Experimental Study On The Treatment Of Alpha 1 Antitrypsin On Guinea Pig Skin Photoaging Model

Background Skin photoaging is a kind of skin aging caused by a variety of external factors,mainly by UV irradiation.Skin photoaging is a common phenomenon,which can lead to a large number of problems in the exposed skin.It is said that skin photoaging is related to skin cancer directly or not.To establish the animal model of Guinea pig skin photoaging,we can exposed the skin of back in UV irradiation for some time.Alpha 1 antitrypsin is a kind of Serine protease inhibitor and it plays an important role in anti-inflammatory as an antiproteases.Objectives 1.To establish the animal model of Guinea pig skin photoaging.2.To observe the prevention and therapeutic effect of Alpha 1 antitrypsin on Guinea pig skin photoaging model.Methods 1. Twenty female guinea pigs were randomized to two groups: control group(10 guinea pigs,remove the hair on the back every day),model group(10 guinea pigs, expose the guinea pigs to 20 w UV-A and UV-B light for some time after topical treatment with 0.1% Methoxsalen Solution 1-2h.After 120 h of topical irradiation discontinuously, the animal model of Guinea pig skin photoaging is established.).Observe the skin of all the Guinea pigs everyday. Observe the histopathological changes of the skin of the Guinea pigs in the model group once a week.2. Sixty female guinea pigs were were randomized to two three groups: control group(6 guinea pigs,remove the hair on the back every day),model group(48 guinea pigs, expose the guinea pigs to 20 w UV-A and UV-B light for some time after topical treatment with 0.1% Methoxsalen Solution 1-2h.After 120 h of topical irradiation discontinuously, the animal model of Guinea pig skin photoaging is established.),Preventive treatment group(6 guinea pigs,treated the same as the model group and give an intraperitoneal injection of AAT 20 mg each one every 3 days.).Observe the skin of all the Guinea pigs everyday. Observe the histopathological changes of the skin of the Guinea pigs in the model group once a week.3. Forty-two guinea pigs of the model group were randomized to seven groups: high-dose treatment group by intraperitoneal injection(6 guinea pigs,give an intraperitoneal injection of AAT 20 mg each one every 3 days),low-dose treatment group by intraperitoneal injection(6 guinea pigs, give an intraperitoneal injection of AAT 5mg each one every 3 days),high-dose treatment group by topical application(6 guinea pigs, topical application with AAT 20 mg every 3 days),low-dose treatment group by topical application(6 guinea pigs, topical application with AAT 5mg every 3 days),positive control group(6 guinea pigs, topical application with Tretinoin ointment every day),negative control group 1(6 guinea pigs, give an intraperitoneal injection of sterile water 0.5ml each one every 3 days),negative control group 2(6 guinea pigs, topical application with gel 0.5ml every 3 days).Observe and compare the skin of all the Guinea pigs everyday(skin photoaging severity score). Observe and compare the histopathological changes of the skin of the Guinea pigs once a week(the thickness of epidermis).At last make the statistical analysis.Results 1.The animal model of Guinea pig skin photoaging is established after exposure to the light for 120 h discontinuously.The skin of the Guinea pigs show the topical changes of photoaging in apperance and histopathology。2.AAT is very effective in the prevention of skin photoaging(P<0.05);high-dose treatment by intraperitoneal injection AAT 、 high-dose treatment by topical application、low-dose treatment by topical application and topical application with Tretinoin ointment are very effctive in treating skin photoaging(P<0.05).Expecially, the effect of high-dose treatment by topical application is better than topical application with Tretinoin ointment(P<0.05); There is no difference between intraperitoneal injection AAT and topical application with AAT(P>0.05).Conclusions 1. Expose the guinea pigs to 20 w UV-A and UV-B light for some time after topical treatment with 0.1% Methoxsalen Solution 1-2h,After 120 h of topical irradiation discontinuously,the animal model of Guinea pig skin photoaging is established.2. alpha 1 anti trypsin on the skin of the guinea pig model has a certain role in prevention and treatment, and the efficacy of dose dependent. Intraperitoneal injection and local external use of these two kinds of drug delivery methods did not show significant difference.