Resveratrol attenuates mitochondrial dysfunction in the liver of intrauterine growth retarded suckling piglets by improving mitochondrial biogenesis and redox status

Neonatal resveratrol administration promotes skeletal muscle growth and insulin sensitivity in intrauterine growth-retarded suckling piglets associated with activation of FGF21-AMPKα pathway

BACKGROUND

Skeletal muscle is a major insulin-sensitive tissue with a pivotal role in modulating glucose homeostasis. This study aimed to investigate the effect of resveratrol (RES) intervention during the suckling period on skeletal muscle growth and insulin sensitivity of neonates with intrauterine growth retardation (IUGR) in a pig model.

RESULTS

Twelve pairs of normal birth weight (NBW) and IUGR neonatal male piglets were selected. The NBW and IUGR piglets were fed basal formula milk diet or identical diet supplemented with 0.1% RES from 7 to 21 days of age. Myofiber growth and differentiation, inflammation and insulin sensitivity in skeletal muscle were assessed. Early RES intervention promoted myofiber growth and maturity in IUGR piglets by ameliorating the myogenesis process and increasing thyroid hormone level. Administering RES also reduced triglyceride concentration in skeletal muscle of IUGR piglets, along with decreased inflammatory response, increased plasma fibroblast growth factor 21 (FGF21) concentration and improved insulin signaling. Meanwhile, the improvement of insulin sensitivity by RES may be partly regulated by activation of the FGF21/AMP-activated protein kinase α/sirtuin 1/peroxisome proliferator activated receptor-γ coactivator-1α pathway.

CONCLUSION

Our results suggest that RES has beneficial effects in promoting myofiber growth and maturity and increasing skeletal muscle insulin sensitivity in IUGR piglets, which open a novel field of application of RES in IUGR infants for improving postnatal metabolic adaptation. © 2023 Society of Chemical Industry.

Intrauterine growth restriction in piglets modulates postnatal immune function and hepatic transcriptional responses independently of energy intake

Introduction: Insufficient prenatal nutrition can affect fetal development and lead to intrauterine growth restriction (IUGR). The aim of this study was to investigate hepatic transcriptional responses and innate immune function in piglets suffering from IUGR compared to normal-sized piglets at 3 days of age and explore whether the provision of an energy-rich supplement at birth could modulate these parameters. Methods: A total of 68 piglets were included in the study. Peripheral blood mononuclear cells were harvested for LPS stimulation, and organs were harvested post-mortem to quantify relative weights. Liver tissue was utilized for RNA sequencing coupled with gene-set enrichment analysis. Results: IUGR resulted in increased expression of genes such as PDK4 and substantial alterations in transcriptional pathways related to metabolic activity (e.g., citric acid and Krebs cycles), but these changes were equivalent in piglets given an energy-rich supplement or not. Transcriptomic analysis and serum biochemistry suggested altered glucose metabolism and a shift toward oxidation of fatty acids. IUGR piglets also exhibited suppression of genes related to innate immune function (e.g., CXCL12) and pathways related to cell proliferation (e.g., WNT and PDGF signaling). Moreover, they produced less IL-1β in response to LPS stimulation and had lower levels of blood eosinophils than normal-sized piglets. Discussion: Taken together, our results indicate that IUGR results in early-life alterations in metabolism and immunity that may not be easily restored by the provision of exogenous energy supplementation.

Serine Administration Improves Selenium Status, Oxidative Stress, and Mitochondrial Function in Longissimus Dorsi Muscle of Piglets with Intrauterine Growth Retardation

Intrauterine growth retardation (IUGR) causes oxidative stress in the skeletal muscle. Serine and selenoproteins are involved in anti-oxidative processes; however, whether IUGR affects selenium status and whether serine has beneficial effects remain elusive. Here, we investigated the effects of serine administration on selenium nutritional status and oxidative stress in the longissimus dorsi muscle of piglets with IUGR. Six newborn Min piglets having normal birth weight were administered saline, and 12 IUGR piglets were either administered saline or 0.8% serine. The results showed a lower selenium content in skeletal muscle in IUGR piglets, which was restored after serine administration. IUGR piglets showed a disturbed expression of genes encoding selenoproteins, with decreased expression of GPX2, GPX4, TXNRD1, and TXNRD3 and increased expression of DIO1, DIO2, SELF, SELM, SELP, and SELW. Notably, serine administration restored the expression levels of these genes. In accordance with the changes in gene expression, the activity of GPX, TXNRD, and DIO and the content of GSH and SELP were also altered, whereas serine administration restored their contents and activities. Moreover, we observed severe oxidative stress in the skeletal muscle of IUGR piglets, as indicated by decreased GSH content and increased MDA and PC content, whereas serine administration alleviated these changes. In conclusion, our results indicate that IUGR piglets showed a disturbed expression of genes encoding selenoproteins, accompanied by severe oxidative stress. Serine administration can improve selenium status, oxidative stress, and mitochondrial function in the longissimus dorsi muscle of piglets with IUGR. These results suggest that serine could potentially be used in the treatment of IUGR in piglets.

Biological function of resveratrol and its application in animal production: a review

With the prohibition of antibiotics in feed, plant functional substances have been widely studied as feed additives. Resveratrol, a natural stilbene, and a non-flavonoid polyphenol found in plants, possesses antioxidant, anti-inflammatory, and metabolic regulatory features. Resveratrol generated intense scientific and public interest, primarily due to its widely reported ability to prevent cancer, delay aging and alleviate related metabolic diseases. Recently, resveratrol has been studied and applied as a feed additive in animal production. This review focuses on the outline of the absorption and metabolism and biological functions of resveratrol and summarizes the application of dietary resveratrol in animal production up to the present, including pigs, poultry, and ruminants. In pigs, dietary resveratrol improved intestinal health, mitochondrial function, meat quality, and more. In poultry, studies have shown that dietary resveratrol improves growth performance and meat and egg quality and alleviates heat stress induced adverse effects. There are few studies on dietary resveratrol in ruminants; however previous studies have indicated that dietary resveratrol increases nutrient digestibility and reduces methane emissions in sheep. It is hoped that this review could provide a specific theoretical basis and research ideas for the research and application of resveratrol.

