Search

Background/Objectives : Marine collagen peptides (MCPs) and glycosaminoglycans (GAGs) have been described as potential wound-healing (WH) agents. Fish cartilage hydrolysate (FCH) is a natural active food ingredient obtained from enzymatic hydrolysis which combines MCPs and GAGs. Recently, the clinical benefits of FCH supplementation for the skin, as well as its mode of action, have been demonstrated. Some of the highlighted mechanisms are common to the WH process. The aim of the study is therefore to investigate the influence of FCH supplementation on the skin healing processes and the underlying mechanisms. Methods : To this end, an ex vivo clinical approach, which takes into account the clinical digestive course of nutrients, coupled with primary cell culture on human dermal fibroblasts (HDFs) and ultra-deep proteomic analysis, was performed. The effects of human serum enriched in circulating metabolites resulting from FCH ingestion (FCH-enriched serum) were assessed on HDF WH via an in vitro scratch wound assay and on the HDF proteome via diaPASEF (Data Independent Acquisition-Parallel Accumulation Serial Fragmentation) proteomic analysis. Results : Results showed that FCH-enriched human serum accelerated wound closure. In support, proteins with anti-inflammatory and immunomodulatory properties and proteins prone to promote hydration and ECM stability showed increased expression in HDFs after exposure to FCH-enriched serum. Conclusions : Taken together, these data provide valuable new insights into the mechanisms that may contribute to FCH's beneficial impact on human skin functionality by supporting WH. Further studies are needed to reinforce these preliminary data and investigate the anti-inflammatory and immunomodulatory properties of FCH.

Safe and anti-inflammatory plant-based natural products present an increasing focus in the treatment of chronic inflammatory diseases such as osteoarthritis or inflammatory bowel diseases. Among them, saffron, a spice derived from the stigma of Crocus sativus, could have anti-inflammatory properties and would be therefore a promising therapeutic agent for the treatment of such conditions. However, the anti-inflammatory molecular mechanisms of saffron in humans are still understudied and unclear. In this study, combining human serum metabolites and cell cultures, we evaluated the effect of circulating metabolites from the consumption of a patented saffron extract (Safr'Inside TM ) on the chondrocytes and colon epithelial cell responses to inflammatory stress. Parametric or non-parametric Analysis of Variance with post hoc tests was performed. We demonstrated that human serum containing metabolites from saffron intake attenuated IL-1β-stimulated production of PGE2 and MMP-13 in chondrocyte cells and limited the increase in ICAM-1, MCP-1, iNOS, and MMP-3 in human epithelial cells following combined IL-1β and TNF-α inflammatory stimulation. Altogether, these data provide new findings into the mechanisms underlying the beneficial effects of saffron on chondrocytes and enterocyte cells at the cellular level and in the context of chronic inflammatory disorders.

Background: Aging is frequently associated with impairments of the musculoskeletal system and many elderly people experience joint discomfort or pain which might reduce their ability to move and consequently alter their quality of life. A beneficial effect of fish cartilage hydrolysate (FCH) on pain and joint function has recently been shown in an ACLT/pMMx osteoarthritis rat model., Methods: We therefore performed an exploratory, non-comparative, multi-centric clinical trial including 33 subjects with moderate knee joint discomfort and loss of functionality to investigate the efficacy of FCH on their algo-functional status. We further determined the potential health benefit of FCH in an original clinical ex vivo study investigating the role of FCH human metabolites on primary human chondrocytes., Results: FCH significantly improved knee pain and function, as assessed by the Knee injury and Osteoarthritis Outcome Score (KOOS). Moreover, FCH significantly reduced pain at rest and while walking, and patient global assessment (PGA), as assessed by the Visual Analogue Scale (VAS), and improved patients' quality of life (SF-36). FCH metabolites decreased the synthesis of catabolic factors (MMP-13) and pro-inflammatory mediators (NO, PGE2) and limited the inhibitory effect of IL-1β on the synthesis of cartilage matrix components (GAG and collagen)., Conclusions: Thus, these data provide insights on the mode of action of FCH in humans and contribute to explain how FCH may relieve pain and improve joint function in subjects with knee discomfort. Although these preliminary data need to be confirmed in a randomized controlled trial, they strongly support the potential health benefit of such an active ingredient., Trial Registration: The study was registered on clinicaltrials.gov with the identifier NCT04420091 (09/06/2020)., (© 2023. BioMed Central Ltd., part of Springer Nature.)

TOTUM-070 is a patented polyphenol-rich blend of five different plant extracts showing separately a latent effect on lipid metabolism and potential synergistic properties. In this study, we investigated the health benefit of such a formula. Using a preclinical model of high fat diet, TOTUM-070 (3 g/kg of body weight) limited the HFD-induced hyperlipemia with a reduction in triglyceride (-32% after 6 weeks; -20.3% after 12 weeks) and non-HDL cholesterol levels (-21% after 6 weeks; -38.4% after 12 weeks). To further investigate such a benefit and its underlying mechanisms in humans, we designed an ex vivo clinical approach to collect the circulating bioactives resulting from TOTUM-070 ingestion and to determine their biological activities on human hepatocytes. Human serum was obtained from healthy subjects before and after intake of TOTUM-070 (4995 mg). The presence of circulating metabolites was assessed by UPLC-MS/MS. Serum containing metabolites was further incubated with hepatocytes cultured in a lipotoxic environment (palmitate, 250 µM). RNA sequencing analyses show that lipid metabolism was one of the most impacted processes. Using histologic, proteomic, and enzymatic assays, the effects of human TOTUM-070 bioactives on hepatocyte metabolism were characterized by (1) the inhibition of lipid storage, including both (2) triglycerides (-41%, p < 0.001) and (3) cholesterol (-50%, p < 0.001) intracellular content, (4) a reduced de novo cholesterol synthesis (HMG-CoA reductase activity -44%, p < 0.001), and (5) a lowered fatty acid synthase protein level ( p < 0.001). Altogether, these data support the beneficial impact of TOTUM-070 on lipid metabolism and provide new biochemical insights in human mechanisms occurring in liver cells.

