Module 3 Flashcards
1
Q
Metabolism
A
- term that describes the total balance of energy requirements of the body.
- Metabolism is the process by which macromolecules from our food are converted into energy.
- Our bodies need this energy to do everything from moving to thinking and growing.
2
Q
Metabolism describes how our bodies…
A
- Take in macromolecules
- Store macromolecules
- Break macromolecules down for energy/ recycling, and
- Create new macromolecules as they’re needed
When one or more of these processes are disturbed, it can lead to a metabolic disorder
3
Q
Anabolic pathway
A
- anabolic pathways create new, more complex macromolecules out of smaller units or molecules.
- requires energy.
- used by cells in our body to grow or repair damage
4
Q
Catabolic pathway
A
- break down macromolecules into smaller units or molecules
- generate energy in the process
5
Q
Carbohydrates
A
- include sugars, glycogen, fiber and starches.
- There are simple (bad) or complex (healthy carbohydrates.
- Glycogen is broken down into glucose or blood sugar.
- Glucose is the primary type of sugar that our bodies use for energy.
- It can’t enter the cells via plasma membrane by itself, so it needs transporters.
- store glucose in the form of glycogen until needed.
*first reservoir of stored energy that the body uses
6
Q
Lipids
A
- lipids is a general term for all types of fats (triglycerides, oils, fats and cholesterol) in the body.
- Because fats and water don’t mix well, lipids are associated with transporter proteins to get them where they’re needed
- Deposits of fats in the body are stores within adipocytes or fat cells known as adipose tissue
*second reservoir of stored energy that body uses
7
Q
Proteins
A
- proteins consist of chains of amino acids. (play a part in central dogma)
- Unlike glycogen and lipid stores, proteins are only broken down primarily as an energy source during periods of starvation, since proteins serve other important functions
8
Q
Nucleic Acid
A
- DNA and RNA are examples of nucleic acids. (critical for central dogma)
- Not used for energy production.
- Make up molecules ATP, and GTP which are used as energy currencies to drive chemical reactions in the body
9
Q
Metabolism Across the Body
A
- Food intake: how much food you consume
- Food expenditure: how much physical activity you get
- Fat stores: how much fat you have stored
- CNS: your basal metabolic rate
10
Q
metabolism and Equilibrium
A
- metabolism is at equilibrium when there are equal amounts of anabolic and catabolic processes taking place.
- This is the state that your body tries to achieve at all times.
11
Q
metabolism: anabolism
A
- lack of exercise and continued food intake will favour the storage of sugars and fats via anabolic processes.
- Prolonged time spent in this imbalance may lead to weight gain as fat is stored in adipose tissue and basal metabolism rates drop.
- Effects: adipose storage, high blood sugar, lower basal metabolic rate
12
Q
metabolism: Catabolism
A
- exercise and fasting will drive catabolic processes and shift balance to a state where hormones signal for stored sugars and fats to be broken down and enter the circulation where they’re absorbed by cells in need of energy.
- Prolonged time spent expending energy leads to weight loss, but also induces hunger as blood sugar concentrations gradually drop.
- Effects: adipose breakdown, low blood sugar, induced hunger
12
Q
insulin
A
- Insulin is a hormone produced by beta-cells, specialized cells in the pancreas.
- responsible for maintaining healthy levels of glucose in the blood.
13
Q
what is the preferred short term fuel for most tissues
A
glucose
14
Q
Insulin binding
A
- insulin binds to the insulin receptor on the extracellular surface of cells.
- leads to the activation of the receptor and signals which result in increases in anabolic activity
15
Q
Glucose transport
A
- At the same time, insulin stimulates the movement of glucose transporters from endosomes inside the cell to the plasma membrane
- Allow glucose to enter the cell and be used for energy
16
Q
why can’t glucose enter the cell and not be metabolized
A
there are no glucose transporters on the plasma membrane of the cell
17
Q
Lipid transport and Metabolism
A
Changes in blood lipid levels such as the increases in triglycerides and cholesterol associated with obesity, are known risk factors for many different diseases
18
Q
Introduction to Plasma Lipoproteins
A
- Lipids (cholesterol and triglycerides) are transported in the bloodstream with plasma lipoproteins.
- Plasma lipoproteins form spherical complexes (cholesterol) around lipids to transport them in the bloodstream.