Common pregnancy complications and polyphenols intake: an overview

During pregnancy, the body undergoes a great amount of changes in order to support a healthy developing fetus. In this context, maternal dietary supplementation is widely encouraged to provide adequate nutrition for the newborn. In the past few years, studies have emerged highlighting the benefits of polyphenols intake during pregnancy. Indeed, despite differences among reports, such as experimental model, polyphenol employed, dosage and regimen of administration, there is no doubt that the ingestion of these molecules has a protective effect in relation to three pregnancy-associated diseases or conditions: preeclampsia, gestational diabetes and fetal growth restriction. In this review, we describe the effects of different polyphenols and polyphenol-rich extracts or juices on the main outcomes of these common pregnancy-associated complications, obtained in human, animal and in vitro studies. Therefore, this work provides a critical analysis of the literature, and a summary of evidences, from which future research using polyphenols can be designed and evaluated.

Intrauterine growth retardation affects liver bile acid metabolism in growing pigs: effects associated with the changes of colonic bile acid derivatives

BACKGROUND

Intrauterine growth retardation (IUGR) is associated with severely impaired nutrient metabolism and intestinal development of pigs. Our previous study found that IUGR altered intestinal microbiota and metabolites in the colon. However, the consequences of IUGR on bile acid metabolism in pigs remained unclear. The present study aimed to investigate the bile acid metabolism in the liver and the profile of bile acid derivatives in the colon of growing pigs with IUGR using bile acid targeted metabolomics. Furthermore, we determined correlations between colonic microbiota composition and metabolites of IUGR and normal birth weight (NBW) pigs at different growth stages that were 7, 21, and 28-day-old, and the average body weight (BW) of 25, 50, and 100 kg of the NBW pigs.

RESULTS

The results showed that the plasma total bile acid concentration was higher (P < 0.05) at the 25 kg BW stage and tended to increase (P = 0.08) at 28-day-old in IUGR pigs. The hepatic gene expressions related to bile acid synthesis (CYP7A1, CYP27A1, and NTCP) were up-regulated (P < 0.05), and the genes related to glucose and lipid metabolism (ATGL, HSL, and PC) were down-regulated (P < 0.05) at the 25 kg BW stage in IUGR pigs when compared with the NBW group. Targeted metabolomics analysis showed that 29 bile acids and related compounds were detected in the colon of pigs. The colonic concentrations of dehydrolithocholic acid and apocholic acid were increased (P < 0.05), while isodeoxycholic acid and 6,7-diketolithocholic acid were decreased (P < 0.05) in IUGR pigs, when compared with the NBW pigs at the 25 kg BW stage. Moreover, Spearman's correlation analysis revealed that colonic Unclassified_[Mogibacteriaceae], Lachnospira, and Slackia abundances were negatively correlated (P < 0.05) with dehydrolithocholic acid, as well as the Unclassified_Clostridiaceae abundance with 6,7-diketolithocholic acid at the 25 kg BW stage.

CONCLUSIONS

These findings suggest that IUGR could affect bile acid and glucolipid metabolism in growing pigs, especially at the 25 kg BW stage, these effects being paralleled by a modification of bile acid derivatives concentrations in the colonic content. The plausible links between these modified parameters are discussed.

Altered Liver Metabolism, Mitochondrial Function, Oxidative Status, and Inflammatory Response in Intrauterine Growth Restriction Piglets with Different Growth Patterns before Weaning

Frequent occurrence of intrauterine growth restriction (IUGR) causes huge economic losses in the pig industry. Accelerated catch-up growth (CUG) in the early stage of life could restore multiple adverse outcomes of IUGR offspring; however, there is little knowledge about this beneficial phenomenon. We previously found that nutrient absorption related to intestinal function was globally promoted in CUG-IUGR piglets before weaning, which might be the dominant reason for CUG, but what this alteration could lead to in subsequent liver metabolism is still unknown. Firstly, a Normal, CUG, and non-catch-up growth (NCUG) piglet model before weaning was established by dividing eighty litters of newborn piglets into normal birth weight (NBW) and IUGR groups according to birth weight, and those piglets with IUGR but above-average weanling body weight were considered CUG, and the piglets with IUGR still below average body weight were considered NCUG at weaning day (d 26). Liver samples were collected and then systematically compared in glycolipid metabolism, mitochondrial function, antioxidant status, and inflammatory status among these three different growth models. Enhanced hepatic uptake of fatty acids, diminished de novo synthesis of fatty acids, and increased oxidation of fatty acids were observed in CUG livers compared to Normal and NCUG. In contrast, the NCUG liver showed enhanced glucose uptake and gluconeogenesis compared to Normal and CUG. We also observed deteriorating hepatic vacuolation in NCUG piglets, while increasing hepatic lipid deposition in CUG piglets. Besides, the expression of genes related to mitochondrial energy metabolism and biogenesis was reduced in CUG piglets and the phosphorylation level of AMPK was significantly higher compared to Normal (p < 0.05). Moreover, NCUG liver showed decreased T-AOC (p < 0.01) and GSH-PX (p < 0.05), increased MDA concentrations (p < 0.01), upregulated phosphorylation levels of ERK and NF-κB (p < 0.05), and elevated pro-inflammatory factors IL-1β, IL-6 and TNF-α (p < 0.05) compared to Normal. Furthermore, correlation analysis revealed a significant positive correlation between glucose metabolism and inflammatory factors, while a negative correlation between mitochondrial function-related genes and fatty acid transport. NGUG piglets showed simultaneous enhancement of glucose uptake and gluconeogenesis, as well as reduced antioxidant capacity and increased inflammatory status, whereas CUG comes at the expense of impaired hepatic mitochondrial function and pathological fat accumulation.

