Dietary lipids modulate bone prostaglandin E2 production, insulin-like growth factor-I concentration and formation rate in chicks

Genetic background of walking ability and its relationship with leg defects, mortality, and performance traits in turkeys (Meleagris gallopavo)

This study aimed to explore the genetic basis of walking ability and potentially related performance traits in turkey purebred populations. Phenotypic, pedigree, and genomic datasets from 2 turkey lines hatched between 2010 and 2023 were included in the study. Walking ability data, defined based on a scoring system ranging from 1 (worst) to 6 (best), were collected on 192,019 animals of a female line and 235,461 animals of a male line. Genomic information was obtained for 46,427 turkeys (22,302 from a female line and 24,125 from a male line) using a 65K single nucleotide polymorphism (SNP) panel. Variance components and heritability for walking ability were estimated. Furthermore, genetic and phenotypic correlations among walking ability, mortality and disorders, and performance traits were calculated. A genome-wide association study (GWAS) was also conducted to identify SNPs associated with walking ability. Walking ability is moderately heritable (0.23 ± 0.01) in both turkey lines. The genetic correlations between walking ability and the other evaluated traits ranged from -0.02 to -0.78, with leg defects exhibiting the strongest negative correlation with walking ability. In the female line, 31 SNPs were associated with walking ability and overlapped with 116 genes. These positional genes are linked to 6 gene ontology (GO) terms. Notably, genes such as CSRP2, DDX1, RHBDL1, SEZ6L, and CTSK are involved in growth, development, locomotion, and bone disorders. GO terms, including fibronectin binding (GO:0001968), peptide cross-linking (GO:0018149), and catabolic process (GO:0009057), are directly linked with mobility. In the male line, 66 markers associated with walking ability were identified and overlapped with 281 genes. These genes are linked to 12 GO terms. Genes such as RB1CC1, TNNI1, MSTN, FN1, SIK3, PADI2, ERBB4, B3GNT2, and BACE1 are associated with cell growth, myostatin development, and disorders. GO terms in the male line are predominantly related to lipid metabolism. In conclusion, walking ability is moderately heritable in both populations. Furthermore, walking ability can be enhanced through targeted genetic selection, emphasizing its relevance to both animal welfare and productivity.

Conjugated linoleic acid and glucosamine supplements may prevent bone loss in aging by regulating the RANKL/RANK/OPG pathway

The skeleton is a living organ that undergoes constant changes, including bone formation and resorption. It is affected by various diseases, such as osteoporosis, osteopenia, and osteomalacia. Nowadays, several methods are applied to protect bone health, including the use of hormonal and non-hormonal medications and supplements. However, certain drugs like glucocorticoids, thiazolidinediones, heparin, anticonvulsants, chemotherapy, and proton pump inhibitors can endanger bone health and cause bone loss. New studies are exploring the use of supplements, such as conjugated linoleic acid (CLA) and glucosamine, with fewer side effects during treatment. Various mechanisms have been proposed for the effects of CLA and glucosamine on bone structure, both direct and indirect. One mechanism that deserves special attention is the regulatory effect of RANKL/RANK/OPG on bone turnover. The RANKL/RANK/OPG pathway is considered a motive for osteoclast maturation and bone resorption. The cytokine system, consisting of the receptor activator of the nuclear factor (NF)-kB ligand (RANKL), its receptor RANK, and its decoy receptor, osteoprotegerin (OPG), plays a vital role in bone turnover. Over the past few years, researchers have observed the impact of CLA and glucosamine on the RANKL/RANK/OPG mechanism of bone turnover. However, no comprehensive study has been published on these supplements and their mechanism. To address this gap in knowledge, we have critically reviewed their potential effects. This review aims to assist in developing efficient treatment strategies and focusing future studies on these supplements.

The effects of maternal fish oil supplementation rich in n-3 PUFA on offspring-broiler growth performance, body composition and bone microstructure

This study evaluated the effects of maternal fish oil supplementation rich in n-3 PUFA on the performance and bone health of offspring broilers at embryonic development stage and at market age. Ross 708 broiler breeder hens were fed standard diets containing either 2.3% soybean oil (SO) or fish oil (FO) for 28 days. Their fertilized eggs were collected and hatched. For a pre-hatch study, left tibia samples were collected at 18 days of incubation. For a post-hatch study, a total of 240 male chicks from each maternal treatment were randomly selected and assigned to 12 floor pens and provided with the same broiler diets. At 42 days of age, growth performance, body composition, bone microstructure, and expression of key bone marrow osteogenic and adipogenic genes were evaluated. One-way ANOVA was performed, and means were compared by student’s t-test. Maternal use of FO in breeder hen diet increased bone mineral content (p < 0.01), bone tissue volume (p < 0.05), and bone surface area (p < 0.05), but decreased total porosity volume (p < 0.01) during the embryonic development period. The FO group showed higher body weight gain and feed intake at the finisher stage than the SO group. Body composition analyses by dual-energy X-ray absorptiometry showed that the FO group had higher fat percentage and higher fat mass at day 1, but higher lean mass and total body mass at market age. The decreased expression of key adipogenic genes in the FO group suggested that prenatal FO supplementation in breeder hen diet suppressed adipogenesis in offspring bone marrow. Furthermore, no major differences were observed in expression of osteogenesis marker genes, microstructure change in trabecular bone, or bone mineral density. However, a significant higher close pores/open pores ratio suggested an improvement on bone health of the FO group. Thus, this study indicates that maternal fish oil diet rich in n-3 PUFA could have a favorable impact on fat mass and skeletal integrity in broiler offspring.

The Diverse Roles of 17β-Estradiol in Non-Gonadal Tissues and Its Consequential Impact on Reproduction in Laying and Broiler Breeder Hens

Estradiol-17β (E2) has long been studied as the primary estrogen involved in sexual maturation of hens. Due to the oviparous nature of avian species, ovarian production of E2 has been indicated as the key steroid responsible for activating the formation of the eggshell and internal egg components in hens. This involves the integration and coordination between ovarian follicular development, liver metabolism and bone physiology to produce the follicle, yolk and albumen, and shell, respectively. However, the ability of E2 to be synthesized by non-gonadal tissues such as the skin, heart, muscle, liver, brain, adipose tissue, pancreas, and adrenal glands demonstrates the capability of this hormone to influence a variety of physiological processes. Thus, in this review, we intend to re-establish the role of E2 within these tissues and identify direct and indirect integration between the control of reproduction, metabolism, and bone physiology. Specifically, the sources of E2 and its activity in these tissues via the estrogen receptors (ERα, ERβ, GPR30) is described. This is followed by an update on the role of E2 during sexual differentiation of the embryo and maturation of the hen. We then also consider the implications of the recent discovery of additional E2 elevations during an extended laying cycle. Next, the specific roles of E2 in yolk formation and skeletal development are outlined. Finally, the consequences of altered E2 production in mature hens and the associated disorders are discussed. While these areas of study have been previously independently considered, this comprehensive review intends to highlight the critical roles played by E2 to alter and coordinate physiological processes in preparation for the laying cycle.

