Dipartimento di Neuroscienze Università degli Studi di Torino

Dipartimento di Neuroscienze Università degli Studi di Torino e Istituto Nazionale di Neuroscienze Torino www. personalweb. unito. it / fabrizio. benedetti

Therapeutic Negative effects

Placebo (inert treatment) Symptom reduction spontaneous remission others regression to the mean conditioning cognitive factors

Placebo effect = Context effect Dummy treatment Medical treatment

Conscious Unconscious Conditioned response COGNITION • Expectation • Belief • Trust • Hope Effect Conditioned stimulus Unconditioned stimulus (e. g. drug)

DISEASE/SYSTEM TREATMENT MECHANISM ________________________________________________ Pain Placebo administration Expectation-induced activation of Nocebo administration endogenous opioids and cholecystokinin Verbal suggestions as well as of several brain regions Open vs hidden administration ________________________________________________ Parkinson’s Placebo administration Expectation-induced release of dopamine Disease Nocebo administration in the striatum and changes of firing Verbal suggestions pattern of subthalamic nucleus neurons Open vs hidden administration ________________________________________________ Depression Placebo administration Changes of metabolic responses in different brain regions (inhibition of 5 -HT re-uptake? ) ________________________________________________ Anxiety Placebo administration Change of activity of some brain regions Open vs hidden diazepam ________________________________________________ Addiction Expected vs unexpected Changes of metabolic activity in methylphenidate different brain regions ________________________________________________ Autonomic responses to DBS Open vs hidden DBS Change of neuronal excitability in limbic areas ________________________________________________ Cardiovascular Placebo administration Reduction of b-adrenergic activity of heart ________________________________________________ Respiratory Pharmacological pre-conditioning Conditioning of opioid receptors in with buprenorphine the respiratory centers ________________________________________________ Immune Pharmacological pre-conditioning Conditioning of some immune mediators system with immunosuppressive drugs (e. g. , IL-2, IFN-g, lymphocytes) ________________________________________________ Endocrine Pharmacological pre-conditioning Conditioning of some hormones system with 5 -HT 1 B-1 D receptor agonists (e. g. , growth hormone, cortisol)

Colloca and Benedetti (2005) Nature Rev. Neurosci. 6: 545 -552

Pain tolerance (minutes) 30 25 Experimental ischemic arm pain 20 Morphine m opioid receptors 15 Naloxone 0. 4 mg-------- 10 mg m d k DAY 1 DAY 2 DAY 3 DAY 4 MOR PLA NAL 10 mg Amanzio & Benedetti (1999) J. Neurosci. 19: 484 -94 DAY 5

Carfentanil m-opioid receptor radiotracer Zubieta et al. (2005) J. Neurosci. 25: 7754 – 7762

Remifentanil m-opioid receptor agonist Placebo Par ACC PAG Pons Medulla PAG Orb DLPT RVM Fields and Price 1997 Fields and Basbaum 1999 Price 1999 Petrovic et al. (2002) Science 295: 1737 -40

INCREASED ACTIVITY DURING ANTICIPATION Wager et al. (2004) Science 303: 1162 -1167 DECREASED ACTIVITY DURING PLACEBO ANALGESIA

Colloca and Benedetti (2005) Nature Rev. Neurosci. 6: 545 -552

10 NOCEBO Pain intensity (NRS) 9 8 7 6 5 4 3 100 2 90 Plasma ACTH (pg/ml) 1 0 0 ACTH 5 10 minutes 80 70 60 50 40 30 20 180 Plasma cortisol (ug/l) 10 170 cortisol 0 160 0 minutes 150 140 130 120 110 100 90 80 Benedetti et al (2006) J Neurosci 26: 12014 -12022 5 0 5 minutes 10 10

10 NOCEBO Pain intensity (NRS) 9 Diazepam 8 7 0. 28 mg/kg 6 5 4 3 100 2 90 Plasma ACTH (pg/ml) 1 0 0 ACTH 5 10 minutes 80 70 60 50 40 30 20 180 Plasma cortisol (ug/l) 10 170 cortisol 0 160 0 minutes 150 140 130 120 110 100 90 80 Benedetti et al (2006) J Neurosci 26: 12014 -12022 5 0 5 minutes 10 10

