Topic 5: Endocrine System & Phytomedicines

Question 1

Progesterone

Answer 1

precursor to other steroid hormones including androgens, estrogens, and glucocorticoids

produced by the corpus luteum and the placenta

Question 2

Uses of Progesterone

Answer 2

female contraceptives
prevent spontaneous abortion
treat menstrual disorders

Question 3

Estrogens

Answer 3

-substance that exerts agonistic biological effects on he estrogenic receptors

Question 4

Sources of endogenous estrogens

Answer 4

• ovaries, testes and placenta
• estradiol (E2) is more potent endogenous human estrogen
• estrone (E1) is a weaker estrogen formed in fat cells

Question 5

Effects of Estrogen

Answer 5

• stimulate growth and maturation of long bones
• stimulate secondary sexual characteristics
• influence course and length of menstrual cycle

Question 6

Uses of Estrogens

Answer 6

• female contraceptives
• menstrual disorders
• menopausal symptoms
• osteoporosis in post-menopausal women
• estrogen deficiency

Question 7

Androgens

Answer 7

• agents that stimulates the development of male sex characteristics
• testosterone is an androgen
• androsterone is a testosterone metabolite (found in male urine)

Question 8

Sources of Endogenous Androgens

Answer 8

• interstitial cells of testes

- ovary

Question 9

Androgen Therapeutic Uses

Answer 9

• cryptochism (non-descended testes)
• hypogonadism (inadequate gonadal function in males)
• menorrhagia (excessively prolonged or heavy menses)
• testosterone deficiency

Question 10

Glucocorticoid Sources

Answer 10

• adrenal cortex

- adrenal glands secrete cortisol- the most potent endogenous glucocorticoid

Question 11

Uses of Glucocorticoid

Answer 11

• anti inflammatory
• immunosuppressant
• treatment of cortisol deficiency

Question 12

Glucocorticoids (molecules)

Answer 12

• hydrocortisone
• cortisone
• prednisone
• prednisolone
• methylpredisolone

Question 13

Glucocorticoid Mechanism of Action

Answer 13

Down regulates cytokine production which reduces inflammation: Steroid binding of glucocorticoid receptor (GR) in cell cytoplasm results in activation of receptor and translocation to the nucleus where regulatory region of certain genes are effected including negative regulation for genes that code for a number of cytokines.

Also reduces protaglandin production which reduces inflammation: Blocks conversion of phospholipid to arachidonic acid which blocks the formation of prostaglandins

Question 14

Immunosuppressant Uses of Glucocorticoids

Answer 14

oral administration:

• systemic lupus erythematous
• idiopathic thrombocytopenis purpurea

Question 15

Replacement Therapy for Glucocorticoid Deficiency

Answer 15

Oral administration:

• congenital adrenal hyperplasia
• panhypopituitarism

Question 16

Dioscorea Mexicana

Answer 16

Source of diosgenin
Common Name: wild yam
Geography: Mexico
Habit: Herbaceous climber
Plant part Used: rhizomes
Ethnomedical Uses: anti inflammatory, fish poisons, etc.

Question 17

Diosgenin

Answer 17

Steroid
Use in modern medicine (derivatives included):
- female contraceptive (progesterone & estrogen)
-anti inflammatories & immunosuppressants (glucocorticoids)
-horomone replacement for estrogen, androgen, or cortisol deficiency

Question 18

Diosgenin Chemical Derivatives

Answer 18

progesterone, which is then synthesized into:

• estrogen
• androgens
• glucocorticoids

Question 19

Female Contraceptives

Answer 19

Progesterone (main component) & estrogen for oral contraceptives .
Progesterone prevents the estrogen surge which blocks the release of gonadotropin releasing hormone (GnRH) from the hypothalamus which inhibits the mid cycle gonadotropin surge of FSH (follicular stimulating hormone) and LH (lutenizing horomone) produced by the pituitary gland.
-cervical mucus becomes thick and viscid
-endometrial changes make it more difficult for implantation

Question 20

Progestin/progestogen & estrogen Contraceptives

Answer 20

• started when menstruation is over
• taken for 21 days, followed by 7 days off
• reduce risk of ovarian cancer
• reduce risk of breast cancer when taken for less than 10 years

Question 21

Male Contraceptive:

Gossypium spp. (cotton)

Answer 21

Common Name: cotton
Geography: China
Plant part Used:oil from fruit
Ethnomedical Uses: birth control on males
Active compound: gossypol

Question 22

Gossypol mechanism of action

Answer 22

inhibits sperm formation

Question 23

Hevea brasiliensis (para rubber)

Answer 23

Geography: S. America, rainforest
Plant part used: bark latex
Ethnomedical use: utensils
Mech of action: mechanical protection

Question 24

Benign Prostatic Hypertrophy

Answer 24

-Elevated levels of dihydrotestosterone (DHT) in prostate

-

Question 25

Dihydrotestosterone (DHT)

Answer 25

- potent form of testosterone that stimulates the enlargement of the prostate cells - testosterone is converted to more potent DHT by 5-alpha- reductase

Question 26

5-alpha-reductase (5AR)

Answer 26

converts testosterone into DHT. | activity increases with age and its main action is on the prostate

Question 27

Serenoa repens

Answer 27

Common Name: Saw palmetto Geography: Native to Florida Ethnomedical Use: fruits used by Native Americans to treat benign prostatic hypertrophy, is an aphrodisiac

Question 28

Saw Palmetto Mechanism

Answer 28

Inhibits 5-alpha reductase and in turn production of DHT in the prostate

Question 29

Vitex agnus-castus (Chasteberry)

Answer 29

Common Name: chasteberry Geography: S. Europe Ethnomedical Use: reduces sexual desire and premenstrual stress syndrome.

Question 30

Chasteberry Mechanism

Answer 30

stimulation of gondadotropin releasing horomone in hypothalamus --> increases release of LH increases progesterone level decreases estrogen

Question 31

Oenothera biennis

Answer 31

Common Name: Evening primrose Geography: Europe Ethnomedical Use: oil from ripe seeds & aerial parts used to treat premenstrual syndrome, menopausal hot flashes

Question 32

Cimicifuga (actaea) racemosa

Answer 32

Common Name: black cohosh Geography: Eastern North America Ethnomedical Use: roots and rhizomes used for PMS, and menopausal hot flashes.

Question 33

Ginseng Panax ginseng & P. quinquefolius

Answer 33

Common Name: ginseng Geography: Panax- Koreas, NE China P. quinquefolius- E. North America Ethnomedical Use: tonic to enhance mood, physical performance, intellectual performance, improve metabolic functions, aphrodisiac

Question 34

Galactogogues

Answer 34

enhance flow of breast milk

Question 35

Tigonella foenum-graecum (fenugreek)

Answer 35

Common Name: fenugreek Geography:Europe Ethnomedical Use: galactogogue, used in tea, Eurasian condiment

Question 36

Saponaria officinalis

Answer 36

Common Name: soapwort Geography:Europe Ethnomedical Use: galactogogue