scholarly journals Oxidative stress and gamma radiation-induced cancellous bone loss with musculoskeletal disuse

2010 ◽  
Vol 108 (1) ◽  
pp. 152-161 ◽  
Author(s):  
Hisataka Kondo ◽  
Kenji Yumoto ◽  
Joshua S. Alwood ◽  
Rose Mojarrab ◽  
Angela Wang ◽  
...  

Exposure of astronauts in space to radiation during weightlessness may contribute to subsequent bone loss. Gamma irradiation of postpubertal mice rapidly increases the number of bone-resorbing osteoclasts and causes bone loss in cancellous tissue; similar changes occur in skeletal diseases associated with oxidative stress. Therefore, we hypothesized that increased oxidative stress mediates radiation-induced bone loss and that musculoskeletal disuse changes the sensitivity of cancellous tissue to radiation exposure. Musculoskeletal disuse by hindlimb unloading (1 or 2 wk) or total body gamma irradiation (1 or 2 Gy of 137Cs) of 4-mo-old, male C57BL/6 mice each decreased cancellous bone volume fraction in the proximal tibiae and lumbar vertebrae. The extent of radiation-induced acute cancellous bone loss in tibiae and lumbar vertebrae was similar in normally loaded and hindlimb-unloaded mice. Similarly, osteoclast surface in the tibiae increased 46% as a result of irradiation, 47% as a result of hindlimb unloading, and 64% as a result of irradiation + hindlimb unloading compared with normally loaded mice. Irradiation, but not hindlimb unloading, reduced viability and increased apoptosis of marrow cells and caused oxidative damage to lipids within mineralized tissue. Irradiation also stimulated generation of reactive oxygen species in marrow cells. Furthermore, injection of α-lipoic acid, an antioxidant, mitigated the acute bone loss caused by irradiation. Together, these results showed that disuse and gamma irradiation, alone or in combination, caused a similar degree of acute cancellous bone loss and shared a common cellular mechanism of increased bone resorption. Furthermore, irradiation, but not disuse, may increase the number of osteoclasts and the extent of acute bone loss via increased reactive oxygen species production and ensuing oxidative damage, implying different molecular mechanisms. The finding that α-lipoic acid protected cancellous tissue from the detrimental effects of irradiation has potential relevance to astronauts and radiotherapy patients.

2021 ◽  
Vol 19 ◽  
Author(s):  
Tapan Behl ◽  
Gagandeep Kaur ◽  
Aayush Sehgal ◽  
Gokhan Zengin ◽  
Sukhbir Singh ◽  
...  

Background: Ionizing radiation from telluric sources is unceasingly an unprotected pitfall to humans. Thus, the foremost contributors to human exposure are global and medical radiations. Various pieces of evidences assembled during preceding years reveal the pertinent role of ionizing radiation-induced oxidative stress in the progression of neurodegenerative insults such as Parkinson’s disease, which have been contributing to increased proliferation and generation of reactive oxygen species. Objective: This review delineates the role of ionizing radiation-induced oxidative stress in Parkinson’s disease and proposes novel therapeutic interventions of flavonoid family offering effective management and slowing down the progression of Parkinson’s disease. Method: Published papers were searched via MEDLINE, PubMed, etc. published to date for in-depth database collection. Results: The potential of oxidative damage may harm the non-targeted cells. It can also modulate the functions of central nervous system, such as protein misfolding, mitochondria dysfunction, increased levels of oxidized lipids, and dopaminergic cell death, which accelerates the progression of Parkinson’s disease at the molecular, cellular, or tissue levels. In Parkinson’s disease, reactive oxygen species exacerbate the production of nitric oxides and superoxides by activated microglia, rendering death of dopaminergic neuronal cell through different mechanisms. Conclusion: Rising interest has extensively engrossed on the clinical trial designs based on the plant derived family of antioxidants. They are known to exert multifarious impact either way in neuroprotection via directly suppressing ionizing radiation-induced oxidative stress and reactive oxygen species production or indirectly increasing the dopamine levels and activating the glial cells.


Author(s):  
Durg V. Rai ◽  
Harcharan Singh Ranu

Ovarian hormone deficiency increases the generation of reactive oxygen species. Oxidative stress due to reactive oxygen species (ROS) can cause oxidative damage to cells. Cells have a number of defense mechanisms to protect themselves from the toxicity of ROS. There is increasing evidence of the role of free radicals in bone resorption and bone loss. Ovariectomised female wistar rats had been used as the animal model for the study of osteoporosis. Even though, there are studies portraying the role of free radicals in bone loss, the defense mechanism adapted by bone in ovariectomised animals remains obscure. So, the impact of ovariectomy on the bone antioxidant system in rats was investigated. Twenty female wistar rats were taken and divided into two groups: ovariectomised and control. It had been found that a significant (p<0.001) decrease in the activity of various enzymes like CAT (catalase), SOD (superoxide dismutase) (p<0.001), GST (glutathione-s-transferase). However, an increase in the malondialdehyde levels was found to be 30% in the ovariectomised rats as compared to the controls. Thus the study elucidates the oxidative stress in bone under ovariectomy.


