PHYTOMEDICINE
·
2024
·
IF 6.7
Chengda Ren,Chengyu Hu,Ming Hu,Yan Wu,Yang Yang,Fang Lu
Background Melatonin is an antioxidant that also has anti-inflammatory effects. It has been reported to delay the progression of age-related macular degeneration (AMD), however, the mechanism has not been fully recognized. Purpose The aim of the present study was to investigate the effects of melatonin on sodium iodate (SI)-induced retinal degeneration and elucidate the specific mechanisms, then, provide novel targets in AMD treatment. Methods Retinal degeneration mouse model and in vitro retinal pigment epithelium (RPE) death model were established by SI treatment. Melatonin was administrated intraperitoneally at a concentration of 20, 40 or 80 mg/kg for in vivo study or treated at 48 h before SI treatment. To confirm the therapeutic effects of melatonin on mouse, the retinal structure and visual function were evaluated. The specific cell death rates were determined by CCK-8 assay, PI staining and protein level of RIPK3. The cytosolic or mitochondrial calcium levels were determined by Fluo-4AM or Rhod-2AM staining. Mitochondrial functions including mitochondrial dynamics, mitochondrial membrane potential, or mitochondrial permeability pore opening were evaluated. The proteins involved in endoplasmic reticulum (ER) stress were measured by western blot assay while the genes expression in calcium signaling pathway were measured by RT-qPCR. Results We show that melatonin protects RPE cells from necroptosis and NLRP3 inflammasome activation induced by SI. Mechanistically, melatonin suppresses ER stress and intracellular calcium overload triggered by SI through restoring the function of SERCA2. Silencing of SERCA2 or blocking of melatonin receptors inhibit the protective effects of melatonin. Melatonin reduces mitochondrial Ca 2+ levels and restores mitochondrial membrane potential. Constant mitochondrial Ca 2+ overload directly promote cell necroptosis through mitochondrial fission. Inhibition of mitochondrial fission by Mdivi-1 prevent necroptosis induced by SI without altering the level of mitochondrial Ca 2+ . Conclusions The results confirmed that melatonin protects RPE cells from SI-induced injury by regulates MT2/SERCA2/Ca 2+ axis. This study highlighted the potential of melatonin in the treatment of AMD and elucidated the mechanism and signaling pathway that mediate the protective effects.
研究领域:
眼科学
·
药理学
·
细胞生物学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Frontiers in Pharmacology
·
2020
·
IF 4.225
Liu Bo,Wang Dong,Luo Erfei,Hou Jiantong,Qiao Yong,Yan Gaoliang,Wang Qingjie,Tang Chengchun
Sarco-endoplasmic reticulum Ca2+ ATPase (SERCA) pumps take up Ca2+ from the cytoplasm to maintain the balance of intracellular Ca2+. A decline in expression or activity of SERCA results in persistent store-operated calcium entry (SOCE). In cardiomyocytes as well as vascular smooth muscle cells (SMCs), SERCA2 acts as an important regulator of calcium cycling. The purpose of this study is to identify and better understand the role of transglutaminases2 (TG2) as a key factor involved in SERCA2 serotonination (s-SERCA2) and to elucidate the underlying mechanism of action. Human pulmonary venous smooth muscle cell in normal pulmonary lobe were isolated and cultured in vitro. Establishment of hypoxic pulmonary hypertension model in wild type and TG2 knockout mice. SERCA2 serotonylation was analyzed by co-(immunoprecipitation) IP when the TG2 gene silenced or overexpressed under normoxia and hypoxia in vivo and in vitro. Intracellular calcium ion was measured by using Fluo-4AM probe under normoxia and hypoxia. Real-time (RT)-PCR and Western blot analyzed expression of TG2, TRPC1, and TRPC6 under normoxia and hypoxia. Bioactivity of cells were analyzed by using Cell Counting Kit (CCK)-8, flow cytometry, wound healing, RT-PCR, and Western blot under PST-2744 and cyclopiazonic acid. We confirmed that 1) hypoxia enhanced the expression and activity of TG2, and 2) hypoxia increased the basal intracellular Ca2+ concentration ([Ca2+]i) and SOCE through activating TRPC6 on human pulmonary vein smooth muscle cells (hPVSMC). Then, we investigated the effects of overexpression and downregulation of the TG2 gene on the activity of SERCA2, s-SERCA2, basal [Ca2+]i, and SOCE under normoxia and hypoxia in vitro, and investigated the activity of SERCA2 and s-SERCA2 in vivo, respectively. We confirmed that SERCA2 serotonylation inhibited the activity of SERCA2 and increased the Ca2+ influx, and that hypoxia induced TG2-mediated SERCA2 serotonylation both in vivo and in vitro. Furthermore, we investigated the effect of TG2 activity on the biological behavior of hPVSMC by using an inhibitor and agonist of SERCA2, respectively. Finally, we confirmed that chronic hypoxia cannot increase vessel wall thickness, the right ventricular systolic pressure (RVSP), and right ventricular hypertrophy index (RVHI) of vascular smooth muscle-specific Tgm2−/− mice. These results indicated that hypoxia promoted TG2-mediated SERCA2 serotonylation, thereby leading to inhibition of SERCA2 activity, which further increased the calcium influx through the TRPC6 channel. Furthermore, tissue-specific conditional TG2 knockout mice prevents the development of pulmonary hypertension caused by hypoxia. In summary, we uncovered a new target (TG2) for treatment of chronic hypoxic pulmonary hypertension (CHPH).