Impairment of gut function is one of the explanatory mechanisms of health status decline in elderly population. These impairments involve a decline in gut digestive physiology, metabolism and immune status, and associated to that, changes in composition and function of the microbiota it harbors. Continuous deteriorations are generally associated with the development of systemic dysregulations and ultimately pathologies that can worsen the initial health status of individuals. All these alterations observed at the gut level can then constitute a wide range of potential targets for development of nutritional strategies that can impact gut tissue or associated microbiota pattern. This can be key, in a preventive manner, to limit gut functionality decline, or in a curative way to help maintaining optimum nutrients bioavailability in a context on increased requirements, as frequently observed in pathological situations. The aim of this review is to give an overview on the alterations that can occur in the gut during aging and lead to the development of altered function in other tissues and organs, ultimately leading to the development of pathologies. Subsequently is discussed how nutritional strategies that target gut tissue and gut microbiota can help to avoid or delay the occurrence of aging-related pathologies.

Due to its significant exposure to stressful environmental factors, the skin undergoes a high remodeling rate over time, which alters not only its appearance but also its functionality. This alteration of the skin, namely photoaging, is characterized by dryness and a loss of elasticity that mainly originates from the dysregulation of dermal fibroblast activities. In order to overcome such tissue outcome, cosmetic products have evolved toward nutricosmetics, thus promoting beauty from within. Among bio-actives of interest, bio-peptides deriving from plant or animal sources may exert various biological activities beyond their nutritional value. However, studies remain mostly descriptive and the mode of action at the cellular level in clinic remains a concern. In a recent clinical trial, it was showed that supplementation with a fish cartilage hydrolysate (FCH) improved signs of chronological and photoaging-induced skin changes in healthy women. Here, using an original ex vivo clinical approach adapted to nutricosmetic purpose, we further demonstrated that this fish cartilage hydrolysate was absorbed and that the circulating metabolites produced in humans following FCH intake stimulate human dermal fibroblast growth, promote specific hyaluronan production, up-regulate elastin synthesis and inhibit MMP-1 and 3 expression along with the enhancement of TGF-β release. Altogether, these data provide clues on the mechanisms likely contributing to the beneficial impact of FCH on human skin functionality by supporting hydration, elasticity and limiting the expression of catabolic factors involved in photoaging onset.

Allograft bone tissue has a long history of use. There are two main ways of preserving allografts: by cold (freezing), or at room temperature after an additional cleaning treatment using chemicals. These chemicals are considered potentially harmful to humans. The aim of the study was (i) to assess the presence of chemical residues on processed bone allografts and (ii) to compare the in vitro biocompatibility of such allografts with that of frozen allografts. The presence of chemical residues on industrially chemically treated bone was assessed by high performance liquid chromatography (HPLC) after extraction. Biocompatibility analysis was performed on primary osteoblast cultures from Wistar rats grown on bone disks, either frozen (F-bone group) or treated with supercritical carbon dioxide with no added chemical (scCO2-bone group) or industrially treated with chemicals (CT-bone group). Cell viability (XTT) was measured after one week of culture. Osteoblastic differentiation was assessed after 1, 7 and 14 days of culture by measuring alkaline phosphatase (ALP) activity directly on the bone discs and indirectly on the cell mat in the vicinity of the bone discs. Residues of all the chemicals used were found in the CT-bone group. There was no significant difference in cell viability between the three bone groups. Direct and indirect ALP activities were significantly lower (-40% to -80%) in the CT-bone group after 7 and 14 days of culture (p < 0.05). Residues of chemical substances used in the cleaning of bone allografts cause an in vitro decrease in their biocompatibility. Tissue cleaning processes must be developed that limit or replace these chemicals to favor biocompatibility., Competing Interests: Authors GV, RE, SD, and SB have made a Declaration of Invention regarding the specific cleaning process using supercritical carbon dioxide described in this study. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

Treating large bone defects or fragile patients may require enhancing the bone regeneration rate to overcome a weak contribution from the body. This work investigates the osteogenic potential of nutrient fisetin, a flavonoid found in fruits and vegetables, as a doping agent inside the structure of a SiO 2 -CaO bioactive glass-poly(caprolactone) (BG-PCL) hybrid scaffold. Embedded in the full mass of the BG-PCL hybrid during one-pot synthesis, we demonstrate fisetin to be delivered sustainably; the release follows a first-order kinetics with active fisetin concentration being delivered for more than 1 month (36 days). The biological effect of BG-PCL-fisetin-doped scaffolds (BG-PCL-Fis) has been highlighted by in vitro and in vivo studies. A positive impact is demonstrated on the adhesion and the differentiation of rat primary osteoblasts, without an adverse cytotoxic effect. Implantation in critical-size mouse calvaria defects shows bone remodeling characteristics and remarkable enhancement of bone regeneration for fisetin-doped scaffolds, with the regenerated bone volume being twofold that of nondoped scaffolds and fourfold that of a commercial trabecular bovine bone substitute. Such highly bioactive materials could stand as competitive alternative strategies involving biomaterials loaded with growth factors, the use of the latter being the subject of growing concerns., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