10 NOCEBO Pain intensity (NRS) 9 8 CCK-A/B blockade 7 Proglumide 6 5 1. 5 mg/kg 4 3 100 2 90 Plasma ACTH (pg/ml) 1 0 0 ACTH 5 10 minutes 80 70 60 50 40 30 20 180 Plasma cortisol (ug/l) 10 170 cortisol 0 160 0 minutes 150 140 130 120 110 100 90 80 Benedetti et al (2006) J Neurosci 26: 12014 -12022 5 0 5 minutes 10 10

NOCEBO Anxiety CCK-A (CCK-1) IC 50 = 6. 3 X 10 -3 M CCK Pain CCK-B (CCK-2) IC 50 = 11 X 10 -3 M ACTH cortisol Benedetti et al (2006) J Neurosci 26: 12014 -12022

Defeat model of anxiety in rats CI-988 CCK-B (CCK-2) receptor antagonist Andre et al. (2005) J. Neurosci. 25: 7896 -7904

CH 3 N O NH Cl N N NH O CH 3 Diazepam L-365, 260 benzodiazepine-based CCK antagonist CCK-A (CCK-1) IC 50 = 280 n. M CCK-B (CCK-2) IC 50 = 2 n M

CCK A/B receptors Nocebo suggestions Colloca and Benedetti (2005) Nature Rev. Neurosci. 6: 545 -552 m-opioid receptors Placebo suggestions

DISEASE/SYSTEM TREATMENT MECHANISM ________________________________________________ Pain Placebo administration Expectation-induced activation of Nocebo administration endogenous opioids and cholecystokinin Verbal suggestions as well as of several brain regions Open vs hidden administration ________________________________________________ Parkinson’s Placebo administration Expectation-induced release of dopamine Disease Nocebo administration in the striatum and changes of firing Verbal suggestions pattern of subthalamic nucleus neurons Open vs hidden administration ________________________________________________ Depression Placebo administration Changes of metabolic responses in different brain regions (inhibition of 5 -HT re-uptake? ) ________________________________________________ Anxiety Placebo administration Change of activity of some brain regions Open vs hidden diazepam ________________________________________________ Addiction Expected vs unexpected Changes of metabolic activity in methylphenidate different brain regions ________________________________________________ Autonomic responses to DBS Open vs hidden DBS Change of neuronal excitability in limbic areas ________________________________________________ Cardiovascular Placebo administration Reduction of b-adrenergic activity of heart ________________________________________________ Respiratory Pharmacological pre-conditioning Conditioning of opioid receptors in with buprenorphine the respiratory centers ________________________________________________ Immune Pharmacological pre-conditioning Conditioning of some immune mediators system with immunosuppressive drugs (e. g. , IL-2, IFN-g, lymphocytes) ________________________________________________ Endocrine Pharmacological pre-conditioning Conditioning of some hormones system with 5 -HT 1 B-1 D receptor agonists (e. g. , growth hormone, cortisol)

Video by Pollo and Benedetti from the DATABASE of Nature Med 2005 table. mpg. 2005

Parkinson’s disease Decrease of raclopride binding de la Fuente-Fernandez et al. ( 2001) Science 293: 1164 -6

Benedetti et al. (2004) Nature Neurosci, 7: 587 -588

“I feel good, I want to stand up” “I feel like after the usual therapy” “I feel much better” 3 2 60 1 40 0 20 30 min 5 10 15 frequency (Hz) rigidity (UPDRS) “I feel like after levodopa” 80 3 80 2 60 1 40 20 30 min 0 0 5 10 15 “I feel better” 3 5 10 15 “I’m falling asleep, like after apomorphine” 3 80 2 60 1 RESPONDERS 40 1 40 20 30 min 0 0 5 10 15 3 80 5 10 15 “I don’t feel any effect” 80 3 2 60 1 20 30 min 5 10 15 “I don’t feel the effect yet” “It doesn’t work” 5 10 15 3 3 2 60 40 0 80 1 40 20 30 min 0 5 10 15 “Why doesn’t it work? ” 5 10 15 “I feel no change” 3 2 60 1 NON-RESPONDERS 80 40 1 40 20 30 min 0 0 5 10 15 Benedetti et al. (2004) Nature Neurosci, 7: 587 -588 5 10 15 80 20 30 min

