This post is part of a series that dissects what kinds of inflammation people get, the diseases and risks associated with such inflammation, and how we could dial it down.
What is Interleukin-8?
Interleukin 8 (IL-8) is a ‘chemokine’ produced by various immune cells. Chemokines attract other immune cells to a specific area. IL-8 an important part of our immune response [1].
IL-8 attracts other cells that are the real muscle of the immune system: neutrophils (also attracts eosinophils and basophils). Neutrophils consume bacteria by engulfing them. IL-8 can release molecules like histamine to facilitate the attraction of neutrophils [1].
IL-8’s Role in Disease
IL-8 is also known to be a potent promoter of angiogenesis, which is the growth of blood vessels. This is what helps cancer grow. It also increases the proliferation and survival of cancer cells [1]. Indeed, increased IL-8 is associated with many cancers. Recently, IL-8 was shown to increase hormonal activity in prostate cancer cells (which helps them grow). IL-8 can also cause resistance to chemotherapy in cancer cells [2].
IL-8 contributes to forming plaques in our arteries [3]. TNF, IL-1b, and IL-8 enhance the binding of cholesterol (LDL) to blood vessels and increases the adhesion of immune cells in these vessels. Both of these events contribute to atherosclerosis [4].
Important Contributory Factors
Oxidative stress increases IL-8 and this also helps IL-8 recruit neutrophils [1].
IL-8 is released by fat cells and is elevated in obese people and correlated with fat mass [3].
IL-8 and the Brain
Higher IL-8 predicted smaller gray matter volumes in the hippocampus [5].
IL-8 also exerts neuroprotective properties [6]. IL-8 might be involved in the biological mechanisms mediating resilience to anxiety. In this way, it can reduce suicide among people with psychiatric conditions [6].
Diseases Associated With IL-8
- Heart disease [7]
- Cancer [2] – Prostate Cancer [2], Breast Cancer [8], Colorectal Cancer [9], Liver Cancer, Thyroid Cancer [10], Myeloma [11], among others.
- Pain [12, 13]
- CFS (post infection type) [14] and Fibromyalgia [15]
- Depression [16], Bipolar (could be from lithium) [17], Schizophrenia [18] – Also, children had a higher risk for schizophrenia when pregnant mothers had elevated IL-8 [19]. High IL-8 reduced the likelihood of positive responses to antipsychotic medication [20].
- Migraines [21]
- Alzheimer’s [22]
- IBS [23], Colitis [24], Crohn’s [25]
- Thyroiditis [10]
- Rheumatoid Arthritis [26, 27]
- Multiple Sclerosis [28], Lyme [29], ALS [30]
- Behcet’s [31]
- Asthma and COPD [32], Allergic Rhinitis [33] (not the main cytokine)
- Sleep apnea [34] – probably elevated because of hypoxia
- Osteoporosis (post-menopausal) [35]
- Psoriasis [36] and Eczema [37]
- Gingivitis [1]
- Vitiligo [38]
Top Ways to Inhibit IL-8
IL-8 production is caused by the transcription factor NF-κB, [1] and is induced by IL-1 [39] and TNF [40]. So anything that will inhibit these will also likely lessen IL-8.
- Calorie Restriction [5]
- Fasting [41]
- Wim Hof Breathing/Meditation [42]
- Quercetin [43, 44, 45, 46, 47]
- Bromelain [48] (promising, removes receptors – CD128a+b from neutrophils – unique mechanism?)
- Probiotics: B. infantis, L. casei and L. lactis [49], B. Longum, L. Bulgaricus [50], S. Boulardii [51], B. subtilis [51]
- Resveratrol (500mg, with 5g leucine) [52]
- Luteolin [38, 53]
- Apigenin [54]
- Aspirin [40]
- Cinnamon [55]/Sodium Benzoate
- Fisetin [56], not activated basophils [57]
- Cod liver/fish oil [58]
- Licorice [59]
- Curcumin [60]
- Black Cumin Seed Oil/Thymoquinone [61]
- Andrographolide [62] (by inhibiting NF-kB)
- Vitamin D3 [63]
- Jasmine Tea/EGCG
- Zinc [64]
- Red Yeast Rice/Statins [65]
- Theaflavins [66] (“Potent”)
- Artemisinin [67]
- Vitamin E [68] (alpha-tocopherol prevents UVA-induced IL-8 increase)
Hormones
- Cortisol/Glucocorticoids/Dexamethasone [69]
- alpha-msh [70]
- ACTH [70]
- DHEA [71]
- Progesterone [72]
- Estradiol [73] – in cystic fibrosis
Others
- LLLT [74, 75, 76]
- ACE inhibitors [77] – blood pressure lowering drugs. Many natural products are also ACE inhibitors.
- Theanine [78] (via NF-kB)
- Rutin [79]
- Milk thistle/Silymarin [80]
- Phytic acid [81] – in plant-based foods
- Oat [82]/Oat polyphenols [83]
- Ginkgo [84]
- Grape Seed Extract [85]
- Parthenolide/Feverfew [86] – (via inhibiting NF-kB, TNF, and IL-1b)
- Echinacea [87], Danshen [88], Kaempferol [56], Chrysin [56], Caffeic acid [89], Sumac [90],
- Doxycycline [91]
IL-8 Increasers
- Oxidative stress [92] (specifically, H2O2) – but H2O2 inhibits IL-8 production in neutrophils [93]
- Sun/UVB [94] + UVA [68]
- Exercise [95] – small and only locally in muscle.
- Obesity [3] – IL-8 is released by fat cells.
- Smoking [96]
- Estradiol [97] – in breast tissue
- Salmonella [49]
- Angiotensin II [77]
- Homocysteine [22]
Supplements:
- Lithium [98] (in intestinal cells)
- Jo’s Resistant starch/Butyrate [99] (intestinal cells)
- Asian Ginseng (some parts) [100]
No Effect
- Oleuropein [54]
- Myricetin [101]
