Shark Cartilage
  
Shark Cartilage
Background
Shark cartilage is one of the most popular supplements in the United States, with over 40 brand name products sold in 1995 alone. Primarily used for cancer, its use became popular in the 1980s after several poor-quality studies reported "miracle" cancer cures.
Laboratory research and animal studies of shark cartilage or the shark cartilage derivative product AE-941 (Neovastat®) have demonstrated some anti-cancer (anti-angiogenic) and anti-inflammatory properties. However, there is currently not enough reliable human evidence to recommend for or against shark cartilage for any condition. There are several ongoing cancer studies. Many trials are supported by manufacturers of shark cartilage products, raising questions about impartiality.
Commercial shark cartilage is primarily composed of chondroitin sulfate (a type of glycosaminoglycan), which is further broken down in the body into glucosamine and other end products. Although chondroitin and glucosamine have been extensively studied for osteoarthritis, there is no evidence supporting the use of unprocessed shark cartilage preparations for this condition. Shark cartilage also contains calcium (up to 600-780mg of elemental calcium/daily dose). Manufacturers sometimes promote its use for calcium supplementation.
Shark cartilage supplements at common doses can cost as much as $700-1000 per month.
Synonyms
AE-941, cartilage, Haifischknorpel (German), Houtsmuller Diet, Neovastat, shark, shark fin soup, Sphyrna lewini (hammerhead shark), Squalus acanthias (spiny dogfish shark), squalamine, U-955.
Note : The product Catrix® is made from cow cartilage, not from shark cartilage.
Evidence
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
Uses based on scientific evidenceGrade*Cancer
For several decades, shark cartilage has been proposed as a cancer treatment. Studies have shown shark cartilage or the shark cartilage product AE-941 (Neovastat®) to block the growth of new blood vessels, a process called "anti-angiogenesis," which is believed to play a role in controlling growth of some tumors. There have also been several reports of successful treatments of end-stage cancer patients with shark cartilage, but these have not been well designed or included reliable comparisons to accepted treatments. Many studies have been supported by shark cartilage product manufacturers, which may influence the results. In the United States, shark cartilage products cannot claim to cure cancer, and the Food and Drug Administration (FDA) has sent warning letters to companies not to promote products in this way. Without further evidence from well-designed human trials, it remains unclear if shark cartilage is of any benefit in cancer and patients are advised to check with their doctor and pharmacist before taking shark cartilage.
C
Arthritis
Chondroitin sulfate, a component of shark cartilage, has been shown to benefit patients with osteoarthritis. However, the concentrations of chondroitin in shark cartilage products may be too small to be helpful. The ability of shark cartilage to block new blood vessel growth or reduce inflammation is proposed to be helpful in rheumatoid arthritis. However, there is limited research in these areas, and more studies are needed before a recommendation can be made.
C
Macular degeneration
It is proposed that shark cartilage or the shark cartilage product AE-941 (Neovastat®) may be helpful in patients with macular degeneration. A small amount of research suggests possible benefits, but more study is needed before a recommendation can be made.
C
Psoriasis
Shark cartilage products have been tested by mouth or on the skin in people with psoriasis. However, no clear benefits have been shown. More research is needed before a conclusion can be drawn.
C
Pain
Based on laboratory studies, shark cartilage may reduce inflammation. However, it is unclear if shark cartilage is a safe or helpful treatment for pain in humans.
C
* Key to grades
A: Strong scientific evidence for this use;
B: Good scientific evidence for this use;
C: Unclear scientific evidence for this use;
D: Fair scientific evidence against this use (it may not work);
F: Strong scientific evidence against this use (it likely does not work).
Uses based on tradition or theory
The below uses are based on tradition or scientific theories. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
Allergic skin rashes, ankylosing spondylitis, atherosclerosis ("hardening" of the arteries), bacterial infections, diabetic retinopathy, diarrhea, immune system stimulant, intestinal disorders and inflammation, fungal infections, glaucoma, Kaposi's sarcoma, kidney stones, Reiter's syndrome, rheumatoid arthritis, sarcoidosis, scar healing, Sjogren's syndrome, skin rash, systemic lupus erythematosus (SLE), wound healing, wrinkle prevention.
Dosing
The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.
