Soft, Tough, Antifatigue Fracture Elastomer Composites with Low Thermal Resistance through Synergistic Crack Pinning and Interfacial Slippage.

Soft elastomer composites are promising functional materials for engineer interfaces, where the miniaturized electronic devices have triggered increasing demand for effective heat dissipation, high fracture energy, and antifatigue fracture. However, such a combination of these properties can be rarely met in the same elastomer composites simultaneously. Here a strategy is presented to fabricate a soft, extreme fracture tough (3316 J m-2) and antifatigue fracture (1052.56 J m⁻2) polydimethylsiloxane/aluminum elastomer composite. These outstanding properties are achieved by optimizing the dangling chains and spherical aluminum fillers, resulting in the combined effects of crack pinning and interfacial slippage. The dangling chains that lengthen the polymer chains between cross-linked points pin the cracks and the rigid fillers obstruct the cracks, enhancing the energy per unit area needed for fatigue failure. The dangling chains also promote polymer/filler interfacial slippage, enabling effective deflection and blunting of an advancing crack tip, thus enhancing mechanical energy dissipation. Moreover, the elastomer composite exhibits low thermal resistance (≈0.12 K cm2 W-1), due to the formation of a thermally conductive network. These remarkable characteristics render this elastomer composite promising for application as a thermal interface material in electronic devices.

Systematical Investigation on Anti-Fatigue Function and Underlying Mechanism of High Fischer Ratio Oligopeptides from Antarctic Krill on Exercise-Induced Fatigue in Mice.

High Fischer ratio oligopeptides (HFOs) have a variety of biological activities, but their mechanisms of action for anti-fatigue are less systematically studied at present. This study aimed to systematically evaluate the anti-fatigue efficacy of HFOs from Antarctic krill (HFOs-AK) and explore its mechanism of action through establishing the fatigue model of endurance swimming in mice. Therefore, according to the comparison with the endurance swimming model group, HFOs-AK were able to dose-dependently prolong the endurance swimming time, reduce the levels of the metabolites (lactic acid, blood urea nitrogen, and blood ammonia), increase the content of blood glucose, muscle glycogen, and liver glycogen, reduce lactate dehydrogenase and creatine kinase extravasation, and protect muscle tissue from damage in the endurance swimming mice. HFOs-AK were shown to enhance Na+-K+-ATPase and Ca2+-Mg2+-ATPase activities and increase ATP content in muscle tissue. Meanwhile, HFOs-AK also showed significantly antioxidant ability by increasing the activities of superoxide dismutase and glutathione peroxidase in the liver and decreasing the level of malondialdehyde. Further studies showed that HFOs-AK could regulate the body's energy metabolism and thus exert its anti-fatigue effects by activating the AMPK signaling pathway and up-regulating the expression of p-AMPK and PGC-α proteins. Therefore, HFOs-AK can be used as an auxiliary functional dietary molecules to exert its good anti-fatigue activity and be applied to anti-fatigue functional foods.

A Flavonoid Concentrate from Moringa Oleifera Lam. Leaves Extends Exhaustive Swimming Time by Improving Energy Metabolism and Antioxidant Capacity in Mice.

Moringa oleifera Lam. leaves contain various nutrients and bioactive compounds. The present study aimed to assess the anti-fatigue capacity of a flavonoids concentrate purified from M. oleifera Lam. leaves. The total flavonoids in the purified extract were analyzed by ultra-performance liquid chromatography electrospray ionization tandem mass spectrometry (UPLC-MS/MS). The mice were supplemented with purified M. oleifera Lam. leaf flavonoid-rich extract (MLFE) for 14 days. The weight-loaded forced swimming test was used for evaluating exercise endurance. The 90-min non-weight-bearing swimming test was carried out to assess biochemical biomarkers correlated to fatigue and energy metabolism. UPLC-MS/MS analysis identified 83 flavonoids from MLFE. MLFE significantly increased the swimming time by 60%. Serum lactate (9.9 ± 0.9 vs. 8.9 ± 0.7), blood urea nitrogen (BUN) (8.8 ± 0.8 vs. 7.2 ± 0.5), and nonesterified fatty acid (NEFA) (2.4 ± 0.2 vs. 1.7 ± 0.3) were significantly elevated; phosphoenolpyruvate carboxykinase (PEPCK), glucokinase (GCK), and nuclear factor erythroid 2-related factor 2 (Nrf2) mRNA expression were significantly downregulated; and heme oxygenase 1 mRNA expression was significantly upregulated in muscle after swimming. MLFE supplement significantly decreased serum lactate (8.0 ± 1.0 vs. 9.9 ± 0.9), BUN (8.6 ± 0.4 vs. 8.9 ± 0.8), and NEFA (2.3 ± 0.4 vs. 2.4 ± 0.2) and increased the protein and mRNA expression of GCK, PEPCK, and Nrf2. The enhancement of glucose metabolism and antioxidant function by MLFE contributes partly to its anti-fatigue action.

