1.Congrong San ameliorates cognitive impairment and neuroinflammation in rat model of Alzheimer's disease by alleviating endoplasmic reticulum stress to inhibit NLRP3 inflammasome activation.
Yuan-Qin CAI ; Yang XIANG ; Qing-Hua LONG ; Xi WANG ; Chu-Hua ZENG
China Journal of Chinese Materia Medica 2025;50(7):1881-1888
This study aims to investigate the effect of Congrong San(CRS) on endoplasmic reticulum stress-induced neuroinflammation in the rat model of Aβ_(1-42)-induced Alzheimer's disease(AD). Sixty male Sprague-Dawley rats(2 months old) were randomized into blank(CON), model(MOD), low-dose Congrong San(L-CRS), medium-dose Congrong San(M-CRS), high-dose Congrong San(H-CRS), and memantine hydrochloride(MJG) groups. The Morris water maze test was carried out to examine the learning and memory abilities of rats in each group. Hematoxylin-eosin staining and Nissl staining were employed to observe the morphology and number of CA1 neurons in the hippocampus of rats in each group. The morphology and structure of the endoplasmic reticulum in the hippocampus were observed by transmission electron microscopy. The immunofluorescence assay was employed to detect the expression of 78 kDa glucose-regulated protein(GRP78) in the hippocampus. Western blot was employed to determine the expression of apoptosis-associated speck-like protein containing a CARD(ASC), cysteinyl aspartate-specific proteinase(caspase-1), interleukin-18(IL-18), interleukin-1β(IL-1β), GRP78, and pathway proteins including protein kinase RNA-like endoplasmic reticulum kinase(PERK), phosphorylated PERK(p-PERK), C/EBP homologous protein(CHOP), and NOD-like receptor pyrin domain-containing protein 3(NLRP3) in the rat hippocampus. Compared with the MOD group, the M-CRS and H-CRS groups showed improved learning and memory abilities, reduced neuron losses in the hippocampus, alleviated endoplasmic reticulum stress, inhibited PERK-CHOP-NLRP3 pathway, and lowered levels of IL-1β, IL-6, and tumor necrosis factor-alpha(TNF-α). The results suggest that CRS can alleviate cognitive impairment and hippocampal neuron damage and reduce neuroinflammation in AD rats by alleviating endoplasmic reticulum stress to inhibit the activation of NLRP3 inflammasomes.
Animals
;
Endoplasmic Reticulum Stress/drug effects*
;
Male
;
Alzheimer Disease/psychology*
;
NLR Family, Pyrin Domain-Containing 3 Protein/metabolism*
;
Rats, Sprague-Dawley
;
Rats
;
Inflammasomes/genetics*
;
Drugs, Chinese Herbal/administration & dosage*
;
Cognitive Dysfunction/metabolism*
;
Disease Models, Animal
;
Hippocampus/drug effects*
;
Humans
;
Neuroinflammatory Diseases/drug therapy*
2.Effects of total flavonoids of Dracocephalum moldavica on apoptosis of H9c2 cells induced by OGD/R injury and endoplasmic reticulum stress.
