Fig 2: Effects of knocking down of Nrf1 on TH expression in PVN of hypertensive rats. (A) Immunofluorescence for the expression of TH in PVN in different groups. (B) Changes of number of TH positive cells in PVN. *P < 0.05 vs. control animals (SHAM + scr or SHAM + shNrf1). #P < 0.05 2K1C + shNrf1 vs. 2K1C + scr.

Fig 3: SPD prevents age-associated depletion in myocardial polyamines and alterations of SIRT1/PGC-1α signaling pathway proteins. Representative immunoblot bands for ODC, SSAT, and p21 (A), and for SIRT1, PGC-1α, NRF1, NRF2, and TFAM (B) in myocardium from 3-, 6-, 12- and 24-month-old rats. GAPDH was used as loading control. (n = 10). * P < 0.05 vs. 3 months, ** P < 0.01 vs. 3 months. (C) Correlation between ODC and (a) SIRT1, (b) PGC-1α, (c) NRF1, (d) NRF2, and (e) TFAM in cardiac tissue from rats of different ages. (D) Correlation between SSAT and (a) SIRT1, (b) PGC-1α, (c) NRF1, (d) NRF2, and (e) TFAM in cardiac tissue from rats of different ages (n = 10). (E) Representative immunoblot bands for SIRT1, PGC-1α, NRF1, NRF2, and TFAM in the myocardium of young (3 months of age), old (24 months of age), and SPD-treated (6 weeks) old rats. (n = 4). # P < 0.05 vs. young, ## P < 0.01 vs. young, * P < 0.05 vs. old, ** P < 0.01 vs. old. (F, G) Expression of SIRT1, PGC-1α, NRF1, NRF2, and TFAM measured by western blot in NRMCs treated with 0, 2.5, 5, 10, or 20 μM SPD for 24 h (F) or 10 μM SPD for 0, 6, 12, 24, and 48 h (G). Quantification of protein expression is shown on the right-hand side of the graphs (n = 4). * P < 0.05 vs. control, ** P < 0.01 vs. control.

Fig 4: Effects of knocking down of Nrf1 on ROS in PVN of hypertensive rats. (A) DHE staining displaying superoxide anion production in the PVN; (B) Fluorescent intensity of DHE in PVN. *P < 0.05 vs. control animals (SHAM + scr or SHAM + shNrf1). #P < 0.05 2K1C + shNrf1 vs. 2K1C + scr.

Fig 5: Translation and transcription level of Nrf1 in PVN of hypertensive rats. (A) Expression of Nrf1 protein in PVN in different groups detected by Western blotting; (B) Group data for Nrf1 protein expression in PVN; (C) Group data for the mRNA expression of Nrf1 in PVN. *P < 0.05 vs. control animals (SHAM + scr or SHAM + shNrf1). #P < 0.05 2K1C + shNrf1 vs. 2K1C + scr.