A review of the polysaccharides against fatigue and the underlying mechanism.

Fatigue is a common physiological state that affects normal human activities. Prolonged fatigue induces a variety of diseases and seriously affects human health, so it is imperative to discover nutritional dietary supplements and treatments without side effects, among which natural anti-fatigue polysaccharides have shown great potential. Polysaccharides, a class of biomolecules produced by a variety of organisms such as plants, animals, bacteria and algae, have attracted much attention in recent years due to their anti-fatigue activity and fewer side effects. This review summarizes the classification, dosage and experimental models of polysaccharides with anti-fatigue activity obtained from different natural sources. We also review the fatigue-relieving effects of these polysaccharides through mechanisms such as modulating oxidative damage, regulating energy metabolism and influencing intestinal flora, as well as the effects of molecular weights, monosaccharide compositions, structural features and chemical modifications of the polysaccharides on their anti-fatigue activities to support their potential application value in functional foods and pharmaceuticals. New valuable insights for future research on natural polysaccharides are also presented in the field of natural production of bio-based functional materials, functional foods and therapeutic agents.

Effects of Chlorich®EnergyBoost on Enhancing Physical Performance and Anti-Fatigue Properties in Mice.

Chlorich®EnergyBoost, a water extract obtained from Chlorella sorokiniana, has been proposed to enhance physical performance and provide anti-fatigue effects. This study assessed the impact of Chlorich®EnergyBoost supplementation on physical performance and its anti-fatigue properties. Twenty-four mice were allocated into four groups: (1) the control group receiving only water,;(2) the 1X group (49.2 mg/kg/day); (3) the 2X group (98.4 g/kg/day); and (4) the 5X group (246 g/kg/day). All groups were orally administered the supplements for four consecutive weeks. The evaluation included grip strength, swimming endurance, an exhaustion test, and serum biochemistry analysis. Additionally, the study examined the bioactive peptides through matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS) and conducted bacterial reverse mutation and acute oral toxicity tests for safety assessment. The findings indicated that Chlorich®EnergyBoost supplementation led to a significant reduction in serum lactate levels by 14.08% to 22.54% and blood urea nitrogen levels by 12.23% to 16.76%, an increase in the lactate clearance rate by 0.28 to 0.35, an enhancement of muscle glycogen storage by 1.10 to 1.44-fold, and hepatic glycogen storage by 1.41 to 1.47-fold. These results demonstrated dose-dependent effects. MALDI-TOF analysis revealed the expression of dihydrolipoamide dehydrogenase and superoxide dismutase. Both the bacterial reverse mutation and acute oral toxicity tests showed no adverse effects.

O/W nanoemulsions encapsulated octacosanol: Preparation, characterization and anti-fatigue activity.

