DIGESTIVE ENZYME RESEARCH
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Br J Nutr.
2002 May;87 Suppl
2:S145-51. |
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Gastrointestinal effects of prebiotics.
Cummings JH, Macfarlane GT.
Department of Molecular and Cellular Pathology,
The defining effect of prebiotics
is to stimulate selectively the growth of bifidobacteria
and lactobacilli in the gut and, thereby, increase the body's natural
resistance to invading pathogens. Prebiotic
carbohydrates may also have additional, less specific, benefits because they
are fermented in the large intestine. The prebiotic
carbohydrates that have been evaluated in humans at the present time largely
consist of fructans or galactans.
There is consistent evidence from in vitro and in vivo studies that these are
not digested by normal human enzymes, but are readily fermented by anaerobic
bacteria in the large intestine. There are no reports of faecal
recovery of measurable quantities of prebiotic
carbohydrates. Through fermentation in the large intestine, prebiotic
carbohydrates yield short-chain fatty acids, stimulate the growth of many
bacterial species in addition to the selective effects on lactobacilli and bifidobacteria, they can also produce gas. Along with other
fermented carbohydrates, prebiotics have mild
laxative effects, although this has proved difficult to demonstrate in human
studies because the magnitude of laxation is small.
Potentially, the most important effect of prebiotic
carbohydrates is to strengthen the body's resistance to invading pathogens and,
thereby, prevent episodes of diarrhoea. At the
present time, this effect has not been convincingly demonstrated in either
adults or children, although there have been attempts to ameliorate the diarrhoea associated with antibiotics and travel, but
without success. However, prebiotic carbohydrates
clearly have significant and distinctive physiological effects in the human
large intestine, and on the basis of this it is likely that they will
ultimately be shown to be beneficial to health.
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Am J Physiol
Endocrinol Metab. 2004
Jan;286(1):E64-76. Epub
2003 Sep 9. |
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Branched-chain amino acid catabolism: unique
segregation of pathway enzymes in organ systems and peripheral nerves.
Sweatt AJ, Wood M, Suryawan
A, Wallin R, Willingham MC, Hutson
SM.
Department of Biochemistry,
We have examined the localization of the first two
enzymes in the branched-chain amino acid (BCAA) catabolic pathway: the
branched-chain aminotransferase (BCAT) isozymes (mitochondrial BCATm and
cytosolic BCATc) and the
branched-chain alpha-keto acid dehydrogenase
(BCKD) enzyme complex. Antibodies specific for BCATm
or BCATc were used to immunolocalize
the respective isozymes in cryosections
of rat tissues. BCATm was expressed in secretory epithelia throughout the digestive tract, with
the most intense expression in the stomach. BCATm was
also strongly expressed in secretory cells of the
exocrine pancreas, uterus, and testis, as well as in the transporting
epithelium of convoluted tubules in kidney. In muscle, BCATm
was located in myofibrils. Liver, as predicted, was not immunoreactive
for BCATm. Unexpectedly, BCATc
was localized in elements of the autonomic innervation
of the digestive tract, as well as in axons in the sciatic nerve. The
distributions of BCATc and BCATm
did not overlap. BCATm-expressing cells also
expressed the second enzyme of the BCAA catabolic pathway, BCKD. In selected
monkey and human tissues examined by immunoblot
and/or immunohistochemistry, BCATm
and BCATc were distributed in patterns very similar
to those found in the rat. The results show that BCATm
is in a position to regulate BCAA availability as protein precursors and
anabolic signals in secretory portions of the
digestive and other organ systems. The unique expression of BCATc
in neurons of the peripheral nervous system, without coexpression
of BCKD, raises new questions about the physiological function of this BCAT isozyme.
Enzyme Research
Research found thirty
times more enzymes in the saliva of young adults than in that of persons sixty-nine years of age.
Howell, E. Enzyme Nutrition.
