The accumulation of all powers, legislative, executive, and judiciary, in the same hands, whether of one, a few, or many, and whether hereditary, self-appointed, or elective, may justly be pronounced the very definition of tyranny.
— James Madison, Federalist No. 48
In 2012, sales of adult diapers [in Japan] surpassed sales of baby diapers for the first time.
— from Code Red (Wiley, 2014)
by John Mauldin and Jonathan Tepper
It is hard to imagine a more stupid or dangerous way of making decisions than by putting those decisions in the hands of people who pay no price for being wrong.
— Thomas Sowell, economist, historian, philosopher
The Second Amendment is a doomsday provision, one designed for those exceptionally rare circumstances where all other rights have failed—where the government refuses to stand for reelection and silences those who protest; where courts have lost the courage to oppose, or can find no one to enforce their decrees. However improbable these contingencies may seem today, facing them unprepared is a mistake a free people get to make only once.
— Judge Alex Kozinski, Chief Judge,
U.S. Court of Appeals, 9th Circuit
I would never invade the United States. There would be a gun behind every blade of grass.
— Isoroku Yamamoto, commander
of Japanese naval military forces in WWII
When you see that trading is done, not by consent but by compulsion, When you see that in order to produce, you need to obtain permission from men who produce nothing, When you see that money is flowing to those who deal, not in goods, but in favors, When you see that men get richer by graft and by pull than by work, and your laws don’t protect you against them, but protect them against you, When you see corruption being rewarded and honesty becoming a self-sacrifice—you may know that your society is doomed.
— Ayn Rand, Atlas Shrugged (1957)
Everything that is right or reasonable pleads for separation. The blood of the slain, the weeping voice of nature cries, ’tis time to part.
— Thomas Paine, Common Sense (Jan. 9, 1776)
Quantity produces quality. If you only write a few things, you’re doomed.
— Ray Bradbury
IMAGINE THERE’S NO FDA
Imagine there’s no FDA
It’s easy if you try
No more illegal rules and regulations
No more they decide if you live or die
Imagine there’s no one there
Let the whole world declare
It’s up to you
To decide what you do
They’ve gone away
Imagine being free today.
As you may have read in earlier newsletters, Sandy had to undergo three operations for a life-threatening bowel obstruction about two years ago and lost about 2/3rd of her colon and 5 feet of her small intestine. Since the lower intestinal tract is importantly involved in absorbing water and minerals, among other things, a problem for people with “short bowel syndrome” is getting adequate quantities of certain nutrients that would normally be absorbed in the lower tract. (If too little water is reabsorbed from the intestinal fluids, for example, then you can have chronic diarrhea, which also causes losses of electrolytes. Indeed, Sandy’s sodium levels were low so she is now taking sodium chloride tablets to normalize that.)
So it was that we recently found out from routine lab tests that Sandy was remarkably deficient in iron (with reduced levels of red blood cells and hemoglobin, as well as a shockingly low transferrin saturation level of 4%). Transferrin is a protein that transports and stores iron and is supposed to be saturated in the range of 15 to 50%. Sandy’s local physician (head of our regional hospital) said that he didn’t know anybody could be walking around with such a low level of available iron! Sandy’s main problem that could definitely be attributed to low iron was a dramatic worsening of her restless legs syndrome symptoms.1 This disorder is known to be associated with inadequate iron supplies and it is hypothesized that deficiency of iron in dopamine-containing neurons in the brain may be a cause.2
Iron supplementation to the rescue! We have described an iron formulation we put together for our own personal use that has the tremendous advantage over other forms of iron in that it is very unlikely to cause stomach upset. She started with two capsules a day of the iron supplement (one capsule contains the RDA of iron) on Jan. 31, 2014. At that time, she had a measured iron level of 20 mcg/dL, whereas the normal range is 40–160 mcg/dL. As mentioned above, her transferrin saturation was 4%, only about 25% of the value at the low end of the normal range.
