Conjugated linoleic acid (CLA) promotes endurance capacity via peroxisome proliferator-activated receptor δ-mediated mechanism in mice

Erucic Acid: A Possible Therapeutic Agent for Neurodegenerative Diseases

Neurodegenerative disorders are among the most common life-threatening disorders among the elderly worldwide and are marked by neuronal death in the brain and spinal cord. Several studies have demonstrated the beneficial role of dietary fatty acids in different brain disorders. This is due to their neurotrophic, antioxidant, and anti-inflammatory properties. Furthermore, extensive evidence shows that an unbalanced intake of certain dietary fatty acids increases the risk of neuropsychiatric diseases. Several research has been done on erucic acid, an ingestible omega-9 fatty acid that is found in Lorenzo's oil. Erucic acid was previously thought to be a natural toxin because of its negative effects on heart muscle function and hepatic steatosis, but it has been discovered that erucic acid is regularly consumed in Asian countries through the consumption of cruciferous vegetables like mustard and rapeseed oil with no evidence of cardiac harm. Erucic acid can also be transformed into nervonic acid, a crucial element of myelin. Therefore, erucic acid may have remyelinating effects, which may be crucial for treating different demyelinating conditions. Also, erucic acid exerts antioxidant and anti-inflammatory effects, suggesting its possible therapeutic role in different neurodegenerative disorders. Considering the fruitful effects of this compound, this article reviews the probable role of erucic acid as a pharmacological agent for treating and managing different neurodegenerative disorders.

Conjugated linoleic acid (CLA) as a functional food: Is it beneficial or not?

Conjugated linoleic acid (CLA) has attracted great attention in recent years as a popular class of functional food that is broadly used. It refers to a group of geometric and positional isomers of linoleic acid (LA) with a conjugated double bond. The main natural sources of CLA are dairy products, beef and lamb, whereas only trace amounts occur naturally in plant lipids. CLA has been shown to improve various health issues, having effects on obesity, inflammatory, anti-carcinogenicity, atherogenicity, immunomodulation, and osteosynthesis. Also, compared to studies on humans, many animal researches reveal more positive benefits on health. CLA represents a nutritional avenue to improve lifestyle diseases and metabolic syndrome. Most of these effects are attributed to the two major CLA isomers [conjugated linoleic acid cis-9,trans-11 isomer (c9,t11), and conjugated linoleic acid trans-10,cis-12 isomer (t10,c12)], and their mixture (CLA mix). In contrast, adverse effects of CLA have been also reported, such as glucose homeostasis, insulin resistance, hepatic steatosis and induction of colon carcinogenesis in humans, as well as milk fat inhibition in ruminants, lowering chicken productivity, influencing egg quality and altering growth performance in fish. This review article aims to discuss the health benefits of CLA as a nutraceutical supplement and highlight the possible mechanisms of action that may contribute to its outcome. It also outlines the feasible adverse effects of CLA besides summarizing the recent peer-reviewed publications on CLA to ensure its efficacy and safety for proper application in humans.

Mitochondrial Adaptive Responses to Hypertriglyceridemia and Bioactive Lipids

Significance: Altered plasma triglyceride metabolism and changes in dietary fatty acid types and levels are major contributors to the development of metabolic and cardiovascular diseases such as fatty liver disease, obesity, diabetes, and atherosclerosis. Lipid accumulation in visceral adipose tissue and ectopically in other organs, as well as lipid-induced redox imbalance, is connected to mitochondrial dysfunction in a range of oxidative stress-associated metabolic and degenerative disorders. Recent Advances: Successful mitochondrial adaptive responses in the context of hypertriglyceridemia and dietary bioactive polyunsaturated fatty acids contribute to increase body energy expenditure and reduce oxidative stress, thus allowing several cell types to cope with metabolic challenges and stresses. These responses include mitochondrial redox signaling, mild uncoupling, and changes in network dynamic behavior. Critical Issues: Mitochondrial bioenergetics and redox changes in a lipid overload context are relatively well characterized. However, the turning point between adaptive and maladaptive mitochondrial responses remains a critical issue to be elucidated. In addition, the relationship between changes in fusion/fission machinery and mitochondrial function is less well understood. Future Directions: The effective mitochondrial responses described here support the research for new drug design and diet or nutraceutical formulations targeting mitochondrial mild uncoupling and effective quality control as putative strategies for cardiometabolic diseases. Antioxid. Redox Signal. 36, 953-968.