- This encasing of lipid molecules within the lipoproteins makes the lipids water-soluble and transportable through the bloodstream
- Lipoproteins also play important roles in lipid absorption by ensuring the right molecules get to where the body needs them, and to a lesser extent a role in lipid breakdown or synthesis as required
19
Q
Forms of Lipoprotein for Lipid Transport
A
low density lipoproteins (LDL) and high density lipoproteins (HDL)
20
Q
low density lipoproteins (LDL)
A
LDL is used to transport cholesterol to tissue and is the “bad” cholesterol. (want it low)
21
Q
high density lipoproteins (HDL)
A
HDL is used to transport extra cholesterol back to the liver and is the “good” cholesterol. (want to be higher)
22
Q
what levels of LDL and HDL cause increased risk of heart disease
A
Increased triglycerides, LDL and low HDL = increased risk of heart disease
23
Q
Metabolic Disorders: The Obesity Epidemic
A
- accumulation of excess body fat.
- past: survival required a higher level of activity, leading to genetic tendency to store excess calories as fat for survival
-present: sedentary lifestyle and abundance of food has contributed to an epidemic of obesity - Childhood obesity is 3x in the past 30 years
- In 2016, more adults overweight than under
- increase in developing related diseases( type 2 diabetes, cardiovascular disease, hypertension, cancer and arthritis)
24
Subcutaneous Fat (pear)
- majority of fat (80-90%) stored in the subcutaneous depots in the abdomen, hip and thigh regions.
- Lower body fat cells in biological females are larger and store fat efficiently, but release it more slowly.
- Results in pear-shape or lower body obesity
- much lower associated risk of metabolic diseases
25
Visceral Fat (apple)
- 10–20% of fat is stored as visceral fat in the abdomen ( in visceral adipose tissue)
- Visceral fat breaks down faster and is more hormone-sensitive.
- More common in biological males.
- Excess visceral fat increases hormone signals, raising disease risk.
- Linked to apple-shaped (upper body) obesity.
- Increases risk of high blood pressure, insulin resistance, diabetes, and heart disease.
- Waist circumference is an important risk factor to monitor.
26
Metabolic syndrome
- greatly increases the risk of many chronic illnesses.
- diagnosed when a patient has at least ⅗ risk factors
27
risk factors of metabolic syndrome
- visceral obesity
- high blood sugar
- hypertension (high blood pressure)
- high triglycerides
- low HDL cholesterol
28
Mariannes Story
- 49 yo woman, struggled with weight for most of her life, family history of diabetes, both father and uncle have
- This year her results were cause for concern with a high BMI and waist circumference. (above normal).
29
Introduction to Diabetes
- metabolic disease with high blood sugar (glucose).
- Over time, damages the eyes, heart, nerves, blood vessels, and kidneys.
- Insulin is a hormone that controls blood sugar levels.
- The pancreas releases insulin when blood sugar is high.
- Insulin signals cells to take in glucose for energy or storage, lowering blood sugar.
Diabetes happens when:
- The body doesn’t make enough insulin
- Cells don’t respond properly to insulin.
30
Diabetes stats
1 in every 11 people have diabetes with the number increasing every year
8.5% of men and 7.5% of women have been diagnosed with diabetes
Type 2 diabetes is responsible for 90% of diagnosed diabetes
31
Impact of Diabetes on Indigenous Communities
- Indigenous communities in Canada face higher rates of diabetes than non-Indigenous people.
This is due to:
- Historic and ongoing colonial policies
- Limited access to healthy, affordable food
- A strong genetic risk for type 2 diabetes
32
Colonialism and the Indian Act
- Colonization greatly reduced access to healthcare and resources for Indigenous Canadians.
- The Indian Act of 1876 disrupted traditional lifestyles and governance.
- Forced Indigenous people into permanent settlements and farming.
- Shifted communities from active lifestyles to more sedentary ones.
- Traditional diets and healing practices were replaced by Western medicine.
33
Type 1 diabetes
- Happens when the body stops making insulin, usually due to an autoimmune disorder that destroys beta cells.
- Without insulin, cells can’t absorb glucose from the blood.
- Insulin replacement is essential for managing this type of diabetes.
34
Type 2 diabetes
- Caused by both insulin resistance and poorly working beta cells.
- Cells don’t respond to insulin, so less glucose is absorbed from the blood.
- Most people with type 2 diabetes don’t need insulin to survive.
- Early symptoms are milder than in type 1, since some insulin is still produced.
35
Insulin Resistance and Type 2 Diabetes: healthy
β- cells in pancreas release insulin into the bloodstream in response to an increase in blood glucose
36
Insulin Resistance and Type 2 Diabetes: Excessive glucose intake
- Eating more food than needed causes a spike in blood sugar.
- The pancreas responds by releasing more insulin.
- This helps cells absorb the extra glucose from the blood.
37
Insulin Resistance and Type 2 Diabetes: Continued glucose intake
- Eating more than necessary over time causes changes in insulin receptors.