Standardization
Standardization involves measuring the amount of certain chemicals in products to try to make different preparations similar to each other. It is not always known if the chemicals being measured are the "active" ingredients. There is no well-accepted method of preparing or purifying shark cartilage products, although manufacturers may use specific procedures to control their own processes. Shark cartilage products are often made by sterilizing and grinding dried shark cartilage (hammerhead or spiny dogfish shark) into a powder form. Some manufacturing processes can destroy the proteins that are believed to slow cancer growth. Analysis of one shark cartilage product found it to contain more than 99% water.
Adults (18 years and older)
Cancer : Studied doses of ground cartilage extract include 80 to 100 grams, or 1.0 to 1.3 grams per kilogram of body weight, taken by mouth daily, divided into 2 to 4 doses. Doses of the shark cartilage derivative AE-941 (Neovastat®), available in clinical trials, have ranged from 30 to 240 milliliters per day taken by mouth, or 20 milligrams per kilogram taken twice daily. Rectal doses of 15 grams per day or 0.5 to 1.0 grams per kilogram of body weight per day in 2 to 3 divided doses (prepared as an enema) have also been studied.
Arthritis : Doses of 0.2 to 2.0 grams per kilogram of body weight per day, taken by mouth in 2 to 3 divided doses, have been studied.
Psoriasis : Doses of 0.4 to 0.5 grams per kilogram of body weight per day, taken by mouth for four weeks, have been used. If skin lesions improve, doses have been reduced to 0.2 to 0.3 grams per kilogram per day for four additional weeks. Creams applied to the skin with 5% to 30% shark cartilage are available, and have been recommended by some practitioners for treatment of psoriasis alone or with shark cartilage by mouth, for 4 to 6 weeks. Studies have used 5% to 10% preparations applied daily.
Children (younger than 18 years)
Shark cartilage is not recommended in children due to lack of scientific study and a theoretical risk of blocking blood vessel growth. There is one report of a nine year-old child with a brain tumor treated with shark cartilage who died four months later.
Safety
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.
Allergies
Allergic reactions to shark cartilage or to any of its ingredients are possible, although there is limited human information in this area.
Side Effects and Warnings
A limited amount of published research suggests that shark cartilage is well tolerated in most people at recommended doses. An 18-month study in 330 people by the makers of the shark cartilage derivative Neovastat® did not report any major toxicities after being exposed to the product for more than 4 years. The most common adverse effects reported are mild-to-moderate stomach upset and nausea. In several studies, 5% to 10% of patients stopped taking shark cartilage due to gastrointestinal distress (nausea, vomiting, constipation, dyspepsia), while 20% to 40% experienced milder symptoms of cramping or bloating. Gastrointestinal upset may be due to the high calcium concentration in some shark cartilage preparations. There is one report of liver damage in an elderly male using shark cartilage, which resolved six-weeks after the supplement was stopped. One study reports taste alteration to be a frequent side effect, observed in up to 14% of patients.
Uncommon side effects reported in studies or historically include confusion, decreased muscle strength, decreased sensation, weakness, dizziness, fatigue, increased or decreased blood sugar levels, and low blood pressure. Shark cartilage products may contain high levels of calcium, which may be harmful to patients with kidney disease, abnormal heart rhythms, a tendency to form kidney stones, and those with cancers that raise calcium levels (breast, prostate, multiple myeloma, squamous cell lung cancer, and others). In theory, due to the blocking of new blood vessel growth, shark cartilage may be harmful in people with heart disease or narrowed blood vessels of the legs (peripheral vascular disease). In theory, wound healing and recovery from surgery or trauma may be reduced.
Limited evidence suggests that shark cartilage may lower blood sugar levels. Caution is advised in patients with diabetes or hypoglycemia, and in those taking drugs, herbs, or supplements that affect blood sugar. Serum glucose levels may need to be monitored by a healthcare provider, and medication adjustments may be necessary.
One case report implicates inhaled shark cartilage dust in an asthma exacerbation and resulting death of a 38-year-old male.
Pregnancy and Breastfeeding
Shark cartilage is not recommended in pregnant or breastfeeding women. Shark cartilage may block the growth of new blood vessels, and drugs with similar properties, such as thalidomide, can cause birth defects. There is limited study of shark cartilage in these areas.
References
1. Batist G, Patenaude F, Champagne P, et al. Neovastat (AE-941) in refractory renal cell carcinoma patients: report of a phase II trial with two dose levels. Ann Oncol 2002;13(8):1259-1263.
2. Beliveau R, Gingras D, Kruger EA, et al. The antiangiogenic agent neovastat (AE-941) inhibits vascular endothelial growth factor-mediated biological effects. Clin Cancer Res 2002;8(4):1242-1250.
