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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

Tissue procurement for in vivo real-time reverse transcription polymerase chain reaction studies. An asterisk indicates the direction in which the Descemet’s membrane with the attached endothelium is stripped from the corneal stroma.
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f8-ijms-13-10970: Tissue procurement for in vivo real-time reverse transcription polymerase chain reaction studies. An asterisk indicates the direction in which the Descemet’s membrane with the attached endothelium is stripped from the corneal stroma.

Mentions: At the end of experiments, the animals were euthanized with CO2 gas. The excised rabbit corneas were then processed for quantitative real-time reverse transcription polymerase chain reaction (RT-PCR) analyses. Under a dissecting microscope (Leica, Wetzlar, Germany), the Descemet’s membrane with the attached endothelium was aseptically stripped from the corneal stroma and washed three times with PBS (Figure 8). For in vivo real-time RT-PCR, total RNA was isolated from corneal endothelium with TRIzol reagent according to the manufacturer’s procedure. Reverse transcription of the extracted RNA (1 μg) was performed using ImProm-II (Promega, Madison, WI, USA) and Oligo(dT)15 primers (Promega). The sequences of the primer pairs for each gene are listed in Table 2. Quantitative real-time RT-PCR was performed on a Light-Cycler instrument (Roche Diagnostics, Indianapolis, IN, USA) according to the manufacturer’s instructions with FastStart DNA Master SYBR Green I reagent (Roche Diagnostics). Each sample was determined in six replicates, and the gene expression results were normalized to the expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH).


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

Lai JY - Int J Mol Sci (2012)

Tissue procurement for in vivo real-time reverse transcription polymerase chain reaction studies. An asterisk indicates the direction in which the Descemet’s membrane with the attached endothelium is stripped from the corneal stroma.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

f8-ijms-13-10970: Tissue procurement for in vivo real-time reverse transcription polymerase chain reaction studies. An asterisk indicates the direction in which the Descemet’s membrane with the attached endothelium is stripped from the corneal stroma.
Mentions: At the end of experiments, the animals were euthanized with CO2 gas. The excised rabbit corneas were then processed for quantitative real-time reverse transcription polymerase chain reaction (RT-PCR) analyses. Under a dissecting microscope (Leica, Wetzlar, Germany), the Descemet’s membrane with the attached endothelium was aseptically stripped from the corneal stroma and washed three times with PBS (Figure 8). For in vivo real-time RT-PCR, total RNA was isolated from corneal endothelium with TRIzol reagent according to the manufacturer’s procedure. Reverse transcription of the extracted RNA (1 μg) was performed using ImProm-II (Promega, Madison, WI, USA) and Oligo(dT)15 primers (Promega). The sequences of the primer pairs for each gene are listed in Table 2. Quantitative real-time RT-PCR was performed on a Light-Cycler instrument (Roche Diagnostics, Indianapolis, IN, USA) according to the manufacturer’s instructions with FastStart DNA Master SYBR Green I reagent (Roche Diagnostics). Each sample was determined in six replicates, and the gene expression results were normalized to the expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH).

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