- Receptors bind less insulin, allowing less glucose into cells.
- This marks the beginning of insulin resistance.
38
Insulin Resistance and Type 2 Diabetes: Insulin resistance
- Tissues like the liver, fat cells, and muscles become less responsive to insulin.
- This leads to high blood glucose (hyperglycemia).
- The decrease in glucose uptake by muscles and fat contributes to the high blood sugar.
39
Insulin Resistance and Type 2 Diabetes: β- cell damage
- To compensate for insulin resistance, the pancreas produces more insulin.
- This overworks the beta cells, which can become damaged or stop functioning.
- When beta cells fail, not enough insulin is made, leading to uncontrolled blood glucose (hyperglycemia).
- This is common in late-stage type 2 diabetes.
40
Onset and Diagnosis of Type 2 Diabetes
- Key indicators of diabetes: high fasting blood glucose and high hemoglobin A1C.
- Diabetes develops slowly, often without obvious symptoms.
Common symptoms of type 2 diabetes:
Polyuria - frequent urination
Polydipsia - excessive thirst
Polyphagia - excessive hunger
41
Metformin
- Metformin (Glucophage) is the first-line medication for type 2 diabetes, especially for overweight patients.
- It activates pathways that are important for both sugar and fat metabolism.
42
Progression to Severe Type 2 Diabetes
Managing early type 2 diabetes is key to preventing disease progression.
Effects of type 2 diabetes on the body:
Eyes: Vision loss from retinal damage.
Heart: Higher risk of heart disease, heart attacks, and strokes.
Pancreas: May stop producing insulin; medications or insulin therapy may be needed.
Kidneys: High blood sugar damages kidney blood vessels and function.
Feet: Nerve damage (peripheral neuropathy) can lead to unnoticed injuries, ulcers, and in severe cases, amputation.
43
Diabetes-Specific Risk Factors
Age:
- Type 1: Can occur at any age, but often in young children.
- Type 2: More common in people 45+, but rising in younger ages due to childhood obesity.
Lifestyle:
- Type 1: Not linked to lifestyle; no known way to prevent it.
- Type 2: Strongly linked to poor diet and low physical activity. Risk can be reduced with healthy eating and regular exercise.
Family History:
- Having a family member with type 1 or type 2 diabetes increases your risk of developing that type.
44
Social Determinants of Health in Obesity and Diabetes
- Social determinants of health are factors that affect a person’s health in positive or negative ways.
- These include things like gender, housing, food security, employment, income, and access to healthcare.
- Many Indigenous people in Canada face poor social determinants of health.
- Several barriers limit access to health-promoting conditions.
45
Lack of Health-Promoting Conditions in Canada: Availability of Health Services
- Integrating Indigenous culture and healing into healthcare improves access and effectiveness.
- Helps healthcare workers understand the colonial roots of current practices.
The Indigenous Diabetes Health Circle (Ontario) created a resource on:
- Traditional Indigenous diets
- Today’s diets and healthy food choices
- A comparison of a healthy diet to that of a bear—symbolizing strength and being disease-free.
46
Lack of Health-Promoting Conditions in Canada: adequate housing
- Indigenous Peoples face much higher rates of homelessness in cities:
- 1 in 15 Indigenous individuals vs. 1 in 128 in the general population.
- Over 40% of homes on reserves need major repairs.
- Overcrowding on reserves is 6 times higher than off-reserve.
- Poor housing security forces many to choose between paying for shelter or buying healthy food.
47
Lack of Health-Promoting Conditions in Canada: safe working conditions
- Indigenous Canadians often work in higher-risk jobs, leading to more workplace injuries and hospitalizations.
- They are more likely to have seasonal or part-time work, with fewer job benefits.
- Job loss or injury reduces financial stability.
- This makes it harder to afford healthy food and necessary medications.
48
Lack of Health-Promoting Conditions in Canada: nutritious foods
Indigenous households face higher risk factors for food insecurity, such as:
- Extreme poverty
- Single motherhood
- Reliance on social assistance
- Rental housing
- Indigenous Peoples are 4 times more likely to experience hunger than non-Indigenous Canadians.
- Hunger makes it harder to maintain good health.
Programs like Nutrition North Canada aim to reduce these gaps by:
- Subsidizing food costs
- Supporting traditional hunting and harvesting
- Promoting culturally appropriate nutrition education
49
Ben case study
- 55 yo man that has been brought to the emergency department by ambulance.
- Had sudden onset of right sided weakness and speech difficulty; signs of stroke
- Diagnosed with type 2 diabetes 4 years ago.
