2/5/2015. Sensitive: Discriminative: Simple Inexpensive. Example of a good biomarker: blood tests, CSF test but they are not discriminative for PD

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1 Jeffrey H. Kordower, Ph.D.. Department of Neurological Sciences Rush University Medical Center Sensitive: Discriminative: Simple Inexpensive Example of a good biomarker: blood tests, CSF test but they are not discriminative for PD TH immunohistochemistry in the Putamen of human brain Control 1 years PD 4 years PD 5 years PD 11 years PD 15 years PD 21 years PD 3 1

2 50% DA neurons at symptom onset; rapid decline over 5y Premotor symptoms olfactory dysfunction autonomic dysfunction constipation depression, anxiety REM behavior disorder executive dysfunction Signs/findings presynaptic DA echogenicity of the SN hyposmia slight motor signs Berg. Neurodegenerative Diseases. 2008;5:133 Parkinson s disease is caused by exposure to lipopolysaccharide(bacterial endotoxin), which promotes α-synuclein overexpression/aggregation in neurons of the submucosal plexus of the gastrointestinal system, then spreads via neural networks, to the medulla, then rostally, with cumulative neurological signs. cerebral cortex, neocortex DMN X, II raphe, II LC, II SN, IV cerebral cortex, mesocortex SN, IV Aurbach, V basal, mid and forebrain amygdala, hypothalamus, thalamus pontine tegmentum medulla oblongata Braak & Del Tredici. Neurology 2008;70:1916 2

3 Braak & Del Tredici. Neurology. 2008;70:1916. a putative environmental pathogen might induce α-synuclein misfolding and aggregation in specific cell types of the submucosal plexus and reach the brain via a consecutive series of projection neurons. Braak et al. Neuroscience Lettters 2006;396: Grafts of dopamine cells placed into the striatum with viral overexpression of alpha synuclein Note the physical segregation of the graft (brown) and gene delivery (black) Kordower et al., Neurobiology of Disease, in press. 3

4 A small percentage (5%) of grafted neurons retrogradely transported host-derived alpha synuclein Kordower et al., Neurobiology of Disease, in press. Host nigra Synuclein Ubiquitin Grafted neurons Synuclein Ubiquitin Kordower et al. Nat Med 2009;34: Honolulu Heart Program 8,006 Japanese Honolulu-Asia Aging Study 3,741 Japanese (80% of survivors of HHP) 4

5 Bowel movements Sample size Incident PD cases* Incidence/10K person-years Unadjusted Ageadjusted < > Test for trend P=0.002 P=0.005 Overall Appears highest in men with <1BM/day and laxatives > 2/week: 51.6/10,000 person years Honolulu Health & Aging Study. Abbott et al. 2001;57(3):456. Can we demonstrate early GI involvement in PD? biopsy distal colon in early PD Is the gut leaky in PD subjects? intestinal permeability studies evidence for endotoxin exposure Systemic local Do PD subjects have dysbiosis? (alterations in intestinal flora) DNA fingerprinting Early untreated classical PD nocoagulopathy, alcoholism, occupational exposure to microbes, primary GI disease Unpreppedflexible sigmoidoscopywith biopsy immunohistochemistry(synuclein, nitrotyrosine) Differential sugar absorption sugar ingestion 24-hour urine collection with assays 16S rrna fingerprinting for dysbiosis 5

6 Median Age/sex Disease Duration Onset /dx (y) tupdrs HY #BM/d 55M 4/ M 1/ M 1/ <1 78M 1/ M 4/ <1 68F 0.5/ F 2/ <1 49M 8/ M 1/ M 2/ / Controls (N=26) Crohn s(n=14) Ulcerative colitis (N=11) Age,median(range) 54 (36-71) 40 (24-72) 43 (21-62) Gender, male 12 (46%) 6 (55%) 4(36%) Parkinson disease Crohn s disease Control 6

7 Alpha synuclein Nitro-tyrosine Parkinson s A B C D Ulcerative Colitis E F Aged-Matched Control 85-y/o woman Psychotic depression 2002 ECT MCI Rest tremor 2/2010 α-synuclein A N-tyrosine B C D Colonic polyp biopsied MPTP low MPTP high Aged low Aged high Young control low Young control high 7

8 Alpha syn TH Merged Sugar Sucrose Lactose/mannitol Sucralose Site Gastric Enteric colonic 24-hour sucralose excretion 2.5 *p= control PD 8

9 LBP (ng/ml) *p= control PD 1 kg bacteria most unknown identity most anaerobic luminal population & mucosal biofilm microbes/ml luminal content Established by age 2; stable Important because genetic component (100x as many genes ) metabolic efficiency energy homeostasis important in systemic inflammation HIV, coronary artery disease, insulin resistance, EtOH liver disease Gram ( ) rods bacteroides desulfovibrios escherichia fusobacteria Gram (+) c0cci ruminococci peptostreptococci peptococci streptococci Gram (+) rods eubacteria bifidobacteria clostridia lactobacilli propioibacteria actinomyces Gram (+) coccobacilli methanobrevibacter Salminen et al. Br J Nutr 1998;80:S147. 9

10 Method Advantages Disadvantages morphology/biochemistry straightforward, cheap subjective, culturable only specific biomarkers may not require culture can t help with unknown species, requiresunique biomarker ribotyping(rna polymorphisms) reliable, high discriminatory power 16S ribosomal RNA typing high fidelity, reliable, cumulativedatabase, culturable& nonculturable culturable only costly Salminen et al. Br J Nutr 1998;80:S147. Age, median (range) Parkinson disease (N=10) Crohn s disease (N=11) Ulcerative colitis (N=13) Controls (N=26) 57 (46-79) 40 (24-72) 42 (21-62) 55 (36-71) Gender, male 70% 55% 31% 46% Duration PD (y) Median (range) 1.5 (0.5-8) Total UPDRS 22 (15-28) HY Stage I II 2 8 Healthy Lumen Parkinson lumen 100% 100% 90% 90% 80% 80% 70% 70% 60% 60% 50% 50% 40% 40% 30% 30% 20% 20% 10% 10% 0% % Healthy sigmoid Parkinson's sigmoid 100% 100% 90% 90% 80% 80% 70% 70% 60% 60% 50% 50% 40% 40% 30% 30% 20% 20% 10% 10% 0% %

11 PCO case scores (Bray Curtis) Control lumen 0.2 Axis Control mucosa Parkinson mucosa Parkinson lumen Axis All Parkinson Age/sex Disease tupdrs HY #BM/d α-synuclein nitrotyrosine Abn mucosa Abn Duration lumen (y) 55M M M < M M < F F < M M M

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13 GI changes, such as a leaky gut or alpha synucleinin the colon demonstrates excellent sensitivity Colonic biopsies can be a sensitive and inexspensive biomarker Still to be proven is how specific this potential biomnarkeris and studies in PSP and MSA patients are currently underway Kathleen Shannon, M.D. Ali ]Keshavarzian, M.D. Christopher Forsyth Hemraj Dodiya Leo Kelly 13