Tian WANG ; Di-Wei LIU ; Tong-Ye WANG ; Xing-Yu ZHANG ; Jian-Guo XING ; Rui-Fang ZHENG
China Journal of Chinese Materia Medica 2025;50(5):1321-1330
This study investigated the effects of total flavonoids of Dracocephalum moldavica(TFDM) on apoptosis in rat H9c2 cells induced by endoplasmic reticulum stress(ERS) established by oxygen-glucose deprivation and reoxygenation(OGD/R) injury and tunicamycin(TM), and explored the potential mechanisms. After successful modeling, the following groups were set in this experiment: control group, model(OGD/R or TM) group, and TFDM low-, medium-, and high-dose groups(12.5, 25, and 50 μg·mL~(-1)). The OGD/R injury model was constructed in vitro. Cell proliferation was assessed using the cell counting kit-8(CCK-8) method. The levels of lactate dehydrogenase(LDH) and creatine kinase MB isoenzyme(CKMB) in the cell supernatant were detected. Western blot was used to assess the expression of ERS-related proteins, including glucose regulatory protein 78(GRP78), C/EBP homologous protein(CHOP), activating transcription factor 6(ATF6), and apoptotic proteins B-cell lymphoma 2(Bcl-2) and Bcl-2-associated X protein(Bax). Apoptosis was detected using the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling(TUNEL) method. In the TM-induced ERS model, Western blot was used to measure the expression of ERS pathway-related proteins GRP78, CHOP, inositol-requiring enzyme 1(IRE1), X-box binding protein 1(XBP1), protein kinase RNA-like endoplasmic reticulum kinase(PERK), eukaryotic initiation factor 2α(eIF2α), ATF6, p-ATF6, and apoptotic proteins Bcl-2, Bax, cysteinyl aspartate specific proteinase-12(caspase-12), and cleaved caspase-12. Gene expression of GRP78, CHOP, PERK, and ATF6 was detected by real-time fluorescence quantitative PCR(RT-qPCR). Apoptosis was again detected using the TUNEL method. The results showed that in the OGD/R model, compared with the control group, the levels of LDH and CKMB in the cell supernatant were significantly increased in the OGD/R group. Compared with the OGD/R group, the levels of LDH and CKMB in the TFDM group were significantly reduced. Western blot results revealed that compared with the control group, the expression of ERS-related proteins and Bax in the OGD/R group was significantly increased, while the expression of Bcl-2 was significantly decreased. Compared with the OGD/R group, the expression of ERS-related proteins and Bax in the TFDM groups was significantly reduced, and the expression of Bcl-2 was significantly increased. TUNEL assay showed that apoptosis was significantly decreased after TFDM treatment. In the TM-induced ERS experiment, compared with the control group, the expression of ERS-related genes, ERS-related proteins, and apoptotic proteins in the TM group was significantly increased, while the expression of Bcl-2 was significantly decreased. Compared with the TM group, the expression of ERS-related genes, ERS-related proteins, and apoptotic proteins in the TFDM group was significantly reduced, and the expression of Bcl-2 was significantly increased. These results suggest that ERS exists in the OGD/R-injured H9c2 cell model, and TFDM can effectively inhibit ERS-induced apoptosis. The mechanism may be related to the downregulation of ERS pathway-related proteins and apoptotic proteins.
Animals
;
Endoplasmic Reticulum Stress/drug effects*
;
Apoptosis/drug effects*
;
Rats
;
Flavonoids/pharmacology*
;
Glucose/metabolism*
;
Cell Line
;
Lamiaceae/chemistry*
;
Drugs, Chinese Herbal/pharmacology*
;
Oxygen/metabolism*
;
Reperfusion Injury/physiopathology*
;
Myocytes, Cardiac/cytology*
3.Mechanism of Yishen Jiangtang Decoction in regulating endoplasmic reticulum stress-mediated NLRP3 inflammasome to improve renal damage in diabetic nephropathy db/db mice.
