ADVERTORIAL
Gut endotoxins in anxiety and depression : a potential role for lavender oil
By Samuel Peters | BHSc ( Naturopathy )
Article highlights
• Inflammation is an increasingly recognised pathophysiological factor in depression and anxiety
• Numerous studies have found that increased intestinal permeability and the subsequent endotoxaemia can be a significant driver of inflammationinduced mood disorders
• Recent research suggests that the anxiolytic and antidepressant effects of lavender extend beyond neurotransmitter modulation and may also be mediated via its antiinflammatory activity
Gut-induced inflammation in mood disorders Inflammation is an increasingly recognised pathophysiological factor in depression and anxiety . The first observation of peripheral immune involvement in mood disorders was published in the late 1980s . It reported psychiatric complications in a subset of patients suffering from chronic viral hepatitis who were treated with inflammation-inducing interferon-α . 1
In the decades since , multiple clinical and preclinical studies have associated high levels of circulating leukocytes and proinflammatory cytokines with depressive and anxiety symtpoms . 1 Recently , certain anti-inflammatory drugs , such as ketamine , are being accepted as a mainstream approach for treatment-resistant depression .
A growing body of research suggests that translocation of bacteria or its byproducts from the gut microbiota to blood circulation , as a result of intestinal permeability , may be a significant underlying driver to the peripheral and central inflammation associated with mood disorders . 2
Clinical studies Emerging research is beginning to untangle this complex relationship . One study demonstrated that both the prevalence and median values of serum antibodies against the lipopolysaccharides of six enterobacteria were greater in depressed patients than controls . 3 In another study , major depressive disorder ( MDD ) patients had elevated expression of bacterial DNA , indicative of bacterial translocation , compared to nondepressed controls , and the magnitude was correlated with depressive symptom severity . 4
Other studies have found that the levels of immunoglobulins were significantly higher in depressed patients compared to healthy controls and that significantly higher IgM responses were observed in patients suffering from chronic depression ( duration > 2 years ) when compared to patients with non-chronic depression and controls . This suggests that patients with chronic depression may have increased intestinal permeability and to a larger extent than non-chronic patients . 5
GI inflammation and increased intestinal permeability may play also a significant role in suicidal symptomatology . In a recent pilot study it was demonstrated that recent suicidal attempters ( within the last month ) in the course of major depression , bipolar disorder and schizophrenia had increased IgA to lipopolysaccharides compared to a healthy control group . 5
Clinical symptoms A human clinical study found that the characteristic features of mood disorders associated with endotoxaemia include ; fatigue , sadness , autonomic and gastrointestinal symptoms , muscular tension , and a subjective feeling of infection . In patients who present with such symptom picture , an inflammatory pathophysiology induced by intestinal permeability and endotoxin translocation should be suspected . 3
The broad mechanisms of lavender oil Multiple human clinical trials have demonstrated that administration of oral lavender oil is effective for improving symptoms of mood disorders including anxiety and depression . Its clinical effects are thought to be mediated via modulation of voltage operated calcium channels ( VOCC ). Elevated calcium channel activity can contribute to increased release of excitatory neurotransmitters , including glutamate and norepinephrine . Furthermore , lavender oil has been shown to reduce 5-HT1A binding potential leading to increased serotonin levels . 6
However , recent research suggests that the anxiolytic and antidepressant effects of lavender extend beyond neurotransmitter modulation and may also be mediated via its anti-inflammatory activity . 7 In vitro and in vivo research has found that lavender inhibits the inflammation induced by bacterial endotoxins , 8 and reduces nitric oxide- and histamine-mediated inflammatory responses . 9
Clinical summary While lavender oil may help to inhibit inflammation induced by gut derived endotoxins , clinicians should also focus on restoring the underlying gut barrier dysfunction and dysbiosis through the use of prebiotics such as Partially Hydrolysed Guar Gum , broad spectrum probiotics and gut healing agents such as glutamine and n-acetyl-glucosamine , in combination with sustainable anti-inflammatory eating habits .
Disclaimer : The views and opinions expressed in these advertorials are those of the authors and do not necessarily reflect the opinions of ATMS or its Directors .
238 | vol27 | no4 | JATMS