2010 ◽  
Vol 22 (5) ◽  
pp. 856 ◽  
Author(s):  
Álvaro E. Domínguez-Rebolledo ◽  
María R. Fernández-Santos ◽  
Alfonso Bisbal ◽  
José Luis Ros-Santaella ◽  
Manuel Ramón ◽  
...  

Antioxidants could improve sperm media, extending the viability of spermatozoa and protecting their DNA. The protective ability of lipoic acid, melatonin, Trolox and crocin was tested on red deer spermatozoa incubated at 37°C. Cryopreserved spermatozoa were thawed and incubated with 1 mM or 0.1 mM of each antioxidant, with or without oxidative stress (100 μM Fe2+). Motility (CASA), viability, mitochondrial membrane potential and acrosomal status were assessed. Lipoperoxidation (malondialdehyde production), intracellular reactive oxygen species (ROS) and DNA status (TUNEL) were checked at 4 h. Incubation alone increased ROS and decreased motility. Oxidative stress intensified these effects, increasing lipoperoxidation and DNA damage. Lipoic acid had little protective effect, whereas 1 mM melatonin showed limited protection. Trolox lowered ROS and lipoperoxidation both in oxidised and non-oxidised samples. In oxidised samples, Trolox prevented DNA and acrosomal damage, and ameliorated motility. Crocin at 1 mM showed similar results to Trolox, but noticeably stimulated motility and had no effect on lipoperoxidation. In a second experiment, a broader range of crocin and melatonin concentrations were tested, confirming the effects of crocin (positive effects noticeable at 0.5–0.75 mM), but showing an increase in lipoperoxidation at 2 mM. Melatonin was increasingly effective at 2.5 and 5 mM (ROS, lipoperoxidation and DNA status). Crocin seems a promising new antioxidant, but its particular effects on sperm physiology must be further studied, especially the consequences of motility stimulation and confirming its effect on lipoperoxidation. Melatonin might be useful at relatively high concentrations, compared to Trolox.


Antioxidants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1294
Author(s):  
Stela Dragomanova ◽  
Simona Miteva ◽  
Ferdinando Nicoletti ◽  
Katia Mangano ◽  
Paolo Fagone ◽  
...  

Oxidative stress (OS), resulting from a disrupted balance between reactive oxygen species (ROS) and protective antioxidants, is thought to play an important pathogenetic role in several diseases, including viral infections. Alpha-lipoic acid (LA) is one of the most-studied and used natural compounds, as it is endowed with a well-defined antioxidant and immunomodulatory profile. Owing to these properties, LA has been tested in several chronic immunoinflammatory conditions, such as diabetic neuropathy and metabolic syndrome. In addition, a pharmacological antiviral profile of LA is emerging, that has attracted attention on the possible use of this compound for the cotreatment of several viral infections. Here, we will review the emerging literature on the potential use of LA in viral infections, including COVID-19.


2004 ◽  
Vol 71 ◽  
pp. 121-133 ◽  
Author(s):  
Ascan Warnholtz ◽  
Maria Wendt ◽  
Michael August ◽  
Thomas Münzel

Endothelial dysfunction in the setting of cardiovascular risk factors, such as hypercholesterolaemia, hypertension, diabetes mellitus and chronic smoking, as well as in the setting of heart failure, has been shown to be at least partly dependent on the production of reactive oxygen species in endothelial and/or smooth muscle cells and the adventitia, and the subsequent decrease in vascular bioavailability of NO. Superoxide-producing enzymes involved in increased oxidative stress within vascular tissue include NAD(P)H-oxidase, xanthine oxidase and endothelial nitric oxide synthase in an uncoupled state. Recent studies indicate that endothelial dysfunction of peripheral and coronary resistance and conductance vessels represents a strong and independent risk factor for future cardiovascular events. Ways to reduce endothelial dysfunction include risk-factor modification and treatment with substances that have been shown to reduce oxidative stress and, simultaneously, to stimulate endothelial NO production, such as inhibitors of angiotensin-converting enzyme or the statins. In contrast, in conditions where increased production of reactive oxygen species, such as superoxide, in vascular tissue is established, treatment with NO, e.g. via administration of nitroglycerin, results in a rapid development of endothelial dysfunction, which may worsen the prognosis in patients with established coronary artery disease.