Avery Publishing Co. 1985
Researchers have also
found higher levels of amylase in the urine of young adults as compared to
older adults.
Ivy, A., Schmidt, C., Beazell, J..
Journal of Nutrition.
12:59-83. 1936
Bartos and Groh enlisted ten young men
and ten older men for a study in which they used a drug to stimulate the
pancreatic juice flow. The juice was then pumped out and tested. The
researchers discovered that considerably less of the enzyme amylase was present
in the pancreatic juices of the older men.
Bartos and
Groh. Proceedings of the Society
for Experimental Biology and Medicine 37:613-615.
Other research indicates
that not only are there fewer enzymes in the pancreas. But
also in the trillions of cells in our bodies as we age.
Ivy, A., Schmidt, C., Beazell, J..
Journal of Nutrition.
12:59-83. 1936
Research on rats given
supplemental enzymes showed that the supplemented rats had more enzymes than
the control group of rats, clearly indicating the existence of a fixed enzyme
potential. The enzyme-fed rats lived three years in comparison to two years for
those rats fed an enzyme-free diet.
Howell, Edward. Food
Enzymes for Health and Longevity. Lotus
Press, 1994.
Research done on rats and
chickens that were fed cooked foods revealed that the pancreas gland enlarged
to handle the extra burden of the enzyme-deficient diet. Hence, the animals got
sick and failed to grow. The pancreas is responsible for making and secreting
many digestive enzymes. Our pancreas will enlarge when called upon to process
more enzymes or digest cooked food. Ruminant animals such as cattle, goats,
deer and sheep get along with pancreas about a third as large as ours because
of their raw food diet. However, when these animals are fed heat-processed,
enzyme-free food, their pancreas enlarged up to three times the normal size
than when fed on a raw plant diet.
Grossman, M. Greengard, H, Ivy, A. American Journal of Physiology.
141:38-41, 1944
The following information is excerpted from a Transformation Enzyme Corporation white paper titled "Oral Enzymes: Facts and Concepts" by Dr. Mahamane Mamadou, Ph.D.
Effect of Oral
Enzymes on the Immune System
Another molecule that directly impacts in the modulation of the immune system
is alpha 2-macro-globulin. High concentrations of free alpha 2-macroglobulin in
the blood hinders the activity of the immune system (Hubbard et al., 1987).
However, when oral enzymes are taken and absorbed into the blood stream, they
bind to the alpha 2-Macroglobulin, and thus reduce the concentrations of free
alpha 2-macroglobulin. This reduction of alpha 2-macroglobulin has been shown
to boost the immune system. Oral proteases and amylases have also been reported
to modulate the secretion of cytokines (Desser et
al., 1993). Cytokines are important immune messenger molecules that control the
effectors immune cells. Additionally, oral enzymes help modulate and control
cell adhesion molecules, receptors and other messenger molecules that tend to
inhibit the immune system and/or provide anchor to metastatic
cancer cells (Targoni et al., 1999).
Effect of Oral
Enzymes on Other Human Health Conditions
The application of enzymes in clinical studies has
encompassed various disease conditions, and the results have proven to be
better therapeutic agents or at least equally effective as other conventional
forms of treatments.
However, as enzymes have been shown to have fewer to absent side effects, their use may be a safer alternative. Some of the conditions where clinical enzyme studies were conducted include:
This is just a brief list of areas where enzymes have been implicated as treatment agents. There are several other physiological, biochemical disorders as well as infectious diseases where enzymes have been proven to provide therapeutic benefits. The different roles of oral proteases are being continuously investigated in relation to various diseases and cancers, such as breast cancer, prostate cancer, AIDS, and other immune system disorders.
As indicated by the clinical data cited, the use of hydrolytic enzymes as therapeutic agents has been proven effective in many areas. Enzymes could be used alone or in combination with other medicinal agents to prevent and alleviate health disorders. Oral proteases perform most of their action as active adjuvants to "biological response modifiers" (BRM).