Yun-Jie YANG ; Bin-Hua YE ; Chen QIU ; Han-Qing WU ; Bo-Wei HUANG ; Tong WANG ; Shi-Wei RUAN ; Fang GUO ; Jian-Ting WANG ; Ming-Qian JIANG
China Journal of Chinese Materia Medica 2025;50(10):2740-2749
This study aims to explore the mechanism through which Yishen Jiangtang Decoction(YSJTD) regulates endoplasmic reticulum stress(ERS)-mediated NOD-like receptor thermal protein domain associated protein 3(NLRP3) inflammasome to improve diabetic nephropathy(DN) in db/db mice. Thirty db/db mice were randomly divided into the model group, YSJTD group, ERS inhibitor 4-phenylbutyric acid(4-PBA) group, with 10 mice in each group. Additionally, 10 db/m mice were selected as the control group. The YSJTD group was orally administered YSJTD at a dose of 0.01 mL·g~(-1), the 4-PBA group was orally administered 4-PBA at a dose of 0.5 mg·g~(-1), and the control and model groups were given an equal volume of carboxylmethyl cellulose sodium. The treatments were administered once daily for 8 weeks. Food intake, water consumption, and body weight were recorded every 2 weeks. After the intervention, fasting blood glucose(FBG), glycosylated hemoglobin(HbA1c), urine microalbumin(U-mALB), 24-hour urine volume, serum creatinine(Scr), and blood urea nitrogen(BUN) were measured. Inflammatory markers interleukin-1β(IL-1β) and interleukin-18(IL-18) were detected using the enzyme-linked immunosorbent assay(ELISA). Renal pathology was assessed through hematoxylin-eosin(HE), periodic acid-Schiff(PAS), and Masson staining, and transmission electron microscopy(TEM). Western blot was used to detect the expression levels of glucose-regulated protein 78(GRP78), C/EBP homologous protein(CHOP), NLRP3, apoptosis-associated speck-like protein containing CARD(ASC), cysteinyl aspartate-specific proteinase(caspase-1), and gasdermin D(GSDMD) in kidney tissues. The results showed that compared to the control group, the model group exhibited poor general condition, increased weight and food and water intake, and significantly higher levels of FBG, HbA1c, U-mALB, kidney index, 24-hour urine volume, IL-1β, and IL-18. Compared to the model group, the YSJTD and 4-PBA groups showed improved general condition, increased body weight, decreased food intake, and lower levels of FBG, U-mALB, kidney index, 24-hour urine volume, and IL-1β. Specifically, the YSJTD group showed a significant reduction in IL-18 levels compared to the model group, while the 4-PBA group exhibited decreased water intake and HbA1c levels compared to the model group. Although there was a decreasing trend in water intake and HbA1c in the YSJTD group, the differences were not statistically significant. No significant differences were observed in BUN, Scr, and kidney weight among the groups. Renal pathology revealed that the model group exhibited more severe renal damage compared to the control group. Kidney sections from the model group showed diffuse mesangial proliferation in the glomeruli, tubular edema, tubular dilation, significant inflammatory cell infiltration in the interstitium, and increased glycogen staining and blue collagen deposition in the basement membrane. In contrast, the YSJTD and 4-PBA groups showed varying degrees of improvement in renal damage, glycogen staining, and collagen deposition, with the YSJTD group showing more significant improvements. TEM analysis indicated that the model group had extensive cytoplasmic edema, homogeneous thickening of the basement membrane, fewer foot processes, and widening of fused foot processes. In the YSJTD and 4-PBA groups, cytoplasmic swelling of renal tissues was reduced, the basement membrane remained intact and uniform, and foot process fusion improved.Western blot results indicated that compared to the control group, the model group showed upregulation of GRP78, CHOP, GSDMD, NLRP3, ASC, and caspase-1 expression. In contrast, both the YSJTD and 4-PBA groups showed downregulation of these markers compared to the model group. These findings suggest that YSJTD exerts a protective effect against DN by alleviating NLRP3 inflammasome activation through the inhibition of ERS, thereby improving the inflammatory response in db/db DN mice.
Animals
;
Endoplasmic Reticulum Stress/drug effects*
;
Diabetic Nephropathies/metabolism*
;
NLR Family, Pyrin Domain-Containing 3 Protein/genetics*
;
Drugs, Chinese Herbal/administration & dosage*
;
Mice
;
Inflammasomes/drug effects*
;
Male
;
Kidney/pathology*
;
Endoplasmic Reticulum Chaperone BiP
;
Humans
;
Interleukin-18/genetics*
;
Mice, Inbred C57BL
4.Glycyrrhetinic acid combined with doxorubicin induces apoptosis of human hepatocellular carcinoma HepG2 cells by regulating ERMMDs.
