255:. These agents may show specific toxicity towards cancer cells because of the low level of antioxidant defenses found in tumors. Recent research demonstrates that redox dysregulation originating from metabolic alterations and dependence on mitogenic and survival signaling through reactive oxygen species represents a specific vulnerability of malignant cells that can be selectively targeted by pro-oxidant non-genotoxic redox chemotherapeutics.
214:
The relative importance of the antioxidant and pro-oxidant activities of antioxidant vitamins is an area of current research, but vitamin C, for example, appears to have a mostly antioxidant action in the body. However, less data is available for other dietary antioxidants, such as
93:
is associated with elevated tissue levels of copper. Such syndromes tend to be associated with common symptomology. Thus, all are occasional symptoms of (e.g) hemochromatosis, another name for which is "bronze diabetes". The pro-oxidant herbicide
265:
followed by exposing the target to appropriate wavelengths of light. The light excites the photosensitizer, causing it to generate reactive oxygen species, which can damage or destroy diseased or unwanted tissue.
65:. This greatly reduces the rates of these reactions, thus allowing aerobic life to exist. As a result, the reduction of oxygen typically involves either the initial formation of
45:
Some substances can serve as either antioxidants or pro-oxidants, depending on conditions. Some of the important conditions include the concentration of the chemical and if
73:
through a reduction of a transition-series metal such as manganese, iron, or copper. This reduced metal then transfers the single electron to molecular oxygen or peroxide.
137:
is also thought to be induced by the pro-oxidant properties of these agents. It may be that oxidative stress produced by such agents mimics a normal
446:
543:
Duarte TL, Lunec J (2005). "Review: When is an antioxidant not an antioxidant? A review of novel actions and reactions of vitamin C".
85:
is a classic "pro-oxidant" disease. Another disease associated with the chronic presence of a pro-oxidant transition-series metal is
410:
Jaeschke H, Gores GJ, Cederbaum AI, Hinson JA, Pessayre D, Lemasters JJ (2002). "Mechanisms of hepatotoxicity".
888:
749:
Hao Q, Maret W (2005). "Imbalance between pro-oxidant and pro-antioxidant functions of zinc in disease".
34:
systems. The oxidative stress produced by these chemicals can damage cells and tissues, for example, an
506:"Correlates of oxidative stress and free-radical activity in serum from asymptomatic shipyard welders"
207:
The metal ion in this reaction can be reduced, oxidized, and then re-reduced, in a process called
70:
27:
53:
are present. While thermodynamically very favored, reduction of molecular oxygen or peroxide to
261:
is used to treat some cancers as well as other conditions. It involves the administration of a
216:
883:
878:
505:
35:
479:
372:
258:
8:
893:
177:
90:
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or scar formation is another pro-oxidant-related symptom. E.g., interocular copper or
850:
801:
766:
731:
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58:
50:
23:
638:
Stohs SJ, Bagchi D (1995). "Oxidative mechanisms in the toxicity of metal ions".
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262:
138:
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316:"Inhibition of cellular antioxidants: a possible mechanism of toxic cell injury"
898:
521:
504:
Han SG, Kim Y, Kashon ML, Pack DL, Castranova V, Vallyathan V (December 2005).
290:
285:
114:
66:
62:
673:
Valko M, Morris H, Cronin MT (2005). "Metals, toxicity and oxidative stress".
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423:
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686:
607:
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244:
208:
146:
821:"Redox-directed cancer therapeutics: molecular mechanisms and opportunities"
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431:
396:
388:
173:
99:
836:
762:
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475:
357:
172:, however, it can also reduce metal ions which leads to the generation of
98:, Wilson's disease, and striatal iron have similarly been linked to human
275:
31:
339:
240:
142:
54:
239:
both bind to DNA and generate reactive oxygen species. These include
591:"Does vitamin C act as a pro-oxidant under physiological conditions?"
252:
248:
224:
161:
134:
122:
82:
331:
130:
118:
110:
95:
81:
Transition metals can serve as pro-oxidants. For example, chronic
710:"Dietary polyphenols: good, bad, or indifferent for your health?"
157:
102:. Paraquat also produces Parkinsonian-like symptoms in rodents.
46:
295:
165:
39:
409:
42:, partly through its production of reactive oxygen species.
220:
784:
Schneider C (2005). "Chemistry and biology of vitamin E".
447:"Prooxidant effects of antioxidant vitamins. Introduction"
89:, associated with elevated iron levels. Similarly,
36:
overdose of the analgesic paracetamol (acetaminophen)
125:is also a major symptom of Wilson's disease. The
672:
370:
870:
503:
203:2 Fe + Ascorbate → 2 Fe + Dehydroascorbate
160:that are reducing agents can be pro-oxidants.
117:chalicosis is associated with severe vitreous
313:
783:
707:
637:
542:
211:that can generate reactive oxygen species.
818:
844:
725:
606:
465:
444:
347:
748:
588:
371:James LP, Mayeux PR, Hinson JA (2003).
