The following plant-derived compounds have shown an ability to help rescue the immune system from senescent decline:
- Reishi mushrooms
- Pu-erh tea
Together, these natural extracts help combat immune senescence by several complementary mechanisms that include enhancing activity of natural killer cells and T cells and turning down overactive immune reactions.
This article describes research supporting the use of low-cost plant extracts to help support immune health.
Reishi Mushrooms Extract
The immune-boosting properties of Reishi mushrooms have been appreciated in Eastern medicine for thousands of years. Modern science is now validating their health-promoting properties.1,2
Studies show that consuming these mushrooms improves immune function and has anti-tumor effects.2-9
In mice, Reishi has been found to promote the maturation and activation of immune system cells such as T cells, natural killer cells, dendritic cells, and macrophages.3-6
Lab studies show that Reishi also helps raise protective IL-10 levels and lower pro-inflammatory IL-6 levels.10,11
This indicates that Reishi augments the function of both the innate and adaptive immune system.
The innate immune system can be thought of as the body’s first line of defense, responding rapidly to potentially harmful insults such as viruses, bacteria, and cancer cells.
Natural killer cells are an important component of this innate immunity.12-17 The diminished activity of natural killer cells that occurs with aging predisposes the elderly to high rates of infection by viruses ranging from influenza to various herpes viruses.16-21
The adaptive immune system responds more slowly than the innate immune system but mounts a more specific, powerful attack against pathogens using specialized immune system cells called T cells.
With its ability to boost components of both innate and adaptive immunity, Reishi can protect the aging body from infections. This benefit has been borne out in laboratory studies demonstrating activity against many common viruses, including:
- Herpes simplex viruses—which cause oral and genital herpes22
- Influenza viruses—which cause the flu23
- Epstein-Barr virus—which causes mono- nucleosis but can also contribute to the formation of cancer24,25
- Hepatitis B virus—a common cause of liver disease that can lead to liver failure26,27
- Human immunodeficiency virus (HIV)— the virus which causes AIDS28,29
Premature Death of Jack LaLanne Likely Caused by Immune Senescence
It is impossible to overstate the magnitude of disability and death that immune senescence inflicts on aging human populations. When you hear a person died from “old age,” in almost every instance the underlying culprit is a dysfunctional immune system that ignites deadly inflammatory fires while failing to protect against infections and malignancies.
No one we know tried to live for over 100 years more than health pioneer Jack LaLanne. He engaged in rigorous lifelong exercise and ate a low-calorie healthy diet. He followed an old-line supplement program probably devoid of vitamin K and DHEA, which may have contributed to his premature death at age 96.
Jack LaLanne died of pneumonia following aortic valve surgery. Aortic valve stenosis is caused by calcification, chronic inflammation, and other factors such as elevated homocysteine.31
Vitamin K prevents calcification that is so often the reason why an elderly person’s aortic valve fails.32-37 DHEA partially protects against inflammation.38-40
Immune senescence may very well have contributed to Jack LaLanne’s early demise by crippling his ability to fight off the pneumonia, which was the acute cause of his death.
It is difficult to imagine someone as fit and vigorous as Jack LaLanne succumbing to pneumonia. Yet a dysfunctional immune system deprives even the hardiest of us from warding off infections that were easily overcome in our youth.
Clearly, protecting against immune senescence is a mandatory component of a longevity program.
In addition to supporting protection from infection, Reishi exhibits anti-cancer properties as well—largely because of its ability to enhance immune function.
In particular, the boost Reishi gives to natural killer cell, T cell, and macrophage function aids in the identification and destruction of abnormal cells that may develop into cancer.2,9
Reishi may also directly combat tumors through an array of mechanisms it has demonstrated in the lab: impairing the ability of tumor cells to grow, preventing tumor blood vessels from developing, starving the abnormal cells, and even directly killing cancer cells.2,9
In one study, Reishi mushrooms were applied to various human cancer cell lines.9 Not only did the Reishi reduce the growth of the cells, but it induced cell death in many of the diseased cells.
