scholarly journals Protective Effect of Quercetin on Sodium Iodate-Induced Retinal Apoptosis through the Reactive Oxygen Species-Mediated Mitochondrion-Dependent Pathway

2021 ◽  
Vol 22 (8) ◽  
pp. 4056
Author(s):  
Yuan-Yen Chang ◽  
Yi-Ju Lee ◽  
Min-Yen Hsu ◽  
Meilin Wang ◽  
Shang-Chun Tsou ◽  
...  

Age-related macular degeneration (AMD) leads to gradual central vision loss and is the third leading cause of irreversible blindness worldwide. The underlying mechanisms for this progressive neurodegenerative disease remain unclear and there is currently no preventive treatment for dry AMD. Sodium iodate (NaIO3) has been reported to induce AMD-like retinal pathology in mice. We established a mouse model for AMD to evaluate the effects of quercetin on NaIO3-induced retinal apoptosis, and to investigate the pertinent underlying mechanisms. Our in vitro results indicated that quercetin protected human retinal pigment epithelium (ARPE-19) cells from NaIO3-induced apoptosis by inhibiting reactive oxygen species production and loss of mitochondrial membrane potential as detected by Annexin V-FITC/PI flow cytometry. We also evaluated the relative expression of proteins in the apoptosis pathway. Quercetin downregulated the protein expressions of Bax, cleaved caspase-3, and cleaved PARP and upregulated the expression of Bcl-2 through reduced PI3K and pAKT expressions. Furthermore, our in vivo results indicated that quercetin improved retinal deformation and increased the thickness of both the outer nuclear layer and inner nuclear layer, whereas the expression of caspase-3 was inhibited. Taken together, these results demonstrate that quercetin could protect retinal pigment epithelium and the retina from NaIO3-induced cell apoptosis via reactive oxygen species-mediated mitochondrial dysfunction, involving the PI3K/AKT signaling pathway. This suggests that quercetin has the potential to prevent and delay AMD and other retinal diseases involving NaIO3-mediated apoptosis.

Tumor Biology ◽  
2017 ◽  
Vol 39 (11) ◽  
pp. 101042831773145 ◽  
Author(s):  
Fatima Abdelmutaal Ahmed Omer ◽  
Najihah Binti Mohd Hashim ◽  
Mohamed Yousif Ibrahim ◽  
Firouzeh Dehghan ◽  
Maizatulakmal Yahayu ◽  
...  

Xanthones are phytochemical compounds found in a number of fruits and vegetables. Characteristically, they are noted to be made of diverse properties based on their biological, biochemical, and pharmacological actions. Accordingly, the apoptosis mechanisms induced by beta-mangostin, a xanthone compound isolated from Cratoxylum arborescens in the human promyelocytic leukemia cell line (HL60) in vitro, were examined in this study. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was done to estimate the cytotoxicity effect of β-mangostin on the HL60 cell line. Acridine orange/propidium iodide and Hoechst 33342 dyes and Annexin V tests were conducted to detect the apoptosis features. Caspase-3 and caspase-9 activities; reactive oxygen species; real-time polymerase chain reaction for Bcl-2, Bax, caspase-3, and caspase-9 Hsp70 genes; and western blot for p53, cytochrome c, and pro- and cleavage-caspase-3 and caspase-9 were assessed to examine the apoptosis mechanism. Cell-cycle analysis conducted revealed that β-mangostin inhibited the growth of HL60 at 58 µM in 24 h. The administration of β-mangostin with HL60 caused cell morphological changes related to apoptosis which increased the number of early and late apoptotic cells. The β-mangostin-catalyzed apoptosis action through caspase-3, caspase-7, and caspase-9 activation overproduced reactive oxygen species which downregulated the expression of antiapoptotic genes Bcl-2 and HSP70. Conversely, the expression of the apoptotic genes Bax, caspase-3, and caspase-9 were upregulated. Meanwhile, at the protein level, β-mangostin activated the formation of cleaved caspase-3 and caspase-9 and also upregulated the p53. β-mangostin arrested the cell cycle at the G0/G1 phase. Overall, the results for β-mangostin showed an antiproliferative effect in HL60 via stopping the cell cycle at the G0/G1 phase and prompted the intrinsic apoptosis pathway.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Jesse G. Meyer ◽  
Thelma Y. Garcia ◽  
Birgit Schilling ◽  
Bradford W. Gibson ◽  
Deepak A. Lamba

Abstract Age-related macular degeneration (AMD) is the leading cause of blindness in developed countries, and is characterized by slow retinal degeneration linked to chronic reactive oxygen species (ROS) in the retinal pigmented epithelium (RPE). The molecular mechanisms leading to RPE dysfunction in response to ROS are unclear. Here, human stem cell-derived RPE samples were stressed with ROS for 1 or 3 weeks, and both intracellular and secreted proteomes were quantified by mass spectrometry. ROS increased glycolytic proteins but decreased mitochondrial complex I subunits, as well as membrane proteins required for endocytosis. RPE secreted over 1,000 proteins, many of which changed significantly due to ROS. Notably, secreted APOE is decreased 4-fold, and urotensin-II, the strongest known vasoconstrictor, doubled. Furthermore, secreted TGF-beta is increased, and its cognate signaler BMP1 decreased in the secretome. Together, our results paint a detailed molecular picture of the retinal stress response in space and time.