2018 ◽  
Vol 17 (2) ◽  
pp. 117-121
Author(s):  
Sun Maw-Sheng ◽  
Liang Chun-Ya ◽  
Hsieh Po-Chun ◽  
Kuo Chan-Yen

Apoptosis of hepatocyte, under ischemia/reperfusion (IR) conditions, has been identified as an essential process in the progression of liver transplantation. Under these conditions, mitochondria can become a threat to the cell because of their capacity to generate reactive oxygen species (ROS). Additionally, ROS overproduction may induce inflammation. As ROS accumulation appears to cause hepatocyte damage or death, there has been considerable interest in identifying the candidate natural products involved and in developing strategies to reduce oxidative stress. In this study, we use Danshensu as a candidate product to speculate whether has the protective effect on apoptotic hepatocyte upon IR. To speculate the apoptotic phenomena was reversed by Danshensu, we detected the p53, cleaved-caspase 3 expression by western blotting, as well as caspase-3 activity. Additionally, we analyzed the ROS levels by 2′,7′-dichlorofluorescin diacetate (DCF-DA) staining. We also detected the cell viability by WST-1. Results showed that Danshensu alleviated hypoxia-caused cell apoptosis via ROS overproduction. We suggested that Danshensu is a good strategy for treating hepatocyte damage upon IR.


2019 ◽  
Vol 2019 ◽  
pp. 1-16 ◽  
Author(s):  
Amnah M. Alshangiti ◽  
Eszter Tuboly ◽  
Shane V. Hegarty ◽  
Cathal M. McCarthy ◽  
Aideen M. Sullivan ◽  
...  

Neuroblastoma is an embryonal malignancy that arises from cells of sympathoadrenal lineage during the development of the nervous system. It is the most common pediatric extracranial solid tumor and is responsible for 15% of childhood deaths from cancer. Fifty percent of cases are diagnosed as high-risk metastatic disease with a low overall 5-year survival rate. More than half of patients experience disease recurrence that can be refractory to treatment. Amplification of the MYCN gene is an important prognostic indicator that is associated with rapid disease progression and a poor prognosis, highlighting the need for new therapeutic approaches. In recent years, there has been an increasing focus on identifying anticancer properties of naturally occurring chalcones, which are secondary metabolites with variable phenolic structures. Here, we report that 4-hydroxychalcone is a potent cytotoxin for MYCN-amplified IMR-32 and SK-N-BE (2) neuroblastoma cells, when compared to non-MYCN-amplified SH-SY5Y neuroblastoma cells and to the non-neuroblastoma human embryonic kidney cell line, HEK293t. Moreover, 4-hydroxychalcone treatment significantly decreased cellular levels of the antioxidant glutathione and increased cellular reactive oxygen species. In addition, 4-hydroxychalcone treatment led to impairments in mitochondrial respiratory function, compared to controls. In support of this, the cytotoxic effect of 4-hydroxychalcone was prevented by co-treatment with either the antioxidant N-acetyl-L-cysteine, a pharmacological inhibitor of oxidative stress-induced cell death (IM-54) or the mitochondrial reactive oxygen species scavenger, Mito-TEMPO. When combined with the anticancer drugs cisplatin or doxorubicin, 4-hydroxychalcone led to greater reductions in cell viability than was induced by either anti-cancer agent alone. In summary, this study identifies a cytotoxic effect of 4-hydroxychalcone in MYCN-amplified human neuroblastoma cells, which rationalizes its further study in the development of new therapies for pediatric neuroblastoma.


Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4138
Author(s):  
Yeon-Jin Cho ◽  
Sun-Hye Choi ◽  
Ra-Mi Lee ◽  
Han-Sung Cho ◽  
Hyewhon Rhim ◽  
...  

Gintonin is a kind of ginseng-derived glycolipoprotein that acts as an exogenous LPA receptor ligand. Gintonin has in vitro and in vivo neuroprotective effects; however, little is known about the cellular mechanisms underlying the neuroprotection. In the present study, we aimed to clarify how gintonin attenuates iodoacetic acid (IAA)-induced oxidative stress. The mouse hippocampal cell line HT22 was used. Gintonin treatment significantly attenuated IAA-induced reactive oxygen species (ROS) overproduction, ATP depletion, and cell death. However, treatment with Ki16425, an LPA1/3 receptor antagonist, suppressed the neuroprotective effects of gintonin. Gintonin elicited [Ca2⁺]i transients in HT22 cells. Gintonin-mediated [Ca2⁺]i transients through the LPA1 receptor-PLC-IP3 signaling pathway were coupled to increase both the expression and release of BDNF. The released BDNF activated the TrkB receptor. Induction of TrkB phosphorylation was further linked to Akt activation. Phosphorylated Akt reduced IAA-induced oxidative stress and increased cell survival. Our results indicate that gintonin attenuated IAA-induced oxidative stress in neuronal cells by activating the LPA1 receptor-BDNF-TrkB-Akt signaling pathway. One of the gintonin-mediated neuroprotective effects may be achieved via anti-oxidative stress in nervous systems.


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