosome maturation and fusion with the lysosome, respectively. This review summarizes the multiple regulation of cytoskeleton on autophagy and focuses on the regulation of autophagy by actin and myosin, providing a new approach for the study of pathogenesis and innovative therapies of autophagy related diseases.
Nuclear receptors are transcriptional regulators involved in almost all biological processes such as cell growth, differentiation, apoptosis, substance metabolism and tumor formation, and they can be regulated by small molecules that bind to them. Autophagy is a special way of programmed cell death and it is a highly conserved metabolic process. Once autophagy defects or excessive autophagy occur, the disease will develop. In recent years, numerous studies have shown that nuclear receptors are related to autophagy. Therefore, this paper mainly reviews the research progress on nuclear receptors involved in the regulation of autophagy, and focuses on the mechanism of several nuclear receptors involved in the regulation of autophagy, aiming at understanding the molecular basis of how nuclear receptors participate in regulating autophagy, as well as providing possible ideas and strategies for the treatment of corresponding diseases.
Hypoxia inducible factor-1 (HIF-1) is the main transcription factor and the core regulator for cells to adapt to hypoxia, and oxygen homeostasis is achieved by controlling and utilizing oxygen delivery. Autophagy and apoptosis play an important role in determining cell fate and maintaining cell homeostasis. In recent years, it has been found that the dynamic change of HIF-1 expression plays a key role in the hypoxic adaptive response of cardiomyocytes. The regulation of HIF-1 on autophagy and apoptosis of hypoxic cardiomyocytes determines the survival of cardiomyocytes, which is of great significance for the prognosis of ischemic heart disease.
ObjectiveTo summarize the recent advances in the relationship between long non-coding RNA (LncRNA) and tumor autophagy, autophagy and drug resistance regulation.MethodsReviewed the relevant literatures at home and abroad, and reviewed the recent research progress of LncRNA regulation of autophagy to affect tumor resistance.ResultsDrug resistance was a common problem in the process of anti-tumor therapy. Autophagy played an important role in the process of tumor resistance as an important mechanism to maintain cell homeostasis. Abnormal regulation of LncRNA could contribute to the occurrence and development of tumors, and could also mediate the resistance of tumor cells to anti-tumor drugs by promoting or inhibiting autophagy.ConclusionsLncRNA can mediate tumor autophagy in a positive or negative direction, and autophagy is a " double-edged sword” for tumor resistance. LncRNA may improve tumor resistance to drugs by regulating autophagy.
Objective To investigate the role of mitochondrial autophagy mediated by PINK1 (homologous phosphatase tensin induced kinase 1) /Parkin (Parkinson’s protein) signaling pathway in severe pneumonia of rats. Methods Twenty rats were randomly divided into control group and model group (severe pneumonia model), with 10 rats in each group, to explore the effects of severe pneumonia on lung function and pathology in rats. Then, 30 rats were randomly divided into control group, model group and mdivi-1 (mitochondrial autophagy inhibitor) group, with 10 rats in each group, to further explore the effects of severe pneumonia on mitochondrial autophagy indicators of rats. ResultsCompared with the control group, the resting ventilation volume [(3.44±0.22) vs. (1.58±0.18) mL/min] and airway resistance ratio (77.48±3.84 vs. 47.76±5.54) in the model group were decreased (P<0.05). In the model group, the lung tissue was injured and a large number of inflammatory cells were infiltrated. The protein and mRNA expression levels of Parkin, PINK1 and microtubule-associated protein1 light chain 3 in lung tissues of model group were increased (P<0.05). Compared with model group, the ratio of resting ventilator-to-airway resistance in mdivi-1 group increased (P<0.05). The injury and inflammatory infiltration of lung tissue were improved in mdivi-1 group. The expression levels of Parkin, PINK1 and microtubule-associated protein1 light chain 3 protein and mRNA in lung tissues of mdivi-1 group were decreased (P<0.05). Conclusion Mdivi-1 can improve the abnormal lung function structure in rats with severe pneumonia, and the mechanism may be related to mitochondrial autophagy mediated by PINK1/Parkin signaling pathway.
