OPIOIDES Y

CANNABINOIDES

Rafael MALDONADO

Lab of Neuropharmacology Pompeu Fabra University

Barcelona

Cannabis sativa

Δ9-THC (Gaoni & Mechoulam, 1964) +

More than 60 Actif Compounds

CannabinoidReceptors

E

LL

M

472

1

1

360

CB1 , CB2 • Cells of the immune system

• Hippocampus • Basal Ganglia • Cerebellum • Other brain areas • Peripheral tissues

1990 1992

Δ9-Tetrahydrocannabinol O

OH1964

Cannabinoid receptor

Agonist

Β/γα* GTP

G Protein

Protein kinase A MAP kinases

Ca++ K+

The cannabinoid receptor

Endocannabinoidsareproducedondemandfromthecellmembrane

N H

O O

P O O -

O O - R 2

R 1 O

O O

C H O - R 3 O H

N H

O H O

O O

C H O H

O H

N A P E - P L D D A G L i p a s e

Phospholipid-derived precursors

Endocannabinoids

Degradation products

2-Arachidonoylglycerol Anandamide

Phospholipid remodeling

O O H

H 2 N O H H O C H O H O H

F a t t y A c i d A m i d e H y d r o l a s e M A G L i p a s e

Endocannabinoidssystemandpain

o Endocannabinoidsarereleaseinthecentralnervoussystemduringpainstates

o  Endocannabinoids inhibit the transmission andpercep9onofnocicep9ves9muli

o  CB1 and CB2 cannabinoid agonists have analgesiceffectsinmul9pleanimalmodelsandinhumans

BRAIN

BRAIN STEM

LOCUS COERULEUS

BRAIN STEM

SPINAL CORD

CORTEX

THALAMUS

HIPOTHALAMUS LIMBIC SYSTEM

SPIN

OT

HA

LA

MIC

PAT

HW

AY

PAG

N. RAPHE MAGNUS

OPIOIDS

LOCUS COERULEUS

CORTEX

THALAMUS

PAG

N. RAPHE MAGNUS

1.2 1.1

2.2

2.1

1.3

2.3

3.1

3.2

BRAIN

BRAIN STEM

BRAIN STEM

SPINAL CORD

1.  Inhibition of pain transmission

3. Change in pain perception and significance

2. Activation of the inhibitory descending pathway

HIPOTHALAMUS LIMBIC SYSTEM

SPIN

OT

HA

LA

MIC

PAT

HW

AY

CANNABINOIDS

1.  Inhibition of pain transmission

3. Change in pain perception and significance

2. Activation of the inhibitory descending pathway

LOCUS COERULEUS

CORTEX

TÁLAMO

PAG

N. RAPHE MAGNUS

1.2 1.1

2.1

2.2

3.1 BRAIN

BRAIN STEM

BRAIN STEM

SPINAL CORD

HIPOTHALAMUS LIMBIC SYSTEM

SPIN

OT

HA

LA

MIC

PAT

HW

AY

3.2

Opioids Cannabinoids

Disorientation/dizzines + +

Emesis + (antiemetic)

Constipation + -

Respiratory depression + -

Cardiovascular side effects + +

Urinary retention + -

Tolerance + (+)

Physical dependence + -

Memory impairment - +

THERAPEUTIC POTENTIAL USE

Neuropathic pain

Inflammatory pain

Opioid receptors

mu, delta & kappa

CB1

Cannabinoid receptors

CB2

THERAPEUTIC POTENTIAL USE

Neuropathic pain

Inflammatory pain

• Mostcommonformofarthri9s

• Degenera9ve,slowlyprogressingjointdisease

• Limitedefficacyofthesymptoma9ctreatment

Osteoarthri9s

Modelofosteoarthri9cpaininducedbymonosodiumiodoacetate(MIA)

• Wild-type• CB1KO• CB2KO• CB2xP(CB2over-expressioninCNS)

MIA:condrocyteglycolysisinhibitor

Mechanicalallodynia

Intra-ar9cularinjec9onofMIA

CrucialroleofCB2Rinosteoartri9spainCB1KO

CB2KO

CB2xP

Gene9callymodifiedmiceforCB1RandCB2RdevelopedsimilarhistologicalchangesaTerMIAinjec9on

Osteoarthri9cpain,emo9onalstateandcogni9vefunc9ons

Chronicosteoarthri9cpainAltera9onsoftheemo9onalstate(anxiety,depression)

