lecture about diabetes mellitus for undergraduated student, master student its include definition of diabetes, type 1 diabetes, type2, gestational, diagnosis criteria, complication, world day

1. Diabetes mellitus
Msc. murtadha adil
Master in clinical biochemistry

2. Glucose headline
 Monosaccharides are simple sugars that cannot be
hydrolyzed to a simpler form. The most common
include glucose, fructose, and galactose.
 Glucose is a simple sugar, or monosaccharide,
derived from the breakdown of dietary
carbohydrates
▹ the single-sugar units of carbohydrates, are
absorbed in the small intestine, whereas
other monosaccharides, including galactose
and fructose, are converted to glucose by the
liver.
▹ Glucose is the primary source of energy for
most body cells In responds to high glucose
levels.
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3. Carbohydrate metabolism
▹ Polymers carbohydrate in our food such as starch and glycogen is digested by Salivary amylase and
pancreatic amylase, which convert these no absorbable polymers to dextrins and disaccharides
▹ further hydrolyzed to monosaccharides by maltase, an enzyme released by the intestinal mucosa.
▹ Sucrase and lactase are two other important gut-derived enzymes that hydrolyze sucrose to glucose
and fructose and lactose to glucose and galactose.
▹ When disaccharides are converted to monosaccharides, they are absorbed by the gut and transported
to the liver by the hepatic portal venous blood supply.
▹ Glucose is the only carbohydrate to be directly used for energy or stored as glycogen.
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4. ”
▹ Glucose is a primary source of energy for humans.
▹ The nervous system, including the brain, totally depends on glucose from the surrounding
extracellular fluid (ECF) for energy.
▹ Nervous tissue cannot concentrate or store carbohydrates; therefore, it is critical to maintain a
steady supply of glucose to the tissue. For this reason, the concentration of glucose in the ECF
must be maintained in a narrow range.
▹ When the concentration falls below a certain level, the nervous tissue loses the primary energy
source and are incapable of maintaining normal function
▹ Galactose and fructose must be converted to glucose before they can be used.
▹ The ultimate goal of the cell is to convert glucose to carbon dioxide and water. During this
process, the cell obtains the high-energy molecule adenosine triphosphate (ATP) from inorganic
phosphate and adenosine diphosphate (ADP).
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5. ▹ After a carbohydrate‐
containing meal, it removes
about 70% of the glucose
load that is delivered via the
portal circulation. Some of
the glucose is oxidized and
some is converted to
glycogen for use as a fuel
under fasting conditions.
Glucose in excess of these
requirements is partly
converted by the liver to
fatty acids and triglycerides
▹ Gluconeogenesis
: is a metabolic pathway
that results in the
generation of glucose from
certain non-carbohydrate
carbon substrates
▹ glycogenolysis:
is the breakdown of the
molecule glycogen into
glucose, a simple sugar
that the body uses to
produce energy.
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6. 1- Insulin: peptide hormone produced by β-cells of Islets of
Langerhans of the pancreas. the primary hormone responsible
for the entry of glucose into the cell. It is synthesized by the
cells of islets of Langerhans in the pancreas. When these
cells detect an increase in body glucose, they release insulin.
The release of insulin causes an increased movement of
glucose into the cells and increased glucose metabolism.
its actions are:
a. Stimulates the uptake of glucose into tissues.
b. Promote the conversion of glucose to glycogen or fat for
storage
c. Inhibits gluconeogenesis & glycogenolysis.
d. Stimulates protein synthesis & inhibits protein breakdown
6 Hormones effect glucose level

7. 2- Glucagon is the primary hormone responsible for increasing glucose levels. It is synthesized by the α- cells of
islets of Langerhans in the pancreas and released during stress and fasting states. When these cells detect a
decrease in body glucose, they release glucagon. Glucagon acts by increasing plasma glucose levels by
glycogenolysis in the liver and an increase in gluconeogenesis. It can be referred to as a hyperglycemic agent
glucagon polypeptide hormone secreted by α-cells of the pancreas; its actions are:
a. Stimulate the production of glucose in the liver by glycogenolysis and gluconeogenesis.
b. Inhibits glycolysis.
c. Depresses glycogen synthesis.
3- somatostatin
4- cortisol
5- growth hormone
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Hormones effect glucose level

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is a group of metabolic diseases characterized
by hyperglycemia resulting from defects in
insulin secretion, insulin action, or both. The
chronic hyperglycemia of diabetes is associated
with long-term damage, dysfunction, and failure
of different organs, especially the eyes, kidneys,
nerves, heart, and blood vessels.