Today, March 28, 2014, her latest iron and transferrin measurements have come back, the blood having been drawn on March 14th. We (Durk and me as well as our doctor) were all amazed at the new numbers: her iron had increased to 229 and was now HIGH, so she has reduced her supplement to a single RDA level capsule of iron a day. Her transferrin saturation level had increased to 54%, which is slightly higher than the 50% upper end of the normal range. She will return for further testing in a few weeks. Her hemoglobin, which was 10.9 g/dL (with the normal range being 12.2–16.2 g/dL) as of Jan. 31st, had also increased to 12.5 and is now in the normal range.
Moreover, the improvement in her restless legs syndrome symptoms has been dramatic, with her need for dopaminergic agonist medications to control it reduced by about 80%.
The WI-38 human fibroblast is the cell line that Leonard Hayflick used in the discovery of the famous Hayflick limit, where he demonstrated that cells would replicate only a limited number of times before becoming terminally senescent.AA Senescent cells don’t immediately die but they no longer replicate and they undergo many changes that distinguish them from non-senescent cells. It has been learned, for example, that senescent cells are not generally beneficial to have around, other than the fact that their exit from the cell cycle acts as a protective mechanism against those cells becoming cancerous. A growing population of senescent cells with age has been found to have a deleterious effect on the functioning of non-senescent cells in their neighborhood by, for example, sustaining chronic inflammation and extracellular matrix remodeling.A The Hayflick limit was one of the earliest studies in which the processes that impair the function of aging cells started to be discovered.
Today, we report the publication of a new study (published today, Feb. 28, 2014 in the Journal of Biological Chemistry.1) describing how selenium depletion (Dpl) impairs the proliferative capacity of WI-38 cells and accelerates their conversion to senescence and how the cells could undergo additional doublings by being supplemented with selenium (Sup) beyond the amount of selenium considered adequate (Ctrl). The form of selenium used was sodium selenite, the form we recommend and take ourselves. [See “If You Take Selenium To Help Reduce Your Risk of Cancer …” in the October 2010 issue of Life Enhancement.]
The researchers first note that selenium levels decline with age and describe two independent studies that suggest a link between lifespan and selenium, finding that selenium levels in the blood of elderly people was a predictor of longevity2,3 The results of their new work1 showed that “the change in selenium concentrations in young cells triggers rapid changes in replicative senescence-associated markers and signaling pathways and regulates the entry into replicative senescence.”1
Consistent with prior studies, the researchers found that their cells grown in Ctrl (Control) conditions maintained their proliferative capacity until the level of population doubling #51 (CPD 51). At that time they showed signs of early senescence (presenescence) and they became senescent at CPD 57. The researchers separated cells that had reached CPD 36 (late middle aged) and were still actively dividing and exposed them to the different concentrations of selenium, finding that in two passages (two divisions) the effect of different concentrations of selenium was already apparent. Hence, these changes can take place fast at a late stage of replicative lifespan under the influence of either deficient selenium or selenium supplementation. In all cases, they reported, “selenium supplementation led to an extended replicative lifetime.”
The scientists examined changes in markers of senescence in young proliferating WI-38 fibroblasts in Dpl, Ctrl, and Sup media for two passages and found a nearly threefold increase in one such marker, SAHF, between the cells grown under Dpl conditions as compared to those grown in the Ctrl condition. Again, these changes were in response to different media selenium concentrations. The researchers propose that, “the entry into replicative senescence of cultured human diploid fibroblasts is due to an irreversible cell cycle arrest mainly controlled by the p53-p21 and p-16-pRb signaling pathways.”1Selenium supplementation was found to significantly reduce (by more than 3 times) the expression levels of p16, p21, p53, and pRb as compared with cells grown under Ctrl conditions.
