Limits...
Biocompatibility of genipin and glutaraldehyde cross-linked chitosan materials in the anterior chamber of the eye.

Lai JY - Int J Mol Sci (2012)

Bottom Line: The interleukin-6 expressions at mRNA level were also detected by quantitative real-time reverse transcription polymerase chain reaction.As compared to the non-cross-linked counterparts, the GP-chi samples improved the preservation of corneal endothelial cell density and possessed better anti-inflammatory activities, indicating the benefit action of the GP cross-linker.In summary, the intracameral tissue response to the chemically modified chitosan materials strongly depends on the selection of cross-linking agents.

View Article: PubMed Central - PubMed

Affiliation: Institute of Biochemical and Biomedical Engineering, Chang Gung University, Taoyuan 33302, Taiwan; E-Mail: jylai@mail.cgu.edu.tw ; Tel.: +886-3-211-8800 (ext. 3598); ; Biomedical Engineering Research Center, Chang Gung University, Taoyuan 33302, Taiwan ; Molecular Medicine Research Center, Chang Gung University, Taoyuan 33302, Taiwan.

ABSTRACT
Chitosan is a naturally occurring cationic polysaccharide and has attracted much attention in the past decade as an important ophthalmic biomaterial. We recently demonstrated that the genipin (GP) cross-linked chitosan is compatible with human retinal pigment epithelial cells. The present work aims to further investigate the in vivo biocompatibility of GP-treated chitosan (GP-chi group) by adopting the anterior chamber of a rabbit eye model. The glutaraldehyde (GTA) cross-linked samples (GTA-chi group) were used for comparison. The 7-mm-diameter membrane implants made from either non-cross-linked chitosan or chemically modified materials with a cross-linking degree of around 80% were inserted in the ocular anterior chamber for 24 weeks and characterized by slit-lamp and specular microscopic examinations, intraocular pressure measurements, and corneal thickness measurements. The interleukin-6 expressions at mRNA level were also detected by quantitative real-time reverse transcription polymerase chain reaction. Results of clinical observations showed that the overall ocular scores in the GTA-chi groups were relatively high. In contrast, the rabbits bearing GP-chi implants in the anterior chamber of the eye exhibited no signs of ocular inflammation. As compared to the non-cross-linked counterparts, the GP-chi samples improved the preservation of corneal endothelial cell density and possessed better anti-inflammatory activities, indicating the benefit action of the GP cross-linker. In summary, the intracameral tissue response to the chemically modified chitosan materials strongly depends on the selection of cross-linking agents.

No MeSH data available.


Related in: MedlinePlus

Slit-lamp examination scores of rabbit eyes 24 weeks after surgical insertion of various chitosan implants in the ocular anterior chamber. The dash line represents the preoperative score. An asterisk indicates statistically significant differences (*p < 0.05; n = 6) as compared to the Ctrl (sham-operated) groups.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC3472724&req=5

f2-ijms-13-10970: Slit-lamp examination scores of rabbit eyes 24 weeks after surgical insertion of various chitosan implants in the ocular anterior chamber. The dash line represents the preoperative score. An asterisk indicates statistically significant differences (*p < 0.05; n = 6) as compared to the Ctrl (sham-operated) groups.

Mentions: The slit-lamp examination score for each group is shown in Figure 2. Before surgery, the overall ocular scores were relatively low, ranging from 0.2 to 0.5. In the Ctrl groups, the total scores were 0.7 ± 0.4, which indicates that the inflammation manifestations were not found in the sham-operated rabbits at 24 weeks post operation. After exposure to the Chi materials, the animals had a score of 2.5 ± 0.8, suggesting very little inflammation. Our data demonstrated that among all the test samples studied, the GTA-chi implants might induce severe inflammatory responses, leading to significantly higher scores. On the other hand, there were no significant differences between Ctrl and GP-chi groups (p > 0.05) with respect to aqueous flare, anterior chamber fibrin, corneal cloudiness, corneal neovascularization, iris neovascularization, and lens opacity measurements.