Octacosanol has various biological effects such as antioxidant, hypolipidemic and anti-fatigue. However, poor solubility has limited the application of octacosanol in food. The aim of this study was to prepare octacosanol nanoemulsions with better solubility, stability and safety and to investigate in vivo anti-fatigue effect. The food-grade formulation of the octacosanol nanoemulsions consisted of octacosanol, olive oil, Tween 80, glycerol and water with 0.1 %, 1.67 %, 23.75 %, 7.92 % and 66.65 % (w/w), respectively. The nanoemulsions had an average particle size of 12.26 ± 0.76 nm and polydispersity index of 0.164 ± 0.12, and showed good stability under different pH, cold, heat, ionic stress and long-term storage conditions. The results of animal experiments showed that the octacosanol nanoemulsions significantly prolonged the fatigue tolerance time, alleviated the fatigue-related biochemical indicators, and weakened the oxidative stress. Meanwhile, octacosanol nanoemulsions upregulated hepatic glycogen levels. Taken together, these findings suggested that octacosanol nanoemulsions have promising applications as anti-fatigue functional foods.

Pityriasis Rosea-Like Eruption following anti-fatigue traditional herbs: Aconitum carmichaelii Debx and Panax Ginseng suspected.

Traditional herbs have a history of clinical use in anti-fatigue. However, several adverse effects of herbs have been identified. Pityriasis rosea-like eruption (PR-LE) is a rare cutaneous complication of herbs. To the best of our knowledge, there have been few reports of PR-LE following herbs. Here, we described a case of PR-LE that developed 6 days after taking anti-fatigue herbs. After the 17 days of stopping Aconitum carmichaelii Debx and Panax Ginseng, it notably faded. So, when anti-fatigue herbs being authorized for fatigue use, monitoring for potential adverse effects is necessary.

Integration of Metabolomics with Network Pharmacology Deciphers the Anti-Fatigue Activity Mechanisms of the Extract of Mirabilis himalaica Root.

Fatigue, a common symptom in both diseased and healthy individuals, is a biological phenomenon characterized by a sense of extreme physical or mental exhaustion. To explore novel drugs and food sources of anti-fatigue, the hydroalcoholic extract of the root of Mirabilis himalaica (MH extract) is evaluated as anti-fatigue agents in this work, and clarifies that the mechanism of MH intervention in fatigue symptoms, and distribution of the anti-fatigue constituents in the plant of Mirabilis himalaica is examined. The results show that the MH extract have a significantly anti-fatigue effect via the pharmacological experiment and biochemical indicators. The network pharmacology, metabolomics, molecular docking, and pharmacology are integrated to determine that boeravinone A, B, and E are the pharmacoperones of anti-fatigue. Moreover, the compounds of boeravinone are present only in the root and not in the leaf and stem of the Mirabilis himalaica, which validates that root of Mirabilis himalaica is historically and officially utilized medicinal parts.

The Improvement and Related Mechanism of Microecologics on the Sports Performance and Post-Exercise Recovery of Athletes: A Narrative Review.

The diversity and functionality of gut microbiota may play a crucial role in the function of human motor-related systems. In addition to traditional nutritional supplements, there is growing interest in microecologics due to their potential to enhance sports performance and facilitate post-exercise recovery by modulating the gut microecological environment. However, there is a lack of relevant reviews on this topic. This review provides a comprehensive overview of studies investigating the effects of various types of microecologics, such as probiotics, prebiotics, synbiotics, and postbiotics, on enhancing sports performance and facilitating post-exercise recovery by regulating energy metabolism, mitigating oxidative-stress-induced damage, modulating immune responses, and attenuating bone loss. Although further investigations are warranted to elucidate the underlying mechanisms through which microecologics exert their effects. In summary, this study aims to provide scientific evidence for the future development of microecologics in athletics.

Polysaccharides from Artemisia argyi leaves: Environmentally friendly ultrasound-assisted extraction and antifatigue activities.

Artemisia argyi leaf polysaccharide (AALPs) were prepared through ultrasound-assisted extraction (UAE), and their antifatigue activities were evaluated. Extraction was optimized using response surface methodology (RSM), which yielded the following optimal UAE conditions: ultrasonication power of 300 W, extraction temperature of 51 °C, liquid:solid ratio of 20 mL/g, and ultrasonication time of 47 mins. The above optimal conditions resulted in the maximum extraction rate of 10.49 %. Compared with hot water extraction (HWE), UAE supported higher yields and total sugar, uronic acid, and sulfate contents of AALPs. Meanwhile, AALP prepared through UAE (AALP-U) exhibited higher stability due to its smaller particle size and higher absolute value of zeta potential than AALP prepared through HWE (AALP-H). In addition, AALP-U demonstrated stronger antioxidant activity than AALP-H. In forced swimming tests on mice, AALP-U could significantly prolong swimming time with a dose-dependent effect, increase liver and muscle glycogen levels, and improve other biochemical indices, thus showing great potential for application in functional food.