Young WI-38 Cells Grown Under Conditions of Selenium Deficiency (Dpl) Look Like Senescent Cells
Very interestingly, the researchers found that the young WI-38 cells, after growing in Dpl media for two passages “present several characteristics very similar to those of senescent cells, which include morphological changes, increased number of positive cells for SAHF and SABG [biomarkers of senescence], and telomere length shortening.”1
Similarities in Senescent Cells and Cells Exposed to Chronically Elevated Levels of Oxygen
Another paper1B reports finding similar gene expression in senescent and chronic mild hyperoxic cells (cells exposed to higher than normal oxygen), suggesting that hyperoxia could be considered a model of accelerated senescence and, therefore, another good reason to avoid chronic oxidative stress as much as possible.
PREVENTING MUSCLE LOSS WITH AGING
Can Selenium Supplementation Prevent Age-Associated Sarcopenia?
A very recent paper4 reported that p16INK4a, a p16 tumor suppressor protein (part of the p16 signaling pathway), was responsible for inducing senescence in the regenerative capacity of muscle stem cells. These researchers found that p16INK4a, thought to be a master regulator of cellular senescence, is (as part of the p16INK4a/Rb/E2F-signaling axis) responsible for a senescent-like state that may be a key part of the process of sarcopenia, the age-associated loss of muscle. In the new study,4 the scientists found that genetically silencing p16INK4a expression restored self-renewal and proliferation in aged skeletal muscle satellite cells.
We wonder: Would selenium supplementation tend to reduce the expression of p16INK4a as it did the expression of p16 in the WI-38 fibroblast study discussed above? If so, selenium supplementation could be a practical means of protecting against sarcopenia.
Magnesium Deficiency Accelerates Cellular Senescence in Cultured Human Fibroblasts
According to this 2008 paper,4B more than half the population of the U.S. ingests an inadequate amount of dietary magnesium. The researchers cultured human diploid lung fibroblasts (IMR-90) in media containing various amounts of magnesium. Cells cultured in media with 50% of the magnesium contained in standard media were shown, in four independent lifespan studies, to lose 2.5 population doublings as compared with cells grown in media with the full amount of magnesium. Cells cultured in 13% of normal magnesium concentration lost 4.5 population doublings. [See “Durk Pearson & Sandy Shaw Ring the Bell for … Magnesium Aspartate” in the August 1998 issue of Life Enhancement.]
Is It Beneficial To Remove Senescent Cells?
Removing p16INK4a-positive senescent cells from experimental animals (mice) has already been done in order to see whether that might be beneficial (or not).6 In that study, mice with a progeroid genetic background were treated with an experimental drug to eliminate p16INK4a-positive senescent cells. The researchers reported that, “In tissues—such as adipose tissue, skeletal muscle, and eye—in which p16INK4a contributes to the acquisition of age-related pathologies, lifelong removal of p16INK4a-expressing cells delayed onset of these phenotypes. Furthermore, late life clearance attenuated progression of already established age-related disorders.” Hence, at least in this model, it would appear that senescent cells can be removed with beneficial effects.
p16INK4a Positive Cells in Human Skin Found to Reflect Biological Age
A powerful link between the p16INK4a senescence marker and biological age was reported in another new paper,7 when researchers found that a younger biological age associates with lower levels of p16INK4a positive cells in human skin. (The researchers were referring to chronological age as biological age, presumably due to the lack of a standardized way of distinguishing between them.) They observed that increased numbers of senescent cells were associated with age-related pathologies such as atherosclerosis, diabetes, and kidney disease. This makes it possible for a test to be developed in which one could find out how well he or she is doing in terms of aging through the detection of this senescence marker in their skin cells. (NOTE: The FDA is likely to try to block this information from being made available directly to the public. However, under the First Amendment, they do not have the authority to do so.)