Effects of conjugated linoleic acid on growth performance, nutrient digestibility and blood biochemical indexes of male sika deer (Cervus nippon)

ContextConjugated linoleic acid (CLA) is very important for animals and humans. CLA has many important biological functions, such as reducing fat and increasing muscle, antioxidation, improving immunity and so on. CLA requirements for deer have not been established.AimsA single-factor test was conducted to evaluate the effects of CLA supplementation on male sika deer.MethodsSixteen deer were divided in four groups (from G0 to G3) of four animals, each according to their bodyweight. Deer in G0 were fed a basal diet without CLA supplementation. Deer in G1, G2 and G3 were fed diets supplemented with CLA at concentrations of 0.25%, 0.5% and 1.0%. Growth performance, nutrient digestibility and blood biochemical indexes were measured.Key resultsThe results suggested that the average daily gain of deer increased with conjugated linoleic acid supplementation (P<0.05); maximal growth performance was seen in G2. The average daily feed intake showed differences among the treatments (P<0.01). The highest average daily feed intake was observed in Group G2. Feed to gain ratio (F:G) in Groups G1, G2 and G3 was different from that in Group G0 (P<0.01). The digestibility of crude protein and ether extract was increased by conjugated linoleic acid concentrations (P<0.05). The alkaline phosphatase activity showed a significant increase (P<0.05) in Groups G2 and G3, compared with Group G0. There were significant differences in cholesterol between G1 and G2 groups (P<0.05).ConclusionsThe results indicated that conjugated linoleic acid supplementation to diet plays a positive role in the growth of sika deer.ImplicationsThis experiment has shown the effects of dietary supplementation with CLA in sika deer breeding. It has layed a good foundation for the application of CLA supplementation in sika deer industry to promote the healthy development of sika deer breeding industry.

trans 10, cis 12, but Not cis 9, trans 11 Conjugated Linoleic Acid Isomer Enhances Exercise Endurance by Increasing Oxidative Skeletal Muscle Fiber Type via Toll-like Receptor 4 Signaling in Mice

Conjugated linoleic acid (CLA) has been implicated in regulating muscle fiber. However, which isomer elicits this effect and the underlying mechanisms remain unclear. Here, male C57BL6/J mice and C2C12 cells were treated with two CLA isomers, and the exercise endurance, skeletal muscle fiber type, and involvement of Toll-like receptor 4 (TLR4) signaling were assessed. The results demonstrated that dietary t10, c12, but not c9, t11-CLA isomer enhanced exercise endurance of mice (from 115.88 ± 11.21 to 130.00 ± 15.84 min, P < 0.05) and promoted the formation of oxidative muscle fiber type of gastrocnemius muscle (from 0.15 ± 0.04 to 0.24 ± 0.05, P < 0.05). Consistently, t10, c12-CLA isomer increased the mRNA expression of oxidative muscle fiber type in C2C12 myotubes (from 1.00 ± 0.08 to 2.65 ± 1.77, P < 0.05). In addition, t10, c12-CLA isomer increased TLR4 signaling expression in skeletal muscle and C2C12 myotubes. More importantly, knockdown of TLR4 eliminated the t10, c12-CLA isomer-induced enhancement of exercise endurance in mice and elevation of oxidative muscle fiber type in C2C12 myotubes and gastrocnemius muscle. Together, these findings showed that t10, c12, but not c9, t11-CLA isomer enhances exercise endurance by increasing oxidative skeletal muscle fiber type via TLR4 signaling.

