Introduction to pharmacology

Question 1

How do animals recognise and treat illness?

Answer 1

Some animals are known to only eat certain plants when sick. E.g A dog eats grass to vomit, chimp eats Vernonia amygdalina

Question 2

What is pica?

Answer 2

A craving for non- nutritious food due to mineral deficiencies. Seen in pregnancy

Question 3

Outline the history of pharmacology.

Answer 3

Seen in primitive societies where the use of medicinal plants were restricted to holy men. E.g. in Chinese traditional medicine, ma Huang was used which is where ephedrine is derived, or Hippocrates’ use of willow back for fever (aspirin) . Some of the oldest medical tests date back to 1500 BC. Major failure was lack of understanding of nature of disease.

Question 4

Discuss the use of herbal medicine today and homeopathy.

Answer 4

• Many people believe herbal medicines are safer because they’re ‘natural’.
• Homeopathy is a medical system based on the belief that the body can cure itself.

Question 5

What are the limitations of herbal medicine?

Answer 5

• Many substances are present, increasing likelihood of toxicity
• Quantity of active ingredient present unknown

Question 6

What is a drug?

Answer 6

• Substances that have beneficial biological activity.
• This includes herbal medicine that have biological activity.

Question 7

Discuss the differences between chemistry based and target led discoveries.

Answer 7

• Chemistry: select chemical, screen for biological activity, mechanism usually unknown / effect known.
• Target led: choose drug target (protein), screen chemical for binding target, mechanism known and effect predicted.

Question 8

What are monoclonal antibodies?

Answer 8

• An antibody produced by a single clone of cells or cell line and consisting of identical antibody molecules.

Question 9

What are the advantages of MOABs?

Answer 9

• Bind to a single epitope on a single antigen.
• Have a single type of antibody.
• Animals not needed for production.
• Large amounts can be made.
• Predictable properties.

Question 10

Disadvantages of MOABs?

Answer 10

• Expensive to make
• Antigenic leads to HAMA (human-anti-mouse antibodies)
• Have to be given IV

Question 11

How are nucleic acids used as drugs?

Answer 11

• Capable of targeting a disease at the genetic level by preventing the expression of disease-causing proteins. E.g. antisense molecules.

Question 12

Discuss RNA based therapeutics.

Answer 12

• The use of coding RNA such as mRNA as well as non-coding RNAs such as small interfering RNAs to target proteins and DNA.

Question 13

Discuss gene therapy.

Answer 13

• The treatment of diseases caused by in-expression of protein due to genetic mutation or the suppression of a gene due to pharmacological process.
• E.g Alipogene tiparvovec is used for lipoprotein lipase deficiency (withdrawn for poor sales) or Strimvelis to treat adenosine deaminase deficiency (SCID).

Question 14

Discuss cell based therapies.

Answer 14

• Modifying a patient’s own cells or cells from a donor to fight disease and alleviate medical conditions.
• E.g stem cells used to replace destroyed immune cels post chemo.

Question 15

What are the 2 types of stem cells and give an example.

Answer 15

• Embryonic: can differentiate into any cell.
• Adult: can only differentiate into cells from their tissue of origin.
• E.g Holocar replaces the damaged stem cells in disorders such as Limbal stem cell deficiency.

Question 16

Discuss Chimeric antigen receptor T-cell (CAR-T) therapy.

Answer 16

• T-cells are harvested from the patient (autologous) or a donor (heterologous) and engineered to recognise the tumour cell and infused into patient.
• It’s a combination of cell based and gene therapy.

Question 17

Discuss treatment strategies.

Answer 17

1. Defective/absent protein:
   - Use recombinant protein
   - Use drug to mimic protein
   - Replace defective gene
2. Defective/absent cell
   - Necessary to replace cell (stem cells)