Osteoinductive nanohydroxyapatite bone substitute prepared via in situ hydrothermal transformation of cuttlefish bone

Cuttlefish-Bone-Derived Biomaterials in Regenerative Medicine, Dentistry, and Tissue Engineering: A Systematic Review

BACKGROUND

Marine ecosystems, covering 70% of Earth's surface, hold immense biodiversity and potential for biomaterials. Cuttlefish bone (CB) and marine resources have gained attention as eco-friendly biomaterials.

OBJECTIVES

We aim to comprehensively study biomedical applications of CB-derived materials. By evaluating both in vivo and in vitro investigations, the review seeks to uncover the diverse potential of CB in the biomedical field.

METHODS

A comprehensive search of electronic databases yielded 51 articles from 2408 studies. These studies encompassed in vivo animal studies and in vitro investigations.

RESULTS

In vivo studies employed for bone repair, dorsal subcutaneous defects, thermal wound healing, muscle injections, and avian blood testing. In vitro studies focused on HAp synthesis, scaffold development, dental material enhancement, and antimicrobial properties. Risk of bias assessments revealed varying degrees of methodological quality in both animal and in vitro studies, underscoring the need for standardised reporting and rigorous study design in future research.

CONCLUSIONS

This review fills a gap in the literature by providing a comprehensive overview of the applications of CB-derived materials in the biomedical field. Additionally, it offers valuable insights for researchers, clinicians, and policymakers interested in sustainable and effective biomaterials for diverse medical purposes, advancing the fields of regenerative medicine and dentistry.

The Association of Nanostructured Carbonated Hydroxyapatite with Denatured Albumin and Platelet-Rich Fibrin: Impacts on Growth Factors Release and Osteoblast Behavior

Platelet-rich Fibrin (PRF), a second-generation blood concentrate, offers a versatile structure for bone regeneration due to its composition of fibrin, growth factors, and cytokines, with adaptations like denatured albumin-enriched with liquid PRF (Alb-PRF), showing potential for enhanced stability and growth factor dynamics. Researchers have also explored the combination of PRF with other biomaterials, aiming to create a three-dimensional framework for enhanced cell recruitment, proliferation, and differentiation in bone repair studies. This study aimed to evaluate a combination of Alb-PRF with nanostructured carbonated hydroxyapatite microspheres (Alb-ncHA-PRF), and how this association affects the release capacity of growth factors and immunomodulatory molecules, and its impact on the behavior of MG63 human osteoblast-like cells. Alb-PRF membranes were prepared and associated with nanocarboapatite (ncHA) microspheres during polymerization. MG63 cells were exposed to eluates of both membranes to assess cell viability, proliferation, mineralization, and alkaline phosphatase (ALP) activity. The ultrastructural analysis has shown that the spheres were shattered, and fragments were incorporated into both the fibrin mesh and the albumin gel of Alb-PRF. Alb-ncHA-PRF presented a reduced release of growth factors and cytokines when compared to Alb-PRF (p < 0.05). Alb-ncHA-PRF was able to stimulate osteoblast proliferation and ALP activity at lower levels than those observed by Alb-PRF and was unable to positively affect in vitro mineralization by MG63 cells. These findings indicate that the addition of ncHA spheres reduces the biological activity of Alb-PRF, impairing its initial effects on osteoblast behavior.

The Use of Shells of Marine Molluscs in Spanish Ethnomedicine: A Historical Approach and Present and Future Perspectives

Since ancient times, the shells of marine molluscs have been used as a therapeutic and/or prophylactic resource. In Spain, they were part of practical guides for doctors or pharmacists until the 19th century. In general, seashells were prepared by dissolving in vinegar and were part of plasters or powders used as toothpaste, or to treat dyspepsia, heartburn and leprosy. Thus, the nacre or mother-of-pearl of various molluscs was regularly used in the Royal Colleges of Surgery and in hospitals during the times of the Cortes of Cadiz, as a medicine in galenic preparations based on powders. In contemporary Spanish ethnomedicine, seashells, with a high symbolic value, have been used as an amulet to prevent cracks in the breasts and promote their development during lactation, to avoid teething pain in young children, to eliminate stains on the face or to cure erysipelas. But, as in other countries, products derived from seashells have also been empirically applied. The two resources used traditionally have been the cuttlebone, the internal shell of cuttlefish and the nacre obtained from the external shells of some species. Cuttlebone, dried and pulverised, has been applied externally to cure corneal leukoma and in dental hygiene. In the case of nacre, a distinction must be made between chemical and physical remedies. Certain seashells, macerated in lemon juice, were used in coastal areas to remove spots on the face during postpartum. However, the most common practice in Spain mainland was to dissolve mother-of-pearl buttons in lemon juice (or vinegar). The substance thus obtained has been used to treat different dermatological conditions of the face (chloasma, acne), as well as to eliminate freckles. For the extraction of foreign bodies in the eyes, a very widespread traditional remedy has been to introduce small mother-of-pearl buttons under the lid. These popular remedies and practices are compared with those collected in classic works of medicine throughout history, and data on the pharmacological activity and pharmaceutical applications of the products used are provided. The use of cuttlebone powders is supported by different works on anti-inflammatory, immune-modulatory and/or wound healing properties. Nacre powder has been used in traditional medicines to treat palpitations, convulsions or epilepsy. As sedation and a tranquilisation agent, nacre is an interesting source for further drug development. Likewise, nacre is a biomaterial for orthopaedic and other tissue bioengineering applications. This article is a historical, cultural and anthropological view that can open new epistemological paths in marine-derived product research.