The Effects of Different Dietary Oil Sources on Broiler Chicken Bone Mineralization

This study was designed to determine the effects of dietary hazelnut oil (HO) and sunflower oil (SO) on the mineral composition of chicken femur and tibia bones. A 40-day trial was initiated with 600 1-day-old Ross 308 chickens. Initially, the chickens were randomly divided into four main groups of 150 each according to the proportion of SO and HO supplementation in their diets: control SO (25 g/kg SO), LHO (25 g/kg HO), HHO (50 g/kg HO), and MO (50 g/kg blend of 25 g/kg SO + 25 g/kg HO). Each group was further divided into six subgroups of 25 chickens. At the end of the trial, four chickens from each of the six subgroups were randomly selected and slaughtered. Their right tibia and right femur bones were isolated and analyzed for macro (Ca, P, Mg) and trace (Fe, Cu, Mn, Zn, Cr, Co, and Se) minerals in addition to ether extract and ash. The results suggest that the diets' fat concentration and fatty acid composition significantly affected the Ca, P, Mg, Fe, Cu, Cr, and Se composition of tibia bones (p < 0.01). The ether extract and ash contents of the femur bones were increased in both HHO and MO groups (p < 0.05), while Fe and Cr compositions were lower in all femur bones, except those from SO chickens (p < 0.05). The Se content of femur bones in the LHO group was higher than the other treatment groups (p < 0.05). In conclusion, the amount of oil and fatty acid in the diet affected the accumulation of Ca, P, Mg, Fe, Cu, and Cr minerals in the tibia bone. Moreover, the amount of Cr and Fe was lower in the femur and tibia bones in the group that received the HO supplement and all groups in which the amount of oil fed was increased.

Influence of Feeding Omega-3 Polyunsaturated Fatty Acids to Broiler Breeders on Indices of Immunocompetence, Gastrointestinal, and Skeletal Development in Broiler Chickens

Modern broiler chickens are associated with rapid growth rates and superior feed efficiency. However, they are also susceptible to physiological and metabolic disorders (e.g., skin lesions, lameness, sudden death, enteric diseases, myopathies) that exert substantial economic losses to producers. This is further exacerbated by consumer pressure and mandated cessation of production practices such as indiscriminate use of antimicrobial growth promoters. Manipulation of broiler breeder (BB) nutrition and management can influence chick quality, robustness, and resilience to stressors in the production environment. The present review examines the role of feeding BB functional polyunsaturated omega-3 fatty acids (n-3 PUFA) and subsequent impact on the indices of immunocompetence, skeletal, and gastrointestinal (GIT) development in broiler chickens. Research in mammalian and avian models led evidence that perinatal feeding of long chain n-3 PUFA such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) engender transgenerational effects through regulation of a variety of biological processes including development of vital organs such as skeleton, brain and GIT. It is shown that feeding poultry breeders n-3 PUFA decreases inflammatory states and enriches hatching eggs with n-3 PUFA and immunoglobulins. Further evidence also shows that after 15 days of incubation, chicken embryos preferentially utilize long chain n-3 PUFA-critical for optimal cell, tissues, and organ development. Enrichment of n-3 PUFA in newly hatchling tissues reduce proinflammatory eicosanoids with consequences of enhanced bone mineralization. Dietary n-3 PUFA also modulates breeder GIT microbiota with consequences of microbial colonization and succession in chicks. As well, research shows that feeding poultry breeders n-3 PUFA bolsters progeny immunocompetence through enhanced passive immunity and antibody titres against routine vaccination. In conclusion, it appears that chicks may benefit from the incorporation of n-3 PUFA in the breeder diets; however, little attention is paid to fatty acids composition in breeder nutrition. We also highlight gaps in knowledge and future research perspectives.

Camelina Oil Supplementation Improves Bone Parameters in Ovariectomized Rats

The aim of the present study was to determine the effect of administration of Camelina sativa oil (CO) as a source of polyunsaturated fatty acids (PUFA) on bone parameters in ovariectomized rats (OVX). Overall, 40 10-week-old healthy female Wistar rats were divided into 4 groups with 10 animals in each. Rats in the control group (SHO) were subjected to a sham operation, whereas experimental rats (OVX) were ovariectomized. After a 7-day recovery period, the SHO the rats received orally 1 mL of physiological saline for the next 6 weeks. The OVX rats received orally 1 mL of physiological saline (OVX-PhS), 5 g/kg BW (OVX-CO5), or 9 g/kg BW (OVX-CO9) of camelina oil. The use of camelina oil had a significant effect on body weight, lean mass, and fat mass. The camelina oil administration suppressed the decrease in the values of some densitometric, tomographic, and mechanical parameters of femur caused by estrogen deficiency. The CO treatment increased significantly the serum level of osteocalcin and decreased the serum level of C-terminal telopeptide of type I collagen in the OVX rats. In conclusion, camelina oil exerts a positive osteotropic effect by inhibiting ovariectomy-induced adverse changes in bones. Camelina oil supplementation can be used as an efficient method for improving bone health in a disturbed state. However, further research must be carried out on other animal species supplemented with the oil.

Effects of Fish Oil and Dietary Antioxidant Supplementation on Bone Health of Growing Lambs

Simple Summary

The current study investigated the bone status of growing lambs fed diets supplemented with bioactive components (fish oil, carnosic acid, SeY, and Na₂SeO₃) improving bone parameters. The study provides new information with regards to the positive role of bioactive components supplemented to diets for growing lambs on their femur characteristics (bone content, bone mineral density, geometry, and strength).

Abstract

The aim of the present study was to assess the effects of partial replacement of rapeseed oil (RO) with fish oil (FO) combined with dietary supplementation of various antioxidants on the characteristics of lamb femur. Thirty male lambs were assigned to five dietary treatments and fed isoproteinous and isoenergetic diets for 35 days. The control diet was enriched with 3.0% RO, while the experimental diets were enriched either only with 2.0% RO and 1.0% FO or additionally with 0.1% carnosic acid, 0.1% carnosic acid and 0.35 ppm Se as selenized yeast, or 0.1% carnosic acid and 0.35 ppm Se as sodium selenite. After 35 days, the lambs were slaughtered, and the femur was dissected from the carcass of each animal and analyzed for morphometric, geometric, densitometric, and biomechanical properties. The dietary modifications, specifically the supplementation of FO and selenized yeast, significantly improved the geometric, densitometric, and biomechanical properties of lamb femur.

