Objective To observe the effect of mild moxibustion on monocyte chemotaxis protein 1(MCP-1)/matrix metalloproteinase 2(MMP-2)/transforming growth factor β1(TGF-β1) pro-inflammatory signal loop in senile rats

so as to explore its mechanisms underlying improving vascular aging(VA). Methods Twenty-four male VA SD rats were randomized into senium(VA) control

medication and moxibustion groups

and other 8 young SD rats(aged 2 months) were used as the young control group. The VA model was established by intraperitoneal injection of D-galactose(300 mg·kg

(-1)

·d(-1)·d

(-1)

) once daily for 4 weeks

and verified by serum total testosterone(TT) and free testosterone(FT) levels. For rats of the moxibustion group

mild moxibustion was applied to bilateral “Shenshu”(BL23) and “Guanyuan”(CV4) for 20 min

once a day

5 days a week for 8 weeks. Rats of the medication group were treated by intraperitoneal injection of testosterone propionate(7 mg·kg(-1)) once daily for 4 weeks

and verified by serum total testosterone(TT) and free testosterone(FT) levels. For rats of the moxibustion group

mild moxibustion was applied to bilateral “Shenshu”(BL23) and “Guanyuan”(CV4) for 20 min

once a day

5 days a week for 8 weeks. Rats of the medication group were treated by intraperitoneal injection of testosterone propionate(7 mg·kg

(-1)

·[3 d](-1)·[3 d]

(-1)

) once daily for 8 weeks except weekends

and rats of the senium control and young control groups treated by intraperitoneal injection of the same dose of normal saline

once daily for 8 weeks except weekends. The duration of exhausted swimming(DES) before and after the treatment was recorded. H.E. staining and Masson staining were used to observe histopathological changes and collagen fiber content of the thoracic aortic tissue

respectively. The contents of serum TT

FT and angiotensin 2(Ang Ⅱ) were determined by ELISA. The immunoactivity of aortic MCP-1 was detected by immunohistochemistry

and the expression levels of aortic MCP-1

MMP-2 and TGF-β1 were detected by Western blot. Results Compared with the young control group

the levels of DES

serum TT and FT contents were significantly decreased(P

<

0.01)

while those of serum AngⅡ and collagen fiber contents

aortic MCP-1 immunoactivity and MMP-2

TGF-β1 and MCP-1 protein expression considerably increased in the senium control group(P

<

0.01). After the interventions

the decreased levels of DES

serum TT and FT contents and the increased levels of serum AngⅡ

collagen fiber contents

aortic MCP-1 immunoactivity and MMP-2

TGF-β1 and MCP-1 protein expression were reversed in both medication and moxibustion groups(P

<

0.01

P

<

0.05). The therapeutic effect of mild moxibustion was significantly superior to that of medication in down-regulating the aortic collagen fiber

serum AngⅡ contents and MCP-1 immunoactivity and protein expression(P

<

0.05). H.E. staining showed thickened endometrium and disordered arrangement of vascular smooth muscles of the aorta in the senium group

and thinner endometrium and regular and ordered arrangement of aortic vascular smooth muscles in both moxibustion and medication groups. Conclusion Mild moxibustion may improve vascular aging in senescence rats

which is possibly by suppressing vascular MCP-1/MMP-2/TGF-β1 pro-inflammatory signal loop.