Limits...
Endothelial Antioxidant-1: a Key Mediator of Copper-dependent Wound Healing in vivo

View Article: PubMed Central - PubMed

ABSTRACT

Copper (Cu), an essential nutrient, promotes wound healing, however, target of Cu action and underlying mechanisms remain elusive. Cu chaperone Antioxidant-1 (Atox1) in the cytosol supplies Cu to the secretory enzymes such as lysyl oxidase (LOX), while Atox1 in the nucleus functions as a Cu-dependent transcription factor. Using mouse cutaneous wound healing model, here we show that Cu content (by X-ray Fluorescence Microscopy) and nuclear Atox1 are increased after wounding, and that wound healing with and without Cu treatment is impaired in Atox1−/− mice. Endothelial cell (EC)-specific Atox1−/− mice and gene transfer of nuclear-target Atox1 in Atox1−/− mice reveal that Atox1 in ECs as well as transcription factor function of Atox1 are required for wound healing. Mechanistically, Atox1−/− mice show reduced Atox1 target proteins such as p47phox NADPH oxidase and cyclin D1 as well as extracellular matrix Cu enzyme LOX activity in wound tissues. This in turn results in reducing O2− production in ECs, NFkB activity, cell proliferation and collagen formation, thereby inhibiting angiogenesis, macrophage recruitment and extracellular matrix maturation. Our findings suggest that Cu-dependent transcription factor/Cu chaperone Atox1 in ECs plays an important role to sense Cu to accelerate wound angiogenesis and healing.

No MeSH data available.


Related in: MedlinePlus

Abundance and spatial distribution of Cu in cutaneous wounds from Atox1βˆ’/βˆ’ and WT mice.Cu content in wound tissues at day 0 and 7 after injury in Atox1βˆ’/βˆ’ and WT mice was measured by inductively coupled plasma mass spectrometry (ICP-MS) (A) or synchrotron-based x-ray fluorescence (SXRF) (B). In (B), SXRF scans (1–2 seconds per pixel) were performed in paraffin-embedded tissue (upper panel). The maximum and minimum threshold values in ΞΌg/cm2 are shown below each frame. Map of Cu shows areas of the lowest to the highest content scaled to a rainbow color (bottom). Total sulfur is used as a surrogate for total cellular protein and to visualize the morphology of tissue sections2728. A graph represents mean ± SE of Cu content in the wounds (A) or medial Cu/S ratio (B). * < 0.05 vs. day 0 or WT.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC5036036&req=5

f3: Abundance and spatial distribution of Cu in cutaneous wounds from Atox1βˆ’/βˆ’ and WT mice.Cu content in wound tissues at day 0 and 7 after injury in Atox1βˆ’/βˆ’ and WT mice was measured by inductively coupled plasma mass spectrometry (ICP-MS) (A) or synchrotron-based x-ray fluorescence (SXRF) (B). In (B), SXRF scans (1–2 seconds per pixel) were performed in paraffin-embedded tissue (upper panel). The maximum and minimum threshold values in ΞΌg/cm2 are shown below each frame. Map of Cu shows areas of the lowest to the highest content scaled to a rainbow color (bottom). Total sulfur is used as a surrogate for total cellular protein and to visualize the morphology of tissue sections2728. A graph represents mean ± SE of Cu content in the wounds (A) or medial Cu/S ratio (B). * < 0.05 vs. day 0 or WT.

Mentions: To determine if endogenous Cu level is altered after wound injury, we measured the Cu content in wound tissues of WT and Atox1βˆ’/βˆ’ mice using ICP-MS (Fig. 3A) and SXFM (Fig. 3B). We found that Cu content was markedly increased in all the layers of wounded tissue with more in epidermis area at day 7 in WT mice. Of note, Cu levels were normalized by sulfur levels, which was used as a surrogate for total cellular protein and to visualize the morphology of tissue sections2828. As shown in Fig. 3B, Atox1βˆ’/βˆ’ mice exhibit increased Cu levels in the non-wounded and wounded tissue as compared to WT mice. These results suggest that delayed wound healing in Atox1βˆ’/βˆ’ mice is not due to decreased Cu level in wounds but to the loss of Cu sensor function of Atox1.


