Effect of hyperoxia at 1 and 2 ATA on hypoxia and hypercapnia in human skin during experimental inflammation

Abbot, NC; Beck, J. S.; Carnochan, F. M. T.; Gibbs, J H; Harrison, David K.; James, P. B.; Lowe, John

doi:10.1152/jappl.1994.77.2.767

Cited by 17 publications

(6 citation statements)

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“…To date, the exact regulatory mechanisms that govern local tissue oxygenation in L.-infected tissues are unknown. In L. major-infected tissues of resistant C57BL/6 mice, transient infection-induced metabolic oxygen demands (Campbell et al, 2014) and/or transient impairment of local tissue perfusion (Abbot et al, 1994;Melican et al, 2008;Massberg et al, 2010) might contribute to the low oxygen values. It is tempting to speculate that in mice displaying a non-healing phenotype (such as BALB/c mice) the NOdependent anti-leishmanial activity of lesional macrophages may be continuously extinguished, because pO 2 on the site of infection might not return to normal levels (as in C57BL/6 healer mice).…”

Section: Discussionmentioning

confidence: 99%

Hypoxia in Leishmania major Skin Lesions Impairs the NO-Dependent Leishmanicidal Activity of Macrophages

Mahnke

Meier

Schatz

et al. 2014

Journal of Investigative Dermatology

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Cure of infections with Leishmania major is critically dependent on the ability of macrophages to induce the type 2 nitic oxide (NO) synthase (NOS2) that produces high levels of NO in the presence of ample oxygen. Therefore, we analyzed the oxygen levels found in leishmanial skin lesions and their effect on the NOS2-dependent leishmanicidal activity of macrophages (MΦ). When L. major skin lesions of self-healing C57BL/6 mice reached their maximum size, the infected tissue displayed low oxygen levels (pO2∼21 Torr). MΦ activated under these oxygen tensions failed to produce sufficient amounts of NO to clear L. major. Nos2-deficient and hypoxic wild-type macrophages displayed a similar phenotype. Killing was restored when MΦ were reoxygenated or exposed to a NO donor. The resolution of the lesion in C57BL/6 mice was paralleled by an increase of lesional pO2. When mice were kept under normobaric hypoxia, this caused a persistent suppression of the lesional pO2 and a concurrent increase of the parasite load. In Nos2-deficient mice, there was no effect of atmospheric hypoxia. Low oxygen levels found at leishmanial skin lesions impaired the NOS2-dependent leishmanicidal activity of MΦ. Hence, tissue oxygenation represents an underestimated local milieu factor that participates in the persistence of Leishmania.

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Section: Discussionmentioning

confidence: 99%

Hypoxia in Leishmania major Skin Lesions Impairs the NO-Dependent Leishmanicidal Activity of Macrophages

Mahnke

Meier

Schatz

et al. 2014

Journal of Investigative Dermatology

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“…HBOT has been shown to possess potent anti-inflammatory properties in both animal [55,67,68] and human studies [10,11,20,46,69] and has been reported to decrease the production of pro-inflammatory cytokines (such as TNF-alpha, interferon-gamma, IL-1 and IL-6) in both animal [66,70] and human studies [20,49] as well as increase IL-10 levels [71]. Several of the reviewed studies (including human studies and animal models) reported a decrease in inflammation as measured by reduced tissue edema and histopathological changes, as well as a decrease in TNF-alpha, IL-1 and IL-6 with HBOT [49,54,61,63,66].…”

Section: Discussionmentioning

confidence: 99%

Hyperbaric oxygen treatment for inflammatory bowel disease: a systematic review and analysis

