Do cytokines play a role in depression?

Mounting evidence indicates that inflammatory cytokines contribute to the development of depression in both medically ill and medically healthy individuals.

How are cytokines linked to depression?

A risk factor like acute or chronic stress could, for example, lead to an increased production of pro-inflammatory cytokines (115, 138–140), and these cytokines could then enter the brain (31) and lead to changes in neurotransmitter systems involved in the development of depression, such as the serotonin system (82, 83 …

What are the strongest risk factors for late life depression?

After simultaneous multivariable-adjustment, multiple factors in the domains of social stress (lower self-rated societal position and high volume of caregiving to disabled/ill relatives), unfavorable lifestyle (smoking, physical inactivity, heavy or binge drinking), and poor physical health (multiple comorbidity burden …

How do cytokines affect the brain?

Through their effects on neurotransmitter systems, cytokines impact neurocircuits in the brain including the basal ganglia and anterior cingulate cortex, leading to significant changes in motor activity and motivation as well as anxiety, arousal, and alarm.

What is the cytokine hypothesis of depression?

The ‘cytokine hypothesis of depression’ implies that proinflammatory cytokines, acting as neuromodulators, represent the key factor in the (central) mediation of the behavioural, neuroendocrine and neurochemical features of depressive disorders.

What is cytokine release syndrome?

A condition that may occur after treatment with some types of immunotherapy, such as monoclonal antibodies and CAR-T cells. Cytokine release syndrome is caused by a large, rapid release of cytokines into the blood from immune cells affected by the immunotherapy.

What age is Late life?

Late-life depression refers to a major depressive episode occurring for the first time in an older person (usually over 50 or 60 years of age). The term can also include depression that develops in an older person who suffered from the illness earlier in life.

What are functional consequences of late life depression?

Untreated late-onset depression can lead to increased mortality, decreased quality of life, increased healthcare needs, and less ability to perform activities of daily living among older adults.

What triggers the release of cytokines?

During infection, bacterial and viral products, such as bacterial lipopolysaccharide (LPS), cause the release of cytokines from immune cells. These cytokines can reach the brain by several routes. Furthermore, cytokines, such as interleukin-1 (IL-1), are induced in neurons within the brain by systemic injection of LPS.

Are cytokines good or bad?

Cytokines may be “good” when stimulating the immune system to fight a foreign pathogen or attack tumors. Other “good” cytokine effects include reduction of an immune response, for example interferon β reduction of neuron inflammation in patients with multiple sclerosis.

How are cytokines used to treat major depression?

Concerning the deficiency in serotonergic (5-HT) neurotransmission that is concomitant with major depression, cytokines may reduce 5-HT levels by lowering the availability of its precursor tryptophan (TRP) through activation of the TRP-metabolising enzyme indoleamine-2,3-dioxygenase (IDO).

How does chronic stress affect the cytokines in the body?

Chronic stress acts via physical signals such as danger-associated molecular patterns (DAMPs) to increase cytokine-mediated messages that eventually lead to depression and other medical diseases.

How does high levels of inflammatory cytokines affect the brain?

High levels of inflammatory cytokines activate some neurotransmitter pathways which reduce growth factor concentrations while producing changes in monoamines, glutamate, and other peptide transmitters.

How are cytokines produced in the immune system?

Cytokines can enter the brain via several pathways and recruit both endothelial and immune cells to produce more local cytokines, amplifying the effect on the brain.