TABLE 1.
Carotenoid effects on diabetic complications1
| Carotenoid | Complication | Model | Dose | Duration | Outcome | Reference |
| Lutein and zeaxanthin | DR | Human/case control | 6 mg lutein/d | 3 mo | ↑Serum lutein/zeaxanthin | (70) |
| 0.5 mg zeaxanthin/d | ↑Visual acuity | |||||
| ↓Foveal thickness | ||||||
| Lutein | DR | Diabetic mice | 0.1% | 1 and 4 mo | ↓ROS generation in retina | (69) |
| ↓Visual impairment | ||||||
| ↓ERK activation | ||||||
| Lutein | DR | Diabetic mice | 0.2 mg/(kg · d) | 10 d | ↓Plasma/retina MDA | (68) |
| ↓NFκB activity | ||||||
| ↑GSH/GPx activity | ||||||
| Zeaxanthin | DR | Diabetic rats | 0.02% and 0.1% | 8 wk | ↓NFκB activity | (42) |
| ↑GSH/GPx activity | ||||||
| ↓VEGF | ||||||
| ↓ICAM-1 | ||||||
| ↑Mitochondrial SOD | ||||||
| ↓Lipid peroxidation | ||||||
| Lycopene | DN | Diabetic rats | 20 mg/(kg · d) | 8 wk | ↓Blood urea nitrogen | (78) |
| ↓24-h urea protein | ||||||
| ↓24-h creatinine | ||||||
| ↑AKT/PKB phosphorylation | ||||||
| ↓MDA and CTFG expression | ||||||
| ↑SOD activity | ||||||
| Lycopene | DN | Diabetic mice | 40 and 80 mg/(kg · d) | 8 wk | ↓NFκB/TNF-α | (77) |
| ↓LDL-C, | ||||||
| ↑HDL-C | ||||||
| ↓Blood glucose | ||||||
| ↑SOD | ||||||
| ↑GPx | ||||||
| ↑MDA | ||||||
| Lycopene | DPN | Diabetic mice | 1.2 and 4 mg/kg | 4 wk | ↓TNF-α/NO release | (26) |
| ↓Thermal hyperalgesia | ||||||
| Astaxanthin | DN | Diabetic db/db mice | 0.02% | 12 wk | ↓Blood glucose | (14) |
| ↓Urinary albumin | ||||||
| ↓Renal/mesangial 8-OHdG | ||||||
| ↓Relative mesangial | ||||||
| Astaxanthin | DN | Diabetic rats | — | 21 d | ↑Antioxidant enzymes activity (catalase, SOD) | (15) |
| ↓Plasma/kidney MDA | ||||||
| ↓Plasma/kidney PCO | ||||||
| Astaxanthin | DN | Epithelial cells | 5 and 10 μg/mL | — | ↓Lipid peroxidation | (16) |
| ↓Total reactive species | ||||||
| ↓iNOS/COX-2 protein concentrations | ||||||
| ↓NF-κB nuclear translocation | ||||||
| ↓Apoptosis | ||||||
| Astaxanthin | DR | Diabetic db/db mice | 25 and 50 mg/(kg · d) | 8 wk | ↓Apoptosis of RGCs | (19) |
| ↓MDA, | ||||||
| ↓8-OHdG | ||||||
| ↑MnSOD | ||||||
| ↓H2O2-induced apoptosis in RGC-5 |
1
AKT/PKB, protein kinase B; COX-2, cyclooxygenase 2; CTFG, connective tissue growth factor; DN, diabetic nephropathy; DPN, diabetic peripheral neuropathy; DR, diabetic retinopathy; ERK, extracellular signal-regulated kinase; GSH/GPx, glutathione/glutathione peroxidase; ICAM-1, intercellular adhesion molecule 1; iNOS, inducible NO synthase; MDA, malondialdehyde; MnSOD, manganese superoxide dismutase; PCO, protein carbonyl; RGC, retinal ganglion cell; ROS, reactive oxygen species; SOD, superoxide dismutase; VEGF: vascular endothelial growth factor; 8-OHdG, 8-hydroxy-2-deoxyguanosine; ↑, increase; ↓, decrease.