Effect of the types of dietary fats and non-dietary oils on bone metabolism

Association between serum polyunsaturated fatty acids and bone mineral density in US adults: NHANES 2011-2014

Objective

The purpose of this study was to investigate the association between serum polyunsaturated fatty acids (PUFAs) and bone mineral density (BMD).

Methods

We performed a cross-sectional study based on data from the National Health and Nutrition Examination Survey (NHANES) 2011-2014. The weighted multiple linear regression model was utilized to determine the association between serum PUFAs and BMD. Further smoothed curve fitting and threshold effect analysis were conducted. Finally, we performed a subgroup analysis.

Results

In total, 1979 participants aged 20-59 years were enrolled. After adjusting for all covariates, we found that serum docosapentaenoic acid (DPA) was positively associated with head BMD (β = 0.0015, 95% Cl: 0.0004, 0.0026, P = 0.008296) and lumbar spine BMD (β = 0.0005, 95% Cl: 0.0000, 0.0010, P = 0.036093), and serum eicosadienoic acid (EDA) was negatively associated with thoracic spine BMD (β = -0.0008, 95% Cl: -0.0016, -0.0000, P = 0.045355). Smoothed curve fitting revealed a nonlinear positive association between serum DPA and lumbar spine BMD. Threshold effect analysis indicated that the threshold of serum DPA was 81.4 µmol/L. Subgroup analysis revealed a positive correlation between serum DPA and head BMD in the subgroup aged 50-59 years (β = 0.0025, 95% Cl: 0.0002, 0.0049, P = 0.035249) and females (β = 0.0026, 95% Cl: 0.0008, 0.0044, P = 0.005005). There was a positive relationship between serum DPA and lumbar spine BMD in females (β = 0.0008, 95% Cl: 0.0001, 0.0015, P = 0.017900) and a negative association between serum EDA and thoracic spine BMD in the subgroup aged 30-39 years (β = -0.0016, 95% Cl: -0.0031, -0.0001, P = 0.041331), males (β = -0.0012, 95% Cl: -0.0023, -0.0001, P = 0.039364) and other races (β = -0.0021, 95% Cl: -0.0037, -0.0006, P = 0.008059).

Conclusion

This study demonstrated a linear positive relationship between serum DPA and head BMD, a nonlinear positive association between serum DPA and lumbar spine BMD, and a linear negative correlation between serum EDA and thoracic spine BMD in US adults.

Associations between Macronutrients Intake and Bone Mineral Density: A Longitudinal Analysis of the Health Workers Cohort Study Participants

OBJECTIVE

This study aimed to evaluate the association between macronutrient intake and bone mineral density (BMD) using non-substitution and substitution statistical approaches.

DESIGN

Longitudinal analysis.

SETTINGS AND PARTICIPANTS

1,317 adults in the Health Worker Cohort Study in Mexico.

MEASUREMENTS

These participants were assessed at baseline (2004-2006) and follow-up (2010-2012). Dietary intakes were assessed using validated food frequency questionnaires. BMD at the different sites was performed by dual-energy X-ray absorptiometry (DXA). Hybrid-mixed effects regression models were performed to evaluate the associations of interest.

RESULTS

Cross-sectional associations were found between fiber intake and higher total hip and femoral neck BMD in women and longitudinal associations with loss of femoral neck BMD in men. An increase in 5% energy intake from carbohydrate was associated with a BMD loss at several site in women and total hip and femoral neck in men. In both sexes, an increase in 5% energy intake of animal protein or fat was associated with a site-specific BMD gain after six years. Substitution analysis showed that the energy intake replacement from fat or carbohydrate by protein had an increase in BMD at different sites in women; while in men, it was only significant when replacing carbohydrate. Substitution of protein or fat by carbohydrates was associated with lower BMD in women, and only protein replacement by carbohydrates in men.

CONCLUSION

Our findings suggest that carbohydrate intake was associated with loss of BMD, while animal protein and fat intake was associated with gain of BMD among the Mexican population. Macronutrient substitutions resulted in significant associations; however, additional studies are needed to confirm these findings.

