1.Cellular senescence in renal ischemia-reperfusion injury.
Chinese Medical Journal 2025;138(15):1794-1806
Acute kidney injury (AKI) affects more than 20% of hospitalized patients and is a significant contributor to morbidity and mortality, primarily due to ischemia-reperfusion injury (IRI), which is one of the leading causes of AKI. IRI not only exacerbates the immediate impact of AKI but also facilitates its progression to chronic kidney disease (CKD) and, in cases of preexisting CKD, to end-stage renal disease (ESRD). One of the critical pathological processes associated with IRI-AKI is cellular senescence, characterized by an irreversible arrest in the cell cycle, morphological and chromatin organization changes, altered transcriptional and metabolic profiles, and the development of a hypersecretory phenotype known as the senescence-associated secretory phenotype (SASP). The SASP amplifies senescence signals in surrounding normal cells through senescence-related pathways, contributing to tissue damage, fibrosis, and chronic inflammation. This review provides an overview of the defining features of senescent cells and explores the fundamental mechanisms underlying senescent cell generation following IRI. We elucidate the pivotal roles of cellular senescence in the transition from IRI-AKI to chronic kidney injury. Furthermore, we discuss emerging therapies targeting cellular senescence, including senolytics and senomorphics, which have shown promising results in both preclinical and clinical settings. These therapies position cellular senescence as a crucial target for the treatment of IRI in the kidneys. Additionally, advancements in single-cell sequencing technology and artificial intelligence-assisted drug screening are expected to accelerate the discovery of novel senescent biomarkers and synotherapeutics, paving the way for optimized and personalized therapeutic interventions.
Humans
;
Cellular Senescence/physiology*
;
Reperfusion Injury/pathology*
;
Acute Kidney Injury/pathology*
;
Animals
;
Kidney/metabolism*
;
Senescence-Associated Secretory Phenotype/physiology*
2.Exogenous administration of zinc chloride improves lung ischemia/reperfusion injury in rats.
Shu-Yuan WANG ; Jun-Peng XU ; Yuan CHENG ; Man HUANG ; Si-An CHEN ; Zhuo-Lun LI ; Qi-Hao ZHANG ; Yong-Yue DAI ; Li-Yi YOU ; Wan-Tie WANG
Acta Physiologica Sinica 2025;77(5):811-819
The aim of this study was to investigate the contribution of lung zinc ions to pathogenesis of lung ischemia/reperfusion (I/R) injury in rats. Male Sprague Dawley (SD) rats were randomly divided into control group, lung I/R group (I/R group), lung I/R + low-dose zinc chloride group (LZnCl2+I/R group), lung I/R + high-dose ZnCl2 group (HZnCl2+I/R group), lung I/R + medium-dose ZnCl2 group (MZnCl2+I/R group) and TPEN+MZnCl2+I/R group (n = 8 in each group). Inductively coupled plasma mass spectrometry (ICP-MS) was used to measure the concentration of zinc ions in lung tissue. The degree of lung tissue injury was analyzed by observing HE staining, alveolar damage index, lung wet/dry weight ratio and lung tissue gross changes. TUNEL staining was used to detect cellular apoptosis in lung tissue. Western blot and RT-qPCR were used to determine the protein expression levels of caspase-3 and ZIP8, as well as the mRNA expression levels of zinc transporters (ZIP, ZNT) in lung tissue. The mitochondrial membrane potential (MMP) of lung tissue was detected by JC-1 MMP detection kit. The results showed that, compared with the control group, the lung tissue damage, lung wet/dry weight ratio and alveolar damage index were significantly increased in the I/R group. And in the lung tissue, the concentration of Zn2+ was markedly decreased, while the cleaved caspase-3/caspase-3 ratio and apoptotic levels were significantly increased. The expression levels of ZIP8 mRNA and protein were down-regulated significantly, while the mRNA expression of other zinc transporters remained unchanged. There was also a significant decrease in MMP. Compared with the I/R group, both MZnCl2+I/R group and HZnCl2+I/R group exhibited significantly reduced lung tissue injury, lung wet/dry weight ratio and alveolar damage index, increased Zn2+ concentration, decreased ratio of cleaved caspase-3/caspase-3 and apoptosis, and up-regulated expression levels of ZIP8 mRNA and protein. In addition, the MMP was significantly increased in the lung tissue. Zn2+ chelating agent TPEN reversed the above-mentioned protective effects of medium-dose ZnCl2 on the lung tissue in the I/R group. The aforementioned results suggest that exogenous administration of ZnCl2 can improve lung I/R injury in rats.
