Prostaglandins as Drugs Synthesis scheme of , their main actions and action site of drugs

Cox 1-2

Recettori (cAMP, DAG, IP3)

Topical F2 alpha in the treatment of open-angle glaucoma, a progressive disease of the optic nerve, represents an important cause of blindness worldwide. One of the risk factors is the increased intraocular pressure (IOP), consequent to an "accumulation" of aqueous humor inside the anterior and posterior chambers of the eye, although glaucoma can also occur in people with intraocular pressure in the range of normality (12-21mmHg; the so-called normal pressure glaucoma. The most frequent type of glaucoma (60-70% of cases) is the open-angle type, in which the accumulation of aqueous humor is consequent to a reduced flow through the drainage system of the ocular chamber. Lowering the IOP can reduce the risk of damage to the optic nerve and preserve the visual field, regardless of whether the IOP is increased or not. Furthermore, the earlier and more consistent the reduction of IOP the better the prognosis Reduction of intraocular pressure in glaucoma open angle in ocular hypertension

travoprost

Side effects (pigmentation, dryness, conjunctivitis)

Prostaglandins for ophthalmic use: latanoprost, bimatoprost, travoprost (F2-alpha) Latanoprost (Xalatan, Pharmacia Upjohn), bimatoprost (Lumigan, Allergan) and travoprost (Travatan, Alcon) are chemically related to F2alfa. They probably act by increasing the elimination of aqueous humor by the uveoscleral route.

Clinical use of

Abortive

Gastrointestinal

Cardiovascular Synthesis scheme of eicosanoids, their main actions and action site of drugs

Cox 1-2

Recettori (cAMP, DAG, IP3) antiprogestogen

Abortive

Mifepristone = antiprogestogen synthetic steroid, binds progesterone

Clinical utilization of Prostanoids

Gastrointestinal: (prevent ulcer)

Cardiovascular: alprostadil PGE (maintaining patency of the ductus arteriosus in neonates with malformations)

Epoprostenol instead of heparin (eg renal dialysis) DRUGS FOR RHEUMATOID ARTHRITIS Osteoarthritis: chronic pathology of the articular cartilage, with secondary involvement of bone, synovium, capsule. Elderly subjects, female. Hip, knee, vertebrae are more susceptible

Rheumatoid arthritis: chronic and progressive inflammatory polyarthritis with autoimmune pathogenesis of the synovial joints. It initially affects the synovial membrane and not the cartilage. Less frequent, younger age than osteoarthritis, women more affected (3: 1 ratio) * NSAIDs of larger utilization in rheumatic diseases

B = short < 3 ore M = medium 4-8 ore L = long > 8 ore

Choice of NSAID Rheumatoid arthritis

(drugs that modify disease course) Rheumatoid arthritis: chronic and progressive inflammatory polyarthritis with autoimmune pathogenesis of the synovial joints. It initially affects the synovial membrane and not the cartilage. Less frequent, younger age than osteoarthritis, women more affected (3: 1 ratio) . (TNF) . (IL1) * . (TNF)

. (TNF)

* Mechanism of action of metotrexate

Decreases coenzymes having folate base

FH 4 = tetrahydrofolic acid

Active metabolite 7-hydroxymethotrexate, half-life 7 h, liver toxicity Mechanism of action of leflunomide

Blokade of autoimmune lymphocytes

Pro-drug Active metabolite malononitrilamide (A771726), half-time 15-18d Other therapies

•Chloroquine = antimalarial has anti-inflammatory effects (lysosome pH, APC, TollR)

•D-penicillamine = analogue of cysteine; slows progression; side effects: nephritis, aplastic anemia, used only when other treatments do not work

•Gold salts = prevent damage, toxic effects. They are picked up by macrophages and suppress phagocytosis and lysosomal activity Toll-like Receptors Theraphy Cytokines Cytokines

IL-1b and TNF-alpha secreted by synovial macrophages proliferate synovial cells and synthesize collagenase which degrades cartilage . (TNF) . (IL1) -

. (TNF) -

. (TNF)

- Theraphy Cytokines

Etanercept (recombinant protein) (TNF-alpha, beta)

Adalimumab (antibody), infliximab (antibody) (TNF-alpha)

Anakinra (IL-1 receptor)

AUTACOIDS (self-care)

Eicosanoids

Platelet Activating Factor (PAF)

Histamine

Bradykinin

5-HT Activating Factor PAF Platelet-activating factor (inflammation and asthma)

SYNTHESIS and DEGRADATION

STRUCTURE *

PAFR PAF Functions

Angiogenesis (stimulates through VEGF) Apoptosis (pro and anti) Skin (morphogenesis and proliferation) Immune and inflammatory response (mediation of interactions between endothelial cells and leukocytes) Asthma (bronchoconstriction, mucus secretion) Diabetes (development of type I diabetes, insulitis) Renal disorders (nephropathy) Vascular disorders (aortic aneurysm, stroke, atherosclerosis) Reproduction and delivery (ovum implant, embryo development) Gout Drugs Risk factors associated with increased urate:

Age Gender Meat, seafood, beer, liqueurs (foods with high purine content) Diabetes, hyperlipidemia, hypertension, obesity

Drugs: (low doses), diuretics, anti-rejection in organ transplants Deposition of urate microcrystals in: Joints Extra-articular Tissues Renal tubules Subcutaneous tissue

Gout arthritis Tophi Biosynthesis and biotransformation processes of uric acid Role of Uric Acid in inflammation

Kydney and joints 1

3

2 Mechanisms for decreasing Uric Acid: Interference with synthesis of UA Inhibition of leukocyte entry in the joint UA increase Decreased re-absorption of UA

, Benziodarone Processi di biosintesi e di biotrasformazione dell’acido urico Allopurinole, Colchicine Role of Uric Acid in inflammation

Kydney, joints Side effects of colchicine Probenecid, benziodarone, sulfinpirazone Uricosuric drugs

Sulfinpirazone 1 filtration

2 riassorbimentoRiassorbi Probenecid (an mento organic acid). OAT binds preferentially to it instead of uric acid, 3 secretion + preventing its distal reabsorption and increasing excretion

4 Riassorbi mento

ASA competes with UA Benziodarone reduces effect of probenecid INTERACTION WITH OTHER DRUGS

Low/medium doses (1-2 g)