Journal: Molecular Medicine Reports

Article Title: High-intensity exercise training inhibits excessive autophagy in the hyperlipidemic myocardium of ApoE -/- mice via the NAD + -mediated SIRT1/MFN2 pathway

doi: 10.3892/mmr.2025.13753

Figure Lengend Snippet: NAD + ameliorates cardiac damage in hyperlipidemic mice by modulating the SIRT1/MFN2 pathway. (A) Protein interaction analysis. (B) Expression levels of SIRT1 and MFN2 proteins in the heart tissues of mice. (C) Representative immunohistochemistry images showing the expression of SIRT1 and MFN2 in myocardial tissue. The arrows indicate areas of stained cells. Scale bar, 100 µm; magnification, ×40. (D) SIRT1 and MFN 2 were detected by immunofluorescence double staining to assess colocalization. Scale bars, 100 and 50 µm; magnification, ×40. Data are presented as the mean ± standard error of the mean (n=3); statistical analysis was performed using one-way ANOVA followed by Tukey's post hoc test. *P<0.05, **P<0.01, ***P<0.001. HFD, high-fat diet; MFN2, mitofusin 2; NAD + , nicotinamide adenine dinucleotide; ND, normal diet; SIRT1, sirtuin 1.

Article Snippet: To inhibit SIRT1 activity, cells were treated with 10 μM EX-527 (cat. no. HY-15452; MedChemExpress) for 24 h (37°C, 5% CO 2 ).

Techniques: Expressing, Immunohistochemistry, Staining, Immunofluorescence, Double Staining

Journal: Molecular Medicine Reports

Article Title: High-intensity exercise training inhibits excessive autophagy in the hyperlipidemic myocardium of ApoE -/- mice via the NAD + -mediated SIRT1/MFN2 pathway

doi: 10.3892/mmr.2025.13753

Figure Lengend Snippet: NAD + supplementation activates the PI3K/AKT/mTOR pathway in the myocardium. (A) TUNEL staining was performed to assess myocardial cell apoptosis in the heart tissues of mice. Magnification, ×40; scale bar, 100 µm. (B) Protein interaction analysis. Expression levels of (C) p-PI3K/PI3K, (D) p-AKT/AKT and (E) p-mTOR/mTOR in the heart tissues of mice. Data are presented as the mean ± standard error of the mean (n=4); statistical analysis was performed using one-way ANOVA followed by Tukey's post hoc test. *P<0.05, **P<0.01. HFD, high-fat diet; Mfn2, mitofusin 2; NAD + , nicotinamide adenine dinucleotide; ND, normal diet; p-, phosphorylated; Sirt1, sirtuin 1.

Article Snippet: To inhibit SIRT1 activity, cells were treated with 10 μM EX-527 (cat. no. HY-15452; MedChemExpress) for 24 h (37°C, 5% CO 2 ).

Techniques: TUNEL Assay, Staining, Expressing

Journal: Molecular Medicine Reports

Article Title: High-intensity exercise training inhibits excessive autophagy in the hyperlipidemic myocardium of ApoE -/- mice via the NAD + -mediated SIRT1/MFN2 pathway