Animals
;
Reperfusion Injury/pathology*
;
Male
;
Rats, Sprague-Dawley
;
Rats
;
Chlorides/administration & dosage*
;
Lung/pathology*
;
Zinc Compounds/administration & dosage*
;
Apoptosis/drug effects*
;
Caspase 3/metabolism*
;
Cation Transport Proteins/metabolism*
3.Kazinol B alleviates hypoxia/reoxygenation-induced hepatocyte injury by inhibiting the JNK signaling pathway.
Yi ZHU ; Junhui LI ; Min YANG ; Pengpeng ZHANG ; Cai LI ; Hong LIU
Journal of Central South University(Medical Sciences) 2025;50(2):181-189
OBJECTIVES:
Hypoxia/reoxygenation (H/R) injury is a critical pathological process during liver transplantation. Kazinol B has known anti-inflammatory, anti-apoptotic, and metabolic regulatory properties, but its protective mechanism in H/R-induced liver injury remains unclear. This study aims to investigate the protective effects and underlying mechanisms of Kazinol B in H/R-induced hepatocyte injury.
METHODS:
An ischemia-reperfusion model was established in healthy adult male Sprague-Dawley rats, and an in vitro H/R model was created using cultured hepatocytes. Hepatocytes were treated with Kazinol B (0-100 μmol/L) to assess cytotoxicity and protective effects. Cell viability was evaluated using the cell counting kit-8 (CCK-8) and lactate dehydrogenase (LDH) release assays. Expression of apoptosis-related proteins, B-cell lymphoma 2 (Bcl-2), Bcl-2-associated death promoter (Bad), and cleaved caspase-3, was detected by Western blotting. Reactive oxygen species (ROS) levels were assessed via fluorescence probes, and inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were measured using enzyme-linked immunosorbent assay (ELISA). TdT-mediated nick end labeling (TUNEL) staining was performed to assess DNA damage and apoptosis.
RESULTS:
Kazinol B had no significant effect on hepatocyte viability at 0-50 μmol/L, but showed cytotoxicity at 100 μmol/L (P<0.05). At 0.1-20 μmol/L, Kazinol B significantly improved cell survival, reduced LDH release, decreased apoptosis, and attenuated DNA damage (all P<0.001). At 10 μmol/L, Kazinol B markedly down-regulated Bad and cleaved caspase-3 (both P<0.05), and up-regulated Bcl-2 (P<0.01). It also dose-dependently reduced ROS levels and inflammatory cytokines TNF-α and IL-1β (all P<0.01). Both in vitro and in vivo, Kazinol B inhibited activation of the c-Jun N-terminal kinase (JNK) pathway without affecting extracellular regulated protein kinase (ERK) signaling (P>0.05). TUNEL staining showed that the protective effect of Kazinol B against apoptosis was partially reversed by the JNK agonist anisomycin (P<0.01).
CONCLUSIONS
Kazinol B mitigates hepatocyte injury induced by H/R by inhibiting the JNK signaling pathway. Its protective effect is associated with suppression of oxidative stress and inflammation, indicating its potential as a hepatoprotective agent.
Animals
;
Hepatocytes/pathology*
;
Rats, Sprague-Dawley
;
Male
;
Rats
;
Reperfusion Injury/prevention & control*
;
Apoptosis/drug effects*
;
Reactive Oxygen Species/metabolism*
;
MAP Kinase Signaling System/drug effects*
;
Cell Survival/drug effects*
;
Cell Hypoxia
;
Cells, Cultured
4.Liver X receptor attenuates renal ischemia-reperfusion injury in mice.