Arachidonic acid status negatively associates with forearm bone outcomes and glucose homeostasis in children with an overweight condition or obesity

Long-chain polyunsaturated fatty acids are implicated in musculoskeletal health in adults. This study examined whether fatty acid status relates to bone health outcomes in children with overweight condition or obesity (body mass index z score, 3.1 ± 0.1; age, 9.0 ± 0.2 years; n = 108). Nondominant forearm bone density (distal one-third), geometry (4% site), and soft tissue composition (66%) were assessed using dual-energy X-ray absorptiometry and peripheral quantitative computed tomography. Red blood cell (RBC) fatty acid profile and indices of glucose homeostasis were measured. Differences in outcomes among RBC arachidonic acid (AA, C20:4n-6) tertiles were tested using mixed-model ANOVA. Ultra-, mid-, and total-distal forearm bone mineral content, adjusted for sex, age, percentage body fat, race, and forearm length, were 10% to 13% greater in children in the first AA tertile relative to the third. Children in the second tertile had the highest bone cross-sectional area and estimated strength at the 66% radius. Muscle cross-sectional area was 15% lower in the third tertile compared with the first, along with higher fasting insulin concentrations (27%) and homeostasis model of assessment estimate of insulin resistance (31%). Higher RBC AA status aligns with deficits in forearm bone mass, geometry, and muscle mass in children with excess adiposity and early signs of insulin resistance. Novelty Higher arachidonic acid status is associated with lower forearm bone mass in children with overweight condition or obesity. Children with higher arachidonic acid status had increased fasting insulin concentrations and indices of insulin resistance.

Long term effect of dietary lipid saturation on eggshell quality and bone characteristics of laying hens

This study investigated the long-term effect of dietary fatty acid saturation on eggshell quality and bone characteristics of laying hens at end of lay. Five isoenergetic (3,011.5 kcal AME/kg DM) and isonitrogenous (169 g CP/kg DM) diets were formulated using different lipid sources at a constant 30 g/kg inclusion level. The control, polyunsaturated omega-3 (PUFA n-3), polyunsaturated omega-6 (PUFA n-6), monounsaturated omega-9 (MUFA n-9), and saturated fatty acid (SFA) diets consisted of linseed- and fish oil (50:50 blend), fish oil, sunflower oil, high oleic acid sunflower oil, and tallow, respectively. A total of 200 individually caged Hy-Line Silver-Brown hens (20 wk of age) were randomly allocated to the 5 treatments (n = 40 replicates/treatment) and received the experimental diets for 54 wk. During weeks 58, 62, 66, 70, and 74 of age (end-of-lay period), 20 eggs/treatment per day (n = 140 eggs/treatment per week) were selected for determining eggshell quality traits. At 74 wk of age, 10 birds per treatment (n = 10 birds/treatment) were randomly selected for the determination of bone quality characteristics. Data were statistically analyzed (P < 0.05) using a fully randomized 1-way ANOVA. Dietary treatment had no effect (P > 0.05) on eggshell quality traits. The MUFA n-9 treatment with the highest unsaturated to SFA ratio (UFA: SFA) resulted in a higher (P < 0.05) femur weight (10.34 g) as well as femur- (52.99%) and tibia ash (51.07%) content than the SFA treatment. Also, the PUFA n-3 diet resulted in a higher (P < 0.05) femur weight (10.21 g), femur ash (51.82%), and percentage femur (0.57%) compared to the SFA diet. Results suggested that prolonged feeding of diets varying in FA profile had no negative effect on eggshell quality, whereas UFA: SFA and long-chain n-3 PUFA affected the bone quality (especially the femur) of hens at the end of lay.

Bone Mineral Density as a Predictor of Atherogenic Indexes of Cardiovascular Disease, Especially in Nonobese Adults

Purpose

This study is aimed at determining whether bone mineral density (BMD) values are related to atherogenic indexes (AIs) and could predict the risk of cardiovascular disease (CVD) in southern Taiwanese adults.

Methods

Medical records of 3249 adults who underwent health examinations between June 2014 and February 2018 at a regional hospital in southern Taiwan were reviewed. Data collected included health history, anthropomorphic characteristics, exercise habits, diets (vegetarian or nonvegetarian), clinical laboratory results (lipid profile, systemic blood pressure (SBP), glucose level, creatinine (Cre) level, and hemoglobin (Hb) level), and bone mineral density (BMD), which were used to identify the associations of these parameters, especially BMD, with lipid profile and calculated AIs through simple and multiple linear regressions.

Results

The mean age of the patients was 58.0 years, and 71.4% were male. Body mass index (BMI), SBP, glucose level, Cre level, Hb level, and all BMD values were positively correlated with triglyceride (TG) level and AIs and were negatively correlated with high-density lipoprotein cholesterol (HDL-C) level. The significant positive correlations of BMD at all the measured sites with AIs remained after adjusting for age, sex, SBP, glucose level, Cre level, Hb level, smoking, exercise habits, and vegetarian state. The expanded adjusting model for TG/HDL-C remained significant at all the BMD measured sites in nonobese men, at bilateral femoral neck and total hips in nonobese women, and at the bilateral total hips in obese women.

Conclusions

AIs are predictive markers for CVD, and BMD values are predictors of AIs, especially the novel AI, i.e., TG/HDL-C ratio, in nonobese adult men and women after dividing the patients into subgroups to eliminate the effect of BMI as a confounding factor. Thus, BMD values could predict AIs of CVD, especially in nonobese adults.

Dairy foods and positive impact on the consumer's health

The objective of the present chapter was to demonstrate the state of the art in the recent advances in nutritional and functional components of dairy products research. In this chapter, the main mechanisms responsible and essential for a better understanding of nutritional and functional values of the components of milk and dairy products are highlighted. It also includes a discussion about the positive impacts of fermented milk, cheese, butter, ice cream, and dairy desserts components on the consumer's health.

Dietary supplementation of conjugated linoleic acid in horses: establishment of baseline values on bone turnover, synovial prostaglandin E2, and gait kinematics

Conjugated linoleic acid (CLA) has shown anti-inflammatory effects in laboratory and food animal species by modulating production of proinflammatory cytokines and inhibiting cyclooxygenase 2 (COX2), reducing prostaglandin E2 (PGE2) production. Bone remodelling may also be affected by CLA. Thus, CLA may reduce inflammation consistent with joint disease. Effects of CLA supplementation in horses have not been previously reported. This study aimed to determine baseline values of CLA supplementation on bone turnover, synovial PGE2 and gait kinematics in mature, idle horses. It was not expected that CLA would affect bone metabolism or gait kinematics in this animal model, as COX2 pathway should not be upregulated. In a crossover study, 12 mature mares were blocked by breed, age, and body condition score and separated into two treatment groups (n=6 per group) fed CLA or corn oil (CO; isocaloric control) for two 6-week feeding periods, separated by a 4-week period when oil treatment was withheld. Corn oil or CLA supplement (55% mixed CLA isomers) was incorporated into diets at 0.01% body weight/day. Blood and synovial fluid samples were collected before (day 0) and after (day 42) each feeding period for evaluation of serum bone alkaline phosphatase (BAP) and deoxypyridinoline (DPD) and synovial PGE2. Stride length and fetlock flexion and extension were captured on day 0 and 42 of period 1. ANOVA was conducted to compare the response of BAP, DPD, and PGE2 of CLA-treated and control mares. Kinematic data were analysed with Student t-tests. Dietary CLA supplementation did not affect serum BAP or DPD, synovial PGE2, or stride length (all P>0.05). This study provides a baseline for CLA supplementation on bone metabolism and gait kinematics in horses; CLA supplementation in horses at varying levels of growth, exercise, and progression of joint disease may now be more revealing.

