biomarkers and drug targets

Question 1

identify the leading causes of death

Answer 1

ischaemic heart disease, stroke, COPD, lower respiratory infections, neonatal conditions, trachea bronchus lung cancers, alzheimers and dementia, diarrhoeal diseases

Question 2

define the term biomarker

Answer 2

measurable characteristics that are indicators of physiological/pathological processes.
ex: glycosylated proteins in diabetes, estrogen receptor expression in breast cancer

Question 3

identify how drug efficacy can be monitored in vivo

Answer 3

Imaging techniques: MRI, CT, PET (visualizes the effect of a drug on the body)

Biomarkers: blood glucose levels, blood pressure, cholesterol levels, (assesed before and after treatment to determine effectiveness)

Clinical endpoints: measurable outcomes that reflect the effect of a drug on the patient’s health. (survival, disease progression, quality of life, and symptom relief)

PK studies: studies can help determine the optimal dose and dosing schedule for a drug, which can improve efficacy.

Animal models.

Question 4

identify non-specific and specific targets of drug action

Answer 4

non-specific targets: are small molecules dependent on drug biodistribution. (just interaction no molecular target)
ex: lactulose, osmotic laxative for constipation
mannitol: osmotic diuretic
sodium thiosulphate: combines with cyanide for poisoning
potassium permanganate: antiseptic oxidising agent
ferrous sulphate: anemia
magnesium carbonate & sodium bicarbonate: neutralizes stomach acid
desferrioxamine: chelates iron to make it unabsorbed in gut
cenodeoxycholic acid: dissolves aggregated cholestrol in gall bladder (bile acid)

specific targets: macromolecules (has a target) partly dependent on drug biodistribution

Question 5

define four major families of drug targets (give examples of ones that cross boundaries between families)

Answer 5

1. receptors
2. ion channels
3. transporters
4. enzymes

catalytic receptors, receptor outside enzyme inside
chanzymes, ion channels with enzyme function
transporters with ion channel like function, ion channel passive transporter active (glut uptake with cl-ions EAAT4/5)

Question 6

describe how primary, secondary, tertiary and quaternary structures of proteins are defined and represented

Answer 6

primary: sequence of AA in polypeptide chain (determined from DNA seq). represented as 1-3 letter code for each AA.

secondary: folding patterns of polypeptide chain (alpha helices: spiral structures formed by hydrogen bonds between AA and beta sheets: flat, sheet-like structures formed by hydrogen bonds between adjacent strands)

tertiary: overall 3d shape determined by interactions between regions of the amino acid chain, including hydrogen bonds, disulfide bonds, hydrophobic interactions, and electrostatic interactions. represented as a space-filling or ribbon diagram.

quaternary: structure in complex with other proteins. determined same as tertiary.