A preclinical model for radio-osteoporosis induction


Por: Ramírez E.H., Martínez F.H., Bello J.S., Medina L.A.

Publicada: 1 ene 2021
Categoría: Physics and astronomy (miscellaneous)

Resumen:
Bone is one of the most affected tissue during radiation therapy treatments. In postmenopausal women, the risk of a hip and femoral head fracture due to osteoporosis induced by ionizing radiation increases from 65% to 216% after receiving radiation treatment for cervical, anal, or rectal cancer. To date, there is no preventive or curative treatment for this damage; this situation promotes to explore preclinical models of radio-osteoporosis. In this work, the pelvic region of adult (male and female) Wistar rats were irradiated with a 6 MV photon beam. Four schemes of two fractions (2 fx) and one scheme of four fractions (4 fx), all with different fractional doses, were evaluated. microCT images were acquired two and four months after irradiations to evaluate changes in the hydroxyapatite concentration [HA] in the hip and femoral head. After imaging, animals were sacrificed, and the femurs were removed to perform histology and scanning electron microscopy studies to evaluate changes in trabecular bone microarchitecture. Low [HA] in the femoral head was observed in male rats (30-weeks-old) after two months post-irradiations. In the hip, a reduction of [HA] was observed after four months. No significant changes were detected in the bone microarchitecture. In female rats, no significant differences (experimental vs. control) in [HA] were observed. This result was associated with the age of rats (12-week-old) at the time of irradiations; it is known that the repair of radiation damage in bone tissue is more efficient in younger rats than in older rats. Visual inspection in the shape of the microarchitecture shows structural differences in the irradiated group; however, quantitative differences in the parameters of the evaluation were not detected. The fractionation schemes of irradiation implemented in this work result in bone damage that could promote radio-osteoporosis. Work is in progress with different image analysis techniques to quantify the damage in the microarchitecture. © 2021 American Institute of Physics Inc.. All rights reserved.

Filiaciones:
Ramírez E.H.:
 Posgrado en Ciencias Físicas, UNAM, Ciudad de México, Mexico

 Instituto de Física, UNAM, Ciudad de México, Mexico

Martínez F.H.:
 Departamento de Radioterapia, Instituto Nacional de Cancerología, Ciudad de México, Mexico

Bello J.S.:
 Laboratorio de Bioingeniería de Tejidos, Facultad de Odontología UNAM, Ciudad de México, Mexico

Medina L.A.:
 Instituto de Física, UNAM, Ciudad de México, Mexico

 Unidad de Investigación Biomédica en Cáncer, INCan/UNAM, Ciudad de México, Mexico
ISSN: 0094243X
Editorial
AMER INST PHYSICS, 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA, Estados Unidos America
Tipo de documento: Conference Paper
Volumen: 2348 Número:
Páginas:
imagen Bronze