Laurent Ameye

Osteoarthritis and nutrition. From nutraceuticals to functional foods: a systematic review of the scientific evidence

The scientific and medical community remains skeptical regarding the efficacy of nutrition for osteoarthritis despite their broad acceptation by patients. In this context, this paper systematically reviews human clinical trials evaluating the effects of nutritional compounds on osteoarthritis. We searched the Medline, Embase, and Biosis databases from their inception to September 2005 using the terms random, double-blind method, trial, study, placebo, and osteoarthritis. We selected all peer-reviewed articles reporting the results of randomised human clinical trials (RCTs) in osteoarthritis that investigated the effects of oral interventions based on natural molecules. Studies on glucosamine and chondroitin sulfate were excluded. The quality of the RCTs was assessed with an osteoarthritic-specific standardised set of 12 criteria and a validated instrument. A best-evidence synthesis was used to categorise the scientific evidence behind each nutritional compound as good, moderate, or limited. A summary of the most relevant in vitro and animal studies is used to shed light on the potential mechanisms of action. Inclusion criteria were met by 53 RCTs out of the 2,026 identified studies. Good evidence was found for avocado soybean unsaponifiables. Moderate evidence was found for methylsulfonylmethane and SKI306X, a cocktail of plant extracts. Limited evidence was found for the Chinese plant extract Duhuo Jisheng Wan, cetyl myristoleate, lipids from green-lipped mussels, and plant extracts from Harpagophytum procumbens. Overall, scientific evidence exists for some specific nutritional interventions to provide symptom relief to osteoarthritic patients. It remains to be investigated whether nutritional compounds can have structure-modifying effects.

Targeted Disruption of Two Small Leucine-rich Proteoglycans, Biglycan and Decorin, Excerpts Divergent Effects on Enamel and Dentin Formation

Small leucine-rich proteoglycans have been suggested to affect mineralization of dental hard tissues. To determine the functions of two of these small proteoglycans during the early stages of tooth formation, we characterized the dental phenotypes of biglycan (BGN KO) and decorin deficient (DCN KO) mice and compared them to that of wild type mice. Each targeted gene disruption resulted in specific effects on dentin and enamel formation. Dentin was hypomineralized in both knock out mice, although the effect was more prominent in the absence of decorin. Enamel formation was dramatically increased in newborn biglycan knockout mice but delayed in absence of decorin. Increased enamel formation in the former case resulted from an upregulation of amelogenin synthesis whereas delayed enamel formation in the later case was most probably an indirect consequence of the high porosity of the underlying dentin. Enamelin expression was unchanged in BGN KO, and reduced in DCN KO. Dentin sialoprotein (DSP), a member of the family of phosphorylated extracellular matrix proteins that play a role in dentinogenesis, was overexpressed in BGN-KO odontoblasts and in the sub-odontoblastic layer. In contrast, a decreased expression of DSP was detected in DCN KO. Dentin matrix protein-1 (DMP-1), bone sialoprotein (BSP) and osteopontin (OPN) were upregulated in BGN KO and downregulated in the DCN KO. Despite the strong effects induced by these deficiencies in newborn mice, no significant difference was detected between the three genotypes in adult mice, suggesting that the effects reported here in newborn mice are transient and subjected to self-repair.

Mice Deficient in Biglycan and Fibromodulin as a Model for Temporomandibular Joint Osteoarthritis

The temporomandibular joint (TMJ) within the craniofacial complex is unique. In humans, the TMJ can become diseased resulting in severe and disabling pain. There are no cures for TMJ disease at this time. Animal models of TMJ disease are scarce, but some exist, and they are described in this paper. We present in greater detail one animal model that is deficient in two extracellular matrix (ECM) proteoglycans, biglycan (BGN) and fibromodulin (FMOD). Doubly deficient BGN/FMOD mice develop premature TMJ osteoarthritis (OA). In order to explore the mechanistic basis of TMJ-OA, tissues from the condyle of mutant mice were examined for their relative capacity to differentiate and undergo apoptosis. Our data show that there is a redistribution of the critical ECM protein, type II collagen, in mutant mice compared with controls. Mutant mice also have increased apoptosis of the chondrocytes embedded in the articular cartilage. We speculate that the overall imbalance in apoptosis may be the cellular basis for the abnormal production of structural ECM proteins. The abnormal production of the ECM could, in turn, lead to premature erosion and degradation of the articular surface resulting in TMJ-OA. These data underscore the importance of the ECM in controlling the structural integrity of the TMJ.