DISEASE/SYSTEM TREATMENT MECHANISM ________________________________________________ Pain Placebo administration Expectation-induced activation of Nocebo administration endogenous opioids and cholecystokinin Verbal suggestions as well as of several brain regions Open vs hidden administration ________________________________________________ Parkinson’s Placebo administration Expectation-induced release of dopamine Disease Nocebo administration in the striatum and changes of firing Verbal suggestions pattern of subthalamic nucleus neurons Open vs hidden administration ________________________________________________ Depression Placebo administration Changes of metabolic responses in different brain regions (inhibition of 5 -HT re-uptake? ) ________________________________________________ Anxiety Placebo administration Change of activity of some brain regions Open vs hidden diazepam ________________________________________________ Addiction Expected vs unexpected Changes of metabolic activity in methylphenidate different brain regions ________________________________________________ Autonomic responses to DBS Open vs hidden DBS Change of neuronal excitability in limbic areas ________________________________________________ Cardiovascular Placebo administration Reduction of b-adrenergic activity of heart ________________________________________________ Respiratory Pharmacological pre-conditioning Conditioning of opioid receptors in with buprenorphine the respiratory centers ________________________________________________ Immune Pharmacological pre-conditioning Conditioning of some immune mediators system with immunosuppressive drugs (e. g. , IL-2, IFN-g, lymphocytes) ________________________________________________ Endocrine Pharmacological pre-conditioning Conditioning of some hormones system with 5 -HT 1 B-1 D receptor agonists (e. g. , growth hormone, cortisol)

fluorodeoxyglucose (FDG) PET Active fluoxetine Placebo fluoxetine Cognitive therapy Mayberg et al. (2002) Am. J. Psychiat. 159: 728 -737 Benedetti et al. (2005) J. Neurosci. 25: 10390 -10402

fluorodeoxyglucose (FDG) PET 1 week of treatment (no clinical improvement) 6 weeks of treatment (clinical improvement) Fluoxetine Non-responders Fluoxetine responders Placebo responders Mayberg et al. (2002) Am. J. Psychiat. 159: 728 -737 Benedetti et al. (2005) J. Neurosci. 25: 10390 -10402

DISEASE/SYSTEM TREATMENT MECHANISM ________________________________________________ Pain Placebo administration Expectation-induced activation of Nocebo administration endogenous opioids and cholecystokinin Verbal suggestions as well as of several brain regions Open vs hidden administration ________________________________________________ Parkinson’s Placebo administration Expectation-induced release of dopamine Disease Nocebo administration in the striatum and changes of firing Verbal suggestions pattern of subthalamic nucleus neurons Open vs hidden administration ________________________________________________ Depression Placebo administration Changes of metabolic responses in different brain regions (inhibition of 5 -HT re-uptake? ) ________________________________________________ Anxiety Placebo administration Change of activity of some brain regions Open vs hidden diazepam ________________________________________________ Addiction Expected vs unexpected Changes of metabolic activity in methylphenidate different brain regions ________________________________________________ Autonomic responses to DBS Open vs hidden DBS Change of neuronal excitability in limbic areas ________________________________________________ Cardiovascular Placebo administration Reduction of b-adrenergic activity of heart ________________________________________________ Respiratory Pharmacological pre-conditioning Conditioning of opioid receptors in with buprenorphine the respiratory centers ________________________________________________ Immune Pharmacological pre-conditioning Conditioning of some immune mediators system with immunosuppressive drugs (e. g. , IL-2, IFN-g, lymphocytes) ________________________________________________ Endocrine Pharmacological pre-conditioning Conditioning of some hormones system with 5 -HT 1 B-1 D receptor agonists (e. g. , growth hormone, cortisol) Benedetti (2008) Annu Rev Pharmacol Toxicol