- Doctor explained he's at risk for stroke, so the family was educated and his partner called 911 right away.
50
Heart Disease at a Glance
- Heart disease includes many conditions that affect heart and blood vessel health.
- Heart attacks are sudden and can be fatal, but are less common.
- Other heart conditions, like hypertension (high blood pressure), are more common and can lead to serious problems.
- Hypertension affects 1 in 4 Canadians.
- Indigenous Peoples have heart disease rates up to 50% higher than the general population.
- Stroke death rates are twice as high among Indigenous Canadians.
- These differences are linked to limited healthcare access and poor social determinants of health.
Other heart conditions include:
- Atherosclerotic disease
- Heart valve disease
- Arrhythmias (irregular heartbeat)
- Heart infections
- Heart failure
51
Atherosclerosis
- type of heart disease where arteries thicken and narrow.
- Caused by inflammation and plaque buildup in the artery walls.
- Often starts early in life, so it’s hard to measure how common it is.
- Severe atherosclerosis can lead to heart attacks and strokes
- occurs at sites where blood vessels are repeatedly damaged
52
lumen
where blood flows
53
endothelium
- first layer surrounding the lumen.
- Made up of endothelial cells
54
blood vessel wall
Layers of smooth muscle cells sandwiched between tissues
55
atherosclerosis: injury
- Damage to blood vessels happens when blood flow causes friction.
- Triggers include smoking, high blood pressure, and viruses.
- Normally, damage is quickly repaired.
- But if LDL ("bad") cholesterol is high, it builds up at damaged sites.
- LDL gets absorbed into the artery wall beneath the endothelial cells, starting plaque formation.
56
Atherosclerosis: Infiltration
- LDL accumulation causes more inflammation.
- This inflammation recruits platelets (blood clot helpers) and immune cells.
- These cells enter and infiltrate the blood vessel wall, worsening the damage.
57
Atherosclerosis: Lipid Buildup
- Immune cells try to remove LDL buildup by engulfing lipoproteins.
- Instead of clearing the buildup, LDL-filled immune cells die (apoptosis), causing more inflammation.
- This inflammation, along with lipid debris, forms the first visible signs of atherosclerotic plaque.
58
Atherosclerosis: complete plaque
- Inflammation, lipid buildup, and immune cell infiltration continue, leading to an atherosclerotic lesion.
- Collagen, debris, and more immune cells increase the plaque size.
- Lesions can narrow or block blood vessels or weaken the vessel wall, causing bleeding.
- If the plaque ruptures, a blood clot can dislodge and block other vessels (embolism).
59
Socioeconomic Risk Factors and Health Inequities with heart diseases
- First Nations, Métis, and Inuit Peoples are at a higher risk for heart disease and stroke compared to non-Indigenous Canadians.
- Social determinants of health (e.g., access to care, income, social support) contribute to this increased risk.
- A 2018 study found that Indigenous communities across Canada have a greater risk for cardiovascular disease (CVD) compared to non-Indigenous communities.
- However, the risk varies greatly between individual Indigenous communities.
- Communities with poor access to primary care, lower income, and less social support have a higher risk of CVD.
- Communities with better access to care, higher income, and stronger social support have lower CVD risk.
- The study suggests that modifiable social factors, rather than genetics or physiology, play a larger role in the differences in CVD risk.
60
Protective Factors in Indigenous Communities
- Indigenous communities with higher income, employment, education, social support, and access to affordable healthcare had a lower risk of cardiovascular events.
- These factors are considered protective factors, as they reduce the likelihood of developing disease.
- Risk factors increase the chance of experiencing health issues or developing a disease.
- Protective factors lower the risk of disease.
61
The Burden of Metabolic Disorders
- Metabolic diseases (like diabetes and heart disease) are a major burden, second only to cancer in developed countries like Canada.
- These diseases are considered national and global pandemics.
- Novel treatments may slow or reverse the effects of metabolic diseases, but prevention and early intervention are more effective for managing these disorders right now.
- Public health initiatives that help patients manage their care could significantly improve disease incidence, prevalence, and survival faster than biomedical research alone.
62
Improving the Patient Journey for Metabolic Disease: treatment
- Various initiatives aim to address inequities in social determinants of health for Indigenous Peoples, offering hope for better access to diabetes management.
- Diabetes is a major focus in metabolic disease research.
- Since diabetes increases the risk of other medical conditions, breakthroughs in this field could improve patient outcomes and save many lives.
63
Improving the Patient Journey for Metabolic Disease: monitoring
- Advanced atherosclerosis is treated with surgical interventions, which carry significant risks.
- The future of treatment aims to reduce reliance on surgery in favour of non-invasive alternatives.