The Stimulation of Macrophages by Systematical Administration of GM-CSF Can Accelerate Adult Wound Healing Process

Skin wound repair remains a major challenge in clinical care, and various strategies have been employed to improve the repair process. Recently, it has been reported that macrophages are important for the regeneration of various tissues and organs. However, their influence on wound repair is unclear. Here, we aimed to explore whether macrophages would participate in the wound healing process and to explore new possibilities of treatment for skin defects. We firstly created a mouse full-thickness skin defect model to observe the distribution of macrophages in the regenerating tissue and then detected the influence of macrophages on skin defect repair in both macrophage-depletion and macrophage-mobilization models. We found that the number of macrophages increased significantly after skin defect and persisted during the process of wound repair. The regeneration process was significantly prolonged in macrophage-depleted animals. RT-qPCR and ELISA assays further demonstrated that the expression of growth factors was perturbed in the regenerating tissue. The activation of macrophages by granulocyte-macrophage colony-stimulating factor (GM-CSF) injection could significantly improve wound healing, accompanied with an upregulation of the expression of various growth factors. In conclusion, the current study demonstrated that macrophages are critical for skin regeneration and that GM-CSF exhibited therapeutic potential for wound healing.

Highly Porous Composite Scaffolds Endowed with Antibacterial Activity for Multifunctional Grafts in Bone Repair

The present study deals with the development of multifunctional biphasic calcium phosphate (BCP) scaffolds coated with biopolymers—poly(ε-caprolactone) (PCL) or poly(ester urea) (PEU)—loaded with an antibiotic drug, Rifampicin (RFP). The amounts of RFP incorporated into the PCL and PEU-coated scaffolds were 0.55 ± 0.04 and 0.45 ± 0.02 wt%, respectively. The in vitro drug release profiles in phosphate buffered saline over 6 days were characterized by a burst release within the first 8h, followed by a sustained release. The Korsmeyer–Peppas model showed that RFP release was controlled by polymer-specific non-Fickian diffusion. A faster burst release (67.33 ± 1.48%) was observed for the PCL-coated samples, in comparison to that measured (47.23 ± 0.31%) for the PEU-coated samples. The growth inhibitory activity against Escherichia coli and Staphylococcus aureus was evaluated. Although the RFP-loaded scaffolds were effective in reducing bacterial growth for both strains, their effectiveness depends on the particular bacterial strain, as well as on the type of polymer coating, since it rules the drug release behavior. The low antibacterial activity demonstrated by the BCP-PEU-RFP scaffold against E. coli could be a consequence of the lower amount of RFP that is released from this scaffold, when compared with BCP-PCL-RFP. In vitro studies showed excellent cytocompatibility, adherence, and proliferation of human mesenchymal stem cells on the BCP-PEU-RFP scaffold surface. The fabricated highly porous scaffolds that could act as an antibiotic delivery system have great potential for applications in bone regeneration and tissue engineering, while preventing bacterial infections.

Biomaterials from the sea: Future building blocks for biomedical applications

Marine resources have tremendous potential for developing high-value biomaterials. The last decade has seen an increasing number of biomaterials that originate from marine organisms. This field is rapidly evolving. Marine biomaterials experience several periods of discovery and development ranging from coralline bone graft to polysaccharide-based biomaterials. The latter are represented by chitin and chitosan, marine-derived collagen, and composites of different organisms of marine origin. The diversity of marine natural products, their properties and applications are discussed thoroughly in the present review. These materials are easily available and possess excellent biocompatibility, biodegradability and potent bioactive characteristics. Important applications of marine biomaterials include medical applications, antimicrobial agents, drug delivery agents, anticoagulants, rehabilitation of diseases such as cardiovascular diseases, bone diseases and diabetes, as well as comestible, cosmetic and industrial applications.

[Study on tailoring the nanostructured surfaces of cuttlefish bone transformed hydroxyapatite porous ceramics and its effect on osteoblasts]

Objective

To investigate the formation of nanostructure on cuttlefish bone transformed hydroxyapatite (CB-HA) porous ceramics and the effects of different nanostructures on the osteoblasts adhesion, proliferation, and alkaline phosphatase (ALP) expression.

