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Aims: Endoplasmic reticulum (ER) degradation via autophagy is a process that maintains ER homeostasis when cells are in a state of stress and is associated with many diseases; however, the role of hypoxia inducible factor-1α (HIF-1α)-mediated ER degradation and the related regulatory pathway in acute kidney injury (AKI) still needs to be further established. Results: In the present study, an in vivo AKI model was induced in mice via the ischemia-reperfusion (IR) method. The results revealed that HIF-1α and BNIP3 were increased, and autophagy and ER degradation were activated in the kidneys of AKI mice, whereas HIF-1α knockout significantly inhibited BNIP3, autophagy and ER degradation, accompanied by aggravated kidney injury. Overexpression of HIF-1α in vitro significantly increased BNIP3, autophagy and ER degradation, whereas inhibition of BNIP3 significantly reversed the effects of HIF-1α. In addition, the in vitro inhibition of autophagy with chloroquine significantly reversed the effects of HIF-1α on cell apoptosis. Moreover, selectively overexpressing BNIP3 on the ER membrane significantly increased ER degradation via autophagy and decreased cell apoptosis in vitro . Innovation and Conclusion: These data indicate that HIF-1α/BNIP3-mediated ER degradation via autophagy in tubular cells protects against IR-induced AKI. Antioxid. Redox Signal. 42, 212-227.

Background: Enterovirus 71 (EV71) is one of the major causative agents of hand, foot, and mouth disease (HFMD), and can cause severe cerebral complications and even fatality in children younger than 5 years old. However, there is no specific medication for EV71 infection in clinical practice. Our previous studies had identified the 6-thioguanine (6-TG), an FDA-approved anticancer drug, as a potential antiviral agent, but its anti-EV71 activity is largely unknown, therefore, we aim to explore the antiviral effect of 6-TG on EV71., Results: 6-TG significantly suppressed EV71 mRNA level, VP1 protein expression, and viral progeny production in HT-29 cells. In EV71-infected HT-29 cells, the 50% cytotoxicity concentration of 6-TG (CC 50 ) was > 2000 µM and the 50% inhibitory concentration of 6-TG against EV71 (IC 50 ) was 0.9302 µM. Interestingly, the selectivity index (SI) value of 6-TG against EV71 was > 2150.1, which was higher than the SI value (> 66.7) of ribavirin. Mechanistically, 6-TG treatment reduced the expression of baculoviral IAP repeat containing 3 (BIRC3), and further inhibited EV71 replication by attenuating BIRC3-mediated the complete autophagy., Conclusions: 6-TG exerted a significant inhibitory effect on EV71 infection in vitro and prevented EV71-induced the complete autophagy by decreasing BIRC3 expression. Our work provided a basis for the further development of 6-TG as a therapy for EV71-associated HFMD., Competing Interests: Declarations. Ethics approval and consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Sepsis-induced acute kidney injury (S-AKI) is the most common type of acute kidney injury (AKI), accompanied by elevated morbidity and mortality rates. This study investigated the mechanism by which lipid droplets (LDs) degraded via autophagy (lipophagy)required for RAB7 regulated ferroptosis in the pathogenesis of S-AKI. Here, we constructed the S-AKI model in vitro and in vivo to elucidate the potential relationship of lipophagy and ferroptosis, and we first confirmed that the activation of lipophagy promoted renal tubular epithelial cell ferroptosis and renal damage in S-AKI. The results showed that lipopolysaccharide (LPS) induced a marked increase in lipid peroxidation and ferroptosis, which were rescued by ferrstain-1 (Fer-1), an inhibitor of ferroptosis. In addition, LPS induced the remarkable activation of RAB7-mediated lipophagy. Importantly, silencing RAB7 alleviated LPS-induced lipid peroxidation and ferroptosis. Thus, the present study demonstrated the potential significant role of ferroptosis and lipophagy in sepsis-induced AKI, and contributed to better understanding of the pathogenesis and treatment targets of AKI., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Autophagy-mediated lipotoxicity plays a critical role in the progression of diabetic nephropathy (DN), but the precise mechanism is not fully understood. Whether lipophagy, a selective type of autophagy participates in renal ectopic lipid deposition (ELD) and lipotoxicity in the kidney of DN is unknown. Here, decreased lipophagy, increased ELD and lipotoxcity were observed in tubular cells of patients with DN, which were accompanied with reduced expression of AdipoR1 and p-AMPK. Similar results were found in db/db mice, these changes were reversed by AdipoRon, an adiponectin receptor activator that promotes autophagy. Additionally, a significantly decreased level of lipophagy was observed in HK-2 cells, a human proximal tubular cell line treated with high glucose, which was consistent with increased lipid deposition, apoptosis and fibrosis, while were partially alleviated by AdipoRon. However, these effects were abolished by pretreatment with ULK1 inhibitor SBI-0206965, autophagy inhibitor chloroquine and enhanced by AMPK activator AICAR. These data suggested by the first time that autophagy-mediated lipophagy deficiency plays a critical role in the ELD and lipid-related renal injury of DN., (© 2021. The Author(s).)

