ACTA PHARMACOLOGICA SINICA
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2022
·Vol. 44
·期 1
·234-243
·
IF 7.169
Jiang Kai-long,Liu Chang-mei,Nie Li-tong,Jiang Hai-ni,Xu Lei,Zhang Kun-zhi,Fan Li-xia,Gao An-hui,Lin Lu-ling,Wang Xiang-yu,Tan Ming-jia,Zhang Qi-qing,Zhou Yu-bo,Li Jia
Inositol-requiring enzyme 1α (IRE1α) is the most conserved endoplasmic reticulum (ER) stress sensor with two catalytic domains, kinase and RNase, in its cytosolic portion. IRE1α inhibitors have been used to improve existing clinical treatments against various cancers. In this study we identified toxoflavin (TXF) as a new-type potent small molecule IRE1α inhibitor. We used luciferase reporter systems to screen compounds that inhibited the IRE1α-XBP1s signaling pathway. As a result, TXF was found to be the most potent IRE1α RNase inhibitor with an IC 50 value of 0.226 μM. Its inhibitory potencies on IRE1α kinase and RNase were confirmed in a series of cellular and in vitro biochemical assays. Kinetic analysis showed that TXF caused time- and reducing reagent-dependent irreversible inhibition on IRE1α, implying that ROS might participate in the inhibition process. ROS scavengers decreased the inhibition of IRE1α by TXF, confirming that ROS mediated the inhibition process. Mass spectrometry analysis revealed that the thiol groups of four conserved cysteine residues (CYS-605, CYS-630, CYS-715 and CYS-951) in IRE1α were oxidized to sulfonic groups by ROS. In molecular docking experiments we affirmed the binding of TXF with IRE1α, and predicted its binding site, suggesting that the structure of TXF itself participates in the inhibition of IRE1α. Interestingly, CYS-951 was just near the docked site. In addition, the RNase IC 50 and ROS production in vitro induced by TXF and its derivatives were negative correlated ( r = −0.872). In conclusion, this study discovers a new type of IRE1α inhibitor that targets a predicted new alternative site located in the junction between RNase domain and kinase domain, and oxidizes conserved cysteine residues of IRE1α active sites to inhibit IRE1α. TXF could be used as a small molecule tool to study IRE1α’s role in ER stress.
研究领域:
药理学
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生物化学
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肿瘤学
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细胞生物学
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PubMed
高影响因子
Toxics
·
2025
·Vol. 13
·期 2
·129
·
IF 4.1
Liuxin Wang,Weiwei Cao,Ting Wu
Cadmium (Cd) is an important environmental pollutant that can enter the body and inflict kidney damage. Quercetin (Que) is a natural flavonoid compound that can alleviate kidney damage in Cd-treated rats, but the specific mechanism is unclear. Herein, 24 male Sprague–Dawley rats were divided into four groups, namely the control, Cd, Cd + Que, and Que groups. Four weeks later, the rats were anesthetized with ether and were euthanized; then, their blood was collected and their kidneys were removed. Renal function markers were measured. Kidney tissue structure was observed by HE staining, cell apoptosis was detected by the TUNEL method, and mRNA and protein expression levels in the IRE1α-XBP1 apoptosis signaling pathway were analyzed by RT-PCR and Western blotting. Results showed that the Cd treatment group exhibited decreased renal dysfunction and pathologic injury. Cd-induced tissue damage and cell apoptosis and significantly increased the mRNA and protein expression levels (p< 0.01) related to the IRE1α-XBP1 signaling pathway. Compared with the Cd group, the Cd + Que group exhibited increased renal dysfunction. Conversely, kidney tissue damage and renal cell apoptosis decreased, and the mRNA and protein expression levels of IRE1α and XBP1 significantly decreased (p< 0.01). Cd treatment inflicted renal damage. Therefore, Que can restore the kidney tissue damage and alleviate the cell apoptosis caused by Cd through the inhibition of the IRE1α-XBP1 signaling pathway.
