RESUMEN
In contemporary applications, smart surfaces capable of altering their properties in response to external stimuli have garnered significant attention. Nonetheless, the efficient creation of smart surfaces exhibiting robust and rapid responsiveness and meticulous controllability on a large scale remains a challenge. This paper introduces an innovative approach to fabricate smart surfaces with strong pH-responsiveness, combining femtosecond laser direct writing (LDW) processing technology with stimulus-responsive polymer grafting. The proposed model involves the grafting of poly(2-diethylaminoethyl methacrylate) (PDEAEMA) onto rough and patterned Au/polystyrene (PS) bilayer surfaces through Au-SH bonding. The incorporation of LDW processing technology extends the choice of microstructures and roughness achievable on material surfaces, while PDEAEMA imparts pH responsiveness. Our findings revealed that the difference in contact angle between acidic and basic droplets on the rough PDEAEMA-g-Au surface (â¼118°) greatly surpasses that on the flat PDEAEMA-g-Au surface (â¼72°). Next, by leveraging the precision control over surface microstructures enabled by the LDW processing technique, this difference was further augmented to â¼127° on the optimized patterned PDEAEMA-g-Au surface. Further, we created two distinct combined smart surfaces with varying wettability profiles on which the hydrophilic-hydrophobic boundaries exhibit reliable asymmetric wettability for acidic and basic droplets. Additionally, we prepared a separator, realizing a better visual distinction between acid and base and collecting them separately. Given the effective abilities found in this study, we postulate that our smart surfaces hold substantial potential across diverse applications, encompassing microfluidic devices, intelligent sensors, and biomedicine.
RESUMEN
A highly oriented poly(l-lactic acid) (PLLA), with a blood vessel-like biomimetic structure, was fabricated using solid-phase hot drawing technology and homo-epitaxial crystallization to improve the mechanical properties and biocompatibility of PLLA. Long chain branched PLLA (LCB-PLLA) was prepared through a two-step ring-opening reaction, and a consequent draw as high as 1000 % was achieved during the hot drawing. The modulus and tensile strength were found to have increased through the formation of oriented shish-kebab like crystals along the drawing direction during processing. Furthermore, PLLA nano-lamellae were formed on the surface of the oriented plates via the introduction of homo-epitaxial crystallization. The high degree of orientation and epitaxial crystallization substantially enhanced the biocompatibility of the PLLA by prolonging clotting time, decreasing the rate of hemolysis, and increasing the cell growth and reproduction of the osteoblasts.
Asunto(s)
Materiales Biocompatibles , Biónica , Materiales Biocompatibles/química , Poliésteres/química , Resistencia a la TracciónRESUMEN
Hollow carbon-coated In2O3 (C#In2O3) nanofibers were prepared using an efficiently combined approach of electrospinning, high-temperature calcination, and hydrothermal process. The polyaniline (PANI)/hollow C#In2O3 nanofiber composites were synthesized used hollow C#In2O3 nanofibers worked as a core through the in situ chemical oxidative polymerization. The morphology and crystalline structure of the PANI/hollow C#In2O3 nanofiber composite were identified using wide-angle X-ray diffraction and transmission electron microscopy. The gas-sensing performances of the fabricated PANI/hollow C#In2O3 nanofiber composite sensor were estimated at room temperature, and the response value of the composite sensor with an exposure of 1 ppm NH3 was 18.2, which was about 5.74 times larger than that of the pure PANI sensor. The PANI/hollow C#In2O3 nanofiber composite sensor was demonstrated to be highly sensitive to the detection of NH3 in the concentration range of 0.6~2.0 ppm, which is critical for kidney or hepatic disease detection from the human breath. This composite sensor also displayed superior repeatability and selectivity at room temperature with exposures of 1.0 and 2.0 ppm NH3. Because of the outstanding repeatability and selectivity to the detection of NH3 at 1.0 and 2.0 ppm confirmed in this investigation, the PANI/hollow C#In2O3 nanofiber composite sensor will be considered as a favorable gas-sensing material for kidney or hepatic disease detection from human breath.
