Abstract: Background　Residents in the Qinghai-Tibet Plateau have long been exposed to the environment of high altitude，strong ultraviolet rays and anoxic dryness，so their incidence of photodamaged skin diseases，especially skin photoaging，is high.At the same time，however，Qinghai enjoys its particular vegetation resources because of its unique ecological environment.Therefore，this paper selects local plant，black Chinese wolfberry to study its anti-aging property.Objective　To investigate the protective effect of Qinghai Lycium ruthenicum procyanidin on mice skin aging model.Methods　The experiment was studied from October 2016 to December 2017.Fifty 45-day-old Kunming female mice were randomly divided into 5 groups，with 10 mice in each group.The five groups were Group A（normal group），Group B（skin aging model），Group C（skin aging model+Vitamin E drop），Group D（skin aging model+low-dose Lycium ruthenicum procyanidin） and Group E（skin aging model+high-dose Lycium ruthenicum procyanidin）．Mice in Group A were fed under normal light，and mice in Group B，C，D and E were injected with D-galactose subcutaneously combined with ultraviolet radiation A（UVA） and ultraviolet radiation B（UVB） exposure to establish a skin aging model.On the 11th day of modeling，mice in Group A and Group B were given 0.5 ml/d of 0.9% sodium chloride solution，mice in Group C given 0.5 ml/d of Vitamin E drops，and mice in Group D and Group E given 50 mg?kg-1?d-1 and 100 mg?kg-1?d-1 of Lycium ruthenicum procyanidin，respectively，for 30 days.On the 42nd day，the thickness of dermal layer，changes of collagen fibers and elastic fibers，the expression levels of matrix metalloproteinase-2（ MMP-2） mRNA and matrix metalloproteinase-9（MMP-9） mRNA were detected.Results　Under the light microscope（×40），the layer thickness of mice in Group B was significantly reduced compared with those in Group A，and the thickness of cortical layer of mice in Group C，D and E was slightly thicker than those in group B.Under the light microscope（×400），collagen fibers and elastic fibers of mice in Group B were missing with disordered arrangement and loosely，fractured and curled structure，compared with Group A.The mice in group C，with fractures and curls being still visible，showed more fibrous tissue with mesh arrangement than those in Group B.Compared with Group B and C，Group D and E showed obvious nascent fibrous tissue with neat arrangement and notably reduced fracture and curl.Moreover，the newly grown fiber of mice in Group E was more mature than those in Group D.The expression levels of MMP-2 mRNA and MMP-9 mRNA of mice in Group B were higher than those in Group A，Group D and E（P<0.05），while the expression levels of MMP-2 mRNA and MMP-9 mRNA of mice in group D were higher than those in Group E（P<0.05）．Conclusion　Lycium ruthenicum procyanidins has protective effect on mouse skin aging model and has potential application value of anti-skin aging.

Key words: Skin aging, Lycium barbarum, Proanthocyanidins, Collagen fibers, Elastic fibers

摘要： 背景　青藏高原地区居民长期处在高海拔、强紫外线和缺氧干燥的环境中，光损伤性皮肤病特别是皮肤光老化发病率高。青海地区因其独特的生态环境孕育着其特有的植被资源，本文选用当地植物青海黑果枸杞，对其抗衰老性进行研究。目的　探讨青海黑果枸杞原花青素对小鼠皮肤衰老模型的保护作用。方法　2016年10月—2017年12月，选取45日龄SPF级昆明种雌性小鼠50只，随机分为正常组（A组）、皮肤衰老模型组（B组）、皮肤衰老模型+维生素E滴剂组（C组）、皮肤衰老模型+低剂量黑果枸杞原花青素组（D组）、皮肤衰老模型+高剂量黑果枸杞原花青素组（E组），每组10只。A组小鼠正常光照饲养，B组、C组、D组、E组小鼠采用D-半乳糖皮下注射联合长波黑斑效应紫外线（UVA）、中波红斑效应紫外线（UVB）共同照射建立皮肤衰老模型。造模第11天，A组、B组小鼠给予0.9%氯化钠溶液灌胃0.5 ml/d，C组小鼠给予维生素E滴剂灌胃0.5 ml/d，D组、E组小鼠给予果枸杞原花青素灌胃，剂量分别为50 mg?kg-1?d-1和100 mg?kg-1?d-1，连续用药30 d。第42天检测各组小鼠皮肤真皮层厚度、胶原纤维、弹力纤维的改变及基质金属蛋白酶-2（MMP-2）mRNA、基质金属蛋白酶-9（MMP-9）mRNA表达水平。结果　光镜（×40）下，肉眼可见B组较A组真皮层厚度明显减小，C组、D组、E组较B组真皮层厚度稍增厚。光镜（×400）下，肉眼可见B组较A组真皮层胶原纤维及弹力纤维缺失、排列紊乱、结构松散，出现断裂、卷曲，C组较B组可见纤维组织增多、网状排列，仍可见断裂、卷曲，D组、E组较B组、C组明显可见新生纤维组织、排列整齐，断裂、卷曲明显减少，且E组较D组新生纤维更成熟。B组小鼠MMP-2 mRNA、MMP-9 mRNA表达水平高于A组、D组、E组 （P<0.05）；D组小鼠MMP-2 mRNA、MMP-9 mRNA表达水平高于E组（P<0.05）。结论　黑果枸杞原花青素对小鼠皮肤衰老模型具有保护作用，有潜在的抗皮肤衰老应用价值。

关键词: 皮肤衰老, 枸杞, 原花青素类, 胶原纤维, 弹力纤维