Search

This study aimed to investigate the effects of dietary Eucommia ulmoides leaf extract (ELE) on meat quality, antioxidant capacity, and lipid metabolism in finishing pigs. A total of 240 "Duroc × Landrace × Yorkshire" crossbred pigs with an initial weight of 74.70 ± 0.77 kg were randomly assigned to two groups: control group and 0.2% ELE group, with each group containing 10 replicates of 12 pigs per pen (half barrows and half gilts). The data showed dietary 0.2% ELE supplementation did not affect growth performance but tended to reduce the backfat thickness of the finishing pigs (p = 0.07). ELE diets increased pH value (p < 0.05) and meat color score (p = 0.01) and decreased 45 min L* value (p < 0.05), 24 h L* value (p = 0.01), pressurization loss (p = 0.01), and 24 h drip loss (p < 0.05) in longissimus dorsi (LD) muscle, accompanied by an increased (p < 0.05) proportion of monounsaturated fatty acids (MUFA) and decreased polyunsaturated fatty acids (PUFA) (p = 0.06) and n-6/n-3 PUFA ratio (p = 0.05) compared to controls. In addition, ELE supplementation increased inosine monophosphate (IMP) (p = 0.01), sweet amino acids (AAs) (p < 0.05), and total free AA content (p = 0.05) in LD. Meanwhile, increased activity of glutathione peroxidase (p < 0.05) and superoxide dismutase (p < 0.01) in both serum and LD muscle and decreased malondialdehyde content (p < 0.01) in LD muscle were detected with ELE treatment. Moreover, pigs fed ELE had a higher total protein (p < 0.01), albumin (p < 0.05), and high-density lipoprotein cholesterol (p < 0.05) and a lower total cholesterol (p < 0.01) and triacylglycerols (p = 0.06) in serum. Consistently, significant effects of dietary ELE were observed on the relative mRNA expression of lipid metabolism in the backfat and the LD muscle, respectively. ELE attenuated lipogenic processes in backfat, decreasing the relative expression of acetyl-CoA carboxylase and upregulating the relative expression of adipose triacyl glyceride lipase, carnitine palmitoyl transferase 1B, and fatty acid-binding protein 4 (p < 0.05). ELE also decreased the relative expression of CCAAT/enhancer-binding protein α (p < 0.05), fatty acid translocase (p < 0.05), carnitine palmitoyl transferase 1B (p < 0.01), and adipose triacyl glyceride lipase (p < 0.05) in LD muscle (p < 0.05). More specifically, lipogenesis appeared to be inhibited in both LD muscle and backfat, with the difference being that lipolysis was enhanced in backfat and inhibited in LD muscle. In conclusion, dietary ELE supplementation can potentially enhance carcass traits, sensory quality, and nutritional value of pork without negatively affecting intramuscular fat content. The underlying mechanism for these positive effects may be linked to the alterations in lipid metabolism and increased antioxidant capacity induced by ELE. [ABSTRACT FROM AUTHOR]

This study aimed to explore the effects of the incremental injection of lipopolysaccharide (LPS) on liver histopathology, inflammation, oxidative status, and mitochondrial function in piglets. Forty healthy Duroc × Landrace × Yorkshire castrated boars (21 ± 2 days old, weight 6.84 ± 0.11 kg) were randomly assigned to five groups (n = 8) and then slaughtered on days 0 (group 0, without LPS injection), 1 (group 1), 5 (group 5), 9 (group 9), and 15 (group 15) of LPS injection, respectively. The results showed that, compared to the piglets without LPS injection, LPS injection caused liver injury in the early phase, as manifested by the increased activities of serum liver injury-related parameters (aspartate amino transferase, alanine aminotransferase, alkaline phosphatase, cholinesterase, and total bile acid) on day 1, and impaired liver morphology (disordered hepatic cell cord arrangement, dissolved and vacuolized hepatocytes, karyopycnosis, and inflammatory cell infiltration and congestion) on days 1 and 5. Meanwhile, LPS injection caused liver inflammation, oxidative stress, and mitochondrial dysfunction on days 1 and 5, as reflected by the upregulated mRNA expression of TNF-α, IL-6, IL-1β, TLR4, MyD88, and NF-κB; increased MPO and MDA content; and impaired mitochondrial morphology. However, these parameters were ameliorated in the later phase (days 9~15). Taken together, our data indicate that the incremental injection of the LPS-induced liver injury of piglets could be self-repaired. [ABSTRACT FROM AUTHOR]