Asunto(s)
Amoníaco , Nanofibras , Compuestos de Anilina , Carbono , Humanos , Indio , Nanofibras/química , TemperaturaRESUMEN
Mixed-halide perovskites can undergo a photoinduced phase segregation. Even though many reports have claimed that such a phase segregation process is reversible, what happens after phase segregation and its impact on the performance of perovskite-based devices are still open questions. Here, the phase transformation of MAPb(I1- x Brx )3 after phase segregation and probe an irreversible phase reconstruction of MAPbBr3 is investigated. The photoluminescence imaging microscopy technique is introduced to in situ record the whole process. It is proposed that the type-I band alignment of segregated I-rich and Br-rich domains can enhance the emission of the I-rich domains by suppressing the nonradiative recombination channels. At the same time, the charge injection from Br-rich to I-rich domains drives the expulsion of iodide from the lattice, and thus triggers the reconstruction of MAPbBr3 . The work highlights the significance of ion movements in mixed-halide perovskites and provides new perspectives to understand the property evolution.
RESUMEN
Highly crystalline perovskite films with large grains and few grain boundaries are conducive for efficient and stable perovskite solar cells. Current methods for preparing perovskite films are mostly based on a fast crystallization process, with rapid nucleation and insufficient growth. In this study, MAPbI3 perovskite with inhibited nucleation and promoted growth in the TiO2/ZrO2/carbon triple mesoscopic scaffold was crystallized by modulating the precursor and the crystallization process. N-methylformamide showed high solubility for both methylammonium iodide and PbI2 and hampered the formation of large colloids in the MAPbI3 precursor solution. Furthermore, methylammonium chloride was added to reduce large colloids, which are a possible source of nucleation sites. During the crystallization of MAPbI3, the solvent was removed at a slow controlled speed, to avoid rapid nucleation and provide sufficient time for crystal growth. As a result, highly oriented MAPbI3 crystals with suppressed non-radiative recombination and promoted charge transport were obtained in the triple mesoscopic layer with disordered pores. The corresponding hole-conductor-free, printable mesoscopic perovskite solar cells exhibited a highest power conversion efficiency of 18.82%. The device also exhibited promising long-term operational stability of 1000 h under continuous illumination at maximum power point at 55 ± 5 °C and damp-heat stability of 1340 h aging at 85 °C as well as 85% relative humidity.
RESUMEN
Hollow indium trioxide (In2O3) nanofibers fabricated via an effectively combined method of electrospinning and high-temperature calcination were coated with nitrogen-doped graphene quantum dots (N-GQDs) prepared by a hydrothermal process through electrostatic interaction. The N-GQD-coated hollow In2O3 nanofibers served as a core for the synthesis of polyaniline (PANI)/N-GQD/hollow In2O3 nanofiber ternary composites using in situ chemical oxidative polymerization. The chemical structure and morphology of the fabricated ternary composites were characterized using Fourier transform infrared, field-emission scanning electron microscopy, and transmission electron microscopy. The gas-sensing performances of the ternary composites were estimated by a homemade dynamic test system which was supplied with a real-time resistance acquisition platform at room temperature. The response value of the PANI/N-GQD/hollow In2O3 nanofiber sensor with a loading of 20 wt% N-GQD-coated hollow In2O3 nanofiber and an exposure of 1 ppm NH3 was 15.2, which was approximately more than 4.4 times higher than that of the PANI sensor. This ternary composite sensor was proved to be very sensitive in the detection of NH3 at a range of concentration between 0.6 ppm and 2.0 ppm at room temperature, which is crucial in the detection of hepatic or kidney disease in human breath. The PANI/N-GQD/hollow In2O3 nanofiber sensor also revealed higher selectivity and repeatability when exposed to 1.0 and 2.0 ppm NH3 at room temperature. Because of the excellent selectivity and repeatability in the detection of 1.0 and 2.0 ppm NH3 at room temperature achieved in this study, it is considered that the PANI/N-GQD/hollow In2O3 nanofiber composite sensor will be a favored gas-sensing material applied on human breath for the detection of hepatic or kidney disease.
