Limits...
Repetitive hyperbaric oxygenation attenuates reactive astrogliosis and suppresses expression of inflammatory mediators in the rat model of brain injury.

Lavrnja I, Parabucki A, Brkic P, Jovanovic T, Dacic S, Savic D, Pantic I, Stojiljkovic M, Pekovic S - Mediators Inflamm. (2015)

Bottom Line: The exact mechanisms by which treatment with hyperbaric oxygen (HBOT) exerts its beneficial effects on recovery after brain injury are still unrevealed.Data obtained using real-time polymerase chain reaction, Western blot, and immunohistochemical and immunofluorescence analyses revealed that repetitive HBOT applied after the CSI attenuates reactive astrogliosis and glial scarring, and reduces expression of GFAP (glial fibrillary acidic protein), vimentin, and ICAM-1 (intercellular adhesion molecule-1) both at gene and tissue levels.Accordingly, repetitive HBOT, by prevention of glial scarring and limiting of expression of inflammatory mediators, supports formation of more permissive environment for repair and regeneration.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurobiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, 11060 Belgrade, Serbia.

ABSTRACT
The exact mechanisms by which treatment with hyperbaric oxygen (HBOT) exerts its beneficial effects on recovery after brain injury are still unrevealed. Therefore, in this study we investigated the influence of repetitive HBOT on the reactive astrogliosis and expression of mediators of inflammation after cortical stab injury (CSI). CSI was performed on male Wistar rats, divided into control, sham, and lesioned groups with appropriate HBO. The HBOT protocol was as follows: 10 minutes of slow compression, 2.5 atmospheres absolute (ATA) for 60 minutes, and 10 minutes of slow decompression, once a day for 10 consecutive days. Data obtained using real-time polymerase chain reaction, Western blot, and immunohistochemical and immunofluorescence analyses revealed that repetitive HBOT applied after the CSI attenuates reactive astrogliosis and glial scarring, and reduces expression of GFAP (glial fibrillary acidic protein), vimentin, and ICAM-1 (intercellular adhesion molecule-1) both at gene and tissue levels. In addition, HBOT prevents expression of CD40 and its ligand CD40L on microglia, neutrophils, cortical neurons, and reactive astrocytes. Accordingly, repetitive HBOT, by prevention of glial scarring and limiting of expression of inflammatory mediators, supports formation of more permissive environment for repair and regeneration.

No MeSH data available.


Related in: MedlinePlus

Effect of repetitive HBOT on GFAP expression after CSI. CSI provoked upregulation of GFAP expression both at mRNA (a) and protein (b) levels in the injured cortex compared to intact control and sham-operated animals, while repetitive HBOT reduced levels of GFAP mRNA to those detected in control groups. (a) Bars represent mean ± SEM of GFAP mRNA (relative to GAPDH). (b) Immunoblot analysis showed that GFAP was present as a single band with a molecular mass of about 50 kDa. Bars represent mean ± SEM of GFAP protein content (relative to β-actin). Samples are from 4 animals per each group. Dot line represents mean of GFAP mRNA or protein level ± SEM (gray area) measured in control animals. Letters indicate significance levels (P < 0.005) between lesioned (L) and intact control group, 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 t-test. (c) The luminosity of glial scar is obtained by measuring GFAP staining intensity around the lesion site and presented on histogram. ((d) and (e)) Throughout the cortex of intact rats a small number of fibrous GFAP+ astrocytes is seen. ((f) and (g)) At 10 days after injury a huge number of reactive astrocytes with pronounced hypertrophy of cell body and processes ((g) inset) form glial scar around the lesion site. ((h) and (i)) Ten successive HBOT significantly reduced glial scar formation, and the majority of astrocytes attained fibrous morphology ((i) inset). Rectangles indicate where the high magnification images are taken from. Scale bar = 50 μm.
© Copyright Policy - open-access
Related In: Results  -  Collection


getmorefigures.php?uid=PMC4417949&req=5

fig1: Effect of repetitive HBOT on GFAP expression after CSI. CSI provoked upregulation of GFAP expression both at mRNA (a) and protein (b) levels in the injured cortex compared to intact control and sham-operated animals, while repetitive HBOT reduced levels of GFAP mRNA to those detected in control groups. (a) Bars represent mean ± SEM of GFAP mRNA (relative to GAPDH). (b) Immunoblot analysis showed that GFAP was present as a single band with a molecular mass of about 50 kDa. Bars represent mean ± SEM of GFAP protein content (relative to β-actin). Samples are from 4 animals per each group. Dot line represents mean of GFAP mRNA or protein level ± SEM (gray area) measured in control animals. Letters indicate significance levels (P < 0.005) between lesioned (L) and intact control group, 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 t-test. (c) The luminosity of glial scar is obtained by measuring GFAP staining intensity around the lesion site and presented on histogram. ((d) and (e)) Throughout the cortex of intact rats a small number of fibrous GFAP+ astrocytes is seen. ((f) and (g)) At 10 days after injury a huge number of reactive astrocytes with pronounced hypertrophy of cell body and processes ((g) inset) form glial scar around the lesion site. ((h) and (i)) Ten successive HBOT significantly reduced glial scar formation, and the majority of astrocytes attained fibrous morphology ((i) inset). Rectangles indicate where the high magnification images are taken from. Scale bar = 50 μm.

Mentions: Real-time PCR analysis was used to evaluate the effect of HBOT and CSI on GFAP gene expression. After CSI, the mRNA level of GFAP was increased 4-fold (P < 0.005) in the injured cortex with respect to intact control and sham-operated animals. In contrast, repetitive HBOT induced downregulation of GFAP mRNA expression to levels detected in control groups (Figure 1(a)).


