Plasma polypyrrole implants recover motor function in rats after spinal cord transection

Cruz, Guillermo J.; Mondragón-Lozano, Rodrigo; Dı́az-Ruiz, Araceli; Manjarrez, J.; Olayo, Roberto; Salgado–Ceballos, Hermelinda; Olayo, M. G.; Morales, J.; Mejía, Ana Laura Álvarez; Morales, Axayacatl; Méndez‐Armenta, Marisela; Plascencia, Noel; Fernández, María del Carmen; Rı́os, Camilo

doi:10.1007/s10856-012-4715-2

Cited by 32 publications

(38 citation statements)

References 25 publications

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“…Because others have described the functional improvement after implantation of different biopolymers to be modest (for review see [33]), one of the goal of the present work was to increase the potential beneficial effects that our research group obtained before using implantation of PPy/I [18,19]. Thus, this therapeutic strategy was used in combination with locomotor training on a treadmill.…”

Section: Discussionmentioning

confidence: 99%

“…The synthetic polymers used in an injured spinal cord until now have been poly(2-hidroxy-ethyl methacrylate) or poly(2-hidroxy-ethyl methacrylate)-co-methyl methacrylate (PHEMA/PHEMA-MMA), which increase angiogenesis and axonal regeneration [15,16]; poly[N-(2-hydroxypropyl)methacrylamide] (PHPMA), which induces the myelination of axons and reduces astrocytosis and glial scar formation [17]; and polypyrrole (PPy) polymer, which our research group has shown exhibits neuroprotective effects through increasing the amount of preserved spinal cord tissue and increases the functional recovery [18,19]. The combined strategies include the three-dimensional nanofibrous core-sheath scaffold with a nanorough sheath and alginate core constructed on the poly(lactic-co-glycolic acid) or PGLA scaffolds, which supports axon regeneration and functional recovery after a TSCI by hemisection [20].…”

Section: Introductionmentioning

confidence: 99%

“…A noncontaminant method that uses electric variables instead of chemical reagents to induce the polymerization is the synthesis by plasma, which only requires the monomer (pyrrole) and dopants, without other potentially harmful compounds [23]. Our research group has used PPy iodinedoped (PPy/I) polymer synthesized by plasma for implantation into the transected spinal cord tissue, where we showed that polymer is biocompatible and is able to reduce the inflammatory response, increase tissue preservation and improve functional recovery after a lesion [18,19]; however, the results have also shown that it is necessary to apply an additional therapeutic option to improve the functional recovery.…”

Section: Introductionmentioning

confidence: 99%

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Functional recovery in spinal cord injured rats using polypyrrole/iodine implants and treadmill training

Álvarez-Mejía

Morales

Cruz

et al. 2015

J Mater Sci: Mater Med

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Currently, there is no universally accepted treatment for traumatic spinal cord injury (TSCI), a pathology that can cause paraplegia or quadriplegia. Due to the complexity of TSCI, more than one therapeutic strategy may be necessary to regain lost functions. Therefore, the present study proposes the use of implants of mesoparticles (MPs) of polypyrrole/iodine (PPy/I) synthesized by plasma for neuroprotection promotion and functional recovery in combination with treadmill training (TT) for neuroplasticity promotion and maintenance of muscle tone. PPy/I films were synthesized by plasma and pulverized to obtain MPs. Rats with a TSCI produced by the NYU impactor were divided into four groups: Vehicle (saline solution); MPs (PPy/I implant); Vehicle-TT (saline solution + TT); and MPs-TT (PPy/I implant + TT). The vehicle or MPs (30 μL) were injected into the lesion site 48 h after a TSCI. Four days later, TT was carried out 5 days a week for 2 months. Functional recovery was evaluated weekly using the BBB motor scale for 9 weeks and tissue protection using histological and morphometric analysis thereafter. Although the MPs of PPy/I increased nerve tissue preservation (P = 0.03) and promoted functional recovery (P = 0.015), combination with TT did not produce better neuroprotection, but significantly improved functional results (P = 0.000) when comparing with the vehicle group. So, use these therapeutic strategies by separately could stimulate specific mechanisms of neuroprotection and neuroregeneration, but when using together they could mainly potentiate different mechanisms of neuronal plasticity in the preserved spinal cord tissue after a TSCI and produce a significant functional recovery. The implant of mesoparticles of polypyrrole/iodine into the injured spinal cord displayed good integration into the nervous tissue without a response of rejection, as well as an increased in the amount of preserved tissue and a better functional recovery than the group without transplant after a traumatic spinal cord injury by contusion in rats. The relevance of the present results is that polypyrrole/iodine implants were synthesized by plasma instead by conventional chemical or electrochemical methods. Synthesis by plasma modifies physicochemical properties of polypyrrole/iodine implants, which can be responsible of the histological response and functional results. Furthermore, no additional molecules or trophic factors or cells were added to the implant for obtain such results. Even more, when the implant was used together with physical rehabilitation, better functional recovery was obtained than that observed when these strategies were used by separately.