RESUMEN
The anion exchange between MAPbX3 (X = I- or Br-) and MAX salts in a solution environment is investigated. We find that I- can enter MAPbBr3 single crystals (SC) in millimeter scale, while Br- can only penetrate the surface of MAPbI3 SC in a micrometer scale. Due to the lattice variation, the reaction is partially reversible.
RESUMEN
The crystallization mechanism of the perovskite crystals inside the mesopores of printable mesoscopic perovskite solar cells is demonstrated by in situ grazing-incidence X-ray diffraction. Ionic liquids can universally tune the crystallization process of different perovksites in the mesopores regradless of the precursor solvents, resulting in enhanced efficiency.
RESUMEN
Thin-film composite (TFC) polyamide membranes formed through interfacial polymerization can function more efficiently by tuning the chemical structure of participating monomers. Accordingly, three kinds of diamine monomers were considered to take part in interfacial polymerization. Each diamine was reacted with trimesoyl chloride (TMC) to manufacture TFC polyamide nanofiltration (NF)-like forward osmosis (FO) membranes. The diamines differed in chemical structure; the functional group present between the terminal amines was classified as follows: aliphatic group of 1,3-diaminopropane (DAPE); cyclohexane in 1,3-cyclohexanediamine (CHDA); and aromatic or benzene ring in m-phenylenediamine (MPD). For FO tests, deionized water and 1 M aqueous sodium sulfate solution were used as feed and draw solution, respectively. Interfacial polymerization conditions were also varied: concentrations of water and oil phases, time of contact between the water-phase solution and the membrane substrate, and polymerization reaction time. The resultant membranes were characterized using attenuated total reflectance-Fourier transform infrared spectroscopy, field emission scanning electron microscopy, atomic force microscopy, and surface contact angle measurement to identify the chemical structure, morphology, roughness, and hydrophilicity of the polyamide layer, respectively. The results of FO experiments revealed that among the three diamine monomers, CHDA turned out to be the most effective, as it led to the production of TFC NF-like FO membrane with optimal performance. Then, the following optimum conditions were established for the CHDA-based membrane: contact between 2.5 wt.% aqueous CHDA solution and polysulfone (PSf) substrate for 2 min, and polymerization reaction between 1 wt.% TMC solution and 2.5 wt.% CHDA solution for 30 s. The composite CHDA-TMC/PSf membrane delivered a water flux (Jw) of 18.24 ± 1.33 LMH and a reverse salt flux (Js) of 5.75 ± 1.12 gMH; therefore, Js/Jw was evaluated to be 0.32 ± 0.07 (g/L).
RESUMEN
Construction of segregated structures in polymer composites is an efficient way to improve the electrical conductivity and reduce the percolation threshold by confining conductive fillers into the interstitial areas between polymer domains. Yet, it remains a great challenge to engineer segregated structures into thermosets as the cross-linked structure prohibits the "sintering" of polymer domains into a coherent material. Thus far, the state of art approaches to create segregated network in cross-linked polymers involve tedious procedures and are limited to latex mixing technology. Here, inspired by solid state plasticity of vitrimers, we present a simple method to create segregated structures in covalently cross-linked networks by compression molding of conductive filler-coated vitrimer granules. Specifically, dynamic boronic ester-cross-linked styrene-butadiene rubber vitrimers was ground into granules and then mechanically mixed with carbon nanotubes (CNTs) to coat CNTs onto vitrimer granules, followed by hot-press molding. During the molding process, the transesterifications of boronic esters enable cross-linked granules to adhere together through molecular bonding, and the high viscosity of granules forces CNTs to selectively localize at their boundary region. As a result, coherently segregated composites with an ultralow percolation threshold, good flexibility, and healing capability are obtained. With this example, we envisage that this work provides a conceptual method to create segregated structures in cross-linked polymers.
