Tea Tree And Its Anti-Inflammatory Properties

Introduction

Brief overview of the tea tree (Melaleuca alternifolia)

The tea tree is a native plant of Australia. Indigenous Australians would use the leaves of the tea tree plant to treat any wounds and cuts. Crushed leaves would be applied on an injury and then a mud pack would be used to hold the leaves in place, which helped in fighting infection. This plant is well known for its oil known as tea tree oil, which has medicinal uses such as an antifungal, antibacterial, and antiseptic agent. Tea tree oil can be used in treating skin conditions such as acne and eczema and skin infections such as wounds, burns, and insect bites.¹

Composition of tea tree oil

Key chemical components

Tea tree oil has 3 main chemical components – terpinen-4-ol, 1,8-cineole, and terpinolene:²

Terpinen-4-ol

• Has antimicrobial properties – effective against fluconazole-resistant C. albicans and methicillin-resistant S. aureus
• Inhibits proinflammatory mediators
• Can act as a potential anticancer agent
• Strong antioxidant activity from isomers – α- and γ-terpinene

1,8-cineole

• Also known as eucalyptol
• Used in respiratory disease treatment
• Has antioxidant and anti-inflammatory properties

Terpinolene (δ-terpinene)

• Used as a flavouring agent
• High antioxidant capacity
• Potential antiproliferative properties

Significance of chemical composition in anti-inflammatory properties

Both terpinen-4-ol and terpinolene can reduce proinflammatory cytokines such as interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumour necrosis (TNF-α).³ 1,8-cineole has anti-inflammatory effects in the respiratory tract and is used in treating various acute and chronic airway conditions.⁴

Mechanisms of anti-inflammatory action

Inhibition of inflammatory pathways

Reduction of cytokines

As mentioned before, terpinen-4-ol and terpinolene are both able to reduce proinflammatory cytokines (IL-6, TNF-α, IL-1β). Inhibition of these cytokines helps to mitigate the body’s inflammatory response.³

Modulation of immune response

Regulating the activity of immune cells such as lymphocytes and macrophages helps balance the body’s reaction to any damage, thus reducing inflammation.⁵

Antioxidant effects

Neutralisation of free radicals

Terpinen-4-ol scavenges free radicals, which are highly reactive molecules that can trigger inflammation. Neutralising these radicals protects the body from oxidative stress-induced inflammation.⁶

Scientific studies and tesearch

Tea tree (oil) has been used in trials for acne and results have shown that it reduced areas of inflammation. For trials in wound healing, results showed that blood flow was significantly higher with the use of tea tree oil.⁶

An in vitro study looked at the anti-inflammatory effects of tea tree oil through inhibiting protein denaturation. Protein denaturation is a cause of inflammation. The results showed that tea tree oil has significant anti-inflammatory activity.⁷

An animal study looked at the effect of tea tree oil on gene expression involved in the innate immune system in goat rumen epithelial cells. Subacute ruminal acidosis (SARA) is a digestive disorder affecting cows.8 It is caused by an endotoxin (lipopolysaccharide – LPS) which is produced by the breakdown of bacteria. This causes a cascade of inflammatory responses and the rumen's innate immune system responds to the infection. Goats with SARA have an increased rate of free LPS in their rumen, which can lead to inflammation of the rumen epithelium. The results from this study show that tea tree oil inhibits LPS-induced inflammatory expression in these cells.⁹

Application of tea tree oil in inflammatory conditions

Topical use in skincare

Acne treatment

Acne vulgaris is a chronic inflammatory disease caused by many factors, including excess sebum production. Many over-the-counter (OTC) products such as soaps, face wash, and toners have tea tree oil in them and are sometimes used in combination with other acne treatment agents such as benzoyl peroxide.¹⁰

Tea tree oil has terpinen-4-ol, which reduces the production of certain interleukins, prostaglandin E2, and TNF. It is also very effective against MRSA (methicillin-resistant Staphylococcus aureus) and CONS (coagulase-negative Staphylococcus).¹⁰

