Repetitive Hyperbaric Oxygenation Attenuates Reactive Astrogliosis and Suppresses Expression of Inflammatory Mediators in the Rat Model of Brain Injury

Figure 2

Repetitive HBOT reduces gene and tissue expression of vimentin after CSI. Upregulation of vimentin expression both at mRNA (a) and protein (b) levels is observed after CSI in the injured cortex compared to intact control and sham-operated animals. (a) Repetitive HBOT reduced levels of vimentin mRNA to those detected in control groups. Bars represent mean ± SEM of vimentin mRNA (relative to GAPDH). (b) Immunoblot analysis showed that vimentin was present as a single band with a molecular mass of about 57 kDa. HBOT slightly but not statistically significantly decreased vimentin expression. Bars represent mean ± SEM of vimentin protein content (relative to β-actin). Samples are from 4 animals per each group. Dot line represents mean of vimentin mRNA or protein level ± SEM (gray area) measured in control animals. Letters indicate significance levels () between lesioned (L) and intact control groups, L versus sham control (S) group, and L compared to lesioned group subjected to the HBO protocol (LHBO). The groups not sharing a common letter are statistically different. Level of significance was analyzed using Student’s -test. (c) The luminosity of glial scar is obtained by measuring vimentin staining intensity around the lesion site and presented on histogram. ((d) and (e)) Vimentin immunoreactivity was negligible in the cortex of intact rats. ((f) and (g)) After CSI vimentin staining was significantly increased in the proximity to the lesion site. Vimentin⁺ astrocytes had enlarged cell bodies with thick processes. ((h) and (i)) After HBOT reactive astrocytes surrounded the lesion site as a narrow line. Rectangles indicate where the high magnification images are taken from. Scale bar = 50 μm.