Ying-Zhi HUANG ; Zhi-Lin LUAN ; Shu-Jing LIU ; Cong ZHANG ; Wen-Hua MING ; Bao-Yin REN ; You-Fei GUAN ; Xiao-Yan ZHANG
Acta Physiologica Sinica 2024;76(6):927-936
Acute kidney injury (AKI) is a clinical syndrome characterized by a rapid decline in renal function. Renal ischemia-reperfusion injury (RIRI) is one of the main causes of AKI with the underlying mechanism incompletely clarified. The liver X receptors (LXRs), including LXRα and LXRβ, are members of the nuclear receptor superfamily. It has been shown that LXRs play an important role in regulating glucose and lipid metabolism, cholesterol efflux, and inflammation. The purpose of this study was to explore the role and mechanism of LXRs in RIRI. We determined the effects of LXR activation on renal function and histological changes in a mouse RIRI model and a cellular model of hypoxia/reoxygenation (H/R). In vivo results showed that LXRs agonist GW3965 significantly inhibited the increase of serum creatinine and urea nitrogen levels induced by RIRI. Both HE and PAS staining of kidney tissues revealed that GW3965 alleviated the morphological damages caused by RIRI. Immunohistochemical staining showed that GW3965 mitigated 4-HNE and GRP78 levels induced by RIRI. Furthermore, TUNEL assay indicated that GW3965 reduced RIRI-induced renal cell apoptosis. Quantitative real-time PCR (qPCR) analysis revealed that GW3965 attenuated RIRI-induced IL-6 and IL-1β mRNA expression. Compared with wild-type group, LXRα gene deficiency had little effect on RIRI-associated renal functional decline and morphological damages. Additionally, in vitro study demonstrated that GW3965 alleviated H/R-induced decrease of HK-2 human renal proximal tubule cell viability and restored the activity of superoxide dismutase (SOD) after H/R. Western blot results showed that GW3965 mitigated the increase of 4-HNE and GRP78 protein expression levels after H/R; However, knockdown of LXRβ using the small interfering RNA (siRNA) technique reduced cell viability compared to GW3965-treated group. Taken together, the LXRs agonist GW3965 significantly alleviates RIRI in mice possibly by reducing apoptosis, oxidative stress, endoplasmic reticulum stress and inflammation. These results also preliminarily confirm that the renal protective effects of LXRs agonists are dependent on LXRβ.
Animals
;
Liver X Receptors/genetics*
;
Reperfusion Injury/prevention & control*
;
Mice
;
Benzoates/pharmacology*
;
Benzylamines/pharmacology*
;
Male
;
Endoplasmic Reticulum Chaperone BiP
;
Mice, Inbred C57BL
;
Apoptosis
;
Acute Kidney Injury/prevention & control*
;
Kidney/pathology*
;
Humans
5.Maresin1 inhibits the NF-κB/caspase-3/GSDME signaling pathway to alleviate hepatic ischemia-reperfusion injury.
Hou Shuai ZENG ; Yun Bing WANG ; Liu Xuan Zi CHEN ; Peng ZHU
Chinese Journal of Hepatology 2023;31(6):594-600
Objective: To investigate the role of Maresin1 (MaR1) in hepatic ischemia-reperfusion injury (HIRI). Methods: The HIRI model was established and randomly divided into a sham operation group (Sham group), an ischemia-reperfusion group (IR group), and a MaR1 ischemia-reperfusion group (MaR1+IR group). MaR1 80ng was intravenously injected into each mouse's tail veins 0.5h before anesthesia. The left and middle hepatic lobe arteries and portal veins were opened and clamped. The blood supply was restored after 1h of ischemia. After 6h of reperfusion, the mice were sacrificed to collect blood and liver tissue samples. The Sham's group abdominal wall was only opened and closed. RAW267.4 macrophages were administered with MaR1 50ng/ml 0.5h before hypoxia, followed by hypoxia for 8h and reoxygenation for 2h, and were divided into the control group, the hypoxia-reoxygenation group (HR group), the MaR1 hypoxia-reoxygenation group (MaR1 + HR group), the Z-DEVD-FMK hypoxia-reoxygenation group (HR+Z group), the MaR1 + Z-DEVD-FMK hypoxia-reoxygenation group (MaR1 + HR + Z group), and the Con group without any treatment. Cells and the supernatant above them