The Strength of Our Organs

Organs Don't Fall Apart.

Have you wondered why the organs in your body don't fall apart? What is it that maintains the cells of an organ together, and the nerves and the blood vessels it contains? It is a binding substance (named the collagenous matrix) that forms a supporting network between the cells, the nerves and the blood vessels.

All organs contain such a binding substance holding the cells, the nerves and the blood vessels of an organ together.

Bones are no exception.

The Binding Substance of Organs

What is the binding substance of an organ made of?

It is made of identical molecules assembled in long sequences. Sound familiar? Yes, Plastics! Plastics are made of identical molecules assembled in long sequences.

Plastic material is no innovation. Nature was making similar substances long before plastic were " invented" by mankind. Like plastic, the binding substance of organs is made of repetitive sequences of identical molecules named Proteoglycans.

Proteoglycans are made of proteins and sugars. Sugars are not only fuel for our cells. Various forms of sugar (galactose, xylose, glucosamine, galactosamine) participate in the building of organs.

See newsletter8 for more information on the various forms and functions of sugars (better named "Saccharides")

The Binding Substance of Bones

Bones are no exception. Bones also have a binding substance. However, there is a big difference between the binding substance of bones and the binding substance of other organs. The difference is that in bones the binding substance contains minerals.

Two Function of Bones

It is the mineral content of the binding substance in bones that gives bones their two functions: a structural function to support the body weight against gravity and a less recognized function as storage facility for minerals (and not only calcium).

The human skeleton functions in two capacities: the storage of minerals and structural support of the body. It is the only tissue that behaves as both a major source and a sink of calcium (Ca) and phosphorus (P). Healthy bone is a composite of a collagenous matrix embedded with crystals of hydroxyapatite. On the surface of bone and within the calcified matrix are specialized cells that build and maintain the tissue, and facilitate the movement of Ca and P into and out of serum. Bone undergoes remodeling in response to either damage from mechanical strain or as part of the normal cycle of bone renewal. The process involves distinct steps of cellular activation, bone resorption, and subsequent bone formation. It is a relatively slow process that takes several months, and at any one time occurs at many different sites along the bone surface.

(Hercz G. Regulation of bone remodeling: impact of novel therapies. Semin Dial, 2001 Jan-Feb, 14(1): 55-60.)

The second function of bones, the storage of minerals explains how the calcium density of bones may fluctuate over time. Indeed, the storage of calcium (and other minerals) comprises entry and exit. In bone calcium flows constantly in and out. Calcium flows out of bones at the request of the regulatory system that maintains the calcium content of circulating blood within very narrow boundaries. A crumbling blood calcium level is rapidly life threatening.
Compensation occurs by mobilization of bone calcium. Bone calcium refilling occurs slower than depletion. Nature is organized as to eventually accept brittle bones as a consequence of a life saving process; the preservation of a sufficient calcium level in circulating blood. One can survive with brittle bones, while lack of calcium in circulation kills.

Bone Health Maintenance

What to do to maintain the health of your bones?

Like all molecules in our body, the molecules of the binding substance of our organs, inclusive the molecules of the binding substance of our bones, are the objects of a constant turnover. Molecules of the binding substance are continuously broken down, removed and replaced by new molecules.

The constant shift of molecules implies that we have to provide our organs with a continue supply of building block for the maintenance of the binding substance. Any shortage of supply shall reflect in organ strength, volume and durability. Which is to say that in bone all the molecules that form the bone collagenous matrix, and not only the calcium that impregnates it, are constantly broken down and replaced. Without a sufficient supply of essential building blocks, the restoration of the matrix is incomplete. Hence, less substance is built to store calcium. Any matrix building block deficiency contributes to brittle bones.

Building Blocks

The building blocks of bones are chondroitine, glucosamine, essential fatty acids, at least five vitamins, and beyond calcium, a large variety of other minerals.

Chondroitin and Glucosamine

Chondroitin is a proteoglycan containing the amino acid L-serine and the sugars glucuronic acid, galactose, xylose, glucosamine, galactosamine. (An amino acid is a part of a protein)

Glucosamine and galactosamine are a combination of sugars (glucose and galactose) with the amino acid glutamine.

Although older publications about glucosamine and chondroitin sulfate address solely their use in arthritis , there is more to say about glucosamine and chondroitin sulfate. Recent scientific evidence indicates their essential role in the treatment of osteoporosis.

Essential Fatty acids

Fatty acids are part of fat molecules . Each fat molecule is made of three fatty acids attached to a three carbon carbohydrate (the triose glycerol). The large variety of fat comes from the diversity of fatty acids they contain. Our biochemistry makes fatty acids (and fat) from the sugars (saccharides) of our food. Our biochemistry can make and modify a large variety of fatty acids, except two. The two fatty acids our biochemistry can not synthesize although it can modify them are termed Essential Fatty Acids (EFAs). They are Linoleic acid (LA) and alpha-Linolenic acid (ALA). We have to find LA and ALA in our food or in food supplements.