Ming-Shi PANG ; Xiu-Yun BAI ; Jue YANG ; Rong-Jun DENG ; Xue-Qin YANG ; Yuan-Yan LIU
China Journal of Chinese Materia Medica 2025;50(11):3088-3096
This study investigates the effect of glycyrrhetinic acid(GA) combined with doxorubicin(DOX) on apoptosis in HepG2 cells and its possible mechanisms. HepG2 cells were cultured in vitro, and cell viability was assessed using the cell counting kit-8(CCK-8) method. Flow cytometry was used to measure apoptosis levels in HepG2 cells. The cells were divided into the following groups: control group(0 μmol·L~(-1)), DOX group(2 μmol·L~(-1)), GA group(150 μmol·L~(-1)), and DOX + GA combination group(2 μmol·L~(-1) DOX + 150 μmol·L~(-1) GA), with treatments given for 24 hours. The colocalization level between the endoplasmic reticulum(ER) and mitochondria was assessed by colocalization fluorescence imaging. Fluorescence probes were used to measure the Ca~(2+) content in the ER and mitochondria. The qRT-PCR and Western blot were used to determine the mRNA and protein expression of sirtuin-3(SIRT3). Co-immunoprecipitation(CO-IP) was applied to investigate the interactions between voltage-dependent anion channel 1(VDAC1) and SIRT3, as well as between VDAC1, glucose-regulated protein 75(GRP75), and inositol 1,4,5-trisphosphate receptor(IP3R). The results showed that the combination of DOX and GA promoted apoptosis in HepG2 liver cancer cells. The colocalization level between the ER and mitochondria was significantly reduced, the Ca~(2+) content in the ER was significantly increased, and the Ca~(2+) content in the mitochondria was significantly decreased. The relative expression of VDAC1, GRP75, and IP3R was significantly reduced, and interactions between VDAC1, GRP75, and IP3R were observed. SIRT3 mRNA and protein expression levels were significantly increased, and an interaction between SIRT3 and VDAC1 was detected. The acetylation level of VDAC1 was significantly decreased. In conclusion, GA combined with DOX induces apoptosis in HepG2 cells by mediating the deacetylation of VDAC1 through SIRT3, weakening the interactions among VDAC1, GRP75, and IP3R. This regulates the formation of endoplasmic reticulum-mitochondrial membrane domains(ERMMDs), affects Ca~(2+) transport between the ER and mitochondria, and ultimately triggers cell apoptosis.
Humans
;
Apoptosis/drug effects*
;
Hep G2 Cells
;
Glycyrrhetinic Acid/pharmacology*
;
Doxorubicin/pharmacology*
;
Liver Neoplasms/genetics*
;
Carcinoma, Hepatocellular/physiopathology*
;
Mitochondria/metabolism*
;
Endoplasmic Reticulum/metabolism*
;
Cell Survival/drug effects*
;
Membrane Proteins/genetics*
5.Effect and mechanism of Buyang Huanwu Decoction in improving neurological function in ischemic stroke rats based on IRE1α/ASK1/JNK pathway.
