Hyperbaric oxygen therapy is not associated with oxidative stress assessed using plasma F2-isoprostanes and isofurans

Hyperbaric Oxygen Therapy Attenuated the Motor Coordination and Cognitive Impairment of Polyglutamine Spinocerebellar Ataxia SCA17 Mice

Spinocerebellar ataxias (SCAs) are a large and diverse group of autosomal-dominant neurodegenerative diseases. No drugs have been approved for these relentlessly progressive and fatal SCAs. Our previous studies indicate that oxidative stress, neuroinflammation, and neuronal apoptosis are elevated in the SCA17 mice, which are the main therapeutic targets of hyperbaric oxygen treatment (HBOT). HBOT is considered to be an alternative and less invasive therapy for SCAs. In this study, we evaluated the HBOT (2.2 ATA for 14 days) effect and the persistence for the management of SCA17 mice and their wild-type littermates. We found HBOT attenuated the motor coordination and cognitive impairment of SCA17 mice and which persisted for about 1 month after the treatment. The results of several biochemistry and liver/kidney hematoxylin and eosin staining show the HBOT condition has no obvious toxicity in the mice. Immunostaining analyses show that the neuroprotective effect of HBOT could be through the promotion of BDNF production and the amelioration of neuroinflammation. Surprisingly, HBOT executes different effects on the male and female SCA17 mice, including the reduction of neuroinflammation and activation of CaMKII and ERK. This study suggests HBOT is a potential alternative therapeutic treatment for SCA17. Accumulated findings have revealed the similarity in disease pathomechanisms and possible therapeutic strategies in polyQ diseases; therefore, HBOT could be an optional treatment as well as the other polyQ diseases.

Hyperbaric oxygen therapy as an adjunct treatment of periodontitis, MRONJ, and ONJ: a systematic literature review

OBJECTIVE

To review the available prospective literature on hyperbaric oxygen (HBO) therapy for periodontal conditions.

MATERIALS AND METHODS

A comprehensive electronic and manual search was performed to identify clinical studies on adult patients who underwent hyperbaric oxygen therapy for periodontal treatments. A systematic literature search was conducted in PubMed, Cochrane, and Dentistry Oral Sciences Source databases.

RESULTS

Fourteen articles were included in the final literature review, of which five were RCTs and 11 were prospective clinical studies. Four studies discussed HBO as an adjunct to nonsurgical treatment of periodontitis, eight reported on HBO and osteoradionecrosis, and one examined HBO in bisphosphonate-related necrosis of the jaws.

CONCLUSIONS

HBO has shown superior efficacy compared to antibiotics as a prophylactic measure in preventing osteoradionecrosis (ORN) in patients with a history of high mandibular irradiation. Clinicians should consider referring such patients for HBO therapy before and after tooth extractions. However, for the surgical excision of existing ORN lesions, HBO therapy does not yield significant benefits but does not negatively impact outcomes either. Regarding the treatment of periodontitis patients, the variability among studies prevents definitive conclusions. HBO therapy as an adjunct to SRP in periodontitis treatment produces mixed results.

CLINICAL RELEVANCE

This study's clinical relevance lies in its exploration of the potential benefits of HBO for periodontal conditions. Also, it provides clinicians with insights into when and how to integrate HBO therapy into their treatment approaches, particularly for patients with a history of irradiation and those undergoing complex dental procedures.

Adverse Events During Hyperbaric Oxygen Therapy – Literature Review

As any other therapy method, hiperbaric oxygen therapy is connected with the risk of complications. The article is a review of the results of research on adverse events of hyperbaric oxygen therapy. The most common are: borotrauma of the middle ear, paranasal sinuses or lungs, oxygen toxicity can be pulmonary, ocular in extreme cases leading to cataracts, claustrophobia, pulmonary edema or hypoglycaemia. Research has shown that these events occur in the presence of high oxygen concentration or high pressure. Depending on the severity of complications, they are short-term not causing discontinuation of therapy or long-term excluding continuation of treatment. However adverse events connected with oxygen therapy are not common and are usually mild. This confirms that HBOT is an effective and safe method of treating decompression sickness, carbon monoxide poisoning, and the treatment of chronic wounds, delayed radiation injuries or necrotic soft tissue infections.

The Effects of Hyperbaric Oxygenation on Oxidative Stress, Inflammation and Angiogenesis

Hyperbaric oxygen therapy (HBOT) is commonly used as treatment in several diseases, such as non-healing chronic wounds, late radiation injuries and carbon monoxide poisoning. Ongoing research into HBOT has shown that preconditioning for surgery is a potential new treatment application, which may reduce complication rates and hospital stay. In this review, the effect of HBOT on oxidative stress, inflammation and angiogenesis is investigated to better understand the potential mechanisms underlying preconditioning for surgery using HBOT. A systematic search was conducted to retrieve studies measuring markers of oxidative stress, inflammation, or angiogenesis in humans. Analysis of the included studies showed that HBOT-induced oxidative stress reduces the concentrations of pro-inflammatory acute phase proteins, interleukins and cytokines and increases growth factors and other pro-angiogenesis cytokines. Several articles only noted this surge after the first HBOT session or for a short duration after each session. The anti-inflammatory status following HBOT may be mediated by hyperoxia interfering with NF-κB and IκBα. Further research into the effect of HBOT on inflammation and angiogenesis is needed to determine the implications of these findings for clinical practice.

