The dose limiting toxicities of Ionizing Radiation (IR) in radiosensitive normal tissues, such as bone marrow, intestine, and skin, precludes the delivery of curative or effective palliative doses of radiation in many cases. Despite of the intense research effort in the past to find new effective and well-tolerated radioprotectors, only one drug has been approved by FDA for this indication. One...

Studies of radioresistance and radioprotection provide an excellent in vivo model for dissection of the pathophysiological role of cytokines. The availability of neutralizing antibodies to cytokines has made it possible to assess the contribution of cytokines to host defense and repair processes involved in radioresistance and radioprotection. Administration of anti-interleukin 1 receptor (IL-1...

With the goal to enhance the distribution of cationic Mn porphyrins within mitochondria, the lipophilic Mn(III)meso-tetrakis(N-n-hexylpyridinium-2-yl)porphyrin, MnTnHex-2-PyP(5+) has been synthesized and tested in several different model of diseases, where it shows remarkable efficacy at as low as 50 µg/kg single or multiple doses. Yet, in a rat lung radioprotection study, at higher 0.6-1 mg/kg...

The development of a system capable of ensuring adequate protection of the environment from the harmful effects of ionising radiation is at present particularly debated. This need comes both from a restrictive consideration of the environment in the so far existing system for human radioprotection, and the planetary-wide growing concerns about man's technogenic influence on his environment whic...

Hematopoietic stem cells (HSCs) are defined in mice by three activities: they must rescue lethally irradiated mice (radioprotection), they must self-renew, and they must restore all blood cell lineages permanently. We initially demonstrated that HSCs were contained in a rare ('~0.05%) subset of bone marrow cells with the following surface marker profile: Thy-l.1 l~ LinSca-l+. These cells were c...

Hematopoietic stem cells (HSCs) are defined in mice by three activities: they must rescue lethally irradiated mice (radioprotection), they must self-renew, and they must restore all blood cell lineages permanently. We initially demonstrated that HSCs were contained in a rare ('~0.05%) subset of bone marrow cells with the following surface marker profile: Thy-l.1 l~ LinSca-l+. These cells were c...

Hematopoietic stem cells (HSCs) are defined in mice by three activities: they must rescue lethally irradiated mice (radioprotection), they must self-renew, and they must restore all blood cell lineages permanently. We initially demonstrated that HSCs were contained in a rare (approximately 0.05%) subset of bone marrow cells with the following surface marker profile: Thy-1.1lo Lin- Sca-1+. These...

It was previously shown on heat shock protein (Hsp)-overexpressing cell lines that the increased intracellular content of Hsp70 or Hsp27 is associated with the elevated radioresistance. However, it was so far unknown whether the in vivo Hsp induction by stressful preconditioning can confer radioprotection at the tissue and cellular levels. In the present study, we examined how the in vivo up-re...