APP and Alzheimer disease: In a subsequent study, the group showed that chronic treatment (3-month IP injection) of HNG: (i) significantly improves spatial learning and memory deficits, (ii) reduces Aβ plaque accumulation and insoluble Aβ concentrations, and (iii) decreases neuro-inflammatory responses in middle-age APPswe/PS1dE9 mice, a double transgenic mouse model of AD over expressing APP, and mutant human PS-1 in neurons.