The anti-fatigue and sleep-aiding effects vary significantly among different recipes containing Ganoderma lucidum extracts.

Aims: This study aims to delve into the anti-fatigue and sleep-aiding effects of various formulations containing Ganoderma lucidum extracts. Materials and methods: PGB [incorporating Ganoderma lucidum extract (GE), broken Ganoderma lucidum spore powder (GB) and Paecilomyces hepiali mycelium (PH)] and GBS [composed of GE, GB, and Ganoderma sinense powder (GS)] were chosen as representative recipes for this study. Mice were treated with these recipes or key components of Ganoderma lucidum for 14 consecutive days. Subsequently, a weight-bearing swimming experiment was conducted to assess the mice's exhaustion time and evaluate the anti-fatigue properties of the recipes. Sleep-aiding effects were analyzed by measuring the sleep latency and duration. Furthermore, levels of blood lactic acid, serum urea nitrogen, hepatic glycogen, muscle glycogen, and malondialdehyde (MDA) were measured in the livers and muscles. Key findings: The anti-fatigue abilities of the tested mice were significantly improved after treatment with PGB and their sleep quality improved as well with GBS treatment. PGB treatment for 14 days could significantly prolong the exhaustion time in weight-bearing swimming (from 10.1 ± 0.5 min to 15.2 ± 1.3 min). Meanwhile, glycogen levels in the livers and muscles were significantly increased, while the levels of serum lactic acid, serum urea nitrogen, and MDA in the livers and muscles were significantly decreased. In contrast, mice treated with GBS for 14 days experienced significant improvements in sleep quality, with shortened sleep latency (from 6.8 ± 0.7 min to 4.2 ± 0.4 min), extended sleep duration (from 88.3 ± 1.4 min to 152.5 ± 9.3 min), and decreased muscle MDA levels. These results indicated that Ganoderma lucidum extracts can be used for anti-fatigue and or aid in sleeping, depending on how they are prepared and administered. Significance: This study provides experimental evidence and theoretical basis for the development of Ganoderma lucidum recipes that are specifically designed to help with anti-fatigue and sleep.

Study on Anti-fatigue Effects and Mechanisms of Polysaccharide from Paris polyphylla.

The objectives of this study were to investigate the anti-fatigue effects of Paris polyphylla polysaccharide component 1 (PPPm-1) and explore its mechanisms. A mouse model of exercise-induced fatigue was established by weight-bearing swimming to observe the effects of different concentrations of PPPm-1 on weight-bearing swimming time. The anti-fatigue effect of PPPm-1 was determined by the effects of contraction amplitude, contraction rate, and diastolic rate of the frog gastrocnemius muscle in vivo before and after infiltration with 5 mg/mL PPPm-1. The effects of PPPm-1 on the contents of blood lactate, serum urea nitrogen, hepatic glycogen, muscle glycogen in the exercise fatigue model of mice, and acetylcholine (ACh) content and acetylcholinesterase (AChE) activity at the junction of the frog sciatic nerve-gastrocnemius under normal physiological, and Na+-K+-ATPase and Ca2+-Mg2+-ATPase activities of the frog gastrocnemius were determined by enzyme-linked immunosorbent assay (ELISA), to investigate the anti-fatigue mechanisms of PPPm-1. The results showed that PPPm-1 could significantly prolong the weight-bearing swimming time in mice (P < 0.01), decrease the contents of blood lactate and serum urea nitrogen, increase the contents of the hepatic glycogen and muscle glycogen of mice after exercise fatigue compared with those of the control group, and there was extremely significant difference in most indicators (P < 0.01). The 5 mg/mL of PPPm-1 could significantly promote the contraction amplitude, contraction rate, and relaxation rate of the gastrocnemius muscle in the frogs, and the content of ACh at the junction of the frog sciatic nerve-gastrocnemius (P < 0.01), but it had obvious inhibitory effetc on the activity of AChE at the junction of the frog sciatic nerve-gastrocnemius (P < 0.01). PPPm-1 could increase the Na+-K+-ATPase and Ca2+-Mg2+-ATPase activities of gastrocnemius in the frogs (for Ca2+-Mg2+-ATPase, P < 0.01). The above results suggested that the PPPm-1 had a good anti-fatigue effect, and its main mechanisms were related to improving endurance and glycogen reserve, reducing glycogen consumption, lactate and serum urea nitrogen accumulation, and promoting Ca2+ influx.

