Teaching the Mechanisms of Type 2 Diabetes Mellitus to
College Anatomy/Physiology Students
Kevin
E. Yocum
New
York Chiropractic College
Abstract
According to the Center for Disease
Control (CDC), the number of individuals diagnosed with disorders involving the
malfunction of glucose transport mechanisms has been steadily increasing over
the last thirty years (Center for Disease Control 2011). Malfunction of glucose
transport mechanisms involves common diseases such as type 2 diabetes mellitus
(T2DM), obesity, and metabolic syndrome. In order for a leveling off or a
decline of the numbers to occur over the next thirty years, a collective
understanding by our healthcare students of how to prevent or minimize disturbances
of these important mechanisms is necessary. This analysis will provide creative
ideas about introducing college-level A/P students to the various mechanisms
involved during consumption and transport of glucose and the pathogenesis of
type 2 diabetes mellitus.
Keywords: glucose, glucose transport,
diabetes, obesity, metabolic syndrome, insulin, type 2 diabetes mellitus, VARK
Teaching the Mechanisms of Type 2 Diabetes Mellitus to
College Anatomy/Physiology Students
Basic human
survival is dependent on the ability of our cells to produce energy. The recipe
for producing energy includes a simple ingredient called glucose. Glucose is a
monosaccharide sugar that is obtained by consuming carbohydrates. Certain
organs and tissues are also able to store and re-manufacture glucose in the
body. Due to the constant need for and the availability of sugars, providing
the body’s cells with glucose would seem to be a simple process that occurs
quite naturally. For many Americans, this simple process has become complicated
by sedentary lifestyle and consumption confusion. Metabolic disorders,
including type 2 diabetes mellitus (T2DM) and obesity have risen dramatically
in the United States over the past thirty years and there do not appear to be
any signs of reversal to this disturbing trend in the years ahead (Center for
Disease Control 2011). In order to begin the process of attempting to reverse
this trend, it is essential that a more widespread understanding of how glucose
is attained, transported, and metabolized is considered.
Many college
students that are taking anatomy/physiology (A/P) have intentions of working in
the healthcare field and some will eventually be caring for patients with T2DM.
Providing students with a clear picture of T2DM will enable them to educate
their patients. This discussion focuses on techniques for teaching glucose
transport and the pathogenesis of T2DM to college A/P students, with specific
attention to the VARK learning styles, a student-centered classroom structure,
and social learning theory.
Glucose
homeostasis is one of the most important negative feedback regulatory functions
of the body. (Kumar et al., 2010) If there is not enough glucose in the blood
for cellular energy and respiration, the cell will starve, leading to tissue
and ultimately organ death. If there is too much glucose in the blood over long
periods of time, the brain and kidneys will suffer severe damage. The
pancreatic hormones insulin and glucagon assist with regulating blood-glucose
levels. When blood-glucose levels rise, the pancreatic beta cells release
insulin into the blood stream. Insulin coats glucose molecules, allowing for
facilitated diffusion of the glucose into cells. When blood-glucose levels are
too low, pancreatic alpha cells release glucagon, which stimulates liver and
skeletal muscle glycogen conversion to glucose. When blood-glucose levels are
problematic to control, many physiological disorders can occur. The most common
group of metabolic disorders involving glucose transport mechanisms is known as
diabetes mellitus (DM). Discussing these concepts requires attention to each
student’s unique learning style.
Using the VARK
scale, the visual learners will benefit from seeing a short video that shows
how insulin attaches to glucose and facilitates the diffusion into the cell.
There is a two minute YouTube video (http://www.youtube.com/watch?v=QeT1V8RmIbU)
that shows glucose transport and digestion in a visually appealing way. The
audio learners will also benefit from watching this short video, as the
lecturer provides a simple and clear explanation to go with the video.
Additionally, both the audio and read/write learners will be listening and
taking notes on the content Powerpoint presentation that I have created, which
includes checkpoint questions. The kinesthetic learners will also appreciate
the YouTube video, as it displays fundamental molecular movement within organs
and tissues that they will be dissecting in the lab. The lab environment is
typically where the kinesthetic learners thrive. The lab portion of
understanding glucose transport and T2DM will be discussed later.
The signs and
symptoms of diabetes mellitus are easily detectable. Sugar has diuretic
properties, so increased blood-glucose levels usually lead to frequent
urination. Due to excess sugar in the interstitial space, osmosis will often
lead to extra fluid movement from the cells into the interstitial space. This
edema leads to more work for the kidneys, including more urine output, or
polyuria. Polyuria leads to excessive thirst. An increase in appetite and
hunger usually goes with DM due to the need for energy from protein and fat. If
cells are unable to receive optimal amounts of glucose to produce energy, the
overall fatigue level of the individual will dramatically increase as well (Werner
2005).
Accurately
diagnosing diabetes mellitus involves the help of a physician. After a patient
intake and vitals examination are done, if the physician suspects metabolic
problems, a urinalysis and a series of blood tests will be ordered. A
urinalysis test strip will show if there are glucose levels in the urine. Dr.
