Juvecol® Clinical Evidence

Najima M, et al. Usefulness of the supplement containing proteoglycan for Japanese healthy people feeling knee’s discomfort. 2016;53(3):64-71.

Topic:

Can salmon PG improve knee discomfort in healthy people?

Background:

Age-related changes in the extracellular matrix (ECM) of cartilage, which contains various types of collagen and proteoglycan, contribute to the development of osteoarthritis. Can supplemental PG help?

Study Type:

Human clinical intervention trial

Study Design:

Randomized, placebo-controlled, double-blind. Participants were randomly divided into two groups: the treatment group, which received salmon PG daily, and the placebo group, which received placebo tablets. Pain VAS (measuring pain while lying down, walking, and going up and down stairs), range of motion, and modified J-KOOS (measuring stiffness, pain, function, and quality of life) were assessed at baseline and at 4, 8, and 12 weeks.

Dosage:

10 mg/day for 12 weeks

Subjects:

31 healthy people, between the ages of 40 and 69, experiencing knee discomfort

Results:

Pain VAS: Knee pain improved significantly from baseline among participants taking salmon PG. Comparing the salmon PG group to the placebo group, there was a statistically significant difference in pain upon climbing up and down stairs.

Range of motion: Knee extension and flexion improved significantly in the salmon PG group compared to baseline after 4, 8, and 12 weeks of ingestion. There were also significant improvements in knee extension and flexion in the salmon PG group versus the placebo group after 12 weeks.

Modified J-KOOS: All four indices evaluated — stiffness, pain, function, and quality of life — showed improvement among those taking salmon PG versus those taking placebo.

Conclusion:

“It is suggested that the ingestion of the supplement containing proteoglycan by Japanese healthy people feeling knee’s discomfort for 12 weeks contributed to improving the joint support.”

Tomonaga, et al.  Evaluation of the effect of salmon nasal proteoglycan on biomarkers for cartilage metabolism in individuals with knee joint discomfort: A randomized double-blind placebo-controlled clinical study. 2017 Jul;14(1):115-126.

Topic:

Can salmon PG exert a protective effect on cartilage cells in joints among people with knee discomfort?

Background:

A previous open-label study by the same authors found that salmon PG alleviates symptoms of osteoarthritis, possibly by reducing the degradation of type II collagen. Can the results be replicated in a controlled clinical trial?

Study Type:

Human clinical intervention trial

Study Design:

Randomized, placebo-controlled, double-blind, parallel group. Participants were randomly assigned to receive either salmon PG or placebo. Researchers measured markers for type II collagen degradation (C1, C2) and synthesis (PIICP), as well as the ratio between the two, at baseline and at 16 weeks.

Dosage:

10 mg/day for 16 weeks

Subjects:

55 men and women (average age 52.4 years) with knee discomfort but without diagnosis of knee osteoarthritis

Results:

Among participants with either high levels of knee pain and physical dysfunction or constant knee pain in the salmon PG group, there was a significant change in C1, C2 levels compared with those in the placebo group after 16 weeks of intervention. The C1, 2C/PIICP ratios decreased in the salmon PG group (meaning less collagen degradation to more collagen synthesis), while they increased slightly in the placebo group (meaning more collagen degradation to less collagen synthesis).

Conclusion:

“Therefore, oral administration of salmon nasal cartilage proteoglycan at a dose of 10 mg/day may exert a chondroprotective action in subjects with knee joint discomfort. This effect was achieved by improving cartilage metabolism (reducing type II collagen degradation and enhancing type II collagen synthesis), without causing apparent adverse effects.”