Objective To review the mechanism and effects of cell autophagy in the pathophysiology changes of peripheral nerve injury. Methods The recent literature about cell autophagy in peripheral nerve injury and regeneration was extensively reviewed and summarized. Results The researches through drugs intervention and gene knockout techniques have confirmed that the Schwann cell autophagy influences the myelin degeneration, debris clearance, inflammatory cells infiltration, and axon regeneration through JNK/c-Jun pathway. To adjust autophagy process could slow down the Wallerian degeneration, maintain the integrity of injured nerve, while the effect on axon regeneration is still controversial. Conclusion The Schwann cell autophagy plays a key role in the pathophysiology changes of peripheral nerve injury, the further study of its mechanism could provide new methods for the therapy of peripheral nerve injury.
Objective To investigate the effect of epigallocatechin gallate (EGCG) on chondrocyte senescence and its mechanism. Methods The chondrocytes were isolated from the articular cartilage of 4-week-old Sprague Dawley rats, and cultured with type Ⅱcollagenase and passaged. The cells were identified by toluidine blue staining, alcian blue staining, and immunocytochemical staining for type Ⅱ collagen. The second passage (P2) cells were divided into blank control group, 10 ng/mL IL-1β group, and 6.25, 12.5, 25.0, 50.0, 100.0, and 200.0 μmol/L EGCG+10 ng/mL IL-1β group. The chondrocyte activity was measured with cell counting kit 8 after 24 hours of corresponding culture, and the optimal drug concentration of EGCG was selected for the subsequent experiment. The P2 chondrocytes were further divided into blank control group (group A), 10 ng/mL IL-1β group (group B), EGCG+10 ng/mL IL-1β group (group C), and EGCG+10 ng/mL IL-1β+5 mmol/L 3-methyladenine (3-MA) group (group D). After cultured, the degree of cell senescence was detected by β-galactosidase staining, the autophagy by monodansylcadaverine method, and the expression levels of chondrocyte-related genes [type Ⅱ collagen, matrix metalloproteinase 3 (MMP-3), MMP-13] by real-time fluorescent quantitative PCR, the expression levels of chondrocyte-related proteins (Beclin-1, LC3, MMP-3, MMP-13, type Ⅱ collagen, P16, mTOR, AKT) by Western blot. Results The cultured cells were identified as chondrocytes. Compared with the blank control group, the cell activity of 10 ng/mL IL-1β group significantly decreased (P<0.05). Compared with the 10 ng/mL IL-1β group, the cell activity of EGCG+10 ng/mL IL-1β groups increased, and the 50.0, 100.0, and 200.0 μmol/L EGCG significantly promoted the activity of chondrocytes (P<0.05). The 100.0 μmol/L EGCG was selected for subsequent experiments. Compared with group A, the cells in group B showed senescence changes. Compared with group B, the senescence rate of chondrocytes in group C decreased, autophagy increased, the relative expression of type Ⅱ collagen mRNA increased, and relative expressions of MMP-3 and MMP-13 mRNAs decreased; the relative expressions of Beclin-1, LC3, and type Ⅱ collagen proteins increased, but the relative expressions of P16, MMP-3, MMP-13, mTOR, and AKT proteins decreased; the above differences were significant (P<0.05). Compared with group C, when 3-MA was added in group D, the senescence rate of chondrocytes increased, autophagy decreased, and the relative expressions of the target proteins and mRNAs showed an opposite trend (P<0.05). ConclusionEGCG regulates the autophagy of chondrocytes through the PI3K/AKT/mTOR signaling pathway and exerts anti-senescence effects.
Atherosclerotic cardiovascular disease (ASCVD) is a disease caused by the accumulation of atherosclerotic plaques that leads to arterial hardening and impairment of contractility. Proprotein convertase subtilisin/kexin type 9 (PCSK9) can increase low-density lipoprotein cholesterol levels in plasma, which accelerates the development and progression of ASCVD. This article intends to review the biological characteristics and functional mechanisms of PCSK9, elucidate its impact on the development and progression of ASCVD, provide research literature support for the diagnosis and treatment of such diseases and improving the prognosis of patients.
Neonatal broncho-pulmonary dysplasia (BPD) is a common chronic lung disease in premature infants, with a complex pathogenesis and limited treatment options, severely affecting health. In recent years, targeted autophagy and mesenchymal stem cell (MSC) have received attention as potential therapeutic approaches. Autophagy is crucial in the development of BPD, as it can improve pathological processes such as alveolarization disorders, abnormal pulmonary vascular development, and inflammatory responses through targeted regulation, and enhance the pulmonary microenvironment. Meanwhile, MSC is considered to have promising applications in promoting lung development and repair due to immune regulatory properties and paracrine functions. This article reviews the mechanisms and synergistic effects of targeted autophagy and MSC therapy for BPD, providing a theoretical basis for optimizing clinical treatment strategies for BPD and improving the quality of life of premature infants.
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.
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.
Neuropathic pain (NP) is a pathological state caused by damage or disease to the somatosensory nervous system. Programmed cell death (PCD) is an orderly process of cell death regulated by both intrinsic signals and external stimuli. In recent years, an increasing number of studies have shown that PCD plays a key regulatory role in the pathogenesis of NP. This article reviews the molecular mechanisms of various types of PCD and their specific roles in NP, in order to provide new research directions for the prevention, diagnosis, and treatment of NP.
ObjectiveTo summarize the mechanism of hydrogen sulfide (H2S) in regulating autophagy and ameliorating multi-organ dysfunction in the treatment of sepsis.MethodThe relevant literatures at home and abroad in recent years were systematically searched and read to review the mechanism of H2S in regulating autophagy and ameliorating multi-organ dysfunction during sepsis.ResultsAs a new medical gas signal molecule, H2S could regulate autophagy by regulating multiple signal pathways such as Nrf2, NF-κB, MAPK, AMPK, etc., then ameliorated multi-organ dysfunction in sepsis.ConclusionH2S inhibits inflammation, oxidative stress, and apoptosis by regulating autophagy, thus ameliorating multi-organ dysfunction in sepsis, which is expected to become an effective therapeutic target for sepsis.
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.