Fibromodulin-Deficient Mice Reveal Dual Functions for Fibromodulin in Regulating Dental Tissue and Alveolar Bone Formation

The extracellular matrix of newborn, 7- and 21-day-old fibromodulin-deficient (Fmod KO) mice was compared with age-matched wild-type (WT) mice. Western blotting of proteins from 21-day-old WT mice revealed that the molecular weight of Fmod is smaller in dental tissues (approx. 40 kDa) compared to alveolar bone extracts (approx. 52 kDa). Dentin matrix protein1 (DMP1) was slightly increased in Fmod KO versus WT tooth extracts. After chondroitinase ABC digestion, dentin sialophosphoprotein (DSPP) appeared as 2 strong bands (approx. 150 and 70 kDa) in incisors from 21-day-old Fmod KO mice, whereas the smaller-sized species of DSPP was nearly absent in WT molars and no difference was detected between WT and KO mice in molars. Dentin mineralization was altered in newborn and 7-day-old KO mice, but seemed normal in 21-day-old KO mice. DMP1 and DSPP may be involved in compensatory mechanisms. The enamel had a twisted appearance and looked porous at day 21 in KO incisor, and the outer aprismatic layer was missing in the molar. Alveolar bone formation was enhanced in Fmod KO mice at days 0 and 7, whereas no difference was detected at day 21. We conclude that Fmod may control dental tissue formation and early maturation, where it acts mostly as an inhibitor in alveolar bone accumulation, excerpting its effects only at early developing stages. These dual functions may be related to the different forms of Fmod found in bone versus teeth.

Carnosol Inhibits Pro-Inflammatory and Catabolic Mediators of Cartilage Breakdown in Human Osteoarthritic Chondrocytes and Mediates Cross-Talk between Subchondral Bone Osteoblasts and Chondrocytes.

Aim The aim of this work was to evaluate the effects of carnosol, a rosemary polyphenol, on pro-inflammatory and catabolic mediators of cartilage breakdown in chondrocytes and via bone-cartilage crosstalk. Materials and Methods Osteoarthritic (OA) human chondrocytes were cultured in alginate beads for 4 days in presence or absence of carnosol (6 nM to 9 μM). The production of aggrecan, matrix metalloproteinase (MMP)-3, tissue inhibitor of metalloproteinase (TIMP)-1, interleukin (IL)-6 and nitric oxide (NO) and the expression of type II collagen and ADAMTS-4 and -5 were analyzed. Human osteoblasts from sclerotic (SC) or non-sclerotic (NSC) subchondral bone were cultured for 3 days in presence or absence of carnosol before co-culture with chondrocytes. Chondrocyte gene expression was analyzed after 4 days of co-culture. Results In chondrocytes, type II collagen expression was significantly enhanced in the presence of 3 μM carnosol (p = 0.008). MMP-3, IL-6, NO production and ADAMTS-4 expression were down-regulated in a concentration-dependent manner by carnosol (p<0.01). TIMP-1 production was slightly increased at 3 μM (p = 0.02) and ADAMTS-5 expression was decreased from 0.2 to 9 μM carnosol (p<0.05). IL-6 and PGE2 production was reduced in the presence of carnosol in both SC and NSC osteoblasts while alkaline phosphatase activity was not changed. In co-culture experiments preincubation of NSC and SC osteoblasts wih carnosol resulted in similar effects to incubation with anti-IL-6 antibody, namely a significant increase in aggrecan and decrease in MMP-3, ADAMTS-4 and -5 gene expression by chondrocytes. Conclusions Carnosol showed potent inhibition of pro-inflammatory and catabolic mediators of cartilage breakdown in chondrocytes. Inhibition of matrix degradation and enhancement of formation was observed in chondrocytes cocultured with subchondral osteoblasts preincubated with carnosol indicating a cross-talk between these two cellular compartments, potentially mediated via inhibition of IL-6 in osteoblasts as similar results were obtained with anti-IL-6 antibody.

Growth and Nutritional Biomarkers of Preterm Infants Fed a New Powdered Human Milk Fortifier: A Randomized Trial

