Effect of NAD+ boosting on kidney ischemia-reperfusion injury
Fig 7
Effect of NAD+ boosting by NR on genes related to the de novo NAD+ pathway in the kidney.
The expression levels of genes related to the de novo biosynthesis pathway of NAD+ were examined. QPRT is a key enzyme in the NAD+ de novo pathway for converting Quinolinic acid to NAD+. It was significantly downregulated by IRI to the same extent in both the IRI+Vehicle and IRI+NR 24 hour groups. The levels became normalized or upregulated 14 days after IRI (A). The expression level of pgc-1α was also significantly downregulated after 24 hours in the IRI+vehicle and IRI+NR groups, as compared to the sham groups (B). (C) Cox4 was significantly downregulated in both IRI groups after 24 hours compared to the sham groups and became normal after 14 days (C). The two antioxidants Sod2 and Cat, downstream for pgc-1α, were significantly downregulated in both IRI groups after 24 hours compared with the sham groups. Finally, were also levels of Sod2 downregulated in the IRI+NR-14 days group compared to sham+NR (D and E). Qprt: Quinolinate Phosphoribosyltransferase; Pgc-1α: Peroxisome proliferator-activated receptor gamma coactivator 1α; Cox4: Cytochrome c oxidase subunit 4; Sod2: Superoxide dismutase 2; Cat: Catalase. Mean ± SD; * p < 0.05, ** p < .001, *** p < 0.0001.