Friedenstein was the first human to recognize bone-marrow-derived multipotent progenitor stromal cells, also known as Mesenchymal stem cells (MSCs) can be derived from the mammalian periosteum and bone marrow.Bone marrow comprises complex tissues of hematopoietic and stomal sections. The MSCs are found within the complex tissue micro-environment of the stomal division of the bone marrow complex. Those MSCs, which are cultured in vitro, don’t have specific markers. And human MSCs don’t have some hematopoietic markers or co-stimulatory molecules, but they do express some levels of endoglin, transferrin receptors, etc. a study was done to explore the protective effect of Bone Marrow Transplantation (BMT) on the fetal skeleton, secondary to irradiation of the pregnant rats.
Radiation workers are exposed to radiation from different appliances, causing damage to cells and tissues by ionizing them. Ionizing radiation interacts with cells and modifiesthem causing radiation damage that results in the cell due, secondary to the damage to DNA strands. This injured or modified DNA can lead to rapid cell division and genomic instability;thus, radiation is a known mutagen. Embryonic loss and malformations were observed in the mice exposed to gamma radiations. Same exposure during the organogenesis period in pregnancy resulted in organ malformation, stunted growth, mental retardation, microcephaly, and even death in the fetus. These radiations target ossification thus affecting the skull, ribs, vertebrae, and other bones in the body.
Since bone marrow mesenchymal stem cells have the potential to differentiate between different mesenchymal cells, like cartilage, bone, and fat cells, therefore, MSCs can be used for healing injured tissues (cardiac cells, nerve cells, and lunate bone). Transplant of such cells can reduce or prevent oxidative stress by enhancing levels of antioxidants. To study such effects on the fetal skeleton by maternal exposure to radiation, the study was conducted at the Atomic Energy Authority, National Center for Radiation Research and Technology, Egypt.
For the study, Albino rats were selected, transplanted intraperitoneally with the marrow from femur bones after gestation. Separated into 5 groups the gravid rats were exposed to gamma radiations and sacrificed on the 20th day of pregnancy.
The results suggested an abnormal ossification process in skull bones, jaws, metacarpal bones, metatarsal bones in the fetus of rats irradiated with gamma radiations. Some fetuses also showed an absence of ossification centers in the frontal, parietal bones, and all the bones having high porosity. The bone damage could be via a free radical effect on collagen, proving deleterious effects on the bones. For the BMT post-irradiation group, a visible improvement was observed in the bones of jaws, limbs, and skull of the fetus.
The study provides a basis for a deeper understanding of the protective role of bone marrow transplantation, in reducing the hazardous effects of gamma radiations in the fetal skeleton of the rat, who are maternally irradiated in the early days of gestation. It also strengthens the believes that during the pregnancy period, radiation exposure should be prevented. The BMT of MSCs showed promising effects in recovering from gamma radiation exposure.
Bone marrow Transplantation (BMT), Mesenchymal stem cells (MSCs), gamma radiation, bone disorders, DNA damage, oxidative stress, hematopoietic markers, irradiation.