152:
871:
584:
582:
373:"Acetaminophen-induced hepatotoxicity"
16:Chemical that induces oxidative stress
579:
13:
230:
121:, as is interocular iron. Liver
14:
910:
164:has antioxidant activity when it
757:(2): 161–70, discussion 209–15.
812:
777:
742:
727:10.1016/j.cardiores.2006.10.004
701:
666:
631:
589:Carr A, Frei B (1 June 1999).
536:
497:
438:
403:
364:
307:
1:
510:Am. J. Respir. Crit. Care Med
314:Puglia CD, Powell SR (1984).
301:
168:oxidizing substances such as
819:Wondrak GT (December 2009).
652:10.1016/0891-5849(94)00159-H
467:10.1093/jn/126.suppl_4.1197S
7:
269:
105:
10:
915:
522:10.1164/rccm.200409-1222OC
22:are chemicals that induce
557:10.1080/10715760500104025
76:
687:10.2174/0929867053764635
608:10.1096/fasebj.13.9.1007
320:Environ. Health Perspect
133:and the antitumor agent
460:(4 Suppl): 1197S–200S.
424:10.1093/toxsci/65.2.166
217:polyphenol antioxidants
38:can fatally damage the
28:reactive oxygen species
26:, either by generating
825:Antioxid. Redox Signal
798:10.1002/mnfr.200400049
389:10.1124/dmd.31.12.1499
837:10.1089/ARS.2009.2541
763:10.3233/jad-2005-8209
640:Free Radic. Biol. Med
708:Halliwell B (2007).
259:Photodynamic therapy
153:Pro-oxidant vitamins
139:physiological signal
71:spin–orbit coupling
889:Chemical pathology
445:Herbert V (1996).
377:Drug Metab. Dispos
235:Several important
127:pulmonary fibrosis
786:Mol Nutr Food Res
751:J. Alzheimers Dis
237:anticancer agents
170:hydrogen peroxide
51:transition metals
30:or by inhibiting
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681:(10): 1161–208.
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478:. Archived from
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383:(12): 1499–506.
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91:Wilson's disease
61:respectively is
59:hydroxyl radical
24:oxidative stress
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831:(12): 3013–69.
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714:Cardiovasc. Res
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675:Curr. Med. Chem
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545:Free Radic. Res
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485:on 6 April 2008
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332:10.2307/3429932
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281:Oxidizing agent
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263:photosensitizer
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231:Use in medicine
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178:Fenton reaction
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87:hemochromatosis
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12:
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5:
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601:(9): 1007–24.
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516:(12): 1541–8.
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437:
402:
363:
305:
303:
300:
299:
298:
293:
291:Methylene blue
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286:Reducing agent
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245:anthracyclines
232:
229:
205:
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187:
154:
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147:myofibroblasts
145:conversion to
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78:
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67:singlet oxygen
63:spin forbidden
15:
9:
6:
4:
3:
2:
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646:(2): 321–36.
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551:(7): 671–86.
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418:(2): 166–76.
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209:redox cycling
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194:→ 2 Fe + 2 OH
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174:free radicals
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884:Cell biology
879:Antioxidants
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720:(2): 341–7.
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487:. Retrieved
480:the original
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412:Toxicol. Sci
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323:
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309:
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234:
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195:
176:through the
156:
129:produced by
109:
100:Parkinsonism
80:
44:
20:Pro-oxidants
19:
18:
792:(1): 7–30.
276:Antioxidant
32:antioxidant
894:Physiology
873:Categories
326:: 307–11.
302:References
243:and other
241:adriamycin
186:2 Fe + 2 H
143:fibroblast
55:superoxide
253:cisplatin
249:bleomycin
225:vitamin E
162:Vitamin C
135:bleomycin
123:cirrhosis
83:manganism
855:19496700
806:15580660
771:16308485
736:17141749
695:15892631
625:15426564
617:10336883
573:39962659
565:16036346
530:16166614
432:11812920
397:14625346
270:See also
158:Vitamins
131:paraquat
119:fibrosis
115:vitreous
111:Fibrosis
106:Fibrosis
96:paraquat
846:2824519
660:7744317
595:FASEB J
476:8642456
454:J. Nutr
358:6094175
349:1568295
340:3429932
166:reduces
853:
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571:
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474:
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346:
338:
251:, and
223:, and
198:+ 2 OH
77:Metals
47:oxygen
899:Redox
621:S2CID
569:S2CID
489:7 May
483:(PDF)
450:(PDF)
336:JSTOR
296:DCPIP
69:, or
40:liver
851:PMID
802:PMID
767:PMID
732:PMID
691:PMID
656:PMID
613:PMID
561:PMID
526:PMID
491:2007
472:PMID
428:PMID
393:PMID
354:PMID
221:zinc
141:for
841:PMC
833:doi
794:doi
759:doi
722:doi
683:doi
648:doi
603:doi
553:doi
518:doi
514:172
462:doi
458:126
420:doi
385:doi
344:PMC
328:doi
247:,
57:or
49:or
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.