Osteoarthritis Characterized by Accumulation of Senescent p16INK4a Positive Cells
A very common age-associated disease that has been linked to cellular senescence is osteoarthritis, which can be a source of considerable pain and disability. In a 2014 paper,A researchers reported that “[o]steoarthritis (OA) is characterized by the accumulation of chondrocytes expressing p16INK4a and markers of the senescence-associated secretory phenotype (SASP) including the matrix remodelling metallo-proteases MMP1/MMP13 and pro-inflammatory cytokines IL-8, and IL-6.” The researchers found that p16INK4a is induced by treatment with the pro-inflammatory cytokine IL-1beta and also during in vitro chondrogenesis.
Senescence Can Be Transmitted to Non-Senescent Neighboring Cells
It is interesting to note that recent studies cited in another paper9 have shown that “some SASP factors, including IL-1beta, can induce senescence in normal cells. Thus, senescence can be transmitted to untransformed neighboring cells through the paracrine activity of the SASP.”9 There goes the neighborhood! (Seriously, this is another reason to try to prevent the buildup of senescent cells during aging.)
Metformin May Be Another Anti-Senescence Treatment
In addition to selenium, magnesium, and zinc, there is also evidence that metformin, a drug used widely in the treatment of diabetes and symptoms of metabolic syndrome, such as insulin resistance, may also protect against the premature senescence that accompanies high glucose conditions.10 In a study of kidney cells (primary rat glomerular mesangial cells) in culture, exposed to high glucose conditions, researchers found that the cells initially and transiently entered a proliferative phase, but was followed by cell cycle arrest along with changes seen in senescent cells (for example, increased expression of cyclin-dependent kinase inhibitors p21(cip1) and p27(kip1)). In addition, connexin43, a gap junction that importantly allows cells to communicate with each other, is less expressed in cells exposed to high glucose conditions and in older cells. This decreased intercellular communication is also observed in senescent cells.10
AMPK, an important regulator of energy metabolism (increased under conditions of reduced energy availability, decreased when energy supplies are plentiful) is reported to maintain the expression of connexin43 under high glucose conditions. Incubation of the rat glomerular mesangial kidney cells with metformin in this study10 significantly increased p-AMPK (phosphorylated AMPK, the active form) and up-regulated connexin43 compared to cells exposed to high glucose conditions but not treated with metformin. Metformin treatment also decreased the expression of the senescence markers p27(kip1) and p21(cip1).
Too Much Zinc May Worsen Osteoarthritis
A caution concerning zinc supplementation: A 2014 Cell paper11 reported that ZIP8, a zinc transporting enzyme, is overexpressed in chondrocytes (cartilage cells) of humans with osteoarthritis. This caused increased intracellular levels of zinc and of zinc-dependent metalloprotease matrix-degrading enzymes that have been identified as causative factors in osteoarthritis. The question is: could zinc supplementation in those with osteoarthritis have an exacerbating effect on the disease? The authors11 speculate that local depletion of zinc, inhibition of ZIP8 or of the metalloproteases involved in osteoarthritis might be effective therapies for osteoarthritis. Also, we note, reducing IL-1beta (which induces ZIP8) is another possible therapeutic approach. (IL-1beta is an important part of the human wound-healing response.11A)
How old would you be if you didn’t know how old you are?
— Leroy “Satchel” Paige
AA. Hayflick. The limited in vitro lifetime of human diploid cell strains. Exp Cell Res. 37:614-36 (1965).
A. Philipot et al. p16INK4a and its regulator miR-24 link senescence and chrondrocyte terminal differentiation-associated matrix remodeling in osteoarthritis. Arthritis Res Ther. 16:R58 (2014).
1. Legrain et al. Interplay between selenium levels, selenoprotein expression, and replicative senescence in WI-38 human fibroblasts. J Biol Chem. 289:6299-310 (2014).
1B. Saretzki et al. Similar gene expression pattern in senescent and hyperoxic-treated fibroblasts. J Gerontol. 53A(6):B438-42 (1998).
2. Ray et al. Low serum selenium and total carotenoids predict mortality among older women living in the community. The women’s health and aging studies. J Nutr. 136:172-6 (2006).