It has been shown that using tea tree oil in the treatment of acne is effective. Tea tree oil has been shown to reduce papulopustular lesions, papules, and scar lesions.¹⁰

Inhalation and aromatherapy

Respiratory conditions

Respiratory conditions such as colds, influenza, and bronchitis can be treated with tea tree oil. A study in mice showed that after mice who had inflammation inhaled tea tree oil, the results showed tea tree oil inhalation exerts a strong anti-inflammatory influence on the immune system.¹¹

Research has shown that using tea tree oil in combination with other essential oils has antimicrobial and anti-inflammatory effects against pathogens in the respiratory tract.¹²

Safety considerations

Potential side effects and allergies

Here are a few potential side effects of using tea tree oil:¹³

• Skin irritation
• Itching
• Stinging
• Allergic skin rash (dermatitis)
• Dryness
• Scaling
• Burning
• Redness

Tea tree should not be swallowed – it is toxic when swallowed. Side effects that can occur can be serious. Some side effects include:

• Decreasing levels of consciousness
• Confusion
• Ataxia – lack of coordination or muscle control of voluntary movements

Tea tree oil has had some reported adverse drug reactions with its use, with some serious reported reactions with oral administration. These include:

• Central nervous system depression
• Pneumonitis
• Somnolence

Summary

Indigenous Australians have long used the tea tree, scientifically known as Melaleuca alternifolia, as a traditional medicinal herb. Tea tree leaves have long been used as a natural remedy for cuts and wounds. Crushed leaves are applied directly to wounds to help fight infection. However, the oil extracted from the tea tree—also referred to as tea tree oil—has drawn a lot of interest due to its therapeutic qualities, which include antimicrobial, antibacterial, and antiseptic qualities.

Terpinen-4-ol, 1,8-cineole, and terpinolene are the three primary chemical constituents of tea tree oil. Strong antibacterial qualities are exhibited by terpinen-4-ol in particular, which has been demonstrated to be effective against methicillin-resistant Staphylococcus aureus (MRSA). Terpinen-4-ol has also demonstrated promise as a possible anticancer agent and has anti-inflammatory qualities. 1,8-cineole, often known as eucalyptol, is another essential ingredient that has anti-inflammatory and antioxidant qualities. It is used in the treatment of respiratory diseases. Terpinolene has strong antioxidant capabilities and possible antiproliferative effects, even though its main application is as a flavouring agent.

Tea tree oil's anti-inflammatory qualities are largely dependent on its composition of chemicals. Interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumour necrosis factor-alpha (TNF-α) are examples of pro-inflammatory cytokines that can be reduced by terpinen-4-ol and terpinolene. Additionally, 1,8-cineole helps treat a variety of acute and chronic respiratory diseases since it has anti-inflammatory properties in the respiratory tract.

Tea tree oil has been shown to have anti-inflammatory qualities through scientific investigations and research. Animal research has shown its efficacy in reducing the expression of inflammation, while in vitro investigations have revealed its strong anti-inflammatory properties. Tea tree oil formulations have been found to efficiently reduce scar lesions and papulopustular lesions in acne patients, a disease for which few trials have reported benefits in treating inflammation.

Due to its antibacterial and anti-inflammatory qualities, tea tree oil can be applied topically to treat skin disorders like acne. Tea tree oil vapour inhalation therapy is helpful for respiratory ailments such as bronchitis, providing relief from inflammation within the respiratory tract.

But it's important to take into account any possible allergies and negative effects related to tea tree oil. Among the potential side effects are mainly skin irritation and allergic reactions. Moreover, swallowing tea tree oil can cause major toxicity, such as pneumonitis and depression of the central nervous system.

In summary, tea tree oil is a useful natural treatment for a variety of inflammatory disorders due to its anti-inflammatory qualities, which are based on its distinct chemical composition. Scientific research backs up the effectiveness of tea tree oil but more research is needed, and it's very important to take caution and be aware of any potential negative effects.