Age-related macular degeneration is one of the major causes of blindness in the elderly. As an important pathway of cell metabolism, autophagy maintains intracellular homeostasis through the degradation and recycle of damaged organelles and macromolecules. Understanding its mechanism may promote discoveries to delay aging process, reduce the incidence of age-related diseases. In mammals, silent information regulator protein 6 (SIRT6) plays its deacetylase and ribonucleotransferase activity in multiple signaling pathways, including inhibition of cellular senescence, tumorigenesis, metabolic diseases, regulating cellular lifespan. It has a significant impact on the structure and function of tissues and organs. SIRT6 regulates intracellular autophagy mainly through the insulin-like growth factor-protein kinase B-mammalian target of rapamycin, reducing the accumulation of toxic metabolites and cellular senescence. The function of SIRT6 in age-related macular degeneration need to be combined with the genetic background, pathogenesis, clinical manifestations and other aspects of the disease, and it is expected to be further studied in subsequent studies.
ObjectiveTo investigate the expression of autophagy-related genes and proteins in the lung tissues of patients with non-small cell lung cancer (NSCLC).MethodsPulmonary tissues were obtained from the surgically resected lung tissues of patients with NSCLC who were clinical diagnosed. The lung cancer tissues were derived from the pathologically diagnosed NSCLC and the normal tissues were from lung tissues 5 cm away from the lung lesions (29 cases in the lung cancer group and 32 cases in the normal group). The expression of autophagy-related proteins ATG5, LC3B, and p62 in lung tissues were measured by Western blot, and mRNA expression of ATG5 and p62 in the lung tissues were measured by real-time PCR.ResultsWestern blot analysis showed that the expression of ATG5 and p62 in lung cancer group were significantly higher than those in normal group (P<0.05). However, the expression of LC3B in lung cancer group was significantly lower than that in normal group (P<0.05). Real-time PCR analysis found that the mRNA expression of ATG5 and p62 in lung cancer group were significantly higher than those in normal group (P<0.05). The expression of ATG5, LC3B and p62 had no relationship with gender, age, smoking history, tumor location, tumor size, clinicopathological classification, differentiation or TNM stage. The expression of ATG5 had statistical significance in lymph node metastasis (P<0.05), but there was no difference for LC3B or p62 in lymph node metastasis (P>0.05).ConclusionsAutophagy plays a role in the tumorigenesis of lung cancer. If it’s possible to regulate and control autophagy-related genes and proteins effectively, it may supply new insights or targets into treatment for lung cancer patients.
ObjectiveTo investigate the changes of autophage-related protein in lung tissues of rats with chronic obstructive pulmonary disease (COPD).
MethodsPassive cigarette smoking was used to establish COPD model in rats. The mRNA and protein expressions of PI3K, total AKT, phosphorylated-AKT, total mTOR, phosphorylated-mTOR, and autophagy-related genes including LC3Ⅱ/Ⅰ, Beclin1, Atg5, Atg7, Atg12, P62 in lung tissues were measured by real-time PCR and Western blot. The autophagy level was compared between the COPD rats and the normal rats by LC3B immunohistochemistry.
ResultsReal-time PCR analysis showed that the mRNA expressions of Beclin1, Atg5 and Atg12 significantly increased in lung tissues of the COPD rats compared with the normal rats (all P < 05). There was no significant difference between the COPD rats and the normal rats as for Atg7 mRNA expression (P > 0.05). Western blot analysis showed that the protein expressions of PI3K, p-AKT/AKT and p-mTOR/mTOR significantly decreased, the protein expressions of LC3 Ⅱ/Ⅰ, Atg5, and Beclin1 increased, and protein expression of P62 significantly decreased in lung tissues of the COPD rats compared with the normal rats (all P < 05). LC3B immunohistochemistry showed that the LC3B expression was higher in the COPD rats than that in the normal rats.
ConclusionThe level of autophagy significantly increases in COPD rats with decreased expression of upstream proteins in autophagy signal pathway and increased expression of autophage proteins.