9. History
Diabetes comes from the Greek ‘to pass through’, and mellitus from the Latin word meaning ‘sweetened
with honey’. Ancient Egyptians described features similar to diabetes mellitus around 3000 years ago
but the actual term ‘diabetes’ was only first used by the physician in the 2nd century AD. Later, in 1675,
‘mellitus’ was added by Thomas Willis, a physician who re-discovered the urine’s sweet taste. A major
turning point in the history of diabetes was the discovery and use of insulin by Banting and Best in 1921
The first oral hypoglycaemic agents were marketed in 1955
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10. Type 1 (insulin-
dependent) diabetes
mellitus (IDDM)
Gestational diabetes
mellitus (GDM)
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Type 2 (non-insulin-
dependent) diabetes
mellitus (NIDDM).
CLASSIFICATION OF DIABETES MELLITUS

11. Symptom of diabetes
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12. 12 - Name : juvenile diabetes, type 1 diabetes mellitus, insulin-dependent
- Affect : Approximately 5% to 10% of all cases of diabetes mellitus.
- Symptom : Patients usually have sudden onset of symptoms (eg, polyuria, polydipsia, rapid weight loss).
- Cause : The main cause of this type is lack of insulin (insulinopenia) (a deficiency of insulin) that may result
from destruction of pancreatic islet β-cells, Some forms of type 1 diabetes have no known etiologies called
Idiopathic Diabetes
- Most patients have antibodies that identify an autoimmune process
- T1DM is an autoimmune disease with both genetic and environmental factors playing an important part in its
development. Genetic factors are thought to account for around 30% of the susceptibility risk
- the peak incidence occurs in childhood and adolescence the gut, as the result of hydrolysis or hepatic conversion
of a variety of ingested Carbohydrates hepatic and some other glycogen stores (glycogenolysis) new synthesis
from precursors (gluconeogenesis)
- Type 1 diabetes diagnosis by observe symptoms like polyuria (frequent urination), polydipsia (excessive thirst),
and polyphagia (excessive hunger), often triggered by stress or an illness. fatigue, weight loss, and weakness.
- The diagnosis is confirmed by a fasting blood glucose (FBG) greater than or equal to 126 mg/dl, commonly
accompanied by ketoacidosis.
Type 1 Diabetes Mellitus

13. 13 Gestational diabetes mellitus
(GDM)
any degree of glucose intolerance with an onset or first
recognition during pregnancy, GDM is diabetes mellitus (DM)
diagnosed in the second or third trimester of pregnancy that does
not clearly meet the criteria of overt DM, Gestational diabetes
mellitus affects up to 14 % of all pregnancies Untreated GDM
carries a risk for both the mother and child and is associated with
serious short- and long-term consequences, including neonatal
and obstetric complications during pregnancy and childbirth (e.g.
macrosomia, birth injury, cesarean section) and a predisposition
to obesity and DM in the offspring in later life

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Name: Called adult diabetes, non–insulin-dependent diabetes, type 2 diabetes
prevalence: accounts for approximately 90% of all cases of diabetes
affect: occurrence later in life with a gradual onset, usually after 40 years of age.
Insulin concentrations may be normal, decreased, or increased, and most people with this form of diabetes have
impaired insulin action
Type 2 diabetes is characterized by insulin resistance and progressive hyperglycemia
many individuals with type 2 diabetes have symptoms of polyuria and polydipsia of several weeks' duration.
Polyphagia may be present, but is less common.
Type 2 diabetes result from combination of insulin resistance and dysfunctional β cells, ketoacidosis is less
likely to occur.
Obesity is commonly associated, and weight loss alone usually improves hyperglycemia in these persons
Type 2 Diabetes Mellitus

