From: When the dust settles: what did we learn from the bexarotene discussion?
 |  |  | Experimental claims | |||||
---|---|---|---|---|---|---|---|---|
Research group | Drug formulation | Duration of treatment | Target engagement (ApoE/ABCA1) | Decrease of soluble Aβ | Clearance of deposited Aβ/plaques | Behavioral improvements | In vivo microglia activation | Mechanism-based toxicity |
Cramer et al. [4] | Bexarotene/Targretin in DMSO or micronized in water | 3 to 14 days and 3 months | Increase | Decrease of Aβ40 or Aβ42 >25% | Repeated dosing of 3 to 14 days decreases Aβ deposits by 30 to 75%; 3-month treatment had no effects | Improved context-dependent fear memory. Improved spatial memory. Improved social behavior | Unclear whether different from control | NR |
Price et al.[9] | Bexarotene in solutol:ethanol:water (15:10:75) | 3 to 7Â days | Increase | No effect | No effect | NR | NR | Increased liver weight |
Fitz et al. [11] | Targretin in glycerol | 15 days | Increase | Decrease of ISF Aβ40 and Aβ42 by 23 to 26%; no effect on extracted soluble Aβ | No effect | Improved spatial memory. Improved long-term memory | NR | NR |
Veeraraghavalu et al. [7] | Targretin in DMSO:ethanol:sunflower oil (6.6%:4%:89.6%) | 7Â days | Increase | Small effects | No effect | NR | No effect | NR |
Tesseur et al.[8] | Bexarotene in Captisol and HP-β-CD/Tween | 19 days | Increase | No effect | No effect | Unclear effect on social recognition memory and fear memory | NR. | Loss of body weight, irritation and breathing problems, increased grooming |
LaClair et al.[10] | Bexarotene in DMSO or corn oil | 3 to 14Â days | Increase | NR | No effect | No effect on context- or conditioned stimulus- dependent fear memory | No effect | NR |
Ulrich et al.[12] | Targretin in water | 36 hours | Increase | Decrease of ISF Aβ40 by 45% | NR | NR | NR | NR |