Iron is a trace element necessary for cell growth, development, and cellular homeostasis, but insufficient or excessive level of iron is toxic. Intracellularly, sufficient amounts of iron are required for mitochondria (the center of iron utilization) to maintain their normal physiologic function. Iron deficiency impairs mitochondrial metabolism and respiratory activity, while mitochondrial iron overload promotes ROS production during mitochondrial electron transport, thus promoting potential disease development. This review provides an overview of iron homeostasis, mitochondrial iron metabolism, and how mitochondrial iron imbalances-induced mitochondrial dysfunction contribute to diseases. [ABSTRACT FROM AUTHOR]

Simple Summary: The effects of prolonged protein deprivation on lipid metabolism in white adipose tissues and the gut microbiota of Shaziling pigs remain inadequately characterized. As an ideal obese model, the Shaziling pig is instrumental in studying obesity. This study was developed to examine the changes in lipid metabolism and the gut microbiota ecosystem induced by prolonged protein deficiency of Shaziling pigs and to explore the beneficial effects of low-protein diets for obesity management. After a 24-week trial, increased FABP4 mRNA abundance and PPARγ protein expression as well as decreased C/EBPα protein expression in dorsal subcutaneous adipose tissue and perirenal adipose tissue were achieved through a 20% reduction in the dietary protein level. At the same time, increased/decreased phosphorylation of AMPKα/mTOR were observed. Furthermore, reducing the protein level by 20% increased the relative abundance of the Lachnospiraceae XPB1014 group in the colon at the genus level. In summary, our findings indicated that long-term reduction in dietary crude protein by 20% positively impacted the lipid metabolism of Shaziling pigs. Obesity is a matter of concern to the public. Abundant evidence has been accumulated that nutritional intervention is a promising strategy to address this health issue. The objective of this study is to investigate alterations in the lipid metabolism in white adipose tissues and the gut microbiota of Shaziling pigs challenged by long-term protein restriction. Results showed that compared with the control group, reducing the protein level by 20% (−20%) increased the mRNA abundance of FABP4 in white adipose tissues (p < 0.05). This occurred in conjunction with increases in PPARγ protein expression. Conversely, the protein expression of C/EBPα was reduced in the −20% group (p < 0.05). Moreover, the −20% group had increased/decreased phosphorylation of AMPKα/mTOR, respectively (p < 0.05). As for the colonic gut microbiota, a 20% reduction in the protein level led to increased Lachnospiraceae XPB1014 group abundance at the genus level (p < 0.01). Collectively, these results indicated that a 20% protein reduction could modulate lipid metabolism and alter the colonic microbiota of Shaziling pigs, an approach which might be translated into a treatment for obesity. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of lipopolysaccharide (LPS)-induced chronic immune stress on intestinal morphology and function, immune system, oxidative status, and mitochondrial function in piglets. Fifty healthy Duroc × Landrace × Yorkshire piglets (21 ± 2 days old, barrow, 6.98 ± 0.14 kg body weight) were selected and randomly allotted to five groups, which were slaughtered at 0 (0 group), 1, 5, 9, and 15 d of LPS injection. The results showed that compared with the piglets without LPS injection, LPS injection significantly impaired the intestinal morphology and permeability at 1, 5, and 9 d, as manifested by the increased serum lactic acid and decreased ratio of villus height to crypt depth (p < 0.05). Moreover, intestinal inflammation and oxidative and mitochondrial injury were caused at 1 d, as manifested by upregulated IL-6 mRNA expression, increased malondialdehyde content, and impaired mitochondrial morphology (p < 0.05). However, these parameters were restored to levels identical to 0 group at 9~15 d, accompanied by significantly increased antioxidant capacity, enhanced protein expression of CD3+ and CD68+, and upregulated mRNA abundance of genes related to mitochondrial biogenesis and functions (p < 0.05). Collectively, these results suggest that the intestinal injury of piglets caused by chronic immune stress could be self-repaired. [ABSTRACT FROM AUTHOR]