Asunto(s)
Nanotubos de Carbono , Conductividad Eléctrica , Látex , Nanotubos de Carbono/química , Polímeros/químicaRESUMEN
Environmental endocrine disruptors 4-nonylphenol (NP) and 4-tert-octylphenol (OP) may cast huge harm to human health. We used a rat model to observe the influence of NP or/and OP exposure on anxiety-related behaviors and the underlying mechanisms. Eighty male Sprague-Dawley (SD) rats were randomly divided into 10 groups: control group (corn oil), NP groups [30, 90, 270 mg/kg], OP groups [40, 120, 360 mg/kg] and NO groups [(mixed with the corresponding NP, OP alone exposed low, medium and high dose according to the natural environment exists NP:OP = 4:1]. The rats were orally administered every other day for 30 days. The neurobehaviors of rats were evaluated by open-field test (OFT) and elevated plus-maze test (EPM), and the concentrations of 5-HT, monoamine oxidase (MAOA), serotonin transporter (SERT), vesicular monoamine transporter 2 (VAMT2), 5-hydroxytryptamine 1A (5-HT1A), 5-hydroxytryptamine 2A (5-HT2A)ï¼and 5-hydroxytryptamine 2C (5-HT2C) in the rat prefrontal cortex were analyzed by ELISA. OFT and EPM tests showed that NP or/and OP exposure induced anxiety-related behaviors in rats. 5-HT levels were significantly increased compared with the control group. The levels of MAOA, SERT, VAMT2, 5-HT1A, 5-HT2A, and 5-HT2C in the prefrontal cortex reduced in different degrees by high-doses NP or/and OP exposure. In summary, NP or/and OP exposure might cause anxiety-related behaviors in rats through regulating neurotransmitter 5-HT levels by altering the expression of 5-HT decomposition enzyme MAOA, transporters SERT and VMAT2, and 5-HT receptors 5-HT1A, 5-HT2A, and 5-HT2C.
Asunto(s)
Fenoles/toxicidad , Corteza Prefrontal/metabolismo , Receptores de Serotonina/metabolismo , Serotonina/metabolismo , Animales , Ansiedad , Conducta Animal , Masculino , Aprendizaje por Laberinto , Monoaminooxidasa/metabolismo , Ratas , Ratas Sprague-Dawley , Proteínas de Transporte de Serotonina en la Membrana Plasmática/metabolismoRESUMEN
Studies have shown that diet and nutrition play significant roles in the prevention of depression and its clinical treatment. The present review aims to provide a clear understanding of the associations between diet patterns, specific foods, nutrients such as antioxidants, and depression. As a result, balanced dietary patterns such as the Mediterranean diet and certain foods such as fish, fresh vegetables, and fruits have been associated with a lower risk of depression or depressive symptoms, while high-fat Western diets and sugar-sweetened beverages have been associated with higher risk of depression or depressive symptoms. Dietary antioxidants such as green tea polyphenols or isoflavonoid intake have been negatively associated with depression or depressive symptoms. It is concluded that diet patterns, specific foods, and antioxidants play important roles in the prevention and clinical treatment of depression.