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Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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Functional recovery in spinal cord injured rats using polypyrrole/iodine implants and treadmill training

Álvarez-Mejía

Morales

Cruz

et al. 2015

J Mater Sci: Mater Med

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“…It has been also reported that these plasma combinations of Py and EG can be used as implants in the spinal cord of rats after a severe injury to prevent secondary destruction in the spinal cord tissues and to partially recover the lost motor functions [9,10]. In view of this important use, in this work, the main atomic chemical states of plasma PEG/PPy/I copolymers are studied by XPS considering the energetic distribution of C1s, O1s, N1s, and I3d atomic orbitals with the purpose to identify and quantify the structure in the copolymers.…”

Section: Introductionmentioning

confidence: 99%

XPS Study of the Chemical Structure of Plasma Biocopolymers of Pyrrole and Ethylene Glycol

González-Torres

Olayo

Cruz

et al. 2014

Advances in Chemistry

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An XPS study about the structure of plasma biocopolymers synthesized with resistive radio frequency glow discharges and random combinations of ethylene glycol, pyrrole, and iodine, as a dopant, is presented in this work. The collisions of molecules produced structures with a great variety of chemical states based in the monomers, their combinations, crosslinking, doping, fragmentation, and oxidation at different levels in the plasma environment. Iodine appears bonded in the copolymers only at high power of synthesis, mainly as C-I and N-I chemical bonds. Multiple bonds as C≡C, C≡N, C=O, and C=N were found in the copolymers, without belonging to the initial reagents, and were generated by dehydrogenation of intermediate compounds during the polymerization. The main chemical states on PEG/PPy/I indicate that all atoms in pyrrole rings participate in the polymerization resulting in crosslinked, partially fragmented, and highly oxidized structures. This kind of analysis can be used to modify the synthesis of polymers to increase the participation of the most important chemical states in their biofunctions.

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“…Ppy coating has been used on cell culture as in spinal cord injuries in vivo experiments (Cruz, 2012 (Risbud, 2003). In addition to increasing the production of certain proteins and metabolites in hepatocytes when used in co-cultures in bioreactors (RamirezFernandez, 2012; Risbud, 2003).…”

Section: Introductionmentioning

confidence: 99%

Organic-polymeric radial flow biorreactor for liver models

Ramírez-Fernández

Zúñiga-Aguilar

Gómez-Quiroz

et al.

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An artificial liver support system is based on the functional hepatocytes being cultured inside a bioreactor; this technique has being used as an effective therapy for treating chronic liver diseases in recent times. This work evaluates different parameters such as cell viability and metabolic function of the hepatocytes when cultured on a hybrid scaffold. The scaffold was built using a polypyrrole plasma coated polymer layer seeded with endothelial matrix for efficient three-dimensional hepatocyte growth within a radial flow bioreactor. The flow rate inside the bioreactor was 7 ml / min. The parts for the bioreactor where either built using food-grade steel and/or glass or the scaffolds comprise a Poly (L-lactic acid)-coated polypyrrole iodine layer or not for HepG2 culture. The results show that the Poly (L-lactic acid)-coated scaffolds increased cell proliferation by 30%, protein production by 16% and albumin secretion by 40% compared with the non-coated scaffold. All experiments were performed thrice and data was analysed by ANOVA and Tukey statistic models with a p<0.05. The obtained results demonstrated that radial flow bioreactors in conjunction with hybrid scaffolds improve hepatocytes' physiological and functional properties and could be used as an alternative therapy for patients with liver diseases.Keywords: hepatocytes, glow discharge polymerization, polypyrrole, PLLA, HUVEC, biorreactor. Correspondencia:Odin Ramírez-Fernández 166 Revista Mexicana de Ingeniería Biomédica · volumen 37 · número 3 · Sep-Dic, 2016 RESUMENUn sistema de soporte hepático artificial se basa en utilizar hepatocitos funcionales cultivados en un biorreactor; esta técnica ha demostrado que se puede utilizar como una terapia eficaz para el tratamiento de enfermedades crónicas del hígado en los últimos tiempos. Este trabajo evalúa diferentes parámetros tales como la viabilidad celular y la función metabólica de los hepatocitos cuando se cultivan en un andamio híbrido. El andamio fue construido usando una capa de polímero recubierto de polipirrol plasma, se sembró con un cultivo tridimensional de células endoteliales y de hepatocitos dentro de un biorreactor de flujo radial. La velocidad de flujo en el interior del biorreactor fue de 7 ml / min. Las piezas para el biorreactor fueron construidas con acero de calidad alimentaria y / o vidrio. Los andamios control fueron de ácido L-poliláctico y a estos se les agrego un revestimiento de polipirrol-yodo para el cultivo de HepG2. Los resultados muestran que el ácido L-poliláctico recubierto, aumento la proliferación celular en un 30%, la producción de proteínas en un 16% y la secreción de albúmina por 40% en comparación con el andamio no recubierto. Todos los experimentos se llevaron a cabo tres veces y los datos se analizaron mediante modelos estadísticos ANOVA y Tukey con una p <0.05. Los resultados obtenidos demostraron que los biorreactores de flujo radial conjuntamente con andamios híbridos mejoran las propiedades fisiológicas y funcionales hepatocitos y podrían utilizarse ...

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Plasma polypyrrole implants recover motor function in rats after spinal cord transection

Cited by 32 publications

References 25 publications

Functional recovery in spinal cord injured rats using polypyrrole/iodine implants and treadmill training

Functional recovery in spinal cord injured rats using polypyrrole/iodine implants and treadmill training

XPS Study of the Chemical Structure of Plasma Biocopolymers of Pyrrole and Ethylene Glycol

Organic-polymeric radial flow biorreactor for liver models

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