3. Akbaraly et al. Selenium and mortality in the elderly. Results from the EVA study. Clin Chem. 51:2117-23 (2006).
4. Sousa-Victor et al. Geriatric muscle stem cells switch reversible quiescence into senescence. Nature. 506:316-21 (2014).
4B. Killilea and Ames. Magnesium deficiency accelerates cellular senescence in cultured human fibroblasts. Proc Natl Acad Sci USA. 105(15):5768-73 (2008).
5. Li and Belmonte. Genetic rejuvenation of old muscle. Nature. 506:304-5 (2014). This is the commentary on paper #2.
6. Baker et al. Clearance of p16INK4a-positive senescent cells delays ageing-associated disorders. Nature. 479:232-6 (2011).
7. Waaijer et al. The number of p16INK4a positive cells in human skin reflects biological age. Aging Cell. 114:722-5 (2012).
9. Salama et al. Cellular senescence and its effector programs. Genes Dev. 28:99-114 (2014).
10. Guo et al. AMPK-mediated downregulation of connexin43 and premature senescence of mesangial cells under high-glucose conditions. Exp Gerontol. 51:71-81 (2014).
11. Kim et al. Regulation of the catabolic cascade in osteoarthritis by the zinc-ZIP8-MTF1 axis. Cell. 156:730-43 (2014).
11A. Kraus. The zinc link. Nature. 507:441-2 (2014).
The Triage Theory of Aging: Why Modest Inadequacy of Vitamins or Minerals May Increase Diseases of Aging Later
An interesting and potentially very important new theory of aging1–3 posits that, while modest inadequacies of vitamins or minerals may not appear to cause short-term negative effects (such as reduced survival), in the long run they may be the basis for insidious effects such as increased risk of age-related degenerative diseases. This theory may be important for explaining how the widespread modestly inadequate intake of many vitamins and minerals in the United States and other advanced industrialized countries results, in association with the increasing lifespan in those countries, with more people at risk for age-related degenerative diseases. Thus, avoiding those deficiencies in early life can have large benefits that show up in life later on.
As the latest paper on the triage theory explains,4 “when the dietary availability of a V/M [vitamin/mineral] is moderately inadequate, nature ensures that V/M-dependent functions that are essential from an evolutionary perspective (i.e., required for short-term survival and/or reproduction) are protected at the expense of those that are less essential (i.e., whose lack does not have acute short-term negative consequences but may have long-term insidious effects that increase risk of diseases associated with aging). The triage theory does not imply that any particular V/M deficiency is the only cause of an age-related disease but rather that it is a contributing factor along with the sum of all contributing causal factors.” The authors suggest that, if the triage theory is correct, it would have major implications for public health, since as they note (with references cited), most people are modestly deficient in one or more V/Ms and that includes not only poor countries, but wealthy countries, especially among the less wealthy, the obese and the elderly.
While this theory is very plausible, there is still a need for significant evidence in order to establish its validity. Hence, the authors have previously published a paper on Vitamin K as an example.3 Their latest paper4 has analyzed a huge amount of data from published studies to look at selenoproteins from the perspective of the triage theory. The paper is 21 pages long and includes 295 references.
As the authors explain in their new paper, the triage theory makes three predictions concerning selenoproteins (SPs):
As you can well imagine, to support these hypotheses required the analysis of an immense amount of evidence. We will present a few examples of how the authors assessed the data.