Xin-Rong ZHANG ; Tian-Lang WANG ; Jia-Hao ZHANG ; Lu JIN ; Jian-Bo WANG ; Ya-Nan XUE ; Yi QU
China Journal of Chinese Materia Medica 2025;50(14):3857-3867
This study aimed to investigate the effect and mechanism of Buyang Huanwu Decoction in regulating endoplasmic reticulum stress via the inositol-requiring enzyme 1α(IRE1α)/apoptosis signal-regulating kinase 1(ASK1)/c-Jun N-terminal kinase(JNK) pathway to improve neurological function in rats with cerebral ischemia/reperfusion injury(CIRI). SPF-grade male sprague-dawley(SD) rats were randomly divided into Sham group, model group, Buyang Huanwu Decoction group, and edaravone group. Except for the Sham group, the other groups were subjected to the modified suture method to establish a middle cerebral artery occlusion/reperfusion(MCAO/R) model. After treatment, neurological function was assessed using the Zea Longa scoring system. Gait analysis was used to detect the motor function. Detection of relative infarct area in brain tissue using 2,3,5-triphenyltetrazolium chloride(TTC) staining. Nissl staining was used to observe the structure of neuronal cells. Western blot and real-time fluorescence quantitative PCR(RT-qPCR) were used to detect IRE1α, ASK1, JNK, B cell lymphoma-2(Bcl-2), Bcl-2 related X protein(Bax), and Caspase-3 in the brain tissue. Immunohistochemistry was used to detect the positive expression of IRE1α, ASK1, and JNK. Immunofluorescence was used to detect the fluorescence expression levels of Bax, Bcl-2, and Caspase-3. The results showed that compared with the Sham group, the model group exhibited increased neurological scores(P<0.01), increased ratio of ground contact area and strength in both forelimbs(P<0.01), enlarged relative infarct area of brain tissue(P<0.05), and a reduced number of Nissl staining-positive cells(P<0.01). The protein and mRNA expression levels of IRE1α, ASK1, JNK, Bax, and Caspase-3 in brain tissue were significantly elevated, while those of Bcl-2 were decreased(P<0.05). Compared with the model group, both the Buyang Huanwu Decoction group and edaravone group showed reduced neurological scores(P<0.05), decreased ratio of ground contact area and strength in both forelimbs(P<0.05), smaller relative infarct area(P<0.05), alleviated neuronal damage, and increased number of Nissl staining-positive cells(P<0.05). The expression levels of IRE1α, ASK1, JNK, Bax, and Caspase-3 protein and mRNA in brain tissue were significantly reduced, while those of Bcl-2 were significantly increased(P<0.05). The results indicated that Buyang Huanwu Decoction can effectively improve brain injury in CIRI rats, and its mechanism of action may be related to regulating the endoplasmic reticulum stress IRE1α/ASK1/JNK signaling pathway.
Animals
;
Male
;
Rats, Sprague-Dawley
;
Protein Serine-Threonine Kinases/genetics*
;
Drugs, Chinese Herbal/administration & dosage*
;
Rats
;
MAP Kinase Kinase Kinase 5/genetics*
;
Ischemic Stroke/physiopathology*
;
Humans
;
MAP Kinase Signaling System/drug effects*
;
Apoptosis/drug effects*
;
Endoribonucleases/genetics*
;
JNK Mitogen-Activated Protein Kinases/genetics*
;
Endoplasmic Reticulum Stress/drug effects*
;
Multienzyme Complexes
6.Modulation of Ryanodine Receptors on Microglial Ramification, Migration, and Phagocytosis in an Alzheimer's Disease Mouse Model.
Yulin OUYANG ; Zihao CHEN ; Qiang HUANG ; Hai ZHANG ; Haolin SONG ; Xinnian WANG ; Wenxiu DONG ; Yong TANG ; Najeebullah SHAH ; Shimin SHUAI ; Yang ZHAN
Neuroscience Bulletin 2025;41(11):2063-2077
Microglial functions are linked to Ca2+ signaling, with endoplasmic reticulum (ER) calcium stores playing a crucial role. Microglial abnormality is a hallmark of Alzheimer's disease (AD), but how ER Ca2+ receptors regulate microglial functions under physiological and AD conditions remains unclear. We found reduced ryanodine receptor 2 (Ryr2) expression in microglia from an AD mouse model. Modulation of RyR2 using S107, a RyR-Calstabin stabilizer, blunted spontaneous Ca2+ transients in controls and normalized Ca2+ transients in AD mice. S107 enhanced ATP-induced migration and phagocytosis while reducing ramification in control microglia; however, these effects were absent in AD microglia. Our findings indicate that RyR2 stabilization promotes an activation state shift in control microglia, a mechanism impaired in AD. These results highlight the role of ER Ca2+ receptors in both homeostatic and AD microglia, providing insights into microglial Ca2+ malfunctions in AD.