Water-soluble biopolymers calcium polymalate derived from fermentation broth of Aureobasidium pullulans markedly alleviates osteoporosis and fatigue.

Osteoporosis is a prevalent condition characterized by bone loss and decreased skeletal strength, resulting in an elevated risk of fractures. Calcium plays a crucial role in preventing and managing osteoporosis. However, traditional calcium supplements have limited bioavailability, poor solubility, and adverse effects. In this study, we isolated a natural soluble biopolymer, calcium polymalate (PMACa), from the fermentation broth of the fungus Aureobasidium pullulans, to investigate its potential as an anti-osteoporosis therapeutic agent. Characterization revealed that linear PMA-Ca chains juxtaposed to form a porous, rod-like state, in the presence of Ca2+. In vivo mouse models demonstrated that PMA-Ca significantly promoted the conversion of serum calcium into bone calcium, and stimulated bone growth and osteogenesis. Additionally, PMA-Ca alleviated exercise fatigue in mice by facilitating the removal of essential metabolites, such as serum lactate (BLA) and blood urea nitrogen (BUN), from their bloodstream. In vitro studies further showed that PMA-Ca strengthened osteoblast cell activity, proliferation, and mineralization. And PMA-Ca upregulated the expression of some genes involved in osteoblast differentiation, indicating a potential correlation between bone formation and PMACa. These findings indicate that soluble PMA-Ca has the potential to be a novel biopolymer-based calcium supplement with sustainable production sourced from the fermentation industry.

A Solid-Liquid Bicontinuous Fiber with Strain-Insensitive Ionic Conduction.

Stretchable ionic conductors are crucial for enabling advanced iontronic devices to operate under diverse deformation conditions. However, when employed as interconnects, existing ionic conductors struggle to maintain stable ionic conduction under strain, hindering high-fidelity signal transmission. Here, it is shown that strain-insensitive ionic conduction can be achieved by creating a solid-liquid bicontinuous microstructure. A bicontinuous fiber from polymerization-induced phase separation, which contains a solid elastomer phase interpenetrated by a liquid ion-conducting phase, is fabricated. The spontaneous partitioning of dissolved salts leads to the formation of a robust self-wrinkled interface, fostering the development of highly tortuous ionic channels. Upon stretch, these meandering ionic channels are straightened, effectively enhancing ionic conductivity to counteract the strain effect. Remarkably, the fiber retains highly stable ionic conduction till fracture, with only 7% resistance increase at 200% strain. This approach presents a promising avenue for designing durable ionic cables capable of signal transmission with minimal strain-induced distortion.

Antioxidant and Anti-Fatigue Effects of a Standardized Botanical Extract Fraction (HemoHIM) in Forced-Exercised Aged Mice.

HemoHIM is a standardized medicinal herbal preparation consisting of extracts of Angelica gigas Nakai, Cnidium officinale Makino, and Paeonia lactiflora Pallas that possesses immune regulatory activities. This study aimed to research the potential antioxidant effects of HemoHIM and its capacity for reducing fatigue in aged mice subjected to forced exercise. After administering HemoHIM 125 (500 mg/kg orally) for 4 weeks in 8-month-old female C57BL/6 mice (4 groups of 10 mice), various parameters were evaluated. The analyses revealed that HemoHIM enhanced swimming time and grip strength. In addition, it significantly reduced serum lactate levels and increased liver glutathione peroxidase (GPx) levels after exercise challenge. The expression levels of antioxidant enzymes and factors, including nuclear factor erythroid 2-related factor-2 (Nrf-2), heme oxygenase 1, superoxide dismutase, GPx, and glutathione reductase, were significantly higher in liver and muscle tissues of mice treated with HemoHIM. These results indicate that HemoHIM might function as an anti-fatigue and antioxidant agent by modulating the Nrf-2 signaling pathway.

