Vitamin A Inhibits Radiation-Induced Pneumonitis in Rats

Abstract

Radiation-induced lung injury frequently limits the total dose of thoracic radiotherapy that can be delivered, and the determinants of host susceptibility are poorly understood. To test the hypothesis that vitamin A status may be an important, modifiable host determinant of radiation-induced lung injury, we determined the effect of altered vitamin A status on radiation-induced lung inflammation in rats. WAG-Rij Y rats were fed a diet deficient in or supplemented with vitamin A (0 units/kg or 80,000 units/kg diet). After 5 wk of consuming the prescribed diet, rats were irradiated with 15 Gy of 250 kV X-rays to the whole thorax. At 4-5 wk post-irradiation, there were significantly fewer neutrophils on bronchoalveolar lavage in rats fed the vitamin A-supplemented diet (8.8 +/- 1.2% neutrophils) compared with those fed the vitamin A-deficient diet (20.8 +/- 3.4% neutrophils, P < 0.01). At the termination of the experiment, 4-5 wk postradiation, lung retinol levels of the vitamin A-supplemented group were 19.6 +/- 1.8 nmol/g, whereas those in the vitamin A-deficient group were significantly lower, 1.7 +/- 0.5 nmol/g (P < 0.01). These findings suggest that supplemental vitamin A may reduce lung inflammation after thoracic radiation and be an important modifiable radioprotective agent in the lung.

Vitamin A levels in patients with CF are influenced by the inflammatory response

“…Acute inflammation causes a reduction in serum vitamin A, ascribed to a reduction in the hepatic synthesis of retinol binding protein, and reduction in secretion of the retinol -retinol binding protein complex [6,9,10]. Conversely, animal studies have shown a protective effect of both retinol (vitamin A) and hcarotene supplementation against the inflammatory response [11,12]. Vitamin A deficiency causes night blindness and xerophthalmia, and is the leading cause of childhood blindness in developing countries [13].…”

Transforming Growth Factor-β Stimulates Interleukin-11 Transcription via Complex Activating Protein-1-dependent Pathways

“…Among its many effects are the ability to regulate hematopoiesis, stimulate the production of acute phase proteins, induce the tissue inhibitor of metalloproteinase-1, regulate bone metabolism, and alter epithelial proliferation (2, 6 -10). Studies from our laboratories and others have also demonstrated that IL-11 can induce tissue fibrosis, regulate tissue myocyte and myofibroblast accumulation, alter airway physiology, and confer protection in the context of mucosal injury of the respiratory and gastrointestinal tracts (11)(12)(13)(14).…”

Palliative effects of lutein intervention in gamma-radiation-induced cellular damages in Swiss albino mice

“…[15] In the present study, lutein has been evaluated as a radioprotector against gamma radiation-induced biochemical changes although lutein has been shown to be a moderate antioxidant in vitro in the previous studies. [16]…”