First, it was necessary to determine which selenoproteins (SPs) are “essential” and which ones are “nonessential,” requiring a separate analysis. As the authors explain, they used a model for essentiality in which they looked at mouse KOs (knockouts) for various selenoproteins to determine which ones were either embryonically lethal or where offspring had severely reduced fertility. Those SPs would be “essential” from the perspective of evolution because they would have negative effects on short-term survival and/or negative effects on reproduction. Though the authors recognize that a rodent knockout model is not an ideal or perfect way to identify “essential” uses for vitamins or minerals in humans, it is a reasonable way to begin an inherently complex analysis. In this way, the authors were able to determine, for example, that cytosolic cGpx4 (selenium-containing glutathione peroxidase 4) was essential for embryonic development and another, mitochondrial mGpx4 (selenium-containing glutathione peroxidase 4) was essential for fertility. “The lethality of the cGpx4 KO is consistent with its unique function in protecting against damage from lipid peroxidation and participating in critical lipid peroxide signaling pathways. Severe infertility of mGpx4-KO offspring is also not surprising, given the fact that mGpx4 plays an essential structural role in spermatozoa.”
Distribution of Selenium When Selenium Supply Is Deficient
Prediction 1 proposed that essential SPs would be more resistant than nonessential SPs to selenium deficiency. In other words, when there is only a limited supply of selenium available, it would be expected that the essential selenoproteins would get selenium so as to be able to fulfill their more critical functions before any remaining selenium would be distributed to the nonessential selenoproteins. To determine this, in one example, the authors looked at the relative sensitivities to deficiency of Gpx4 to overall Gpx activity (primarily Gpx1) in rodent models of modest and severe selenium deficiency in liver, kidney, thyroid, muscle, heart, lung, and testis, and (as they report) the essential SP Gpx4 was more resistant to selenium deficiency (either moderate or severe) compared to overall Gpx activity (primarily Gpx1) in all rodent tissues examined. The data for these analyses were obtained from 37 research reports. “… differences between Gpx4 and overall Gpx activity are significant in almost all cases where statistical comparisons were possible (i.e., where >2 experiments were available) … .”
When Selenium Deficiency Results in Decreased Function of Selenoproteins That Protect Against Diseases of Aging
Going on to Predictions 2 and 3, the authors examined the literature to analyze whether decreased functionality of nonessential SPs increase the risk of diseases of aging, and whether there is evidence of a causal relationship. As the authors note, “[i]t is extremely difficult, if not impossible, to test this prediction directly in long-term randomized controlled trials, as we have discussed.” Hence, this analysis used epidemiological studies and other genetic and mechanistic evidence, “to ask whether the same diseases or conditions of aging that are prospectively associated with modest Se [selenium] deficiency are also linked to phenotypes of nonessential SP mouse KOs or human mutants, and whether plausible mechanisms suggest a causal connection between these same SPs and diseases.” The authors point out that there is a large body of evidence that links genetic loss of nonessential SP activities to phenotypes similar to those of diseases or conditions of aging associated with modest Se deficiency, suggesting that causal linkages between dysfunction of nonessential SPs and diseases of aging is possible. As they explain, the intent of these data “is not to imply that relationships are necessarily fully established or that causal linkages have been clearly demonstrated” but to establish that enough evidence exists to provide plausibility to the causal relationship.
The authors also note that mutated versions (SNPs, single nucleotide polymorphisms, of the selenoprotein gene) of essential SPs are also linked to age-related diseases and point out this is not inconsistent with the triage theory, which “predicts only that modest Se deficiency is more likely to impair nonessential SPs than essential SPs.” Moreover, as they also point out, there are many causal factors other than genetic and nutritional ones that may impact the likelihood of disease.
Modest Selenium Deficiency Linked to Increased Risks of Cancer, Cardiovascular Disease, and Infection
The authors conclude that predictions 1, 2, and 3 were largely borne out by the data. They note, for example, that numerous epidemiological studies “suggest that Se deficiency is prospectively linked to increased cancer risk, and various [selenoprotein] mutants in mice and humans, are also linked to increases in cancer risk. Other diseases or conditions prospectively associated with modest Se deficiency that are similar to nonessential SP mutant phenotypes … include increased DNA damage, increased cardiovascular disease and related conditions, reduced resistance to infection (primarily viral), and poor cognitive function.” The authors then go on to analyze a variety of mechanisms that might be involved in the increased risk of these diseases.