RESUMEN
PURPOSE: Nonylphenol (NP) is one widely distributed representative of environmental estrogens that disturb reproductive activities, bone metabolism and brain function through interfering diverse signal pathways leading to hormone metabolic dysfunctions, immunologic derangement, and tumorigenesis. Few of previous studies have observed the subacute toxicity on rodents, and little has been focused on the mechanism underneath the toxicities observed. METHODS: The 32 male Sprague-Dawley (SD) rats were randomly divided into four groups, the negative control group (corn oil) NP low, medium and high dose groups [30, 90, 270 mg/(kg·d)]. SD rats administrated with different dosage of NP every other day for 28d. Elisa and RT-PCR was employed to observe estrogen metabolism markers or mRNA expressions. RESULTS: In serum, NP exposure caused testosterone (T) (pâ¯<â¯0.001), progesterone (PROG) (pâ¯<â¯0.05) and estrone (E1) (pâ¯<â¯0.05) increased. In testicle, NP exposure caused T (pâ¯<â¯0.001), PROG (pâ¯<â¯0.05), E1 (pâ¯<â¯0.05), 17ß-estradiol (E2) (pâ¯<â¯0.05) and ERα mRNA (pâ¯<â¯0.01) increased, while P450 aromatizing enzyme (pâ¯<â¯0.001) decreased in NPL and ERß mRNA (pâ¯<â¯0.001) decreased in NPM and NPH. In liver, NP exposure caused 17ß-HSD2 mRNA (pâ¯<â¯0.01) increased, while P450 aromatizing enzyme decreased (pâ¯<â¯0.05). CONCLUSION: NP exposure exhibited general and estrogenic toxicity in rats through disturbing estrogen secretion network and estrogen receptor expression network, inducing abnormal metabolism of estrogen, whether in serum, liver and testicle.
Asunto(s)
Disruptores Endocrinos/toxicidad , Estrógenos/metabolismo , Hígado/metabolismo , Fenoles/toxicidad , Testículo/metabolismo , Animales , Sistema Enzimático del Citocromo P-450/metabolismo , Estradiol/metabolismo , Receptor alfa de Estrógeno/metabolismo , Receptor beta de Estrógeno/metabolismo , Estrona/metabolismo , Femenino , Masculino , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores de Estrógenos/metabolismo , Testosterona/metabolismo , Pruebas de ToxicidadRESUMEN
This study evaluated toxic effects of nonylphenol (NP) and octylphenol (OP) on central 5-hydroxytryptamine (5-HT) system and related learning and memory in the rats. Male Sprague-Dawley rats were exposed to NP (30, 90, or 270â¯mg/kg), OP (40, 120, or 360â¯mg/kg), or a mixture of NP and OP [(mixed with the corresponding NP, OP alone exposed low, medium and high dose according to the natural environment exists NP:OP = 4:1; NOL (24â¯mg/kg NP+8â¯mg/kg OP), NOM (72â¯mg/kg NP+24â¯mg/kg OP), NOH (216â¯mg/kg NP+72â¯mg/kg OP)] by gavage every other day for 30 d. Learning and memory were assessed using a passive-avoidance test. Levels of estrogen receptor ß (ERß), 5-HT, tryptophan hydroxylase 2 (TPH2), monoamine oxidase (MAOA) enzyme, serotonin transporter (SERT), the vesicular monoamine transporter 2 (VMAT2), 5-hydroxytryptamine 1â¯A (5-HT1A), 5-hydroxytryptamine 3â¯A (5-HT3A), 5-hydroxytryptamine 3B (5-HT3B), 5-hydroxytryptamine 4â¯A (5-HT4A) and 5-hydroxytryptamine 6â¯A (5-HT6A) were measured using ELISA kits. Levels of ERß, MAOA, SERT, VMAT2, 5-HT1A, 5-HT3A, 5-HT3B, 5-HT4A and 5-HT6A in rat hippocampal reduced by a high dose of NP and/or OP. Levels of TPH2 in rat midbrain and 5-HT in rat hippocampal increased by a high dose of NP and/or OP. In addition, latency was significantly shorter and errors were significantly greater in the high dose NP and NP+OP (NO) groups. Taken together, these results suggest that NP and/or OP may affect learning and memory in rats by inhibiting levels of ERß, which could then lead to decreases in levels of 5-HT1A, 5-HT3A, 5-HT3B, 5-HT4A, and 5-HT6A in the rat hippocampus. These findings suggested that separate and combined exposure to NP and OP could produce toxic effects on central 5-HT system and related learning and memory in the rats.