(Goldenberg,2010)

Cogni9vedeficits(memory,decisionmaking)

(Hartetal,2000;DickandRashiq,2007)

RoleofCB1RandCB2Rintheemo9onalaltera9onsinducedbyMIA

1weekpostMIAinjec9on

SAL

MIACB1knockoutmice

CB2knockoutmice

%entriesinopen Totalentries%tinopenarms

%9me(s)

%entrie

s(coun

ts)

entrie

s(coun

ts)

0

10

20

30

40

50

0

5

10

15

20

25

30

0

10

20

30

40

50

0

10

20

30

40

50

%tinopenarms totalentries

WT CB1KO

%entrie

s(coun

ts)

entrie

s(coun

ts)

0

5

10

15

20

25

30

0 5

10 15 20 25 30 35

%entriesinopenarms

WT CB1KO WT CB1KO

%9me(s)

WT CB2KO WT CB2KO WT CB2KO

RoleofCB1RandCB2RinthememorydeficitinducedbyMIA

HABITUATION TRAINING TEST

Discrim

ina9

oninde

x

Discrim

ina9

oninde

x

WT CB1KO WT CB1KO-0,20

-0,10

0,00

0,10

0,20

0,30

0,40

0,50

0,60

-0,20

-0,10

0,00

0,10

0,20

0,30

0,40

0,50

0,60

CB1knockoutmice CB2knockoutmice

SAL

MIADiscrim

ina9

oninde

x

WT CB2KO-0,20

-0,10

0,00

0,10

0,20

0,30

0,40

0,50

0,60

Mechanicalallodynia

Anxiety Cogni9vedeficits

CB1KO

CB2KO

CB1KO

CB2KOCB2KO

CB1KO

Osteoartri9sMIAmodel

Evalua9onoftheendocannabinoidlevelsinthemouseosteoartrithispainmodel

Amygdala Hippocampus Prefrontalcortex

Plasma

0

4

8

12

16

20

0

4

8

12

16

20

0

4

8

12

16

20

24

0

4

8

12

16

20

24

0 4 8

12 16 20 24

0

2

4

6

8

10

nmol

/g

nmol

/g

nmol

/g

pmol

/g

pmol

/g

pmol

/g

2-AG 2-AG 2-AGAEA AEA AEA

0

10

20

30

40

50

60

0,0

0,2

0,4

0,6

0,8

ng/m

l

ng/m

l

SAL

MIA

2-AG AEA

LC/MS-MS

Roleoftheendocannabinoidsysteminosteoarthri9s:extrapola9ontohumans

Ø PainØ Anxietyanddepressivestate

Ø Cogni9on(visualmemory)

Ø Plasma9clevelsofendocannabinoids

Ø CB1RandCB2Rgeneexpressioninperipheralbloodlymphocytes

Subjects:Ø 16osteoarthri9spa9ents

Ø 14healthyvolunteers

Pain,affec9veandcogni9veparameters

inosteoarthri9spa9ents

Plasma9clevelsofendocannabinoidsinosteoarthri9spa9ents

Plasma

0

10

20

30

40

50

60

0,0

0,2

0,4

0,6

0,8

ng/m

l

ng/m

l SAL

MIA

2-AG AEA

InaccordancewithmouseMIAmodel

LC/MS-MS

CB1RandCB2Rgeneexpressioninperipherallymphocytes

VacutainerCPTtube(NC:1ml,Ficoll:2ml)

Bloodsample+HumanTotalLymphocyte

EnrichmentCocktail

Healthyvolunteers Osteoarthri9spa9ents

Correla9onsbetweenplasma9clevelsof2-AGandosteoarthri9sparameters

Conclusions

ü  Theendocannabinoidsystem is involved in thephysiopathological processes leading to pain andemo9ona l a l t e r a9ons a s soc i a t ed w i thosteoarthri9s

ü  The endocannabinoid system represents ap o t e n 9 a l b i om a r k e r a n d i n t e r e s 9 n gpharmacological target for therapeu9c purposesinosteoarthri9spain

Acknowledgements

JorgeManzanares

FranciscoNavarrete

RafaelMaldonado

CarmenLaPorta

AndreeaBura

RafaelDeLaTorre

AntoniPastor

JordiMonfort

JoneLlorente