研究领域:
环境毒理学
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药理学
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分子生物学
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DOI
PubMed
高影响因子
ONCOGENE
·
2024
·
IF 6.9
Zhang Tingting,Zhao Faming,Zhang Yi,Shi Ji-Hua,Cui Fengzhen,Ma Weixiang,Wang Kai,Xu Chuanrui,Zeng Qingping,Zhong Rong,Li Ningning,Liu Yong,Jin Yang,Sheng Xia
Liver-specific Ern1 knockout impairs tumor progression in mouse models of hepatocellular carcinoma (HCC). However, the mechanistic role of IRE1α in human HCC remains unclear. In this study, we show that XBP1s, the major downstream effector of IRE1α, is required for HCC cell survival both in vitro and in vivo. Mechanistically, XBP1s transactivates LEF1, a key co-factor of β-catenin, by binding to its promoter. Moreover, XBP1s physically interacts with LEF1, forming a transcriptional complex that enhances classical Wnt signaling. Consistently, the activities of XBP1s and LEF1 are strongly correlated in human HCC and with disease prognosis. Notably, selective inhibition of XBP1 splicing using an IRE1α inhibitor significantly repressed the viability of tumor explants as well as the growth of tumor xenografts derived from patients with distinct Wnt/LEF1 activities. Finally, machine learning algorithms developed a powerful prognostic signature based on the activities of XBP1s/LEF1. In summary, our study uncovers a key mechanistic role for the IRE1α-XBP1s pathway in human HCC. Targeting this axis could provide a promising therapeutic strategy for HCC with hyperactivated Wnt/LEF1 signaling.
研究领域:
癌症生物学
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分子生物学
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遗传学
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转化医学
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PubMed
高影响因子
CELL DEATH AND DIFFERENTIATION
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2025
·
IF 15.4
Wang Xiaolu,Wang Qianqian,Wang Hong,Cai Guodi,An Yana,Liu Peiqing,Zhou Huihao,Chen Hong-Wu,Ji Shufeng,Ye Jiantao,Wang Junjian
Clinical treatment options for triple-negative breast cancer (TNBC) are currently limited to chemotherapy because of a lack of effective therapeutic targets. Recent evidence suggests that long noncoding RNAs (lncRNAs) encode bioactive peptides or proteins, thereby playing noncanonical yet significant roles in regulating cellular processes. However, the potential of lncRNA-translated products in cancer progression remains largely unknown. In this study, we identified a previously undocumented small protein encoded by the lncRNA LINC02870 . This protein is localized at the endoplasmic reticulum (ER) and participates in ER stress, thus, we named it the endoplasmic reticulum stress protein (ERSP). ERSP was highly expressed in TNBC tissues, and elevated LINC02870 content was correlated with poor prognosis in TNBC patients. Loss of ERSP inhibited TNBC growth and metastasis both in vitro and in vivo. The pro-oncogenic effects of ERSP could be attributed to its selective activation of the IRE1α/XBP1s branch. ERSP enhances the unfolded protein response (UPR) by interacting with XBP1s, facilitating the nuclear accumulation of XBP1s, thereby promoting the expression of ER stress-related genes. These findings highlight the regulatory role of the lncRNA-encoded protein ERSP in ER stress and suggest that it is a potential therapeutic target for TNBC.
研究领域:
肿瘤学
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分子生物学
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癌症研究
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PubMed
高影响因子
ENVIRONMENT INTERNATIONAL
·
2024
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IF 10.3
Haining Du,Jiaxin Li,Xiangjuan Wei,Daqian Yang,Boya Zhang,Xingpei Fan,Meimei Zhao,Ruijiao Zhu,Ziyi Zhang,Yuxia Zhang,Xiaoyan Li,Ning Gu
Methylparaben (MP), a preservative widely used in daily supplies, exists in both the environment and the human body. However, the potential health risks posed by MP remain unclear. This study aimed to unravel the mechanisms by which MP disrupts glucose and lipid homeostasis. For this, we administered MP to mice and observed changes in glucose and lipid metabolism. MP exposure led to hyperglycemia, hyperlipidemia, visceral organ injury, and hepatic lipid accumulation. RNA sequencing results from mice livers indicated a close association between MP exposure and endoplasmic reticulum (ER) stress, inflammatory response, and glucose and lipid homeostasis. Western blotting and quantitative reverse transcription–polymerase chain reaction revealed that MP activated ER stress, particularly the inositol-requiring enzyme 1 (IRE1)/X-box binding protein 1 (XBP1) pathway, which further promoted the activation of the nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) pathways. The activation of these pathways phosphorylated insulin receptor substrate-1 (IRS1) (ser 307), resulting in decreased phosphorylation of protein kinase B (Akt) (ser 473), leading to insulin resistance. Additionally, MP exposure promoted lipogenesis through ER stress. To explore potential remedies, we administered the ER stress inhibitor 4-phenylbutyric acid (4-PBA) and the IRE1α-XBP1 pathway inhibitor toyocamycin to mice, both of which protected against metabolic disorders and organ injury caused by MP. These findings suggest that MP induces disruptions in glucose and lipid metabolism through ER stress, primarily through the IRE1α-XBP1 pathway.
