Research Article
Tea Polyphenol Attenuates Oxidative Stress-Induced Degeneration of Intervertebral Discs by Regulating the Keap1/Nrf2/ARE Pathway
| | Morphology change under optical microscope | Grade |
| I | Annulus fibrosus (AF) | Normal texture and free of damage and distortion | 1 | The damaged and distortion area is less than 30% | 2 | The damaged and distortion area is more than 30% | 3 |
| II | Boundary between AF and NP | Normal | 1 | Micro disrupted | 2 | Medium or severe disrupted | 3 |
| III | NP cells | Normal cells with large amounts of vacuoles | 1 | Cells and vacuoles decreased slightly | 2 | Cells decreased moderately or severely without vacuoles | 3 |
| IV | NP matrix | Normal gel appearance | 1 | Slightly congealed | 2 | Moderate or severe condensation | 3 |
|
|