In summing up, the authors explain that, “The most obvious value of the theory is that it provides a rationale for why a particular class of V/M [vitamin-mineral]-dependent proteins (i.e., those that are nonessential) may not be fully functional even at modest levels of V/M [vitamin-mineral] deficiency not accompanied by any obvious clinical signs. The value of this insight is that it suggests a strategy for identifying sensitive biomarkers of V/M [vitamin-mineral] deficiency and candidate proteins mechanistically linked to disease. An important limitation of broadly applying the approach followed here is that mouse KOs are not necessarily reliable predictors of essentiality in humans … because of many species differences, some known and some as yet unknown.”
We thank the authors both for creating the triage theory1,2 and for the incredible amount of work done in the examination of the evidentiary basis for the triage theory.3,4 The result is truly a valuable contribution to public health. We hope it gets the attention it deserves.
Uncoupling Protein 1 (Ucp1) Increases Energy Expenditure in Brown Adipose Tissue
Possible Induction of Expression of Ucp1 With EGCG or Curcumin
A recent paper1 reports increased expression of the thermogenesis gene Ucp1 (uncoupling protein 1) that increases energy expenditure in brown fat with a demethylating drug, 5-aza-deoxycytidine. This proof of principle paper suggests that other demethylating agents, such as EGCG (the major green tea catechin) and curcumin (found in turmeric root) may also have this effect. If so, it provides evidence of a potential mechanism to support the use of EGCG and curcumin in weight control regimens.
One of the distinguishing features of brown fat as compared to white fat is that brown fat, but not white fat, contains Ucp1 and when activated (by adrenergic stimulation1B or exposure to cold) burns off fat to generate heat, a process called thermogenesis. The Ucp1 is called an uncoupling protein because the way it works is by disengaging the oxidative phosphorylation that would otherwise take place in mitochondria to produce ATP to the use of that fuel to create heat.1
The authors1 report data in this study that shows that demethylation of the Ucp1 promoter by the drug 5-aza-deoxycytidine results in increased expression of Ucp1. They also report that there is a silencing modification on the Ucp1 enhancer in white fat, while a marker indicating activation appears on the Ucp1 promoter in brown fat in response to a cold environment. The control of whether a gene is turned on or off by methylation in genes or histones is called epigenetics. The silencing feature in the Ucp1 gene in white fat is essential to white fat acting as a “thrifty” store of fuel for when food is scarce.
This discovery is very important because for a long time scientists have been studying how to cause white fat to undergo “browning,” natural processes that stimulate white fat to express some of the properties of brown fat, especially the all-important energy expenditure that helps eliminate excess storage of white fat and its associated negative effects on health. In fact, it has been found possible to produce “browning” of white fat to become more like brown fat.1C,1D But increasing the expression of Ucp1 to increase energy expenditure in brown fat via an epigenetic mechanism is a different way of increasing energy expenditure to help prevent obesity and its associated disorders (e.g., type 2 diabetes). Importantly, this method may be easier at present with the availability of safe-to-use natural products that have been shown to act as demethylating agents.1F,1G
1. Shore et al. Role of Ucp1 enhancer methylation and chromatin remodelling in the control of Ucp1 expression in murine adipose tissue. Diabetologia. 53:1164-73 (2010).
1B. Inokuma et al. Indispensable role of mitochondrial UCP1 for antiobesity effect of beta3-adrenergic stimulation. Am J Physiol Endocrinol Metab. 290:E1014-21 (2006).
1C. Fisher et al. FGF21 regulates PGC-1alpha and browning of white adipose tissues in adaptive thermogenesis. Genes Dev. 26:271-81 (2012).
1D. Mitschke et al. Increased cGMP promotes healthy expansion and browning of white adipose tissue. FASEB J. 27:1621-30 (2013).