The treatment of osteomyelitis, a destructive inflammatory process caused by bacterial infections to bone tissue, is one of the most critical challenges of orthopedics and bone regenerative medicine. The standard treatment consists of intense antibiotic therapies combined with tissue surgical debridement and the application of a bone defect filler material. Unfortunately, commercially available candidates, such as gentamicin-impregnated polymethylmethacrylate cements, possess very poor pharmacokinetics ( i.e. , 24 hours burst release) and little to no regenerative potential. Fostered by the intrinsic limitations associated with conventional treatments, alternative osteostimulative biomaterials with local drug delivery have recently started to emerge. In this study, we propose the use of a polycaprolactone-silica sol-gel hybrid material as carrier for the delivery of rifampicin, an RNA-polymerase blocker often used to treat bone infections, and of osteostimulative silicate ions. The release of therapeutic agents from the material is dual, offering two separate and simultaneous effects, and decoupled, meaning that the kinetics of rifampicin and silicate releases are independent from each other. A series of hybrid formulations with increasing amounts of rifampicin was prepared. The antibiotic loading efficacy, as well as the release profiles of rifampicin and silicates were measured. The characterization of cell viability and differentiation of rat primary osteoblasts and antibacterial performance were also performed. Gram-positive Staphylococcus aureus and Gram-negative Pseudomonas aeruginosa and Escherichia coli were selected due to their high occurrence in bone infections. Results confirmed that rifampicin can be successfully loaded within the hybrids without significant degradation and that it is possible to tailor the antibiotic release according to need. Once in a physiological environment, the rapid release of silicates was associated with optimal cell proliferation and the overexpression of osteoblastic differentiation. Simultaneously, rifampicin is delivered over the course of several weeks with significant inhibition of all tested strains. In particular, the materials caused a growth reduction of 7-10 orders of magnitude in Staphylococcus aureus , the major strain responsible for osteomyelitis worldwide. Our data strongly suggest that PCL/silica hybrids are a very promising candidate to develop bone fillers with superior biological performance compared to currently available options. Thanks to their unique synthesis route and their dual tailored release they can promote bone regeneration while reducing the risk of infection for several weeks upon implantation.

Increases in oxidative stress have been reported to play a central role in the vulnerability to depression, and antidepressant drugs may reduce increased oxidative stress in patients. Among the plants exerting anti-inflammatory and anti-oxidant properties, saffron, a spice derived from the flower of Crocus sativus , is also known for its positive effects on depression, potentially through its SSRI-like properties. However, the molecular mechanisms underlying these effects and their health benefits for humans are currently unclear. Using an original ex vivo clinical approach, we demonstrated for the first time that the circulating human metabolites produced following saffron intake (Safr'Inside TM ) protect human neurons from oxidative-stress-induced neurotoxicity by preserving cell viability and increasing BNDF production. In particular, the metabolites significantly stimulated both dopamine and serotonin release. In addition, the saffron's metabolites were also able to protect serotonergic tone by inhibiting the expression of the serotonin transporter SERT and down-regulating serotonin metabolism. Altogether, these data provide new biochemical insights into the mechanisms underlying the beneficial impact of saffron on neuronal viability and activity in humans, in the context of oxidative stress related to depression.

Among postmenopausal women with estrogen receptor-positive breast cancer, more than 80% receive hormone therapy including aromatase inhibitors (AIs). Half of them develop chronic arthralgia - characterized by symmetric articular pain, carpal tunnel syndrome, morning stiffness, myalgia and a decrease in grip strength - which is associated with treatment discontinuation. Only a few animal studies have linked AI treatment to nociception, and none to arthralgia. Thus, we developed a new chronic AI-induced nociceptive disorder model mimicking clinical symptoms induced by AIs, using subcutaneous letrozole pellets in ovariectomized (OVX) rats. Following plasma letrozole dosage at the end of the experiment (day 73), only rats with at least 90 ng/ml of letrozole were considered significantly exposed to letrozole (OVX + high LTZ group), whereas treated animals with less than 90 ng/ml were pooled in the OVX + low LTZ group. Chronic nociceptive disorder set in rapidly and was maintained for more than 70 days in the OVX + high LTZ group. Furthermore, OVX + high LTZ rats saw no alteration in locomotion, myalgia or experimental anxiety during this period. Bone parameters of the femora were significantly altered in all OVX rats compared to Sham+vehicle pellet. A mechanistic analysis focused on TRPA1, receptor suspected to mediate AI-evoked pain, and showed no modification in its expression in the DRG. This new long-lasting chronic rat model, efficiently reproduces the symptoms of AI-induced nociceptive disorder affecting patients' daily activities and quality-of-life. It should help to study the pathophysiology of this disorder and to promote the development of new therapeutic strategies., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The aging of our population is accompanied by an increased prevalence of chronic diseases. Among those, liver, joint and adipose tissue-related pathologies have a major socio-economic impact. They share common origins as they result from a dysregulation of the inflammatory and metabolic status. Plant-derived nutrients and especially polyphenols, exert a large range of beneficial effects in the prevention of chronic diseases but require clinically validated approaches for optimized care management. In this study, we designed an innovative clinical approach considering the metabolites produced by the digestive tract following the ingestion of an artichoke leaf extract. Human serum, enriched with metabolites deriving from the extract, was collected and incubated with human hepatocytes, human primary chondrocytes and adipocytes to determine the biological activity of the extract. Changes in cellular behavior demonstrated that the artichoke leaf extract protects hepatocytes from lipotoxic stress, prevents adipocytes differentiation and hyperplasia, and exerts chondroprotective properties in an inflammatory context. These data validate the beneficial health properties of an artichoke leaf extract at the clinical level and provide both insights and further evidence that plant-derived nutrients and especially polyphenols from artichoke may represent a relevant alternative for nutritional strategies addressing chronic disease issues., Competing Interests: Fabien Wauquier and Line Wittrant-Boutin work for Clinic’n’Cell SAS (Faculty of Medicine and Pharmacy Clermont-Ferrand- France); Asma Boufarai-Aziez, Gwladys Charpentier, Emmanuel Cassin and Guillaume Rousselot work for Evear Extraction and provided the extracts. Laure Guilhaudis, Véronique Roux, Aurélien Viret, Nicolas Macian, Gisèle Pickering, Stéphane Descamps, Hassan Oulyadi and Yohann Wittrant have no conflict of interest to declare.