were collected. One-way analysis of variance was used for inter-group comparisons, and the LSD-t test was used for pairwise comparisons. Results: Compared with the Sham group, the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), interleukin (IL)-1β, and IL-18 in the IR group were significantly higher (P < 0.05), with remarkable pathological changes, while the level in the MaR1 + IR group was lower than before (P < 0.05), and the pathological changes were alleviated. Compared with the Con group, the HR group had higher levels of IL-1β and IL-18 (P < 0.05), while the MaR1 + HR group had lower levels of IL-1β and IL-18 (P < 0.05). Western blot showed that the expressions of caspase-3, GSDME, and GSDME-N were significantly higher in the HR group and IR group than in the other groups; however, the expression was lower following MaR1 pretreatment. The Z-DEVD-FMK exploration mechanism was inhibited by the expression of caspase-3 in HIRI when using MaR1. Compared with the HR group, the IL-1β and IL-18 levels and the expressions of caspase-3, GSDME, and GSDME-N in the HR + Z group were decreased (P < 0.05), while the expression of nuclear factor κB was increased, but following MaR1 pretreatment, nuclear factor κB was decreased. There was no significant difference in the results between the MaR1 + H/R group and the MaR1 + H/R + Z group (P > 0.05). Conclusion: MaR1 alleviates HIRI by inhibiting NF-κB activation and caspase-3/GSDME-mediated inflammatory responses.
Mice
;
Animals
;
NF-kappa B/metabolism*
;
Interleukin-18/metabolism*
;
Caspase 3/metabolism*
;
Liver/pathology*
;
Signal Transduction
;
Reperfusion Injury/metabolism*
6.Protective Mechanism of Cordyceps sinensis Treatment on Acute Kidney Injury-Induced Acute Lung Injury through AMPK/mTOR Signaling Pathway.
Ruo-Lin WANG ; Shu-Hua LIU ; Si-Heng SHEN ; Lu-Yong JIAN ; Qi YUAN ; Hua-Hui GUO ; Jia-Sheng HUANG ; Peng-Hui CHEN ; Ren-Fa HUANG
Chinese journal of integrative medicine 2023;29(10):875-884
OBJECTIVE:
To investigate protective effect of Cordyceps sinensis (CS) through autophagy-associated adenosine monophosphate-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) signaling pathway in acute kidney injury (AKI)-induced acute lung injury (ALI).
METHODS:
Forty-eight male Sprague-Dawley rats were divided into 4 groups according to a random number table, including the normal saline (NS)-treated sham group (sham group), NS-treated ischemia reperfusion injury (IRI) group (IRI group), and low- (5 g/kg·d) and high-dose (10 g/kg·d) CS-treated IRI groups (CS1 and CS2 groups), 12 rats in each group. Nephrectomy of the right kidney was performed on the IRI rat model that was subjected to 60 min of left renal pedicle occlusion followed by 12, 24, 48, and 72 h of reperfusion. The wet-to-dry (W/D) ratio of lung, levels of serum creatinine (Scr), blood urea nitrogen (BUN), inflammatory cytokines such as interleukin- β and tumor necrosis factor- α, and biomarkers of oxidative stress such as superoxide dismutase, malonaldehyde (MDA) and myeloperoxidase (MPO), were assayed. Histological examinations were conducted to determine damage of tissues in the kidney and lung. The protein expressions of light chain 3 II/light chain 3 I (LC3-II/LC3-I), uncoordinated-51-like kinase 1 (ULK1), P62, AMPK and mTOR were measured by Western blot and immunohistochemistry, respectively.
RESULTS:
The renal IRI induced pulmonary injury following AKI, resulting in significant increases in W/D ratio of lung, and the levels of Scr, BUN, inflammatory cytokines, MDA and MPO (P<0.01); all of these were reduced in the CS groups (P<0.05 or P<0.01). Compared with the IRI groups, the expression levels of P62 and mTOR were significantly lower (P<0.05 or P<0.01), while those of LC3-II/LC3-I, ULK1, and AMPK were significantly higher in the CS2 group (P<0.05 or P<0.01).
CONCLUSION
CS had a potential in treating lung injury following renal IRI through activation of the autophagy-related AMPK/mTOR signaling pathway in AKI-induced ALI.
