Table 2.

Blood-based biomarkers.

Biomarker	Method of measurement
Vitamin D	ELISAa
Lutein zeaxanthin	ELISA
Troponin T	ELISA
Pro-brain natriuretic peptide	ELISA
Soluble receptor for advanced glycation end products	ELISA
MicroRNA 125	qRT-PCRb
MicroRNA 194	qRT-PCR
MicroRNA 454	qRT-PCR
Interleukin-6	ELISA and Luminex
P16INK4A	qRT-PCR
P21CIP	qRT-PCR
New unpublished	qRT-PCR and ELISA

^aELISA: enzyme-linked immunosorbent assay.

^bqRT-PCR: real-time quantitative reverse transcription polymerase chain reaction.