Perhaps most impressively, Reishi has been shown to significantly extend lifespan of mice.30 Researchers followed two groups of mice, one fed a normal control diet and the other fed a diet enriched with a Reishi extract.
The Reishi supplemented group lived as much as 148 days longer than the control group. Given that the lifespan of a mouse is typically less than two years, this represents a dramatic increase in longevity.
WHAT YOU NEED TO KNOW
Boosting the Aging Immune System
- Older age is associated with a decline in immune system function, known as immune senescence.
- Immune senescence increases the risk for infections, cancer, autoimmune disease, and chronic inflammatory conditions.
- Certain plants and fungi have been found to bolster immune system cells and functions, improving immunity.
- Reishi mushrooms, Cistanche, and Pu-erh tea have all been shown to improve immune function by various complementary mechanisms.
- Intake of extracts of these plants and fungi may help restore immune function, reducing the risk for infection, cancer, and other conditions for which the elderly are at increased risk.
Cistanche is a type of desert plant that, like Reishi mushrooms, has long been appreciated for its medicinal uses in Eastern medicine.
Several studies have confirmed the ability of Cistanche extract to boost immune cells in the body.41-44
In one study, researchers utilized a strain of senescence-accelerated mice. These mice age more rapidly than normal mice and display the same deterioration in immune function seen in human immune senescence.
The mice fed a diet supplemented with Cistanche extract for four weeks had a significantly increased number of T cells and natural killer cells in the blood, and lower pro-inflammatory interleukin-6 (IL-6) levels.
This enhancement in immune function translated to an extended lifespan as well. The average age after supplementation with Cistanche was 15% longer than the controls’.41
In addition to T cells and natural killer cells, Cistanche also helps activate other important immune cells, including macrophages, dendritic cells, and B cells.42,43
Encouraging results have been demonstrated in a human study as well. When elderly subjects took 100 mg of Cistanche extract daily for 12 weeks, there was a 6.1% increase in helper T cells and an almost 12% increase in natural killer cell activity. This increase represents an immune-boosting effect.44
Patients also experienced improved markers of vascular function and a decrease in fatigue. No significant adverse effects were observed.
Given that these same improvements in immune function resulted in enhanced longevity in animal studies, it can be hoped that the rejuvenating effect Cistanche has on the human immune system may assist in prolonging lifespan in people as well.
A hallmark marker of longevity potential is blood levels of interleukin-6 (IL-6).
Older individuals with higher levels of IL-6 tend to not live as long and tend to have a higher burden of chronic disease. On the other hand, older people with lower IL-6 levels tend to be healthier and have better prospects for even longer lives.
This makes sense because elevated IL-6 generates chronic inflammatory signals that result in tissue damage throughout the body.45-49
THE IMMUNE SYSTEM
How Our Immune Cells Defend Us
Natural killer cells are the body’s first responders against viral infections and cancer cells, and play an important role in battling bacterial and fungal infections.12-17 The age-related decline in the function of natural killer cells leads to higher rates of many viral, bacterial, and fungal infections—and these infections are more likely to be serious in those with age-related immune senescence.19-21
For example, research shows that the common cold (which is caused by a virus) is more frequent in individuals with low natural killer cell function—and conversely, that greater natural killer cell function helps protect against viral outbreaks.16-18
The decline in natural killer cell activity has also been shown to increase the rates of viral infections, including viruses that cause influenza and viruses in the herpes family.19 These include cytomegalovirus (CMV), Epstein-Barr virus, varicella zoster (which causes chicken pox and shingles), and herpes simplex viruses (causing oral and genital herpes).
Compounding the problem, cytomegalovirus (CMV) itself may directly contribute to the loss of immune function.54,55 In one study, higher levels of CMV in older women correlated with an increased five-year risk of all-cause mortality.56
A Breakdown in the Body’s Targeted Killers
T cells are targeted killers that are part of the body’s adaptive immunity. If any infections go undetected by the natural killer cells, T cells are the “big guns” that step in and eliminate the infected cells.
