Limits...
An electro-responsive hydrogel for intravascular applications: an in vitro and in vivo evaluation.

Verbrugghe P, Verhoeven J, Coudyzer W, Verbeken E, Dubruel P, Mendes E, Stam F, Meuris B, Herijgers P - J Mater Sci Mater Med (2015)

Bottom Line: Minimal invasive implantation in the carotid artery of sheep was used to evaluate its medium-term biological effects, through biochemical, macroscopic, radiographic, and microscopic evaluation.Indirect and direct testing of the material gave no indication of the haemolytic effects of the material.Evaluation at time of autopsy showed a persistent occlusion with no systemic effects, no signs of embolization and mild effects on the arterial wall.

View Article: PubMed Central - PubMed

Affiliation: Department of Cardiac Surgery, UZ Leuven, Herestraat 49, 3000, Louvain, Belgium. peter.verbrugghe@uzleuven.be.

ABSTRACT
There is a growing interest in using hydrogels for biomedical applications, because of more favourable characteristics. Some of these hydrogels can be activated by using particular stimuli, for example electrical fields. These stimuli can change the hydrogel shape in a predefined way. It could make them capable of adaptation to patient-specific anatomy even post-implantation. This is the first paper aiming to describe in vivo studies of an electro-responsive, Pluronic F127 based hydrogel, for intravascular applications. Pluronic methacrylic acid hydrogel (PF127/MANa) was in vitro tested for its haemolytic and cytotoxic effects. Minimal invasive implantation in the carotid artery of sheep was used to evaluate its medium-term biological effects, through biochemical, macroscopic, radiographic, and microscopic evaluation. Indirect and direct testing of the material gave no indication of the haemolytic effects of the material. Determination of fibroblast viability after 24 h of incubation in an extract of the hydrogel showed no cytotoxic effects. Occlusion was obtained within 1 h following in vivo implantation. Evaluation at time of autopsy showed a persistent occlusion with no systemic effects, no signs of embolization and mild effects on the arterial wall. An important proof-of-concept was obtained showing biocompatibility and effectiveness of a pluronic based electro-responsive hydrogel for obtaining an arterial occlusion with limited biological impact. So the selected pluronic-methacrylic acid based hydrogel can be used as an endovascular occlusion device. More importantly it is the first step in further development of electro-active hydrogels for a broad range of intra-vascular applications (e.g. system to prevent endoleakage in aortic aneurysm treatment, intra-vascular drug delivery).

No MeSH data available.


Related in: MedlinePlus

a Gel sample showing a cellular reaction in media and adventitia (arrows); b Control sample of a normal carotid artery (I: intima; M: media; A: adventitia; H&E staining, ×100)
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4608972&req=5

Fig6: a Gel sample showing a cellular reaction in media and adventitia (arrows); b Control sample of a normal carotid artery (I: intima; M: media; A: adventitia; H&E staining, ×100)

Mentions: An overview of the microscopic evaluation is depicted in Table 1. Microscopy of the vessels showed that the intima was morphologically intact in all randomly taken samples. There was a mild inflammatory reaction in the media of samples that were in contact with the hydrogel (Fig. 6). No fibrotic reaction could be visualized and tissue fibres were intact. A mild inflammatory reaction was also visualized in the adventitia in comparison with the unaffected carotid artery. A specific evaluation of the ulcer in sheep 1172 showed disruption of the intima and an extensive fibrotic and inflammatory reaction in the media. There was a moderate decrease in media thickness after contact with the hydrogel with a mean value of 268 μm ± 131, versus 545 μm ± 102 in the control samples, respectively.Table 1


An electro-responsive hydrogel for intravascular applications: an in vitro and in vivo evaluation.

Verbrugghe P, Verhoeven J, Coudyzer W, Verbeken E, Dubruel P, Mendes E, Stam F, Meuris B, Herijgers P - J Mater Sci Mater Med (2015)

a Gel sample showing a cellular reaction in media and adventitia (arrows); b Control sample of a normal carotid artery (I: intima; M: media; A: adventitia; H&E staining, ×100)
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4608972&req=5

Fig6: a Gel sample showing a cellular reaction in media and adventitia (arrows); b Control sample of a normal carotid artery (I: intima; M: media; A: adventitia; H&E staining, ×100)
Mentions: An overview of the microscopic evaluation is depicted in Table 1. Microscopy of the vessels showed that the intima was morphologically intact in all randomly taken samples. There was a mild inflammatory reaction in the media of samples that were in contact with the hydrogel (Fig. 6). No fibrotic reaction could be visualized and tissue fibres were intact. A mild inflammatory reaction was also visualized in the adventitia in comparison with the unaffected carotid artery. A specific evaluation of the ulcer in sheep 1172 showed disruption of the intima and an extensive fibrotic and inflammatory reaction in the media. There was a moderate decrease in media thickness after contact with the hydrogel with a mean value of 268 μm ± 131, versus 545 μm ± 102 in the control samples, respectively.Table 1

Bottom Line: Minimal invasive implantation in the carotid artery of sheep was used to evaluate its medium-term biological effects, through biochemical, macroscopic, radiographic, and microscopic evaluation.Indirect and direct testing of the material gave no indication of the haemolytic effects of the material.Evaluation at time of autopsy showed a persistent occlusion with no systemic effects, no signs of embolization and mild effects on the arterial wall.

View Article: PubMed Central - PubMed

Affiliation: Department of Cardiac Surgery, UZ Leuven, Herestraat 49, 3000, Louvain, Belgium. peter.verbrugghe@uzleuven.be.

ABSTRACT
There is a growing interest in using hydrogels for biomedical applications, because of more favourable characteristics. Some of these hydrogels can be activated by using particular stimuli, for example electrical fields. These stimuli can change the hydrogel shape in a predefined way. It could make them capable of adaptation to patient-specific anatomy even post-implantation. This is the first paper aiming to describe in vivo studies of an electro-responsive, Pluronic F127 based hydrogel, for intravascular applications. Pluronic methacrylic acid hydrogel (PF127/MANa) was in vitro tested for its haemolytic and cytotoxic effects. Minimal invasive implantation in the carotid artery of sheep was used to evaluate its medium-term biological effects, through biochemical, macroscopic, radiographic, and microscopic evaluation. Indirect and direct testing of the material gave no indication of the haemolytic effects of the material. Determination of fibroblast viability after 24 h of incubation in an extract of the hydrogel showed no cytotoxic effects. Occlusion was obtained within 1 h following in vivo implantation. Evaluation at time of autopsy showed a persistent occlusion with no systemic effects, no signs of embolization and mild effects on the arterial wall. An important proof-of-concept was obtained showing biocompatibility and effectiveness of a pluronic based electro-responsive hydrogel for obtaining an arterial occlusion with limited biological impact. So the selected pluronic-methacrylic acid based hydrogel can be used as an endovascular occlusion device. More importantly it is the first step in further development of electro-active hydrogels for a broad range of intra-vascular applications (e.g. system to prevent endoleakage in aortic aneurysm treatment, intra-vascular drug delivery).

No MeSH data available.


Related in: MedlinePlus