Strawberry milk Placebo Cyclosporin A Goebel et al. (2002) FASEB J. 16: 1869 -1873

DISEASE/SYSTEM TREATMENT MECHANISM ________________________________________________ Pain Placebo administration Expectation-induced activation of Nocebo administration endogenous opioids and cholecystokinin Verbal suggestions as well as of several brain regions Open vs hidden administration ________________________________________________ Parkinson’s Placebo administration Expectation-induced release of dopamine Disease Nocebo administration in the striatum and changes of firing Verbal suggestions pattern of subthalamic nucleus neurons Open vs hidden administration ________________________________________________ Depression Placebo administration Changes of metabolic responses in different brain regions (inhibition of 5 -HT re-uptake? ) ________________________________________________ Anxiety Placebo administration Change of activity of some brain regions Open vs hidden diazepam ________________________________________________ Addiction Expected vs unexpected Changes of metabolic activity in methylphenidate different brain regions ________________________________________________ Autonomic responses to DBS Open vs hidden DBS Change of neuronal excitability in limbic areas ________________________________________________ Cardiovascular Placebo administration Reduction of b-adrenergic activity of heart ________________________________________________ Respiratory Pharmacological pre-conditioning Conditioning of opioid receptors in with buprenorphine the respiratory centers ________________________________________________ Immune Pharmacological pre-conditioning Conditioning of some immune mediators system with immunosuppressive drugs (e. g. , IL-2, IFN-g, lymphocytes) ________________________________________________ Endocrine Pharmacological pre-conditioning Conditioning of some hormones system with 5 -HT 1 B-1 D receptor agonists (e. g. , growth hormone, cortisol) Benedetti (2008) Annu Rev Pharmacol Toxicol

Colloca and Benedetti (2005) Nature Rev. Neurosci. 6: 545 -552

Growth hormone 5 4 3 2 1 0 Day 1 0 15 Placebo 30 45 60 5 4 3 2 1 0 Plasma GH (mg/l) Day 3 60 40 20 Sumatriptan 3 2 1 0 -15 Placebo 15 Benedetti et al. (2003) J. Neurosci. 23: 4315 -23 30 45 60 75 minutes 0 15 Placebo 30 45 60 75 minutes 120 100 80 60 40 20 Plasma cortisol (mg/l) 3 4 80 -15 Sumatriptan 4 5 100 120 Sumatriptan 120 Plasma cortisol (mg/l) Day 2 Plasma GH (mg/l) 5 Cortisol 120 75 minutes Plasma cortisol (mg/l) Conditioning with sumatriptan (5 -HT 1 B/1 D agonist) Plasma GH (mg/l) -15 Plasma cortisol (mg/l) Plasma GH (mg/l) Expectation 100 80 60 40 20 Sumatriptan 100 80 60 40 20 -15 Placebo 15 60 75 minutes

? serotonin dopamine 5 -HT D 2 -D 3 anti depressants parkinsonian CCK opioid CCK-A/B mu CCK-8 narcotics Therapeutic effects Negative effects Benedetti (2008) Ann Rev Pharmacol Toxicol, in press Price, Finniss and Benedetti (2008) Annu Rev Psychol, in press

Benedetti et al. (1995) Lancet 346: 1231

en dd i h Benedetti et al. (1995) Lancet 346: 1231 ug dr

computer Open injection BUPRENORPHINE open hidden Hidden injection TRAMADOL open hidden KETOROLAC open hidden METAMIZOL open hidden Pain reduction 0 -1 Pharmacodynamic effect Psychological effect -2 -3 Benedetti et al (1995) Lancet 346: 1231 Amanzio et al. (2001) Pain 90: 205 -15 Colloca et al (2004) Lancet Neurol. 3: 679 -684