Objectives: The aim of this study was to assess growth and nutritional biomarkers of preterm infants fed human milk (HM) supplemented with a new powdered HM fortifier (nHMF) or a control HM fortifier (cHMF). The nHMF provides similar energy content, 16% more protein (partially hydrolyzed whey), and higher micronutrient levels than the cHMF, along with medium-chain triglycerides and docosahexaenoic acid. Methods: In this controlled, multicenter, double-blind study, a sample of preterm infants ⩽32 weeks or ⩽1500 g were randomized to receive nHMF (n = 77) or cHMF (n = 76) for a minimum of 21 days. Weight gain was evaluated for noninferiority (margin = –1 g/day) and superiority (margin = 0 g/day). Nutritional status and gut inflammation were assessed by blood, urine, and fecal biochemistries. Adverse events were monitored. Results: Adjusted mean weight gain (analysis of covariance) was 2.3 g/day greater in nHMF versus cHMF; the lower limit of the 95% CI (0.4 g/day) exceeded both noninferiority (P < 0.001) and superiority margins (P = 0.01). Weight gain rate (unadjusted) was 18.3 (nHMF) and 16.8 g · kg−1 · day−1 (cHMF) between study days 1 and 21 (D1–D21). Length and head circumference (HC) gains between D1 and D21 were not different. Adjusted weight-for-age z score at D21 and HC-for-age z score at week 40 corrected age were greater in nHMF versus cHMF (P = 0.013, P = 0.003 respectively). nHMF had higher serum blood urea nitrogen, pre-albumin, alkaline phosphatase, and calcium (all within normal ranges; all P ⩽ 0.019) at D21 versus cHMF. Both HMFs were well tolerated with similar incidence of gastrointestinal adverse events. Conclusions: nHMF providing more protein and fat compared to a control fortifier is safe, well-tolerated, and improves the weight gain of preterm infants.

071 EFFECT OF ROSEMARY EXTRACT AND RELATED FLAVONOID CARNOSOL ON CHONDRO-PROTECTION AND ON THE BONE-CARTILAGE CROSSTALK

whose blood expression was altered compared to healthy subjects. In OA, 9 miRNA were up-regulated (including miR-228, miR-574-3p, miR-597) and 9 miRNAs were down-regulated (including miR-150, miR-222, miR-363 and miR-423). None of miRNAs in OA is common with those we found in RA. Potential targets of miRNAs, specifically expressed in severe knee osteoarthritis, appears to be largely involved in the Wnt signaling pathway. In contrast, the miRNAs expressed differently in the blood of our RA patients seem to target the elements of the signaling pathway MAP kinase. Conclusions: Our results suggest that miRNAs may constitute new biomarkers potential diagnostic interest. In addition, miRNAs could be involved in the pathogenesis of OA. Further work is ongoing in order to assess the pathophysiological and the functional role of these miRNAs in OA.

Effects on Fatty Acid Metabolism of a New Powdered Human Milk Fortifier Containing Medium-Chain Triacylglycerols and Docosahexaenoic Acid in Preterm Infants

Preterm infants require fortification of human milk (HM) with essential fatty acids (FA) to ensure adequate post-natal development. As part of a larger randomized controlled study, we investigated FA metabolism in a subset of 47 clinically stable preterm infants (birth weight ≤1500 g or gestational age ≤32 weeks). Infants were randomized to receive HM supplemented with either a new HM fortifier (nHMF; n = 26) containing 12.5 g medium-chain FA (MCFA), 958 mg linoleic acid (LA), 417 mg α-linolenic acid (ALA), and 157 mg docosahexaenoic acid (DHA) per 100 g of powder (in compliance with the latest guidelines) or a fat-free HMF (cHMF; n = 21). Plasma phospholipid (PL) and triacylglycerol (TAG), and red blood cell phosphatidylcholine (RBC-PC) and phosphatidylethanolamine (RBC-PE) FA profiles were assessed before and after 21 days of feeding. In the nHMF group, significantly increased levels of n-9 monounsaturated fatty acids were observed, formed most likely by elongation and desaturation of dietary saturated fatty acids present in HM. ALA fortification increased ALA assimilation into plasma TAG. Similarly, DHA fortification enriched the DHA content in RBC-PE, which, in this compartment, was not associated with lower arachidonic acid levels as observed in plasma TAG and phospholipids. RBC-PE, a reliable indicator of FA metabolism and accretion, was the most sensitive compartment in this study.

176 CHICORY EXTRACTS AND THEIR 3 MAJOR SESQUITERPENE LACTONES INHIBIT GLYCOSAMINOGLYCAN DEGRADATION AND NITRIC OXIDE PRODUCTION IN BOVINE ARTICULAR CARTILAGE EXPLANTS

of c-jun N terminal kinase (JNK), p38 MAP kinase and extracellular-signal regulated kinase (ERK)-1/2. GlcN inhibited JNK and p38 phosphorylation and consequently c-jun and to a lower degree junD DNA binding activity. Moreover, we found also down-regulation of c-jun mRNA transcription level. Conclusions: These results demonstrated for the first time, in human chondrocytes, that GlcN inhibits cytokine-stimulated MMP production, by affecting MAP kinase phosphorylation and consequently AP-1 transcription factor.