3. Berbari P, Thibodeau A, Germain L, et al. Antiangiogenic effects of the oral administration of liquid cartilage extract in humans. J Surg Res 1999;87(1):108-113.
4. Boivin D, Gendron S, Beaulieu E, et al. The antiangiogenic agent Neovastat (AE-941) induces endothelial cell apoptosis. Mol Cancer Ther 2002;1 (10) :795-802.
5. Bukowski RM. AE-941, a multifunctional antiangiogenic compound: trials in renal cell carcinoma. Expert Opin Investig Drugs 2003;12(8):1403-1411.
6. Dupont E, Falardeau P, Mousa SA, et al. Alaoui-Jamali MA. Antiangiogenic and antimetastatic properties of Neovastat (AE-941), an orally active extract derived from cartilage tissue. Clin Exp Metastasis 2002;19(2):145-153.
7. Dupont E, Savard RE, Jourdain C, et al. Antiangiogenic properties of a novel shark cartilage extract: potential role in the treatment of psoriasis. J Cutan Med Surg 1998;2(3):146-152.
8. Escudier B, Patenaude F, Bukowski R, et al. Rationale for a phase III clinical trial with AE-941 (Neovastat ®) in metastatic renal cell carcinoma patients refractory to immunotherapy. Ann Oncol 2000;11(supplement 4):143-144.
9. Gingras D, Boivin D, Deckers C, et al. Neovastat-a novel antiangiogenic drug for cancer therapy. Anticancer Drugs 2003;14(2):91-96.
10. Jagannath S, Champagne P, Hariton C, et al. Neovastat in multiple myeloma. Eur J Haematol 2003;70(4):267-268. <
11. Jamali MA, Riviere P, Falardeau A, et al. Effect of AE-941 (Neovastat), an angiogenesis inhibitor, in the Lewis lung carcinoma metastatic model, efficacy, toxicity prevention and survival. Clin Invest Med 1998;(suppl):S16.
12. Kralovec JA, Guan Y, Metera K, et al. Immunomodulating principles from shark cartilage. Part 1. Isolation and biological assessment in vitro. Int Immunopharmacol 2003(5):657-669.
13. Lagman R, Walsh D. Dangerous nutrition? Calcium, vitamin D, and shark cartilage nutritional supplements and cancer-related hypercalcemia. Support Care Cancer 2003;11(4):232-235.
14. Leitner SP, Rothkopf MM, Haverstick DD, et al. Two phase II studies of oral dry shark cartilage powder (SCP) in patients with either metastatic breast or prostate cancer refractory to standard treatment. Amer Soc Clin Oncol 1998;17:A240.
15. Miller DR, Anderson GT, Stark JJ, et al. Phase I/II trial of the safety and efficacy of shark cartilage in the treatment of advanced cancer. J Clin Oncol 1998;16(11):3649-3655.
16. Ortega HG, Kreiss K, Schill DP, et al. Fatal asthma from powdering shark cartilage and review of fatal occupational asthma literature. Am J Ind Med 2002;42(1):50-54.
17. Riviere M, Alaoui-Jamali M, Falardeau P, et al. Neovastat: an inhibitor of angiogenesis with anti-cancer activity. Proc Amer Assoc Cancer Res 1998;39:46.
18. Riviere M, Falardeau P, Latreille J, et al. Phase I/II lung cancer clinical trial results with AE-941 (Neovastat) an inhibitor of angiogenesis. J Clin Pharm 1998;38(9):860.
19. Riviere M, Latreille J, Falardeau P. AE-941 (Neovastat), an inhibitor of angiogenesis: phase I/II cancer clinical trial results. Cancer Invest 1999;17(suppl 1):16-17.20. Sauder DN, Dekoven J, Champagne P, et al. Neovastat (AE-941), an inhibitor of angiogenesis: Randomized phase I/II clinical trial results in patients with plaque psoriasis. J Am Acad Dermatol 2002;47(4):535-41.
20. Sheu JR, Fu CC, Tsai ML, et al. Effect of U-995, a potent shark cartilage-derived angiogenesis inhibitor, on anti-angiogenesis and anti-tumor activities. Anticancer Res 1998;18(6A):4435-4441.
21. Wilson JL. Topical shark cartilage subdues psoriasis. Altern Comp Ther 2000;6:291.
December 01, 2003 
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