Rossignol¹

2012

Med Gas Res

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BackgroundTraditionally, hyperbaric oxygen treatment (HBOT) has been used to treat a limited repertoire of disease, including decompression sickness and healing of problem wounds. However, some investigators have used HBOT to treat inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis.MethodsComprehensive searches were conducted in 8 scientific databases through 2011 to identify publications using HBOT in IBD. Human studies and animal models were collated separately.ResultsThirteen studies of HBOT in Crohn's disease and 6 studies in ulcerative colitis were identified. In all studies, participants had severe disease refractory to standard medical treatments, including corticosteroids, immunomodulators and anti-inflammatory medications. In patients with Crohn's disease, 31/40 (78%) had clinical improvements with HBOT, while all 39 patients with ulcerative colitis improved. One study in Crohn's disease reported a significant decrease in proinflammatory cytokines (IL-1, IL-6 and TNF-alpha) and one study in ulcerative colitis reported a decrease in IL-6 with HBOT. Adverse events were minimal. Twelve publications reported using HBOT in animal models of experimentally-induced IBD, including several studies reporting decreased markers of inflammation or immune dysregulation, including TNF-alpha (3 studies), IL-1beta (2 studies), neopterin (1 study) and myeloperoxidase activity (5 studies). HBOT also decreased oxidative stress markers including malondialdehyde (3 studies) and plasma carbonyl content (2 studies), except for one study that reported increased plasma carbonyl content. Several studies reported HBOT lowered nitric oxide (3 studies) and nitric oxide synthase (3 studies) and one study reported a decrease in prostaglandin E2 levels. Four animal studies reported decreased edema or colonic tissue weight with HBOT, and 8 studies reported microscopic improvements on histopathological examination. Although most publications reported improvements with HBOT, some studies suffered from limitations, including possible publication and referral biases, the lack of a control group, the retrospective nature and a small number of participants.ConclusionsHBOT lowered markers of inflammation and oxidative stress and ameliorated IBD in both human and animal studies. Most treated patients were refractory to standard medical treatments. Additional studies are warranted to investigate the effects of HBOT on biomarkers of oxidative stress and inflammation as well as clinical outcomes in individuals with IBD.

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“…by accumulation of inflammatory cells, more than the local blood flow, which leads to lactic acid accumulation (Harrison et al . 1986; Abbot et al . 1994).…”

Section: Introductionmentioning

confidence: 99%

The pH response of rat cutaneous nociceptors correlates with extracellular [Na⁺] and is increased under amiloride

Steen

Wegner

Reeh

1999

Eur J of Neuroscience

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Excess hydrogen ions induce sustained nociceptor excitation as well as pain, and this has been suggested, with evidence from sensory ganglion cells, to result from gating a slowly inactivating sodium/calcium inward current. In the rat skin-nerve preparation, isolated receptive fields of pH-sensitive C-fibre terminals were exposed to low-pH solutions of various sodium concentrations. The pH responses showed a good correlation with log [Na+]e, which supports the above model. Amiloride has previously been shown to block a pH-induced Na+ current involved in sensory transduction in hamster taste cells; however, it has been shown to act differently in cutaneous nociceptors. Amiloride induced a dose-dependent increase in and prolongation of the nociceptive pH responses, with a prominent acceleration of the onset. The latter could be mimicked by replacing external sodium with sucrose, thus impeding sodium-proton antiport. Together, the findings indicate functional expression of amiloride-sensitive Na+/H+-antiporters, which enable the nociceptive nerve endings to extrude invading H+. Intracellular acidification may thus compete with Na+/H+ exchange, and pHi may be decisive in the transduction of nociception and pain from tissue acidosis.

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Effect of hyperoxia at 1 and 2 ATA on hypoxia and hypercapnia in human skin during experimental inflammation

Cited by 17 publications

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Hypoxia in Leishmania major Skin Lesions Impairs the NO-Dependent Leishmanicidal Activity of Macrophages

Hypoxia in Leishmania major Skin Lesions Impairs the NO-Dependent Leishmanicidal Activity of Macrophages

Hyperbaric oxygen treatment for inflammatory bowel disease: a systematic review and analysis

The pH response of rat cutaneous nociceptors correlates with extracellular [Na⁺] and is increased under amiloride

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Effect of hyperoxia at 1 and 2 ATA on hypoxia and hypercapnia in human skin during experimental inflammation

Cited by 17 publications

References 0 publications

Hypoxia in Leishmania major Skin Lesions Impairs the NO-Dependent Leishmanicidal Activity of Macrophages

Hypoxia in Leishmania major Skin Lesions Impairs the NO-Dependent Leishmanicidal Activity of Macrophages

Hyperbaric oxygen treatment for inflammatory bowel disease: a systematic review and analysis

The pH response of rat cutaneous nociceptors correlates with extracellular [Na+] and is increased under amiloride

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The pH response of rat cutaneous nociceptors correlates with extracellular [Na⁺] and is increased under amiloride