Asunto(s)
Aprendizaje/efectos de los fármacos , Memoria/efectos de los fármacos , Fenoles/toxicidad , Serotonina/toxicidad , Animales , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Masculino , Monoaminooxidasa/metabolismo , Proteínas de Unión al ARN/metabolismo , Ratas , Ratas Sprague-Dawley , Triptófano Hidroxilasa/metabolismo , Proteínas de Transporte Vesicular de Monoaminas/metabolismoRESUMEN
Nonylphenol (NP) is an endocrine-disrupting chemical (EDC) that can lead to thyroid disruption. We explored NP-induced toxicity in the rat thyroid and evaluated the mitigating effects of mulberry crude extract (MCE) on NP toxicity. First, we aimed to evaluate NP-induced thyroid disruption by dosing Sprague-Dawley (SD) rats with NP (0, 30, 90, or 270â¯mg/kg body weight) daily for 28â¯days. Second, we aimed to determine whether MCE had a detoxifying effect on NP-induced thyroid disruption by dosing SD rats with NP (270â¯mg/kg body weight) or/and MCE (30, 60, or 120â¯mg/kg body weight) daily for 28â¯days. We found that NP significantly inhibited free triiodothyronin (FT3) and free thyroxine (FT4) activity in rat serum (Pâ¯<â¯0.05), but MCE intervention significantly increased FT3 and FT4 serum levels (Pâ¯<â¯0.05). It is possible that changes in hormonal composition might trigger the TRH-TSH-TH automatic feedback loop. The activity of the three iodothyronine deiodinases increased significantly after NP-dosing (Pâ¯<â¯0.05), but only deiodinase3 (D3) was downregulated after MCE treatment (Pâ¯<â¯0.05). Therefore, MCE might be an effective NP-detoxification agent against thyroid disruption because it regulates D3 activity.
Asunto(s)
Yoduro Peroxidasa/metabolismo , Morus/química , Glándula Tiroides/efectos de los fármacos , Hormonas Tiroideas/sangre , Animales , Masculino , Ratas , Ratas Sprague-DawleyRESUMEN
The fascinating properties of carbon nanotubes (CNTs) make them highly promising in fabricating polymer composites. Yet, the property enhancements of polymer/CNTs composites remain far behind the theoretical predictions. A critical issue to resolve this dilemma is to align CNTs in polymer matrices. Thus far, the state of art approaches to create CNT alignment either require complicated preparation processes and specific apparatuses, or is limited to thermoplastic polymers. Here, inspired by the network rearrangement ability of vitrimer in the solid state, we bring forth a facile methodology to align CNT in covalently cross-linked polymers by uniaxially stretching dynamic. Specifically, dynamic boronic ester bond-cross-linked epoxidized natural rubber/CNTs vitrimer composites with randomly dispersed CNTs are prepared, which are able to rearrange the network topologies and release stress at elevated temperatures through boronic ester transesterifications. The alignment of CNTs is performed by the uniaxial stretching of the composites and subsequent cross-link reshuffling at elevated temperatures, which results in anisotropic composites with remarkably enhanced mechanical properties and reduced electrical conductivity along the stretching direction. Furthermore, the mechanical properties of the composites can be readily adjusted by changing the applied strain, relaxation time and temperature due to the modulated CNT alignment degree. With this example, we envisage that this work offers a conceptual and facile approach to align anisotropic fillers in covalently cross-linked polymers.
RESUMEN
Adjusting dietary fat intake is reported to affect mitochondrial biogenesis and fatty acid oxidation (FAO), and thus may enhance exercise capacity. However, a high-fat diet where carbohydrate intake is not limited enough also makes it difficult for athletes to maintain weight, and may fail to force the body to utilize fat. As such, a low-carbohydrate, high-fat, ketogenic diet (KD) may be viable. We have previously reported that an eight-week KD enhances exercise capacity, and suggested the mechanism to be enhanced lipolysis and ketolysis. In the present study, we investigated how an eight-week KD alters mRNA expression during fatty acid mobilization, FAO and ketolysis. We found that an eight-week KD may remodel the lipid metabolism profile, thus contributing to influence exercise capacity. We also found that ketolysis, lipolysis and FAO adaptations may contribute to enhanced exhaustive exercise performance. Along with enhanced FAO capacity during exhaustive exercise, a KD may also alter IL-6 synthesis and secretion profile, thus contribute to fatty acid mobilization, ketolysis, lipolysis and preventing muscle damage. Both the lipid metabolism response and IL-6 secretion appeared to be muscle fiber specific. Taken together, the previous and present results reveal that an eight-week KD may enhance exercise performance by up-regulating ketolysis and FAO ability. Therefore, a KD may have the potential to prevent muscle damage by altering IL-6 secretion profile, indicating that a KD may be a promising dietary approach in endurance athletes, sports, and for injury prevention.
