Use of an agent that restores tissue perfusion and oxygenation
The presently disclosed subject matter provides methods for increasing perfusion in hypoxic regions of tissues in subjects. Also provided are methods for treating diseases and/or disorders associated with hypoxia in subjects, methods for increasing sensitivity of tumors to radiation and/or chemotherapy treatments, methods for delaying tumor growth in subjects, and methods for inhibiting tumor blood vessel growth in subjects. In some embodiments, the presently disclosed methods involve administering to subjects in need thereof a first composition selected from the group consisting of a nitrosylated hemoglobin and an agent that induces nitrosylation of endogenous hemoglobin in the subject and a second composition comprising a hyperoxic gas. In some embodiments, the presently disclosed methods also include treating a tumor with radiation therapy, chemotherapy, photodynamic therapy, immunotherapy, or combinations thereof. Also provided are inhalable gases that can be employed in the presently disclosed methods.
1. A method of increasing perfusion in a hypoxic region of a cancer tissue or tumor in a subject, the method comprising administering to the subject:
(a) a composition comprising an agent that induces nitrosylation of hemoglobin in the subject; and
(b) a hyperoxic gas.
2. The method of claim 1 , wherein the agent that induces nitrosylation of hemoglobin in the subject comprises ethyl nitrite (ENO).
3. The method of claim 2 , wherein the ethyl nitrite (ENO) is administered to the subject as an inhalable composition comprising about 100 parts per million (ppm) in the hyperoxic gas.
4. The method of claim 1 , wherein the hemoglobin is present within a red blood cell.
5. The method of claim 4 , wherein the red blood cell is present within the subject.
6. The method of claim 1 , wherein the hyperoxic gas is selected from the group consisting of pure oxygen and carbogen.
7. The method of claim 1 , wherein the subject is a mammal.
8. The method of claim 7 , wherein the mammal is a human.
9. The method of claim 1 , wherein the administering results increases a pO 2 value in at least a fraction of the hypoxic region of the tissue to at least about 10 mm Hg.
10. The method of claim 1 , wherein the administering ameliorates at least one symptom associated said cancer or said tumor in the subject.