Protein hydrolysates are an important part of the human diet. Often, they are prepared from milk, soy, or collagen. In the present study, four different collagen hydrolysates were tested, varying in the average molecular weight and the animal source. Three types of samples, the dissolved start products, in vitro generated dialysates (containing the digested components that are potentially available for small intestinal absorption), and human serum collected after product ingestion, were analyzed using LC-MS to compare the state of the hydrolysates before and after absorption, i.e., uptake into the blood. It was found that the composition of the collagen hydrolysates prior to and after ingestion was highly complex and dynamic, which made it challenging to predefine a strategy for a targeted analysis. Therefore, we implemented a new analytical approach to first map hydrolysate data sets by performing non-targeted LC-MS analysis followed by non-targeted and targeted data analysis. It was shown that the insight gained by following such a top down (data) analytical workflow could be crucial for defining a suitable targeted setup and considering data trends beyond the defined targets. After having defined and performed a limited targeted analysis, it was found that, in our experimental setup, Hyp-Gly and especially Pro-Hyp contributed significantly as carrier to the total Hyp increase in blood after ingestion of collagen hydrolysate. Graphical abstract.

Rheumatoid arthritis (RA) has a negative impact on muscle mass, and reduces patient's mobility and autonomy. Furthermore, RA is associated with metabolic comorbidities, notably in lipid homeostasis by unknown mechanisms. To understand the links between the loss in muscle mass and the metabolic abnormalities, arthritis was induced in male Sprague Dawley rats (n = 11) using the collagen-induced arthritis model. Rats immunized with bovine type II collagen were compared to a control group of animals (n = 11) injected with acetic acid and complete Freund's adjuvant. The clinical severity of the ensuing arthritis was evaluated weekly by a semi-quantitative score. Skeletal muscles from the hind limb were used for the histological analysis and exploration of mitochondrial activity, lipid accumulation, metabolism and regenerative capacities. A significant atrophy in tibialis anterior muscle fibers was observed in the arthritic rats despite a non-significant decrease in the weight of the muscles. Despite moderate inflammation, accumulation of triglycerides (P < 0.05), reduced mitochondrial DNA copy number (P < 0.05) and non-significant dysfunction in mitochondrial cytochrome c oxidase activity were found in the gastrocnemius muscle. Concomitantly, our results suggested an activation of the muscle specific E3 ubiquitin ligases MuRF-1 and MAFbx. Finally, the adipose tissue from the arthritic rats exhibited decreased PPARγ mRNA suggesting reduced adipogenic capacities. In conclusion, the reduced adipose tissue adipogenic capacity and skeletal muscle mitochondrial capacity are probably involved in the activation of protein catabolism, inhibition of myogenesis, accumulation of lipids and fiber atrophy in the skeletal muscle during RA., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Polyphenols are widely acknowledged for their health benefits, especially for the prevention of inflammatory and age-related diseases. We previously demonstrated that hydroxytyrosol (HT) and procyanidins (PCy), alone or in combination, drive preventive anti-osteoathritic effects in vivo. However, the lack of sufficient clinical evidences on the relationship between dietary phytochemicals and osteoarthritis remains. In this light, we investigated in humans the potential osteoarticular benefit of a grapeseed and olive extract (OPCO) characterized for its hydroxytyrosol (HT) and procyanidins (PCy) content. We first validated, in vitro, the anti-inflammatory and chondroprotective properties of the extract on primary cultured human articular chondrocytes stimulated by interleukin-1 beta (IL-1 β). The sparing effect involved a molecular mechanism dependent on the nuclear transcription factor-kappa B (NF-κB) pathway. To confirm the clinical relevance of such a nutritional strategy, we designed an innovative clinical approach taking into account the metabolites that are formed during the digestion process and that appear in circulation after the ingestion of the OPCO extract. Blood samples from volunteers were collected following ingestion, absorption, and metabolization of the extract and then were processed and applied on human primary chondrocyte cultures. This original ex vivo methodology confirmed at a clinical level the chondroprotective properties previously observed in vitro and in vivo.