Animals
;
Microglia/pathology*
;
Alzheimer Disease/pathology*
;
Phagocytosis/drug effects*
;
Ryanodine Receptor Calcium Release Channel/metabolism*
;
Disease Models, Animal
;
Mice
;
Cell Movement/drug effects*
;
Mice, Transgenic
;
Calcium Signaling/physiology*
;
Calcium/metabolism*
;
Mice, Inbred C57BL
;
Male
;
Endoplasmic Reticulum/metabolism*
7.Endoplasmic reticulum membrane remodeling by targeting reticulon-4 induces pyroptosis to facilitate antitumor immune.
Mei-Mei ZHAO ; Ting-Ting REN ; Jing-Kang WANG ; Lu YAO ; Ting-Ting LIU ; Ji-Chao ZHANG ; Yang LIU ; Lan YUAN ; Dan LIU ; Jiu-Hui XU ; Peng-Fei TU ; Xiao-Dong TANG ; Ke-Wu ZENG
Protein & Cell 2025;16(2):121-135
Pyroptosis is an identified programmed cell death that has been highly linked to endoplasmic reticulum (ER) dynamics. However, the crucial proteins for modulating dynamic ER membrane curvature change that trigger pyroptosis are currently not well understood. In this study, a biotin-labeled chemical probe of potent pyroptosis inducer α-mangostin (α-MG) was synthesized. Through protein microarray analysis, reticulon-4 (RTN4/Nogo), a crucial regulator of ER membrane curvature, was identified as a target of α-MG. We observed that chemically induced proteasome degradation of RTN4 by α-MG through recruiting E3 ligase UBR5 significantly enhances the pyroptosis phenotype in cancer cells. Interestingly, the downregulation of RTN4 expression significantly facilitated a dynamic remodeling of ER membrane curvature through a transition from tubules to sheets, consequently leading to rapid fusion of the ER with the cell plasma membrane. In particular, the ER-to-plasma membrane fusion process is supported by the observed translocation of several crucial ER markers to the "bubble" structures of pyroptotic cells. Furthermore, α-MG-induced RTN4 knockdown leads to pyruvate kinase M2 (PKM2)-dependent conventional caspase-3/gasdermin E (GSDME) cleavages for pyroptosis progression. In vivo, we observed that chemical or genetic RTN4 knockdown significantly inhibited cancer cells growth, which further exhibited an antitumor immune response with anti-programmed death-1 (anti-PD-1). In translational research, RTN4 high expression was closely correlated with the tumor metastasis and death of patients. Taken together, RTN4 plays a fundamental role in inducing pyroptosis through the modulation of ER membrane curvature remodeling, thus representing a prospective druggable target for anticancer immunotherapy.
Pyroptosis/immunology*
;
Humans
;
Endoplasmic Reticulum/immunology*
;
Animals
;
Nogo Proteins/antagonists & inhibitors*
;
Mice
;
Cell Line, Tumor
;
Xanthones/pharmacology*
;
Neoplasms/pathology*
;
Mice, Nude
8.Cardiomyocyte-specific long noncoding RNA Trdn-as induces mitochondrial calcium overload by promoting the m6A modification of calsequestrin 2 in diabetic cardiomyopathy.
