Thursday, February 5, 2009 . 10:41 PM
Have you ever wondered why do women outlive men and have a more aggressive immune system than males; this is probably the reason for the greater occurrence of Systemic Lupus Erythematosus (SLE) in females.
In our blog, we will be telling all of you out there more about these medical conditions:
a. SLE and its implications for health.
b. Causation of autoimmune type I diabetes mellitus.
So do stay tune to find out more ! =D
a. SLE and its implications for health.
No , seriously , SLE is a highway in Singapore ... hahaha !!!Okay, just kidding..
Well, Systemic Lupus Erythematosus in short is known as SLE or Lupus. SLE is a chronic lifelong autoimmune disease that cannot be cured. It is a condition where the immune system becomes dysfunctional.
Instead of protecting the body like fighting against the foreign bodies such as bacterial, it attacks the healthy tissues and organs in the body causing inflammation.
There are three main types of lupus : Discoidl lupus, Systemic Lupus Erythematosus (SLE) and Drug-Induced Lupus.
Lupus can act on different sites of the body. When skin is the only site which lupus is acting on, it is call as Discoid Lupus.
However, when internal organs such as kidneys, liver, heart is involved, it is identify as SLE. It is seen more in women than man and can be diagnosed even in children. Women from the age 15 to 44 are more susceptible to this disease.
The causes of this disease are still unknown. However, some scientists believe that it correlate to hormones when a woman is pregnant.
Some recently researchers also found that the dysfunction of a key enzyme contribute to SLE. The enzyme called DNase. Although SLE is not contagious, it can be fatal when uncontrolled or triggered severely.While this may be true, SLE can still be controlled though medical drugs like Prednisolone, a steroid to reduce the occurrence of inflammation and commonly used to control SLE.
According to Lupus Association Singapore, almost all patients have shown a decline in the attacks of the disease in the body of these infected patients.
Implications of SLE on health are serious internal organ inflammation such as inflammation of muscles, blood vessels, kidney and even brain. When these vital organs are attacked, they may become damage by SLE. Inflammation in nervous systems, blood vessels and joints will cause pain and swelling in the different parts of the body.
Common symptoms found in patients are fever: no appetite, muscle pain, arthritis, ulcers of mouth and nose, butterfly rash over the cheeks across the nose, scare of sunlight and edema. The most noticeable symptom is the butterfly rash on the face of the SLE patients.
Furthermore, under sun exposure, the condition of the patient may worsen. Some spots like rashes can also be seen around the fingers and toes when the small vessels of the skin are inflamed. The patient may experience hair loss, lungs, inflammation of abdominal organs, arthritis when the condition is not stabilised by medical drugs.
The membrane lining of the heart, lungs and abdominal organs are inflammed and sharp pain will be felt when the person with SLE breathe in deeply.
The inflammation of brain tissues obstructs normal brain function, causing fits, coma or weakness on one part of the body.The blood vessels in kidney are inflammed and will be damaged causing Lupus Nephritis.
Proteins leaks into the urine causing foamy urine and this may leads to fluid retention with weight gain and swelling.(Edema)The swelling worsens as one walks about during the day.
The blood system, the auto antibodies in blood are high, Red Blood Cells are then destroyed (Haemolytic Anaemia) .White Blood Cells are also low and the result is that the body cannot fight viruses. (Leucopenia)Low platelet count (Thrombocytopenia) will occur as well as the antibodies goes against these cells.
Treatments given for this illness are medical drugs like Corticosteroids, Antimalarial drugs, Aspirin and Other Anti-Inflammatory drugs, Immunosuppressive drugs and Ointments/Skin creams. They are used to prevent inflammation, controlling skin problems and protection from sun.
Alright, as we all know, picture speaks more than a thousand words so...
let the pictures do the talking instead! :
* WARNING:THE FOLLOWING PICTURES MAY CAUSE SOME DISCOMFORT SO.....
IF YOU CANNOT TAKE IT, JUST SKIP THIS SECTION! =p
These picture illustrates the butterfly rashes seen in SLE patients.
And just in case you belong to those visual learners who learn better through animations like videos, we have included for you the following video link to tell you more about SLE! So sit back, rrelax and enjoy your learning journing into the SLE world! =D
: http://sg.video.search.yahoo.com/video/play?p=Systemic+Lupus+Erythematosus&ei=UTF-8&js=1&fr=yfp-t-web&fr2=tab-img&tnr=21&vid=000152654072
Part b: Causation of autoimmune type I diabetes mellitus
- A BRIEF INTRODUCTION INTO TYPE 1 DIABETES
The medical condition that we want to highlight here is Type 1 diabetes.
Type 1 diabetes is otherwise known as Insulin Dependent Diabetes Mellitus (IDDM).
It is a prevalent autoimmune disease among Singaporeans aged 14 years old and above.
It was first diagnosed in children and teenagers.
It can occur at any age.
In Type 1 diabetes, the immune system attacks the beta cells in the pancreas that make insulin. In this case, beta cells are destroyed by the body’s own immune system.
As a result, the pancreas is unable to produce insulin. As time proceeds, these cells become insulin deficient.