These cells hunt down specific targets and stage a powerful attack to eliminate them once the enemy has been identified.
T cells contribute to long-term immunity, the phenomenon in which the body “remembers” an antigen (a virus, bacteria, or even a vaccine). That way, if an individual is later exposed to the same virus, bacteria, or antigen, the immune system is primed to destroy it more quickly in the future—often before any signs of the disease occur.
Pu-erh Tea Extract’s Immune Effects
A fermented black tea called Pu-erh has shown benefits for the aging immune system.50
Studies show that Pu-erh tea and its extract combat immune senescence by multiple mechanisms.50 Two of the chief ones include increasing natural killer and T cells.
In addition to its ability to bolster the immune system itself, Pu-erh tea appears to provide direct antibacterial and antiviral effects as well. Several studies have demonstrated that Pu-erh tea directly kills or inhibits the growth of bacteria and suppresses the growth of viruses such as hepatitis B.50
In one investigation, scientists studied the effects of Pu-erh tea on the senescence-accelerated strain of mice discussed previously.51
Before supplementation with Pu-erh tea, the mice demonstrated the same features of immune system deterioration seen in aging humans, including lower numbers of active T cells and natural killer cells.
In addition, levels of the powerful pro-inflammatory cytokine IL-6 were markedly elevated in the senescence-accelerated mice, compared with controls.
Feeding these mice with Pu-erh tea reversed these markers of immune senescence.
The treated mice experienced enhanced numbers of T cells and natural killer cells and a significant 43% decrease in IL-6—benefits that more closely resemble a normal, healthy immune system.
Based on these immune-boosting results, the researchers concluded that intake of Pu-erh tea may help older individuals prevent infection and cancer.
Anti-Inflammatory Effects in Humans
A human study of Pu-erh tea extract further demonstrated its role in reversing inflammatory cytokine levels.
The study was performed among a group of patients with metabolic syndrome, a common condition defined by central obesity, borderline or high fasting glucose, high blood pressure, and elevated blood lipids.52 Those with metabolic syndrome have higher levels of inflammation and are at an increased risk of having immune impairments.53
Subjects were given either Pu-erh tea extract twice daily or a placebo. They were instructed to exercise and observe a healthy diet during the study period but were permitted no medicines that might otherwise affect the results.
After three months, patients provided blood samples for analysis of inflammatory cytokines and other markers of inflammation.
As expected, placebo recipients showed no significant changes in blood levels of TNF-a or IL-6 (pro-inflammatory cytokines), IL-10 (an anti-inflammatory cytokine), or C-reactive protein (CRP, a marker of total body inflammation).
Subjects supplemented with Pu-erh tea extract showed improvements in immune status as follows:
- 21% reduction in IL-6,
- 23% reduction in TNF-a, and
- 26% reduction in CRP.
These reductions indicate significant decreases in overall pro-inflammatory status.
This study also found a 34% increase of inflammation-quelling IL-10, which further demonstrates the overall reduction in inflammation possible with Pu-erh tea extract.
Pu-erh tea extract offers multiple pathways to potentially prevent progress of immune senescence.
Immune senescence occurs as people age and puts the elderly at increased risk for infections, cancers, and a variety of chronic inflammatory diseases.
Compounds naturally found in certain plants and fungi bolster weakened immune systems.
Reishi mushrooms, Cistanche, and Pu-erh tea can improve immune function by several complementary mechanisms, including amplifying the activity of natural killer cells, T cells, and various other immune system components.
They also help suppress over-activity of immune cells that can result in damaging inflammatory reactions.
Adding these nutrients to a healthy diet can help induce improvements in immune cell markers in older age.
If you have any questions on the scientific content of this article, please call a Life Extension® Wellness Specialist at 1-866-864-3027.
Reprinted with permission of Life Extension®- Originally published in the July 2020 issue
Read the original article on Life Extension’s website – https://www.lifeextension.com/magazine/2020/7/combat-immune-senescence
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