What is neuroinflammation?
Neuroinflammation is inflammation of the central nervous system (CNS), which includes our brain and spinal cord. This “fire” in the brain is usually set up elsewhere in the body but manages to break through the wall that protects the brain and spreads the fire to the brain. More and more research has shown that neuroinflammation can affect our mood and is a significant contributing factor to numerous psychological and neurodegenerative diseases.
Symptoms of neuroinflammation
Brain fog
Anxiety
Depression
Loss of memory
Declined cognitive function
Chronic pain - Inflammatory pain (e.g. arthritis), cancer pain, neuropathic pain (e.g. pain following stroke, brain trauma, nerve injury)
Contributing factors & causes of neuroinflammation
Brain injury/trauma, brain surgery
Autoimmunity
Physical and psychological stress
Infections, pathogens (How Chronic Infections Affect Our Body)
Environmental toxins (Toxins - Why Should We Care?)
Food allergy & intolerance
Leaky gut, dysbiosis
Poor diet
These factors can set off or aggravate neuroinflammation by a direct contribution of oxidative stress and inflammation or by altering the brain chemistry. A lot of the time, it also involves the mechanism of damaging the blood-brain barrier (BBB) and exposing the brain to external insults.
The BBB separates our central nervous system (CNS) from the peripheral blood circulation and protects our brain from inflammatory mediators, oxidants, or toxins in the periphery. However, infections, dysbiosis, leaky gut, stress, and environmental toxins can generate pro-inflammatory mediators and oxidative stress, which can damage and decrease the integrity of the BBB. When this barrier is broken down, pro-inflammatory cytokines, oxidants, and toxins can enter the brain and cause inflammation and neurological damage.
A poor diet (e.g.: high fat, high sugar, high refined carbohydrate diet), alcohol, diabetes, and obesity, can also cause systemic inflammation, break down the BBB and trigger neuroinflammation.
Health conditions related to neuroinflammation
Major depressive disorder
Schizophrenia
Bipolar disorder
Attention deficit hyperactivity disorder (ADHD)
Autism spectrum disorder
Obsessive-compulsive disorder
Parkinson’s disease
Alzheimer’s disease
Multiple sclerosis
Neuroinflammation can cause degeneration of the nervous system, mood disturbances, and impairment of our cognitive, behavioral, and psychiatric functions by:
Altering the brain chemistry (e.g.: glutamate metabolism and the function of glutamate transporters are altered in neuroinflammation).
Disrupting the normal function of BBB (causing leaky brain) and resulting in increased oxidative stress and inflammation of the CNS.
Disrupting the normal function of the hypothalamus-pituitary-adrenal axis (HPA axis).
The HPA axis regulates our body's response to stress. When it's dysregulated, our body is less capable of making adjustments in response to stress and we can see changes in our energy, mood, emotions, blood pressure, immune function, metabolism, hormones, and digestion.
Neuronal apoptosis - programmed cell death of neurons.
Synaptic impairment - impairment in the information exchange within the nervous system.
Putting out the fire
It’s important to put out the fire from its starting point instead of just dealing with the smoke (symptoms). A diet rich in anti-inflammatory and antioxidant foods, anti-inflammatory herbs like turmeric, and antioxidants like vitamins C, E, and glutathione are crucial in calming inflammation and reducing oxidative stress. On top of that, figuring out any underlying gastrointestinal problems, allergies, autoimmunity, and infections are also the key since they are often the starting point of the “fire.”
References
Tohidpour A, Morgun AV, Boitsova EB, et al. Neuroinflammation and Infection: Molecular Mechanisms Associated with Dysfunction of Neurovascular Unit. Front Cell Infect Microbiol. 2017;7:276. Published 2017 Jun 20. doi:10.3389/fcimb.2017.00276
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