Repetitive long-term hyperbaric oxygen treatment (HBOT) administered after experimental traumatic brain injury in rats induces significant remyelination and a recovery of sensorimotor function.

Cells in the central nervous system rely almost exclusively on aerobic metabolism. Oxygen deprivation, such as injury-associated ischemia, results in detrimental apoptotic and necrotic cell loss. There is evidence that repetitive hyperbaric oxygen therapy (HBOT) improves outcomes in traumatic brain-injured patients. However, there are no experimental studies investigating the mechanism of repetitive long-term HBOT treatment-associated protective effects. We have therefore analysed the effect of long-term repetitive HBOT treatment on brain trauma-associated cerebral modulations using the lateral fluid percussion model for rats. Trauma-associated neurological impairment regressed significantly in the group of HBO-treated animals within three weeks post trauma. Evaluation of somatosensory-evoked potentials indicated a possible remyelination of neurons in the injured hemisphere following HBOT. This presumption was confirmed by a pronounced increase in myelin basic protein isoforms, PLP expression as well as an increase in myelin following three weeks of repetitive HBO treatment. Our results indicate that protective long-term HBOT effects following brain injury is mediated by a pronounced remyelination in the ipsilateral injured cortex as substantiated by the associated recovery of sensorimotor function.

Remission of endometriosis by hyperbaric oxygen treatment in rats.

We designed this prospective, randomized controlled animal study to determine the effects of hyperbaric oxygen (HBO) on experimentally induced endometriosis in a rat model. Surgical induction of endometriosis was performed in 40, nonpregnant, female, Wistar-Albino rats at the Experimental Medicine Research Center of Istanbul University (DETAE). Four weeks later, the first and second laparotomies for volume measurement and peritoneal fluid (PF) collection were performed, and the rats were divided randomly into the study and control groups. The study group was exposed to HBO treatment for 6 weeks. Then, a third laparotomy was performed on all of the rats. The volume, histopathologic scores, Ki-67 labeling of the endometriotic implants, and the levels of tumor necrosis factor-α (TNF-α) in the PF were measured. The mean volume of the endometriotic implants in the study group was significantly lower than that of the control group at the end of the study (57.4 ± 12.5 vs 94.6 ± 17.2 mm(3)). The mean histopathological scores (1.60 ± 0.50 vs 2.42 ± 0.51), Ki-67 immunohistochemical scores (1.50 ± 0.51 vs 2.37 ± 0.49) of the endometriotic implants, and the TNF-α levels (5.33 ± 1.02 vs 8.16 ± 1.76 pg/mL) were significantly lower in the study group than in the control group. Hyperbaric oxygen treatment for 2 hours a day for 6 weeks resulted in significant remission of endometriosis in rats.