Xiaohan LI ; Ling LIU ; Han LOU ; Xinxin DONG ; Shengxin HAO ; Zeqi SUN ; Zijia DOU ; Huimin LI ; Wenjie ZHAO ; Xiuxiu SUN ; Xin LIU ; Yong ZHANG ; Baofeng YANG
Frontiers of Medicine 2025;19(2):329-346
Diabetic cardiomyopathy (DCM) is a medical condition characterized by cardiac remodeling and dysfunction in individuals with diabetes mellitus. Sarcoplasmic reticulum (SR) and mitochondrial Ca2+ overload in cardiomyocytes have been recognized as biological hallmarks in DCM; however, the specific factors underlying these abnormalities remain largely unknown. In this study, we aimed to investigate the role of a cardiac-specific long noncoding RNA, D830005E20Rik (Trdn-as), in DCM. Our results revealed the remarkably upregulation of Trdn-as in the hearts of the DCM mice and cardiomyocytes treated with high glucose (HG). Knocking down Trdn-as in cardiac tissues significantly improved cardiac dysfunction and remodeling in the DCM mice. Conversely, Trdn-as overexpression resulted in cardiac damage resembling that observed in the DCM mice. At the cellular level, Trdn-as induced Ca2+ overload in the SR and mitochondria, leading to mitochondrial dysfunction. RNA-seq and bioinformatics analyses identified calsequestrin 2 (Casq2), a primary calcium-binding protein in the junctional SR, as a potential target of Trdn-as. Further investigations revealed that Trdn-as facilitated the recruitment of METTL14 to the Casq2 mRNA, thereby enhancing the m6A modification of Casq2. This modification increased the stability of Casq2 mRNA and subsequently led to increased protein expression. When Casq2 was knocked down, the promoting effects of Trdn-as on Ca2+ overload and mitochondrial damage were mitigated. These findings provide valuable insights into the pathogenesis of DCM and suggest Trdn-as as a potential therapeutic target for this condition.
Animals
;
Diabetic Cardiomyopathies/pathology*
;
RNA, Long Noncoding/genetics*
;
Myocytes, Cardiac/metabolism*
;
Mice
;
Calsequestrin/genetics*
;
Calcium/metabolism*
;
Male
;
Sarcoplasmic Reticulum/metabolism*
;
Methyltransferases/metabolism*
;
Mice, Inbred C57BL
;
Mitochondria, Heart/metabolism*
;
Disease Models, Animal
;
Mitochondria/metabolism*
9.Research progress on the mechanism of activating transcription factor 5 in regulating cellular inflammatory stress response.
Haiyun LEI ; Bao FU ; Xiaoyun FU
Chinese Critical Care Medicine 2025;37(5):499-504
Activating transcription factor 5 (ATF5) is a member of the activating transcription factor/cyclic adenosine monophosphate response element binding protein (ATF/CREB) family. As a stress-induced transcription factor, ATF5 plays a crucial role in cellular inflammatory stress responses. Under cellular inflammatory stress conditions, ATF5 maintains cell homeostasis and survival by regulating key genes in the mitochondrial unfolded protein response (UPRmt) and endoplasmic reticulum stress (ERS). As a key regulator in UPRmt, ATF5 senses mitochondrial stress and translocate to the nucleus to activate the transcription of UPRmt-related genes, thereby promoting mitochondrial function recovery. Meanwhile, in ERS, ATF5 maintains endoplasmic reticulum homeostasis by regulating the expression of genes related to protein folding, degradation, and apoptosis, determining cell survival or death. ATF5 plays a vital role in various cellular inflammatory stress responses. In infectious inflammation, ATF5 plays an important role in alleviating neuroinflammation and maintaining intestinal barrier function by regulating UPRmt. In inflammation related to degenerative diseases, ATF5 improves intervertebral disc degeneration and delays the progression of osteoarthritis by regulating UPRmt. In metabolic inflammation such as diabetes and obesity, ATF5 regulates UPRmt and ERS to maintain the function of pancreatic β-cells, controlling their survival or inducing apoptosis, thus influencing the progression of diabetes. ATF5 protects mitochondria in the kidneys, adipose tissue, and pancreas, slows the progression of diabetic nephropathy, and improves insulin sensitivity. Furthermore, in immune-related inflammation, ATF5 alleviates glomerulonephritis and promotes tissue repair by enhancing immune tolerance in dendritic cells. In summary, ATF5, as a key regulator in cellular inflammatory stress responses, maintains cell homeostasis through regulating UPRmt and ERS and determines cell fate. Its critical regulatory role in cellular inflammatory stress responses makes ATF5 a potential clinical therapeutic target. This article summarizes the structural features and translational regulatory mechanisms of ATF5, focusing on its role in cellular inflammatory stress responses, particularly its regulatory mechanisms in UPRmt and ERS, aiming to provide a theoretical basis for understanding ATF5's role in cell and organ protection and to offer new insights into the treatment of related inflammatory diseases.