Endothelial Antioxidant-1: a Key Mediator of Copper-dependent Wound Healing in vivo
Abundance and spatial distribution of Cu in cutaneous wounds from Atox1βˆ’/βˆ’ and WT mice.Cu content in wound tissues at day 0 and 7 after injury in Atox1βˆ’/βˆ’ and WT mice was measured by inductively coupled plasma mass spectrometry (ICP-MS) (A) or synchrotron-based x-ray fluorescence (SXRF) (B). In (B), SXRF scans (1–2 seconds per pixel) were performed in paraffin-embedded tissue (upper panel). The maximum and minimum threshold values in ΞΌg/cm2 are shown below each frame. Map of Cu shows areas of the lowest to the highest content scaled to a rainbow color (bottom). Total sulfur is used as a surrogate for total cellular protein and to visualize the morphology of tissue sections2728. A graph represents mean ± SE of Cu content in the wounds (A) or medial Cu/S ratio (B). * < 0.05 vs. day 0 or WT.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5036036&req=5

f3: Abundance and spatial distribution of Cu in cutaneous wounds from Atox1βˆ’/βˆ’ and WT mice.Cu content in wound tissues at day 0 and 7 after injury in Atox1βˆ’/βˆ’ and WT mice was measured by inductively coupled plasma mass spectrometry (ICP-MS) (A) or synchrotron-based x-ray fluorescence (SXRF) (B). In (B), SXRF scans (1–2 seconds per pixel) were performed in paraffin-embedded tissue (upper panel). The maximum and minimum threshold values in ΞΌg/cm2 are shown below each frame. Map of Cu shows areas of the lowest to the highest content scaled to a rainbow color (bottom). Total sulfur is used as a surrogate for total cellular protein and to visualize the morphology of tissue sections2728. A graph represents mean ± SE of Cu content in the wounds (A) or medial Cu/S ratio (B). * < 0.05 vs. day 0 or WT.
Mentions: To determine if endogenous Cu level is altered after wound injury, we measured the Cu content in wound tissues of WT and Atox1βˆ’/βˆ’ mice using ICP-MS (Fig. 3A) and SXFM (Fig. 3B). We found that Cu content was markedly increased in all the layers of wounded tissue with more in epidermis area at day 7 in WT mice. Of note, Cu levels were normalized by sulfur levels, which was used as a surrogate for total cellular protein and to visualize the morphology of tissue sections2828. As shown in Fig. 3B, Atox1βˆ’/βˆ’ mice exhibit increased Cu levels in the non-wounded and wounded tissue as compared to WT mice. These results suggest that delayed wound healing in Atox1βˆ’/βˆ’ mice is not due to decreased Cu level in wounds but to the loss of Cu sensor function of Atox1.

View Article: PubMed Central - PubMed

ABSTRACT

Copper (Cu), an essential nutrient, promotes wound healing, however, target of Cu action and underlying mechanisms remain elusive. Cu chaperone Antioxidant-1 (Atox1) in the cytosol supplies Cu to the secretory enzymes such as lysyl oxidase (LOX), while Atox1 in the nucleus functions as a Cu-dependent transcription factor. Using mouse cutaneous wound healing model, here we show that Cu content (by X-ray Fluorescence Microscopy) and nuclear Atox1 are increased after wounding, and that wound healing with and without Cu treatment is impaired in Atox1&minus;/&minus; mice. Endothelial cell (EC)-specific Atox1&minus;/&minus; mice and gene transfer of nuclear-target Atox1 in Atox1&minus;/&minus; mice reveal that Atox1 in ECs as well as transcription factor function of Atox1 are required for wound healing. Mechanistically, Atox1&minus;/&minus; mice show reduced Atox1 target proteins such as p47phox NADPH oxidase and cyclin D1 as well as extracellular matrix Cu enzyme LOX activity in wound tissues. This in turn results in reducing O2&minus; production in ECs, NFkB activity, cell proliferation and collagen formation, thereby inhibiting angiogenesis, macrophage recruitment and extracellular matrix maturation. Our findings suggest that Cu-dependent transcription factor/Cu chaperone Atox1 in ECs plays an important role to sense Cu to accelerate wound angiogenesis and healing.

No MeSH data available.


Related in: MedlinePlus