scholarly journals In Vivo bone tissue induction by freeze-dried collagen-nanohydroxyapatite matrix loaded with BMP2/NS1 mRNAs lipopolyplexes

Author(s):  
Pinpin Wang ◽  
Federico Perche ◽  
Patrick Midoux ◽  
Catia S.D. Cabral ◽  
Virginie Malard ◽  
...  
Keyword(s):  
Author(s):  
N.K.R. Smith ◽  
K.E. Hunter ◽  
P. Mobley ◽  
L.P. Felpel

Electron probe energy dispersive x-ray microanalysis (XRMA) offers a powerful tool for the determination of intracellular elemental content of biological tissue. However, preparation of the tissue specimen , particularly excitable central nervous system (CNS) tissue , for XRMA is rather difficult, as dissection of a sample from the intact organism frequently results in artefacts in elemental distribution. To circumvent the problems inherent in the in vivo preparation, we turned to an in vitro preparation of astrocytes grown in tissue culture. However, preparations of in vitro samples offer a new and unique set of problems. Generally, cultured cells, growing in monolayer, must be harvested by either mechanical or enzymatic procedures, resulting in variable degrees of damage to the cells and compromised intracel1ular elemental distribution. The ultimate objective is to process and analyze unperturbed cells. With the objective of sparing others from some of the same efforts, we are reporting the considerable difficulties we have encountered in attempting to prepare astrocytes for XRMA.Tissue cultures of astrocytes from newborn C57 mice or Sprague Dawley rats were prepared and cultured by standard techniques, usually in T25 flasks, except as noted differently on Cytodex beads or on gelatin. After different preparative procedures, all samples were frozen on brass pins in liquid propane, stored in liquid nitrogen, cryosectioned (0.1 μm), freeze dried, and microanalyzed as previously reported.


2020 ◽  
Vol 27 (6) ◽  
pp. 838-853 ◽  
Author(s):  
Madalina Icriverzi ◽  
Valentina Dinca ◽  
Magdalena Moisei ◽  
Robert W. Evans ◽  
Mihaela Trif ◽  
...  

: Among the multiple properties exhibited by lactoferrin (Lf), its involvement in bone regeneration processes is of great interest at the present time. A series of in vitro and in vivo studies have revealed the ability of Lf to promote survival, proliferation and differentiation of osteoblast cells and to inhibit bone resorption mediated by osteoclasts. Although the mechanism underlying the action of Lf in bone cells is still not fully elucidated, it has been shown that its mode of action leading to the survival of osteoblasts is complemented by its mitogenic effect. Activation of several signalling pathways and gene expression, in an LRPdependent or independent manner, has been identified. Unlike the effects on osteoblasts, the action on osteoclasts is different, with Lf leading to a total arrest of osteoclastogenesis. : Due to the positive effect of Lf on osteoblasts, the potential use of Lf alone or in combination with different biologically active compounds in bone tissue regeneration and the treatment of bone diseases is of great interest. Since the bioavailability of Lf in vivo is poor, a nanotechnology- based strategy to improve the biological properties of Lf was developed. The investigated formulations include incorporation of Lf into collagen membranes, gelatin hydrogel, liposomes, loading onto nanofibers, porous microspheres, or coating onto silica/titan based implants. Lf has also been coupled with other biologically active compounds such as biomimetic hydroxyapatite, in order to improve the efficacy of biomaterials used in the regulation of bone homeostasis. : This review aims to provide an up-to-date review of research on the involvement of Lf in bone growth and healing and on its use as a potential therapeutic factor in bone tissue regeneration.


2020 ◽  
Vol 17 (3) ◽  
pp. 207-217
Author(s):  
Eman A. Hakeem ◽  
Galal M. El-Mahrouk ◽  
Ghada Abdelbary ◽  
Mahmoud H. Teaima

Background: Clopidogrel (CLP) suffers from extensive first pass metabolism results in a negative impact on its oral systemic bioavailability. Cubosomes are Lyotropic Liquid Crystalline (LLC) nano-systems comprising monoolein, a steric stabilizer and an aqueous system, it considered a promising carrier for different pharmaceutical compounds. Box-Behnken Design (BBD) is an efficient tool for process analysis and optimization skipping forceful treatment combinations. Objective: The study was designed to develop freeze-dried clopidogrel loaded LLC (cubosomes) for enhancement of its oral bioavailability. Methods: A 33 BBD was adopted, the studied independent factors were glyceryl monooleate (GMO lipid phase), Pluronic F127 (PL F127steric stabilizer) and polyvinyl alcohol powder (stabilizer). Particle Size (PS), Polydispersity Index (PDI) and Zeta Potential (ZP) were set as independent response variables. Seventeen formulae were prepared in accordance with the bottom up approach and in-vitro evaluated regarding PS, PDI and ZP. Statistical analysis and optimization were achieved using design expert software®, then the optimum suggested formula was prepared, in-vitro revaluated, freeze-dried with 3% mannitol (cryoprotectant), solid state characterized and finally packed in hard gelatin capsule for comparative in-vitro release and in-vivo evaluation to Plavix®. Results: Results of statistical analysis of each individual response revealed a quadratic model for PS and PDI where a linear model for ZP. The optimum suggested formula with desirability factor equal 0.990 consisting of (200 mg GMO, 78.15 mg PL F127 and 2% PVA). LC/MS/MS study confirmed significant higher C>max, AUC>0-24h and AUC>0-∞ than that of Plavix®. Conclusion: The results confirm the capability of developed carrier to overcome the low oral bioavailability.


Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1611
Author(s):  
Caroline J. Harrison ◽  
Paul V. Hatton ◽  
Piergiorgio Gentile ◽  
Cheryl A. Miller

Injectable nanoscale hydroxyapatite (nHA) systems are highly promising biomaterials to address clinical needs in bone tissue regeneration, due to their excellent biocompatibility, bioinspired nature, and ability to be delivered in a minimally invasive manner. Bulk strontium-substituted hydroxyapatite (SrHA) is reported to encourage bone tissue growth by stimulating bone deposition and reducing bone resorption, but there are no detailed reports describing the preparation of a systematic substitution up to 100% at the nanoscale. The aim of this work was therefore to fabricate systematic series (0–100 atomic% Sr) of SrHA pastes and gels using two different rapid-mixing methodological approaches, wet precipitation and sol-gel. The full range of nanoscale SrHA materials were successfully prepared using both methods, with a measured substitution very close to the calculated amounts. As anticipated, the SrHA samples showed increased radiopacity, a beneficial property to aid in vivo or clinical monitoring of the material in situ over time. For indirect methods, the greatest cell viabilities were observed for the 100% substituted SrHA paste and gel, while direct viability results were most likely influenced by material disaggregation in the tissue culture media. It was concluded that nanoscale SrHAs were superior biomaterials for applications in bone surgery, due to increased radiopacity and improved biocompatibility.


2021 ◽  
Vol 25 (1) ◽  
Author(s):  
Thakoon Thitiset ◽  
Siriporn Damrongsakkul ◽  
Supansa Yodmuang ◽  
Wilairat Leeanansaksiri ◽  
Jirun Apinun ◽  
...  

Abstract Background A novel biodegradable scaffold including gelatin (G), chitooligosaccharide (COS), and demineralized bone matrix (DBM) could play a significant part in bone tissue engineering. The present study aimed to investigate the biological characteristics of composite scaffolds in combination of G, COS, and DBM for in vitro cell culture and in vivo animal bioassays. Methods Three-dimensional scaffolds from the mixture of G, COS, and DBM were fabricated into 3 groups, namely, G, GC, and GCD using a lyophilization technique. The scaffolds were cultured with mesenchymal stem cells (MSCs) for 4 weeks to determine biological responses such as cell attachment and cell proliferation, alkaline phosphatase (ALP) activity, calcium deposition, cell morphology, and cell surface elemental composition. For the in vivo bioassay, G, GC, and GCD, acellular scaffolds were implanted subcutaneously in 8-week-old male Wistar rats for 4 weeks and 8 weeks. The explants were assessed for new bone formation using hematoxylin and eosin (H&E) staining and von Kossa staining. Results The MSCs could attach and proliferate on all three groups of scaffolds. Interestingly, the ALP activity of MSCs reached the greatest value on day 7 after cultured on the scaffolds, whereas the calcium assay displayed the highest level of calcium in MSCs on day 28. Furthermore, weight percentages of calcium and phosphorus on the surface of MSCs after cultivation on the GCD scaffolds increased when compared to those on other scaffolds. The scanning electron microscopy images showed that MSCs attached and proliferated on the scaffold surface thoroughly over the cultivation time. Mineral crystal aggregation was evident in GC and greatly in GCD scaffolds. H&E staining illustrated that G, GC, and GCD scaffolds displayed osteoid after 4 weeks of implantation and von Kossa staining confirmed the mineralization at 8 weeks in G, GC, and GCD scaffolds. Conclusion The MSCs cultured in GCD scaffolds revealed greater osteogenic differentiation than those cultured in G and GC scaffolds. Additionally, the G, GC, and GCD scaffolds could promote in vivo ectopic bone formation in rat model. The GCD scaffolds exhibited maximum osteoinductive capability compared with others and may be potentially used for bone regeneration.


2021 ◽  
Vol 11 (6) ◽  
pp. 2493
Author(s):  
Karol Kirstein ◽  
Michalina Horochowska ◽  
Jacek Jagiełło ◽  
Joanna Bubak ◽  
Aleksander Chrószcz ◽  
...  