Author(s):  
G.E. Korte ◽  
M. Marko ◽  
G. Hageman

Sodium iodate iv. damages the retinal pigment epithelium (RPE) in rabbits. Where RPE does not regenerate (e.g., 1,2) Muller glial cells (MC) forma subretinal scar that replaces RPE. The MC response was studied by HVEM in 3D computer reconstructions of serial thick sections, made using the STEREC0N program (3), and the HVEM at the NYS Dept. of Health in Albany, NY. Tissue was processed for HVEM or immunofluorescence localization of a monoclonal antibody recognizing MG microvilli (4).


Nutrients ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 379
Author(s):  
Luchuanyang Sun ◽  
Nobuyuki Miyaji ◽  
Min Yang ◽  
Edward M. Mills ◽  
Shigeto Taniyama ◽  
...  

Astaxanthin (AX) is a carotenoid that exerts potent antioxidant activity and acts in the lipid bilayer. This study aimed to investigate the effects of AX on muscle-atrophy-mediated disturbance of mitochondria, which have a lipid bilayer. Tail suspension was used to establish a muscle-atrophied mouse model. AX diet fed to tail-suspension mice prevented loss of muscle weight, inhibited the decrease of myofiber size, and restrained the increase of hydrogen peroxide (H2O2) production in the soleus muscle. Additionally, AX improved downregulation of mitochondrial respiratory chain complexes I and III in the soleus muscle after tail suspension. Meanwhile, AX promoted mitochondrial biogenesis by upregulating the expressions of adenosine 5′-monophosphate–activated protein kinase (AMPK) α-1, peroxisome proliferator–activated receptor (PPAR)-γ, and creatine kinase in mitochondrial (Ckmt) 2 in the soleus muscle of tail-suspension mice. To confirm the AX phenotype in the soleus muscle, we examined its effects on mitochondria using Sol8 myotubes derived from the soleus muscle. We found that AX was preferentially detected in the mitochondrial fraction; it significantly suppressed mitochondrial reactive oxygen species (ROS) production in Sol8 myotubes. Moreover, AX inhibited the activation of caspase 3 via inhibiting the release of cytochrome c into the cytosol in antimycin A–treated Sol8 myotubes. These results suggested that AX protected the functional stability of mitochondria, alleviated mitochondrial oxidative stress and mitochondria-mediated apoptosis, and thus, prevented muscle atrophy.


2021 ◽  
Vol 20 (1) ◽  
pp. 76-83
Author(s):  
Chi-Sen Chang ◽  
Yuh-Chiang Shen ◽  
Chi-Wen Juan ◽  
Chia-Lin Chang ◽  
Po-Kai Lin

The neuroprotective mechanisms of Crataegus pinnatifida extracts and crataegolic acid were studied using paraquat induced cytotoxicity in PC12 cells. C. pinnatifida extracts were prepared using hexane, ethyl acetate, and 95% ethanol. Additionally, crataegolic acid (also known as maslinic acid) was found in C. pinnatifida extracts. Assessment methods included the examinations of cytotoxicity, intracellular reactive oxygen species and calcium changes, activity of caspase-3 and α-synuclein, apoptotic cell death, and the expression levels of the B-cell lymphoma 2 (Bcl-2) and BCL2-associated X (Bax) proteins to investigate the neuroprotective mechanisms of C. pinnatifida extracts and its active component, crataegolic acid. The three extracts and crataegolic acid exhibited potent neuroprotective actions against paraquat induced PC12 cell apoptosis at 5–20µg/mL and 80–100µM concentrations, respectively. The key protective mechanisms included decreasing cell apoptosis, upregulating Bcl-2 protein levels, and downregulating Bax protein levels. The 95% ethanol extract also decreased paraquat induced reactive oxygen species production, calcium overloading, and caspase-3 and α-synuclein activities. The beneficial effects of these extracts could be explained by the active component, crataegolic acid that also inhibited paraquat-induced apoptosis through the suppression of reactive oxygen species generation and the caspase-3 signaling pathway.


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