scholarly journals In vivo transdifferentiation, osteoconductive and osteoinductive properties of experimental water-soluble organo-biomaterials – A Pilot Study

2021 ◽  
Vol 10 (5) ◽  
pp. e45310515017
Author(s):  
Viviane Rozeira Crivellaro ◽  
Gilvan Spada ◽  
Cláudia Salete Judachesci ◽  
Paula Porto Spada ◽  
Luiza Rodrigues Saling ◽  
...  

Inorganic bovine bone matrix (IBBM) is a biomaterial with proven osteoconductive functionalities. The objective of this study was to assess the in vivo bone regeneration functionalities of IBBM modified or not by an experimental MOE in sheep. MOE synthesis was performed by suspending nacre particles (0.05 g, diameters < 0.01 mm) in anhydrous acetic acid (pH 7, 5 mL, 25°C, 72 hours) using magnetic stirring. Polyethylene carriers (d= 5.0 mm, l= 10.0 mm, open ends) of negative control (sham) or experimental groups (IBBM or MOE-modified IBBM) were placed (n=3 conditions /animal; intramuscularly) adjacent to the lower spine of adult sheep (8 animals, » 45 Kg, 2 years old). Tissues were harvested (at 3 or 6 months) after implantation in preparation for histological (H), morphometrical (MM) and immunohistochemical analyses (IH; Wnt-3a, CD34, Vimentin and PREF-1). MM data were tested for normality and variance homogeneity using the Shapiro-Wilk and Levene tests, and Mann Whitney and Kruskal-Wallis, respectively. IM data were analyzed using two-way ANOVA and Tukey tests. Differences (p < 0.05) were observed between experimental groups (IBBM and IBBM+MOE at both 3 and 6 months) and controls (sham) for total area; Differences were not found for presence of remnant particles among experimental groups. The highest formation of bone was observed with IBBM+MOE (6-months). No differences (p > 0.05) were found on IM analysis (CD34, Vimentin, PREF-1, Wnt3a). Results indicated that experimental materials (IBBM+MOE) display promising functionalities. Additional studies are necessary to define biomaterials’ longitudinal effects and long-term biocompatibility properties.

Author(s):  
A. Rosenberg ◽  
Aliassghar Tofighi ◽  
N. Camacho ◽  
J. Chang

A new class of osteoconductive and osteoinductive combination biomaterials composed of calcium phosphate cement (CPC), demineralized bone matrix (DBM) and a water-soluble viscosity modifier were prepared and characterized in-vitro and in-vivo. In previous studies, a range of combinations formulations were tested in order to compare their performance characteristic. In-vitro characterization results show that the mechanical strength is decreased when the amount of DBM increases. However, DBM does not affect the CPC’s ability to set hard and convert to nanocrystalline apatitic calcium phosphate, which shares the chemical structure of natural bone as seen in x-ray diffraction. It is known that the DBM alone is osteoinductive. In-vivo osteoinductivity testing of the formulations in an intramuscular, athymic rat model demonstrated that the combination material is also osteoinductive. Two formulations were chosen for in-vivo efficacy testing based on the results of in-vitro and in-vivo characterization. These formulations were studied using rabbit critical-sized femoral core defect model. The formulations were composed of DBM with particle sizes of 250 to 710 μm, carboxymethyl-cellulose (CMC) as the viscosity modifier and weight percent compositions of 50% DBM/ 45% CPC/ 5% CMC and 60% DBM/ 30% CPC/ 10% CMC. Bone integration and healing was graded at 6, 12, and 24 weeks. The two formulations were compared to the gold standard autograft at 12 weeks and to an empty defect as the negative control at 24 weeks. Based on micro-computed topography (μCT), both formulations allowed for continuity of bone throughout the defect region at all time points. No differences in dense area fraction were seen between two formulations at 6 weeks (p = 0.8661). There was no significant statistical difference between the two formulations and autograft at 12 weeks (p = 0.2467). At 24 weeks, both formulations had significantly higher dense area fractions than empty controls (p = 0.0001). Histologically, the biology of the treatment areas appeared to have returned to normal by 24 weeks with CPC appearing to be the principal osteogenic inducer. In conclusion, these combinations of CPC and DBM offers significant advantages (handling, mechanical properties and osteoinductivity) over current DBM products and can be an effective alternative to autograft in healing of bone defects.