Zinc Oxide Nanoparticle Improves the Intestinal Function of Intrauterine Growth Retardation Finishing Pigs via Regulating Intestinal Morphology, Inflammation, Antioxidant Status and Autophagy

This study was to investigate effects of zinc oxide nanoparticle (Nano-ZnO) on growth, immunity, intestinal morphology and function of intrauterine growth retardation (IUGR) finishing pigs. Six normal birth weight (NBW) and 12 IUGR male piglets were obtained and weaned at 21 d. NBW-weaned piglets fed basal diets (NBW group), IUGR-weaned piglets allocated to two groups fed basal diets (IUGR group) and basal diets further supplemented 600 mg Zn/kg from Nano-ZnO (IUGR+Zn group), respectively. All pigs were slaughtered at 163 d. Results showed: (1) IUGR pigs showed no difference in body weight at 77d and 163d (P > 0.05), while had increased villus height (VH) and villus surface area in jejunum (P < 0.05) and enhanced interleukin-6, TNF-α and NF-κB mRNA expression (P < 0.05) as compared to NBW group; Compared with IUGR group, dietary Nano-ZnO did not affect the body weight (P > 0.05), but increased VH to crypt depth ratio and IgA concentration (P < 0.05) and decreased TNF-α and NF-κB mRNA expression in jejunum (P < 0.05). (2) IUGR increased the number of swollen mitochondria and autolysosomes, and protein expressions of sequestosome-1 (P62) and microtubule-associated protein light chain 3 B/A (LC3B/A) in jejunum as compared to NBW group (P < 0.05); Compared with IUGR group, Nano-ZnO decreased the number of swollen mitochondria and autolysosomes, and P62 and LC3B/A protein expression (P < 0.05). (3) IUGR increased mucosal contents of malondialdehyde and protein carbonyl (PC) and Keap1 protein expression (P < 0.05) as compared to NBW group; Compared with IUGR group, dietary Nano-ZnO increased activities of total antioxidant capacity, catalase, glutathione peroxidase, and glutathione content (P < 0.05), and enhanced nuclear respiratory factor 2 (Nrf2), glutamate-cysteine ligase modifier subunit and glutathione peroxidase 1 mRNA expression, and increased total and nuclear Nrf2 protein expression (P < 0.05), and decreased malondialdehyde and PC content, and Keap1 protein expression (P < 0.05) in jejunum. Results suggested that IUGR pigs showed postnatal catch-up growth and improved intestinal morphology, and dietary Nano-ZnO may further improve intestinal morphology, reduce inflammation, decrease autophagy and alleviate oxidative stress via Nrf2/Keap1 pathway in jejunum of IUGR pigs.

Review: Implication of redox imbalance in animal health and performance at critical periods, insights from different farm species

The process of oxidative stress occurs all over the production chain of animals and food products. This review summarises insights obtained in different farm species (pigs, ruminants, poultry, and fishes) to underpin the most critical periods for the venue of oxidative stress, namely birth/hatching and weaning/start-feeding phase. Common responses between species are also unravelled in periods of high physiological demands when animals are facing dietary deficiencies in specific nutrients, suggesting that nutritional recommendations must consider the modulation of responses to oxidative stress for optimising production performance and quality of food products. These conditions concern challenges such as heat stress, social stress, and inflammation. The magnitude of the responses is partly dependent on the prior experience of the animals before the challenge, reinforcing the importance of nutrition and other management practices during early periods to promote the development of antioxidant reserves in the animal. When these practices also improved the performance and health of the animal, this further confirms the central role played by oxidative stress in physiologically and environmentally induced perturbations. Difficulties in interpreting responses to oxidative stress arise from the fact that the indicators are only partly shared between studies, and their modulations may also be challenge-specific. A consensus about the best indicators to assess pro-oxidative and antioxidant pathways is of huge demand to propose a synthetic index measurable in a non-invasive way and interpretable along the productive life of the animals.

Resveratrol regulates Hsp60 in HEK 293T cells during activation of SIRT1 revealed by nascent protein labeling strategy

Background

Resveratrol, a well-known natural compound and nutrient, activates the deacetylation ability of SIRT1, demonstrating p53-dependent apoptosis functions in many diseases. However, the nascent proteomic fluctuation caused by resveratrol is still unclear.

Objective

In this study, we investigated the effect of resveratrol on the nascent proteome and transcriptome initiated by SIRT1 activation, and we explored the mechanism of resveratrol in HEK 293T cells.

Methods

Bioorthogonal noncanonical amino acid tagging (BONCAT) is a method used to metabolically label nascent proteins. In this strategy, L-azidohomoalanine (AHA) was used to replace methionine (Met) under different conditions. Taking advantage of the click reaction between AHA and terminal alkyne- and disulfide-functionalized agarose resin (TAD resin), we were able to efficiently separate stimulation responsive proteins from the pre-existing proteome. Resveratrol responsive proteins were identified by Liquid Chromatograph-Mass Spectrometer/Mass Spectrometer (LC-MS/MS). Furthermore, changes in mRNA levels were analyzed by transcriptome sequencing.

Results

Integrational analysis revealed a resveratrol response in HEK 293T cells and showed that Hsp60 was downregulated at both the nascent protein and mRNA levels. Knockdown of SIRT1 and Hsp60 provides evidence that resveratrol downregulated Hsp60 through SIRT1 and that Hsp60 decreased p53 through the Akt pathway.

Conclusions

This study revealed dynamic changes in the nascent proteome and transcriptome in response to resveratrol in HEK 293T cells and demonstrated that resveratrol downregulates Hsp60 by activating SIRT1, which may be a possible mechanism by which resveratrol prevents p53-dependent apoptosis by regulating Hsp60.

