Exam 3- Medical Botany USF

Taxus Alkaloids

Taxaceae

Taxus spp.

yew- common ornamental shrub/tree

non-flowering conifer

Taxus baccata (Yew)

Taxine B

Found in plant parts- leaves and seeds

red aril edible

Taxus baccata (Yew)- Chemical side

antagonist calcium and sodium channels

cause hypertension, cardiac arrest, death

Taxus baccata (Yew)- drug interactions

ANTI-Cancer agents, work in relatively low dose, semisynthetic approach

Yew

slow growing, all parts toxic except aril (even after drying)

Juniper

Female seed cone produced by tree; cone contains spice --> derived from conifers

Paclitaxel

Taxus spp.

binds tublin --> prevents breakdown, induced apoptosis (cell death), used in combo with other drugs

Docetaxel

Semi-synthetic analogue

Cardiac Glycosides

Apocyanaceae, Plantaginaceae, Asparagaceae, Ranunculaceae

Two types of Cardiac Glycosides

Cardenolide and Bufadienolide

Glycosides

Compounds formed from sugars and other molecules.

glycosidic bond

bond between sugar and aglycone

sugar= usually carbon ring(s) with many hydroxyl groups

Aglycone

Non-sugar component of glycosides.

Mechanism of Cardiac glycosides

1) Increased intracellular Na+ concentration 2) Decreased Na+ Electrochemical gradient 3) Decreased Na/Ca antiporter activity 4) Increased intracellular Ca2+ concentration (tropain) --> causes intense and irregular contractions or death

Apocynaceae (Dogbane Family)

5000 spp., some produce cardioactive steroids / some produce monoterpene indole alkaloids with nervous system effects

Strophanthus kombe

Apocynaceae, arrow kills an elephant

Plantaginaceae family

Digitalis lanata (foxglove family)

Digoxin

Plantaginaceae family, used in systolic heart failure --> increase cardiac input --> reduce hospitalization

Oubain

increases cardiac output, less readily absorbed by the GI tract, rapidly eliminated

Nerium oleander

Apocynaceae

Nerium oleander toxicity

Caused by presence of cardiac glycosides

every part toxic

fumes are toxic and are not used to skewer

Adonis spp (Pheasant's eye)

Ranunculaceae

So toxic it can even kill horses that eat it

Convallaria majalis (lily of the valley)

Asparagaceae family

Contains convallotoxin cardiac glycoside

Catha edulis

Celastraceae

chewed in prohibition

Three types of muscle

skeletal, cardiac, smooth

Skeletal muscle

striated and voluntary

Smooth muscle

under automatic nervous system and hormone from blood

- GI

-Blood vessels

-bladder

-airway

-uterus

-eyes

Cardiac muscles

Heart (autonomous activity but also influenced by automatic nervous system)

Acetylcholine

Cholinergic agonist

Paralyzing curares

Menispermaceae

Loganiaceae

Fabaceae

Menispermaceae

Chondrodendron tomentosum

Tubocurarine

Naturally occurring nicotinic receptor antagonist from Chondrodendron tomentosum

tubocurarine mechanism of action

inhibits the action of acetylcholine and blocks neural transmission without depolarizing the post-synaptic membrane

Loganiaceae

strychnos spp.

paralyzing curare: Toxiferine

Toxiferine

paralyzing curare

Strychnine

glycine antagonist

spasm and convulsions

Glycine receptor antagonist

Strychnine, glycine agonizes chloride channel- hyperpolarization

Erythrina spp.

Fabaceae

orally effective

antagonist of nicotinic acetylcholine

Erythrina herbacea

Coral Bean (Fabaceae)

used in rat poison

Piperidine alkaloids

Solanaceae

Apiaceae

Piperidine alkaloids- Solanaceae

Nicotiana spp.

Nicotine effects on body

In muscle

Tremor and Pains

Conium maculatum

poison hemlock

Apiaceae

Coiine (Conium)

Piperidine alkaloid

most toxic alkaloid

Coiine mechanism

Antagonist of nicotinic acetylcholine receptors --> nAChR involved in muscle stimulation

Mushroom toxins that cause cell destruction, liver and kidney damage, death

Cyclopeptides

MMH

Orallenine

Mushroom toxins that cause cell destruction, liver and kidney damage, death symptoms

occur after ingestion over 6 hours can take weeks

Cyclopeptides

Amanita, Galerina, Lepiota, (6-10 hr)

MMH (gyromitrin)

Gyromitra

Helvella

Sarcospheara (6-10 hr)

Orallenine

Cortinarius orellanus (as long as several weeks)

Mushrooms that affect AUTOMATIC Nervous system

Corprine

Muscarine

Mushrooms that affect AUTOMATIC Nervous system symptoms

occur within 20 mins to 2 hrs

Corpine

antabase-like

Corpinus (inky cap)