研究领域:
毒理学
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代谢
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内分泌学
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分子生物学
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DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2024
·
IF 5.7
Shan Su,Xiaohong Liu,Min Zhu,Wen Liu,Jingyi Liu,Yujia Yuan,Fudong Fu,Zhiyong Rao,Jingping Liu,Yanrong Lu,Younan Chen
Nonalcoholic fatty liver disease (NAFLD), characterized by hepatic lipid deposition, is one of the most prevalent chronic metabolic disorders globally, and its pharmaceutical treatments are still limited. Excessive lipid accumulation triggers endoplasmic reticulum (ER) stress and autophagy flux dysfunction, which are important mechanisms for NAFLD. Trehalose (Tre), a natural disaccharide, has been identified to reduce hepatic steatosis and glucose intolerance. However, its underlying mechanisms for NAFLD remain unclear. In this study, a high-fat-diet (HFD)-induced mouse NAFLD model and a saturated fatty acid palmitic acid (PA)-stimulated cell model were constructed. The results indicated that Tre supplementation ameliorated hepatocyte lipid deposition in vitro, as well as hepatic steatosis and hyperlipidemia in vivo. Mechanistically, Tre alleviated both autophagy flux dysfunction and endoplasmic reticulum (ER) stress. Under the stimulation of HFD or PA, Tre remarkably increased the expression and nucleic translocation of the lysosomal master protein transcription factor EB (TFEB), while decreasing the accumulation of p62 and also decreasing the ER stress markers (inositol-requiring enzyme 1 (IRE1α), XBP-1, CHOP, and BIP). Similar results were observed in an ER stressor tunicamycin (TM)-induced in vivo and in vitro models. In addition, the transcriptomic analysis of NAFLD patients revealed significant differences in ER stress-related and autophagy-related biomarkers, including TFEB, ATG7, IRE1α, and CHOP. Molecular docking results demonstrated a strong affinity between Tre and both IRE1α and TFEB. Overall, Tre protected hepatocytes from lipotoxicity-related ER stress and autophagy dysfunction, and its regulatory effect on the IRE1α–TFEB signaling pathway may be a critical mechanism. These findings suggest that Tre, as a bioactive substance with significant medicinal potential, holds considerable promise for drug development and clinical application in treating NAFLD.
研究领域:
药理学
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分子生物学
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代谢紊乱
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肝病学
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DOI
PubMed
高影响因子
ONCOGENE
·
2024
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IF 6.9
Zhang Tingting,Zhao Faming,Hu Yanxia,Wei Jinlan,Cui Fengzhen,Lin Yahang,Jin Yang,Sheng Xia
Humans are widely exposed to phthalates, a major chemical plasticizer that accumulates in the liver. However, little is known about the impact of chronic phthalate exposure on liver cancer development. In this study, we applied a long-term cell culture model by treating the liver cancer cell HepG2 and normal hepatocyte L02 to environmental dosage of monobutyl phthalate (MBP), the main metabolite of phthalates. Interestingly, we found that long-term MBP exposure significantly accelerated the growth of HepG2 cells in vitro and in vivo, but barely altered the function of L02 cells. MBP exposure triggered reprogramming of lipid metabolism in HepG2 cells, where cholesterol accumulation subsequently activated the IRE1α-XBP1s axis of the unfolded protein response. As a result, the XBP1s-regulated gene sets and pathways contributed to the increased aggressiveness of HepG2 cells. In addition, we also showed that MBP-induced cholesterol accumulation fostered an immunosuppressive microenvironment by promoting tumor-associated macrophage polarization toward the M2 type. Together, these results suggest that environmental phthalates exposure may facilitate liver cancer progression, and alerts phthalates exposure to patients who already harbor liver tumors.