Effect of TiC Nanoparticles on a Zn-Al-Cu System for Biodegradable Cardiovascular Stent Applications.

Despite being a weaker metal, zinc has become an increasingly popular candidate for biodegradable implant applications due to its suitable corrosion rate and biocompatibility. Previous studies have experimented with various alloy elements to improve the overall mechanical performance of pure Zn without compromising the corrosion performance and biocompatibility; however, the thermal stability of biodegradable Zn alloys has not been widely studied. In this study, TiC nanoparticles were introduced for the first time to a Zn-Al-Cu system. After hot rolling, TiC nanoparticles were uniformly distributed in the Zn matrix and effectively enabled phase control during solidification. The Zn-Cu phase, which was elongated and sharp in the reference alloy, became globular in the nanocomposite. The strength of the alloy, after introducing TiC nanoparticles, increased by 31% from 259.7 to 340.3 MPa, while its ductility remained high at 49.2% elongation to failure. Fatigue performance also improved greatly by adding TiC nanoparticles, increasing the fatigue limit by 47.6% from 44.7 to 66 MPa. Furthermore, TiC nanoparticles displayed excellent phase control capability during body-temperature aging. Without TiC restriction, Zn-Cu phases evolved into dendritic morphologies, and the Al-rich eutectic grew thicker at grain boundaries. However, both Zn-Cu and Al-rich eutectic phases remained relatively unchanged in shape and size in the nanocomposite. A combination of exceptional tensile properties, improved fatigue performance, better long-term stability with a suitable corrosion rate, and excellent biocompatibility makes this new Zn-Al-Cu-TiC material a promising candidate for biodegradable stents and other biodegradable applications.

Bioguided isolation, identification and bioactivity evaluation of anti-fatigue constituents from Schizophyllum commune.

This study aims to clarify the specific anti-fatigue components of Schizophyllum commune (S.commune) and analyze its potential anti-fatigue mechanism. The main anti-fatigue active ingredient of S.commune was locked in n-butanol extract (SPE-n) by activity evaluation. Twelve compounds were identified by high performance liquid chromatography-electrospray tandem mass spectrometry (LC-ESI-MS/MS). The anti-fatigue effect of morusin is the most predominant among these 12 ingredients. The determination of biochemical indices showed that morusin could increase liver glycogen reserves, improve the activity of antioxidant enzymes in liver, and reduce reactive oxygen species (ROS) content in muscle tissue, thereby reducing myocyte damage. Further studies revealed that morusin could reduce the level of oxidative stress by activating Nrf2/HO-1 pathway, thus alleviating the fatigue of mice caused by exhaustive exercise. The current findings provide a theoretical basis for the development of natural anti-fatigue functional food.

Stretchable, antifatigue, and intelligent nanocellulose hydrogel colorimetric film for real-time visual detection of beef freshness.

