【Animal modeling】-Effect of Tempol on NF-κB signaling pathway in myocardial hypertrophy rats

  Objective: To investigate the effect of 2, 2, 6, 6-tetramethyl-4-piperidinol (temPol) on NF-κB signaling pathway in rat cardiac hypertrophy?

  Methods: A rat model of myocardial hypertrophy was established by intraperitoneal injection of isoprenaline (ISO) (5 mg/kg, twice a day, for 2 weeks). Forty-two SD male rats were randomly divided into 3 groups. : normal control group, myocardial hypertrophy model group (ISO + normal saline group), tempol intervention group (ISO + tempol group)? After 8 weeks of corresponding drug intervention, the heart weight index (HWI) and left ventricular weight were measured left ventricular weight index (LVWI), HE staining was used to observe myocardial cell morphology and fibrosis, Masson staining was used to detect myocardial fibrosis in rats, and qRT-PCR was used to detect TNF-α?IL-6 mRNA levels in myocardial tissue respectively. The expression levels of IκBα?P-P65?P65 protein in rat myocardial tissue were determined by Western blot?

  Results: Compared with the normal control group, the HWI and LVWI of the model group were increased (P < 0.05), the transcription levels of TNF-α and IL-6 mRNA, the expression of P-P65/P65 were significantly increased, and the NF-κB inhibitory protein IκBα was significantly increased. The expression decreased (P < 0.05), the myocardial HE staining showed thickening of muscle fibers, the myocardial structure was disordered, the surface area of myocardial cells increased, the myocardial Masson staining showed increased myocardial fibrosis, and myocardial interstitial collagen fibers increased; compared with the model group, the HWI of the temPol group ?LVWI decreased (P < 0.05), the transcription level of TNF-α?IL-6 mRNA, the expression of P-P65/P65 were decreased to varying degrees, and the expression of IκBα was increased (P < 0.05). Myocardial structure disorder? The degree of myocardial cell hypertrophy is reduced, the degree of myocardial fibrosis is improved in myocardial Masson staining, and the interstitial collagen fibers are reduced?

  Conclusion: TemPol can improve ISO-induced myocardial hypertrophy, which may be closely related to inhibiting the activity of NF-κB signaling pathway?