Dietary Conjugated Linoleic Acid Does Not Adversely Affect Bone Mass in Obese fa/fa or Lean Zucker Rats

Conjugated linoleic acid (CLA) elevates body ash in healthy animals. The objective of the present study was to determine if single or mixed CLA isomers improve bone mass in an obese and hyperinsulinemic state. Male (n = 120) lean and obese fa/fa Zucker rats (age, 6 weeks) were randomized to 8 weeks on a control diet or to 0.4% (w/w) cis-9, trans-11 CLA (Group 1); 0.4% (w/w) trans-10, cis-12 CLA (Group 2); 0.4% (w/w) cis-9, trans-11 CLA and 0.4% (w/w) trans-10, cis-12 CLA (Group 3); 0.4% (w/w) cis-9, trans-11 CLA, 0.4% (w/w) trans-10, cis-12 CLA, and traces of other CLA isomers (Group 4); and 0.4% (w/w) cis-9, trans-11 CLA, 0.4% (w/w) trans-10, cis-12 CLA, and 0.3% (w/w) other CLA isomers (Group 5). Bone area (BA), bone mineral content (BMC), and bone mineral density (BMD) of the whole body, spine, and femur were measured at baseline (6 weeks) and at 14 weeks of age. Effects of genotype, diet, and genotype × diet interactions were assessed using factorial analysis of variance. At 6 and 14 weeks, whole-body BA and BMC were lower in lean rats compared with fa/fa rats. Similarly, at 14 weeks, fa/fa rats had a higher spine and femur BMD despite a lower femur weight. The fa/fa rats in Groups 4 and 5 had higher adjusted whole-body BMC compared with Group 3, but not with Group 1, Group 2, or the control. In lean rats, Group 3 had a greater adjusted whole-body BMC than Groups 1 and 2, but not Group 4, Group 5, or the control. Thus, commercially available CLA mixtures and single CLA isomers do not affect bone mass in a hyperinsulinemic, obese state.

CLA Has a Useful Effect on Bone Markers in Patients with Rheumatoid Arthritis

Rheumatoid arthritis is a systemic, chronic disease which may increase the risk of osteoporosis. This study was carried out in order to examine the effect of conjugated linoleic acid (CLA) on bone markers in rheumatoid arthritis disease which is the most common autoimmune disease. The present study is a randomized double-blind clinical trial. Subjects included 52 patients with active rheumatoid arthritis who were divided into two groups. Group I received standard treatment plus 2 daily 1.25 g capsules (Containing about 2 g of 9-cis 11-trans isomer and 10-cis 12-trans isomer in ratio of 50 -50 CLA in glycerinated form), Group II received standard treatment plus 2 Placebo 1.25 g capsules containing sunflower oil with high oleic acid. Telopeptides C, osteocalcin, and MMP3 were analyzed by ELISA method, PGE₂ was done by competitive enzymatic immunoassay method, and IGF-1 was analyzed by the IRMA method based on the sandwich method and ALK-P of bone. Before and after the intervention, the questionnaires about general information, nutrition assessment and medical history were filled out by the subjects. Nutritional assessment was done by a 24-h record questionnaire for the three-day diet. The results were analyzed using SPSS software (version 18).

FINDINGS

There was no significant difference between the groups in enzyme activity of ALK-P of bone, PGE₂ and MMP3 variables. However, differences between the two groups in terms of activity of telopeptides C, Osteocalcin, and IGF1 were significant (P < 0.05). CLA has a potentially beneficial effect on bone markers in patients with rheumatoid arthritis. Therefore, in order to study the effect of CLA on bone health in patients with RA and all patients with autoimmune and bone diseases more studies with longer duration and evaluation of bone mass density are required.

Lipid-lowering effects of Zanthoxylum schinifolium Siebold & Zucc. seed oil (ZSO) in hyperlipidemic rats and lipolytic effects in 3T3-L1 adipocytes

On the basis of the antiatherosclerotic effect of Zanthoxylum schinifolium, the therapeutic potential of Zanthoxylum schinifolium seed oil (ZSO) was tested in terms of the blood lipid profile and obesity in rats. The lipolytic effects of ZSO were determined in adipocytes and the total body and liver weight were decreased in rats. Compared with the high-cholesterol high-fat (HCHF) group, the rats in the HCHF+ZSO group showed improved levels of hyperlipidemia indicators. Furthermore, western blot analysis confirmed that the improvement of hyperlipidemia indicators was induced by stimulation of lipoprotein lipase expression. Additional results indicated that the reduction in body weight was likely caused by phosphorylation of hormone-sensitive lipase (HSL) via the protein kinase A pathway, ultimately leading to lipolysis. In conclusion, the results of the in vivo experiment showed that ZSO improved the lipid profiles in the blood, lowering cardiovascular disease and arteriosclerosis and degrading cellular lipids by activating HSL.

Molecular cloning and expression analysis of the retinoid X receptor (RXR) gene in golden pompano Trachinotus ovatus fed Artemia nauplii with different enrichments

The retinoid X receptors (RXRs) are involved in the skeletal development and other biological process such as blood vessel formation and metabolism. Partial sequences of RXRα and β genes were obtained, and their expressions were quantified on golden pompano Trachinotus ovatus at 28 days post hatching (DPH) to explore the molecular response to nutritional manipulation in fish larvae. As live food, Artemia nauplii were separately enriched with Nannochloropsis and Algamac 3080 and non-enriched Artemia nauplii (control) for fish feeding. The expressions of RXRs were detected in the embryos and fish larvae at early stages, suggesting that the skeletal development in golden pompano initiated before yolk re-sorption completion. Fish fed non-enriched Artemia nauplii ended up with higher jaw malformation. The highest specific growth rate was obtained when fish were fed with the Artemia nauplii enriched with Algamac 3080, and the lowest growth rate was observed when fish were fed with unenriched Artemia nauplii. The highest survival was obtained when fish were fed with non-enriched or Nannochloropsis-enriched Artemia nauplii. This study indicates that the use of enriched formula for Artemia nauplii can significantly affect the expression levels of RXRs and jaw malformation of golden pompano larvae, but there is no clear correlation between RXRs expressions and malformation rates when fish are subjected to nutrient challenge.

trans-10,cis-12 CLA promotes osteoblastogenesis via SMAD mediated mechanism in bone marrow mesenchymal stem cells

The inverse relationship between osteoblast and adipocyte differentiation in bone marrow mesenchymal stem cells has been linked to overall bone mass. It has previously been reported that conjugated linoleic acid (CLA) inhibits adipogenesis via a peroxisome-proliferator activated receptor-γ (PPARγ) mediated mechanism, while it increases osteoblastogenesis via a PPARγ-independent mechanism in mesenchymal stem cells. This suggests potential implication of CLA on improving bone mass. Thus the purpose of this study was to determine involvement of CLA on regulation of osteoblastogenesis in murine mesenchymal stem cells by focusing on the Mothers against decapentaplegic (MAD)-related family of molecules 8 (SMAD8), one of key regulators of osteoblastogenesis. The trans-10,cis-12 CLA, but not the cis-9,trans-11, significantly increased osteoblastogenesis via SMAD8, and inhibited adipogenesis independent of SMAD8, while inhibiting factors regulating osteoclastogenesis in this model. These suggest that CLA may help improve osteoblastogenesis via a SMAD8 mediated mechanism.