The role of EFAs in bone health is that they help maintain the calcium supply by :
- increasing the calcium absorption from the gut
- reducing urinary excretion of calcium
- increasing calcium deposition in bone
- improving bone strength by enhancement of the synthesis of the bone matrix

Vitamins

The vitamins with a documented effect on bone health are the vitamin B1, C, D, K, and Folic acid

Vitamin B1
Hemocystein (Hcy) is a molecule occurring naturally in our body. Hcy is what remains from the utilization of methionine (an essential amino acid) found in food. Hcy is further used or discarded. Abnormal accumulation of Hcy has a detrimental effect. The detrimental effects of Hcy are attributed to its spontaneous chemical reaction with many biologically important molecules, primarily proteins. The formation of these Hcy-adducts is dependent on time and on the Hcy concentration.
The formation of these Hcy-adducts leads to loss or diminution of function of the derivative molecules. Irreversible homocysteinylation of long-lived proteins should lead to cumulative damage and progressive clinical manifestations. The bone matrix components are specially susceptible to Hcy degradation

The control of Hcy levels for prevention of bone matrix degradation can be accomplished through vitamin B1 supplementation.

Vitamin C
Vitamin C is considered an essential cofactor of bone matrix formation and large studies report a positive association between vitamin C intake and bone density.

Vitamin D
Vitamin D (vit D) is a rather curious vitamin. It should not be classified as a vitamin. It should be called a hormone. Indeed we make vit D as well as we make all our hormones, while we can not make vitamins. We make vit D from cholesterol, as we make sex hormones and adrenal hormones from cholesterol. We make vit D from cholesterol in our skin with the participation of ultra violet sun rays. Sunlight-deprived people may become vitamin D-deficient (Another curious aspect of vit D is that its production closely parallels the photosynthesis occurring in plants, where sunlight also is used to synthesize molecules)
Vitamin D added to a calcium supplementation has been shown to be particularly efficient in elderly patients, mainly to prevent non-vertebral fractures.
The RDA for vit D has recently been upgraded to 400 IU per day.

Vitamin K
Vitamin K (vit K) is recognized as essential for blood coagulation. What is less known is that calcium supplementation combined with vit K (and with vit D) increases the bone mineral density of the lumbar spine better that calcium alone.

Folic Acid
Folic acid contributes with vitamin B1 to lower the homocysteine level. (See vitamin B above)

Minerals

About sixty minerals occur in bone. Although the function of all of them is not yet well documented, their presence suggests that they may have a (to be defined) role in bone matrix maintenance and bone health.

The minerals with a well-documented effect on bone health are: Calcium, Magnesium, Manganese, Boron, Zinc, Strontium, Iron and Sulfur.

Calcium
Calcium in bone is found under the complex form of calcium hydroxyapatite (CHA).
Calcium supplementation under the form of calcium CHA is more efficient to reduce bone loss in women with osteoporosis than calcium under the form of carbonate, because the absorption of calcium from calcium hydroxyapatite is significantly higher than the absorption of calcium from calcium carbonate.

Phosphorus
The calcium hydroxyapatite crystals of bone also contain phosphorus. Calcium supplementation is recommended for bone maintenance, the same can not be said for phosphorus.
Although phosphorus is an essential nutrient, there is concern that excessive amounts may be detrimental to bone . The reason is that phosphorus intake depletes blood calcium, which triggers parathyroid hormone release that takes calcium from bone to replenish blood calcium. (More :The forgotten Phosphorus and Sugar Story)

Magnesium
Magnesium has an ambivalent role in bone health. Some magnesium is essential for calcium deposit. However, since magnesium stimulates the function of the osteoclasts, too much of magnesium is detrimental to bones. (Osteoclasts are the cell specialized in calcium removal from bone. Their role is important for the maintenance of the calcium level in blood. Excessive osteoclast activity contributes to osteoporosis)
The addition of magnesium in amounts equal to the calcium content in a package to fortify bone is not warranted.

Manganese
Many enzymes contribute to a healthy bone matrix turnover. A great variety of minerals are essential to the enzymatic systems involved in bone matrix maintenance . Manganese is one of them, and bone abnormalities are associated with manganese deficiency.

Boron
Boron favors calcium deposit in bone.

Fluoride
Fluoride incorporation in bone increases the size of the calcium hydroxyapatite crystals, which decreases their solubility.

Zinc
Calcitonin is a hormone produced by the thyroid gland. Calcitonin is essential for calcium deposit in bones . Zinc regulates the secretion of calcitonin from the thyroid gland.

Strontium
Osteoblasts are specialized bone cells that add calcium to the bone structure, Strontium activates the function of the osteoblasts and decreases the number of osteoclasts, thus reducing bone resorption and enhancing bone formation.
Strontium has shown positive effects on bone mass in various animal models of osteoporosis.

Iron
Like manganese, iron is a cofactor for enzymes involved in collagen synthesis.

Sulfur
The strength of the proteoglycans (see above) forming the matrix of bones relies entirely on the numerous sulfur bonds found in proteoglycans.

Digestive Enzymes

Since the health of our bones is closely associated with a constant supply of building blocks and that we have to find the building blocks in our food, it is obvious that any degree of intestinal malabsorption will compromise bone density.

Other Factors

Another aspect of bone health maintenance is that life habits and your hormonal condition also influence the metabolism of your bones.

Life Habits

Diet
Eating seafood favors bone density. Seafood contains highly absorbable calcium.

Physical Activity
Exercise, sport and physical work have in common body movements that increase the local pull of gravity. The pull of gravity stimulates the deposit of minerals in bones.

Hormones

Several hormones influence bone density. (More to come)
The hormones most involved are: Growth Hormone, Dehydroepiandrosterone, Androgens, Estrogens, Parathormone, Thyroid hormone, Progesterone, Melatonin, and Calcitonin.