Polydatin Attenuates Intra-Uterine Growth Retardation-Induced Liver Injury and Mitochondrial Dysfunction in Weanling Piglets by Improving Energy Metabolism and Redox Balance

The present study investigated the potential of polydatin to protect against liver injury and the mitochondrial dysfunction of weanling piglets suffering from intra-uterine growth retardation (IUGR). Thirty-six normal birth weight weanling piglets and an equal number of IUGR littermates were given a basal diet with or without polydatin (250 mg/kg) from 21 to 35 d of age. Plasma and liver samples were collected to measure biochemistry parameters at 35 d of age. IUGR caused hepatic apoptosis, mitochondrial dysfunction, and oxidative damage, along with a lower efficiency of energy metabolism and inferior antioxidant ability. Polydatin decreased apoptotic rate, improved the features of mitochondrial damage, inhibited mitochondrial swelling and superoxide anion formation, and preserved mitochondrial membrane potential in the liver. Concurrently, polydatin promoted mitochondrial biogenesis, increased sirtuin 1 activity, and upregulated the expression levels of several genes related to mitochondrial function and fitness. Polydatin also facilitated mitochondrial oxidative metabolism with a beneficial outcome of increased energy production. Furthermore, polydatin mitigated the IUGR-induced reduction in manganese superoxide dismutase activity and prevented the excessive accumulation of oxidative damaging products in the liver. These findings indicate that polydatin confers protection against hepatic injury and mitochondrial dysfunction in the IUGR piglets by improving energy metabolism and redox balance.

Resveratrol Improves Intestinal Morphology and Anti-Oxidation Ability in Deoxynivalenol-Challenged Piglets

Simple Summary

Deoxynivalenol (DON)-contaminated feed may cause anorexia, vomiting, immunosuppression, and intestinal dysfunction in pigs, which would lead to growth retardation and great losses in the pig industry. In this study, the effects of resveratrol (RES) on growth performance, the intestinal barrier, antioxidant capacity, and mitochondrial function in weaned pigs fed with DON-contaminated diets were investigated. Dietary supplementation with resveratrol increased the average daily feed intake of piglets. Diets supplemented with resveratrol increased the villus height and the ratio of the jejunum villus height to crypt depth, increased the activities of superoxide dismutase (SOD), and increased the total antioxidant capacity in the jejunum mucosa. After being supplemented with RES, the level of reactive oxygen species (ROS) in mitochondria was decreased, while the mitochondrial membrane potential in the jejunum was increased. In conclusion, these results suggested that resveratrol effectively relieved DON-induced oxidative stress in weaned piglets, improved intestinal barrier function, enhanced mitochondrial function, and improved the growth performance of piglets.

Abstract

This study aimed to investigate the potential effects of resveratrol (RES) on intestinal function and oxidative stress in deoxynivalenol (DON)-challenged piglets. Twenty-four healthy Duroc × Yorkshire × Landrace weaned piglets at the age of 28 ± 1 days were randomly divided into four groups with six repetitions per group. The four groups were as follows: the control group (CON), fed with a basic diet; the RES group, fed with a basal diet + 300 mg/kg RES; the DON group, fed with a basal diet containing 2.65 mg/kg DON; and the DON + RES group, fed with a basal diet containing 2.65 mg/kg DON + 300 mg/kg RES. The results showed that the growth performance and intestinal function of DON-challenged piglets were significantly decreased (p < 0.05). Compared with the DON group, the average daily feed intake of piglets in the DON + RES group was significantly increased (p < 0.05). Additionally, dietary RES ameliorated DON-induced intestinal morphology impairment, as indicated by the increased (p < 0.05) jejunal villi height and the ratio of the jejunal villi height/crypt depth. Furthermore, after the addition of RES, the activities of superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) in the jejunum mucosa were significantly increased, and the content of malondialdehyde (MDA) was significantly declined (p < 0.05). In addition, the level of reactive oxygen species (ROS) in the mitochondria was significantly reduced by RES, while the mitochondrial membrane potential in jejunum was significantly increased by RES (p < 0.05). However, there was no obvious difference between DON + RES and DON groups on average daily gain and the ratio of feed togain, except for the significant inhibition of average daily feed intake (p < 0.05). In conclusion, RES could effectively alleviate the DON-induced oxidative stress on weaned piglets, and reduce the damage to mitochondria and intestinal morphology, so as to improve the growth performance of piglets.

Resveratrol and its derivative pterostilbene attenuate oxidative stress-induced intestinal injury by improving mitochondrial redox homeostasis and function via SIRT1 signaling

Oxidative stress inflicts mitochondrial dysfunction, which has been recognized as a key driver of intestinal diseases. Resveratrol (RSV) and its derivative pterostilbene (PTS) are natural antioxidants and exert a protective influence on intestinal health. However, the therapeutic effects and mechanisms of RSV and PTS on oxidative stress-induced mitochondrial dysfunction and intestinal injury remain unclear. The present study used porcine and cellular settings to compare the effects of RSV and PTS on mitochondrial redox homeostasis and function to alleviate oxidative stress-induced intestinal injury. Our results indicated that PTS was more potent than RSV in reducing oxidative stress, maintaining intestinal integrity, and preserving the mitochondrial function of diquat-challenged piglets. In the in vitro study, RSV and PTS protected against hydrogen peroxide (H₂O₂)-induced mitochondrial dysfunction in intestinal porcine enterocyte cell line (IPEC-J2) by facilitating mitochondrial biogenesis and increasing the activities of mitochondrial complexes. In addition, both RSV and PTS efficiently mitigated mitochondrial oxidative stress by increasing sirtuin 3 protein expression and the deacetylation of superoxide dismutase 2 and peroxiredoxin 3 in H₂O₂-exposed IPEC-J2 cells. Furthermore, RSV and PTS preserved mitochondrial membrane potential, which restrained the release of cytochrome C from mitochondria to the cytoplasm and caspase-3 activation and further reduced apoptotic rates in H₂O_2-exposed IPEC-J2 cells. Mechanistically, depletion of sirtuin 1 (SIRT1) abrogated RSV's and PTS's benefits against mitochondrial reactive oxygen species overproduction, mitochondrial dysfunction, and apoptosis in H₂O₂-exposed IPEC-J2 cells, suggesting that SIRT1 was required for RSV and PTS to protect against oxidative stress-induced intestinal injury. In conclusion, RSV and PTS improve oxidative stress-induced intestinal injury by regulating mitochondrial redox homeostasis and function via SIRT1 signaling pathway. In offering this protection, PTS is superior to RSV.