Simple Summary: The effects of long-term protein restriction on meat quality of Shaziling pigs and the underlying mechanism remain relatively unexplored. The aim of this study is to investigate the changes in meat quality and muscle metabolites of Shaziling pigs under the condition of low-protein diets and to provide a practical nutritional manipulation for swine production. After a 24-week trial, we found that reducing dietary crude protein by 20% led to improved meat quality (the reduced L* value and the increased a* value) and altered metabolite profiles of longissimus thoracis, without impairing growth performance and carcass traits. Moreover, results showed that the improvement on meat quality might be credited to diminished concentrations of Danazol, N,N-dimethyl-Safingol, and cer(d18:0/14:0). Our findings suggested long-term protein restriction (20% reduction) is suitable to improve meat quality and sustain growth performance. Background: It has been demonstrated that low-protein diets can improve the meat quality of pork. This study aimed to investigate the effects of long-term protein restriction from piglets to finishing pigs for 24 weeks on meat quality and muscle metabolites of Shaziling pigs. Results: Compared to the control group, reducing dietary protein levels by 20% reduced the L* value (p < 0.05), increased the a* value (p < 0.01), and tended to decrease pressing loss (p = 0.06) of longissimus thoracis muscle (LTM). Furthermore, compared to the control group, the −20% group had significantly lower levels of muscular danazol, N,N-dimethyl-Safingol, and cer(d18:0/14:0) (p < 0.05), all of which were positively associated with the L* value and negatively associated with the a* value (p < 0.05). Therefore, danazol, N,N-dimethyl-Safingol, and cer(d18:0/14:0) might be potential biomarkers for meat color. Conclusions: These results indicated that reducing dietary crude protein by 20% for 24 weeks could improve meat quality and alter muscular metabolites of Shaziling pigs, and the improvement in meat quality might be ascribable to decreased danazol, N,N-dimethyl-Safingol and cer(d18:0/14:0). [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the effect of dietary taurine on lipid metabolism and liver injury in mice fed a diet high in oxidized fish oil. The ICR mice (six weeks old) were randomly assigned to six groups and fed different diets for 10 weeks: control (CON), normal plus 15% fresh fish oil diet (FFO), normal plus 15% oxidized fish oil diet (OFO), or OFO plus 0.6% (TAU1), 0.9% (TAU2) or 1.2% (TAU3) taurine. Compared to the CON group, OFO mice showed increased liver index, aspartate aminotransferase (AST) and malondialdehyde (MDA) levels in serum (p < 0.05). In addition, OFO mice had increased cholesterol (CHOL)/high-density lipoprotein cholesterol (HDL-C) and decreased HDL-C/low-density lipoprotein cholesterol (LDL-C) and n-6/n-3 polyunsaturated fatty acid (PUFA) ratio in serum (p < 0.05) compared with CON mice. Notably, dietary taurine ameliorated the liver index and AST and MDA levels in serum and liver in a more dose-dependent manner than OFO mice. In addition, compared to OFO mice, decreased levels of CHOL and ratio of CHOL/HDL-C and n-6 PUFA/n-3 PUFA in serum were found in TAU3-fed mice. Supplementation with TAU2 and TAU3 increased the relative mRNA expression levels of peroxisome proliferator-activated receptor α, adipose triglyceride lipase, lipoprotein lipase, hormone-sensitive lipase and carnitine palmitoyl transferase 1 in liver compared with the OFO group (p < 0.05). Moreover, impaired autophagy flux was detected in mice fed with the OFO diet, and this was prevented by taurine. These findings suggested that dietary taurine might provide a potential therapeutic choice against oxidative stress and lipid metabolism disorder. [ABSTRACT FROM AUTHOR]

