A “noisy” electrical stimulation protocol favors muscle regeneration in vitro through release of endogenous ATP

SummaryThe present study was designed to evaluate the effectiveness of the ergoline 5HT2 receptor antagonist, LY53857 in a rabbit model of vascular arterial occlusion. LY53857 (1 and 10 εM) inhibited serotonin amplified platelet aggregation responses to threshold concentrations of ADP in rabbit platelets in vitro. LY53857 (1 εM) not only inhibited the serotonin component of rabbit platelet aggregation, but also inhibited in vitro aggregation induced by ADP (48.7 ± 16.7% inhibition), collagen (76.1 ± 15.9% inhibition) and U46619 (65.2 ± 12.3% inhibition). The effectiveness of this ergoline 5HT2 receptor antagonist in blocking aggregation to ADP, collagen and U46619 may be related to its ability to inhibit a serotonin component of platelet aggregation since rabbit platelets possess high concentrations of serotonin that may be released during aggregation produced by other agents. Based on the effectiveness of LY53857 to inhibit rabbit platelet aggregation, we explored the ability of LY53857 to extend the time to carotid artery occlusion in rabbits following electrical stimulation of the artery. Reproducible carotid artery occlusion was induced in rabbits by moderate stenosis coupled to arterial cross clamping, followed by electrical stimulation. With this procedure, occlusion occurred at 47.0 ± 7 min (n = 30) after initiation of the electrical stimulation. Animals pretreated with LY53857 (50 to 500 εg/kg i.v.) showed a delay in the time to carotid artery occlusion (at 100 εg/kg i.v. occlusion time extended to 164 ± 16 min). Furthermore, ex vivo platelet aggregation from animals treated with LY53857 (300 εg/kg i.v.) resulted in 40.5% inhibition of platelet aggregation in response to the combination of ADP (1 εM) and serotonin (1 εM). These studies document the ability to obtain reproducible arterial occlusion in the rabbit and showed that intravenously administered LY53857 prolonged the time to carotid artery occlusion. Prolongation of carotid artery occlusion time was accompanied by inhibition of serotonin-amplified ADP-induced aggregation in rabbit platelets, an effect observed both in vitro and ex vivo. Thus, the rabbit is a useful model for studying the effectiveness of 5HT2 receptor antagonists in prolonging vascular occlusion induced by insult of the carotid artery.

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The effect of benzyladenine on shoot regeneration in vitro of Zantedeschia aethiopica ‘Green Goddess’

Annales UMCS Horticultura ◽

10.2478/v10084-009-0003-5 ◽

2009 ◽

Vol 19 (1) ◽

Cited By ~ 1

Author(s):

Danuta Kozak ◽

Magdalena Stelmaszczuk

Keyword(s):

Shoot Regeneration ◽

Zantedeschia Aethiopica ◽

Regeneration In Vitro

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Mild Stimulation Protocol Using Clomiphene Citrate for Women With PCOS Undergoing in Vitro Fertilization

Case Medical Research ◽

10.31525/ct1-nct04157725 ◽

2019 ◽

Author(s):

Keyword(s):

In Vitro Fertilization ◽

Clomiphene Citrate ◽

Stimulation Protocol ◽

Vitro Fertilization ◽

Mild Stimulation

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Recycled algae-based carbon materials as electroconductive 3D printed skeletal muscle tissue engineering scaffolds

Journal of Materials Science Materials in Medicine ◽

10.1007/s10856-021-06534-6 ◽

2021 ◽

Vol 32 (7) ◽

Author(s):

Selva Bilge ◽

Emre Ergene ◽

Ebru Talak ◽

Seyda Gokyer ◽

Yusuf Osman Donar ◽

...

Keyword(s):

Skeletal Muscle ◽

Tissue Engineering ◽

Electrical Stimulation ◽

Muscle Tissue ◽

Carbonaceous Material ◽

Hydrothermal Carbonization ◽

Skeletal Muscle Tissue ◽

Myotube Formation ◽

3D Printed

AbstractSkeletal muscle is an electrically and mechanically active tissue that contains highly oriented, densely packed myofibrils. The tissue has self-regeneration capacity upon injury, which is limited in the cases of volumetric muscle loss. Several regenerative therapies have been developed in order to enhance this capacity, as well as to structurally and mechanically support the defect site during regeneration. Among them, biomimetic approaches that recapitulate the native microenvironment of the tissue in terms of parallel-aligned structure and biophysical signals were shown to be effective. In this study, we have developed 3D printed aligned and electrically active scaffolds in which the electrical conductivity was provided by carbonaceous material (CM) derived from algae-based biomass. The synthesis of this conductive and functional CM consisted of eco-friendly synthesis procedure such as pre-carbonization and multi-walled carbon nanotube (MWCNT) catalysis. CM obtained from biomass via hydrothermal carbonization (CM-03) and its ash form (CM-03K) were doped within poly(ɛ-caprolactone) (PCL) matrix and 3D printed to form scaffolds with aligned fibers for structural biomimicry. Scaffolds were seeded with C2C12 mouse myoblasts and subjected to electrical stimulation during the in vitro culture. Enhanced myotube formation was observed in electroactive groups compared to their non-conductive counterparts and it was observed that myotube formation and myotube maturity were significantly increased for CM-03 group after electrical stimulation. The results have therefore showed that the CM obtained from macroalgae biomass is a promising novel source for the production of the electrically conductive scaffolds for skeletal muscle tissue engineering.

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