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Flashcards in Antiinflammatory Steroids Deck (38)
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1
Q

Drug list

A

Aldosterone

Cortisol

Prednisolone

Dexamethasone

Fludrocortisone

2
Q

Mineralocorticoid role?

A

water, electrolyte balance

3
Q

Glucocorticoid role?

A

Primary effects on carbohydrate and protein metabolism ***Antiinflammatory effects

4
Q

Corticosteroid comparisons

A

Everything is compared to cortisol.

Cortisol and Cortison have shortest DOA.

Betamethasone and Dexamethasone have longest DOA.

** Fludrocortisone is the mineralocorticoid of choice for replacement therapy.

5
Q

Regulation of synthesis of CORTISOL

A

Stimuli (NT) >>

Hypothalamus to release CRH (via neurons)

>> Anterior pituitary to release ACTH (via blood)

>> Adrenal cortex: stimulates cholesterol and increased synthesis and release of CORTISOL

Cortisol >> negative feedback IMMUNE SYS (cytokines stimulate CRH and ACTH), negative feedback on CRH and ACTH)

6
Q

Diurnal Variation

A

Cortisol

Hi in morning
Lo in evening

NOTE: very small relative aldosterone levels

7
Q

Actions of Glucocorticoids

A

Maintains blood glucose

  • increase liver synthesis
  • increase protein breakdown (donate carbons)
8
Q

Actions of Glucocorticoids

A

Lipid metabolism

  • permissive effects to facilitate other hormones (epi, growth hormone)
  • increase free fatty acids
9
Q

Actions of Glucocorticoids

A

CV Adverse effects
- HTN with prolonged high levels (more than Na retention)

Skeletal Muscle Adverse effects
- muscle wasting, especially in the limbs (fast-twitch go first)

10
Q

Actions of Glucocorticoids

A

CNS
- excess or insufficiency, mood alterations, insomnia, euphoria, restlessness, increased motor activity OR anxiety, depression, psychosis

11
Q

What is the major use for Glucocorticoids?

A

Antiinflammatory action (occurs at higher doses)

STEROIDS DO NOT PREVENT OR SUPPRESS THE UNDERLYING DISEASE PROCESS THAT RESULTs IN INFLAMMATION but they can suppress the inflammation associated with multiple inciting events.

*but can be life saving!!

12
Q

Glucocorticoid Anti-inflammatory MOA

A

Alter immune responses of lymphocytes

Alter cytokine release and synthesis- macrophages and monocytes

Decrease production of prostglandin/leukotriene products

13
Q

Where are the nuclear receptors for glucocorticoids?

A

Class 1 NR = CYTOPLASM

Class 2 NR = NUCLEUS

14
Q

What is the MOA for glucocorticoids?

A

The GC receptor resides in the cytosol and has Zn finger binding domains.
Induces expression of new proteins
- lipocortin
- IkB

Transpression: alters interactions with other proteins and transcription factors . . . INHIBITS PROTEIN expression.​​

15
Q

Why does the mineralocorticoid receptor bind cortisol with high affinity?

A

There is an enzyme that inactivates cortisol to cortisone to prevent excessive stimulation of the MC receptor.

Note: aldosterone does NOT stimulate the GC receptor

16
Q

How does licorice cause HTN?

A

Licorice inhibits 11-beta HSD2, which is the enzyme that prevents cortisol from stimulating MC receptors too much.

17
Q

How does Cortisol regulate stress?

A

Cortisol-ACTS as a BRAKE ON THE IMMUNE SYSTEM
Helps to protect against life threatening consequences of a full blown inflammatory response in stress.

**recall the relase of inflammatory cytokines

18
Q

What should you do when a patient on replacement cortisol is under stress?

A

give EXTRA cortisol

19
Q

What are four ways to inhibit inflammatory events via the GC receptor?

A

Key: the antiinflammatory effects and the immunosuppressive effects of GCs are linked

20
Q

How does cortisol inhibit the Arachidonic acid pathway?

A
  1. Induces synthesis of Annexin 1.
  2. Annexin inhibits phospholipase A2

Recall . . . PLA2 promotes synthesis of arachadonic acid which makes prostaglandins and leukotrienes.

21
Q

Where do steroids work on the AA pathway?

A

high up

22
Q

How to GCs affect the cyclooxygenase pathway?

A

Cox 2 is the isoenzyme that is induced under inflammatory conditions.

Glucocorticoids inhibit the synthesis of Cox-2 such that prostaglandin metabolite production is decreased.

23
Q

What are the effects of GCs on components of the immune response?

A

EVERYTHING goes DOWN.

24
Q

What does TNF alpha do?

A

**central **role in inducing inflammation.

Produced by: macrophages, lymphocytes, NK cells

*Increases *

  • epithelial permeability
  • proteinases
  • chemokines
  • IFN gamma
  • NFkB
25
Q

How do GCs decrease TNF alpha?

A

By decreasing NFkB activation.

NFkB usually stimulates TNF alpha production in nucleus.
GC increases **IkB **expression which binds up NFkB.

26
Q

GC absorption

A

Oral
IV
IM

Topical (if skin abraded and broken)

27
Q

GC metabolism

A

Liver and Bile

28
Q

GC Excretion

A

inactive metabolites excreted in urine

29
Q

Cortisol 1/2 life

A

60-90 min

30
Q

When do toxicities occur with GCs?

A
  1. cessation of therapy (abrupt withdrawal, usually > 1wk tx)
    d/t suppression of HPA axis >> results in adrenal insufficiency
  2. high dose for inflammation
    = mimics cushing’s syndrome
31
Q

How long does recovery take after withdrawal of GC therapy?

A

Rapid withdrawal precipitates symptoms- fever, myalgias, arthralgis, malaise

Recovery usually takes several weeks to months—may take years

Recovery accomplished by slowly tapering the dose

32
Q

the “hyper” toxicities

A

HTN, hyperglycemia

Increased susceptibility to infection

33
Q

the “o” toxicities

A
  • osteoporosis (inhibits osteoblasts)
  • osteonecrosis (will need joint replacement)
  • optic: cataracts **especially kids!!!
34
Q

other toxicities

A
  • grown suppression (children)
  • peptic ulcer disease
  • cushing’s syndrome (fat redistribution, striae, acne, hirsutism)
  • behavioral disturbances
  • myopathies
35
Q

Diagnostic application of GCs

A

dexamethasone used to diagnose hypercorticism

36
Q

Therapeutic principles

A

A single dose of GCs is without harm.

**Short course **of tx (up to 1 wk) unlikely to be harmful.

37
Q

Duration of therapy

A

As the duration of therapy increases, time and dose-related increases in the incidence of adverse effects occur (can be lethal or disabling).

_Use the lowest dose possible to achieve the desired result _

38
Q
A