This study examined the effects of dietary leucine supplements on antioxidant capacity and meat quality in growing-finishing pigs. A total of 24 crossbred (Duroc × Landrace × Yorkshire) pigs with an average initial weight of 68.33 ± 0.97 kg were randomly allotted to three treatment groups. All pigs were exposed to constant heat stress. Each group of pigs was fed a basal diet, or a diet supplemented with increasing levels of leucine (0.25% or 0.50%). The results showed that leucine intake could improve average daily gain and reduce feed/gain of finishing pigs under heat stress (p < 0.05). The supplementation of leucine could improve the carcass slant length (p = 0.09), and dramatically increased loin-eye area of the finishing pigs (p < 0.05) but had no significant effect on other carcass traits. Compared with the control group, 0.50% leucine markedly reduced drip loss and shear force of longissimus dorsi muscle, and increased pH value at 24 h after slaughter (p < 0.05). Dietary supplementation of 0.25% leucine increased the contents of inosine monophosphate and intramuscular fat in biceps femoris muscle (p < 0.05). Supplementation of 0.25% or 0.50% leucine significantly stimulated the activities of antioxidant enzymes while reduced the level of MDA in serum, liver and longissimus dorsi muscle (p < 0.05). Compared with the control group, 0.50% leucine supplementation markedly modulated the relative mRNA expression levels of genes related to muscle fiber type and mitochondrial function in longissimus dorsi muscle and the gene relative antioxidant in the liver (p < 0.05). In conclusion, dietary leucine supplementation could improve the growth performance and meat quality of the finishing pigs under heat stress, and the pathway of Keap1-NRF2 and PGC-1α-TFAM might be involved. [ABSTRACT FROM AUTHOR]

Based on the lift-to-drag ratio of a two-dimensional trajectory correction projectile, in this paper, a novel correction efficiency coefficient model has been proposed for the trajectory optimization of a two-dimensional trajectory correction projectile, and research on the influence a correction efficiency coefficient has on the flight parameters of correction trajectory is carried out. A series of results are obtained through theoretical analysis and simulation calculations, indicating that, the smaller the value of the correction efficiency coefficient is, the stronger the correction ability of the projectile reserves. The trajectory and canard geometry of the correction section of the two-dimensional trajectory correction projectile are optimized by the Gauss pseudo-spectral method and correction efficiency coefficient, and, after taking the correction efficiency coefficient into account, the projectile can accurately hit the target and effectively eliminate the swing phenomenon of the projectile's lateral trajectory. Meanwhile, a stable roll control command is obtained. When the diameter aspect ratio of the canard is 0.4, both the flight state quantity of the optimized projectile and the roll control command are more stable, and, when the canard shape is trapezoidal, the correction efficiency coefficient is smaller, the result of trajectory optimization is more stable, and the stability of the output roll control command is better. The research results of this paper can provide certain references for both the designs of the two-dimensional trajectory correction projectile's trajectory and the canard geometry. [ABSTRACT FROM AUTHOR]

Simple Summary: In China, and even the world, the animal husbandry industry is facing the problem of a shortage of feed ingredients, and even humans and animals compete for food. The development of unconventional feed resources is an urgent task. In our previous work, we analyzed the nutritional value of tea powder and believed that it has development potential. This study investigated the effects of supplementing different levels of tea powder in diets on pig growth performance, meat quality, and antioxidant properties. These results provide a preliminary basis for the application of tea powder as a supplement in animal husbandry. This study was conducted to evaluate the effects of tea powder in diets on the growth performance, meat quality, muscular amino acid, fatty acid profile, and serum biochemical indices of pigs. A total of 120 local Chinese pigs (Tibetan × Bama miniature pigs) were randomly assigned to five treatment groups, each with six pens and four pigs per pen. During a 60-day experiment, these groups of pigs were fed the normal diet and the diet supplemented with 1%, 2%, 4%, and 6% tea powder, respectively. The results showed that the supplementation of tea powder did not affect the growth performance of pigs. However, the dietary tea powder inclusion decreased (p < 0.05) the average fat thickness, total fat, and abdominal fat, and increased (p < 0.05) the total muscle as well. In addition, the dietary 2% tea powder decreased (p < 0.05) the muscle lightness (L*) and yellowness (b*). Compared with the control group, the dietary supplementation with 1%, 2%, and 4% tea powder raised (p < 0.05) the total amino acids (TAA) and essential amino acids (EAA), and dietary 4% and 6% tea powder increased (p < 0.05) the C20:5n3 in the muscle tissue. Furthermore, the serum lipid metabolism-related biochemical indices and mRNA expression levels were improved with the addition of tea powder. These results indicated that dietary tea powder might improve the carcass traits and meat quality of the Chinese native finishing pigs, but it does not affect their growth performance. Tea powder could be fully developed and reasonably applied as a dietary supplement. [ABSTRACT FROM AUTHOR]