研究领域:
毒理学
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癌症生物学
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代谢学
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免疫学
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PubMed
高影响因子
NITRIC OXIDE-BIOLOGY AND CHEMISTRY
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2024
·
IF 3.2
Yuan Gao,Jiao Xu,Kaichuan He,Qi Guo,Lin Xiao,Sheng Jin,Danyang Tian,Xu Teng,Cuixia An,Hongmei Xue,Yuming Wu
Previous studies showed that hyperhomocysteinemia (HHcy) induced endothelial dysfunction by endoplasmic reticulum (ER) stress induction and autophagy stimulation. This study aimed to determine the effect of hydrogen sulfide (H 2 S) in homocysteine (Hcy)-induced endothelial dysfunction and observe the possible mechanism involved.Male Wistar rats (160-180g) were used and randomly divided into four groups: Control group, HHcy group, HHcy+Sodium hydrosulfide (NaHS) group and NaHS group. Rats were fed with 2% high methionine diet for 8 weeks to set up HHcy model. Plasma concentration of Hcy was measured by ELISA.Endothelium-dependent and non-endothelium-dependent vasodilation of rat renal arteries were determined by myograph.The protein expression of cystathionine-γ-lyase (CSE), ER stress-and autophagy-related proteins in renal arteries or human umbilical vein endothelial cells (HUVECs) were analyzed by western blotting. The endothelial function was impaired in HHcy rats and HUVECs. NaHS supplementation could improve the ACh-induced vasodilation, however it was eliminated by ER stress inducer Tunicamycin (TM) or autophagy inducer Rapamycin. Western blotting in renal arteries showed that Glucose-regulated protein 78 (GRP78) and three branches of ER stress (p-IRE1α, p-PERK, ATF6, GRP78) and p-JNK1+p-JNK2 was downregulated by NaHS administration, simultaneously the autophagy marker Beclin1, LC3BII/LC3BI ratio was decreased and p62 was increased in HHcy rats. In HUVECs, IRE1α-JNK induced autophagy was involved in HHcy-induced endothelial dysfunction, while NaHS stimulation decreased the protein expression in IRE1α/JNK-autophagy pathway with Hcy incubation. This study might suggest that endothelial dysfunction induced by HHcy might be correlate with IRE1α-JNK-autophagy axis pathway, which was suppressed by exogenous supplementation of H 2 S donor NaHS.
研究领域:
心血管疾病
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分子生物学
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药理学
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细胞生物学
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DOI
PubMed
高影响因子
Nature Communications
·
2026
·
IF 18.1
Jianwei Cao,Xudong Zhao,Yunxin Xu,Chen Yang,Yazhen Huo,Ting Li,Wenjia Gu,Lei Wang,Youjun Wang,Likun Wang
The unfolded protein response (UPR) triggered by endoplasmic reticulum (ER) stress can be both pro-survival or pro-apoptotic, depending on the duration and intensity of the stress. ER stress under (patho)physiological conditions can last for long time, yet the dynamic regulation of the UPR under prolong ER stress is largely unknown. Here, we characterized the UPR dynamics during pharmacologically induced long-term ER stress and revealed an “up-down-up” fluctuation pattern of the IRE1α signal in various types of cells. A fluctuation of the calreticulin-IRE1α interaction intensity orchestrates dynamic regulation of IRE1α activity, which negatively correlates with the intensity of the interaction between IRE1α and BIP, a known suppressor of IRE1α. The calreticulin-IRE1α interaction is negatively affected by Ca 2+ concentration, which showed “down-up-down” pattern in the ER lumen over time. Furthermore, a circadian rhythmic fluctuation of calreticulin-IRE1α interaction intensity is observed in mouse liver, accompanied by oscillation of IRE1α phosphorylation level at regular physiological conditions. Our study suggests a calcium-mediated, calreticulin-driven IRE1α activity fluctuation, representing an intermediate status that the cell adopts to cope with chronic ER stress that may exist under both pathophysiological and physiological conditions. Ca 2+ concentration-mediated, seesawed interactions between IRE1α and two chaperones, CALR and BIP, were discovered to drive IRE1α activity fluctuation that was observed under chronic endoplasmic reticulum stress and physiological circadian conditions.
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DOI
PubMed
高影响因子
iScience
·
2025
·Vol. 28
·期 8
·
IF 4.1
Ruoxi Shi,Ming Wang,Si Chen,Xinwei Hu,Xudong Zhao,Shixin Zhou,Congli Fan,Zihan Zhou,Likun Wang
IRE1α and its downstream XBP1 signal is the most conserved unfolded protein response pathway that cells utilize to combat endoplasmic reticulum stress, also known to be utilized by tumor cells to adapt to harsh environment, leading to tumor progression. Several inhibitors against IRE1α have been developed, some of which show promising effect in clinical trial for cancer therapy, but none of them have been used in practice. Considering that hyper-activation of IRE1α induces cell death, we hypothesize that activation of IRE1α could be an alternative way for tumor suppression. Here, we identified divalent manganese ion as a potent activator to IRE1α, which interacts with the cytosolic part of IRE1α directly, augmenting the downstream pro-apoptotic pathway but not the pro-survival outcome. Mn 2+ limits tumor growth in xenograft model in an IRE1α-dependent way. Our finding suggests pharmacological activation of IRE1α as an underestimated but promising way in cancer therapy.