Jayendra Shah, MD found that a diabetics’ perception of tasting sweets is
deficient, so he devised a test involving seven different glasses of water
mixed with varying amounts of sugar. All glasses contained eight ounces of
water and 0, .25, .5, 1.0, 1.5, 2.0, and 3.0 teaspoons of sugar. The glasses
were put into a random order and the patients were asked to take a drink from
each glass, with a rinse between each drink, and rate the sweetness. Non-DM
patients recognized the sweet taste with one or less teaspoons of sugar in
eight ounces of water, while DM patients only recognized the sweet taste at one
and a half to two teaspoons of sugar in eight ounces of water (Shah 1994).
The lab portion
for understanding glucose transport and T2DM includes performing a glucose
urinalysis of the student’s lab partner, the Shah sugar taste test, and a cat
or fetal pig dissection of the stomach, pancreas, liver/gall bladder, and
duodenum region. The social learning within the lab setting is essential for
our healthcare students. In addition to learning the A/P aspects of this
exercise, they also get to play the role of nurse or medical assistant by
collecting and analyzing their partner’s urine and assisting their partner with
performing the Shah sugar test. Visual learners appreciate being able to see
the urinalysis results, while also seeing how complex the pyloric/duodenal
digestive region is. The audio learners will benefit from playing the part of
clinician and practicing active listening with their lab partner. Communication
is extremely important while performing lab tests and the audio learners enjoy
listening to their peers discuss their findings and interpret their results.
The read/write students will find that interpreting the urinalysis dipstick and
checking off their lab list for the dissection is the most beneficial, while
answering the pre- and post-lab questions and writing the lab report also are
appealing. The entire lab exercise is very appealing to the kinesthetic group.
They get to walk to the restroom, clinical role-play, drink a variety of
sugar-water mixes, and dissect part of the GI tract of a cat or fetal pig.
Treatment of diabetes
mellitus generally addresses the need for increased insulin production by the
beta cells of the pancreas, while increasing the affinity of the target cells
for insulin. A decrease in glucose release from the liver and decreasing
carbohydrate absorption rate in the small intestines are also addressed during
the treatment of DM. Treatment for T2DM
includes consumption or diet changes, movement or exercise routines, and oral
medication. Over one-third of T2DM patients are treated with insulin supplementation.
Lifestyle education, stress management, and consumption awareness are typically
part of the treatment protocol as well.
If T2DM is not prevented, recognizing the signs and symptoms early is
essential. Recognition of the signs and symptoms of T2DM may lead to lifestyle
awareness and positive alterations in lifestyle that are consistently
maintained could result in less reliance on medication. In 2007, the direct and
indirect costs of treating DM totaled 174 billion dollars (Center for Disease
Control 2011). A DM patient costs twice as much to treat as a patient who does
not have DM. DM individuals are more susceptible to heart disease,
hypertension, strokes, blindness, amputations, and bacterial and viral
infections and many DM patients will eventually need frequent hemodialysis. Due
to a greater susceptibility to these pathologies, lifespan is greatly decreased
for people who have been diagnosed with diabetes mellitus. I would also include
a link to the website www.choosemyplate.gov
and require each student to complete a one week consumption and movement
journal, beginning on the day of their lab. They would bring their journal to
the following week’s lab and I would show them how to log their consumption and
movement data into the website template. They would have another week to
compose a three page analysis of their consumption and movement based on the
Choosemyplate results. Within their analysis they would be required to discuss
whether, based on their results, they are at risk for T2DM now or in the future
and how they would implement Choosemyplate into a clinical setting.
Metabolic disorders, particularly
type 2 diabetes mellitus, are nearing epidemic proportions in the United
States. With affordable pricing and readily available quick food sources
continuing to rise, expectations for a decline in metabolic disorders would
appear to be bleak. Public understanding of the mechanisms controlling glucose
transport may lead to increased preventative action against metabolic
disorders. A greater awareness can begin in the college anatomy/physiology
classroom, as many A/P students will be affecting the lives of their patients
every day once they enter the workforce. It is essential that they are exposed
to a variety of techniques for understanding the pathogenesis of type 2
diabetes mellitus.
References
Center for Disease Control (2011). National diabetes fact sheet, 2011.
Retrieved from
http://www.cdc.gov/diabetes/pubs/pdf/ndfs_2011.pdf.
Krishnapuram, R. &
Kirk-Ballard, H.(2012). Insulin receptor-independent upregulation
of
cellular glucose uptake. International
Journal of Obesity, 7. doi: 10.1038/ijo.2012.6.
Kumar, Vinay, Abbas, Abdul, Fausto,
Nelson, & Aster, Jon (2010). Robbins
and Cotran
Pathologic Basis of Disease, Eighth
Ed. Philadelphia, Pa: Saunders and Elsevier.
Martini, Frederic, Nath, Judi,
& Bartholomew, Edwin (2012). Fundamentals
of Anatomy
and Physiology, Ninth Ed. San
Francisco, CA: Pearson Higher Education, Inc.
Shah, Jayendra (1994). Kitchen test detects taste defect.
Retrieved from
http://www.thefreelibrary.com/Kitchen+test+detects+taste+defect.-a015911375.
Werner, Ruth (2005). A Massage Therapist’s Guide to Pathology,
Third Ed. Baltimore,
MD:
Lippincott, Williams, and Wilkins.