Effects of linseed oil and palm oil on growth performance, tibia fatty acid and biomarkers of bone metabolism in broilers

1. This study was conducted to determine the effects of different dietary fat sources on growth performance, tibia fatty acids and biomarkers of bone metabolism in broilers. 2. One-d-old commercial Arbor Acres broilers were fed with a maize-soya bean basal diet for 42 d, supplemented with oils according to the following 5 treatments: lard (lard group); linseed oil (linseed oil group); palm oil (palm oil group); linseed oil + palm oil (60:40 or 40:60 w/w, LP-1 group and LP-2 group, respectively). 3. No significant differences in weight gain, feed intake and gain/feed ratio were observed between the lard and linseed oil groups. Birds fed on palm oil had significantly greater weight gain and feed intake than those fed on lard or linseed oil. Growth performance in LP-1 and LP-2 was significantly greater than that of single-oil groups. 4. Tibia growth and bone characteristics were not influenced by supplementation with lard, linseed oil, or palm oil alone, but broilers fed on a mixture of fats had significantly greater tibia weight and length compared to broilers fed on linseed oil. Bone mineral density in tibia was significantly increased in LP-1 and LP-2 groups. 5. Supplementation of linseed oil alone or in combination with palm oil enhanced apparent digestibility of calcium, reduced serum calcium and increased tibia calcium concentrations. Moreover, supplementation with linseed oil alone or in combination with palm oil had a positive effect on biomarkers of bone growth. 6. The combination of linseed and palm oils was beneficial for growth performance, tibia growth and biomarkers of bone metabolism.

Conjugated linoleic Acid prevents ovariectomy-induced bone loss in mice by modulating both osteoclastogenesis and osteoblastogenesis

Postmenopausal osteoporosis due to estrogen deficiency is associated with severe morbidity and mortality. Beneficial effects of conjugated linoleic acid (CLA) on bone mineral density (BMD) have been reported in mice, rats and humans, but the effect of long term CLA supplementation against ovariectomy-induced bone loss in mice and the mechanisms underlying this effect have not been studied yet. Eight-week old ovariectomized (Ovx) and sham operated C57BL/6 mice were fed either a diet containing 0.5 % safflower oil (SFO) or 0.5 % CLA for 24 weeks to examine BMD, bone turn over markers and osteotropic factors. Bone marrow (BM) cells were cultured to determine the effect on inflammation, osteoclastogenesis, and osteoblastogenesis. SFO/Ovx mice had significantly lower femoral, tibial and lumbar BMD compared to SFO/Sham mice; whereas, no difference was found between CLA/Ovx and CLA/Sham mice. CLA inhibited bone resorption markers whereas enhanced bone formation markers in Ovx mice as compared to SFO-fed mice. Reverse transcriptase polymerase chain reaction and fluorescence activated cell sorting analyses of splenocytes revealed that CLA inhibited pro-osteoclastogenic receptor activator of NF-κB (RANKL) and stimulated decoy receptor of RANKL, osteoprotegerin expression. CLA also inhibited pro-inflammatory cytokine and enhanced anti-inflammatory cytokine production of lipopolysaccharide-stimulated splenocytes and BM cells. Furthermore, CLA inhibited osteoclast differentiation in BM and stimulated osteoblast differentiation in BM stromal cells as confirmed by tartrate resistant acid phosphatase and Alizarin Red staining, respectively. In conclusion, CLA may prevent postmenopausal bone loss not only by inhibiting excessive bone resorption due to estrogen deficiency but also by stimulating new bone formation. CLA might be a potential alternative therapy against osteoporotic bone loss.

The effect of fatty acid positioning in dietary triacylglycerols and intake of long-chain n-3 polyunsaturated fatty acids on bone mineral accretion in growing piglets

Long-chain n-3 PUFA (LCPUFA) and palmitate (16:0) positioning in the triacylglycerol (TAG) of infant formula may affect calcium-uptake which could affect bone health. We investigated if a human milk fat substitute (HMFS) with a modified TAG structure holding 16:0 predominantly in the sn-2-position compared with a control (CONT) and if increasing n-3LCPUFA intake giving fish oil (FO) compared with sunflower oil (SO) would affect bone parameters in piglets in two sets of controlled 14d-interventions (n=12/group). We assessed this by dual-energy x-ray absorptiometry, and ex vivo peripheral quantitative computed tomography and mechanical strength. Bone mineral content (BMC) was higher in the FO compared to the SO-group (p=0.03). Despite similar weight gain in HMFS- and CONT-groups, body fat accumulation was higher with HMFS (p<0.001), and BMC, bone area (BA) and cortical BA in femur were lower (p=0.002, p=0.005, and p=0.02, respectively), indicating importance of both n-3LCPUFA and 16:0 TAG-positioning in infant formulas.

Changes of blood parameters associated with bone remodeling following experimentally induced fatty liver disorder in laying hens

Studies have demonstrated that obesity and osteoporosis are linked disorders in humans. This study examined the hypothesis that excessive lipid consumption affects bone metabolism in laying hens. A total of one hundred 63-wk-old laying hens were randomly divided into 2 treatments and fed either a regular layer diet (control) or a high energy and low protein diet (HE-LP; experimental treatment) for 80 d. Egg production, feed intake, and BW were recorded at various days during the treatment. At d 80, ten randomly chosen birds per treatment group were killed. Abdominal fat weight, liver weight, and liver fat content were determined. Serum levels of total calcium, inorganic phosphate, and alkaline phosphatase were measured using a biochemical analyzer. Serum concentrations of osteocalcin, leptin-like protein, and estrogen were measured by enzyme-linked immunosorbent assay. Tibia length and width were measured using a vernier caliper; density of the right tibias was determined using an x-ray scanner; and mechanical properties of the left tibias were analyzed using a material testing machine. The expression of osteocalcin and osteoprotegerin mRNA in the keel bone was analyzed by real-time PCR. The concentration of osteocalcin protein in the keels was measured using western blot. Compared with control hens, hens fed the HE-LP diet had lower egg production, lower feed intake, greater liver fat content, and greater abdominal fat pad mass (P < 0.05). Feeding the HE-LP diet increased serum alkaline phosphatase activity, osteocalcin, leptin-like protein, and estrogen concentrations (P < 0.05), and decreased the keel osteocalcin concentrations (P < 0.05). There were significant positive correlations between the serum concentrations of leptin-like protein, estrogen, and osteocalcin regardless of treatment (P < 0.05). The results indicated that HE-LP diet induced a fatty liver disorder in laying hens with an upregulation in bone turnover and exacerbated skeletal damage. The data supported a role for lipid metabolism in skeletal heath of laying hens.

