Fish Protein Stimulated the Fibrinolysis in Rats

Abstract

Objective: We hypothesized that fish protein affects blood coagulation and/or fibrinolysis, and compared the activity and amounts of factors involved in blood coagulation and fibrinolysis in rats fed the fish protein, which was treated to remove water-soluble and ethanol-soluble elements, from sardine (sardine protein). Methods: In the first experiment, rats were fed for 21 days an AIN-93G-based control diet, and diets in which the casein of the control diet was exchanged for sardine protein at 5, 10 and 20% levels. In the second experiment, rats were fed an AIN-93G control diet and diets containing 5% fish oil, 10% sardine protein or both (5% fish oil + 10% sardine protein) for 21 days. At the end of the experiments, blood coagulation time, hemostatic parameters and fibrinolysis parameters were measured. Results: The activated partial thromboplastin time (APTT), which is an assay for blood coagulation time in the intrinsic blood coagulation pathway, of rats fed the 20% sardine protein diet was significantly prolonged compared to that of rats fed the control diet. The prolonged APTT by dietary sardine protein was due to a significant decrease of the activities of plasma blood coagulation factors VIII, IX, XI and XII. On the other hand, dietary sardine protein significantly increased the activity of tissue-type plasminogen activator, and the amount of plasma plasmin–α₂-plasmin inhibitor complex, which are markers of activated plasmin. Moreover, we observed that the 20% sardine protein diet increased the amount of plasma D-dimer, which is a degraded product of the fibrin polymer by plasmin. In the second experiment, the APTT and PT of rats fed the F diet were prolonged compared to those of rats fed the control diet, however the concentration and amount of fibrinolytic parameters in the plasma were almost the same as those of rats fed the control diet. In contrast, the F+S diet not only prolonged APTT and PT, but also increased the concentration and amount of fibrinolytic parameters in plasma. Conclusions: We consider that the beneficial effects to health and amelioration of cardiovascular and cerebrovascular diseases by fish consumption are caused by a combination of the suppressing effect on blood coagulation of n–3 polyunsaturated fatty acids and the promoting effect on fibrinolysis of fish protein.

Assessment of Anti-Aging Effects of Fish Products Peptide in Middle-Aged Subjects

“…It is known that DHA is effective for prevention and improvement of cerebrovascular disorders, dementia, ischemic heart disease, high blood pressure, arteriosclerosis, chronic inflammation, hyperlipidemia, and dermatitis by decreasing arachidonic acid in plasma and internal organs [22][23][24][25] . The beneficial effects to health and amelioration of cardiovascular and cerebrovascular diseases due to fish are caused by a combination of the suppressing effect on blood coagulation of n-3 PUFA and the promoting effect on fibrinolysis of fish protein 26) . However, it has been reported that DHA supplementation increased oxidative damage in bone marrow DNA 27) .…”

Comparative Fibrinolysis

“…The genes encoded for Plg and tPA were identified in the blowfish Fugu rubripes (Jiang and Doolittle 2003). Rats with diets based on fish oil decrease the fibrinolytic activity due to an increase of PAI-1 (Sano et al 2003), whereas dietary supplementation with fish protein increases fibrinolysis by increasing tPA in blood (Murata et al 2004). …”

<i>L</i>-Cysteine Down-Regulates SREBP-1c-Regulated Lipogenic Enzymes Expression via Glutathione in HepG2 Cells

“…A series of studies found that soy protein [1][2][3][4] and fish protein [5] are capable of lowering blood lipid levels when compared with casein as a control protein. Moreover, it has been reported in a few studies that soy protein is capable of altering the transcription levels of hepatic sterol regulatory element-binding proteins (SREBPs) which in turn leads to the observed lipidlowering effect [2,4,6] .…”