研究领域:
心血管生理学
·
分子生物学
·
药理学
·
细胞生物学
·
病理生理学
✓ 已验证
DOI
PubMed
高影响因子
Nature Chemical Biology
·
2024
·
IF 12.9
Gan Lu,Jiang Qiwei,Huang Dong,Wu Xueji,Zhu Xinying,Wang Lei,Xie Wei,Huang Jialuo,Fan Runzhu,Jing Yihang,Tang Guihua,Li Xiang David,Guo Jianping,Yin Sheng
Liver fibrosis is an urgent clinical problem without effective therapies. Here we conducted a high-content screening on a natural Euphorbiaceae diterpenoid library to identify a potent anti-liver fibrosis lead, 12-deoxyphorbol 13-palmitate (DP). Leveraging a photo-affinity labeling approach, apolipoprotein L2 (APOL2), an endoplasmic reticulum (ER)-rich protein, was identified as the direct target of DP. Mechanistically, APOL2 is induced in activated hepatic stellate cells upon transforming growth factor-β1 (TGF-β1) stimulation, which then binds to sarcoplasmic/ER calcium ATPase 2 (SERCA2) to trigger ER stress and elevate its downstream protein kinase R-like ER kinase (PERK)–hairy and enhancer of split 1 (HES1) axis, ultimately promoting liver fibrosis. As a result, targeting APOL2 by DP or ablation of APOL2 significantly impairs APOL2–SERCA2–PERK–HES1 signaling and mitigates fibrosis progression. Our findings not only define APOL2 as a novel therapeutic target for liver fibrosis but also highlight DP as a promising lead for treatment of this symptom.
研究领域:
药理学
·
分子生物学
·
肝病学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PHARMACOLOGICAL RESEARCH
·
2026
·
IF 12.2
Shixian Pi,Wanling Liu,Junyong Zhao,Hui Chen,Xianbin Luo,Shaofa Wu,Jiarou Song,Xun Chen,Xue Li,Wenjian Luo,Yirui Wang,Chuan Liu,Jun Ren,Tian Li,He Liu,Xiaoyong Tong,Zhexue Qin
Vascular calcification arises from osteogenic transdifferentiation of vascular smooth muscle cells (VSMC) driven by disordered calcium signaling. Sarcoplasmic/ER calcium ATPase 2 (SERCA2) maintains intracellular calcium homeostasis. Irreversible oxidation of SERCA2 Cys 674 (C674) indicates SERCA2 dysfunction. The impact of SERCA2 dysfunction on vascular calcification remains poorly understood. Here, we demonstrate that oxidized SERCA2 C674, a SERCA2 dysfunction marker, was elevated in the calcified arteries of mice and chronic kidney disease (CKD) patients. Heterozygous SERCA2 Cys674Ser knock-in (SKI) mice, a SERCA2 dysfunction model, exhibited aggravated aortic calcification in cholecalciferol (VitD3)-overloaded and 5/6 nephrectomy-induced CKD mice. SERCA2 dysfunction exacerbates calcification, mitochondrial impairment and calcium overload in cultured VSMC. Mechanistically, SERCA2 dysfunction increased mitochondria-associated endoplasmic reticulum membrane (MAM) formation. Furthermore, outer-mitochondrial translocator protein (TSPO) was identified to facilitate SERCA2 coupling to the IP3R1-Grp75-VDAC1-MCU complex at MAM. TSPO knockdown alleviated SERCA2 dysfunction-induced MAM formation and vascular calcification in SKI mice and cultured SKI VSMC, while TSPO overexpression aggravated these effects. Inhibition of the downstream mitochondrial calcium uniporter (MCU) reduced mitochondrial calcium overload and thus alleviated the pro-calcific effects of TSPO in SKI VSMC. In conclusion, SERCA2 dysfunction promotes TSPO-dependent MAM formation, which couples SERCA2 to the IP3R1-Grp75-VDAC1-MCU complex, causing mitochondrial impairment and calcium overload. This study uncovers the pivotal role of SERCA2 during vascular calcification, delineates the novel components of the MAM complex, and highlights potential therapeutic targets of vascular calcification.
✓ 已验证
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2024
·
IF 8.2
Jia-Gen Cui,Hao Zhang,Ming-Shan Chen,Jia-Xin Wang,Yi Zhao,Jin-Long Li
Phthalates (PAEs), especially di (2-ethylhexyl) phthalate (DEHP), are generally considered to have adverse impact on nervous system. The residue of DEHP in the environment has gradually become a widely concerned environmental problem due to its widespread use in plastic items. Lycopene (LYC) as the readily available natural antioxidant is considered to have the potential to alleviate exogenous poisons-induced nerve damage. However, there is currently a lack of strategies to alleviate the neurotoxicity caused by DEHP, and it is also unknown whether LYC can alleviate the neurotoxicity caused by DEHP. The experiment demonstrated that LYC had the potential to mitigate DEHP-induced mitochondrial damage in cerebellum. DEHP induced the disorder of Ca 2+ transport in cerebellum, thereby resulting in the imbalance of protein homeostasis. Such disruption in protein homeostasis further results in the overactivation of mitochondrial unfolded protein response (UPR mt ) and mitochondrial injury. Mechanistically, LYC could alleviate the imbalance of calcium homeostasis and protein homeostasis induced by DEHP via regulating inositol 1, 4, 5-trisphosphate receptor type1 (IP3R1) and sarco/endoplasmic reticulum Ca (2+)-ATPase 2 (SERCA2), further alleviating mitochondrial damage in cerebellum. Subsequently, the present study suggested the mechanism of cerebellar injury induced by DEHP, and provided a novel approach to treating DEHP-induced neurotoxicity.
研究领域:
神经科学
·
毒理学
·
药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）