Re: Consumption of Maslinic Acid from Olive Fruit Improves Knee Pain and Quality of Life and Promotes Weight Loss

Olive (Olea europaea, Oleaceae) Maslinic Acid Knee Pain Date: 08-31-2017 HC# 011738-575 Fukumitsu S, Villareal MO, Aida K, et al. Maslinic acid in olive fruit alleviates mild knee joint pain and improves quality of life by promoting weight loss in the elderly. J Clin Biochem Nutr. 2016;59(3):220-225. Consumption of olive (Olea europaea, Oleaceae) oil and olives is associated with a low incidence of inflammation-related diseases. Olive pomace, a byproduct of olive oil extraction consisting of olive flesh, skin, and seeds, is a rich source of pentacyclic triterpenes, mainly maslinic acid (MA). MA has been found to possess several biological and therapeutic properties against diseases and, in a previous study by the authors, it demonstrated anti-inflammatory and antiarthritic action. The goal of this randomized, double-blind, placebo-controlled trial was to investigate the effects of an MA-containing olive fruit extract supplement on mild knee pain in middle-aged and elderly subjects. The study was conducted at Sakura Clinic of the Medical Corporation in Tokyo, Japan, from May 2014 to October 2014. Its primary outcomes were spontaneous pain as measured on a visual analogue scale (VAS) and general quality of life (QOL) as assessed on the Short Form-8 Health Survey (SF-8). Secondary outcomes included the measurement of body composition and serum biomarkers associated with cartilage metabolism and joint inflammation, as well as the safety of consuming MA daily. Eligible subjects were men or women aged 40 to 75 years suffering from knee pain when ascending or descending stairs and diagnosed with a slight degree of knee arthritis. The subjects consumed either placebo capsules or capsules containing 50 mg MA (500 mg as olive fruit extract) once daily for 12 weeks. The subjects were instructed to record daily whether they took the capsule during breakfast, their general physical condition, and the degree of knee pain. The olive fruit extract contained 10.7% MA, 57% gamma-cyclodextrin, 22.8% protein, 1.5% fat, 2.5% ash, 3.4% moisture, and other minor components such as oleanolic acid. The MA capsules contained olive fruit extract, calcium stearate, and 16.7 mg MA. The placebo capsules were identical in color and size and contained corn (Zea mays, Poaceae) starch instead of olive fruit extract. Twenty subjects were randomly assigned to the olive fruit extract group (n=12) or the placebo group (n=8). The subjects completed the VAS and SF-8 at baseline and at weeks 8 and 12. The secondary outcome measures were obtained at baseline and after 12 weeks, using body composition and blood parameters such as high-sensitivity C-reactive protein (hs-CRP) to indicate inflammation and N-propeptide of collagen IIA (PIIANP) and collagen type II cleavage (C2C) to assess cartilage turnover. All 20 subjects completed the study. Subjects in both groups reported a decrease of pain on the VAS at the end of the study compared with baseline; pain decreased by 56% in the MA group (P=0.00002) and by 51% in the placebo group (P=0.002). The between-group differences were not significant. As shown on the SF-8, QOL improved in both groups, but slightly more so in the MA group. After 12 weeks, the MA group reported 117% improvement in QOL as indicated by the physical component summaries (P=0.0005) vs. 115% improvement in the placebo group (P=0.014). Both groups exhibited improved QOL based on the mental component summaries at weeks 8 and 12 compared with baseline, with the MA group exhibiting slightly more improved symptoms compared with those of the placebo group at the end of the study. The MA group experienced significantly decreased body weight (P=0.019) and body mass index (P=0.019) in subjects with mild joint pain at week 12 compared with baseline. No significant changes were seen in the placebo group. No significant changes were seen in hs-CRP, PIIANP, C2C, or C2C/PIIANP levels in either group during the 12 weeks compared with baseline, and no between-group differences were reported. And yet, the MA group did have a 15.2% decrease in level of serum hs-CRP, while the placebo group experienced an 11.8% increase. "Based on these findings, MA is most likely to improve joint condition and QOL by reducing pain and inflammatory response in this study," write the authors. No significant changes were seen in blood parameters, indicating the safety of the intervention, and no adverse effects due to the intake of MA were reported. Earlier studies report that MA prevents bone loss1 and that cartilage turnover is slow in elderly persons and at the onset of osteoarthritis.2,3 In this study, the differences in serum PIIANP levels were not statistically significant in the groups after 12 weeks compared with those of baseline; however, at the end of the study, the values reflected a 6% increase in the MA group vs. a 1.3% decrease in the placebo group. The average levels of serum C2C before and after MA or placebo intake were both increased but not significantly. The ratio of C2C/PIIANP (the ratio of degradation and synthesis of joint cartilage) was similar between the 2 groups after treatment compared with baseline. Because of this, the authors "consider that olive fruit MA likely regulates and activates cartilage turnover but further investigation with long-term use of MA will be needed to confirm the direct effects of MA on joint cartilage as well as determine the effective dose when consumed daily." The results of this study suggest that the consumption of MA in olive fruit may improve joint pain and the physical components of QOL, as well as promote weight loss. As such, olive products containing MA may be useful as a therapeutic food ingredient for arthritic diseases. Admitted limitations include the small number of healthy subjects enrolled and the authors suggest that the beneficial effects of MA shown in this study should be verified in a larger cohort of patients with osteoarthritis. Three of the authors (Fukumitsu, Aida, and Hino) are employees of Nippon Flour Mills Co., Ltd. (Atsugi, Kanagawa, Japan), a company that is involved in the research and manufacture of functional ingredients and food products. ―Shari Henson References 1Li C, Yang Z, Li Z, et al. Maslinic acid suppresses osteoclastogenesis and prevents ovariectomy-induced bone loss by regulating RANKL-mediated NF-ĸB and MAPK signaling pathways. J Bone Miner Res. 2011;26(3):644-656. 2DeGroot J, Verzijl N, Bank RA, Lafeber FP, Bijlsma JW, TeKoppele JM. Age-related decrease in proteoglycan synthesis of human articular chondrocytes: the role of nonenzymatic glycation. Arthritis Rheum. 1999;42(5):1003-1009. 3DeGroot J, Verzijl N, Wenting-van Wijk MJ, et al. Accumulation of advanced glycation end products as a molecular mechanism for aging as a risk factor in osteoarthritis. Arthritis Rheum. 2004;50(4):1207-1215.