Biochem Flashcards
Appetite, energy expenditure, genotype, digestion, metabolism, availability of food, customs and presence of disease.
Factors that contribute to the state of nutrition
Important regulators of food intake
Leptin, Ghrelin and Insulin
Circulates, in the body, at levels proportional to body fat.
Leptin
Adipose tissue produces
Adipokines
Regulate metabolic processes to meet the body’s needs.
Adipokines
produces adipokines that regulate metabolic processes to meet the body’s needs.
Adipose tissue
AMP and AMP/ATP regulate
AMP-activated kinase (AMPK)
Senses cellular energy levels
AMPK
regulate AMP-activated kinase (AMPK) that senses cellular energy levels.
AMP and AMP/ATP
regulates rate-limiting enzymes in energy-producing and using pathways.
AMPK
inhibit energy-utilizing pathways and stimulate energy generating pathways.
High levels of AMPK activity
Increased _______ increases appetite
Ghrelin
favors accumulation of lipids in the visceral fatty tissue.
Ghrelin
Estimated average requirements (EAR) for calories changes with
Age and sex
Estimated daily protein requirements vary with
Age and sex
The ideal amount of calorie intake in a day is equal to the
Calorie utilization for that day
for a nutrient is a value that is adequate for the great majority of individuals
Recommended daily allowance (RDA)
Reflects amount that is adequate for half of the population.
Estimated average requirement (EAR)
Different nutrients have different
energy content
Has the highest energy content per weight.
Fat
has a high-energy content.
Alcohol
correlated with an increase in the use of high fructose corn syrup.
Increases in obesity
made by breaking down cornstarch into glucose using amylase followed by conversion to fructose with glucose isomerase.
High fructose corn syrup
There are several potential health issues associated with comsumption of high fructose corn syrup including:
mercury exposure, hypertension, elevated cholesterol, long-term liver damage, increased risk of diabetes and weight gain and obesity
Protein-calorie malnutrition causes a number of health problems including:
decreased protein synthesis and glucose transport, fatty liver, liver necrosis and fibrosis, depression, hypothermia, compromised immune function and would healing, decreased cardiac and renal function, loss of muscle.
associated with an increased risk for several conditions including: type 2 diabetes, hypertension and stroke, dyslipidemia, gall stones, respiratory disorders, musculoskeletal disorders and several cancers including breast, endometrial, ovarian, gall bladder and colon.
Obesity
not essential and provide no benefit to human health.
Trans fatty acids
increase levels of LDL cholesterol (bad cholesterol).
Saturated fats
increase levels of LDL and also lower levels of HDL (good cholesterol); thus increasing the risk of coronary heart disease
Trans fats
Prime side for drug metabolism
Liver
-also in plasma kidney, lung, gut wall
1)Increase in drug hydrophilicity and ability to be excreted (hepatic) 2)Metabolic products are less pharmacologically active than the substrate drug 3)Inactive prodrugs converted to their active forms (hepatic)
3 potential outcomes of drug metabolism
can decrease effectiveness of drugs that target DNA.
An increase in DNA repair activity
results from an increase in the amount of transporter proteins that can pump many different drugs out of the cell.
Multidrug resistant
4 essential processes needed to develop from a single cell into a multicellular organism:
- Cell proliferation
- Cell specialization
- Cell interaction
- Cell movement
Where is Ghrelin produced?
Stomach
stimulates the brain giving rise to an increase in appetite
Ghrelin
favors the accumulation of lipids in visceral fatty tissue
Ghrelin
R groups are on the same side
CIS
R groups are on opposite sides
TRANS
metabolized in LIVER intestine, testis, kidney, skeletal muscle, fat tissue and brain
Fructose
The vast majority of the cell cycle period
G0
Cell duplicates its contents
G1
Where there is most variability among cell types, why some divide faster than others
G1
Chromosomes duplicated and checked for errors
Time spent in S and G2
The actual division into daughter cells
M
How long does Mitosis take
1 hour
Chomosomes attatched to spindle
Metaphase checkpoint
Is environment favorable
G1 checkpoint
Is environment favorable and is DNA replicated
G2 checkpoint
Normal cellular genes that function in cell proliferation
Protooncogenes
Mutated protooncogene
Oncogene
Antiproliferative genes
Tumor suppressor gene
Dominant: cellular transformation occurs with a mutation by only one allele
Protooncogene
Recessive: loss of expression of both alleles leads to uncontrolled cell division
Tumor suppressor gene
Often involved in checkpoint signaling
Protein Tyrosine Kinases
Enzymes that transfer the gamma (Y) phosphate from ATP to a tyrosine on a target protein
Check points and PTKs
Target that phosphorylates itself
Intrinsic
Phosphorylates another protein
Extrinsic
Signals for proliferation
Growth factors
Several work in concert to stimulate cell division
Growth factors
Can induce cell growth but not division
Growth factors
What do growth factors bind to?
Specific cell receptors
What are growth factors involved in
Signal transduction pathways
Paradigm of growth factors
PDGF
Due to PDGF, there is an increase in
Intracellular calcium ions
PDGF allows reorganization of actin stress fibers to facilitate
attatchment
Causes DNA synthesis and cell division
PDGF
Growth factor + growth factor receptor
- -Receptor oligomerization
- -Receptor PTK activation
- -Phophorylation of PTK moiety
- -Docking sites form
- -Recruitment of signaling enzymes
- -Activation
Following growth factor- notes
Hemopoietic receptors membrane bound
Cytokines
- Cyclin/ CDK
- Retinoclastoma protein, Rb
- p53
- CDKI
- E2F
Regulators of cell cycle
Restriction point
Late G1
Gatekeeper of restriction point
Retinoblastoma, Rb
What happens to irreparable damage to cell
Apoptosis
Cyclin D1 expression increased
Breast cancer
Mutational inactivation of Rb genes
Retinoblastomas
Sequestration of Rb by HPV E7 protein
Cervical
Deletion of CDK1 genes, p14, p15
Many cancers
Mutant CDK4 that is resistant to CDK1 gene products, p14, p15
Melanomas
Originates from a single mutant
Tumor
Cancer causing mutant that is dominant
Protooncogene
Cancer causing mutant that is recessive
Tumor suppressor gene
Most common genetic lesion found in human cancer
p53
Type of tumor suppressor genes
Retinoblastomas
recessive
- White or red patchs
- Mouth sore that wont heal
- Bleeding
- Loose teeth
- Painful swallowing
- Lump in neck
- Earache
Signs and symptoms of oral cancer
- Smoking/tobacco use
- Heavy alcohol use
- HPV
- Chronic irritation
- Immunosuppressants
- Poor dental/oral hygiene
Risk factors for oral cancer
Gluconeogenesis and lack of uptake
Fasting hyperglycemia
Increases acetyl coA
Lipolysis
Accumulate in plasma
Ketone bodies