Rats
;
Male
;
Animals
;
AMP-Activated Protein Kinases/metabolism*
;
Cordyceps/metabolism*
;
Rats, Sprague-Dawley
;
Kidney/pathology*
;
Acute Kidney Injury/metabolism*
;
Signal Transduction
;
TOR Serine-Threonine Kinases/metabolism*
;
Reperfusion Injury/metabolism*
;
Cytokines/metabolism*
;
Acute Lung Injury/drug therapy*
;
Mammals/metabolism*
7.Shenmai Injection Attenuates Myocardial Ischemia/Reperfusion Injury by Targeting Nrf2/GPX4 Signalling-Mediated Ferroptosis.
Sheng-Lan MEI ; Zhong-Yuan XIA ; Zhen QIU ; Yi-Fan JIA ; Jin-Jian ZHOU ; Bin ZHOU
Chinese journal of integrative medicine 2022;28(11):983-991
OBJECTIVE:
To examine the effect of Shenmai Injection (SMJ) on ferroptosis during myocardial ischemia reperfusion (I/R) injury in rats and the underlying mechanism.
METHODS:
A total of 120 SPF-grade adult male SD rats, weighing 220-250 g were randomly divided into different groups according to a random number table. Myocardial I/R model was established by occluding the left anterior descending artery for 30 min followed by 120 min of reperfusion. SMJ was injected intraperitoneally at the onset of 120 min of reperfusion, and erastin (an agonist of ferroptosis), ferrostatin-1 (Fer-1, an inhibitor of ferroptosis) and ML385 (an inhibitor of nuclear factor erythroid-2 related factor 2 (Nrf2)) were administered intraperitoneally separately 30 min before myocardial ischemia as different pretreatments. Cardiac function before ischemia, after ischemia and after reperfusion was analysed. Pathological changes in the myocardium and the ultrastructure of cardiomyocytes were observed, and the myocardial infarction area was measured. Additionally, the concentration of Fe2+ in heart tissues and the levels of creatine kinase-MB (CK-MB), troponin I (cTnl), malondialdehyde (MDA) and superoxide dismutase (SOD) in serum were measured using assay kits, and the expressions of Nrf2, glutathione peroxidase 4 (GPX4) and acyl-CoA synthetase long-chain family member 4 (ACSL4) were examined by Western blot.
RESULTS:
Compared with the sham group, I/R significantly injured heart tissues, as evidenced by the disordered, ruptured and oedematous myocardial fibres; the increases in infarct size, serum CK-MB, cTnI and MDA levels, and myocardial Fe2+ concentrations; and the decreases in SOD activity (P<0.05). These results were accompanied by ultrastructural alterations to the mitochondria, increased expression of ACSL4 and inhibited the activation of Nrf2/GPX4 signalling (P<0.05). Compared with I/R group, pretreatment with 9 mL/kg SMJ and 2 mg/kg Fer-1 significantly reduced myocardial I/R injury, Fe2+ concentrations and ACSL4 expression and attenuated mitochondrial impairment, while 14 mg/kg erastin exacerbated myocardial I/R injury (P<0.05). In addition, cardioprotection provided by 9 mL/kg SMJ was completely reversed by ML385, as evidenced by the increased myocardial infarct size, CK-MB, cTnI, MDA and Fe2+ concentrations, and the decreased SOD activity (P<0.05).
CONCLUSIONS
Ferroptosis is involved in myocardial I/R injury. Pretreatment with SMJ alleviated myocardial I/R injury by activating Nrf2/GPX4 signalling-mediated ferroptosis, thereby providing a strategy for the prevention and treatment of ischemic heart diseases.
Animals
;
Male
;
Rats
;
Coenzyme A
;
Creatine Kinase
;
Ferroptosis
;
Ligases
;
Malondialdehyde
;
Myocardial Infarction/drug therapy*
;
Myocardial Ischemia/drug therapy*
;
Myocardial Reperfusion Injury/pathology*
;
Myocytes, Cardiac/metabolism*
;
NF-E2-Related Factor 2/metabolism*
;
Phospholipid Hydroperoxide Glutathione Peroxidase
;
Rats, Sprague-Dawley
;
Superoxide Dismutase/metabolism*
;
Troponin I
8.Sufentanil promotes autophagy and improves ischemia -reperfusion -induced acute kidney injury via up -regulating microRNA -145.