Transforming growth factor β1 (TGF‑β1) is one of the most important fibrogenic factors promoting the activation of hepatic stellate cells (HSCs). Autophagy is a process used by cells to degrade and recycle cellular proteins. Although TGF‑β1 induces autophagy in several other cellular systems, the association between its effect on fibrogenesis and autophagy in HSCs have not been determined. Liver tissues from C57BL/6 mice and the mouse HSC line JS1 were analyzed. Acute and chronic liver injury models were induced by carbon tetrachloride (CCl4), and JS1 cells were stimulated by TGF‑β1 to assess the mechanism and relationship between autophagy and fibrosis. Liver tissues from acute and chronic injury models induced by CCl4 demonstrated evidence of increased autophagic activity, as assessed by the expression of the microtubule‑associated protein 1 light chain 3BII protein. TGF‑β1 stimulated the activation of JS1 cells and simultaneously increased autophagy flux. However, this effect was attenuated when autophagy was inhibited using chloroquine, 3‑methyladenine or lentiviral short hairpin RNA‑mediated knockdown of autophagy‑related gene 7. Furthermore, whether MAPK, including ERK, JNK and p38 MAPK cascades were associated with TGF‑β1‑induced autophagy in JS1 cells was determined. Subsequently, it was shown that the ERK inhibitor, PD98059, and JNK inhibitor, SP600125, were able to reverse TGF‑β1‑induced autophagy and fibrosis. The results of the present study suggest that TGF‑β1‑induced autophagy is involved in the activation of JS1 cells, possibly through activation of the ERK and JNK signaling pathways.

Objective: To investigate the effects of isoliensinine (Iso) on the proliferation, apoptosis and autophagy of colon cancer SW480 cells through PI3K/Akt/mTOR signaling pathway. Methods: Colon cancer SW480 cells were treated with 10, 20 and 40 μmol/L Iso, and the effects of Iso on the cell proliferation capacity, apoptosis and expressions of autophagy related proteins LC3 I, LC3II and p62 were detected by CCK-8, flow cytometry and Western blot, respectively. Then, SW480 cells were treated respectively with 20 μmol/L Iso and 25 μmol/L PI3K activator 740 Y-P, and the cells were divided into the control group, the 740 Y-P group, the Iso group and the Iso+740 Y-P group. The effects of 740 Y-P on the apoptosis and the expressions of LC3 I, LC3 II, p62, PI3K, p-PI3K, mTOR and p-mTOR proteins in each group were detected by flow cytometry and WB. Results: After treatments with 10, 20 and 40 μmol/L Iso, the proliferation capacity of SW480 cells was decreased significantly (all P<0.05); the apoptosis rate was increased significantly (all P<0.05); the expressions of LC3 II/LC3 I were up-regulated significantly (all P<0.05), and the expression of p26 protein was down-regulated significantly (all P<0.05). After treatments with Iso and 740 Y-P, compared with the control group, the apoptosis rate and LC3 II/LC3 I expression of the 740 Y-P group were decreased significantly (both P<0.05), while the expressions of p26, p-PI3K/PI3K and p-mTOR/mTOR were increased significantly (all P<0.05).The apoptosis rate and LC3 II/LC3 expression in the Iso group were increased (both P<0.05) and the expressions of p26, p-PI3K/PI3K and p-mTOR/mTOR were decreased (all P<0.05). Compared with the 740 Y-P group, the apoptosis rate and LC3 II/LC3 I expression were increased in the Iso+740 Y-P group (P<0.05), while the expressions of p26, p-PI3K/PI3K and p-mTOR/mTOR were decreased (all P<0.05). Compared with the Iso group, the apoptosis rate and LC3 II/LC3 I expression were decreased (both P<0.05), and the expressions of p26, p-PI3K/PI3K, and p-mTOR/mTOR were increased significantly (all P<0.05) in the Iso+740 Y-P group. Conclusion: Iso inhibits the proliferation and induces the apoptosis and autophagy of SW480 cells by inhibiting PI3K/Akt/mTOR signaling pathway. [ABSTRACT FROM AUTHOR]