Repetitive hyperbaric oxygenation attenuates reactive astrogliosis and suppresses expression of inflammatory mediators in the rat model of brain injury.

Lavrnja I, Parabucki A, Brkic P, Jovanovic T, Dacic S, Savic D, Pantic I, Stojiljkovic M, Pekovic S - Mediators Inflamm. (2015)

Effect of repetitive HBOT on GFAP expression after CSI. CSI provoked upregulation of GFAP expression both at mRNA (a) and protein (b) levels in the injured cortex compared to intact control and sham-operated animals, while repetitive HBOT reduced levels of GFAP mRNA to those detected in control groups. (a) Bars represent mean ± SEM of GFAP mRNA (relative to GAPDH). (b) Immunoblot analysis showed that GFAP was present as a single band with a molecular mass of about 50 kDa. Bars represent mean ± SEM of GFAP protein content (relative to β-actin). Samples are from 4 animals per each group. Dot line represents mean of GFAP mRNA or protein level ± SEM (gray area) measured in control animals. Letters indicate significance levels (P < 0.005) between lesioned (L) and intact control group, 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 t-test. (c) The luminosity of glial scar is obtained by measuring GFAP staining intensity around the lesion site and presented on histogram. ((d) and (e)) Throughout the cortex of intact rats a small number of fibrous GFAP+ astrocytes is seen. ((f) and (g)) At 10 days after injury a huge number of reactive astrocytes with pronounced hypertrophy of cell body and processes ((g) inset) form glial scar around the lesion site. ((h) and (i)) Ten successive HBOT significantly reduced glial scar formation, and the majority of astrocytes attained fibrous morphology ((i) inset). Rectangles indicate where the high magnification images are taken from. Scale bar = 50 μm.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4417949&req=5

fig1: Effect of repetitive HBOT on GFAP expression after CSI. CSI provoked upregulation of GFAP expression both at mRNA (a) and protein (b) levels in the injured cortex compared to intact control and sham-operated animals, while repetitive HBOT reduced levels of GFAP mRNA to those detected in control groups. (a) Bars represent mean ± SEM of GFAP mRNA (relative to GAPDH). (b) Immunoblot analysis showed that GFAP was present as a single band with a molecular mass of about 50 kDa. Bars represent mean ± SEM of GFAP protein content (relative to β-actin). Samples are from 4 animals per each group. Dot line represents mean of GFAP mRNA or protein level ± SEM (gray area) measured in control animals. Letters indicate significance levels (P < 0.005) between lesioned (L) and intact control group, 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 t-test. (c) The luminosity of glial scar is obtained by measuring GFAP staining intensity around the lesion site and presented on histogram. ((d) and (e)) Throughout the cortex of intact rats a small number of fibrous GFAP+ astrocytes is seen. ((f) and (g)) At 10 days after injury a huge number of reactive astrocytes with pronounced hypertrophy of cell body and processes ((g) inset) form glial scar around the lesion site. ((h) and (i)) Ten successive HBOT significantly reduced glial scar formation, and the majority of astrocytes attained fibrous morphology ((i) inset). Rectangles indicate where the high magnification images are taken from. Scale bar = 50 μm.
Mentions: Real-time PCR analysis was used to evaluate the effect of HBOT and CSI on GFAP gene expression. After CSI, the mRNA level of GFAP was increased 4-fold (P < 0.005) in the injured cortex with respect to intact control and sham-operated animals. In contrast, repetitive HBOT induced downregulation of GFAP mRNA expression to levels detected in control groups (Figure 1(a)).

Bottom Line: The exact mechanisms by which treatment with hyperbaric oxygen (HBOT) exerts its beneficial effects on recovery after brain injury are still unrevealed.Data obtained using real-time polymerase chain reaction, Western blot, and immunohistochemical and immunofluorescence analyses revealed that repetitive HBOT applied after the CSI attenuates reactive astrogliosis and glial scarring, and reduces expression of GFAP (glial fibrillary acidic protein), vimentin, and ICAM-1 (intercellular adhesion molecule-1) both at gene and tissue levels.Accordingly, repetitive HBOT, by prevention of glial scarring and limiting of expression of inflammatory mediators, supports formation of more permissive environment for repair and regeneration.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurobiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, 11060 Belgrade, Serbia.

ABSTRACT
The exact mechanisms by which treatment with hyperbaric oxygen (HBOT) exerts its beneficial effects on recovery after brain injury are still unrevealed. Therefore, in this study we investigated the influence of repetitive HBOT on the reactive astrogliosis and expression of mediators of inflammation after cortical stab injury (CSI). CSI was performed on male Wistar rats, divided into control, sham, and lesioned groups with appropriate HBO. The HBOT protocol was as follows: 10 minutes of slow compression, 2.5 atmospheres absolute (ATA) for 60 minutes, and 10 minutes of slow decompression, once a day for 10 consecutive days. Data obtained using real-time polymerase chain reaction, Western blot, and immunohistochemical and immunofluorescence analyses revealed that repetitive HBOT applied after the CSI attenuates reactive astrogliosis and glial scarring, and reduces expression of GFAP (glial fibrillary acidic protein), vimentin, and ICAM-1 (intercellular adhesion molecule-1) both at gene and tissue levels. In addition, HBOT prevents expression of CD40 and its ligand CD40L on microglia, neutrophils, cortical neurons, and reactive astrocytes. Accordingly, repetitive HBOT, by prevention of glial scarring and limiting of expression of inflammatory mediators, supports formation of more permissive environment for repair and regeneration.

No MeSH data available.


Related in: MedlinePlus