Life Extension Magazine®
Red blood cells and inflammation cells being maintained through PRMs

Resolve Persistent Inflammation

Chronic inflammation underlies many diseases of aging. Pro-resolving mediators (PRMs) resolve inflammation, returning tissues to their healthy state.

Scientifically reviewed by: Dr Gary Gonzalez, MD, on July 2021. Written By Randall Miller.

Acute inflammation is an important part of the body’s response to injury or infection. But when that inflammation does not resolve and becomes chronic, it causes major problems.

Man holding back due to acute and chronic inflammation

Chronic inflammation contributes to accelerated aging and almost all forms of persistent age-related disorders, including cancer, cardiovascular disease, and dementia.1,2

Many compounds can reduce and lower the fires of inflammation. But scientists have discovered a group of unique compounds produced in the body that are required for the resolution of inflammation.

These compounds, called pro-resolving mediators or PRMs, can help return inflamed tissues back to their healthy state, resolving inflammation and its harmful long-term effects.

PRMs are a family of naturally occurring lipid mediators, sometimes also referred to as Specialized Pro-resolving Mediators (SPMs).

A recent article in the journal BioFactors examined the scientific and medical literature on PRMs, including evidence that they may help fight infection.3

Inflammation and Resolution

Infographic of injury and acute inflammation response

Acute inflammation is the body’s immune response to an immediate threat or injury, including tissue damage, irritation, toxins, and infections.

“First responder” immune cells enter the affected area from the bloodstream, working to eliminate the threat and defend the body from further harm.

After that, the inflammation should resolve.

However, inflammation does not always stop on its own. Instead, it can enter a longstanding “limbo” state and become chronic inflammation, doing damage for months or years to come.

This chronic inflammation underlies many diseases, such as diabetes, heart disease, cancer, and overall aging.4,5 Reducing inflammation throughout the body is helpful but not enough to completely restore health. Inflammation needs to be resolved.

Resolution of inflammation is a complex, active process guided by specific signaling compounds produced in the body.6,7 Among these compounds are pro-resolving mediators (PRMs).

PRMs are different from anti-inflammatories. They do not simply reduce inflammation—they begin and guide the resolution of inflammation. They play an important role in getting tissues back to their healthy, functional state.8

Without adequate PRMs, inflammation can persist and do great harm.9,10

Types of PRMs

For years, it has been known that omega-3 fatty acids found in fish oil have anti-inflammatory properties, but it was not fully understood why.

As it turns out, PRMs are fat- or lipid-based compounds. They are produced from oily substances, including the omega-3 fatty acids found in fish oils (such as DHA and EPA).

Adequate intake of these omega-3s is required for the production of adequate levels of PRMs in the body.

There are a number of different PRMs produced in the body:3,8

  • E-series resolvins are produced from EPA.
  • D-series resolvins, protectins, and maresins are all produced from DHA.
  • Lipoxins are synthesized from an omega-6 fatty acid known as arachidonic acid.

What PRMs Do

While each specific PRM has slightly different actions, they overlap and complement each other. Together, they help coordinate many of the processes involved in inflammation resolution.

PRMs resolve inflammation and influence a healthy immune response by:3,8

  • Stopping the recruitment and migration of immune cells involved in acute inflammation,
  • Inhibiting the production of pro-inflammatory compounds by immune system and tissue cells,
  • Inhibiting the production of free radicals, used by immune cells in the fight against pathogens but which, if they persist, can cause tissue injury,
  • Stimulating macrophages to clean up tissues. Macrophages do this by devouring and destroying bacteria, allergens, dead immune cells, and other debris,
  • Increasing activity of immune cells that limit inflammation and then tidy up afterward, such as regulatory T cells,
  • Reversing hypersensitivity of nerve endings that was activated in acute inflammation, reducing pain,
  • Initiating repair and regeneration of damaged tissue, and
  • Returning blood flow and blood vessels to normal.

Fighting Infection

tooth and gum infection due to periodontitis and PRMs

Research has shown that PRMs may also help fight infections.11-29

In patients with severe periodontitis (a bacterial infection of the gums which can lead to tooth and bone loss), levels of PRMs were significantly lower in patients than in the control subjects.14 Their macrophage cells were less efficient at clearing bacteria.

This suggest that macrophages were less efficient at clearing bacteria as well as a protective role of SPMs in fighting infections.

Summary

Man holding knee and using PRMs to resolve inflammation

Short-term inflammation is vital to fight infection, injury, and disease.

Once the threat has passed, compounds called pro-resolving mediators (PRMs) help resolve that inflammation, preventing it from becoming chronic and thus guiding the return of tissues to their healthy state.

What you need to know

PRMs and Inflammation

  • Acute inflammation is an immune-system response to tissue injury, irritation, or infection.
  • If inflammation lingers, it can become chronic inflammation, which is an important factor in aging and increases risk for practically every age-related chronic disease.
  • Compounds known as pro-resolving mediators (PRMs) help resolve inflammation.
  • PRM precursors have been shown to increase blood levels of PRMs.

If you have any questions on the scientific content of this article, please call a Life Extension® Wellness Specialist at 1-866-864-3027.

References

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  2. Furman D, Campisi J, Verdin E, et al. Chronic inflammation in the etiology of disease across the life span. Nat Med. 2019 Dec;25(12):1822-32.
  3. Sandhaus S, Swick AG. Specialized proresolving mediators in infection and lung injury. Biofactors. 2021 Jan;47(1):6-18.
  4. Franceschi C, Campisi J. Chronic inflammation (inflammaging) and its potential contribution to age-associated diseases. J Gerontol A Biol Sci Med Sci. 2014 Jun;69 Suppl 1:S4-9.
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