In this study, aged plaque-bearing mice were fed doxycycline to repress TgAPP expression, implying a corresponding decrease in newly synthesized Aβ.
APP23 mice have been reported to develop plaques beginning at 6 8 months of age, and plaque development is faster in females than in males (Sturchler-Pierrat et al, 1997; Eisele et al, 2010).
Proteomics analysis was performed on hippocampal synaptosome fractions at 1.5 and 3 months of age, before plaque deposition, and at 6 and 12 months of age, after the onset of plaque formation (Additional file 2: Figure S1).
In addition, our results indicate that the rate of reduction in salivary flow during the follow-up period increased as age and plaque score increased.
In a multivariate linear regression model, age and plaque score remained independently associated with the increased rate of reduced salivary flow.
The first group ranged from 3 to 4 months, an age when plaque growth is still very dynamic in this mouse model [ 22].
A highly significant positive correlation was found between age and plaque index (p = 0.0018) with a significant correlation with gingival index and probing depth (Table 3).
Even in the multivariate linear regression model (Table 3), age and plaque score remained independently and positively associated with rate of reduction in salivary flow (age per decade, β = 0.058, P < 0.001; plaque score, β = 0.065, P = 0.012).
This population-based 5-year cohort study demonstrated that higher age and plaque score and lower serum albumin levels were significantly associated with increased risk of obviously reduced salivary flow rate during the follow-up period.
In a multivariate logistic regression model, higher age and plaque score and lower serum albumin levels were significantly associated with greater odds of an obvious reduction in salivary flow rate (age per decade, odds ratio [OR] = 1.25, 95% confidence interval [CI] = 1.03 1.51; serum albumin levels <4 g/dL, OR = 1.60, 95% CI = 1.04 2.46; plaque score ≥1, OR = 1.53, 95% CI = 1.04 2.24).