Hence, Type 1 diabetes is a disease that causes the “auto-destruction” of the pancreatic beta cells that produce insulin.
Insulin is an important hormone that helps to reduce our body blood glucose level and increases glucose uptake into our bloodstream for energy.
It is required to metabolize glucose in the body to provide energy.
When insulin is not released or not produced at all, our body cells act as if the body is in the starvation state.
Blood glucose level in the body rises so much until it exceeds the kidney’s capacity to reabsorb glucose, causing glucose to spill into the urine.
P.S --> Please note that the type of diabetes a patient has is determined only by the cause -- fundamentally by whether the patient is insulin resistant (type 2) or insulin deficient without insulin resistance (type 1).
- CAUSES OF TYPE 1 DIABETES
The causes of type 1 diabetes are still not fully understood.
However, what have been found out for the causes of Type 1 diabetes are due to many factors as listed and elaborated below:
- Genetic predisposition (Inheritance) :
The vulnerability of getting Type I Diabetes is not shared by everyone, for not everyone infected by the suspected organisms develops type 1 diabetes. This has suggested presence of a genetic vulnerability. Hence, there is indeed an observed inherited tendency to develop type 1 Diabetes.
Type 1 Diabetes is a polygenic disease, meaning many different genes contribute to its expression.
Depending on locus or combination of loci, it can be dominant, recessive, or somewhere in between.
The strongest gene, IDDM1, is located in the MHC Class II region on chromosome 6, at staining region 6p21.
This is believed to be responsible for the histocompatibility disorder characteristic of type 1 Diabetes:
Insulin-producing pancreas cells (beta cells) display improper antigens to T Cells. This eventually leads to the production of antibodies that attack these beta cells. Weaker genes are also located on chromosomes 11 and 18.
Hence, the result is that the pancreatic beta cells are destroyed by these antibodies produced by our body's immune system. Thus the pancreatic beta cells are not able to produce hormone insulin that aids in blood glucose homeostalsis and the result is the symptoms displayed by Type 1 Diabetes as illustrated above.
- Viral infection :
Some theorize that type 1 diabetes is generally a virally triggered autoimmune response in which the immune system's attack on virus infected cells is also directed against the beta cells in the pancreas.
The mechanism of virus infection is as follows:
The person infected with a virus has a viral protein that is similar like a beta-cell protein. As a result of this, the T cells and antibodies destroy the beta-cell proteins and the viruses.
This results in the onset of Type 1 diabetes because beta-cells are depleted and causes insufficient or no insulin production in the body.
This is because in type 1 Diabetes, the pancreatic beta cells in the Islets of Langerhans are destroyed or damaged sufficiently to effectively inhibit endogenous insulin production.
Hence, the result is that lack of insulin means that blood glocose homeostalsis is affected in the body and the system will display all the symptoms as illustrated above.
The autoimmune attack may be triggered by reactions to an infection, for example by one of the viruses of the Coxsackie virusfamily or German measles as well as congenital rubella.
In the case of Coxsackie B , in the pancreas, this virus increases the expression of enzyme GADGAD which is a powerful auto antigen of the human body’s autoimmune response. Coxsackie B and GAD have the same sequence and this result in both to be mistaken for one another by the antibodies.
Viral infection in Coxsackie B virus changes memory of the T cells and antibodies causing them unable to recognize which cells are foreign and should be destroyed and unable to detect the continuous infection of beta cells because of viral antigens expressed in the beta cells.
In the case of Rubella Virus, it is proven by extensive and reliable medical studies and researches that people who infected with rubella virus in their fetal years 12-20% will get diabetes in 5 to 20 years. For adults with rubella, the cause of diabetes happens after they are infected with rubella virus which poses a threat to people who are genetically susceptible to rubella.
Hence, as can be seen, it shows how this virus plays a major impact and how it is related to Type 1 diabetes in people who are infected by such viruses.
- Antigens:
The development of Type I Diabetes involves specific proteins such as glutamic acid decarboxylase,insulin and islet cell antigen.
Islet of Langerhans produces the beta cells in pancreas which are responsible for destroying beta cells because they are autoantigens.
This means these proteins automatically attack auto antibodies on the beta cells.
Another explanation is that cytokines which are white blood cells known as T lymphocytes produces immune factors that destroys beta cells of pancreas. Examples of these cytokines are interleukin-1beta, tumor necrosis factor-alpha, and interferon-gamma.
- Some chemicals and drugs:
Some chemicals and drugs destroy pancreatic cells.
For example, Vacor (N-3-pyridylmethyl-N'-p-nitrophenyl urea), a rodenticide introduced in the United States in 1976, selectively destroys pancreatic beta cells, resulting in type 1 diabetes after accidental or intentional ingestion.
Another example is Zanosar. Zanosar is the trade name for streptozotocin, an antibiotic and antineoplastic agent used in chemotherapy for pancreatic cancer. Zanosar also kills beta cells, resulting in loss of insulin production.
-The autoimmune response is influenced by antibodies against cow's milk proteins:
A large controlled study published in 2006 suggested that infants who were never breastfed had a risk for developing type 1 diabetes twice that of infants who were breastfed for at least three months.