Methods

The cuttlefish bone was shaped as plate with diameter of 10 mm and thickness of 2 mm, filled with water, and divided into 4 groups. The CB-HA in groups 1-4 were mixed with different phosphorous solutions and then placed in an oven at 120℃ for 24 hours. In addition, the samples in group 4 were further sintered at 1 200℃ for 3 hours to remove nanostructure as controls. The chemical composition of CB-HA were analyzed by X-ray diffraction spectroscopy, Fourier transform infrared spectrum, and inductively coupled plasma (ICP). The physical structure was analyzed using scanning electron microscopy, specific surface tester, and porosity tester. The MC3T3-E1 cells of 4th generation were co-cultured with 4 groups of CB-HA. After 1 day, the morphology of the cells was observed under scanning electron microscopy. After 1, 3, and 7 days, the cell proliferation was analyzed by MTT assay. After 7 and 14 days, the ALP expression was measured by pNPP method.

Results

X-ray diffraction spectrum showed that the four nanostructures of CB-HA were made of hydroxyapatite. The infrared absorption spectrum showed that the infrared absorption peak of CB-HA was consistent with hydroxyapatite. ICP showed that the ratio of calcium to phosphorus of all CB-HA was 1.68-1.76, which was consistent with hydroxyapatite. Scanning electron microscopy observation showed that the nanostructure on the surface of CB-HA in groups 1-3 were large, medium, and small cluster-like structures, respectively, and CB-HA in group 4 had no obvious nanostructure. There were significant differences in the specific surface areas between groups ( P<0.05). There was no significant difference in the porosity between groups ( P>0.05). Compared with group 4, groups 1-3 have more pores with pore size less than 50 nm. After co-cultured with osteoblasts, scanning electron microscopy observation and MTT assay showed that the cells on groups 2 and 3 adhered and proliferated better and had more ALP expression than that on groups 1 and 4 ( P<0.05).

Conclusion

The size of cluster-like nanostructure on the surface of CB-HA can be controlled by adjusting the concentration of ammonium ions in the phosphorous solution, and the introduction of small-sized cluster-like nanostructure on the surface of CB-HA can significantly improve the cell adhesion, proliferation, and ALP expression of the material which might be resulted from the enlarged surface area.

Synthetic and Marine-Derived Porous Scaffolds for Bone Tissue Engineering

Bone is a vascularized and connective tissue. The cortical bone is the main part responsible for the support and protection of the remaining systems and organs of the body. The trabecular spongy bone serves as the storage of ions and bone marrow. As a dynamic tissue, bone is in a constant remodelling process to adapt to the mechanical demands and to repair small lesions that may occur. Nevertheless, due to the increased incidence of bone disorders, the need for bone grafts has been growing over the past decades and the development of an ideal bone graft with optimal properties remains a clinical challenge. This review addresses the bone properties (morphology, composition, and their repair and regeneration capacity) and puts the focus on the potential strategies for developing bone repair and regeneration materials. It describes the requirements for designing a suitable scaffold material, types of materials (polymers, ceramics, and composites), and techniques to obtain the porous structures (additive manufacturing techniques like robocasting or derived from marine skeletons) for bone tissue engineering applications. Overall, the main objective of this review is to gather the knowledge on the materials and methods used for the production of scaffolds for bone tissue engineering and to highlight the potential of natural porous structures such as marine skeletons as promising alternative bone graft substitute materials without any further mineralogical changes, or after partial or total transformation into calcium phosphate.

Laminated electrospun nHA/PHB-composite scaffolds mimicking bone extracellular matrix for bone tissue engineering

Electrospinning is an effective means to generate nano- to micro-scale polymer fibers resembling native extracellular matrix for tissue engineering. However, a major problem of electrospun materials is that limited pore size and porosity may prevent adequate cellular infiltration and tissue ingrowth. In this study, we first prepared thin layers of hydroxyapatite nanoparticle (nHA)/poly-hydroxybutyrate (PHB) via electrospinning. We then laminated the nHA/PHB thin layers to obtain a scaffold for cell seeding and bone tissue engineering. The results demonstrated that the laminated scaffold possessed optimized cell-loading capacity. Bone marrow mesenchymal stem cells (MSCs) exhibited better adherence, proliferation and osteogenic phenotypes on nHA/PHB scaffolds than on PHB scaffolds. Thereafter, we seeded MSCs onto nHA/PHB scaffolds to fabricate bone grafts. Histological observation showed osteoid tissue formation throughout the scaffold, with most of the scaffold absorbed in the specimens 2months after implantation, and blood vessels ingrowth into the graft could be observed in the graft. We concluded that electrospun and laminated nanoscaled biocomposite scaffolds hold great therapeutic potential for bone regeneration.