TRIAL P 2 (Colloca and Benedetti, Nature Rev Neurosci 6: 545 -552, 2005) Is metamizol (300 mg) effective in post-thymectomy pain? Open metamizol injection group (N=10) Hidden metamizol injection group (N=10) Informed consent “You will receive metamizol but you don’t know when” Double blind

10 Open injection of metamizol Pain intensity (NRS) 8 6 4 2 0 10 Hidden injection of metamizol Pain intensity (NRS) 8 6 4 2 0 0 1 2 3 4 5 6 hours

TRIAL 1 (Colloca et al. Lancet Neurol 3: 679 -684, 2004) Is morphine (0. 14 mg/kg) effective in post-thoracotomy pain? Open morphine injection group (N=21) Hidden morphine injection group (N=21) Informed consent “You will receive morphine but you don’t know when” Double blind

10 Open injection of morphine Pain intensity (NRS) 8 6 4 2 0 10 Hidden injection of morphine Pain intensity (NRS) 8 6 4 2 0 0 1 2 3 4 5 6 hours

TRIAL 3 Colloca et al. Lancet Neurol 3: 679 -684, 2004 Analgesia after interruption of a morphine treatment Open morphine interruption group (N=18) Hidden morphine interruption group (N=18) Informed consent “Your morphine treatment will be stopped but you don’t know when” Double blind

10 Open interruption of morphine Pain intensity (NRS) 8 6 4 2 0 10 Hidden interruption of morphine Pain intensity (NRS) 8 6 4 2 0 1: 00 p. m. 2: 00 3: 00 4: 00 5: 00 6: 00 7: 00 8: 00 9: 00 10: 00

Open stimulation Heart rate (beats/min) 75 70 65 on on off 60 0 1 2 3 4 5 6 minutes Hidden stimulation 75 Heart rate (beats/min) on off 70 65 on on off off computer 60 0 1 2 Colloca et al. (2004) Lancet Neurol. 3: 679 -684 3 4 5 6 minutes

Thalamus Zona incerta Subthalamic nucleus Substantia nigra pars reticulata OPEN STIMULATION “I feel a pleasant sensation” “I feel peaceful, calm” “I want to stand up and walk” “Please, don’t stop the stimulation” 1 VOLT STIMULATION HIDDEN STIMULATION “I feel nothing” “I feel something strange” “I feel excited. . . it’s nice” “Have you turned the stimulator on? ” 3 VOLT STIM. HR Benedetti et al. (2004) Brain Res. Bull. , 63: 203 -211 HR

OPEN (expected stimulation) 20 % HR change 10 0 Zi STN l TN rsa e. S N l do ST idd l m tra r en SN v Lanotte et al. (2005) Brain Behav. Immunity, 19: 500 -509 1 2 3 5 4 Volts

HIDDEN (unexpected stimulation) 20 % HR change limbic associative 10 0 Zi STN l TN rsa e. S N l do ST idd l m tra r en SN v Lanotte et al. (2005) Brain Behav. Immunity, 19: 500 -509 1 2 3 5 4 Volts

How can the recent neurobiological advances on placebos affect current clinical trials and clinical practice?

First implication Any drug may interfere with expectation-activated biochemical pathways, thus confounding the interpretation of clinical trials Colloca and Benedetti (2005) Nature Rev. Neurosci. 6: 545 -552

Benedetti et al. (1995) Lancet 346: 1231 The uncertainty principle imposes limitations on our understanding of the effects of a therapeutic agent. Colloca and Benedetti (2005) Nature Rev. Neurosci. 6: 545 -552

Second implication Expectation can make a big difference in a clinical trial Colloca and Benedetti (2005) Nature Rev. Neurosci. 6: 545 -552

Pain Perceived acupuncture Bausell et al. (2005) Eval Health Prof 28: 9 -26 Perceived sham acupuncture

P a r k i n s o n’ s D i s e a s e Perceived sham surgery Perceived transplantation Mc. Rae et al. (2004) Arch Gen Psychiatry 61: 412 -420