Objective To analyze the hotspots and development trends in the research field of tumor cell apoptosis and autophagy. Methods Relevant literature on tumor apoptosis and autophagy published between January 2012 and December 2021 were searched through the Web of Science core collection database, and CiteSpace 5.8.R3 software and VOSviewer version 1.6.10 software were used to analyze the country/region, institution, keywords and citation node information of the literature. Results A total of 6716 foreign-language articles were included in the study after searching and screening, and the number of papers showed a linear upward trend year by year. China published the largest number of articles and cooperated closely with other research institutions, but there were not many high-quality and influential articles. The two journals Autophagy and Cell were more authoritative in the field of tumor apoptosis and autophagy research. The signaling pathways and related proteins of apoptosis and autophagy, and the study of tumor suppressor mechanisms based on apoptosis/autophagy were current research hot topics. The migration, apoptosis and epithelial mesenchymal transformation of cancer cells would be the research focus and direction in the future. Conclusions In the past 10 years, the research on tumor apoptosis and autophagy has continued to develop. With the in-depth research on the molecular level, the study of its mechanism is expected to further reveal the mystery of tumor apoptosis and autophagy.
ObjectiveTo investigate the role of p22phox and NOX5 in autophagy and apoptosis of osteoblasts induced by hypoxia.MethodsThe skull tissue of newborn rats was cut into small pieces, and the osteoblasts were separated and purified by the tissue block adherent method and the differential adherent method. The first generation cells were harvested and identified by HE staining, Alizarin red staining, alkaline phosphatase (ALP) staining, and flow cytometry. A three-gas incubator was used to prepare a hypoxia model of osteoblasts. At 0, 3, 6, 12, and 24 hours of hypoxia, the expressions of p22phox, NOX5, and LC3Ⅱ/Ⅰ were detected by Western blot, and the level of reactive oxygen species (ROS) and cell apoptosis rate were detected by flow cytometry. And the time point of the highest level of ROS was selected as the hypoxia time point for subsequent experiments. The first generation osteoblasts were divided into normal group, si-p22phox hypoxia group, and si-NOX5 hypoxia group and subjected to corresponding transfection and hypoxia treatment. The inhibition efficiency of si-p22phox and si-NOX5 were detected by RT-PCR. Then the osteoblasts were divided into normal group, si-NC hypoxia group, si-p22phox hypoxia group, and si-NOX5 hypoxia group. After transfection and hypoxia treatment, Western blot was used to detect the expressions of p22phox, NOX5, autophagy-related proteins (LC3Ⅱ/Ⅰ, Beclin), and apoptosis-related proteins (Bcl-2, Bax), and flow cytometry was used to detect the cell apoptosis rate and level of ROS. The first generation osteoblasts were divided into a hypoxia group for 12 hours (hypoxia group) and a group that simultaneously inhibited si-p22phox and si-NOX5 and hypoxia for 12 hours (inhibition+hypoxia group). The expressions of Beclin and Bax were observed by immunofluorescence staining after the corresponding treatment.ResultsAfter identification, the isolated cells were osteoblasts. After hypoxia treatment, the relative expressions of p22phox, NOX5, and LC3Ⅱ/Ⅰ proteins and the apoptosis rate of osteoblasts gradually increased (P<0.05), and the level of ROS also significantly increased (P<0.05) and reached the peak value at 12 hours. The 12-hour hypoxia model was selected for subsequent experiments. Silencing the p22phox gene did not affect the expression of NOX5, and silencing the NOX5 gene did not affect the expression of p22phox. Compared with hypoxia treatment, the relative expressions of LC3Ⅱ/Ⅰ, Beclin, and Bax proteins after inhibiting the expression of p22phox or NOX5 gene significantly decreased (P<0.05), the relative expression of Bcl-2 protein significantly increased (P<0.05), the cell apoptosis rate and level of ROS also significantly decreased (P<0.05). After silencing the expressions of p22phox and NOX5 genes at the same time, the immunofluorescence staining showed that the fluorescence of Beclin and Bax were weak.ConclusionInhibiting the expressions of p22phox and NOX5 genes can reduce the level of ROS in osteoblasts under hypoxia-induced conditions, and at the same time reduce autophagy and apoptosis, especially attenuate the excessive apoptosis of cells in the early to late stages, and strengthen the hypoxic osteoblasts proliferation.