Hyperbaric hyperoxemia as a risk factor for ventilator-acquired pneumonia?

OBJECTIVES

Ventilator-acquired pneumonia (VAP) is the leading cause of serious associated infections in Intensive Care Units (ICU) and is associated with significant morbidity. The use of hyperbaric oxygen therapy (HBOT) in patients on mechanical ventilation may increase exposure to certain risk factors such as hyperoxemia and the need for multiple transfers. The aim of our study was to assess the relationship between HBOT and VAP.

METHOD

This retrospective observational study was performed from March 2017 to March 2018 in a 10-bed ICU using HBOT. All patients receiving mechanical ventilation (MV) for more than 48 hours were eligible. VAP was defined using clinical and radiological criteria. Data collection was carried out via digital medical records. Risk factors for VAP were determined by univariate and multivariate analysis.

RESULTS

Forty-two (23%) of the 182 patients enrolled developed at least one episode of VAP. One hundred and twenty-four (68%) patients received HBOT. The incidence rate of VAP was 34 per 1000 ventilator days. The occurrence of VAP was significantly associated with immunosuppression (p<0.029), MV duration (5 [3-7] vs 8 [5-11.5] days, p<0.0001), length of stay (8 [5-13] vs 19.5 [13-32] days, p<0.0001), reintubation (p<0.0001), intra-hospital transport (p = 0.001), use of paralytic agents (p = 0.013), tracheotomy (p = 0.003) and prone position (p = 0.003). The use of HBOT was not associated with the occurrence of VAP. Multivariate analysis identified reintubation (OR: 8.3 [2.6-26.6]; p<0.0001), intra-hospital transport (OR: 3.5 [1.3-9.2]; p = 0.011) and the use of paralytic agents (OR: 3.3 [1.3-8.4]; p = 0.014) as independent risk factors for VAP.

CONCLUSION

Known risk factors for VAP are to be found within our ICU population. HBOT, however, is not an extra risk factor for VAP within this group. Further experimental and clinical investigations are needed to understand the impact of HBOT on the occurrence of VAP and on physiological microbiome.

Increased inspired oxygen concentration does not adversely affect oxidative stress and the resolution of inflammation during reperfusion in patients undergoing knee replacement surgery

The level of inspired oxygen during surgery may modify free radical release, and reperfusion injury. This controlled trial examined the effect of inspired oxygen on F₂-isoprostanes (F₂-IsoPs), isofurans (IsoFs), and specialized mediators of inflammation resolution (SPM) during knee replacement surgery. Patients received either 30% O₂ (control n = 21), 50% O₂ (n = 20), or 80% O₂ (n = 19) O₂, in a parallel design. Hemoglobin (Hb) was measured throughout the surgery and F₂-IsoPs, IsoFs and SPM were analyzed by mass spectrometry. The effect of O₂ on F₂-IsoPs and IsoFs was examined during tourniquet inflation and after tourniquet release. SPM were measured at baseline and the end of surgery. There was a significant interaction between O₂ and Hb concentrations with plasma IsoFs during tourniquet inflation. An increase in plasma IsoFs over time was attenuated in the 80% O₂ group (p=.012) compared with the 30% O₂ group after adjusting for Hb concentration. After tourniquet release, plasma F₂-IsoPs were significantly lower in the 50% and 80% O₂ groups (p=.009 and p=.001, respectively) compared with the 30% O₂ group after adjustment for Hb concentration. The SPM RvD2 and RvE2 were increased with 50% and 80% O₂ (RvD2, p=.014 and p=.002, respectively; RvE2, p=.032 with 50% O₂) compared with the 30% O₂ group, in analyses that corrected for Hb concentration. We have shown for the first time that higher O₂ levels may be beneficial in reducing oxidative stress and increasing resolution of inflammation during surgery that involves reperfusion after application of a tourniquet.

Hyperbaric oxygen and radiation therapy: a review

About 5% of cancer patients treated with radiotherapy will have severe late-onset toxicity. Hyperbaric oxygen therapy (HBOT) has been used as a treatment for radiation injuries for decades, with many publications presenting data from small series or individual cases. Moreover, we know that the hypoxic areas of tumours are more resistant to radiation. HBOT increases the oxygen tension in tissues and, theoretically, it should enhance the efficiency of radiotherapy. To better understand how HBOT works, we carried out this bibliographic review. We found Grade B and C evidence that at pressures exceeding 2 absolute atmospheres (ata), HBOT reduced late-onset radiation injuries to the head and neck, bone, prostate and bladder. It also appeared to prevent osteoradionecrosis after exodontia in irradiated areas. Finally, HBOT at 2 ata increased the effectiveness of radiation in head and neck tumours and achieved promising results in the local control of high-grade gliomas.

