Objective

2

To observe the effects of moxibustion at "Feishu" (BL13) and "Xinshu" (BL15) on the circular RNA of exon 2-5 of the Pan3 gene (circPAN3)

forkhead box O3 (FOXO3)

and Bcl-2/adenovirus E1B19kDa-interacting protein 3 (BNIP3) in rats with chronic heart failure (CHF)

and explore the potential mechanisms of moxibustion in alleviating myocardial fibrosis.

Methods

2

Ten rats of 60 male SPF-grade SD rats were randomly assigned into a normal group. The remaining rats underwent left anterior descending coronary artery (LAD) ligation to establish the CHF model. Forty successfully modeled rats were randomly divided into a model group

a moxibustion group

a rapamycin (RAPA) group

and a moxibustion+RAPA group

with 10 rats in each group. The moxibustion group received mild moxibustion at bilateral "Feishu" (BL13) and "Xinshu" (BL15)

30 min per session. The RAPA group received intraperitoneal injection of the autophagy activator RAPA (1 mg/kg). The moxibustion+RAPA group first received RAPA injection

followed by mild moxibustion at bilateral "Feishu" (BL13) and "Xinshu" (BL15). All interventions were administered once daily for 4 consecutive weeks. After the intervention

cardiac ultrasound was used to measure ejection fraction (EF) and left ventricular fractional shortening (FS). Serum placental growth factor (PLGF) level was determined by ELISA. Myocardial tissue morphology and collagen volume were assessed using hematoxylin-eosin (HE) staining and Masson's trichrome staining. The expression levels of circPAN3

FOXO3

and BNIP3 mRNA in myocardial tissue were detected by real-time PCR

while FOXO3 and BNIP3 protein expression levels were analyzed by Western blot.

Results

2

Compared with the normal group

the model group exhibited myocardial cell disorder

severe fibrosis

and increased collagen volume (

P

<

0.01)

along with significantly decreased EF

FS

and c

ircPAN3 mRNA expression in myocardial tissue (

P

<

0.01)

and the serum PLGF level

as well as FOXO3 and BNIP3 mRNA and protein expression in myocardial tissue were increased (

P

<

0.01). Compared with the model group

the moxibustion group showed reduced myocardial fibrosis

decreased collagen volume (

P

<

0.01)

increased EF

FS

and circPAN3 mRNA expression in myocardial tissue (

P

<

0.01)

and decreased serum PLGF level as well as FOXO3 and BNIP3 mRNA and protein expression in myocardial tissue (

P

<

0.01). Compared with the model group

the RAPA group showed further deterioration in these parameters (

P

<

0.01). Compared with the RAPA group

the moxibustion+RAPA group exhibited alleviation of myocardial fibrosis

reduced collagen volume (

P

<

0.01)

increased EF

FS

and circPAN3 mRNA expression in myocardial tissue (

P

<

0.01)

and decreased serum PLGF level as well as FOXO3 and BNIP3 mRNA and protein expression in myocardial tissue (

P

<

0.01).

Conclusion

2

Moxibustion could alleviate myocardial fibrosis in CHF rats

possibly through upregulation of myocardial circPAN3 expression

downregulation of FOXO3 and BNIP3 expression

and inhibition of excessive myocardial autophagy.