Simple Summary: Pork is the most consumed meat source for humans, and the utilization of nutritional approaches to produce pork with an appropriate content of intramuscular fat (IMF) and a balanced ratio of different kinds of fatty acid is an important objective pursuit of swine production. We speculated that dietary supplementation of beta-hydroxy beta-methyl butyrate (HMB) may provide benefits in lipid metabolism of skeletal muscle. In this study, we try to investigate the effects of dietary HMB supplementation on muscular lipid metabolism in Bama Xiang mini-pigs. We found that HMB supplementation could decrease the IMF content and increase n3 polyunsaturated fatty acids as well as regulate the related metabolites (N-Methyl-l-glutamate and nummularine A) in the serum of Bama Xiang mini-pigs, thus improving their meat quality. This study aimed to investigate the effects of dietary beta-hydroxy beta-methyl butyrate (HMB) supplementation on muscular lipid metabolism in Bama Xiang mini-pigs. Thirty-two piglets (8.58 ± 0.40 kg, barrow) were selected and fed a basal diet supplemented either with 0 (control), 0.13%, 0.64%, or 1.28% HMB for 60 days. Throughout the experiments, they had free access to clean drinking water and diets. Data of this study were analyzed by one-way ANOVA using the SAS 8.2 software package, followed by a Tukey's studentized range test to explore treatment effects. The results showed that compared to the control, 0.13% HMB decreased the intramuscular fat (IMF) content and increased polyunsaturated fatty acids (PUFAs) in Longissimus thoracis muscle (LTM), and increased the n3 PUFAs in soleus muscles (SM, p < 0.05). Moreover, HMB supplementation led to alterations in the mRNA expression of genes related to lipid metabolism. Serum metabolome profiling showed that in both LTM and SM of Bama Xiang mini-pigs, N-Methyl-l-glutamate was positively correlated with SFA and nummularine A was negatively correlated with C18:3n3 PUFA (p < 0.05). Therefore, N-Methyl-l-glutamate and nummularine A might be potential biomarkers of the HMB-supplemented group. These results suggested that dietary HMB supplementation could decrease the IMF content and increase n3 PUFAs as well as regulate the related metabolites (N-Methyl-l-glutamate and nummularine A) in the serum of pigs. [ABSTRACT FROM AUTHOR]

Lipid metabolism is an important and complex biochemical process involved in the storage of energy and maintenance of normal biological functions. Leucine, a branched amino acid, has anti-obesity effects on glucose tolerance, lipid metabolism, and insulin sensitivity. Leucine also modulates mitochondrial dysfunction, representing a new strategy to target aging, neurodegenerative disease, obesity, diabetes, and cardiovascular disease. Although various studies have been carried out, much uncertainty still exists and further studies are required to fully elucidate the relationship between leucine and lipid metabolism. This review offers an up-to-date report on leucine, as key roles in both lipid metabolism and energy homeostasis in vivo and in vitro by acceleration of fatty acid oxidation, lipolysis, activation of the adenosine 5′-monophosphate-activated protein kinase (AMPK)–silent information regulator of transcription 1 (SIRT1)–proliferator-activated receptor γ coactivator-1α (PGC-1α) pathway, synthesis, and/or secretion of adipokines and stability of the gut microbiota. [ABSTRACT FROM AUTHOR]

Iron is a trace element necessary for cell growth, development, and cellular homeostasis, but insufficient or excessive level of iron is toxic. Intracellularly, sufficient amounts of iron are required for mitochondria (the center of iron utilization) to maintain their normal physiologic function. Iron deficiency impairs mitochondrial metabolism and respiratory activity, while mitochondrial iron overload promotes ROS production during mitochondrial electron transport, thus promoting potential disease development. This review provides an overview of iron homeostasis, mitochondrial iron metabolism, and how mitochondrial iron imbalances-induced mitochondrial dysfunction contribute to diseases.