15. Insulin resistance
 Insulin resistance: is the decreased ability of target tissues, such
as liver, adipose, and muscle, to respond properly to normal (or
elevated) circulating concentrations of insulin. For example,
insulin resistance is characterized by uncontrolled hepatic
glucose production, and decreased glucose uptake by muscle
and adipose tissue.
 dyslipidemia (high triglyceride and low high-density lipoprotein
[HDL] cholesterol), and hypertension. Individuals with this
syndrome are at increased risk for cardiovascular disease.
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is a low plasma glucose state. Hypoglycemia is the acute complication
of diabetes mellitus and the commonest diabetic emergency and is
associated with considerable morbidity and mortality. It can be caused
by too much insulin intake or oral hypoglycemic agents, too little food,
or excessive physical activity. Symptoms result from activation of the
autonomic pathways and from inadequate glucose delivery to the
central nervous system. This explains the clinical features of
hypoglycemia that are, in the acute form, intermittent episodes of
sweating, tachycardia, anxiety, dizziness, slurred speech, double vision,
and confusion, with complete recovery on restoration of plasma
glucose to normal levels. The plasma glucose level in hypoglycemic
patients decreases well below 2.2 mmol/L, often to less than 40 mg/dL.
Hypoglycemia can be divided into reactive postprandial hypoglycemia
and fasting hypoglycemia. Overall, hypoglycemia is most commonly
observed in patients being treated for diabetes.
Hypoglycemia

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Reactive hypoglycemia: may occur after
meal Normally, the ingestion of a high
carbohydrate meal increases the plasma
glucose level and stimulates the release of an
appropriate amount of insulin. In reactive
hypoglycemia, the peak concentration of
insulin is inappropriately high and causes the
plasma glucose level to decrease below the
reference range. Reactive hypoglycemia is
diagnosed if there are hypoglycemic
symptoms, and a plasma glucose level below
50 mg/dL following a high-carbohydrate
meal.
Fasting Hypoglycemia Fasting hypoglycemia is
diagnosed from a blood sample that shows a
blood glucose level below 50 mg/dL after an
overnight fast, between meals, or after physical
activity. Causes and Treatment Causes of fasting
hypoglycemia include certain medications,
alcoholic beverages, critical illnesses, hormonal
deficiencies, some kinds of tumors, and certain
conditions occurring in infancy and childhood

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is blood glucose greater than 125 mg/dL while fasting and greater than 180 mg/dL
2 hours postprandial. A patient has impaired glucose tolerance, or pre-diabetes, with a
fasting plasma glucose of 100 mg/dL to 125 mg/dL. A patient is termed diabetic with a
fasting blood glucose of greater than 125 mg/dL. When hyperglycemia is left untreated,
it can lead to many serious life-threatening complications that include damage to the
eye, kidneys, nerves, heart, and peripheral vascular system. it is vital to manage
hyperglycemia effectively and efficiently to prevent complications of the disease and
improve patient outcomes.
Hyperglycemia

20. complication of diabetes
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Uncontrolled hyperglycemia lead to multiple, primarily vascular, complications that affect small vessels
(microvascular)
- Retinopathy
- Nephropathy
- Neuropathy
Or, large vessels (macro vascular)
- Angina pectoris and myocardial infarction
- Transient ischemic attacks and strokes
- Peripheral arterial disease

21. Diabetic retinopathy
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The retina is the most vascular region in the body, as
it needs high oxygen to convert light into electrical
energy in the rods and cones.
Diabetic retinopathy is the most common form of
diabetic eye disease. Diabetic retinopathy usually
only affects people who have had diabetes (diagnosed
or undiagnosed) for a significant number of
years. Chronic hyperglycemia may cause
microvascular damage to the retinal vessels, resulting
in edema and/or hemorrhage into the retina or the
vitreous humor because of vascular permeability.
Diabetic retinopathy is a major cause of blindness.
The degree of retinopathy is highly correlated with
Duration of diabetes, Blood glucose levels , BP
levels. The risk of developing diabetic retinopathy is
known to increase with age as well with less well
controlled blood sugar and blood pressure level.