2006 ◽  
Vol 290 (4) ◽  
pp. F789-F794 ◽  
Author(s):  
Yasin Tayem ◽  
Tony R. Johnson ◽  
Brian E. Mann ◽  
Colin J. Green ◽  
Roberto Motterlini

Nephrotoxicity is one of the main side effects caused by cisplatin (CP), a widely used antineoplastic agent. Here, we examined the effect of a novel water-soluble carbon monoxide-releasing molecule (CORM-3) on CP-mediated cytotoxicity in renal epithelial cells and explored the potential therapeutic benefits of carbon monoxide in CP-induced nephrotoxicity in vivo. Exposure of LLC-PK1 cells to CP (50 μM) caused significant apoptosis as evidenced by caspase-3 activation and an increased number of floating cells. Treatment with CORM-3 (1–50 μM) resulted in a remarkable and concentration-dependent decrease in CP-induced caspase-3 activity and cell detachment. This effect involved activation of the cGMP pathway as 1H-oxadiazole [4, 3-a] quinoxaline-1-ore (ODQ), a guanylate cyclase inhibitor, completely abolished the protection elicited by CORM-3. Using a rat model of CP-induced renal failure, we found that treatment with CP (7.5 mg/kg) caused a significant elevation in plasma urea (6.6-fold) and creatinine (3.1-fold) levels, which was accompanied by severe morphological changes and marked apoptosis in tubules at the corticomedullary junction. A daily administration of CORM-3 (10 mg/kg ip), starting 1 day before CP treatment and continuing for 3 days thereafter, resulted in amelioration of renal function as shown by reduction of urea and creatinine levels to basal values, a decreased number of apoptotic tubular cells, and an improved histological profile. A negative control (iCORM-3) that is incapable of liberating CO failed to prevent renal dysfunction mediated by CP, indicating that CO is directly involved in renoprotection. Our data demonstrate that CORM-3 can be used as an effective therapeutic adjuvant in the treatment of CP-induced nephrotoxicity.


2018 ◽  
Vol 132 (9) ◽  
pp. 959-983 ◽  
Author(s):  
Karlhans Fru Che ◽  
Ellen Tufvesson ◽  
Sara Tengvall ◽  
Elisa Lappi-Blanco ◽  
Riitta Kaarteenaho ◽  
...  

Long-term tobacco smokers with chronic obstructive pulmonary disease (COPD) or chronic bronchitis display an excessive accumulation of neutrophils in the airways; an inflammation that responds poorly to established therapy. Thus, there is a need to identify new molecular targets for the development of effective therapy. Here, we hypothesized that the neutrophil-mobilizing cytokine interleukin (IL)-26 (IL-26) is involved in airway inflammation amongst long-term tobacco smokers with or without COPD, chronic bronchitis or colonization by pathogenic bacteria. By analyzing bronchoalveolar lavage (BAL), bronchail wash (BW) and induced sputum (IS) samples, we found increased extracellular IL-26 protein in the airways of long-term smokers in vivo without further increase amongst those with clinically stable COPD. In human alveolar macrophages (AM) in vitro, the exposure to water-soluble tobacco smoke components (WTC) enhanced IL-26 gene and protein. In this cell model, the same exposure increased gene expression of the IL-26 receptor complex (IL10R2 and IL20R1) and nuclear factor κ B (NF-κB); a proven regulator of IL-26 production. In the same cell model, recombinant human IL-26 in vitro caused a concentration-dependent increase in the gene expression of NF-κB and several pro-inflammatory cytokines. In the long-term smokers, we also observed that extracellular IL-26 protein in BAL samples correlates with measures of lung function, tobacco load, and several markers of neutrophil accumulation. Extracellular IL-26 was further increased in long-term smokers with exacerbations of COPD (IS samples), with chronic bronchitis (BAL samples ) or with colonization by pathogenic bacteria (IS and BW samples). Thus, IL-26 in the airways emerges as a promising target for improving the understanding of the pathogenic mechanisms behind several pulmonary morbidities in long-term tobacco smokers.


