Session 1 Flashcards
What are the main differences between Type 1 and Type 2 diabetes?
- Type 1: cannot produce insulin due to beta cell failure (autoimmune attack which destroys beta cells); normally in younger people (below 30); rapid onset; in late presentation vomiting may occur because of ketoacidosis; have high glucose and ketones in urine and no insulin; treatment - inject insulin
- Type 2: insulin resistance - insulin is produced but the tissues are resistant (linked to obesity) (Type 2 later can have reduced beta cell function - insulin deficiency); many asymptomatic - picked up at routine health checks; older, overweight/obese patients; high glucose in blood/urine, no urinary ketones; treat with diet, exercise, drugs (eg a-glucosidase inhibitors and SGLT2s) and later insulin
Describe Diabetes
The blood glucose is too high (hyperglycaemia) which leads to the damage of small and large blood vessels, causing premature death from cardiovascular diseases
What is the typical triad of symptoms for diabetes?
- Polydipsia
- Polyuria
- Weight loss
What other symptoms is presented with diabetes mellitus?
- Blurring of vision
- Urogenital infections eg thrush
- Tiredness
- Weakness
- Lethargy
(Due to inadequate energy utilisation)
What tests are used to diagnose diabetes?
- Fasting glucose
- Oral glucose tolerance test
- HbA1c
What are some acute complications of diabetes?
- Hyperglycaemia: type 1- diabetic ketoacidosis
type 2 - hyperosmolar non-ketotic syndrome - Hypoglycaemia: coma
Give some examples of chronic complications of diabetes
- Macrovascular (eg cerebrovascular, cardiovascular, peripheral vascular): stroke, heart attack, intermittent claudication (cramping pain), gangrene
- Microvascular: retinopathy (blindness), nephropathy, neuropathy (foot ulceration)
What is the normal level of glucose in the fasting blood plasma?
- 5 mmol/L
What is the normal level of amino acids in fasting blood plasma?
- 2 mmol/L
What is the normal level of triacylglyerides in fasting blood plasma?
- 2 mmol/L
What is the normal level of cholesterol in the fasting blood plasma?
- 5 mmol/L
What is the normal level of fatty acids in fasting blood plasma?
- 0.5 mmol/L
What is the normal level of lactate and pyruvate in the fasting blood plasma?
- <1 mmol/L
What is the normal levels of bicarbonate and CO2 in the fasting blood plasma?
- 27 mmol/L
What is the normal level of urea in the fasting blood plasma?
- 5 mmol/L
What is the normal level of ammonium in the fasting blood plasma?
- 0.025 mmol/L
What is the body composition of a 70kg male?
- Carbohydrate: 1%
- Lipid: 16%
- Protein: 16%
What is the body composition of a 55kg female?
- Carbohydrate: 1%
- Lipid: 25%
- Protein: 15%
What is the normal dietary intake?
- Carbohydrate: 15%
- Lipid: 8%
- Protein: 5%
What is energy used for?
- Transport work across cell membranes
- Electrical work
- Mechanical work
- Biosynthetic work
- Osmotic work
(TEMBO)
What is the daily energy expenditure used for?
- Basal metabolic rate (BMR)
- Voluntary physical activity
- Diet-induced thermogenesis
How is BMI calculated?
- BMI = Weight (kg)/height (m)2
Define obesity
- The accumulation of excess body fat with a BMI above 30 that has an adverse effect of health and leads to reduced life expectancy and/or increased health problems
Define homeostasis
- A dynamic equilibrium that maintains a stable internal environment
Define cell metabolism
- The set of processes which derive energy and raw materials from food stuffs and use them to support repair, growth and activity of the tissues of the body to sustain life
What do high energy signals activate? Give examples
- Activate anabolic pathways
- ATP, NADH, NADPH, FAD2H
What do low energy signals activate? Give examples
- Activate catabolic pathways
- ADP, AMP, NAD+, NADP+, FAD
What is the average daily expenditure of a 70kg man and a 58kg woman?
- 70kg male: 12000 kJ/day (2800 kcal)
- 58kg female: 9500 kJ
How is creatine phosphate formed?
- creatine + ATP creatine phosphate + ADP
- catalysed by creatine kinase
What is creatine phosphate for?
- it is an energy store in cardiac and skeletal muscle
Describe Kwashiorkor and Marasmus
- Kwashiorkor: very low calories with very low protein but some carbohydrate; has a distended abdomen due to hepatomegaly (enlarge liver) and ascites (accumulation of fluid in peritoneal cavity); has generalised odema (low serum albumin leads to low oncotic pressure) and anaemia is common; also is apathetic, lethargic and anorexic (loss of appetite)
- Marasmus: very low calories in general; is emaciated with muscle wasting and loss of body fat; no odema (serum albumin and therefore oncotic pressure is normal); anaemia may occur; hair is thin and dry and diarrhoea is common
What do catabolic pathways do?
- Break down larger molecules into smaller ones (intermediary metabolites)
- Release large amounts of free energy
- Oxidative; releases H atoms; reducing power
What do anabolic pathways do?
- Synthesise larger important cellular components from intermediary metabolites
- Use energy released form catabolism (ATP)
- Reductive; uses H atoms released in catabolism
What are the products of catabolism?
- Building block materials eg sugars, amino acids, fatty acids
- Organic precursors (acetyl CoA) allows for interconversion of building block material
- Biosynthetic reducing power (NADH, NADPH)
- Energy for cell function (ATP)
