Identification of Messenger RNA Signatures in Age-Dependent Renal Impairment

In general populations, age-dependent renal impairment contributes to the progression of renal dysfunction. It has not been known which molecules are involved in age-dependent renal im-pairment. Messenger RNA (mRNA) has been reported to modulate various renal diseases, and we therefore investigated mRNA signatures in age-dependent renal impairment. We performed an initial microarray-profiling analysis to screen mRNAs, the expression levels of which changed in the kidneys of 50-week-old senescence-accelerated prone (SAMP1) mice (which have accelerated age-dependentd renal impairments) compared with those of 50 -wk- old senes-cence-accelerated-resistant (SAMR1) mice (which have normal aged kidneys) and with younger (10 -wk- old) SAMP1 and SAMR1 mice. We next assessed the expressions of mRNAs that were differentially expressed in the kidneys of SAMP1-50wk mice by conducting a quantitative real-time polymerase chain reaction (qRT-PCR) and compared the expressions among the SAMP1-10wk, SAMR1-10wk, and SAMR1-50wk mice. The results of the microarray together with the qRT-PCR analysis revealed five mRNAs whose expression levels were significantly altered in SAMP1-50wk mouse kidneys versus the control mice. The expression levels of the five mRNAs’ expression levels were increased in the kidneys of the mice with age-dependent renal impairment. Our findings in-dicate that the five mRNAs might be related and could become therapeutic targets for age-dependent renal impairment. 10-week-old SAMR1 mice (n=2), 50-week-old SAMR1 mice (n=2), 10-week-old SAMP1 mice (n=2), 50-week-old SAMP1 mice (n=2)