Oxidative Medicine and Cellular Longevity

Review Article

The Role of Thyroid Hormones as Inductors of Oxidative Stress and Neurodegeneration

Table 1

Effects of hyper- or hypothyroidism on the activity/abundance of antioxidant enzymes and the oxidative status of various tissues.
 HyperthyroidismHypothyroidism
TissueSODGPxCATGSHLpxChlCrbSpeciesSODGPxCATGSHLpxChlCrbSpecies
Heart↑↓↓ ↑  Rat [18]↓   —  Rat [18]
↑↑—↓↑↑↑Rat [48]↓↓↓ ↓ ↓Rat [41]
 —  ↑  Rat [39] ↑  —  Rat [39]
   ↑↑  Rat [49]   ↓↓  Rat [49]
     ↑ Rat [50]——— —  Rat young [42]
↑—— —  Rat young [42]——— —  Rat old [42]
—↓— ↑  Rat old [42]        
Liver    ↓  Mouse [51]    —  Mouse [51]
—↓↓ —  Rat [18]—   —  Rat [18]
↓ ↓  ↑ Rat [40]—↑— —  Rat [52]
↑↑↑ ↑↑  Rat [52]    ↓ ↓ ↓Rat [53]
    ↓ ↓ ↓Rat [53] —  —  Rat [39]
 ↑    ↑Rat [54]   ↓↓  Rat [49]
 —  ↑  Rat [39]        
   ↑↑  Rat [49]        
↓↓ ↓↑ ↑Rat [55]        
     ↑ Rat [50]        
↓↓↓↓   Rat [56]        
    ↑ ↑Rat [57]        
 ↑ ↓↑  Rat [58]        
Microsomes     ↑  Rat [32]        
Mitochondria       ↑Rat [54]        
Skeletal muscle    ↑  Mouse [35]↓—  ↑  Duck [59]
 ↑  ↑  Rat [39]    —  Mouse [35]
         ↑  —  Rat [39]
Oxidative ↑↓↓ ↑  Rat [18]↓—— —  Rat [18]
Glycolytic         ↓—— —  Rat [18]
Blood                
Plasma     ↑  Rat [60]↓   ↑  Rat [61]
     ↑ Rat [50]↓↑—↓↑  Human [62]
 — ↑↑  Rat [63]— ↑ ↑  Human [64]
    ↑  Human [65]    ↑  Human [66]
    ↑  Human [67]↑ ↑ ↑  Human [68]
    ↑  Human [69]    —  Human [70]
    ↑  Human [71] ↑—↓↑↑ ↑Human [72]
↓   ↑  Human [73]    ↑ ↑Human [74]
↑↓↑ ↑  Human [75]    ↑ ↑Human [76]
    ↑  Human [66]↓↓↓    Human [77]
    ↑  Human [78]    ↑  Human [78]
Erythrocytes — — ↑ ↑Rat [79]— — ↓ ↓Rat [79]
↑  ↓↑  Rat [80]        
↑↓— —  Rat [18]        
   —   Cat [81]        
↑↑  —  Human [73]       
Brain                
Homogenate    ↑↑  Rat [49]   ↓↓  Rat [49]
↑↑↑  ↑↑ Rat juvenile [27]↑ ↑↓↑ ↑Rat neonate [82]
↓↓↑ ↑  Rat neonate [83]↓ ↓↓↓ ↑  Rat neonate [83]
Mitochondria —↓  ↑ ↑↑Rat [19]↑↑  ↑ ↑Rat [19]
Cortex     ↑↑  Rat [19]    —  Rat [19]
↑   ↑  Rat [84]—   —  Rat [85]
—↑↑ —  Rat old [86]↓↑↓ ↓  Rat neonate [87]
        ↑↑— ↑  Rat old [86]
Hippocampus         ↓   ↑  Rat [61]
            ↑  Rat [88]
           ↓↑  Rat neonate [89]
Cerebellum ↓   —  Rat [84]↓   ↑  Rat [85]
            —  Rat [88]
↓ ↓↓↓ ↑  Rat neonate [83]↓—↑ ↓  Rat juvenile [90]
        ↑—— ↑  Rat neonate [90]
        ↓ ↓↓↓ ↑  Rat neonate [83]
Medulla ↓ ↓↓↓ ↑  Rat neonate [83]↓ ↓↓↓ ↑  Rat neonate [83]
Antioxidant enzymes and substrates: SOD: superoxide dismutase (no distinction is made between Cu/Zn-SOD and Mn-SOD); GPx: glutathione peroxidase; CAT: catalase; GSH: reduced glutathione.
Oxidative status: Lpx: lipid peroxidation (measured as thiobarbituric acid-reactive substances: TBARS or malondialdehyde production); Chl: chemiluminescence; Crb: carbonylated proteins.
↓: decrease; ↑: increase; —: no change. Double arrows represent a highly significant effect ( ).