Role of stilbenes against insulin resistance: A review

Insulin resistance (IR) is a state characterized by the inability of tissues to utilize blood glucose particularly liver, muscle, and adipose tissues resulting in hyperglycemia and hyperinsulinemia. A close relationship exists between IR and the development of type 2 diabetes (T2D). Therefore, therapeutic approaches to treat IR also improve T2D simultaneously. Scientific evidence has highlighted the major role of inflammatory cytokines, reactive oxygen species (ROS), environmental & genetic factors, and auto-immune disorders in the pathophysiology of IR. Among therapeutic remedies, nutraceuticals like polyphenols are being used widely to ameliorate IR due to their safer nature compared to pharmaceutics. Stilbenes are considered important metabolically active polyphenols currently under the limelight of research to cope with IR. In this review, efforts are made to elucidate cellular and subcellular mechanisms influenced by stilbenes including modulating insulin signaling cascade, correcting glucose transport pathways, lowering postprandial glucose levels, and protecting β-cell damage and its effects on the hyperactive immune system and proinflammatory cytokines to attenuate IR. Furthermore, future directions to further the research in stilbenes as a strong candidate against IR are included so that concrete recommendation for their use in humans is made.

Dietary N-carbamylglutamate or l-arginine supplementation improves hepatic energy status and mitochondrial function and inhibits the AMP-activated protein kinase-peroxisome proliferator-activated receptor γ coactivator-1α-transcription factor A pathway in intrauterine-growth-retarded suckling lambs

The objective of this study was to investigate the effects of dietary administration of l-arginine (Arg) or N-carbamylglutamate (NCG) on hepatic energy status and mitochondrial functions in suckling Hu lambs with intrauterine growth retardation (IUGR). Forty-eight newborn Hu lambs of 7 d old were allocated into 4 treatment groups of 12 lambs each, in triplicate with 4 lambs per replicate (2 males and 2 females) as follows: CON (lambs of normal birth weight, 4.25 ± 0.14 kg), IUGR (3.01 ± 0.12 kg), IUGR + 1% Arg (2.99 ± 0.13 kg), or IUGR + 0.1% NCG (3.03 ± 0.11 kg). The experiment lasted for 21 d, until d 28 after birth, and all lambs were fed milk replacer as a basal diet. Compared with IUGR lambs, NCG or Arg administration increased (P < 0.05) the adenosine triphosphate (ATP) level and the activities of complexes I/III/IV, isocitrate dehydrogenase and citrate synthase in the liver. Compared with CON lambs, the relative mRNA levels of adenosine monophosphate-activated protein kinase α1 (AMPKα1), peroxisome proliferator-activated receptor γ coactivator-1α (PGC1α) and transcription factor A (TFAM) were increased (P < 0.05) in the liver of IUGR lambs, but were decreased (P < 0.05) in the liver of NCG- or Arg-treated lambs compared with those in the IUGR lambs. Compared with IUGR lambs, NCG or Arg administration decreased (P < 0.05) the total AMPKα (tAMPKα)-to-phosphorylated AMPKα (pAMPKα) ratio and the protein expression of PGC1α and TFAM. The results suggested that dietary Arg or NCG supplements improved hepatic energy status and mitochondrial function and inhibited the AMPK-PGC1α-TFAM pathway in IUGR suckling lambs.

Dietary resveratrol attenuation of intestinal inflammation and oxidative damage is linked to the alteration of gut microbiota and butyrate in piglets challenged with deoxynivalenol

Background

Deoxynivalenol (DON) is a widespread mycotoxin that induces intestinal inflammation and oxidative stress in humans and animals. Resveratrol (RES) effectively exerts anti-inflammatory and antioxidant effects. However, the protective effects of RES on alleviating DON toxicity in piglets and the underlying mechanism remain unclear. Therefore, this study aimed to investigate the effect of RES on growth performance, gut health and the gut microbiota in DON-challenged piglets. A total of 64 weaned piglets [Duroc × (Landrace × Yorkshire), 21-d-old, 6.97 ± 0.10 kg body weight (BW)] were randomly allocated to 4 treatment groups (8 replicate pens per treatment, each pen containing 2 males; n = 16 per treatment) for 28 d. The piglets were fed a control diet (CON) or the CON diet supplemented with 300 mg RES/kg diet (RES group), 3.8 mg DON/kg diet (DON) or both (DON+RES) in a 2 × 2 factorial design.

Results

DON-challenged piglets fed the RES-supplemented diet had significantly decreased D-lactate concentrations and tumor necrosis factor alpha (TNF-α) and interleukin 1 beta (IL-1β) mRNA and protein expression, and increased zonula occludens-1 (ZO-1) mRNA and protein expression compared with those of DON-challenged piglets fed the unsupplemented diet (P < 0.05). Compared with unsupplemented DON-challenged piglets, infected piglets fed a diet with RES showed significantly decreased malondialdehyde (MDA) levelsand increased mRNA expression of antioxidant enzymes and antioxidant genes (i.e., GCLC, GCLM, HO-1, SOD1 and NQO-1) and glutamate-cysteine-ligase modulatory subunit (GCLM) protein expression (P < 0.05). Moreover, RES supplementation significantly abrogated the increase in the proportion of TUNEL-positive cells and the protein expression of caspase3 in DON-challenged piglets (P < 0.05). Finally, RES supplementation significantly increased the abundance of Roseburia and butyrate concentrations, while decreasing the abundances of Bacteroides and unidentified-Enterobacteriaceae in DON-challenged piglets compared with DON-challenged piglets alone (P < 0.05).

