ABSTRACT
Objective::To investigate the protective effect of Ginseng Radix et Rhizoma, Notoginseng Radix et Rhizoma and Chuanxiong Rhizoma extracts on vascular calcification induced by high glucose in mice by observing the expression of osteopontin (OPN) and smooth muscle 22α (SM22α) as well as vascular calcium deposition in the common carotid artery and thoracic aorta of mice. Method::Totally 130 male C57BL/6 mice were randomly divided into normal control group and high glucose group. The mice in high glucose group were intraperitoneally injected with streptozotocin(STZ), and fed on a high-fat diet for 7 months. Then, the mice were randomly divided into model group, low-dose and high-dose Ginseng Radix et Rhizoma, Notoginseng Radix et Rhizoma and Chuanxiong Rhizoma extracts groups (0.819, 1.638 g·kg-1), and metformin group (150 mg·kg-1). Each group was intragastrically administered once a day for 9 weeks. The changes in blood glucose were measured. Seven days before the end of the administration, a group of 4-week old male C57BL/6 mice were purchased and fed normally for one week as a youth group. At the end of the administration, the common carotid artery and thoracic aorta tissues of the mice were collected. Von Kossa staining was used to determine the degree of calcium deposition in the common carotid artery and thoracic aorta. The expression levels of OPN and SM22α protein in the common carotid artery and thoracic aorta were detected by immunohistochemistry. The expression of OPN and SM22α protein in the common carotid artery of mice was determined by Western blot. Result::As compared with the young group, the blood glucose of the normal control group was slightly increased without statistical difference, the common carotid artery and thoracic aorta were uniformly stained, and no black granular precipitate was observed. As compared with the normal control group, the blood glucose of the model group was increased (P<0.01), with a large amount of brown-black particles deposited in the intimal elastic fibers, showing obvious calcium salt deposition. As compared with the model group, blood glucose was significantly decreased in each administration group (P<0.05, P<0.01), and the degree of vascular calcium salt deposition was significantly reduced. There were no significant changes in expression levels of OPN protein and SM22α protein in the common carotid artery and thoracic aorta between the youth group and normal control group. As compared with the normal control group, the expression of intimal OPN protein in the common carotid artery and thoracic aorta of the model group was positive, SM22α protein expression was weakly positive, and the gray value of OPN protein expression in the common carotid artery was significantly increased (P<0.01), while the gray value of SM22α protein was decreased significantly (P<0.01). As compared with the model group, the expression levels of intimal OPN protein and SM22α protein in the common carotid artery and thoracic aorta of each administration group were significantly improved, and the gray value of OPN protein expression in the common carotid artery was reduced (P<0.05, P<0.01), while SM22α protein expression was significantly increased (P<0.01). Conclusion::High glucose can induce calcification of common carotid artery and thoracic aorta in mice and accelerate vascular aging. This formation process may be related to the expression of OPN and SM22α. Ginseng Radix et Rhizoma, Notoginseng Radix et Rhizoma and Chuanxiong Rhizoma extracts can reduce vascular calcification and delay vascular aging by regulating the expression of OPN and SM22α.