Evaluation and Validation of a Joint Stress Test to Induce Activity-Related Knee Joint Discomfort - a Prospective Case-Control Study.

BACKGROUND: The assessment of improvement or maintenance of joint health in healthy subjects is a great challenge. The aim of the study was the evaluation of a joint stress test to assess joint discomfort in subjects with activity-related knee joint discomfort (ArJD). RESULTS: Forty-five subjects were recruited to perform the single-leg-step-down (SLSD) test (15 subjects per group). Subjects with ArJD of the knee (age 22-62 years) were compared to healthy subjects (age 24-59 years) with no knee joint discomfort during daily life sporting activity and to subjects with mild-to-moderate osteoarthritis of the knee joint (OA, Kellgren score 2-3, age 42-64 years). The subjects performed the SLSD test with two different protocols: (I) standardization for knee joint discomfort; (II) standardization for load on the knee joint. In addition, range of motion (ROM), reach test, acute pain at rest and after a single-leg squat and knee injury, and osteoarthritis outcome score (KOOS) were assessed. In OA and ArJD subjects, knee joint discomfort could be reproducibly induced in a short time interval of less than 10 min (200 steps). In healthy subjects, no pain was recorded. A clear differentiation between study groups was observed with the SLSD test (maximal step number) as well as KOOS questionnaire, ROM, and reach test. In addition, a moderate to good intra-class correlation was shown for the investigated outcomes. CONCLUSIONS: These results suggest the SLSD test is a reliable tool for the assessment of knee joint health function in ArJD and OA subjects to study the improvements in their activities. Further, this model can be used as a stress model in intervention studies to study the impact of stress on knee joint health function.

Bioavailability Study of Maqui Berry Extract in Healthy Subjects.

Several health promoting effects have been reported for maqui berry, rich in anthocyanins. Direct effects of anthocyanins as well as bioactive metabolites might be involved. Within the study, bioavailability of a proprietary standardized maqui berry extract Delphinol® was investigated based on two selected anthocyanins (delphinidin-3-O-glucoside (DS) + cyanidin-3-O-sambubioside (CS)) and two breakdown products (protocatechuic acid (PCA) + gallic acid (GA)) after a single-dose supplementation in humans. Pharmacokinetic parameters were calculated from individual concentration time curves. In all 12 subjects a significant increase was noted in plasma values of DG and CS after intake of maqui berry extract. Maximum concentration of DG was observed after 1.0 ± 0.3 h and CS after 2.0 ± 1.1 h. Within 8 h, concentrations nearly returned to baseline levels. The results confirm a fast uptake and metabolism of the two selected key substances. Additionally, the phenolic acids GA and PCA were observed as breakdown products of anthocyanins. In summary, the study clearly confirms the bioavailability of maqui berry extract and its specific anthocyanin compounds and related breakdown products in healthy subjects.

Effect of consumption of chicory inulin on bowel function in healthy subjects with constipation: a randomized, double-blind, placebo-controlled trial.

Constipation is among the most common health impairments in Western countries. This study aimed to determine the effect of the chicory-derived fermentable dietary fiber Orafti® Inulin on stool frequency in healthy subjects with constipation. The study was conducted according to recent guidance documents for investigating bowel function and used a randomized, double-blind, placebo-controlled, cross-over design with a 2-week wash-out phase. Each study period comprised a run-in phase followed by 4 weeks daily intake of 3 × 4g inulin or maltodextrin (placebo). Forty-four healthy volunteers with constipation documented stool frequency and consistency, gastrointestinal characteristics and quality of life. Consumption of Orafti® Inulin significantly increased stool frequency compared to placebo (median 4.0 [IQR 2.5-4.5] versus 3.0 [IQR 2.5-4.0] stools/week, p = 0.038). This was accompanied by a softening of stools and trend toward higher satisfaction versus placebo (p = 0.059). In conclusion, Orafti® Inulin was effective in volunteers with chronic constipation and significantly improved bowel function. CLINICAL TRIAL REGISTRATION: This trial was registered at clinicaltrials.gov as NCT02548247.