Controlled ozone therapy modulates the neurodegenerative changes in the albino rat

Background

Ageing is associated with progressive changes in the brain, including increased oxidative stress, chronic low-grade inflammation and a build-up of activated glial cells - a process called gliosis - that can contribute to cognitive decline. Researchers investigating complementary interventions for age-related neurodegeneration have looked at ozone therapy, which delivers controlled, low concentrations of ozone gas, for its potential antioxidant and anti-inflammatory effects on ageing brain tissue. This study, published in Annals of Anatomy - Anatomischer Anzeiger, examined whether controlled ozone therapy could modulate neurodegenerative changes in the frontal cortex of aged rats.

Study design

Researchers used 40 male albino rats, divided into four groups of ten: adult control rats (three months old), adult rats treated with ozone, aged control rats (20 months old), and aged rats treated with ozone. Ozone was administered by intraperitoneal injection at a dose of 0.7 mg per kilogram of body weight, three times a week for eight weeks. The frontal cortex was then analysed using tissue biochemical assays (malondialdehyde, glutathione, superoxide dismutase and catalase levels), light microscopy with haematoxylin and eosin staining, and quantitative immunohistochemistry for markers including inducible nitric oxide synthase (iNOS), caspase-3 (a marker of programmed cell death), glial fibrillary acidic protein (GFAP, a marker of gliosis), Ki67 (a marker of cell proliferation) and acetylcholinesterase (AChE, linked to cholinergic nerve signalling). Image analysis software was used to quantify staining.

Findings

Compared with aged control rats, aged rats treated with ozone showed reduced markers of oxidative stress (lower malondialdehyde, higher glutathione, superoxide dismutase and catalase) and fewer degenerated or apoptotic cells in the frontal cortex, indicated by reduced caspase-3 staining. GFAP expression, reflecting gliosis, was downregulated in ozone-treated aged rats, and markers linked to neurogenesis (Ki67) and cholinergic signalling (AChE) improved relative to untreated aged rats. Similar, though less pronounced, changes were seen in ozone-treated adult rats compared with adult controls.

What the authors concluded

The authors concluded that controlled ozone therapy exerted protective effects on the ageing frontal cortex by reducing oxidative stress, apoptosis and gliosis, while supporting neurogenesis and cholinergic plasticity. They suggested this points to a potential therapeutic role for ozone therapy in age-related neurodegeneration, framing the findings as a basis for further investigation rather than a clinical recommendation.

Limitations of this study

This was a preclinical animal (rat) study, not a clinical trial in humans, so its findings cannot be directly extrapolated to human ageing or neurodegenerative disease. Ozone was delivered by intraperitoneal injection, a route not typically used in human ozone therapy practice (which more commonly involves major autohaemotherapy or rectal insufflation), so dosing and delivery cannot be assumed to translate directly to people. The study also used a modest number of animals per group (ten), examined a single brain region over an eight-week period, and did not model a specific neurodegenerative disease such as Alzheimer's or Parkinson's disease - it looked at general age-related brain changes. Further preclinical and clinical research is needed before any conclusions can be drawn about ozone therapy's role in human neurodegeneration.