Assessment of bone matrix composition in teleost fish and humans using Raman spectroscopy

Introduction

Bony fish (i.e. teleosts) are emerging small-sized animal models to investigate bone quality, metabolism, and disease pathomechanisms. In particular, species as the swordfish (Xiphias gladius) [1] and killifish (Nothobranchius furzeri) [2] have been recently introduced to the musculoskeletal disciplines because of their peculiar hard tissue biology. We carried out a comprehensive ex vivo analysis of bone tissue to compare the hard tissue properties of the swordfish rostrum, and the killifish vertebral bone with human bone tissue. This macromolecular study of the tissue composition reveals species-dependent similarities and differences in tissue composition.

Material & Methods

Bone matrix composition of killifish (n=3), swordfish rostrum (n=3) and humans (n=6) were analyzed using Raman spectroscopy. Spectra were collected with the scan range from 400 to 1800 cm-1 . Twenty bone spectra/sample were baseline-subtracted and averaged. Mineral-to-matrix ratios (MMR) were calculated: v1PO4 (930–980 cm-1)/amide I (1620–1700 cm1), v1PO4/amide III (1215–1300 cm-1) and carbonate-to-phosphate ratio (CPR) CO3(1050–1100 cm-1)/v1PO4 [3].

Results

Both MMRs did not differ between swordfish and human samples (p>0.05 for both) but were significantly different between killifish and the other two groups (pswordfish0.05 for both).

Conclusion

Differences in mineral composition in the studied species were evident. Low CPR in both fish was found in comparison to human bone. The low CPR may be linked to differences in mineral metabolism required in the aquatic environments. Generally, our results point towards the presence of the same macromolecular components including phosphate, carbonate, amide I, and amide III in all bone types. Further studies will help to better understand the width of hard tissue properties contributing to individual bone quality characteristics across species.

Conflict of Interest

The authors declare no conflict of interest.

• References

• 1 Schmidt et al. Adv. Sci. 2019 vol. 6, no. 12, p. 1900287, doi: 10.1002/advs.201900287
• 2 Poeschla et al. J. Exp. Biol. 2020, vol. 223, no. Suppl_1, p. jeb209296, doi: 10.1242/jeb.209296
• 3 Gamsjaeger et al. Bone 2010. vol. 47, no. 2, pp. 392–399, doi: 10.1016/ j.bone.2010.04.608

Publication History

Article published online:
04 November 2021