Calcium is an essential component of osteogenesis and is often required for imparting significant bioactivity to synthetic bone substitutes and, in particular, silicate-based materials. However, the mechanism of calcium incorporation inside sol-gel silicates is poorly understood. In this work, we shed light on the determinant parameters for incorporation of calcium into acid-base-catalyzed sol-gel silicates at ambient temperature: increasing the pH above the isoelectric point of silicic acid and the nature of the calcium counterion in the calcium precursor are found to be the key. Based on our proposed reaction sequence, we were able to compare calcium precursors and select an ideal candidate compound for the synthesis of bioactive glasses (BG) and organic-inorganic hybrids at ambient temperature. Reproducible syntheses and gel times of SiO 2 -CaO BG were obtained using calcium hydroxide (CH), and we demonstrate its usability in the synthesis of promising BG-polycaprolactone hybrid scaffolds. BG and hybrids prepared with CH were able to form nanocrystalline nonstoichiometric apatite in simulated body fluid. The increased reliability of low-temperature syntheses associated with the use of a stable and inexpensive alkaline-earth precursor are major steps toward the translation of calcium silicate hybrids or other alkaline-earth silicates from bench to clinic.

Purpose: Marrow adipose tissue (MAT) expansion and associated lipotoxicity are important drivers of age-related bone loss and hematopoietic bone marrow (HBM) atrophy. Fish oil and borage oil (rich in ω3 fatty acids) can partially prevent aged-related bone loss in SAMP8 mice. However, whether preservation of bone mass in this progeria model is associated with MAT volumes remains unknown. Results: MAT volume fraction (MAT%) showed a negative association with hematopoietic bone marrow (HBM%;r=-0.836, p <0.001) and bone (bone%;r=-0.344, p =0.013) volume fractions.Adjusting for multiple comparisons, bone% was higher and MAT% was lower in Fish oil (FO)-supplemented groups vs. controls ( p <0.001). HBM% did not differ significantly between the four groups. However, in the group supplemented with FO, HBM comprised higher fractions and MAT constituted lower fractions of total marrow vs. controls (p<0.001). Conclusion: Feeding FO-enriched diet prevented age-related bone and HBM loss, by reducing MAT expansion. Our results further emphasize on the role(s) of MAT expansion in bone and HBM atrophy. Methods: SAMP8 mice (n>9 /group) were allocated into 4 categories and fed a control ration, FO-, sunflower oil (SFO)- and borage oil-enriched diets for lifetime. Femurs were scanned using microcomputed tomography (μCT) and bone, MAT, and HBM volumes were determined using an image analysis software.

Organic-inorganic hybrid biomaterials stand as a promise for combining bone bonding and bone mineral-forming ability, stimulation of osteogenic cells, and adequate mechanical properties. Bioactive glass (BG)-polycaprolactone (PCL) hybrids are of special interest as they gather the ability of BG to enhance osteoblast-mediated bone formation with the slow degradation rate and the toughness of PCL. In this study, BG-PCL hybrids were synthesized in the form of scaffold, owing to a dual cortical/trabecular structure mimicking the bone architecture. Their biological potential was evaluated both in vitro using rat primary osteoblasts (RPO) and in vivo in a mice model of critical-size calvarial defects. BG-PCL scaffolds were compared to Lubboc (BTB), a commercial purified bovine xenograft widely used in orthopedics and periodontal procedures and known for its efficiency. BG-PCL hybrids were found to facilitate RPO adhesion at their surface and to enhance RPO differentiation when compared to BTB. An in vivo micro-CT study demonstrates a higher bone ingrowth with BG-PCL scaffolds and a complete chemical conversion of the remaining BG-PCL after 3 months of implantation, while histological data show the vascularization of BG-PCL scaffolds and confirm the well-advanced bone regeneration with ongoing remodeling. Finally, we evidence the complete chemical conversion of the remaining BG-PCL into a bone-like mineral.

Technological advances have provided surgeons with a wide range of biomaterials. Yet improvements are still to be made, especially for large bone defect treatment. Biomaterial scaffolds represent a promising alternative to autologous bone grafts but in spite of the numerous studies carried out on this subject, no biomaterial scaffold is yet completely satisfying. Bioactive glass (BAG) presents many qualifying characteristics but they are brittle and their combination with a plastic polymer appears essential to overcome this drawback. Recent advances have allowed the synthesis of organic-inorganic hybrid scaffolds combining the osteogenic properties of BAG and the plastic characteristics of polymers. Such biomaterials can now be obtained at room temperature allowing organic doping of the glass/polymer network for a homogeneous delivery of the doping agent. Despite these new avenues, further studies are required to highlight the biological properties of these materials and particularly their behavior once implanted in vivo. This review focuses on BAG with a particular interest in their combination with polymers to form organic-inorganic hybrids for the design of innovative graft strategies., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Collagen proteins are crucial components of the bone matrix. Since collagen-derived products are widely used in the food and supplement industry, one may raise the question whether collagen-enriched diets can provide benefits for the skeleton. In this study, we designed an innovative approach to investigate this question taking into account the metabolites that are formed by the digestive tract and appear in the circulation after ingestion of hydrolysed collagen. Blood samples collected in clinical and pre-clinical trials following ingestion and absorption of hydrolysed collagen were processed and applied on bone-related primary cell cultures. This original ex vivo methodology revealed that hydrolysed collagen-enriched serum had a direct impact on the behaviour of cells from both human and mouse origin that was not observed with controls (bovine serum albumin or hydrolysed casein-enriched serum). These ex vivo findings were fully in line with in vivo results obtained from a mouse model of post-menopausal osteoporosis. A significant reduction of bone loss was observed in mice supplemented with hydrolysed collagen compared to a control protein. Both the modulation of osteoblast and osteoclast activity observed upon incubation with human or mouse serum ex vivo and the attenuation of bone loss in vivo, clearly indicates that the benefits of hydrolysed collagen for osteoporosis prevention go beyond the effect of a simple protein supplementation., Competing Interests: Fabien Wauquier, Henri Granel, Audrey Daneault, Gael Rochefort, Jérome Guicheux, Adeline Blot, Nathalie Meunier and Yohann Wittrant have no conflict of interest to declare. Janne Prawitt and Véronique Fabien-Soulé work for Rousselot and provided the hydrolysed collagens.