Biocompatibility of genipin and glutaraldehyde cross-linked chitosan materials in the anterior chamber of the eye.

Lai JY - Int J Mol Sci (2012)

Slit-lamp examination scores of rabbit eyes 24 weeks after surgical insertion of various chitosan implants in the ocular anterior chamber. The dash line represents the preoperative score. An asterisk indicates statistically significant differences (*p < 0.05; n = 6) as compared to the Ctrl (sham-operated) groups.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC3472724&req=5

f2-ijms-13-10970: Slit-lamp examination scores of rabbit eyes 24 weeks after surgical insertion of various chitosan implants in the ocular anterior chamber. The dash line represents the preoperative score. An asterisk indicates statistically significant differences (*p < 0.05; n = 6) as compared to the Ctrl (sham-operated) groups.
Mentions: The slit-lamp examination score for each group is shown in Figure 2. Before surgery, the overall ocular scores were relatively low, ranging from 0.2 to 0.5. In the Ctrl groups, the total scores were 0.7 ± 0.4, which indicates that the inflammation manifestations were not found in the sham-operated rabbits at 24 weeks post operation. After exposure to the Chi materials, the animals had a score of 2.5 ± 0.8, suggesting very little inflammation. Our data demonstrated that among all the test samples studied, the GTA-chi implants might induce severe inflammatory responses, leading to significantly higher scores. On the other hand, there were no significant differences between Ctrl and GP-chi groups (p > 0.05) with respect to aqueous flare, anterior chamber fibrin, corneal cloudiness, corneal neovascularization, iris neovascularization, and lens opacity measurements.

Bottom Line: The interleukin-6 expressions at mRNA level were also detected by quantitative real-time reverse transcription polymerase chain reaction.As compared to the non-cross-linked counterparts, the GP-chi samples improved the preservation of corneal endothelial cell density and possessed better anti-inflammatory activities, indicating the benefit action of the GP cross-linker.In summary, the intracameral tissue response to the chemically modified chitosan materials strongly depends on the selection of cross-linking agents.

View Article: PubMed Central - PubMed

Affiliation: Institute of Biochemical and Biomedical Engineering, Chang Gung University, Taoyuan 33302, Taiwan; E-Mail: jylai@mail.cgu.edu.tw ; Tel.: +886-3-211-8800 (ext. 3598); ; Biomedical Engineering Research Center, Chang Gung University, Taoyuan 33302, Taiwan ; Molecular Medicine Research Center, Chang Gung University, Taoyuan 33302, Taiwan.

ABSTRACT
Chitosan is a naturally occurring cationic polysaccharide and has attracted much attention in the past decade as an important ophthalmic biomaterial. We recently demonstrated that the genipin (GP) cross-linked chitosan is compatible with human retinal pigment epithelial cells. The present work aims to further investigate the in vivo biocompatibility of GP-treated chitosan (GP-chi group) by adopting the anterior chamber of a rabbit eye model. The glutaraldehyde (GTA) cross-linked samples (GTA-chi group) were used for comparison. The 7-mm-diameter membrane implants made from either non-cross-linked chitosan or chemically modified materials with a cross-linking degree of around 80% were inserted in the ocular anterior chamber for 24 weeks and characterized by slit-lamp and specular microscopic examinations, intraocular pressure measurements, and corneal thickness measurements. The interleukin-6 expressions at mRNA level were also detected by quantitative real-time reverse transcription polymerase chain reaction. Results of clinical observations showed that the overall ocular scores in the GTA-chi groups were relatively high. In contrast, the rabbits bearing GP-chi implants in the anterior chamber of the eye exhibited no signs of ocular inflammation. As compared to the non-cross-linked counterparts, the GP-chi samples improved the preservation of corneal endothelial cell density and possessed better anti-inflammatory activities, indicating the benefit action of the GP cross-linker. In summary, the intracameral tissue response to the chemically modified chitosan materials strongly depends on the selection of cross-linking agents.

No MeSH data available.


Related in: MedlinePlus