Study Of The Stability,Conjunctival Irritation And Influence Of IL-6Expression Of Cyclosporine A Ophthalmic Preparations

ObjectiveCyclosporine A is isolated from the broth of Tolypocladium inflatum. It is an immunosuppressant. It has anti-inflammatory effects. When treating patients with keratoconjunctivitis sicca whose eyes inflammation caused by tear secretion inhibition, cyclosporine A ophthalmic preparation could help increasing tear secretion in patients as a local regulator. We do formulation screening studys to find a premium formulation with good performance at stability, less irritant and anti-inflammatory effect by preparing different formulations of cyclosporine A.Methods1. Preparation samples by selecting different combinations of emulsifier (Tween80, Cremophor EL, Solutol HS15).2. Investigate the stability of each prescription through stability test. Meanwhile investigate the irritant of each.3. Making dry eye model through removing the lacrimal gland and harderian gland of each rabbit’s left eye by surgical. Postoperative examine the rabbit with corneal and conjunctival rose bengal staining, tear film breakup time and Schirmer Ⅱ test. After14days, according to the diagnostic criteria the rabbits are diagnosed with dry eye.4. The rabbits were randomly divided into four groups,3treatment groups each given one prescription, while the control group received a blank agent. Twice a day,100μL (2drops) of emulsion were applied to the rabbits’ right eye for21days. Then examinate the rabbits with rose bengal staining, tear film breakup time and Schirmer II test.5. In the condition of minimize human factors, four groups rabbits’ tear were taken on the days of14,21,28,35, and detected the content of IL-6by radioimmunoassay.6. The statistical analysis was described by SPSS23.0software. There is no significant statistical difference (P>0.05). There is statistical difference (P<0.05) and significant difference (P<0.01). Results1. The cyclosporine A formulation emulsified by Solutol HS15is stable and mild.2. The tests of stability and conjunctival irritation show the stability and conjunctival irritation of cyclosporine A formulations emulsified by solutol HS15is similar to Cremophor EL, both are better than tween80.3. Postoperative there is significant statistical difference in the results of3tests vs preoperative (P<0.01).14days after surgery, according to the diagnostic criteria the rabbits are diagnosed with dry eye.4. After21days treatment, observed indicators which showing3treatment groups’ wet length of Schirmer filter paper increased a lot more, tear film breakup time is extremely longer and the score of corneal and conjunctival rose bengal staining is much lower than the control group. There is a significant difference in the results (P<0.01). The results of3tests show that treatment group2&3’s effect are similar, both are better than treatment group1. There is statistical difference (P<0.05). Treatment group3is a little bit better than group2. There is no significant statistical difference (P>0.05).5. Detect the IL-6levels in tears on the days of7,14,21and28the control group’s level is much higher than the treatment groups’(P<0.01). Treatment group l’s IL-6level in tears is higher than treatment group2&3(P<0.05). Treatment group2’s IL-6level in tears is slightly higher than treatment group3(P>0.05).Conclusion1. Avoiding the use of Tween80as emulsifier can reduce the risk of stimulation of the conjunctiva.2.3kinds of prescriptions can effectively reduce the IL-6levels in tear of dry eye rabbits and relieve symptoms. Prescription2and3are better than prescription1, prescription.3. Solutol HS15can help to get a better efficacy of cyclosporine A and effectively reduce the adverse reactions.