Osteoporosis is a chronic and asymptomatic disease characterized by low bone mass and skeletal microarchitectural deterioration, increased risk of fracture, and associated comorbidities most prevalent in the elderly. Due to an increasingly aging population, osteoporosis has become a major health issue requiring innovative disease management. Proteins are important for bone by providing building blocks and by exerting specific regulatory function. This is why adequate protein intake plays a considerable role in both bone development and bone maintenance. More specifically, since an increase in the overall metabolism of collagen can lead to severe dysfunctions and a more fragile bone matrix and because orally administered collagen can be digested in the gut, cross the intestinal barrier, enter the circulation, and become available for metabolic processes in the target tissues, one may speculate that a collagen-enriched diet provides benefits for the skeleton. Collagen-derived products such as gelatin or hydrolyzed collagen (HC) are well acknowledged for their safety from a nutritional point of view; however, what is their impact on bone biology? In this manuscript, we critically review the evidence from literature for an effect of HC on bone tissues in order to determine whether HC may represent a relevant alternative in the design of future nutritional approaches to manage osteoporosis prevention.

Scope: The stimulation of the free fatty acid receptor G-protein coupled receptor (GPR) 40 by GW9508 prevents bone loss by inhibiting osteoclast activity, both in vitro and in vivo. Here, we questioned whether the stimulation of the GPR40 receptor by dietary fatty acids may lead to the same beneficial effect on bone., Methods and Results: We investigated (i) the impact of a fatty acid enriched diet (high-fat diet [HFD]) on bone health in C57/BL6 female mice depending on (ii) the estrogen status (ovariectomy) and (iii) the genotype (GPR40 +/+ or GPR40 -/- ). Bone mineral density (BMD), body composition, weight, inflammation and bone remodeling parameters were monitored. HFD decreased BMD in HFD-SH-GPR40 +/+ mice but OVX failed to further impact BMD in HFD-OVX-GPR40 +/+ mice, while additional bone loss was observed in HFD-OVX-GPR40 -/- animals. These data suggest that when stimulated by fatty acid enriched diets GPR40 contributes to counteract ovariectomy-induced bone alteration. The sparing effect is supported by the modulation of both the osteoprotegerin/receptor activator of nuclear factor kappa-B ligand (OPG/RANKL) ratio in blood stream and the expression level of inflammatory markers in adipose tissues. Bone preservation by GPR40 stimulation is dependent on the presence of long-chain saturated fatty acids., Conclusion: GPR40 contributes to counter ovariectomy-induced bone loss in a context of saturated fatty acid enrichment., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Purpose of Review: The design and the development of functional foods is a key issue for bone health and a scientific challenge as well. As most studies have focused on calcium, and have paid less attention to other nutrients, our knowledge of the influence of nutrition on bone health remains limited. It has been well acknowledged that the human diet contains a wide and complex range of bioactive molecules endowed with interesting protective properties. In this context, and according to their high content in micronutrients, a growing body of evidence has enlightened the high nutritional value of berries. This review addresses the emerging interest in berries for bone health., Recent Findings: Recent studies indicate that berry intakes are relevant to prevent osteopenia in humans. Their bone-sparing effects can be partly explained by their content in phytochemicals and vitamins. Beyond their antioxidant or anti-inflammatory functions, those micronutrients have been shown to modulate enzyme activities, cellular signaling pathways, and gene expression., Summary: Berry-enriched foods represent a relevant opportunity in the design of nutritional strategies targeting bone alteration.

Polyphenols exert a large range of beneficial effects in the prevention of age-related diseases. We sought to determine whether an extract of olive and grape seed standardized according to hydroxytyrosol (HT) and procyanidins (PCy) content, exerts preventive anti-osteoathritic effects. To this aim, we evaluated whether the HT/PCy mix could (i) have in vitro anti-inflammatory and chondroprotective actions, (ii) exert anti-osteoarthritis effects in two post-traumatic animal models and (iii) retain its bioactivity after oral administration. Anti-inflammatory and chondroprotective actions of HT/PCy were tested on primary cultured rabbit chondrocytes stimulated by interleukin-1 beta (IL-1β). The results showed that HT/PCy exerts anti-inflammatory and chondroprotective actions in vitro. The preventive effect of HT/PCy association was assessed in two animal models of post-traumatic OA in mice and rabbits. Diet supplementation with HT/PCy significantly decreased the severity of post-traumatic osteoarthritis in two complementary mice and rabbit models. The bioavailability and bioactivity was evaluated following gavage with HT/PCy in rabbits. Regular metabolites from HT/PCy extract were found in sera from rabbits following oral intake. Finally, sera from rabbits force-fed with HT/PCy conserved anti-IL-1β effect, suggesting the bioactivity of this extract. To conclude, HT/PCy extract may be of clinical significance for the preventive treatment of osteoarthritis.