1998 ◽  
Vol 12 (1) ◽  
pp. 27-32 ◽  
Author(s):  
Henriette L. Verwoerd-Verhoef ◽  
Jim K. Bean ◽  
Gerjo J.V.M. Van Osch ◽  
Paul G.J. Ten Koppel ◽  
Jaap A. Meeuwis ◽  
...  

In the craniofacial region, defects of cartilage structures are preferably reconstructed with autologous cartilage. Donor-site morbidity related to the creation of a new defect elsewhere, and a lack of growth potential of the graft—mandatory in children—have stimulated investigators to find other ways to generate new “extra” cartilage. Several biomaterials have been tested as a matrix for the ingrowth of (peri)chondroblasts in experimental animals. In young (growing) rabbits we have developed a process of heterotopic cartilage induction with the use of a demineralized (bovine) bone matrix which is enfolded in a pedicled flap of ear perichondrium for at least three weeks. During this period the demineralized matrix is colonized by macrophages and polymorphonuclear cells which start a process of complete biodegradation of the material. Simultaneously, the collagen matrix is invaded by mesenchymal cells, originating from the perichondrium and differentiating into chondroblasts and later, into chondrocytes forming the intercellular substance. The developing, very young cartilage could be demonstrated as collagen type II, thus, hyaline cartilage. When applied with its adherent perichondrium as a graft, it merges easily with the more matured host cartilage and even appears to be capable of further growth. Therefore, it seems suitable for the reconstruction of a cartilaginous defect in growing cartilaginous structures like the nasal septum or the larynx.


2004 ◽  
Vol 43 (01) ◽  
pp. 26-32 ◽  
Author(s):  
F. Bruchertseifer ◽  
M. Bock ◽  
H. Kessler ◽  
M. Schwaiger ◽  
H.-J. Wester ◽  
...  

Summary Aim: The αvβ3 integrin is involved in tumour induced angiogenesis and tumour metastasis. We describe the synthesis and evaluation of a 99mTc-labelled RGD analogue for the visualisation of αvβ3 integrin expression. Methods: The linear peptides were assembled on a solid support. Cyclisation was performed under high dilution conditions. For conjugation with the chelator peptide, a water soluble carbodiimide was used. Radiolabelling was carried out due to standard procedures with high radiochemical yield and radiochemical purity. For in vivo evaluation, nude mice bearing αvβ3-positive human melanoma M21 and αv-negative human melanoma M21-L or Balb/c mice bearing αv-positive murine osteosarcoma were used. Results: Activity accumulation of 99mTc-DKCK-RGD 240 min p. i. was 1.1% ID/g in the αvβ3-positive melanoma and 0.3% ID/g in the negative control tumour. In the osteosarcoma model 2.2% ID/g was found 240 min p. i. Planar gamma camera images allowed contrasting visualisation of αvβ3-positive tumours 240 min p. i. Blocking of the tumour using the αvβ3-selective pentapeptide cyclo(-ArgGly-Asp-D-Phe-Val-) reduces activity accumulation in the tumour to background level. However, 240 min p. i. highest activity concentration was found in kidneys resulting in low tumour/kidney ratios. Metabolite analysis 240 min p. i. showed approximately 60% intact tracer in kidneys and 80% in the tumour. Only 24% intact tracer was found in blood 30 min p. i. Conclusion: 99mTc-DKCK-RGD allows imaging of αvβ3-positive tumours in mice. However, pharmacokinetics as well as metabolic stability of the tracer have to be improved for potential clinical application.