Muscarine

Clitocybe

Inocybe

Mushrooms that affect CENTRAL nervous system symptoms

occur within 20 mins to 2 hrs

Mushrooms that affect CENTRAL nervous system

Ibotenic acid- muscimol

Psilocybin, Psilocin

Ibotenic acid and muscimol

Amanita muscaria

psilocybin and psilocin

psilocybin and paneolous

Mushrooms that cause GI irritation

Agaricus, Amanita, Boletus, Chlorophyllum

Mushrooms that cause GI irritation symptoms

30 mins to 3hrs

Different types of Mushrooms and structure identification

Spore prints

Features of Giltrama

Type of Hymenium

Features of cystidia etc.

Cap

Pileus

Scale

remnants of the universal veil

Gills

lamellae (on surface bearing basidia / hymenium)

Ring

annulus

Volva

cup

Gils structure

Dense or Sparse

Corpinus atramentarius

Corpine

Inky caps

Inhibits aldehyde dehydrogenase

Corpinus atramentarius reaction

facial flushing, headache, nausea, vomiting, tachycardia

Clitocybe

contains muscarine (parasympathetic agent)

Inocybe

mushrooms that can cause muscarinic cholinergic toxicity

PSL syndrome

Caused by Muscarine toxins

perspiration, salivation and lachrymation. Latent period of 30 minutes up to six hours before symptoms appear.

ibotenic acid

Amanita

Panaeolous

Conocybe

Gymnopilus

Amanita muscaria

known as agarin or pantherine

psychoactive constituents

acts as a GABA agonist

Amanita muscaria symptoms

Sedative, Hallucinations, delirium

psilocybin and psilocin overview

psilocybin is quickly converted by the body to psilocin

-Mind-altering effects such as LSD, mescaline, and DMT

-changes in perception, euphoria, hallucinations

Amanitins

Amanitins (cyclopeptides)

Amanita bisporigera

Amanita bisporigera

produces amanitin that inhibits transcription

puffball mushrooms are confused with the button stages of Amanita

Gyromitrin

Monomethyl hydrazine acts on the central nervous system

match to MMH

depletes CNS pyridoxine (vitamin B6)

reduces GABA synthesis

Orellanine poisoning

symptoms may not show up for 8 days

nausea, vomiting, stomach pains, headaches, and muscle aches

Psychedelics

Substances causing altered states of consciousness; are shown to reopen critical periods of brain development.

Psychedelic Characteristics

changes in perception, mood, and cognitive processes

Critical periods

-windows in which the brain can respond to the response of the nervous system to environmental stimulation.

- allows new skills and behaviors to be learned

-once closed cannot reopen

Psychedelics as treatment

-act as a master key, can reopen critical periods

-induces a state of neural plasticity --> re-learning of social behaviors

- used in stroke, autism, and PTSD

Sumerian clay tablet (5000 year old)

12 recipes: 250 various plants --> like alkaloid plants (poppy), kenbane, mandrake

Oldest documentation

Pen T'sao (2500 BC)

365 drugs ( dried )- camphor, Rhei rhisoma, Thea folium, jimson weed, cinnamon bark, etc

Homer's Iliad and the Odyssey (abt 800 BC)

63 plants from Minoan, Mycenaean, and Egyptian pharmacotherapy

Mythological folklore naming

Indian book Vedas

treatment with plants native to India: nutmeg, pepper, clove

now used as spices

Ebers Papyrus (1500 BC)

800 proscriptions of 700 plants used for therapy: pomegranate castor oil, aloe, garlic, onion, etc.

De succedanus- Galen (131 AD-200)

First list of parallel drugs

introduced new drugs in therapy

Parallel drugs

drugs that similar or identical actions

Conium maculatum

poison hemlock

Conium maculatum prominent toxins

Coniine and y-coniceine --> Piperidine alkaloids

Coniine and y-coniceine

overt toxicity in humans and animals and shown to cause birth defect

- shown to cause cleft palate in goats

Coniine and y-coniceine chemical aspect

Most symptoms appear at the neuromuscular junction

Action at the automatic ganglia --> toxins produce biphasic nicotinic

Antagonist of nicotinic acetylcholine receptor

Symptoms of coniine (piperidine alkaloids)

salvation, mydriasis (pupil dilation), tachycardia (fast heart rate), then bradycardia (slow heart rate)

seen in a boy who ate a wild carrot top

Cure of coniine poisoning

no antidote but supportive treatment can be used

- Resp. support and GI decontamination (pumped stomach)

-Anti-convulsants

-Forced diuresis (forced pee) can prevent renal failure

Is ingestion of poison hemlock common?

NO

-"mousy" odor

-bitter taste

-burning of mouth and throat