研究领域:
癌症生物学
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分子肿瘤学
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细胞信号传导
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药理学
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DOI
PubMed
高影响因子
INTERNATIONAL IMMUNOPHARMACOLOGY
·
2026
·
IF 5.6
Hao Li,Zhenyu Guan,Wendong Li,Xiaodan Zhang,Hongwei Tang,Jianjun Yang,Wenzhi Guo,Mingjie Ding
Background Hepatic ischemia-reperfusion injury (HIRI) remains a clinical challenge during liver surgery and transplantation, largely due to the lack of effective pharmacological interventions. Isolinderalactone (ILL), a sesquiterpene lactone, exhibits potent antioxidant and anti-inflammatory properties. However, its therapeutic potential for HIRI and its precise molecular targets, particularly regarding the SIRT1/IRE1α-mediated endoplasmic reticulum stress (ERS) pathway, remain to be elucidated. Objective This study aimed to determine the hepatoprotective effects of ILL against HIRI and investigate its regulatory mechanism centered on the SIRT1/IRE1α signaling axis. Methods HIRI was modeled in mice via ischemia/reperfusion (I/R) and in AML12 cells via hypoxia/reoxygenation (H/R). Cellular injury, oxidative stress, endoplasmic reticulum stress (ERS), apoptosis, and inflammatory responses were assessed using biochemical, histological, molecular, and cellular imaging techniques. The physical and functional interaction between ILL and SIRT1 was characterized through molecular docking, dynamics simulations, surface plasmon resonance, and enzymatic activity assays. The role of SIRT1 was further validated using genetic knockdown and pharmacological inhibition (EX527). Results ILL treatment significantly attenuated liver tissue damage, restored intracellular redox homeostasis, and mitigated ERS-induced inflammation and apoptosis. Mechanistically, ILL not only upregulated SIRT1 expression but also directly bound to SIRT1 to enhance its deacetylase activity, thereby suppressing the downstream IRE1α/TRAF2/JNK signaling cascade. Notably, SIRT1 silencing or pharmacological blockade with EX527 significantly blunted, albeit did not completely abolish, the protective effects of ILL, indicating that the SIRT1/IRE1α axis serves as a primary, though not exclusive, mediator of ILL's hepatoprotective activity. Conclusion ILL attenuates HIRI by simultaneously elevating SIRT1 expression and activating its deacetylase function, thereby restraining IRE1α-dependent ERS and subsequent hepatic injury. These findings highlight ILL as a promising therapeutic candidate for the management of perioperative HIRI.
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高影响因子
Cell Death & Disease
·
2025
·Vol. 16
·期 1
·1-15
·
IF 9.6
Cen Junjie,Zhao Dongliang,Shi Xin,Chen Jinlong,Zhou Hang,Liang Yanping,Gui Chengpeng,Chen Wei,Luo Junhang,Chen Xu
Renal cell carcinoma (RCC) remains a significant clinical challenge due to its increasing incidence and resistance to conventional therapy. This study identifies an unprecedented mechanism by which mesencephalic astrocyte-derived neurotrophic factor (MANF) contributes to RCC progression. From single-cell transcriptome, we observed a significant upregulation of MANF in RCC compared to its progenitor cells, the proximal tubular cells. Mechanistically, decreased N6-methyladenosine (m6A) modification on MANF mRNA, mediated by the upregulation of the m6A demethylase ALKBH5, led to reduced RNA degradation and increased MANF protein expression. Furthermore, while the common von Hippel-Lindau (VHL) deletion in RCC results in the accumulation of misfolded proteins and endoplasmic reticulum (ER) stress, increased MANF efficiently mitigated ER stress by binding to phosphorylated inositol-requiring enzyme-1 alpha (IRE1α) and inhibited its phosphorylation, indicating that MANF-mediated ER stress resistance compensates for the negative effects of VHL depletion and contributes to the survival of RCC. Our findings highlight a potential therapeutic strategy for RCC by targeting the m6A-mediated regulation, directly degrading MANF protein or inhibiting its function.
研究领域:
分子生物学
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癌症研究
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生物化学
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细胞生物学
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转化医学
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PubMed
高影响因子
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