Third implication The placebo effect is a learning phenomenon, thus we can modulate its magnitude Colloca and Benedetti (2005) Nature Rev. Neurosci. 6: 545 -552

Pain tolerance (minutes) 25 25 20 20 15 15 Experimental ischemic arm pain DAY 1 DAY 2 PLA Amanzio & Benedetti (1999) J. Neurosci. 19: 484 -94 DAY 1 DAY 2 DAY 3 KET DAY 4 PLA

Fourth implication These mechanisms can be harnessed to reduce drug intake Colloca and Benedetti (2005) Nature Rev. Neurosci. 6: 545 -552

Placebo buprenorphine request Buprenorphine intake/patient (mg) buprenorphine 1. 2 1. 15 mg/patient 1. 0 0. 8 -33. 8% 0. 76 mg/patient 0. 6 0. 4 0. 2 0 0 Pollo et al. (2001) Pain 93: 77 -84 10 20 30 40 50 Hours from surgery 60 70

Fifth implication Disruption of expectation/placebo mechanisms makes analgesic treatments less effective Colloca and Benedetti (2005) Nature Rev. Neurosci. 6: 545 -552

Alzheimer’s disease Thompson et al. (2003) J. Neurosci. 23: 994 -1005

Normal Frontal Assessment Battery Alzheimer FAB = 17. 4 + 0. 8 FAB = 8. 1 + 1. 8 Connectivity analysis MIXY = Spij log pij pi pj Pain reduction 0 Open lidocaine Hidden lidocaine Pharmacodynamic effect Open lidocaine Hidden lidocaine -1 Psychological effect dose increase -2 -3 Benedetti et al (2006) Pain 121: 133 -144

DISEASE/SYSTEM TREATMENT MECHANISM ________________________________________________ Pain Placebo administration Expectation-induced activation of Nocebo administration endogenous opioids and cholecystokinin Verbal suggestions as well as of several brain regions Open vs hidden administration ________________________________________________ Parkinson’s Placebo administration Expectation-induced release of dopamine Disease Nocebo administration in the striatum and changes of firing Verbal suggestions pattern of subthalamic nucleus neurons Open vs hidden administration ________________________________________________ Depression Placebo administration Changes of metabolic responses in different brain regions (inhibition of 5 -HT re-uptake? ) ________________________________________________ Anxiety Placebo administration Change of activity of some brain regions Open vs hidden diazepam ________________________________________________ Addiction Expected vs unexpected Changes of metabolic activity in methylphenidate different brain regions ________________________________________________ Autonomic responses to DBS Open vs hidden DBS Change of neuronal excitability in limbic areas ________________________________________________ Cardiovascular Placebo administration Reduction of b-adrenergic activity of heart ________________________________________________ Respiratory Pharmacological pre-conditioning Conditioning of opioid receptors in with buprenorphine the respiratory centers ________________________________________________ Immune Pharmacological pre-conditioning Conditioning of some immune mediators system with immunosuppressive drugs (e. g. , IL-2, IFN-g, lymphocytes) ________________________________________________ Endocrine Pharmacological pre-conditioning Conditioning of some hormones system with 5 -HT 1 B-1 D receptor agonists (e. g. , growth hormone, cortisol)

Department of Neuroscience University of Turin Medical School and National Institute of Neuroscience Turin, Italy www. personalweb. unito. it / fabrizio. benedetti NEUROPHYSIOLOGY Antonella Pollo Luana Colloca PSYCHOLOGY Martina Amanzio Claudia Arduino Sara Costa NEUROLOGY Bruno Bergamasco Leonardo Lopiano Innocenzo Rainero Giovanni Asteggiano Luisella Tarenzi Elena Torre NEUROSURGERY BIOENGINEERING Sergio Vighetti Michele Lanotte Antonio Melcarne SURGERY Giuliano Maggi Caterina Casadio Anna Arslanian RESPIRATORY PATHOPHYSIOLOGY Sergio Baldi