The use of biopolymers as matrices and anthocyanins as pH-sensing indicators has generated increasing interest in freshness detection. Nevertheless, the weak mechanical properties and color stability of biopolymer-based smart packaging systems restrict their practicality. In this study, a nanocellulose hydrogel colorimetric film with enhanced stretchability, antifatigue properties, and color stability was prepared using soy hull nanocellulose (SHNC), polyvinyl alcohol (PVA), sodium alginate (SA), and anthocyanin (Anth) as raw materials. This hydrogel colorimetric film was used to detect beef freshness. The structure and properties (e.g., mechanical, thermal stability and hydrophobicity) of these hydrogel colorimetric films were characterized using different techniques. Fourier-transform infrared spectroscopy revealed the presence of hydrogen and ester bonds in the hydrogel colorimetric films, whereas scanning electron microscopy revealed the fish scale-like and honeycomb network structure of the hydrogel colorimetric films. Mechanical testing demonstrated that the SHNC/PVA/SA/Anth-2 hydrogel colorimetric film exhibited excellent tensile properties (elongation = 261 %), viscoelasticity (storage modulus of 11.25 kPa), and mechanical strength (tensile strength = 154 kPa), and the hydrogel colorimetric film exhibited excellent mechanical properties after repeated tensile tests. Moreover, the hydrogel colorimetric film had high transparency, excellent anti-UV linearity, thermal stability and hydrophobicity, and had displayed visually discernible color response to pH buffer solution and volatile NH3 by naked eyes, which was highly correlated with the TVB-N and pH values. Notably, the release of anthocyanin in distilled water decreased from 81.23 % to 19.87 %. The designed SHNC/PVA/SA/Anth hydrogel colorimetric films exhibited potential application as smart packaging film or gas-sensing labels in monitoring the freshness of meat products.

Effect of HY7602 Fermented Deer Antler on Physical Fatigue and Antioxidant Activity in Mice.

Lactobacillus curvatus HY7602 fermented antler (FA) ameliorates sarcopenia and improves exercise performance by increasing muscle mass, muscle fiber regeneration, and mitochondrial biogenesis; however, its anti-fatigue and antioxidant effects have not been studied. Therefore, this study aimed to investigate the anti-fatigue and antioxidant effects and mechanisms of FA. C2C12 and HepG2 cells were stimulated with 1 mM of hydrogen peroxide (H2O2) to induce oxidative stress, followed by treatment with FA. Additionally, 44-week-old C57BL/6J mice were orally administered FA for 4 weeks. FA treatment (5-100 µg/mL) significantly attenuated H2O2-induced cytotoxicity and reactive oxygen species (ROS) production in both cell lines in a dose-dependent manner. In vivo experiments showed that FA treatment significantly increased the mobility time of mice in the forced swimming test and significantly downregulated the serum levels of alanine aminotransferase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), creatine kinase (CK), and lactate. Notably, FA treatment significantly upregulated the activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione/oxidized glutathione ratio (GSH/GSSG) and increased the mRNA expression of antioxidant genes (SOD1, SOD2, CAT, GPx1, GPx2, and GSR) in the liver. Conclusively, FA is a potentially useful functional food ingredient for improving fatigue through its antioxidant effects.

Camellia oil exhibits anti-fatigue property by modulating antioxidant capacity, muscle fiber, and gut microbial composition in mice.

Camellia seed oil (CO) has high nutritional value and multiple bioactivities. However, the specific anti-fatigue characteristics and the implied mechanism of CO have not yet been fully elucidated. Throughout this investigation, male C57BL/6J mice, aged 8 weeks, underwent exhaustive exercise with or without CO pretreatment (2, 4, and 6 mL/kg BW) for 28 days. CO could extend the rota-rod and running time, reduce blood urea nitrogen levels and serum lactic acid, and increase muscle and hepatic glycogen, adenosine triphosphate, and anti-oxidative indicators. Additionally, CO could upregulate the mRNA and Nrf2 protein expression levels, as well as enhance the levels of its downstream antioxidant enzymes and induce the myofiber-type transformation from fast to slow and attenuate the gut mechanical barrier. Moreover, CO could ameliorate gut dysbiosis by reducing Firmicutes to Bacteroidetes ratio at the phylum level, increasing the percentage of Alistipes, Alloprevotella, Lactobacillus, and Muribaculaceae, and decreasing the proportion of Dubosiella at the genus level. In addition, specific bacterial taxa, which were altered by CO, showed a significant correlation with partial fatigue-related parameters. These findings suggest that CO may alleviate fatigue by regulating antioxidant capacity, muscle fiber transformation, gut mechanical barrier, and gut microbial composition in mice. PRACTICAL APPLICATION: Our study revealed that camellia seed oil (CO) could ameliorate exercise-induced fatigue in mice by modulating antioxidant capacity, muscle fiber, and gut microbial composition in mice. Our results promote the application of CO as an anti-fatigue functional food that targets oxidative stress, myofiber-type transformation, and microbial community.