Conclusions

RES supplementation improved gut health in DON-challenged piglets by strengthening intestinal barrier function, alleviating intestinal inflammation and oxidative damage, and positively modulating the gut microbiota. The protective effects of RES on gut health may be linked to increased Roseburia and butyrate concentrations, and decreased levels of Bacteroides and unidentified-Enterobacteriaceae.

Simultaneous determination of cellular adenosine nucleotides, malondialdehyde, and uric acid using HPLC

Adenine nucleotides and malondialdehyde (MDA) are key components involved in energy metabolism and reactive oxygen species (ROS) production. Measuring the levels of these components at the same time would be critical in studying mitochondrial functions. We have established a HPLC method to simultaneously measure adenosine triphosphate, adenosine diphosphate, adenosine monophosphate, MDA, and uric acid (UA). The samples were treated with perchloric acid followed by centrifugation. After neutralization, the supernatant was subjected to HPLC determination. HPLC was performed using a C18 chromatographic column, isocratic elusion, and UV detection. The detection and quantification limits for these components were determined with standard solutions. The precision, repeatability, and 24-h stability were evaluated using cellular samples, and their relative standard deviations were all within 2%. The reproducibility and efficiency were confirmed with sample recovery tests and the observed oxidative effects of H₂ O₂ on Jurkat cells. With this method, we discovered the dependence of energy and oxidative states on the density of Jurkat cells cultured in suspension. We also found a significant correlation between UA in serum and that in saliva. These results indicate that this method has good accuracy and applicability. It can be used in biological, pharmacological, and clinical studies, especially those involving mitochondria, ROS, and purinergic signaling.

Resveratrol, Metabolic Dysregulation, and Alzheimer's Disease: Considerations for Neurogenerative Disease

Alzheimer’s disease (AD) has traditionally been discussed as a disease where serious cognitive decline is a result of Aβ-plaque accumulation, tau tangle formation, and neurodegeneration. Recently, it has been shown that metabolic dysregulation observed with insulin resistance and type-2 diabetes actively contributes to the progression of AD. One of the pathologies linking metabolic disease to AD is the release of inflammatory cytokines that contribute to the development of brain neuroinflammation and mitochondrial dysfunction, ultimately resulting in amyloid-beta peptide production and accumulation. Improving these metabolic impairments has been shown to be effective at reducing AD progression and improving cognitive function. The polyphenol resveratrol (RSV) improves peripheral metabolic disorders and may provide similar benefits centrally in the brain. RSV reduces inflammatory cytokine release, improves mitochondrial energetic function, and improves Aβ-peptide clearance by activating SIRT1 and AMPK. RSV has also been linked to improved cognitive function; however, the mechanisms of action are less defined. However, there is evidence to suggest that chronic RSV-driven AMPK activation may be detrimental to synaptic function and growth, which would directly impact cognition. This review will discuss the benefits and adverse effects of RSV on the brain, highlighting the major signaling pathways and some of the gaps surrounding the use of RSV as a treatment for AD.

Weaning differentially affects mitochondrial function, oxidative stress, inflammation and apoptosis in normal and low birth weight piglets

Weaning is associated with increased occurrence of infections and diseases in piglets. Recent findings indicate that weaning induces mitochondrial dysfunction and oxidative stress conditions that more severely impact smaller piglets. The objective of this study was to characterize the molecular mechanisms underlying these physiological consequences and the relation with systemic inflammatory status in both normal and low birth weight (NBW and LBW) piglets throughout the peri-weaning period. To conduct the study, 30 sows were inseminated, and specific piglets from their litters were assigned to one of two experimental groups: NBW (n = 60, 1.73 ± 0.01 kg,) and LBW piglets weighing less than 1.2 kg (n = 60, 1.01 ± 0.01 kg). Then, 10 piglets from each group were selected at 14, 21 (weaning), 23, 25, 29 and 35 days of age to collect organ and plasma samples. Specific porcine RT2 Profiler™ PCR Arrays related to mitochondrial function, oxidative stress, inflammation and apoptosis processes were first used to target genes that are modulated after weaning in NBW piglets (d 23 and d 35 vs. d 14). Expression of selected genes was evaluated by quantitative PCR. These analyses revealed that expression of inflammatory genes CXCL10 and CCL19 increased after weaning in intestinal mucosa, while expression of genes encoding subunits of the mitochondrial respiratory chain was downregulated in liver and kidney of both groups. Interestingly, major modulators of mitophagy (BNIP3), cell survival (BCL2A1) and antioxidant defense system (TXNRD2, GPx3, HMOX1) were found to be highly expressed in NBW piglets. The systemic levels of TNF-α and IL1-β significantly increased following weaning and were higher in NBW piglets. These results provide novel information about the molecular origin of mitochondrial dysfunction and oxidative stress observed in weaned piglets and suggest that clearance of dysfunctional mitochondria, antioxidant defenses and inflammatory response are compromised in LBW piglets.

Improvement of the hepatic lipid status in intrauterine growth retarded pigs by resveratrol is related to the inhibition of mitochondrial dysfunction, oxidative stress and inflammation

Mitochondrial dysfunction, oxidative stress and inflammation are crucial contributors to liver damage and nonalcoholic fatty liver disease (NAFLD) in adulthood in offspring affected by intrauterine growth retardation (IUGR). Resveratrol (RSV) has been reported to treat and/or prevent hepatic diseases under various pathological conditions. However, the therapeutic and/or preventive effects of RSV on hepatic abnormality in IUGR adults have not been investigated until now. The effects of IUGR and RSV on the hepatic metabolic status, mitochondrial function, redox homeostasis and inflammation in pigs in adulthood were investigated. A total of 36 pairs of IUGR and normal birth weight piglets were orally fed with 80 mg RSV per kg body weight per d or vehicle (0.5% carboxymethylcellulose) for 7-21 d after birth. And then the offspring were fed with a basal diet supplemented with 300 mg RSV per kg feed or a basal diet from weaning to slaughter at 150 d. The plasma and liver samples were collected for subsequent analysis. RSV exerted beneficial effects on hepatic injury and metabolic alterations in IUGR pigs, which may be due to improved mitochondrial function and fatty acid oxidation by intensified mitochondrial biogenesis, enhanced antioxidant levels such as glutathione reductase and total superoxide dismutase activities, increased interleukin 10 gene expression and repolarization of macrophages. RSV alleviated hepatic lipid accumulation in IUGR pigs by improving mitochondrial function, redox status and inflammation, implying that it is a potential candidate for further development as an effective clinical treatment for NAFLD associated with IUGR.