Enriching oils, such as olive oil, could be one solution to tackle the worldwide epidemic of vitamin D deficiency and to better fit with omega 3 (DHA) recommendations. However, data regarding the interactions occurring at the intestinal level between vitamin D and phenols from olive oil are scarce. We first determined the effect of polyphenols from a virgin olive oil, and a virgin olive oil enriched with DHA, on vitamin D absorption in rats. We then investigated the effects of 3 main olive oil phenols (oleuropein, hydroxytyrosol and pinoresinol) on vitamin D uptake by Caco-2 cells. The presence of polyphenols in the olive oil supplemented with DHA inhibited vitamin D postprandial response in rats (-25%, p<0.05). Similar results were obtained with a mix of the 3 polyphenols delivered to Caco-2 cells. However, this inhibitory effect was due to the presence of pinoresinol only. As the pinoresinol content can highly vary between olive oils, the present results should be taken into account to formulate an appropriate oil product enriched in vitamin D., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Dietary supplementation with dried plum (DP) has been shown to protect against and reverse established osteopenia in ovariectomized rodents. Based on in vitro studies, we hypothesized that DP polyphenols may be responsible for that bone-sparing effect. This study was designed to (1) analyze whether the main phenolic acids of DP control preosteoblast proliferation and activity in vitro; (2) determine if the polyphenolic content of DP or DP juice concentrate is the main component improving bone health in vivo; and (3) analyze whether DP metabolites directly modulate preosteoblast physiology ex vivo. In vitro, we found that neochlorogenic, chlorogenic, and caffeic acids induce the proliferation and repress the alkaline phosphatase activity of primary preosteoblasts in a dose-dependent manner. In vivo, low-chlorogenic acid Agen prunes (AP) enriched with a high-fiber diet and low-chlorogenic acid AP juice concentrate prevented the decrease of total femoral bone mineral density induced by estrogen deficiency in 5-month-old female rats and positively restored the variations of the bone markers osteocalcin and deoxypyridinoline. Ex vivo, we demonstrated that serum from rats fed with low-chlorogenic acid AP enriched with a high-fiber diet showed repressed proliferation and stimulated alkaline phosphatase activity of primary preosteoblasts. Overall, the beneficial action of AP on bone health was not dependent on its polyphenolic content., (Copyright © 2016 Elsevier Inc. All rights reserved.)

GPR40 is a free fatty acid receptor that has been recently shown to impact bone remodeling. This receptor protects skeleton by inhibiting bone resorbing osteoclast differentiation. Consistent with GPR40 expression on bone forming cells, we assumed that this receptor may also influence osteoblast activity. To further investigate this hypothesis, biological effects of GW9508, a synthetic agonist for GPR40, was first tested on osteoblast differentiation parameters. Assays were performed in two different cell models: the MC3T3-E1 osteoblastic cell line and primary bone marrow cultures extracted from wild-type and GPR40 knock-out mice. Both models showed a dual role of GPR40 on osteoblasts. Although receptor stimulation induced early stimulation of differentiation marker expression, it finally led to inhibition of mineralization process during late differentiation stages. To further elucidate this discrepancy, mice were ovariectomized to induce bone loss and received GPR40 agonist by gavage. Data revealed a weak influence of GPR40 agonist on osteoblast markers expression. Nevertheless, a significant increase in OPG expression was observed upon GW9508 treatment that contribute to explain the GPR40-related osteoporosis prevention. To conclude, our results confirm the relevance of this new opportunity in the management of bone loss.

The nutritional benefits of pomegranate have attracted great scientific interest. The pomegranate, including the pomegranate peel, has been used worldwide for many years as a fruit with medicinal activity, mostly antioxidant properties. Among chronic diseases, osteoporosis, which is associated with bone remodelling impairment leading to progressive bone loss, could eventually benefit from antioxidant compounds because of the involvement of oxidative stress in the pathogenesis of osteopenia. In this study, with in vivo and ex vivo experiments, we investigated whether the consumption of pomegranate peel extract (PGPE) could limit the process of osteopenia. We demonstrated that in ovariectomized (OVX) C57BL/6J mice, PGPE consumption was able to significantly prevent the decrease in bone mineral density (-31.9%; p < 0.001 vs. OVX mice) and bone microarchitecture impairment. Moreover, the exposure of RAW264.7 cells to serum harvested from mice that had been given a PGPE-enriched diet elicited reduced osteoclast differentiation and bone resorption, as shown by the inhibition of the major osteoclast markers. In addition, PGPE appeared to substantially stimulate osteoblastic MC3T3-E1 alkaline phosphatase (ALP) activity at day 7, mineralization at day 21 and the transcription level of osteogenic markers. PGPE may be effective in preventing the bone loss associated with ovariectomy in mice, and offers a promising alternative for the nutritional management of this disease.