doi: 10.3892/mmr.2025.13753

Figure Lengend Snippet: NAD + protects ApoE −/− HL-1 cells from lipid accumulation and oxidative stress. (A) Cell viability was significantly enhanced in the 5 mM NAD + group compared with that in the control group. (B) NAD + supplementation reduced TC levels in ApoE −/− -treated cells. (C) TG levels were also significantly decreased by NAD + treatment. (D) LDL-C levels were also reduced in the ApoE −/− + NAD + group, indicating improved lipid metabolism. (E) NAD + supplementation increased GSH levels, reflecting enhanced antioxidant defense. (F) SOD activity was also significantly elevated in the ApoE −/− + NAD + group, suggesting improved oxidative stress response. (G) ROS staining revealed reduced reactive oxygen species in the ApoE −/− + NAD + group, indicating a decrease in oxidative stress. Scale bar, 200 µm. (H) Microscopic images confirmed improved cell morphology and viability in the ApoE −/− + NAD + group. Scale bar, 100 µm. (I) JC-1 staining showed improved mitochondrial membrane potential in the ApoE −/− + NAD + group. Scale bar, 100 µm. (J) Immunofluorescence staining demonstrated increased expression of SIRT1 in the ApoE −/− + NAD + group, suggesting activation of the SIRT1 pathway. Magnification, ×40; scale bar, 50 µm. Data are presented as the mean ± standard error of the mean (n=3); statistical analysis was performed using one-way ANOVA followed by Tukey's post hoc test. *P<0.05, **P<0.01, ***P<0.001. ApoE −/− , apolipoprotein E-deficient; GSH, glutathione; LDL-C, low-density lipoprotein cholesterol; NAD + , nicotinamide adenine dinucleotide; ROS, reactive oxygen species; SIRT1, sirtuin 1; SOD, superoxide dismutase; TC, total cholesterol; TG, triglycerides.

Article Snippet: To inhibit SIRT1 activity, cells were treated with 10 μM EX-527 (cat. no. HY-15452; MedChemExpress) for 24 h (37°C, 5% CO 2 ).

Techniques: Control, Activity Assay, Staining, Membrane, Immunofluorescence, Expressing, Activation Assay

Journal: Molecular Medicine Reports

Article Title: High-intensity exercise training inhibits excessive autophagy in the hyperlipidemic myocardium of ApoE -/- mice via the NAD + -mediated SIRT1/MFN2 pathway

doi: 10.3892/mmr.2025.13753

Figure Lengend Snippet: NAD + enhances MFN2/SIRT1 expression and activates the PI3K/AKT pathway in HL-1 cells. (A) Representative immunofluorescence double staining showing colocalization of MFN2 and SIRT1 in HL-1 cells. Magnification, ×40; scale bars, 100 and 50 µm. Protein expression levels of (B) SIRT1 and MFN2, (C) PI3K and p-PI3K, (D) AKT and p-AKT, and (E) mTOR and p-mTOR in HL-1 cells. Data are presented as the mean ± SEM (n=4); statistical analysis was performed using one-way ANOVA followed by Tukey's post hoc test. *P<0.05, **P<0.01, ***P<0.001. ApoE −/− , apolipoprotein E-deficient; MFN2, mitofusin 2; NAD + , nicotinamide adenine dinucleotide; p-, phosphorylated; SIRT1, sirtuin 1.

Article Snippet: To inhibit SIRT1 activity, cells were treated with 10 μM EX-527 (cat. no. HY-15452; MedChemExpress) for 24 h (37°C, 5% CO 2 ).

Techniques: Expressing, Immunofluorescence, Double Staining

Journal: Molecular Medicine Reports

Article Title: High-intensity exercise training inhibits excessive autophagy in the hyperlipidemic myocardium of ApoE -/- mice via the NAD + -mediated SIRT1/MFN2 pathway

doi: 10.3892/mmr.2025.13753

Figure Lengend Snippet: Mechanistic overview of NAD + in improving HFD-induced cardiac dysfunction. High-intensity interval training elevates cardiac NAD + levels, and subsequent intraperitoneal NAD + supplementation further activates SIRT1/MFN2 signaling. This enhances PI3K/AKT/mTOR phosphorylation, promoting autophagy and mitochondrial quality control. Interventions also improve lipid metabolism, reducing TG, T-CHO, and LDL-C. Together, these mechanisms mitigate mitochondrial dysfunction, and metabolic disturbances in HFD-induced cardiac injury. LDL-C, low-density lipoprotein cholesterol; MFN2, mitofusin 2; NAD + , nicotinamide adenine dinucleotide; T-CHO, total cholesterol; TG, triglycerides; SIRT1, sirtuin 1.

Article Snippet: To inhibit SIRT1 activity, cells were treated with 10 μM EX-527 (cat. no. HY-15452; MedChemExpress) for 24 h (37°C, 5% CO 2 ).

Techniques: Phospho-proteomics, Control