Introduction
Bone is an important component of our body architecture. It serves several functions ranging from the support, protection, production etc. Bone must always be in the right state for the body to be stable simply because of those functions. Ageing is one major component that usually affects bone in terms of the strength however, there are several other disorders that tend to affects bones without the input of aging. Those disorders come into play by affecting either the structural component or chemical makeup of the bone. The resultant effects are the affectation of the function of the bone.
Osteoporosis is one major bone disorder that is somewhat common. The name almost simply describes what the disorder is about. It is all about a porous situation of the bone. The implication of this is that there is a reduction in the bone mass or density. This simply means that the bone is losing the density hence becoming weak to carry out the basic functions. The microscopic structure that appears like an
In this disorder, there is a progressive change that results in decrease in bone mass and density, deterioration of the bone microarchitecture and protein content. This increases the risk of bone fracture and falling. There are basically two major types: the primary and secondary types. The primary is that which is seen mostly in postmenopausal women although also seen sometimes in men. The ratio of occurrence of this type for women to men is 2:1. The secondary type is usually seen in both sexes at equal ratio. The secondary type usually occurs at any age. About 52 million Americans are reported to have osteoporosis and low bone mass which could place individual at increased risk of osteoporosis (NOF, 2013).
Discussion
Bone physiology
It is important to understand the bone remodeling physiology so as to understand how osteoporosis occurs. There are three basic types of cells that are usually involved in the remodeling stages. These are the osteoblast (bone forming cell), osteoclast (bone degrading cell) and osteocyte (an osteoblast-derived post mitotic cell serving as a mechanosensor and an endocrine cell). The other components are the collagen and noncollagenous proteins tagged osteoid. The bone growth is both longitudinal and radial growth, reshaping and remodeling. Bone formation which is called the ossification comes in two ways. Intramembranous ossification and endochondral ossification.
Bone remodeling is a bone process that occurs over several weeks involving two major bone cells which are the osteoblast and osteoclast. These cells are arranged within temporary anatomical structures tagged "basic multicellular units" (Raggatt & Partridge, 2010). The process is divided into the Activation, Resorption, Reversal, Formation and Termination phases. The activation phase is characterized by the endocrine bone remodeling signal Parathyroid hormone binding to its receptor on preosteoblasts. There is also osteocyte apoptosis at this phase with associated inhibition of osteoclastogenesis.
The next phase which is the resorption phase is characterized by release of MCP-1 from osteoblast, recruitment of preosteoblast towards the bone surface, decrease in the osteoblast expression, increase in CSF-1 and RANKL production with subsequent promotion proliferation of osteoclast precursor (Raggatt & Partridge, 2010). During the reversal phase, there is engulfment cells and removal of demineralized undigested collagen away from bone surface. Transition signals are also generated at this phase. Formation phase is characterized by formation of signals and molecules from the degraded bone matrix, and mature osteoclasts. The termination phase is the last phase. It occurs when the amount of bone resorbed has been adequately replaced; the remodeling cycling can then conclude (Raggatt & Partridge, 2010).
Calcium in the body has a strong dependence on the bone. This is because 99 percent of the body's calcium is majorly found within the bone hence bone plays an important role in calcium metabolism. When there is a need for the buffer system for the blood calcium level, bone can help play an important buffer system role hence helping to maintain the constant level of the freely moving calcium which are always needed by different body soft tissues, extracellular fluid and blood. The pool that maintain the free calcium is maintained partly by calcium resorption while bone formation help control the excess state of such type of calcium.
Parathyroid hormone helps regulates serum calcium via various mechanism. Those mechanisms are majorly by acting on the bone, kidney and intestine. The major function on the bone is that which relates to the enhancement of release of calcium from the storage that is within the bone. This action is an indirect action hence causing osteoclastic activities which lead to bone resorption. It is this bone resorption that contributes to the increase the level of serum calcium since the bone destruction will cause calcium to flow more into the blood. At this same process of causing the indirect bone resorption, the PTH also initiate a form of lock on the osteoblast which will keep the bone forming process from forming.
Risk Factors
The risk factors depend majorly on the sex and nutrition. Being a female is a risk factor and poor consumption of nutritional calcium predisposes the individual to low level of calcium. As far as calcium is the basis for the etiology of osteoporosis, low nutritional calcium will predispose the individual to poor serum calcium which is a risk factor for osteoporosis. This is because bone store will be depleted. Some of the foods that can help the individual maintain the normal calcium levels are the low fat milk, yogurt, cheese, Chinese cabbage, soy products, okra, broccoli and almonds.
The genetic code understanding found by the scientist help to understand that there are reasons why some osteoblast and osteoclast are more active than the other. These were noted to have some form of risk predisposition to having osteoporosis. The genetic factor has also been found to contribute to osteoporosis from the perspective of some individual have bone size and quality that do not favor a good bone structure but support more of osteoporosis predisposition.
Signs and symptoms
There are usually no warning signs relating to the osteoporosis but an individual that has experience some form of fractures with minor falls especially fractures at the wrist and hip or spinal bone fractures can be at a high risk of having osteoporosis.
Exercise that help osteoporosis patients are the flexibility forms of exercises. Steroids are type of organic compound that are made to contain cycloalkane rings. They have different functions such as anabolic in nature. Peak bone mass is the amount of bony tissue present at the peak of the maturation of the individual.
Conclusions
Both of them should live a healthy lifestyle such involving regular exercise, healthy eating and quitting any form of smoking or alcohol.
Reference
Raggatt, J.L. & Partridge, N.C. (2010). Cellular and Molecular Mechanisms of Bone Remodeling. Signal Transduction. Cell Biology.
Retrieved 10, November, 2013 from http://www.jbc.org/content/285/33/25103.full
Crockett et al, (2011). Bone remodelling at a glance. Cell science at a glance. Journal of cell science.
Retrieved 10 November, 2013 from http://jcs.biologists.org/content/124/7/991.full
NOF, (2013). What is Osteoporosis?
Retrieved 09 November, 2013 from http://nof.org/articles/7
International Osteoporosis Foundation (2013). Pathophysiology: Biological causes of osteoporosis.
Retrieved 10 November, 2013 from http://www.iofbonehealth.org/pathophysiology-biological-causes-osteoporosis