Age-related macular degeneration (AMD) is one of the leading causes of vision impairment and blindness in the elderly worldwide, with its prevalence increasing significantly with age. The pathogenesis of AMD is multifactorial, involving genetic predisposition, environmental risk factors, chronic inflammation, and mitochondrial dysfunction. In recent years, mitophagy has emerged as a critical mechanism for maintaining mitochondrial quality control, energy homeostasis, and cellular integrity in retinal pigment epithelium (RPE) and photoreceptor cells. Dysregulated mitophagy leads to the accumulation of damaged mitochondria, excessive reactive oxygen species, and metabolic imbalance, thereby triggering RPE dysfunction, inflammatory amplification, and choroidal neovascularization, which drive AMD progression. Both classical pathways (e.g., PINK1/Parkin) and non-classical pathways (e.g., BNIP3, FUNDC1) have been implicated in AMD pathophysiology. Molecules such as Parkin and p62, as well as multimodal imaging features, hold promise as early biomarkers for disease monitoring. Preclinical studies have shown that small-molecule activators (e.g., Urolithin A, Spermidine) and mitochondria-targeted antioxidants (e.g., MitoQ, SkQ1) can restore mitophagy and alleviate RPE damage. However, current evidence remains limited, as large-scale, long-term clinical trials are lacking. Challenges in drug delivery efficiency, safety, patient stratification, and clinical monitoring tools still hinder translation into practice. Future research should focus on biomarker-driven precision interventions, multicenter randomized controlled trials, and individualized therapeutic strategies. Overall, mitophagy research is transitioning from mechanistic exploration to clinical translation, with promising potential to enable early diagnosis, disease stratification, and precision management of AMD.
Immunoglobulin A nephropathy (IgAN) is an immune-mediated chronic inflammatory disease with a complex pathogenesis and diverse clinical manifestations. Currently, there is no specific treatment plan. Programmed cell death is an active and orderly way of cell death controlled by genes in the body, which maintains the homeostasis of the body and the development of organs and tissues by participating in various molecular signaling pathways. In recent years, programmed cell death has played an important regulatory role in the occurrence and development of IgAN, involving complex signaling pathways. Under pathological conditions, it may relieve kidney damage through various pathways such as reducing oxidative stress, inhibiting inflammation, and improving energy metabolism. This article provides a review of the research progress of IgAN in apoptosis, autophagy, pyroptosis, ferroptosis,and cuproptosis in order to provide new therapeutic targets for IgAN.
ObjectiveTo evaluate the effects of icariin on autophagy induced by low-concentration of glucocorticoid and exosome production in bone microvascular endothelial cells (BMECs).MethodsBMECs were isolated from femoral heads resected in total hip arthroplasty and then intervened with hydrocortisone of low concentration (0, 0.03, 0.06, 0.10 mg/mL), which were set as groups A, B, C, and D, respectively. On the basis of hydrocortisone intervention, 5×10?5 mol/L of icariin was added to each group (set as groups A1, B1, C1 and D1, respectively). Western blot was used to detect the expressions of microtubule-associated protein 1 light chain 3B (LC3B) and dead bone slice 1 (p62) after 24 hours. Exosomes were extracted from BMECs treated with icariin (intervention group) and without icariin (non-intervention group), and the diameter and concentration of exosomes were evaluated by nanoparticle tracking analysis technique. The total protein content of exosomes was detected by BCA method, and the expressions of proteins carried by exosomes including CD9, CD81, transforming growth factor β1 (TGF-β1), and vascular endothelial growth factor A (VEGFA) were assessed by Western blot. The BMECs were further divided into three groups: BMECs in the experimental group and the control group were co-cultured with exosomes secreted by BMECs treated with or without icariin, respectively; the blank control group was BMECs without exosome intervention. The three groups were treated with hydrocortisone and Western blot was used to detect the expressions of LC3B and p62. The scratching assay was used to detect cell migration ability; angiogenic ability of BMECs was also assessed.ResultsWith the increase of hydrocortisone concentration, the protein expression of LC3B-Ⅱ increased gradually, and the protein expression of p62 decreased gradually (P<0.01). Compared with group with same concentration of hydrocortisone, the protein expression of LC3B-Ⅱ decreased and the protein expression of p62 increased after the administration of icariin (P<0.01). The concentration of exosomes in the intervention group was significantly higher than that in the non-intervention group (t=?10.191, P=0.001); and there was no significant difference in exosome diameter and total protein content between the two groups (P>0.05). CD9 and CD81 proteins were highly expressed in the non-intervention group and the intervention group, and the relative expression ratios of VEGFA/CD9 and TGF-β1/CD9 proteins in the intervention group were significantly higher than those in the non-intervention group (P<0.01). After co-culture of exosomes, the protein expression of p62 increased in blank control group, control group, and experimental group, while the protein expression of LC3B-Ⅱ decreased. There were significant differences among groups (P<0.05). When treated with hydrocortisone for 12 and 24 hours, the scratch closure rate of the control group and experimental group was significantly higher than that of the blank control group (P<0.05), and the scratch closure rate of the experimental group was significantly higher than that of the control group (P<0.05). When treated with hydrocortisone for 4 and 8 hours, the number of lumens, number of sprouting vessels, and length of tubule branches in the experimental group and the control group were significantly greater than those in the blank control group (P<0.05); the length of tubule branches and the number of lumens in the experimental group were significantly greater than those in the control group (P<0.05).ConclusionIcariin and BMECs-derived exosomes can improve the autophagy of BMECs induced by low concentration of glucocorticoid.