Purpose: The aim of this study was to evaluate and compare the musculoskeletal effects induced by ovariectomy-related fat mass deposition against the musculoskeletal effects caused by a high-fat diet., Methods: A group of adult female rats was ovariectomized and fed a control diet. Two additional groups were sham-operated and fed a control or a high-fat diet for 19 weeks. Distal femur and serum bone parameters were measured to assess bone metabolism. Muscle protein metabolism, mitochondrial markers and triglyceride content were evaluated in tibialis anterior. Triglyceride content was evaluated in liver. Circulating inflammatory and metabolic markers were determined., Results: The high-fat diet and ovariectomy led to similar increases in fat mass (+36.6-56.7%; p < 0.05) but had different impacts on bone and muscle tissues and inflammatory markers. Consumption of the high-fat diet led to decreased bone formation (-38.4%; p < 0.05), impaired muscle mitochondrial metabolism, muscle lipotoxicity and a 20.9% increase in tibialis anterior protein synthesis rate (p < 0.05). Ovariectomy was associated with higher bone turnover as bone formation increased +72.7% (p < 0.05) and bone resorption increased +76.4% (p < 0.05), leading to bone loss, a 17.9% decrease in muscle protein synthesis rate (p < 0.05) and liver lipotoxicity., Conclusions: In female rats, high-fat diet and ovariectomy triggered similar gains in fat mass but had different impacts on bone and muscle metabolism. The ovariectomy-induced mechanisms affecting the musculoskeletal system are mainly caused by estrogen depletion, which surpasses the potential-independent effect of adiposity.

Osteoarthritis (OA) is an age-related degenerative joint disease. To date, its management is focused on symptoms (pain and inflammation). Studies suggest that fatty acids can reduce the expression of inflammatory and catalytic mediators, and improve in vivo joint function. Free fatty acid receptors (FFARs) such as G-protein coupled receptor 40 (GPR40) are proposed as attractive therapeutic targets to counteract inflammation and cartilage degradation observed in OA. This study aims to elucidate the involvement of GPR40 in OA. In this study, we used an in vitro model of OA, and surgically induced OA by ligament transection and partial meniscectomy in wild-type and GPR40 deficient mice. OA phenotype was investigated in vivo by histology and genes expression. We demonstrate that IL-1β-treated GPR40(-/-) chondrocytes secret more inflammatory mediators (nitric oxide, interleukin-6, prostaglandin E2) and active catabolic enzymes (metalloproteinase-2, -9 [MMP-2, MMP-9]), and show decreased anabolism (glycoaminoglycan) compared to GPR40(+/+) cells. In accordance with these results, we show that GPR40(-/-) mice exhibit an aggravated OA-induced phenotype characterized by higher tidemark exposure, frequency of osteophyte formation and subchondral bone sclerosis. Altogether our results demonstrate that GPR40 deficiency leads to an extended OA phenotype, providing evidence that increasing GPR40 activity, by natural or synthetic ligands, could be a new strategy in the management of OA., (© 2015 by the Society for Experimental Biology and Medicine.)

As bones are levers for skeletal muscle to exert forces, both are complementary and essential for locomotion and individual autonomy. In the past decades, the idea of a bone-muscle unit has emerged. Numerous studies have confirmed this hypothesis from in utero to aging works. Space flight, bed rest as well as osteoporosis and sarcopenia experimentations have allowed to accumulate considerable evidence. Mechanical loading is a key mechanism linking both tissues with a central promoting role of physical activity. Moreover, the skeletal muscle secretome accounts various molecules that affect bone including insulin-like growth factor-1 (IGF-1), basic fibroblast growth factor (FGF-2), interleukin-6 (IL-6), IL-15, myostatin, osteoglycin (OGN), FAM5C, Tmem119 and osteoactivin. Even though studies on the potential effects of bone on muscle metabolism are sparse, few osteokines have been identified. Prostaglandin E2 (PGE2) and Wnt3a, which are secreted by osteocytes, osteocalcin (OCN) and IGF-1, which are produced by osteoblasts and sclerostin which is secreted by both cell types, might impact skeletal muscle cells. Cartilage and adipose tissue are also likely to participate to this control loop and should not be set aside. Indeed, chondrocytes are known to secrete Dickkopf-1 (DKK-1) and Indian hedgehog (Ihh) and adipocytes produce leptin, adiponectin and IL-6, which potentially modulate bone and muscle metabolisms. The understanding of this system will enable to define new levers to prevent/treat sarcopenia and osteoporosis at the same time. These strategies might include nutritional interventions and physical exercise., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Despite the growing interest in deciphering the causes and consequences of obesity-related disorders, the mechanisms linking fat intake to bone behaviour remain unclear. Since bone fractures are widely associated with increased morbidity and mortality, most notably in elderly and obese people, bone health has become a major social and economic issue. Consistently, public health system guidelines have encouraged low-fat diets in order to reduce associated complications. However, from a bone point of view, mechanisms linking fat intake to bone alteration remain quite controversial. Thus, after more than a decade of dedicated studies, this timely review offers a comprehensive overview of the relationships between bone and fatty acids. Using clinical evidences as a starting-point to more complex molecular elucidation, this work highlights the complexity of the system and reveals that bone alteration that cannot be solved simply by taking ω-3 pills. Fatty acid effects on bone metabolism can be both direct and indirect and require integrated investigations. Furthermore, even at the level of a single cell, one fatty acid is able to trigger several different independent pathways (receptors, metabolites…) which may all have a say in the final cellular metabolic response., (Copyright © 2015 Elsevier Ltd. All rights reserved.)