1983 ◽  
Vol 97 (6) ◽  
pp. 1950-1953 ◽  
Author(s):  
S M Seyedin ◽  
A Y Thompson ◽  
D M Rosen ◽  
K A Piez

An in vitro system has been developed to study the onset of chondrogenesis. Embryonic rat muscle mesenchymal cells, when treated in suspension culture with an extract of bovine bone matrix, synthesized cartilage-specific proteoglycan and type II collagen. The synthesis of these two macromolecules was assayed by the enzyme-linked immunosorbent assay inhibition technique. Further evidence of chondrogenesis was demonstrated by morphological changes of treated cells when cultured in firm agarose and stained for metachromatic matrix. Even with crude bone matrix extracts, the assay was sensitive at the microgram level and significant differences in cartilage macromolecules compared with controls were observed in 2-3 d. In vivo the same extract induced first cartilage and then bone.


1991 ◽  
Vol 252 ◽  
Author(s):  
Sally R. Frenkel ◽  
Ann B. Prewett ◽  
Richard D. Finkelman

Growth and differentiation of animal cells are influenced by a number of interacting local and circulating protein factors. Several such growth factors, or morphogenetic proteins, that affect hard tissue regeneration and repair have been isolated from bone [1–3]. Bone matrix is a complex milieu consisting of serum, cell, and hydroxyapatite binding proteins, bioactive agents, and other proteins whose functions are not yet known. Most of the growth factors can be dissociated from the decalcified collagen matrix only by using chaotropic solvents such as guanidine hydrochloride or urea [4].This extraction removes virtually all noncollagenous proteins from the matrix, producing a nonselective portfolio of proteins, of which growth factors are only a small percentage. A series of chromatographic separations are then required to isolate the morphogenetic proteins from the mixture [5]. Recently, a process has been developed that permits selective extraction of certain growth factors from demineralized bone and produces a water-soluble extract of collagenous and noncollagenous proteins. When placed in an orthotopic site in the rat, the extract exhibits pronounced osteogenic activity and has a surface-adherent property that may be exploited in the coating of allograft bone or osteoprosthetic implants to facilitate osseointegration. The objective of this study is to observe the in vivo effects of this extract on proliferation and synthetic activity of cartilage cells of the chick embryo.


2007 ◽  
Vol 18 (3) ◽  
pp. 179-184 ◽  
Author(s):  
Esther Rieko Takamori ◽  
Eduardo Aleixo Figueira ◽  
Rumio Taga ◽  
Mari Cleide Sogayar ◽  
José Mauro Granjeiro

Treatment of bovine bone with peroxides and chaotropic agents aims to obtain an acellular bone matrix that is able to maintain the collagen-apatite complex and a higher mechanical resistance, a mixed biomaterial hereby named mixed bovine bone (MBB). The purpose of this study was to evaluate the cytocompatibility of MBB and cell-MBB interaction. Cell morphology, number of viable cells, ability to reduce methyltetrazolium and to incorporate neutral red upon exposure to different concentrations of the hydrosoluble extract of MBB were assessed in Balb-c 3T3 cells according to ISO 10993-5 standard. The interaction between cells and MBB surface was evaluated by scanning electron microscopy. The water-soluble MBB extracts were cytotoxic and led to cell death possibly due to its effect on mitochondrial function and membrane permeability. Cells plated directly onto the MBB did not survive, although after dialysis and material conditioning in DMEM + 10% FCS, the cells adhered and proliferated onto the material. It may be concluded that, in vitro, water-soluble MBB extracts were cytotoxic. Nevertheless, MBB cytotoxic effect was reverted by dialysis resulting in a material that is suitable for cell based-therapy in the bioengineering field.


Bone ◽  
2006 ◽  
Vol 38 (1) ◽  
pp. 30-40 ◽  
Author(s):  
Michael Thorwarth ◽  
Falk Wehrhan ◽  
Stefan Schultze-Mosgau ◽  
Jörg Wiltfang ◽  
Karl Andreas Schlegel

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