The explanation for this is that Bovine insulin is found in the milk of cows. The antibodies binding to bovine insulin appear to cross-react with human insulin. Bovine insulin is considered immunogenic because it differs from human insulin by 3 amino acids. Insulin-specific antibodies (ISA), those specific for IDDM, and increased T cell levels from exposure to cow’s milk have been found in those carrying diabetes associated HLA risk alleles.
Some studies have found bovine insulin antibody levels to decrease when human insulin was presented in the body.
Maternal milk contains colostrum with a variety of protective factors for the infant. Infants have an immature and easily penetrable gut system to digest and absorb food and enter the bloodstream.
However, Children gut system may accept or reject food and its dietary components in cow’s milk.
Beta-lactoglobulin and beta casein in cow’s milk have been shown to be related to IDDM. Some sections of albumin can react with beta-cell specific surface protein, which could contribute to islet cell dysfunction because of molecular mimicry.
When an antigen is present in the body, T cells latch onto a short segment, T cells can divide the antigen into macrophages and smaller protein fragments.The macrophages bring the fragments to the cell surface where capable T cells can bind to it. This activates the T cells, leading to stimulation in other areas to attack all proteins with similar amino acid segments. Bovine serum albumin has a short amino acid sequence similar to a beta cell surface receptor ICA69 and beta casein shares a similar sequence with a glucose transporter. If molecular mimicry occurs here, then presentation of beta casein in the body would lead to autoimmune destruction, hence causing the symtoms of Type I Diabetes as seen above.
-Others:
Other pancreatic problems including trauma, pancreatitis or tumors (either malignant or benign)can also lead to loss of insulin production
- SYMPTOMS
The symptoms of Type 1 diabetes are extreme thirst and hunger because the body cells act as if it is in hunger because insulin is not present or insignificant to reduce blood glucose levels. The person will urinate frequently because of drinking too much water to relieve thirst. The person will be tired. The person will lose weight as body cells are in state of hunger; this triggers protein, fat and glycogen to be broken down for energy. This result in body fats, glycogen muscles stores and protein which makes up our body cell membrane to decrease in amount resulting in weight loss. Another symptom is blurred vision.
- THINGS TO DO TO PREVENT WORSENING OF THIS CONDITION
In order to prevent the diabetic person’s condition from worsening, blood glucose level must be controlled by maintaining glycosylated hemoglobin (HbA1c) levels below 7%. This prevents blood vessel complication and nerve damage that leads to severe organ failures including the eyes, kidneys, and heart. By taking these steps, the person can prevent the risks of getting stroke and heart disease. As blood glucose control helps the heart, people with diabetes must control blood pressure, cholesterol levels which are risk factors of heart disease and can lead to worse complications such as stroke.
Alrighty people, enough of all that talking, here is another video link into Type I Diabetes, enjoy!
:http://www.youtube.com/watch?v=jy4F-140upI
~`~ Acknowledgements ~`~
We would like to thank our lecturer, Madam Kalpana for her help and guidance throughout our blog project. We would also like to express our most heartfelt appreciation and gratitude for her patience in imparting to us her valuable PBPN knowledge throughout this whole semester. Finally, we hope that our fellow classmates and whoever who drops by our "SkyMedics" blog had a good time and enjoyed reading our blog!Thank You!^_^
APA - STYLE REFENCE CITATIONS:
Diabetes-type-1. (2008). In About.com. Retrieved February 06, 2009, from About.com online: http://adam.about.com/reports/Diabetes-type-1.htm
Diabetes mellitus. (2009). In Encyclopædia Britannica. Retrieved February 06, 2009, from Encyclopædia Britannica Online: http://www.britannica.com/EBchecked/topic/160921/diabetes-mellitus
Lupus Erythem (2006). In National Institute of Arthritis and Musculoskeletal and Skin Diseases(NIAMS). Retrieved February 06, 2009, from NIAMS online: http://www.niams.nih.gov/Health_Info/Lupus/Lupus_Guide/chapter_1.asp#chp1_dd
Systemic Lupus Erythematosus. (2009). In MedicineNet.com. Retrieved February 06, 2009, from MedicineNet.com online: http://www.medicinenet.com/systemic_lupus/article.htm
What is lupus. (2009). In Lupus Foundation. Retrieved February 06, 2009, from Lupus Foundation online: http://www.lupussocal.org/AboutUs.htm
All ABOUT LUPUS (2009). In Lupus Associaiton Singapore. Retrieved February 06, 2009, from Lupus Assiciation singapire online: http://www.e-lupus.org/lupusall.html#what
WebMD Medical Reference from Healthwise.
Lupus Guide, Last Updated: 13th May 2008, Retrieved: 4th February 2009
URL: http://lupus.webmd.com/guide/lupus-overview-facts
Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical
David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
Systemic lupus erythematosus, Last Updated: 21th January 2008, Retrieved: 4th February 2009URL: http://adam.about.com/reports/Systemic-lupus-erythematosus.htm
An Ending Note:
The sky is not the limit. Reach for your dreams and make them a reality.