1E. Liu et al. Curcumin is a potent DNA hypomethylation agent. Bioorg Med Chem Lett.19:706-9 (2009).
1F. Fang et al. Tea polyphenol (-)-Epigallocatechin-3-gallate inhibits DNA methyltransferase and reactivates methylation-silenced genes in cancer cell lines. Cancer Res. 63:7563-70 (2003).
The short chain fatty acid butyrate (produced by certain microbes in the lower digestive tract from indigestible fermentable fiber that reaches the colon) and the vitamin niacin (nicotinic acid, vitamin B3) both act as ligands for (activating) the GPR109A receptor.1,2This surprising link has resulted in both additional understanding of how niacin works and what butyrate does, but also introduces additional questions concerning how this all adds up, as not that much is known about GPR109A or how niacin works.
A recent paper3 explains that in a mouse model lacking the GPR109A receptor, the anti-lipolytic effect of niacin (inhibition of enzymatic release of free fatty acids) is blocked—but this didn’t have an effect on the usual beneficial changes in plasma LDL and HDL levels produced by high-dose niacin. Thus, niacin’s effects on LDL and HDL are not linked to GPR109A, but its antilipolytic effect is. Meanwhile, the tumor-suppressive effects of butyrate in the colon were found to be mediated by butyrate acting as a ligand at the GPR109A receptor.2 As the authors2 explain, the circulating level of butyrate (about 5 μmol/L) is not high enough to activate the GPR109A receptor, but in the colon, butyrate levels are much higher (about 20 mmol/L) and, at that concentration, able to activate the receptor. Thus, the researchers conclude that, “GPR109A mediates the tumor-suppressive effects of the bacterial fermentation product butyrate in colon.”
Niacin was proposed to reduce the progression of atherosclerosis independently of its lipid-modifying effects through GPR109A mediated antiinflammatory effects in immune cells.1 In one paper,4 human monocytes were pretreated with niacin and then activated by the addition of the Toll-like receptor 4 immune stimulant bacterial lipopolysaccharide. Determination of the resulting secretion of proinflammatory mediators revealed that niacin reduced the secretion of TNF-alpha by 49.2 ± 4.5%, reduced IL-6 by 56.2 ± 2.8%, and reduced monocyte chemoattractant protein 1 by 59.3 ± 5.3%. Interestingly, inhibition of prostaglandin D2 receptor (activation of which causes niacin flushing) did not alter the antiinflammatory effects of niacin described here. This may mean that preventing niacin flushing won’t interfere with niacin’s antiinflammatory effects, but doesn’t tell us whether preventing niacin flushing would interfere with niacin’s effects on HDL and LDL. “The jury is still out” on whether it is a good idea to interfere with niacin flushing. See the June 2009 issue of this newsletter for a speculative article we wrote on the niacin flush.
Colon cancer is reported to be able to silence GPR109A by increasing DNA methylation at that receptor, but the expression of GPR109A can be restored in the presence of butyrate and niacin.2
We wonder about the possibility of an additive antilipolytic effect of butyrate and niacin in the general circulation. Although the concentration of butyrate is much too low (about 4000 times too low in the general circulation) to activate GPR109A by itself, it would be interesting to determine whether it might add anything to the antilipolytic effect of niacin. As powerful anti-inflammatory effects of niacin in monocytes have been identified recently as mediated by GR109A, and as butyrate is a ligand of GPR109A (at least at its concentration in the colon), the combination could be very potent in reducing the risk of colon cancer and inflammatory conditions in the lower digestive tract.4
Conspicuously absent from these data and from the analysis of anti-atherosclerotic mechanisms resulting from fermentation of indigestible fiber reaching the lower digestive tract is the large amounts of hydrogen that can be produced by gut microbes in residence there. Whether the presence of all that hydrogen is additive with or synergistic with the anti-atherosclerotic properties of the short chain fatty acids, if it is, remains to be explained.