Physiologically Active Molecules and Functional Properties of Soybeans in Human Health-A Current Perspective

In addition to providing nutrients, food can help prevent and treat certain diseases. In particular, research on soy products has increased dramatically following their emergence as functional foods capable of improving blood circulation and intestinal regulation. In addition to their nutritional value, soybeans contain specific phytochemical substances that promote health and are a source of dietary fiber, phospholipids, isoflavones (e.g., genistein and daidzein), phenolic acids, saponins, and phytic acid, while serving as a trypsin inhibitor. These individual substances have demonstrated effectiveness in preventing chronic diseases, such as arteriosclerosis, cardiac diseases, diabetes, and senile dementia, as well as in treating cancer and suppressing osteoporosis. Furthermore, soybean can affect fibrinolytic activity, control blood pressure, and improve lipid metabolism, while eliciting antimutagenic, anticarcinogenic, and antibacterial effects. In this review, rather than to improve on the established studies on the reported nutritional qualities of soybeans, we intend to examine the physiological activities of soybeans that have recently been studied and confirm their potential as a high-functional, well-being food.

Dietary conjugated linoleic acid supplementation alters skeletal muscle mitochondria and antioxidant status in young horses

Conjugated linoleic acid (CLA) improves oxidative stress and mitochondrial biogenesis in various species but has not been thoroughly investigated in horses. We collected blood and muscle samples from lightly exercising horses before and 6 and 12 wk after receiving either soybean oil (CON; n = 5) or CLA (CLA; n = 5) supplementation. Samples were analyzed for markers of mitochondrial characteristics, antioxidant status, oxidative stress, and muscle damage. Data were analyzed using a linear model with repeated measures. In the triceps brachii (TB), citrate synthase (CS) activity was higher in CON than CLA horses (P = 0.003) but was unaffected by diet in the gluteus medius (GM). Integrative (relative to mg protein) cytochrome c oxidase (CCO) activity was higher in TB than the GM (P < 0.0001), while intrinsic (relative to CS) CCO was lower in the TB than the GM (P = 0.02) and tended to be lower in CON than CLA horses (P = 0.06). Neither CS nor integrative CCO activities were affected by time. In the GM, superoxide dismutase activity tended to increase in CON through week 12 (P = 0.10). Over both muscle groups, glutathione peroxidase activity tended to be higher in CON compared with CLA at week 12 (P = 0.06). Malondialdehyde was higher in the TB than the GM (P = 0.0004) but was unaffected by diet, while serum creatine kinase activity tended to be lower in CLA than CON horses (P = 0.07). These results suggest that CLA supplementation may lead to mitochondrial adaptations and prevent myofiber perturbation in skeletal muscle of young, lightly exercised horses.

Adaptations of Skeletal Muscle Mitochondria to Obesity, Exercise, and Polyunsaturated Fatty Acids

Mitochondria intricately modulate their energy production through the control of mitochondrial adaptation (mitochondrial biogenesis, fusion, and/or fission) to meet energy demands. Nutrient overload may result in dysregulated mitochondrial biogenesis, morphology toward mitochondrial fragmentation, and oxidative stress in the skeletal muscle. In addition, physical activity and diet components influence mitochondrial function. Exercise may stimulate mitochondrial biogenesis and promote mitochondrial fusion/fission in the skeletal muscle. Moreover, some dietary fatty acids, such as n-3 polyunsaturated fatty acids and conjugated linoleic acid, have been identified to positively regulate mitochondrial adaptation in the skeletal muscle. This review discusses the association of mitochondrial impairments and obesity, and presents an overview of various mechanisms of which exercise training and mitochondrial nutrients promote mitochondrial function in the skeletal muscle.

