Marine n-3 polyunsaturated fatty acids: a potential role in the treatment of sarcopenia

Key nutrients important in the management of canine myxomatous mitral valve disease and heart failure

The most common cause of heart failure in dogs is myxomatous mitral valve disease (MMVD), which accounts for approximately 75% of canine heart disease cases and is especially common in smaller dogs. Although low-sodium diets have been recommended for humans with heart diseases for decades, there is little evidence to support this practice in dogs. In recent years, however, it has become clear that other nutrients are important to heart health. Dogs with heart disease secondary to MMVD experience patterns of metabolic changes that include decreased mitochondrial energy metabolism and ATP availability, with increased oxidative stress and inflammation. These changes occur early in disease and progress with worsening heart disease. Key nutrients that may support normal function and address these changes include omega-3 fatty acids, medium-chain triglycerides, magnesium, antioxidants including vitamin E and taurine, and the amino acids methionine and lysine. The long-chain omega-3 fatty acids provide anti-inflammatory, antithrombotic, and other benefits. Medium-chain fatty acids and ketones derived from medium-chain triglycerides provide an alternative energy source for cardiac mitochondria and help reduce free radical production. Magnesium supports mitochondrial function, normal cardiac rhythm, and provides other benefits. Both vitamin E and taurine counter oxidative stress, and taurine also has direct cardiac benefits. Dogs with MMVD have reduced plasma methionine. Methionine and lysine are important for carnitine production as well as other functions. This article reviews the evidence supporting the functions and benefits of these and other nutrients in MMVD and other cardiac conditions.

Factors associated with sarcopenia: A cross-sectional analysis using UK Biobank

INTRODUCTION

The critical sociodemographic, lifestyle and diseases factors influencing sarcopenia, defined by the current European Working Group on Sarcopenia 2 (EWGSOP2) classification and cut-off points, have not yet been fully elucidated. This study aimed, therefore, to determine sociodemographic, anthropometric, lifestyle and health-related factors associated with sarcopenia using the new EWGSOP2 definition.

STUDY DESIGN

396,283 participants (52.8 % women, age 38-73 years) were included in this cross-sectional study. The potential factors associated with sarcopenia were allocated to four categories: sociodemographic (sex, age, education, income and professional qualification), anthropometric (nutritional status, abdominal obesity, body fat and birth weight), lifestyle (physical activity, smoking, sleeping, sitting time, TV viewing, alcohol, and dietary intakes) and health status (self-reported prevalent diseases). P-values were corrected for multiple testing using the Bonferroni method.

RESULTS

Age, women, lower education, higher deprivation, underweight, lower birth weight, and chronic diseases such as rheumatoid arthritis, chronic bronchitis and osteoporosis were associated with a higher likelihood of sarcopenia. Conversely, overweight, obesity, as well as a self-reported higher intake of energy, protein, vitamins (B12 and B9) and minerals (potassium, calcium and magnesium) were associated with lower odds of sarcopenia.

CONCLUSION

Women, people aged over 65 years, underweight people and those with rheumatoid arthritis were most likely to have sarcopenia. Considering the increase in the ageing population, sarcopenia is likely to become more prevalent. Identifying factors associated with sarcopenia could inform future strategies for early identification of individuals at high risk of sarcopenia and therefore the implementation of preventive strategies against the disease.

Response to exercise in older adults who take supplements of antioxidants and/or omega-3 polyunsaturated fatty acids: A systematic review

BACKGROUND

Nutrition is a key factor in determining exercise response. The aim of this review is to assess the response to exercise in older adults who take supplements of antioxidants and/or omega-3 polyunsaturated fatty acids.

METHODS

A systematic literature search was performed (June 2009- September 2019) in MEDLINE via Pubmed. The following search strategy was used with Boolean markers: ("omega-3 fatty acids" [Major] OR "antioxidants" [Major]) AND "exercise" AND "aged" [MesH]. Fourteen articles were finally included.

RESULTS

Exercise-induced free radical and inflammatory marker blood levels, but not changed the plasma total antioxidant capacity (TAC), after administration of antioxidant supplement. The oral administration of antioxidants produced null or negative effect on endothelial function, but the infusion into the brachial artery during rhythmic handgrip exercise produced a significant improvement in muscle blood flow, due to an on increase in the availability of nitric acid derived from the nitric oxide synthase. Aerobic exercise and antioxidant supplementation improved submaximal and maximal aerobic parameters, as well as mitochondrial density and mitochondria-regulated apoptotic signaling. Antioxidant supplementation, but not omega-3 PUFA, decreased pro-inflammatory marker levels and fat oxidation induced by exercise. Strength training decreased serum B₁₂ concentration but combined with omega-3 PUFA or antioxidant supplementation, B₁₂ levels were maintained. Antioxidant supplementation has protective effect after fatigue in isometric exercise but improved appendicular fat-free mass just combined with resistance exercise. Omega-3 fatty acid supplement combined with exercise increased lean mass in women, but not in men. Muscle damage induced by exercise is protected by antioxidant supplementation.

CONCLUSIONS

Older people who take antioxidant and/or omega-3 PUFA supplements showed improved exercise response, as well as lower muscle damage.