Beneficial effects of monounsaturated fatty acid-rich blended oils with an appropriate polyunsaturated/saturated fatty acid ratio and a low n-6/n-3 fatty acid ratio on the health of rats

BACKGROUND

The effects of dietary fat on health are influenced by its fatty acid profile. We aimed to determine the effects of monounsaturated fatty acid (MUFA)-rich blended oils (BO) containing a balance of polyunsaturated fatty acids (PUFAs) and saturated fatty acids (SFAs) and with a low n-6/n-3 PUFA ratio on the health of rats fed normal or high-fat diets. The BO was obtained by mixing red palm oil, rice bran oil (RO), tea seed oil and flaxseed oil in appropriate proportions.

RESULTS

BO consumption reduced the serum low-density lipoprotein cholesterol (LDL-C), non-esterified fatty acid (NEFA), insulin (INS), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1 (IL-1), high-sensitivity C-reactive protein (hs-CRP), malondialdehyde (MDA), lipid peroxide (LPO) and oxidized LDL (ox-LDL) concentrations and the homeostasis model assessment of insulin resistance (HOMA-IR); it increased the high-density lipoprotein cholesterol (HDL-C), glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) concentrations, and the bone mineral density (BMD) versus control oil-containing normal and high-fat diets. BO also reduced the triglyceride (TG), hs-CRP, MDA, ox-LDL and reactive oxygen species (ROS) concentrations; and increased the serum HDL-C and SOD, and BMD versus RO-containing high-fat diets. Finally, BO reduced the glucose (GLU) and INS, and HOMA-IR; it increased HDL-C, SOD, femoral weight and BMD versus RO-containing normal diets.

CONCLUSION

BOs with an appropriate fatty acid profile have beneficial effects on the glucolipid metabolism, inflammation, oxidative stress and bone quality of rats when included in both normal and high-fat diets. © 2022 Society of Chemical Industry.

Targeting NRF2-KEAP1 axis by Omega-3 fatty acids and their derivatives: Emerging opportunities against aging and diseases

The transcription factor NRF2 and its endogenous inhibitor KEAP1 play a crucial role in the maintenance of cellular redox homeostasis by regulating the gene expression of diverse networks of antioxidant, anti-inflammatory, and detoxification enzymes. Therefore, activation of NRF2 provides cytoprotection against numerous pathologies, including age-related diseases. An age-associated loss of NRF2 function may be a key driving force behind the aging phenotype. Recently, numerous NRF2 inducers have been identified and some of them are promising candidates to restore NRF2 transcriptional activity during aging. Emerging evidence indicates that omega-3 (n-3) polyunsaturated fatty acids (PUFAs) and their electrophilic derivatives may trigger a protective response via NRF2 activation, rescuing or maintaining cellular redox homeostasis. In this review, we provide an overview of the NRF2-KEAP1 system and its dysregulation in aging cells. We also summarize current studies on the modulatory role of n-3 PUFAs as potential agents to prevent multiple chronic diseases and restore the age-related impairment of NRF2 function.

Probiotics Lactobacillus rhamnosus GG ATCC53103 and Lactobacillus plantarum JL01 induce cytokine alterations by the production of TCDA, DHA, and succinic and palmitic acids, and enhance immunity of weaned piglets

Probiotics, including Lactobacillus rhamnosus GG ATCC53103 and Lactobacillus plantarum JL01, can improve growth performance and immunity of piglets, and relieve weaning stress-related immune disorders such as intestinal infections and inflammation. This study aimed to evaluate the ability of co-administration of the probiotics L. rhamnosus GG ATCC53103 and L. plantarum JL01 to stimulate immune responses and improve gut health during the critical weaning period in piglets. Forty-eight weaned piglets were randomly divided into four groups, and fed daily for 28 days either without, or with the two probiotics independently, or in combination. On day 28, we analyzed the cytokine and bacterial changes in intestinal mucosa and the hepatic portal vein blood metabolites of the weaned piglets. Our results showed that combined L. rhamnosus GG ATCC53103 and L. plantarum JL01 significantly increased (p < 0.05) the growth performance and expression of IL-10 and TGF-β1 mRNAs. In contrast, this treatment significantly decreased (p < 0.05) IL-1β mRNA level in the jejunum, ileum, and cecum. Furthermore, the secretion of IL-6 in the cecum, IL-1β in the jejunum, ileum, and cecum, and TNF-α in the jejunum and ileum was significantly decreased (p < 0.05). The relative abundance of Prevotella_9 and Enterococcus in ileum and cecum was significantly increased (p < 0.05). The relative abundance of Ruminococcus_1 and Ruminococcaceae_UCG-005 in cecum was significantly decreased (p < 0.05). Prevotella_9 and Enterococcus may increase the accumulation of (4Z,7Z,10Z,13Z,16Z,19Z)-4,7,10,13,16,19-docosahexaenoic acid (DHA) and tauroursodeoxycholic acid (TCDA) in portal vein blood, while Ruminococcus_1 and Ruminococcaceae_UCG-005 may decrease the accumulation of succinic and palmitic acids. These results indicate that L. rhamnosus GG ATCC53103 and L. plantarum JL01 may regulate cytokine levels by reducing the accumulation of succinic and palmitic acids and increasing the accumulation of TCDA and DHA, thereby enhancing the immunity of weaned piglets.