Effects of conjugated linoleic acid (CLA) on fat accumulation, activity, and proteomics analysis in Caenorhabditis elegans

Conjugated linoleic acid (CLA) has been reported to reduce fat storage in cell culture and animal models. In the current study, the effects of CLA on the fat accumulation, activities, and proteomics were investigated using Caenorhabditis elegans. 100 µM CLA-TG nanoemulsion significantly reduced fat accumulation by 29% compared to linoleic acid (LA)-TG treatment via sir-2.1 (the ortholog of Sirtuin 1), without altering the worm size, growth rate, and pumping rate of C. elegans. CLA significantly increased moving speed and amplitude (the average centroid displacement over the entire track) of wild type worms compared to the LA group and these effects were dependent on aak-2 (AMPKα ortholog) and sir-2.1. Proteomics analysis showed CLA treatment influences various proteins associated in reproduction and development, translation, metabolic processes, and catabolism and proteolysis, in C. elegans. We have also confirmed the proteomics data that CLA reduced the fat accumulation via abs-1 (ATP Synthase B homolog). However, there were no significant effects of CLA on brood size, progeny numbers, and hatchability compared to LA treatment.

Periodized Nutrition for Athletes

It is becoming increasingly clear that adaptations, initiated by exercise, can be amplified or reduced by nutrition. Various methods have been discussed to optimize training adaptations and some of these methods have been subject to extensive study. To date, most methods have focused on skeletal muscle, but it is important to note that training effects also include adaptations in other tissues (e.g., brain, vasculature), improvements in the absorptive capacity of the intestine, increases in tolerance to dehydration, and other effects that have received less attention in the literature. The purpose of this review is to define the concept of periodized nutrition (also referred to as nutritional training) and summarize the wide variety of methods available to athletes. The reader is referred to several other recent review articles that have discussed aspects of periodized nutrition in much more detail with primarily a focus on adaptations in the muscle. The purpose of this review is not to discuss the literature in great detail but to clearly define the concept and to give a complete overview of the methods available, with an emphasis on adaptations that are not in the muscle. Whilst there is good evidence for some methods, other proposed methods are mere theories that remain to be tested. 'Periodized nutrition' refers to the strategic combined use of exercise training and nutrition, or nutrition only, with the overall aim to obtain adaptations that support exercise performance. The term nutritional training is sometimes used to describe the same methods and these terms can be used interchangeably. In this review, an overview is given of some of the most common methods of periodized nutrition including 'training low' and 'training high', and training with low- and high-carbohydrate availability, respectively. 'Training low' in particular has received considerable attention and several variations of 'train low' have been proposed. 'Training-low' studies have generally shown beneficial effects in terms of signaling and transcription, but to date, few studies have been able to show any effects on performance. In addition to 'train low' and 'train high', methods have been developed to 'train the gut', train hypohydrated (to reduce the negative effects of dehydration), and train with various supplements that may increase the training adaptations longer term. Which of these methods should be used depends on the specific goals of the individual and there is no method (or diet) that will address all needs of an individual in all situations. Therefore, appropriate practical application lies in the optimal combination of different nutritional training methods. Some of these methods have already found their way into training practices of athletes, even though evidence for their efficacy is sometimes scarce at best. Many pragmatic questions remain unanswered and another goal of this review is to identify some of the remaining questions that may have great practical relevance and should be the focus of future research.

Roles of Peroxisome Proliferator-Activated Receptor β/δ in skeletal muscle physiology

More than two decades of studying Peroxisome Proliferator-Activated Receptors (PPARs) has led to an understanding of their implications in various physiological processes that are key for health and disease. All three PPAR isotypes, PPARα, PPARβ/δ, and PPARγ, are activated by a variety of molecules, including fatty acids, eicosanoids and phospholipids, and regulate a spectrum of genes involved in development, lipid and carbohydrate metabolism, inflammation, and proliferation and differentiation of many cell types in different tissues. The hypolipidemic and antidiabetic functions of PPARα and PPARγ in response to fibrate and thiazolidinedione treatment, respectively, are well documented. However, until more recently the functions of PPARβ/δ were less well defined, but are now becoming more recognized in fatty acid metabolism, energy expenditure, and tissue repair. Skeletal muscle is an active metabolic organ with high plasticity for adaptive responses to varying conditions such as fasting or physical exercise. It is the major site of energy expenditure resulting from lipid and glucose catabolism. Here, we review the multifaceted roles of PPARβ/δ in skeletal muscle physiology.