Conjugated linoleic acid is related to bone mineral density but does not affect parathyroid hormone in men

The relationships between conjugated linoleic acid (CLA) status, bone, body composition, and the effect of CLA on calciotropic hormones are unclear. A cross-sectional study was designed to examine the association between c9, t11 CLA status in erythrocyte membranes (RBC) and body composition. This preceded a dose-response trial investigating if c9, t11 CLA affected parathyroid hormone (PTH). It was hypothesized that (1) higher c9, t11 CLA status in RBC will be associated with a lower fat and higher bone mass and that (2) PTH will be reduced by 30% after supplementation of c9, t11 CLA. Fifty-four men (age, 19-53 years) were included in the cross-sectional analysis, of which 31 were studied in the dose-response trial and randomized to 1 of 3 groups: placebo (n = 10), 1.5 g/d (n = 11), or 3.0 g/d (n = 10) of c9, t11 CLA for 16 weeks. Men with RBC c9, t11 CLA status above the median had higher whole body bone mineral density (BMD) (1.359 ± 0.024 vs 1.287 ± 0.023 g/cm(2); P = .04) and whole body lean mass (WBL) percentage (78.8% ± 0.9% vs 75.3% ± 1.0%; P = .01), whereas body mass index (24.8 ± 0.5 kg/m(2) vs 27.3 ± 0.9 kg/m(2); P = .01) and whole body fat mass percentage (17.3% ± 0.9% vs 21.3% ± 1.1%; P = .007) were lower. In regression analysis, RBC c9, t11 CLA status accounted for a significant proportion (r(2) = 0.10) of the variation in whole body BMD (P = .03). There were no time or treatment differences among any bone or biomarkers of bone metabolism including PTH. These findings indicate that RBC c9, t11 CLA status, a reflection of long-term (~4 months) dietary CLA intake, positively relates to BMD. However, c9, t11 CLA supplementation does not appear to affect PTH in healthy men.

Implication of conjugated linoleic acid (CLA) in human health

Conjugated linoleic acid (CLA) has drawn significant attention in the last two decades for its variety of biologically beneficial effects. CLA reduces body fat, cardiovascular diseases and cancer, and modulates immune and inflammatory responses as well as improves bone mass. It has been suggested that the overall effects of CLA are the results of interactions between two major isomers, cis-9,trans-11 and trans-10,cis-12. This review will primarily focus on current CLA publications involving humans, which are also summarized in the tables. Along with a number of beneficial effects of CLA, there are safety considerations for CLA supplementation in humans, which include effects on liver functions, milk fat depression, glucose metabolism, and oxidative stresses.

The effects of n-3 long-chain polyunsaturated fatty acids on bone formation and growth factors in adolescent boys

INTRODUCTION

Animal studies indicate that n-3 long-chain polyunsaturated fatty acids (LCPUFAs) increase bone formation. To our knowledge, no studies have examined this in growing humans. This study investigated whether bone mass and markers of bone formation and growth were (i) associated with docosahexaenoic acid (DHA) status and (ii) affected by fish oil supplementation, in adolescent boys.

METHODS

Seventy-eight healthy, slightly overweight 13- to 15-y-old boys were randomly assigned to breads with DHA-rich fish oil (1.1 g/d n-3 LCPUFA) or control for 16 wk. Whole-body bone mineral content (BMC), bone area (BA), bone mineral density (BMD), plasma osteocalcin, and growth factors were measured at wk 0 and wk 16, as well as diet, physical activity, and n-3 LCPUFA status in erythrocytes.

RESULTS

Fish oil strongly increased DHA status (P = 0.0001). No associations were found between DHA status and BMC, BA, BMD, or the markers of bone formation and growth at baseline. Furthermore, the fish oil intervention did not affect any of the outcomes as compared with control. However, dose-response analyses revealed a positive association between changes in DHA status and plasma insulin-like growth factor-1 (IGF-1) during intervention (β = 0.24, P = 0.03, n = 78).

DISCUSSION

DHA status and fish oil supplementation were not associated with bone mass or markers of bone formation in adolescent boys, but IGF-1 increased with increasing DHA status.

Human health effects of conjugated linoleic acid from milk and supplements

The primary purpose of the present review was to determine if the scientific evidence available for potential human health benefits of conjugated linoleic acid (CLA) is sufficient to support health claims on foods based on milk naturally enriched with cis-9, trans-11-CLA (c9, t11-CLA). A search of the scientific literature was conducted and showed that almost all the promising research results that have emerged in relation to cancer, heart health, obesity, diabetes and bone health have been in animal models or in vitro. Most human intervention studies have utilised synthetic CLA supplements, usually a 50:50 blend of c9, t11-CLA and trans-10, cis-12-CLA (t10, c12-CLA). Of these studies, the only evidence that is broadly consistent is an effect on body fat and weight reduction. A previous review of the relevant studies found that 3.2 g CLA/d resulted in a modest body fat loss in human subjects of about 0.09 kg/week, but this effect was attributed to the t10, c12-CLA isomer. There is no evidence of a consistent benefit of c9, t11-CLA on any health conditions; and in fact both synthetic isomers, particularly t10, c12-CLA, have been suspected of having pro-diabetic effects in individuals who are already at risk of developing diabetes. Four published intervention studies using naturally enriched CLA products were identified; however, the results were inconclusive. This may be partly due to the differences in the concentration of CLA administered in animal and human studies. In conclusion, further substantiation of the scientific evidence relating to CLA and human health benefits are required before health claims can be confirmed.

t10c12-CLA maintains higher bone mineral density during aging by modulating osteoclastogenesis and bone marrow adiposity

Conjugated linoleic acid (CLA) has been shown to positively influence calcium and bone metabolism. Earlier, we showed that CLA (equal mixture of c9t11-CLA and t10c12-CLA) could protect age-associated bone loss by modulating inflammatory markers and osteoclastogenesis. Since, c9t11-CLA and t10c12-CLA isomers differentially regulate functional parameters and gene expression in different cell types, we examined the efficacy of individual CLA isomers against age-associated bone loss using 12 months old C57BL/6 female mice fed for 6 months with 10% corn oil (CO), 9.5% CO + 0.5% c9t11-CLA, 9.5% CO + 0.5% t10c12-CLA or 9.5% CO + 0.25% c9t11-CLA + 0.25% t10c12-CLA. Mice fed a t10c12-CLA diet maintained a significantly higher bone mineral density (BMD) in femoral, tibial and lumbar regions than those fed CO and c9t11-CLA diets as measured by dual-energy-X-ray absorptiometry (DXA). The increased BMD was accompanied by a decreased production of osteoclastogenic factors, that is, RANKL, TRAP5b, TNF-alpha and IL-6 in serum. Moreover, a significant reduction of high fat diet-induced bone marrow adiposity was observed in t10c12-CLA fed mice as compared to that of CO and c9t11-CLA fed mice, as measured by Oil-Red-O staining of bone marrow sections. In addition, a significant reduction of osteoclast differentiation and bone resorbing pit formation was observed in t10c12-CLA treated RAW 264.7 cell culture stimulated with RANKL as compared to that of c9t11-CLA and linoleic acid treated cultures. In conclusion, these findings suggest that t10c12-CLA is the most potent CLA isomer and it exerts its anti-osteoporotic effect by modulating osteoclastogenesis and bone marrow adiposity.