Yan LU ; Zongfang PIAO ; Jianling LI ; Ling LI ; Ruhong LI
Journal of Central South University(Medical Sciences) 2022;47(10):1315-1323
OBJECTIVES:
Sufentanil has a good protective effect on myocardial and liver injury caused by ischemia reperfusion (IR), but its protective effect on kidney is still unclear. This study aims to investigate whether sufentanil can prevent IR-induced acute kidney injury (AKI) and to determine whether its efficacy is related to miR-145-mediated autophagy.
METHODS:
A total of 40 rats were randomly divided into 5 groups (n=8 in each group): A sham group, an IR group, a sufentanil group, a sufentanil+miR-145 inhibitor control group (an anti-NC group) and a sufentanil+miR-145 inhibitor group (an anti-miR-145 group). Except for the sham group, the other groups established a rat AKI model induced by IR. The sufentanil group, the sufentanil+anti-NC group, and the sufentanil+anti-miR-145 were injected with sufentanil (1 μg/kg) through femoral vein 30 min before ischemia. The sufentanil+anti-NC group and the sufentanil+anti-miR-145 group were injected with miR-145 inhibitor control or anti-miR-145 (80 mg/kg) through the tail vein before sufentanil pretreatment. The structure and function of kidneys harvested from the rats were evaluated, and the protein levels of autophagy-related proteins, oxidative stress levels, and apoptosis levels were measured.
RESULTS:
Compared with the IR group, the renal structure and function were improved in the sufentanil group. The levels of blood urea nitrogen (BUN), creatinine (Cr), urinary kidney injury molecule 1 (KIM-1), neutrophil gelatinase related lipid transporter (NGAL), tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6 and ROS were significantly decreased (all P<0.05). In addition, compared with the IR group, the levels of Beclin-1 and LC3 in renal tissues in the sufentanil group were significantly increased (both P<0.05), and the apoptosis in renal tissues was significantly reduced (P<0.05). Compared with the sufentanil+anti-NC group, the levels of BUN, Cr, KIM-1, NGAL, TNF-α, IL-1β, IL-6 and ROS in the sufentanil+anti-miR-145 group were significantly increased (all P<0.05), the levels of Beclin-1 and LC3 in renal tissues were significantly decreased (both P<0.05), and the apoptosis in renal tissues was significantly increased (P<0.05).
CONCLUSIONS
Sufentanil can prevent the AKI induced by IR, which is related to the up-regulation of miR-145-mediated autophagy.
Animals
;
Rats
;
Acute Kidney Injury/pathology*
;
Antagomirs
;
Autophagy
;
Beclin-1/metabolism*
;
Creatinine
;
Interleukin-6/metabolism*
;
Ischemia
;
Kidney/pathology*
;
Lipocalin-2
;
MicroRNAs/metabolism*
;
Reactive Oxygen Species
;
Reperfusion
;
Reperfusion Injury/metabolism*
;
Sufentanil/therapeutic use*
;
Tumor Necrosis Factor-alpha
;
Up-Regulation
9.Neuronal Death Mechanisms and Therapeutic Strategy in Ischemic Stroke.
Rui MAO ; Ningning ZONG ; Yujie HU ; Ying CHEN ; Yun XU
Neuroscience Bulletin 2022;38(10):1229-1247
Ischemic stroke caused by intracranial vascular occlusion has become increasingly prevalent with considerable mortality and disability, which gravely burdens the global economy. Current relatively effective clinical treatments are limited to intravenous alteplase and thrombectomy. Even so, patients still benefit little due to the short therapeutic window and the risk of ischemia/reperfusion injury. It is therefore urgent to figure out the neuronal death mechanisms following ischemic stroke in order to develop new neuroprotective strategies. Regarding the pathogenesis, multiple pathological events trigger the activation of cell death pathways. Particular attention should be devoted to excitotoxicity, oxidative stress, and inflammatory responses. Thus, in this article, we first review the principal mechanisms underlying neuronal death mediated by these significant events, such as intrinsic and extrinsic apoptosis, ferroptosis, parthanatos, pyroptosis, necroptosis, and autophagic cell death. Then, we further discuss the possibility of interventions targeting these pathological events and summarize the present pharmacological achievements.