Protective Effect of Polydatin on Jejunal Mucosal Integrity, Redox Status, Inflammatory Response, and Mitochondrial Function in Intrauterine Growth-Retarded Weanling Piglets

Intrauterine growth retardation (IUGR) delays the gut development of neonates, but effective treatment strategies are still limited. This study used newborn piglets as a model to evaluate the protective effect of polydatin (PD) against IUGR-induced intestinal injury. In total, 36 IUGR piglets and an equal number of normal birth weight (NBW) littermates were fed either a basal diet or a PD-supplemented diet from 21 to 35 days of age. Compared with NBW, IUGR induced jejunal damage and barrier dysfunction of piglets, as indicated by observable bacterial translocation, enhanced apoptosis, oxidative and immunological damage, and mitochondrial dysfunction. PD treatment decreased bacterial translocation and inhibited the IUGR-induced increases in circulating diamine oxidase activity (P = 0.039) and D-lactate content (P = 0.004). The apoptotic rate (P = 0.024) was reduced by 35.2% in the PD-treated piglets, along with increases in villus height (P = 0.033) and in ratio of villus height to crypt depth (P = 0.049). PD treatment promoted superoxide dismutase (P = 0.026) and glutathione S-transferase activities (P = 0.006) and reduced malondialdehyde (P = 0.015) and 8-hydroxy-2′-deoxyguanosine accumulation (P = 0.034) in the jejunum. The PD-treated IUGR piglets showed decreased jejunal myeloperoxidase activity (P = 0.029) and tumor necrosis factor alpha content (P = 0.035) than those received a basal diet. PD stimulated nuclear sirtuin 1 (P = 0.028) and mitochondrial citrate synthase activities (P = 0.020) and facilitated adenosine triphosphate production (P = 0.009) in the jejunum of piglets. Furthermore, PD reversed the IUGR-induced declines in mitochondrial DNA content (P = 0.048), the phosphorylation of adenosine monophosphate-activated protein kinase alpha (P = 0.027), and proliferation-activated receptor gamma coactivator 1 alpha expression (P = 0.033). Altogether, the results indicate that PD may improve jejunal integrity, mitigate mucosal oxidative and immunological damage, and facilitate mitochondrial function in IUGR piglets.

Resveratrol Improves Hepatic Redox Status and Lipid Balance of Neonates with Intrauterine Growth Retardation in a Piglet Model

Abnormal lipid metabolism, oxidative stress (OS), and inflammation play a pivotal role in the increased susceptibility to neonatal fatty liver diseases associated with intrauterine growth retardation (IUGR). This study was firstly conducted to investigate whether resveratrol could alleviate IUGR-induced hepatic lipid accumulation, alteration of redox and immune status in a sucking piglet model and explore the possible mechanisms at transcriptional levels. A total of 36 pairs of 7 d old male normal birth weight (NBW) and IUGR piglets were orally fed with either 80 mg resveratrol/kg body weight/d or 0.5% carboxymethylcellulose sodium for a period of 14 days, respectively. Compared with the NBW piglets, the IUGR piglets displayed compromised growth performance and liver weight, reduced plasma free fatty acid (FFA) level, increased hepatic OS, abnormal hepatic lipid accumulation and weakened hepatic immune function, and hepatic aberrant transcriptional expression of some genes such as heme oxygenase 1, superoxide dismutase 1, sterol regulatory element-binding protein 1c, stearoyl-CoA desaturase 1, liver fatty acid-binding proteins 1, toll-like receptor 4, and tumor necrosis factor alpha (TNF-α). Oral administration of resveratrol to piglets decreased the levels of FFA and total triglycerides (TG) in the plasma and hepatic TNF-α concentration, and increased glutathione reductase activity and reduced glutathione level in the liver. Resveratrol restored the increased alanine aminotransferase activity in the plasma of IUGR piglets. Treatment with resveratrol ameliorated the increased hepatic malondialdehyde, protein carbonyl, TG, and FFA concentrations induced by IUGR. Resveratrol treatment alleviated the reduced lipoprotein lipase activity and its mRNA expression as well as TNF-α gene expression in the liver of IUGR piglets. Hepatic glutathione peroxidase 1 and monocyte chemotactic protein 1 genes expression of piglets was upregulated by oral resveratrol administration. In conclusion, resveratrol administration plays a beneficial role in hepatic redox status and lipid balance of the IUGR piglets.

Postnatal growth retardation is associated with intestinal mucosa mitochondrial dysfunction and aberrant energy status in piglets

Individuals with postnatal growth retardation (PGR) are prone to developing chronic disease. Abnormal development in small intestine is casually implicated in impaired growth performance. However, the exact mechanism is still unknown. In this present study, PGR piglets (aged 42 days) were employed as a good model to analyse changes in nutrient absorption and energy metabolism in the intestinal mucosa. The results showed lower serum concentrations of free amino acids, and lipid metabolites in PGR piglets, which were in accordance with the down‐regulated mRNA expressions involved in fatty acid and amino acid transporters in the jejunal and ileal mucosa. The decreased activities of digestive enzymes and the marked swelling in mitochondria were also observed in the PGR piglets. In addition, it was found that lower ATP production, higher AMP/ATP ratio, deteriorated mitochondrial complex III and ATP synthase, and decreased manganese superoxide dismutase activity in the intestinal mucosa of PGR piglets. Furthermore, altered gene expression involved in energy metabolism, accompanied by decreases in the protein abundance of SIRT1, PGC‐1α and PPARγ, as well as phosphorylations of AMPKα, mTOR, P70S6K and 4E‐BP1 were observed in intestinal mucosa of PGR piglets. In conclusion, decreased capability of nutrient absorption, mitochondrial dysfunction, and aberrant energy status in the jejunal and ileal mucosa may contribute to PGR piglets.