Humans
;
Endoplasmic Reticulum Stress
;
Inflammation/metabolism*
;
Activating Transcription Factors/metabolism*
;
Unfolded Protein Response
;
Mitochondria/metabolism*
;
Apoptosis
;
Animals
10.Magnolol inhibits appetite and causes visceral fat loss through Growth/differentiation factor-15 (GDF-15) by activating transcription factor 4-CCAAT enhancer binding protein γ-mediated endoplasmic reticulum stress responses.
Keru CHENG ; Yanyun ZHOU ; Yilong HAO ; Shengyun WU ; Nanping WANG ; Peng ZHANG ; Yinfang WANG
Chinese Journal of Natural Medicines (English Ed.) 2025;23(3):334-345
Magnolol, a compound extracted from Magnolia officinalis, demonstrates potential efficacy in addressing metabolic dysfunction and cardiovascular diseases. Its biological activities encompass anti-inflammatory, antioxidant, anticoagulant, and anti-diabetic effects. Growth/differentiation factor-15 (GDF-15), a member of the transforming growth factor β superfamily, is considered a potential therapeutic target for metabolic disorders. This study investigated the impact of magnolol on GDF-15 production and its underlying mechanism. The research examined the pharmacological effect of magnolol on GDF-15 expression in vitro and in vivo, and determined the involvement of endoplasmic reticulum (ER) stress signaling in this process. Luciferase reporter assays, chromatin immunoprecipitation, and in vitro DNA binding assays were employed to examine the regulation of GDF-15 by activating transcription factor 4 (ATF4), CCAAT enhancer binding protein γ (CEBPG), and CCCTC-binding factor (CTCF). The study also investigated the effect of magnolol and ATF4 on the activity of a putative enhancer located in the intron of the GDF-15 gene, as well as the influence of single nucleotide polymorphisms (SNPs) on magnolol and ATF4-induced transcription activity. Results demonstrated that magnolol triggers GDF-15 production in endothelial cells (ECs), hepatoma cell line G2 (HepG2) and hepatoma cell line 3B (Hep3B) cell lines, and primary mouse hepatocytes. The cooperative binding of ATF4 and CEBPG upstream of the GDF-15 gene or the E1944285 enhancer located in the intron led to full-power transcription of the GDF-15 gene. SNP alleles were found to impact the magnolol and ATF4-induced transcription activity of GDF-15. In high-fat diet ApoE-/- mice, administration of magnolol induced GDF-15 production and partially suppressed appetite through GDF-15. These findings suggest that magnolol regulates GDF-15 expression through priming of promoter and enhancer activity, indicating its potential as a drug for the treatment of metabolic disorders.
Lignans/pharmacology*
;
Growth Differentiation Factor 15/metabolism*
;
Animals
;
Biphenyl Compounds/pharmacology*
;
Endoplasmic Reticulum Stress/drug effects*
;
Activating Transcription Factor 4/genetics*
;
Mice
;
Humans
;
Male
;
Magnolia/chemistry*
;
CCAAT-Enhancer-Binding Proteins/genetics*
;
Mice, Inbred C57BL

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