Asunto(s)
Dieta Cetogénica , Interleucina-6/sangre , Metabolismo de los Lípidos/genética , Condicionamiento Físico Animal , Ácido 3-Hidroxibutírico/sangre , Adiposidad , Animales , Ácidos Grasos no Esterificados/sangre , Regulación de la Expresión Génica , Glucógeno/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Músculo Esquelético/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismoRESUMEN
A low-carbohydrate, high-fat ketogenic diet (KD) is a nutritional approach ensuring that the body utilizes lipids. In our previous study, we found that an eight-week ketogenic high-fat, low-carbohydrate diet increased the capacity of endurance exercise in mice without aggravated muscle injury, despite the decrease of absolute muscle volume. The potential mechanism is most possibly to be enhanced capacity to mobilize and utilize fat. In the present study, we investigated whether a ketogenic diet influences post-exercise recovery by measuring blood biomarkers, muscle and liver oxidative state as well as fatigue recovery 24 h post exercise by employing an open-field locomotion test. Several biochemistry markers indicating exercise-induced injury after exhaustive exercise were improved by KD, followed by a 24-h rest with free feed access, including lactate. No aggravated hepatic oxidative damage was observed, whereas muscular oxidative stress was increased by KD. Accelerated recovery induced by exhaustive exercise was also observed from blood biomarkers of injury. For fatigue recovery, lactate concentration, a marker often employed as exhaustion index was lowered by KD, whereas an open field test showed that KD application contributed to increased locomotion after exhaustive exercise, followed by a 24-h rest. These results suggest that KD has the potential to be used as a fatigue-preventing and/or recovery-promoting diet approach in endurance athletes.
Asunto(s)
Dieta Alta en Grasa , Dieta Cetogénica , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Tolerancia al Ejercicio , Contracción Muscular , Fatiga Muscular , Músculo Esquelético/fisiología , Estrés Oxidativo , Animales , Antioxidantes/metabolismo , Biomarcadores/sangre , Carbohidratos de la Dieta/metabolismo , Grasas de la Dieta/efectos adversos , Ácido Láctico/sangre , Masculino , Ratones Endogámicos C57BL , Músculo Esquelético/metabolismo , Recuperación de la Función , Factores de TiempoRESUMEN
Current fueling tactics for endurance exercise encourage athletes to ingest a high carbohydrate diet. However, athletes are not generally encouraged to use fat, the largest energy reserve in the human body. A low carbohydrate, high fat ketogenic diet (KD) is a nutritional approach ensuring that the body utilizes lipids. Although KD has been associated with weight-loss, enhanced fat utilization in muscle and other beneficial effects, there is currently no clear proof whether it could lead to performance advantage. To evaluate the effects of KD on endurance exercise capacity, we studied the performance of mice subjected to a running model after consuming KD for eight weeks. Weight dropped dramatically in KD-feeding mice, even though they ate more calories. KD-feeding mice showed enhanced running time without aggravated muscle injury. Blood biochemistry and correlation analysis indicated the potential mechanism is likely to be a keto-adaptation enhanced capacity to transport and metabolize fat. KD also showed a potential preventive effect on organ injury caused by acute exercise, although KD failed to exert protection from muscle injury. Ultimately, KD may contribute to prolonged exercise capacity.