Stellate Ganglion Nrf2 Modulates Oxidative Stress and Heart Rate Responses in Mice and Rats with Heart Failure

Figures

• 

  Figure 1. (A) Schematic representation of mouse myocardial infarction (MI) protocol. Six weeks post-MI (n = 29) or sham (n = 26) surgery, mice with chronic heart failure (CHF) had reduced ejection fraction (B) and fractional shortening (C). (D) Representative images for infarction size and echocardiography, left ventricle short-axis m-mode for sham and CHF mice. Red line denotes end diastolic diameter; green line denotes end systolic diameter. (E) Infarction size correlated with ejection fraction; male, R2 = 0.62, p < 0.0001. female, R2 = 0.64, p < 0.0001. Unpaired t-test **** p > 0.001.

• 

  Figure 2. (A) Representative Western blot for Nrf2 and NQO1 from sham and CHF mouse stellate ganglia (n = 12–13, all groups). (B) Group data presenting protein expression in relation to GAPDH in mice (n = 25). (C) Relationship between stellate ganglia Nrf2/GAPDH protein expression and ejection fraction in mice. (D) Relationship between stellate ganglia Nrf2 mRNA and ejection fraction in mice (n = 12, paired left and right stellate ganglia). (E) Representative Western blot for Nrf2 and NQO1 from sham and CHF rat stellate ganglia (n = 5, all groups). (F) Group data presenting protein expression in relation to GAPDH in rats. ** is p < 0.005, *** p < 0.001.

• 

  Figure 3. Representative images from the stellate ganglia of sham and CHF mice. PFA fixed and sliced sections of stellate ganglia from sham and CHF mice labeled with TH-tyrosine hydroxylase. (A) 3-Nitrotyrosine (3-NT), (B) 4-hydroxynonenal (4-HNE). (C) Fresh, whole mount imaging of stellate ganglia incubated with dihydroethidium (DHE). (D) DHE fluorescent intensity compared to ejection fraction in mouse stellates, green dots—sham mice, blue dots—myocardial infarction mice.

• 

  Figure 4. (A) Schematic of the MI rat, Nrf2 upregulation by viral transfection protocol. (B) Representative image showing Nrf2-GFP viral transfection in tyrosine hydroxylase-positive cells from the rat stellate ganglion. (C) Images from slices of rats stellate ganglion transfected with lenti-Nrf2-GFP and Nrf2 antibody. (D) Stellate ganglia without viral transfection and Nrf2 antibody labeling. Rats with MI show reduced ejection fraction (E) and fractional shortening (F) compared to sham. Stellate ganglia upregulation of Nrf2 had no effect on any echocardiography measures, including ejection fraction and fractional shortening 3 weeks after transfection.

• 

  Figure 5. Cardiac changes to right stellate ganglia stimulation. (A–C) Sham rats (Sham-GFP and Sham-Nrf2, n = 5, both groups). (A) changes in heart rate; (B) changes in dp/dt max; (C) changes in dp/dt min. (D–F) MI-GFP and MI-GFP Nrf2 rats. (D) changes in heart rate (MI-GFP and MI-Nrf2 both n = 6 both groups); (E) changes in dp/dt max; (F) changes in dp/dt min; (G) changes in heart rate after metoprolol treatment, (MI-GFP, n = 5; MI-Nrf2, n = 6), * p < 0.05, two-way ANOVA repeated measures—interaction and group.

• 

  Figure 6. Plasma NE before (A) and after (B) stellate stimulation in GFP and Nrf2 virally transfected rats. (n = 5–6, all groups) * p < 0.05.

• 

  Figure 7. Hemodynamic changes to intravenous dobutamine in anesthetized rats. (A) Sham; (B) rats with MI, (n = 5, all groups). two-way ANOVA-group: Sham-GFP–MI GFP.