ObjectiveTo investigate the role of autophagy-lysosomal system in skeletal muscle atrophy in rats with chronic obstructive pulmonary disease (COPD).
MethodsPassive cigarette smoking was used to establish COPD model. The mRNA and protein expression of FOXO transcription factor and autophagy-related genes Bnip3, Beclin1, p62, MAP-LC3Ⅱ/Ⅰ, Atg5 in extensor digitorum longus of rats were measured by real time PCR and Western blot. The changes of extensor digitorum longus tissue sections and lung tissue sections in the experimental group rats were observed under transmission electron microscopy.
ResultsCompared with the control group, the mRNA expression of FOXO transcription factor and autophagy-related genes Bnip3, Beclin1, p62, Atg5 in extensor digitorum longus of the experimental group group rats was significantly increased (all P<0.05, as for Bnip3, the P value between two groups <0.01); The mRNA expression of MAP-LC3Ⅱ/Ⅰwas not significantly different between two groups (P>0.05). The protein expression of FOXO, Bnip3, Beclin1, p62, MAP-LC3Ⅱ/Ⅰ, Atg5 significantly increased in the COPD group (all P<0.05, as for Bnip3, MAP-LC3Ⅱ/Ⅰ, Beclin1, the P values between two groups <0.01). Compared with the control group, autolysosome in extensor digitorum longus tissue sections of the experimental group rats increased and lung tissue fibrosis and more inflammatory cells were observed in lung tissue sections of the experimental group rats under transmission electron microscopy.
ConclusionThe mRNA and protein expressions of FOXO transcription factor and autophagy-related genes in extensor digitorum longus increase significantly in the experimental group rats, suggesting that the activity of autophagy-lysosomal system, which may be one mechanism of skeletal muscle atrophy in COPD.
ObjectiveTo summarize the role of chondrocyte mitochondrial homeostasis imbalance in the pathogenesis of osteoarthritis (OA) and analyze its application prospects. Methods The recent literature at home and abroad was reviewed to summarize the mechanism of mitochondrial homeostasis imbalance, the relationship between mitochondrial homeostasis imbalance and the pathogenesis of OA, and the application prospect in the treatment of OA. Results Recent studies have shown that mitochondrial homeostasis imbalance, which is caused by abnormal mitochondrial biogenesis, the imbalance of mitochondrial redox, the imbalance of mitochondrial dynamics, and damaged mitochondrial autophagy of chondrocytes, plays an important role in the pathogenesis of OA. Abnormal mitochondrial biogenesis can accelerate the catabolic reaction of OA chondrocytes and aggravate cartilage damage. The imbalance of mitochondrial redox can lead to the accumulation of reactive oxygen species (ROS), inhibit the synthesis of extracellular matrix, induce ferroptosis and eventually leads to cartilage degradation. The imbalance of mitochondrial dynamics can lead to mitochondrial DNA mutation, decreased adenosine triphosphate production, ROS accumulation, and accelerated apoptosis of chondrocytes. When mitochondrial autophagy is damaged, dysfunctional mitochondria cannot be cleared in time, leading to ROS accumulation, which leads to chondrocyte apoptosis. It has been found that substances such as puerarin, safflower yellow, and astaxanthin can inhibit the development of OA by regulating mitochondrial homeostasis, which proves the potential to be used in the treatment of OA. Conclusion The mitochondrial homeostasis imbalance in chondrocytes is one of the most important pathogeneses of OA, and further exploration of the mechanisms of mitochondrial homeostasis imbalance is of great significance for the prevention and treatment of OA.
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.
