Effect of Hyperbaric Oxygen on Proliferation and Gene Expression of Human Chondrocytes: An In Vitro Study

The effect of hyperbaric oxygen therapy on oxidative stress and inflammation in patients with diabetic foot ulcers: A preliminary study

Introduction

Patients with an uncontrolled glycemic index develop a wide variety of pathologies associated with diabetes, such as diabetic foot ulcers (DFUs). Hyperbaric oxygen therapy (HBOT) is an adjunctive therapy used to heal wounds and prevent lower extremity amputations in this population.

Objective

This preliminary study aimed to evaluate how HBOT impacts inflammation in patients with Wagner stages 2-4 DFUs by analyzing its effect on the gene expression of key oxidative stress regulators SOD1, SOD2, and GPX2, of pro-inflammatory cytokines TNFα, IL-1β, IL-4, and IL-12, and of the NLRP3 inflammasome.

Methods

The effect of HBOT was assessed in 15 patients with Wagner stages 2-4 DFUs that underwent 30 sessions in the hyperbaric chamber. This protocol is registered on Clinical Trials under the title Hyperbaric Oxygen Therapy in Diabetic Foot (July 15, 2024) with the number NCT06502808. Blood samples were collected, and relative gene expression was assessed by quantitative real-time polymerase chain reaction (qPCR).

Results

The hyperbaric chamber treatment increased the expression of SOD1 and GPX2 genes (0.4 and 3 times, respectively) after 30 sessions compared to baseline levels. Similarly, the gene expression of pro-inflammatory cytokines IL-1β, IL-12, IL-4, and NLRP3 increased after 30 sessions (2.1, 0.4, 1.5, and 1.2, respectively), while the expression of the TNFα gene decreased (0.5 times). Clinically, the patients' lesions were fully resolved.

Conclusions

HBOT directly influences the gene expression of several potent antioxidants and pro-inflammatory cytokines, thus favoring angiogenesis and blood circulation in the extremities.

Revisiting the role of hyperbaric oxygen therapy in knee injuries: Potential benefits and mechanisms

Knee injury negatively impacts routine activities and quality of life of millions of people every year. Disruption of tendons, ligaments, and articular cartilage are major causes of knee lesions, leading to social and economic losses. Besides the attempts for an optimal recovery of knee function after surgery, the joint healing process is not always adequate given the nature of intra-articular environment. Based on that, different therapeutic methods attempt to improve healing capacity. Hyperbaric oxygen therapy (HBOT) is an innovative biophysical approach that can be used as an adjuvant treatment post-knee surgery, to potentially prevent chronic disorders that commonly follows knee injuries. Given the well-recognized role of HBOT in improving wound healing, further research is necessary to clarify the benefits of HBOT in damaged musculoskeletal tissues, especially knee disorders. Here, we review important mechanisms of action for HBOT-induced healing including the induction of angiogenesis, modulation of inflammation and extracellular matrix components, and activation of parenchyma cells-key events to restore knee function after injury. This review discusses the basic science of the healing process in knee injuries, the role of oxygen during cicatrization, and shed light on the promising actions of HBOT in treating knee disorders, such as tendon, ligament, and cartilage injuries.

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.