Resveratrol, which is a natural polyphenol found in grapes, berries, peanuts, and medicinal plants, has previously been reported to perform several biological functions, including inhibition of hepatic fibrosis. Activated hepatic stellate cells (HSCs) are the major cellular source of matrix protein‐secreting myofibroblasts, which are the major drivers of liver fibrogenesis. Numerous studies on the protective effects of resveratrol against liver fibrosis have focused on the inhibition of HSC activation. Although the underlying mechanisms remain to be fully elucidated, the regulation of autophagy and apoptosis might be intimately related. The mouse HSC line JS1 was stimulated with resveratrol to assess the mechanism and relationship between autophagy and apoptosis. Resveratrol modulated JS1 cell viability in a dose‐dependent manner. Moreover, resveratrol inhibited JS1 cell activation and induced autophagy and apoptosis. This antifibrotic effect was attenuated when autophagy was inhibited using chloroquine (CQ) or 3‐methyladenine (3‐MA) or when apoptosis was inhibited using Z‐VAD‐FMK. Furthermore, whether the Sirtuin1 (SIRT1) and c‐Jun N‐terminal kinase (JNK) signaling pathways were associated with the resveratrol‐mediated induction of autophagy and apoptosis in JS1 cells was examined. The SIRT1 inhibitor EX527 reversed autophagy, and the JNK inhibitor SP600125 reversed both autophagy and apoptosis induced by resveratrol. These findings suggest that the SIRT1 and JNK signaling pathways may be involved in the resveratrol‐mediated inhibition of HSC activation by regulating autophagy and apoptosis. SIRT1 may be responsible for inducing autophagy, while JNK affects both autophagy and apoptosis. This study highlighted autophagy and apoptosis as therapeutic targets by which resveratrol can attenuate fibrosis. Practical applications: Resveratrol, which is a natural polyphenol found in grapes, berries, peanuts, and medicinal plants, has previously been reported to inhibit hepatic fibrosis. Since activated HSCs are the major drivers of liver fibrogenesis, many studies on the anti‐hepatic fibrosis effects of resveratrol have focused on inhibiting HSC activation. The objective of this study was to evaluate the inhibitory effect of resveratrol on HSC activation and focused on the mechanism by which resveratrol modulated autophagy and apoptosis in JS1 cells, a mouse immortalized HSC line. It was shown that resveratrol inhibited HSC activation by inducing autophagy and apoptosis in a dose‐dependent manner, and the mechanism may be associated with the SIRT1 and JNK signaling pathways. This study highlighted autophagy and apoptosis as therapeutic targets by which resveratrol can attenuate fibrosis. These findings may provide a new framework for understanding the mechanism by which resveratrol inhibits HSC activation. [ABSTRACT FROM AUTHOR]

The kidney is an energy-consuming organ, and cellular metabolism plays an indispensable role in kidney-related diseases. Caveolin-1 (Cav-1), a multifunctional membrane protein, is the main component of caveolae on the plasma membrane. Caveolae are represented by tiny invaginations that are abundant on the plasma membrane and that serve as a platform to regulate cellular endocytosis, stress responses, and signal transduction. However, caveolae have received increasing attention as a metabolic platform that mediates the endocytosis of albumin, cholesterol, and glucose, participates in cellular metabolic reprogramming and is involved in the progression of kidney disease. It is worth noting that caveolae mainly depend on Cav-1 to perform the abovementioned cellular functions. Furthermore, the mechanism by which Cav-1 regulates cellular metabolism and participates in the pathophysiology of kidney diseases has not been completely elucidated. In this review, we introduce the structure and function of Cav-1 and its functions in regulating cellular metabolism, autophagy, and oxidative stress, focusing on the relationship between Cav-1 in cellular metabolism and kidney disease; in addition, Cav-1 that serves as a potential therapeutic target for treatment of kidney disease is also described. [ABSTRACT FROM AUTHOR]

Contrast-induced acute kidney injury (CI-AKI) is a main cause of hospital-acquired renal failure. Nevertheless, limited measures have been shown to be effective for the treatment of CI-AKI. Here, we demonstrated that αKlotho, which is highly expressed in kidney, has therapeutic activity in CI-AKI. Our data showed that αKlotho expression levels were decreased both in the kidney and serum of CI-AKI mice. Administration of αKlotho protein protected the kidney and HK-2 cells against contrast-induced injury. Mechanistically, αKlotho reduced contrast-induced renal tubular cells pyroptosis by limiting NLRP3 inflammasome activation. Meanwhile, αKlotho up-regulated autophagy via inhibiting the AKT/mTOR pathway and decreased mitochondrial ROS level. Inhibition of autophagy blunted the suppression effect of αKlotho on NLRP3 inflammasome activation and cell pyroptosis in contrast-treated HK-2 cells. Taken together, our data suggest that αKlotho protein protects against CI-AKI through inhibiting NLRP3 inflammasome-mediated pyroptosis, which is likely by promoting autophagy. αKlotho may be a promising therapeutic strategy for CI-AKI. [Display omitted] [ABSTRACT FROM AUTHOR]