Research Article

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

Figure 7

Repetitive HBOT downregulates CD40L expression after CSI. (a) Immunoblot analysis showed that CD40L was present as a single band with a molecular mass of about 36 kDa. After CSI expression of CD40L significantly () increased in respect to intact control (C) and sham-operated animals (S). However, compared to L group in LHBO group statistically significant reduction () of CD40L protein expression was observed. Bars represent mean ± SEM of CD40L protein content (relative to β-actin). Samples are from 4 animals per each group. Dot line represents mean of CD40L 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. ((b) and (c)) In control cortex CD40L was localized in blood vessels ((c) asterisk). (d) At 10th day after CSI intense CD40L immunoreactivity occurred in perilesioned area: ((d), inset) in macrophages/microglia and neutrophils and (e) in protoplasmic astrocytes in close contact with endothelial cells via astrocytic end-feet (asterisk). (f) Repetitive HBOT decreased CD40L immunostaining in the injured cortex. (g) CD40L-positive astrocytes had fibrous form. Rectangles indicate where the high magnification images are taken from. Scale bar = 50 μm.