Flaxseed extract induces apoptosis in human breast cancer MCF-7 cells

Significant evidence indicated that flaxseed (Linum usitatissimum) possesses various positive health aspects such as reducing the risk of cancer and cardiovascular diseases. The fatty acids are considered to be responsible for these benefits of flaxseed. Herein, the in vitro effects of flaxseed extract on the growth and apoptosis of human breast cancer MCF-7 cells were investigated. The MCF-7 cells treated with flaxseed extract showed a dose-dependent decrease in cell viability. The flaxseed extract induced reactive oxygen species and the flow cytometric analysis demonstrated that flaxseed fatty acids triggered apoptosis of MCF-7 cells, which was also shown by the loss of mitochondrial membrane potential and caspase cascade reaction. Thus, the flaxseed extract regulated the growth of MCF-7 cells and induced apoptosis. Eventually, the flaxseed could be used as a dietary supplement to prevent breast cancer.

Impacts of Psychological Stress on Osteoporosis: Clinical Implications and Treatment Interactions

The significant biochemical and physiological effects of psychological stress are beginning to be recognized as exacerbating common diseases, including osteoporosis. This review discusses the current evidence for psychological stress-associated mental health disorders as risk factors for osteoporosis, the mechanisms that may link these conditions, and potential implications for treatment. Traditional, alternative, and adjunctive therapies are discussed. This review is not intended to provide therapeutic recommendations, but, rather, the goal of this review is to delineate potential interactions of psychological stress and osteoporosis and to highlight potential multi-system implications of pharmacological interventions. Review of the current literature identifies several potentially overlapping mechanistic pathways that may be of interest (e.g., glucocorticoid signaling, insulin-like growth factor signaling, serotonin signaling) for further basic and clinical research. Current literature also supports the potential for cross-effects of therapeutics for osteoporosis and mental health disorders. While studies examining a direct link between osteoporosis and chronic psychological stress are limited, the studies reviewed herein suggest that a multi-factorial, personalized approach should be considered for improved patient outcomes in populations experiencing psychological stress, particularly those at high-risk for development of osteoporosis.

Omega-3 and omega-6 polyunsaturated fatty acids: Dietary sources, metabolism, and significance - A review

Linoleic acid (LA) (n-6) and α-linolenic acid (ALA) (n-3) are essential fatty acids (EFAs) as they cannot be synthesized by humans or other higher animals. In the human body, these fatty acids (FAs) give rise to arachidonic acid (ARA, n-6), eicosapentaenoic acid (EPA, n-3), and docosahexaenoic acid (DHA, n-3) that play key roles in regulating body homeostasis. Locally acting bioactive signaling lipids called eicosanoids derived from these FAs also regulate diverse homeostatic processes. In general, ARA gives rise to pro-inflammatory eicosanoids whereas EPA and DHA give rise to anti-inflammatory eicosanoids. Thus, a proportionally higher consumption of n-3 PUFAs can protect us against inflammatory diseases, cancer, cardiovascular diseases, and other chronic diseases. The present review summarizes major sources, intake, and global consumption of n-3 and n-6 PUFAs. Their metabolism to biosynthesize long-chain PUFAs and eicosanoids and their roles in brain metabolism, cardiovascular disease, obesity, cancer, and bone health are also discussed.