Interaction between dietary conjugated linoleic acid and calcium supplementation affecting bone and fat mass

Dietary conjugated linoleic acid (CLA) has shown wide biologically beneficial effects, such as anticancer, antiatherosclerotic, antidiabetic, immunomodulating, and antiobesity effects. However, the effects of CLA on total body ash, reflective of bone mineral content, have not been consistent. We hypothesized that the inconsistency of the CLA effect on ash may be linked to interaction between CLA and dietary calcium levels. Thus, we investigated the effects of CLA on body ash in conjunction with various calcium levels. Male ICR mice were fed three different levels of calcium (0.01, 0.5, and 1%) with or without 0.5% CLA for 4 weeks for Experiment 1 and separate CLA isomers at 0.22% level with 1% calcium in Experiment 2. CLA feeding reduced body fat regardless of dietary calcium level, whereas CLA supplementation increased body ash compared to control only in animals fed the 1% calcium. In Experiment 2 it was confirmed that this observation was associated with the trans-10, cis-12 CLA isomer, but not with the cis-9, trans-11 isomer. CLA administration with 1% dietary calcium significantly improved total ash percent (%) in femurs, confirming that CLA has the potential to be used to improve bone mass.

Influence of high-fat diet from differential dietary sources on bone mineral density, bone strength, and bone fatty acid composition in rats

Previous studies have suggested that high-fat diets adversely affect bone development. However, these studies included other dietary manipulations, including low calcium, folic acid, and fibre, and (or) high sucrose or cholesterol, and did not directly compare several common sources of dietary fat. Thus, the overall objective of this study was to investigate the effect of high-fat diets that differ in fat quality, representing diets high in saturated fatty acids (SFA), n-3 polyunsaturated fatty acids (PUFA), or n-6 PUFA, on femur bone mineral density (BMD), strength, and fatty acid composition. Forty-day-old male Sprague-Dawley rats were maintained for 65 days on high-fat diets (20% by weight), containing coconut oil (SFA; n = 10), flaxseed oil (n-3 PUFA; n = 10), or safflower oil (n-6 PUFA; n = 11). Chow-fed rats (n = 10), at 105 days of age, were included to represent animals on a control diet. Rats fed high-fat diets had higher body weights than the chow-fed rats (p < 0.001). Among all high-fat groups, there were no differences in femur BMD (p > 0.05) or biomechanical strength properties (p > 0.05). Femurs of groups fed either the high n-3 or high n-6 PUFA diets were stronger (as measured by peak load) than those of the chow-fed group, after adjustment for significant differences in body weight (p = 0.001). As expected, the femur fatty acid profile reflected the fatty acid composition of the diet consumed. These results suggest that high-fat diets, containing high levels of PUFA in the form of flaxseed or safflower oil, have a positive effect on bone strength when fed to male rats 6 to 15 weeks of age.

Evaluation of body composition and cartilage biomarkers in large-breed dogs fed two foods designed for growth

OBJECTIVE

To evaluate cartilage and bone biomarkers and body composition in growing large-breed dogs consuming a diet designed for growth.

ANIMALS

43 large-breed 2 month-old-puppies.

PROCEDURES

Dogs were randomly assigned to receive 1 of 2 foods until 18 months of age. Dogs were evaluated at 2, 5, 12, and 18 months of age via dual energy x-ray absorptiometry (DEXA), CBC, serum biochemical profile, and concentrations or activities of taurine, vitamin E, fatty acids, glutathione peroxidase, C-propeptide of type II collagen (CPII), cartilage oligomeric matrix protein (COMP), carboxy-terminal cross-linked fragment of type II collagen (CTXII), bone specific alkaline phosphatase (BAP), osteocalcin, ghrelin, and growth hormone.

RESULTS

Blood components largely reflected the composition of the foods. Dogs fed the food with a higher concentration of protein, calcium, n-3 fatty acids, and antioxidants had a lower percentage of body fat and greater percentage of lean body mass at 5, 12, and 18 months of age, and higher CPII:CTXII ratio and lower COMP at 18 months of age. The BAP activity, osteocalcin concentration, and CTXII concentration declined with age, whereas COMP concentration and CPII concentration were similar at all time points for both foods.

CONCLUSIONS AND CLINICAL RELEVANCE

The BAP activity, osteocalcin concentration, and CTXII concentration were greater during growth than at 18 months of age. The food that was proportionately higher in protein, calcium, n-3 fatty acids, and antioxidants increased lean body mass and may have positively affected cartilage turnover as maturity was attained. Whether the rate of cartilage turnover during growth affects development of orthopedic disease or arthritis in adulthood has yet to be determined.

Long-term effects of gestational diabetes on offspring health are more pronounced in skeletal growth than body composition and glucose tolerance

Infants of diabetic mothers may have low arachidonic acid (AA) and develop obesity and insulin resistance in adulthood. The present study tested the effect of maternal diabetes and AA supplementation on offspring body composition, bone mass and glucose tolerance from 4 to 12 weeks. Rat dams were randomised into six groups using a 3 × 2 design. The rat dams were treated using the following treatments: saline-placebo, streptozotocin-induced diabetes (STZ) with glucose controlled at < 13 mmol/l (STZ/GC) or poorly controlled at 13-20 mmol/l (STZ/PC) using insulin, and fed either a control or an AA (0.5 % of fat) diet throughout reproduction. Weaned offspring were fed regular chow. Measurements included offspring body composition, bone and oral glucose tolerance testing (OGTT) plus liver fatty acids of dam and offspring. Comparable to saline-placebo offspring, the STZ/GC offspring had greater (P < 0.03) whole body and regional bone area than STZ/PC offspring. Maternal glucose negatively correlated (P < 0.05) with offspring whole body bone area and mineral content at 4 weeks in all offspring, and with tibia area in males at 12 weeks. Maternal liver DHA negatively (P < 0.03) correlated with femur and tibia mineral content and tibia mineral density of female offspring at 12 weeks. Offspring from AA-supplemented dams had higher (P = 0.004) liver AA at 4 weeks. Liver AA at 4 weeks positively (P = 0.05) correlated with lumbar spine mineral density in males. OGTT was not affected by maternal treatment or diet. These results suggest that maternal glucose control has long-term consequences to bone health of adult offspring. Skeletal growth appears more sensitive to maternal hyperglycaemia than glucose tolerance.