Brain Ischemia/pathology*
;
Cell Death
;
Humans
;
Ischemic Stroke
;
Reperfusion Injury/pathology*
;
Stroke/pathology*
;
Tissue Plasminogen Activator/therapeutic use*
10.Xenon post-conditioning protects against spinal cord ischemia-reperfusion injury in rats by downregulating mTOR pathway and inhibiting endoplasmic reticulum stress-induced neuronal apoptosis.
Lan LUO ; Jia Qi TONG ; Lu LI ; Mu JIN
Journal of Southern Medical University 2022;42(8):1256-1262
OBJECTIVE:
The purpose of this study was to determine whether xenon post-conditioning affects mTOR signaling as well as endoplasmic reticulum stress (ERS)-apoptosis pathway in rats with spinal cord ischemia/reperfusion injury.
METHODS:
Fifty male rats were randomized equally into sham-operated group (Sham group), I/R model group (I/R group), I/R model+ xenon post-conditioning group (Xe group), I/R model+rapamycin (a mTOR signaling pathway inhibitor) treatment group (I/R+ Rapa group), and I/R model + xenon post- conditioning with rapamycin treatment group (Xe + Rapa group).. In the latter 4 groups, SCIRI was induced by clamping the abdominal aorta for 85 min followed by reperfusion for 4 h. Rapamycin (or vehicle) was administered by daily intraperitoneal injection (4 mg/kg) for 3 days before SCIRI, and xenon post-conditioning by inhalation of 1∶1 mixture of xenon and oxygen for 1 h at 1 h after initiation of reperfusion; the rats without xenon post-conditioning were given inhalation of nitrogen and oxygen (1∶ 1). After the reperfusion, motor function and histopathologic changes in the rats were examined. Western blotting and real-time PCR were used to detect the protein and mRNA expressions of GRP78, ATF6, IRE1α, PERK, mTOR, p-mTOR, Bax, Bcl-2 and caspase-3 in the spinal cord.
RESULTS:
The rats showed significantly lowered hind limb motor function following SCIRI (P < 0.01) with a decreased count of normal neurons, increased mRNA and protein expressions of GRP78, ATF6, IRE1α, PERK, and caspase-3, and elevated p-mTOR/mTOR ratio and Bax/Bcl-2 ratio (P < 0.01). Xenon post-conditioning significantly decreased the mRNA and protein levels of GRP78, ATF6, IRE1α, PERK and caspase-3 (P < 0.05 or 0.01) and reduced p-mTOR/mTOR and Bax/Bcl-2 ratios (P < 0.01) in rats with SCIRI; the mRNA contents and protein levels of GRP78 and ATF6 were significantly decreased in I/R+Rapa group (P < 0.01). Compared with those in Xe group, the rats in I/R+Rapa group and Xe+Rapa had significantly lowered BBB and Tarlov scores of the hind legs (P < 0.01), and caspase-3 protein level and Bax/Bcl-2 ratio were significantly lowered in Xe+Rapa group (P < 0.05 or 0.01).
CONCLUSION
By inhibiting ERS and neuronal apoptosis, xenon post- conditioning may have protective effects against SCIRI in rats. The mTOR signaling pathway is partially involved in this process.
Animals
;
Apoptosis
;
Caspase 3/metabolism*
;
Endoplasmic Reticulum Stress
;
Endoribonucleases/pharmacology*
;
Injections, Intraperitoneal
;
Male
;
Neurons/pathology*
;
Nitrogen/metabolism*
;
Oxygen/metabolism*
;
Protein Serine-Threonine Kinases
;
Proto-Oncogene Proteins c-bcl-2/metabolism*
;
RNA, Messenger/metabolism*
;
Random Allocation
;
Rats
;
Rats, Sprague-Dawley
;
Reperfusion Injury/metabolism*
;
Sirolimus/pharmacology*
;
Spinal Cord Ischemia/pathology*
;
TOR Serine-Threonine Kinases/metabolism*
;
Xenon/therapeutic use*
;
bcl-2-Associated X Protein/metabolism*

Result Analysis
Print
Save
E-mail