22. Diabetic nephropathy
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is one of the most important microvascular
complications, whose earliest manifestation is the
presence of minute amounts of urinary protein (micro
albumin) , It is characterized by changes in
glomerular cause glomerular hypertension and
progressive decline in glomerular filtration rate.
Systemic hypertension may accelerate progression.
The disease is usually asymptomatic until nephrotic
syndrome or renal failure develops.
These microalbumin cannot be detected in routine
urinalysis, but is detectable by specific testing. If the
detection can be done in the earlier phase, the
progression of nephropathy can be prevented.

23. Diabetic neuropathy
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is the result of nerve ischemia due to microvascular disease, direct effects of
hyperglycemia on neurons, and intracellular metabolic changes that impair nerve
function. It may be associated with foot ulcers, amputations, non-healing skin wounds,
and sexual dysfunction. The neuropathy results in loss of protective sensation in the
feet, which leads to callous formation, ulceration and other injury, and may also result
in the infection of the skin (e.g. cellulitis) and/or bones of the foot (e.g. osteomyelitis)
and gangrene. Sexual dysfunction usually occurs in young-aged diabetic patients
because of oxidative stress in cavernous tissues.

24. Cardiovascular disease
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Cardiovascular disease is a primary cause of
mortality and morbidity in both prediabetes and
T2DM, the potential mechanism for which is
oxidative stress that has important effects on
atherogenesis and may contribute to low-density
lipoprotein (LDL) oxidation. Prevention of
premature cardiovascular events involves
complex interactive treatments with
antihypertensives, lipid-lowering agents, and
routine low-dose aspirin administration.

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During carbohydrate deprivation caused by decreased carbohydrate utilization such as occurs
during diabetes starvation, fasting, or prolonged vomiting, blood levels of ketones derived from
lipid breakdown increase to meet energy needs.
The three ketone bodies are:
• Acetone (2%)
• Acetoacetic acid (20%)
• 3-β-Hydroxybutyric acid (78%)
Ketonemia refers to the accumulation of ketones in blood, and ketonuria refers to
accumulation of ketones in urine. Measurement of ketones is recommended for patients with
type 1 diabetes during acute illness, as well as in other conditions, including stress, pregnancy,
and extremely elevated blood glucose levels.
Ketone Bodies

26. 420,000,000
Diabetic patient in 2014
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27. Symptoms of diabetes plus a
random plasma glucose level of
more than 200 mg/dL, (2) a fasting
plasma glucose of more than 26
mg/dL
a fasting plasma glucose
of 126 mg/dL or more
an oral glucose tolerance test (OGTT)
with a 2-hour postload (75-g glucose
load) level 200 mg/dL, each of which
must be confirmed on a subsequent
day by any one of the three methods
The preferred test for diagnosing
diabetes is measurement of the fasting
plasma glucose level.
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Criteria for the Diagnosis of Diabetes Mellitus
Three methods of diagnosis are suggested:

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Risk for developing gestational diabetes
 Had gestational diabetes during a previous pregnancy
 Are overweight
 Are more than 25 years old
 Have a family history of type 2 diabetes
 Have a hormone disorder called polycystic ovary
syndrome (PCOS)
Risk factors
Risk for developing type 2 diabetes
 Have prediabetes
 Family history
 Are overweight
 Are 45 years or older
 Have a parent, brother, or sister with type 2 diabetes
 Are physically active less than 3 times a week
 race

29. Diabetes control
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• Eating a healthy diet with plenty of fruit and
vegetables, maintaining a healthy weight, and getting
regular physical activity can all help. Other tips
include:
• Keep track of your blood sugar levels to see what
makes them go up or down.
• Eat at regular times, and don’t skip meals.
• Choose foods lower in calories, saturated fat, trans fat,
sugar, and salt.
• Track your food, drink, and physical activity.
• Drink water instead of juice or soda.
• Limit alcoholic drinks.
• For a sweet treat, choose fruit.

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31. World diabetes day
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