Effects of Seal Oil Supplementation on Risk Factors for Cardiovascular Disease in Human Subjects Conference on Seal Oil, Collagen, and Protein Products June 7-8 th, DFAIT, Ottawa Professor Bruce J. Holub Department of Human Biology and Nutritional Sciences University of Guelph Guelph, ON Canada N1G 2W1

Fatty Acid Composition of Encapsulated Seal Oil Fatty Acids Seal Oil (% of total) ΣSats 11.9 ΣMono :1n :1n :1n ΣPUFA 29.6 n n :5 (EPA) :5 (DPA) :6 (DHA) 10.4

DPA Docosapentaenoic Acid 22:5 n-3

Rationale for Research/Health Interest in Dietary Docosapentaenoic Acid (DPA, 22:5n-3) 1.) Is a substantial component of the Greenland Inuit diet rich in marine mammals (Bang et al., AJCN, 33: , 1980) and diet of Inuit in northern Quebec. 2.) Fish oils enriched in EPA/DHA (low DPA) and seal oils contain EPA/DHA plus significant levels of DPA. 3.) DPA levels in serum phospholipid have been inversely correlated with coronary heart disease risk (Simon et al., Am. J. Epid., 142: , 1995). 4.) Might DPA offer any potential benefits with respect to CVD/cardioprotection?

Principle Meat/Fish Consumed by Selected Households in Qeqertarsuaq, (source: field data) Polar Bear 1% Fish 24% Seal/Walrus 20% Other 4% Minke Whale 6% Birds 12% Lamb 3% Imported Foods 16% Beluga/Narwhal 7% Caribou 7%

The Fatty Acid Comparisons of Serum Phospholipids of Postmenopausal Women From Greenland and Canada Stark KD, Mulvad G, Pedersen HS, Park EJ, Dewailly E, and Holub BJ. University of Guelph, Guelph, ON, Canada Center of Primary Health Care, Nuuk, Greenland Laval University, QC, Canada

Comparison of n-3 Fatty Acid Compositions of Serum Phospholipid in Postmenopausal Women (mean ± SEM) Ref: Stark et al., Nutrition, 18: , Canada Greenland * * * EPA (20:5n-3) DHA (22:6n-3) DPA (22:5n-3)

Epidemiological/Population Studies 1.) Higher levels of docosahexaenoic acid (DHA, 22:6 n-3) and docosapentaenoic acid (DPA, 22:5 n-3) in serum phospholipid have been associated with decreased coronary heart disease risk. (Simon et al., Am. J. Epidemiol., 142: , 1995.) 2.) Higher levels of eicosapentaenoic acid (EPA, 20:5 n-3) and docosapentaenoic acid (DPA, 22:5 n-3) in platelet phospholipid have been associated with reduced coronary artery disease (Hodgson et al., AJCN, 58: , 1993).

Ref: Rissanen et al., Circulation, 102: , Relative Risk of Acute Coronary Events in Relation to Serum DHA and DPA Levels DHA + EPA as % of total serum fatty acids < >3.58 Relative Risk (RR)

Dietary Vegetable Oils As Source of Omega-3 α-Linolenic Acid 18:3n-3 (Canola, Flaxseed, Soybean) 18:4n-3 20:4n-3 20:5n-3 22:5n-3 22:6n-3 Desaturation Elongation Desaturation Elongation Desaturation Dietary Fish/Fish Oil (EPA/DHA) (EPA) (DHA)

% of day 0 levels Omega-3 Levels in Total Human Platelet Phospholipid (after flax rich in α-LNA) 20:5n-3 EPA 22:5n-3 DPA 22:6n-3 DHA * *

Effects of Dietary Consumption of Omega-3 Fatty Acids on Physiological DPA (22:5n-3) Status* Dietary Fatty Acids/Oils DPA Status 1) α–LNA (flax, canola) 2) EPA + DHA (fish oils) 3) EPA alone 4) DHA alone 5) EPA + DHA + DPA (seal oil) *Based on DPA (22:5n-3) levels in human serum/platelet phospholipid.

Common Dietary Sources (N. Am.) of DPA (22:5 n-3) in Cellular Phospholipid 1.) α–LNA (18:3 n-3): via desaturation/elongation (approx. 150mg/day of DPA generated per 1.5g α-LNA/diet) 2.) EPA (20:5 n-3): via elongation (<50mg/day of DPA generated) 3.) DPA (22:5n-3): direct consumption (approx. 18mg/day in N. Am. and approx. 1,000-3,000 mg/day in Greenland Inuit) 4.) DHA (22:6n-3): via retroconversion (<50mg/day of DPA generated)

Effects of Supplementation with Dietary Seal Oil on Selected Cardiovascular Risk Factors And Hemostatic Variables in Healthy Male Subjects Conquer J, Cheryk L, Chan E, Gentry P, & Holub B. University of Guelph

Subjects: 20 healthy males (29.5 ± 1.5 yr) Supplement: 20 g/day of encapsulated plant oil (placebo) or seal oil (providing 0.8g DPA plus 1.3 g EPA plus 1.7 g DHA/day) Duration: 42 days with blood sampling and analysis at days 0, 21, and 42. Experimental Design

% of fatty acids in serum PL EPA DPA DHA * * * * * * Day Day

( by 7%) ( by 19%) Seal Oil * Placebo (Oil) Fibrinogen (g/L) Protein C (u/mL) * Days

(EPA+DHA) as % of Fatty Acids in Plasma Phospholipid Relative Risk (IHD/MI) (Ref. Lemaitre et al., Am J Clin Nutr, 77:319, 2003) 36 non-fatal MI (one SD above mean) Fatal Ischemic Heart Disease (one SD above mean) 70% lower

(EPA + DHA) Levels and Risk of Fatal Ischemic Heart Disease CHD Risk (desirable) HighMediumLow (EPA + DHA as % of fatty acids in serum phospholipid) Ref: Based on Lemaitre et al., Am. J. Clin. Nutr., 77:319 (2003) Before 11.0 After

Docosahexaenoic acid and docosapentaenoic acid incorporated into human platelets after 24 and 72 hours: Inhibitory effects on platelet reactivity L.A. Cheryk, J.A. Conquer, B.J. Holub, P.A. Gentry University of Guelph, Guelph, Ontario, Canada Ref: Platelet, 10: , 1999.

Effect of DPA (22:5n-3) Addition (at 200 uM) on Thromboxane B 2 Generation and Collagen- Induced Human Platelet Aggregation %age of Controls Incubation time TxB 2 release % Max. Aggregation 24 hours hours 41 0