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By depleting       ergy savings offered by CFLs, which include  Nutrition and Physical Degeneration,  whose
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             glutathione      reduced mercury emissions from coal-fired  ideas Chris Masterjohn subsequently developed
                              power plants, make them desirable (a debate that  in his research on fat-soluble vitamins; in Sally
                      and     is beyond the scope of this article).    Fallon Morell’s and Thomas Cowan’s Nourish-
           disabling the         Finally, significant sources of local ex-  ing Traditions Book of Baby and Child Care;
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           glutathione-       posure to mercury may include incinerators,  and in the more epigenetically focused Deep
                              coal-fired power plants, crematoria and other  Nutrition by Catherine and Luke Shanahan.
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                  related     industrial processes. For over a decade, the EPA
               enzymes,       has attempted to restrict mercury emissions  MERCURY AS ANTINUTRIENT
                mercury       from U.S. coal plants by about 90 percent, but   Mercury readily binds to sulfhydryl, a type
                              the rule is under litigation, and legal experts  of sulfur also called a thiol. The thiol is the major
             impairs the      predict that enforcement is years away. In some  reactive site within the amino acid, cysteine,

         detoxification       countries, gold mining techniques that employ  which is ubiquitous in biochemically active
                 of many      mercury remain a significant source of exposure  proteins such as enzymes. The human body
                              for miners and local populations. U.S. miners  contains tens of thousands of enzymes, which
               toxicants,     used these techniques during the Gold Rush.  drive most fundamental biological processes.
                ironically                                                 Mercury also binds strongly to selenium,

               including      DEVELOPMENTAL AND                        a cofactor for several dozen enzymes involved
                                                                       in vital tasks such as thyroid function and brain
                              EPIGENETIC TOXICITY
                mercury          The developmental period from conception  antioxidant protection. Although said to protect
                    itself.   through early childhood is a window of vulner-  against mercury toxicity, selenium’s protective
                              ability in which both epigenetic and neurological  scope is limited by its intracellular availabil-
                              damage can occur at exposures far lower than  ity. This is governed by kidney processes that
                              those known to cause toxicity in adults. Epi-  limit the amount of such minerals in the blood-
                              genetics refers to the alteration of gene expres-  stream and by specialized channels within the
                              sion (turning genes on and off)—usually via  cell membrane that control mineral transport
                              environmental factors—without alteration of  from the bloodstream into cells. Lipophilic
                              the DNA nucleotide sequence itself, in a manner  mercury, on the other hand, has no such limits
                              that can be passed to offspring.         when entering cells. Moreover, mercury can
                                 Mercury is a potent epigenetic toxicant of  block selenoprotein P, a substance that stores
                              alarming scope, with both direct and indirect  and transports selenium to cells.  Therefore,
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                              effects on gene expression. Mercury directly  selenium offers only limited protection against
                              targets the cysteine that comprises the DNA-  mercury exposure.
                              binding sites on most gene transcription fac-  The body’s most important intracellular an-
                              tors. In addition, it targets the cysteine in DNA  tioxidant mechanism is the glutathione system.
                              methyltransferase enzymes, which play a role  Glutathione detoxifies mercury by binding it (in
                              (DNA methylation) in normal gene expression.  a process called glutathione conjugation) into a
                              Indirectly, mercury promotes severe oxidative  less toxic form suitable for excretion through the
                              stress. Early-life stressors are known to induce  bile. The glutathione system has been found to
                              changes in gene expression that set the stage  be crucial in the detoxification of thimerosal.
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                              for disease in later life.  Thus, unfortunately,  However, because the glutathione molecule and
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                              exposure to mercury in either parent, even prior  its related enzymes employ cysteine, they also
                              to conception, can affect the child’s own genetic  are targets for mercury. Mercury can damage the
                              expression.                              body’s glutathione system both by depleting the
                                 Epigenetic damage may range from mild  glutathione molecule itself and by blocking the
                              to severe, and the resulting phenotype may  enzymes that synthesize and recycle glutathione
                              include characteristics such as dental defor-  and facilitate its use. By depleting glutathione
                              mities, myopia, asymmetries of the face and  and disabling the glutathione-related enzymes,
                              disproportions of the body. Such characteristics  mercury impairs the detoxification of many
                              are described in Weston A. Price’s pioneering  toxicants, ironically including mercury itself,

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