EFEITO DE FONTES MARINHAS RICAS EM PUFAs NA DIETA SOBRE A COMPOSIÇÃO LIPÍDICA E PERCENTUAIS DE INCORPORAÇÃO DE PUFAs n-6 NA GEMA DO OVO

RESUMO A presente pesquisa foi conduzida utilizando-se 288 galinhas poedeiras da linhagem Hisex White com 32 semanas de idade, pelo período de 10 semanas, com o objetivo de estudar o enriquecimento da gema do ovo em ácidos graxos a partir de rações suplementadas com óleo de peixe (OP) ou alga marinha (AM) em cinco níveis de ácido docosahexaenóico (DHA) de 120, 180, 240, 300 e 360 mg/100 g dieta. Foi aplicado o modelo fatorial 2 x 5, em delineamento inteiramente casualizado, com três repetições de oito aves por tratamento, de modo a constituir os grupos: OP120, OP180, OP240, OP300, OP360, AM120, AM180, AM240, AM300 e AM360. Um grupo controle submetido à ração basal de milho e soja (CON) e outro, acrescido de AM, contendo 420 mg de DHA/ 100 g dieta (AM420) foram também utilizados. Os ácidos araquidônico (AA), linoléico e PUFAs n-6 mostraram decréscimos significativos (P < 0,05) com o aumento de OP na dieta, variando, respectivamente, de 98,71 mg, 987,70 mg e 1.108,92 mg/gema na dieta CON a 38,87 mg, 734,22 mg e 802,79 mg/gema, para o grupo OP360. Para a fonte OP, as médias de AA também mostraram linearidade (Y = -0,16X + 89,40, R2 = 0,86), decrescendo de 98,71 mg/gema (CON) para 38,87 mg/ gema (OP360) e 77,79 mg/gema (AM420), enquanto que o total de PUFAs n-6 oscilou de 1.108,92 mg/gema (CON) a 802,79 mg/gema (OP360) e 1.178,19 mg/gema (AM120). O percentual de incorporação de AA na gema dos ovos decresceu linearmente com o aumento dos níveis de DHA na ração suplementada com OP e AM, de 4,81% (CON) para 2,57% (OP360) e 3,51% (AM420). As médias de 1.572,11 mg/gema (OP) e 2.118,16 mg/gema (AM) de consumo do total de PUFAs n6 e de 3,12% (OP) e 4,30% (AM) de incorporação de AA na gema diferiram (P < 0,05) entre fontes. Um decréscimo significativo (P < 0,05) foi consignado na relação n-6/n-3, variando de 17,50 (CON) para 3,72 (OP360) e 6,36 (AM420).

Effects of 9cis,11trans and 10trans,12cis CLA on osteoclast formation and activity from human CD14+ monocytes

Background

Mixed CLA isomers variably affect bone resorption in animals and decrease osteoclast formation and activity in murine osteoclasts. These variable effects may be due to the different isomers present in commercial preparations of CLA, and the effects of the predominant individual isomers, 9cis,11trans (9,11) and 10trans,12cis (10,12) CLA are not clear. The objectives of this study were to determine the effects of the individual CLA isomers on osteoclast formation and activity from human CD14⁺ monocytes, and to determine whether any changes are accompanied by changes in cathepsin K, matrix metalloproteinase-9 (MMP-9), receptor activator of NF-κB (RANK) and tumour necrosis factor alpha (TNFα) gene expression. Osteoclasts were identified as TRAP⁺ multinucleated cells. Osteoclast activity was quantified by the amount of TRAP in the cultured media.

Results

At 50 μM, 9,11 CLA inhibited osteoclast formation by ~70%, and both 9,11 and 10,12 CLA decreased osteoclast activity by ~85–90%. Both isomers inhibited cathepsin K (50 μM 9,11 by ~60%; 10,12 by ~50%) and RANK (50 μM 9,11 by ~85%; 50 μM 10,12 by ~65%) expression, but had no effect on MMP-9 or TNFα expression.

Conclusion

9,11 CLA inhibits osteoclast formation and activity from human cells, suggesting that this isomer may prevent bone resorption in humans. Although 10,12 CLA did not significantly reduce osteoclast formation, it reduced osteoclast activity and cathepsin K and RANK expression, suggesting that this isomer may also affect bone resorption.

Effects of arachidonic acid and docosahexaenoic acid on differentiation and mineralization of MC3T3-E1 osteoblast-like cells

Osteoblasts in culture can differentiate into mature mineralizing osteoblasts when stimulated with osteogenic agents. Clinical trials and in vivo animal studies suggest that specific polyunsaturated fatty acids (PUFAs) may benefit bone health. The aim of this study was to investigate whether arachidonic acid (AA) and docosahexaenoic acid (DHA) affect osteogenesis in osteoblasts and the transdifferentiation into adipocytes. Results from this study show that long-term exposure to AA inhibited alkaline phosphatase (ALP) activity in these cells, which might be prostaglandin E(2) (PGE(2))-mediated. DHA exposure also inhibited ALP activity which was evident after both short- and long-term exposures. The mechanism whereby DHA inhibits ALP activity is not clear and needs to be investigated. Although long-term exposure to PUFAs inhibited ALP activity, the mineralizing properties of these cells were not compromised. Furthermore, PUFA exposure did not induce adipocyte-like features in these cells as evidenced by the lack of cytoplasmic triacylglycerol accummulation. More research is required to elucidate the cellular mechanisms of action of PUFAs on bone.

Fatty acid pattern in serum is associated with bone mineralisation in healthy 8-year-old children

Animal studies have shown that fatty acids (FA) are important for normal bone development. Human data are scanty and mostly related to diseases. We hypothesised that serum FA pattern might be related to bone mineralisation in healthy children. Serum phospholipid FA pattern was studied in relation to bone parameters in eighty-five healthy Caucasian 8-year-olds. Dual-energy X-ray absorptiometry and blood sampling for analysis of serum phospholipid FA by capillary GLC were performed on the same day. SFA concentrations were associated with bone mineral density (BMD) of the hip, lumbar spine and total body. There was a general trend that linoleic acid (LA; 18 : 2n-6) was negatively associated with BMD, since that was found both for the LA concentration, the total n-6 concentration and the ratio of n-6:n-3 FA. Arachidonic acid (AA; 20 : 4n-6) was positively correlated with bone mineral content (BMC) and BMD of total body, as was the corresponding z-score and the AA:LA ratio. Both saturated and polyunsaturated serum phospholipid FA were associated with BMC and BMD in healthy children. LA and AA were found to inversely influence bone mineralisation and the association with the n-6:n-3 ratio suggested that this balance might also be of importance. The general trend of a negative influence of high n-6 FA concentrations on bone mineralisation might be of concern in relation to the changes in the Western diet. Longitudinal studies are necessary to verify if different bone compartments and different grades of modelling are related to different FA patterns.