The bone tissue destruction during drilling is still one of the crucial problems in implantology. In this study, the influence of drilling speed, coolant presence, and its temperature on bone tissue was tested using swine rib as a biological model of human jaws. The same method of drilling (with or without coolant) was used in all tested samples. The microscopic investigation estimated the size of the destruction zone and morphology of bone tissue surrounding the drilling canal. The achieved results were statistically elaborated. The study proved that the optimal drilling speed was ca. 1200 rpm, but the temperature of the used coolant had no significant influence on provoked bone destruction. Simultaneously, the drilling system without coolant compared to this with coolant has statistical importance on drilling results. Further in vivo studies will verify the obtained results.


2015 ◽  
Vol 2 (11) ◽  
pp. 150496 ◽  
Author(s):  
Fabian Westhauser ◽  
Christian Weis ◽  
Melanie Hoellig ◽  
Tyler Swing ◽  
Gerhard Schmidmaier ◽  
...  

Bone tissue engineering and bone scaffold development represent two challenging fields in orthopaedic research. Micro-computed tomography (mCT) allows non-invasive measurement of these scaffolds’ properties in vivo . However, the lack of standardized mCT analysis protocols and, therefore, the protocols’ user-dependency make interpretation of the reported results difficult. To overcome these issues in scaffold research, we introduce the Heidelberg-mCT-Analyzer. For evaluation of our technique, we built 10 bone-inducing scaffolds, which underwent mCT acquisition before ectopic implantation (T0) in mice, and at explantation eight weeks thereafter (T1). The scaffolds’ three-dimensional reconstructions were automatically segmented using fuzzy clustering with fully automatic level-setting. The scaffold itself and its pores were then evaluated for T0 and T1. Analysing the scaffolds’ characteristic parameter set with our quantification method showed bone formation over time. We were able to demonstrate that our algorithm obtained the same results for basic scaffold parameters (e.g. scaffold volume, pore number and pore volume) as other established analysis methods. Furthermore, our algorithm was able to analyse more complex parameters, such as pore size range, tissue mineral density and scaffold surface. Our imaging and post-processing strategy enables standardized and user-independent analysis of scaffold properties, and therefore is able to improve the quantitative evaluations of scaffold-associated bone tissue-engineering projects.


2018 ◽  
Vol 36 (10) ◽  
pp. 2595-2603 ◽  
Author(s):  
Robert Meertens ◽  
Francesco Casanova ◽  
Karen M. Knapp ◽  
Clare Thorn ◽  
William David Strain

2016 ◽  
Vol 4 (10) ◽  
pp. 1827-1841 ◽  
Author(s):  
Han-Tsung Liao ◽  
K. T. Shalumon ◽  
Kun-Hung Chang ◽  
Chialin Sheu ◽  
Jyh-Ping Chen

Gelatin cryogels modified with nHAP and BMP-2 could provide cues to promote the osteogenesis of ADSCs in vitro and in vivo.


Zygote ◽  
2007 ◽  
Vol 15 (1) ◽  
pp. 15-24 ◽  
Author(s):  
M. Nakai ◽  
N. Kashiwazaki ◽  
A. Takizawa ◽  
N. Maedomari ◽  
M. Ozawa ◽  
...  

SUMMARYSuccessful offspring production after intracytoplasmic injection of freeze-dried sperm has been reported in laboratory animals but not in domesticated livestock, including pigs. The integrity of the DNA in the freeze-dried sperm is reported to affect embryogenesis. Release of endonucleases from the sperm is one of the causes of induction of sperm DNA fragmentation. We examined the effects of chelating agents, which inhibit the activation of such enzymes, on DNA fragmentation in freeze-dried sperm and on the in vitro and in vivo developmental ability of porcine oocytes following boar sperm head injection. Boar ejaculated sperm were sonicated, suspended in buffer supplemented with (1) 50 mM EGTA, (2) 50 mM EDTA, (3) 10 mM EDTA, or (4) no chelating agent and freeze-dried. A fertilization medium (Pig-FM) was used as a control. The rehydrated spermatozoa in each group were then incubated in Pig-FM at room temperature. The rate of DNA fragmentation in the control group, as assessed by the TUNEL method, increased gradually as time after rehydration elapsed (2.8% at 0 min to 12.2% at 180 min). However, the rates in all experimental groups (1–4) did not increase, even at 180 min (0.7–4.1%), which were all significantly lower (p < 0.05) than that of the control group. The rate of blastocyst formation after the injection in the control group (6.0%) was significantly lower (p < 0.05) than those in the 50 mM EGTA (23.1%) and 10 mM EDTA (22.6%) groups incubated for 120–180 min. The average number of blastocyst cells in the 50 mM EGTA group (33.1 cells) was significantly higher (p < 0.05) than that in the 10 mM EDTA group (17.8 cells). Finally, we transferred oocytes from 50 mM EGTA or control groups incubated for 0–60 min into estrous-synchronized recipients. The two recipients of the control oocytes became pregnant and one miscarried two fetuses on day 39.The results suggested that fragmentation of DNA in freeze-dried boar sperm is one of the causes of decreased in vitro developmental ability of injected oocytes to the blastocyst stage. Supplementation with EGTA in a freeze-drying buffer improves this ability.


Sign in / Sign up

Export Citation Format

Share Document