Evaluation of Oxidative Stress in Patients with Difficult-to-Heal Skin Wounds Treated with Hyperbaric Oxygen

Objective

To determine the concentration of thiobarbituric acid reactive substances (TBARS) in erythrocytes and blood plasma, and the activities of selected antioxidant enzymes: catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in erythrocytes in patients receiving hyperbaric oxygen (HBO) treatment due to difficult-to-heal “skin wounds”. Material and Methods. Indices of oxidative stress were assessed in venous blood taken from 23 patients three times: immediately before HBO procedure, approx. 5 minutes after leaving the hyperbaric chamber, and after 25 HBO procedures. Moreover, selected blood counts were measured in the collected material two times: prior to treatment and after 25 HBO procedures.

Results

A statistically significant positive correlation between the CAT activity and the TBARS concentration in the erythrocytes of patients was found before treatment in the hyperbaric chamber (r = 0.394; P ≤ 0.05). No statistically significant changes in the TBARS concentration in erythrocytes and blood plasma were observed both after the first HBO procedure and after 25 procedures. No statistically significant changes in the activities of CAT, SOD, and GPx were noted. Platelet count decreased by 18.7% (P ≤ 0.05) after 25 HBO procedures. Granulocyte count decreased by approx. 21% (P ≤ 0.05), and granulocyte percentage by 11.8% (P ≤ 0.01). In turn, the percentage of lymphocytes and monocytes increased after the treatment by 16.6% (P < 0.05) and 16.4% (P < 0.05), respectively.

Conclusions

Exposure to HBO due to difficult-to-heal skin wounds does not significantly affect the levels of oxidative stress in the peripheral blood of patients and, from the point of view of oxidation–reduction processes, appears to be a safe therapeutic method for the treatment of chronic wounds.

Environmental risk factors and their footprints in vivo - A proposal for the classification of oxidative stress biomarkers

Environmental agents, including socioeconomic condition, and host factors can act as causal agents and risk factors in disease. We use biomarkers and sociomarkers to study causal factors, such as overproduction of reactive oxygen species (ROS) which could play a role in disease through oxidative stress. It is therefore important to define the exact meaning of the biomarker we measure. In this review we attempt a classification of biomarkers related to oxidative stress based on their biological meaning. We define as type zero biomarkers the direct measurement of ROS in vivo in patients. Type 1 biomarkers are the most frequently used indicators of oxidative stress, represented by oxidized lipids, proteins or nucleic acids and their bases. Type 2 biomarkers are indicators of the activation of biochemical pathways that can lead to the formation of ROS. Type 3 biomarkers are host factors such as small-molecular weight antioxidants and antioxidant enzymes, while type 4 biomarkers measure genetic factors and mutations that could modify the susceptibility of an individual to oxidative stress. We also discuss whether biomarkers are actionable or not, that is if the specific blockade of these molecules can ameliorate disease or if they are just surrogate markers.

The proposed classification of biomarkers of oxidative stress based on their meaning and ambiguities, within the theoretical framework of the oxidative stress theory of disease may help identify those diseases, and individuals, where oxidative stress has a causal role, to allow targeted therapy and personalized medicine.

L-Carnitine Is Involved in Hyperbaric Oxygen-Mediated Therapeutic Effects in High Fat Diet-Induced Lipid Metabolism Dysfunction

Lipid metabolism dysfunction and obesity are serious health issues to human beings. The current study investigated the effects of hyperbaric oxygen (HBO) against high fat diet (HFD)-induced lipid metabolism dysfunction and the roles of L-carnitine. C57/B6 mice were fed with HFD or normal chew diet, with or without HBO treatment. Histopathological methods were used to assess the adipose tissues, serum free fatty acid (FFA) levels were assessed with enzymatic methods, and the endogenous circulation and skeletal muscle L-carnitine levels were assessed with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Additionally, western blotting was used to assess the expression levels of PPARα, CPT1b, pHSL/HSL, and UCP1. HFD treatment increased body/adipose tissue weight, serum FFA levels, circulation L-carnitines and decreased skeletal muscle L-carnitine levels, while HBO treatment alleviated such changes. Moreover, HFD treatment increased fatty acid deposition in adipose tissues and decreased the expression of HSL, while HBO treatment alleviated such changes. Additionally, HFD treatment decreased the expression levels of PPARα and increased those of CPT1b in skeletal muscle, while HBO treatment effectively reverted such changes as well. In brown adipose tissues, HFD increased the expression of UCP1 and the phosphorylation of HSL, which was abolished by HBO treatment as well. In summary, HBO treatment may alleviate HFD-induced fatty acid metabolism dysfunction in C57/B6 mice, which seems to be associated with circulation and skeletal muscle L-carnitine levels and PPARα expression.