碩士 / 靜宜大學 / 食品營養學系 / 99 / The increase of oxidantive stress with aging has been proposed to be the contributor to the age-related hearing imparment. Over accumulation of reactive oxygen species (ROS) in inner ear was suspected to acclerate the atrophy of hair cells and spiral ganglion cells, and induce cell apoptosis. The supplementation of antioxidants has been proved to reduce the oxidantive stress, and slow the aging process. Spirulina platensis showed good antioxidant capacity, anti-inflammation and neuroprotective effect. Thus, this study was aimed to examine the effects of Spirulina platensis on age-related hearing imparment and related mechanism in senescence accelerated mice (SAM). Eleven-month- old SAM mice were randomly divided into three experimental groups, including SAMR1 control, SAMP8 control, and Spirulina platensis (400 mg/Kg BW) SAMP8 groups. The ABR test were performed at the pre- and post six feeding weeks. After sacrificed, lipid peroxidase, antioxidant enzymes, B-cell leukemia/lymphoma 2 (Bcl-2), Bcl-2 associated X protein (Bax), 5-hydroxytryptamine 2B recrptor (5-HT2B receptor), tumor necrosis factor-α(TNF-α) mRNA expsression of brainstem, temporal lobe and inner ear were examined, and the percentage of caspase-3 in cochlea was caculated. The results shows that the Spirulina platensis could improve the ABR threshold and hearing degeneration in SAMP8 mice, and reduce the interval of cochlear nerve to cochlear nucleus at high frequency level. The malondiadehyde(MDA) concentration of brain stem and inner ear were lower in Spirulina platensis diet gruop, whereas the difference did not find in the temporal lobe. Spirulina platensis could increase the superoxiede dismutase (SOD), catalase (CAT) mRNA expression in the brain stem, temporal lobe and inner ear, and also enhanced the glutathione peroxidase (GPx) mRNA expression in temporal lobe and inner ear, whereas the GPx mRNA expression did not differ in the brain stem. The administration of Spirulina platensis increased the Bcl-2 mRNA expression in brain stem, and decreased the Bax mRNA expression in temporal lobe and inner ear. However, there were not significant differences on the caspase-3 percentage in cochlea, 5-HT2B receptor and TNF-α mRNA expression in the brain stem, temporal lobe, and inner ear among three groups. In summary, we concluded that Spirulina platensis could improve the age-related hearing imparment in SAMP8 mice. The mechanism might relate to promote the antioxidantive defense system and reduce the over-expression of apoptosis.
| Identifer | oai:union.ndltd.org:TW/099PU000255028 |
| Date | January 2011 |
| Creators | Hsin-Yi Cheng, 鄭欣宜 |
| Contributors | Yin-Ching Chan, 詹吟菁 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 97 |
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