Wednesday, January 23, 2013

Are starches safe? Part 2


(SEM image of corn-derived granule in blood after a serving of mueseli)

Previously on this blog, it was stated that starches and cereal grains were good food for cows and horses, but not man.  Man is instead better off eating food that is readily, easily, and perfectly digested.  Cases in point: fruit and fruit juices.  I will put forth herein why this is the case, and expand on some of the perils of excess starch consumption discussed in the last post.
                                               
A prominent feature of consuming starches concerns the previously discussed phenomenon called persorption (aka translocation).  Briefly, persorption describes the absorption of non-soluble microparticles through the intestinal lining and thereafter into the lymph vessels, mesenteric veins, and then distributed to tissues throughout the body.

Although persorption was known about since the mid 19th century, the research on it has been sparse. (On my last search for articles on the topic in pubmed and medline, using the search terms “persorption” and “starch granule”, only five results were found.)

Nonetheless, there is still a lot we do know.  For one, we know that starch granules can appear, really, anywhere in the body, including the urine, cerebrospinal fluid, peritoneal fluid, fetal blood, umbilical cord, and milk of lactating mothers. 

Saturday, January 19, 2013

Protective inhibition, energy generation, and the neuroprotective effects of ATP


Terminology

Axon: the slender part of a neuron that conducts electrical impulses away from the neuron’s cell body.
Autonomic ganglia: a cluster of neurons that provides a junction between the autonomic nerves originating from the brain and spinal cord, with those supplying tissues in the body.
Glial cells: non-neuronal cells that provide support to neurons by, for instance, producing myelin.
Heat shock proteins: “chaperone” proteins that, among their many other roles, help us resist stress (including heat stress).
Purine: a heterocyclic aromatic compound, consisting of a pyrimidine ring and an imidazole ring.  Examples include caffeine, adenosine, AMP, ADP, and ATP.
Protective inhibition: an organism’s response to overwhelming stimuli, manifesting as the cessation of metabolic activities.
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Tuesday, January 15, 2013

Saturated fats, unsaturated fats, endotoxin, and implications of the Mani study



Recently, a study by Mani et al., was brought to my attention (Mani, Hollis, & Gabler, 2013).  Although I could only get my hands on the study’s abstract (the full paper is not available yet), in it, similar to the protocol followed by the studies referenced on this blog by Ghanim et al., pigs were fed 5 different oils, each given in porridge: coconut oil, olive oil, vegetable oil, fish oil, and cod liver oil.

Thereafter, blood samples were drawn from each pig at baseline, and at hours 1,2,3, and 5.  Surprisingly, changes in blood endotoxin concentrations were lowest in the pigs who received fish oil, and highest in those who received coconut oil; in fact, as much as 2-fold more, and in every sample analyzed.

As opposed to starch, any increase in blood endotoxin levels seen on the ingestion of fat is not likely due to an increase in bacterial proliferation and metabolic activities in the intestines.  Rather, it is more likely due to an increase in the transport of endotoxin from the intestines and into the body.  This is why results of the Mani study were surprising: For one, long-chain unsaturated fats stimulate chylomicron formation in the intestines, and this is one means by which endotoxin is taken into the body.  And two, unsaturated fats weaken the intestinal barrier, enhancing the incidental passage of substances like endotoxin into the body. 

Sunday, January 6, 2013

Carbon dioxide, Glycation, and the Protective Effects of Fructose




Glycation processes and the potentially protective effects of an intensely active metabolic rate are topics that have been referenced on this blog frequently.  Glycation and cross-linking of molecules in the body contribute to the complications of diabetes and the changes in tissues seen in aging.  A salient consequence of these processes is the stiffening and loss of functioning of tissues in the body—including the skin, where a major substrate for glycation processes exists: collagen. 

Collagen is not only found in the skin, but also in the arteries, cartilage, and bones.  So, the health of the skin (its rigidness, degree of wrinkling, etc.) can serve as a (rough) barometer of the glycation processes that occur in the body. 

With age cross-linked proteins accumulate in tissues throughout the body.  This is a consequence of a few things.  For one, the turnover of proteins is decreased.  Two, the synthesis of proteins, despite the availability of amino acids, is, to some extent, impaired.  Three, fat is oxidized in preference to glucose, and as a result less carbon dioxide is produced and oxidative stress is promoted, thereby creating the conditions for high rates of AGE formation.  And four, energy production is diminished due to the cumulative damages incurred to mitochondrial respiratory protein complexes.

Thursday, January 3, 2013

Stress, adaptation, and diabetes: an integrated picture (ABRIDGED VERSION)


A Canadian physiologist, Han Selye, advanced the research on stress and its physiological effects in the body in a series of studies in rats.   He found that chronic stress, regardless of the source, would produce characteristic changes in the body, and would, if prolonged, enlarge the adrenal cortices, atrophy the lymphatic organs, and ulcerate the lining of the stomach and duodenum (though, we know now that other organs are involved.)

Broadly stated, stress is ever present, so continual demands are placed on the body requiring ongoing adaptation to maintain physical and chemical balance, as well as the integrative functioning of its parts.  When this balance is disturbed, say, when stress is excessive or prolonged, the ability to adapt falters, fails, and, finally, pathology manifests.

In principle, these diseases of stress should be reversible, as long as the metabolic disturbances underlying them are eradicated, and oxygen and nutrients are supplied thereafter.  Thus, the exposure to stressors and disease can be conceived to exist on different points on the same continuum.  With regard to the interest of diseases, stress isn't the issue per se; rather, it is the body's ability to adapt to the stressors that it is continuously being exposed to.