Resveratrol improves meat quality, muscular antioxidant capacity, lipid metabolism and fiber type composition of intrauterine growth retarded pigs

This study investigated whether resveratrol could improve meat quality, muscular antioxidant capacity, lipid metabolism and fiber type composition of intrauterine growth retarded pigs. Thirty-six pairs of male normal birth weight and intrauterine growth retardation (IUGR) piglets were orally fed with 80 mg resveratrol/kg body weight/d or vehicle during the sucking period (7-21 d). Then the offspring were fed with a basal diet containing 300 mg resveratrol/kg or a basal diet from weaning to slaughter (150 d). The IUGR-impaired meat quality (luminance and yellowness) was associated with muscular oxidative stress via increased Keap1 protein level, fat accumulation, and higher MyHC IIb gene expression. Expectedly, resveratrol increased glutathione peroxidase activity and MyHC I gene expression, reduced protein carbonyl and malondialdehyde contents, enhanced fatty acid oxidation via upregulated PPARα and targeted genes expression, and thereby improving drip loss and yellowness. Results indicate that resveratrol improved meat quality of IUGR pigs through enhancing antioxidant capacity, increasing oxidative fiber composition, and suppressing lipid accumulation.

Pterostilbene attenuates liver injury and oxidative stress in intrauterine growth-retarded weanling piglets

OBJECTIVES

The aim of the present study was to investigate the potential of pterostilbene, a beneficial component primarily found in blueberries, to alleviate the intrauterine growth retardation (IUGR)-induced early liver injury and oxidative stress in a porcine model.

METHODS

Thirty-six IUGR piglets and an equal number of normal birth weight (NBW) counterparts received a diet with or without pterostilbene (250 mg/kg diet) during the first week post-weaning. Parameters related to the hepatic injury, oxidative stress, and antioxidant defense mechanisms were analyzed.

RESULTS

Relative to NBW, IUGR induced liver injury, which corresponded to increments in circulating alanine transaminase activity and hepatic apoptotic cell rate, superoxide radical generation, and the accumulation of oxidative damage products (P < 0.05). Administering pterostilbene reduced plasma transaminase activities, decreased hepatocyte apoptosis rate, and prevented the augmented levels of hepatic superoxide anion, 8-hydroxy-2 deoxyguanosine, and 4-hydroxynonenal-modified protein (P < 0.05). In terms of the hepatic antioxidant function, pterostilbene was efficient in improving the superoxide dismutase activity and the metabolic cycle between reduced glutathione and its oxidized form (P < 0.05). The pterostilbene-supplemented diet facilitated the nuclear translocation of nuclear factor erythroid-2-related factor 2 (NRF2) and promoted the expression levels of superoxide dismutase 2 in the liver of IUGR piglets (P < 0.05).

CONCLUSION

This study indicates that pterostilbene treatment has an auxiliary therapeutic potential to ameliorate early liver injury in IUGR neonates, presumably by stimulating the NRF2 signals and the associated antioxidant function.

Effects of resveratrol on the levels of ATP, 5-HT and GAP-43 in the hippocampus of mice exposed to chronic unpredictable mild stress

Growing evidence suggested that energy deficiency might be involved in the pathophysiological mechanism of depression. Energy deficiency, mainly results from mitochondrial damage, can lead to the dysfunction of synaptic neurotransmission, and further cause depressive-like behavior. The antidepressant effect of resveratrol had been widely demonstrated in previous studies; however, the underlying mechanism remains poorly understood. The present study aimed to investigate whether the antidepressant effects of resveratrol involved in the energy levels and neurotransmission in the hippocampus. We found that resveratrol and fluoxetine significantly attenuated depressive-like behaviors induced by chronic unpredictable mild stress (CUMS), which evidenced by the increased sucrose preference and the reduced immobility time in a forced swimming test. In addition, resveratrol increased hippocampal ATP levels, decreased Na⁺-K⁺-ATPase and pyruvate levels, and upregulated the levels of mitochondrial DNA (mtDNA), mRNA expression of sirtuin (SIRT)1 and peroxisome proliferator-activated receptor γ coactivator (PGC)1α. Furthermore, resveratrol and fluoxetine increased serotonin (5-HT) levels and downregulated the mRNA expression of 5-HT transporter (SERT) in the hippocampus. The decreased protein expression of growth-associated protein (GAP)-43 induced by CUMS was also ameliorated by resveratrol and fluoxetine. These findings demonstrated the antidepressant effects of resveratrol and suggested that resveratrol was able to promote mitochondrial biogenesis, enhance ATP and 5-HT levels, as well as upregulate GAP-43 expression in the hippocampus.

Protective effects of taurine against muscle damage induced by diquat in 35 days weaned piglets

Background

Oxidative stress is a key factor that influences piglets’ health. Taurine plays an imperative role in keeping the biological system from damage. This study was conducted to investigate the protective effect of taurine against muscle injury due to the secondary effect of diquat toxicity.

Results

Our study found that taurine effectively and dose-dependently alleviated the diquat toxicity induced rise of feed/gain, with a concurrent improvement of carcass lean percentage. The plasma content of taurine was considerably increased in a dose-dependent manner. Consequently, dietary taurine efficiently improved the activity of plasma antioxidant enzymes. Furthermore, taurine attenuated muscle damage by restoring mitochondrial micromorphology, suppressing protein degradation and reducing the percentage of apoptotic cells in the skeletal muscle. Taurine supplementation also suppressed the genes expression levels of the antioxidant-, mitochondrial biogenesis-, and muscle atrophy-related genes in the skeletal muscle of piglets with oxidative stress.

Conclusions

These results showed that the dose of 0.60% taurine supplementation in the diet could attenuate skeletal muscle injury induced by diquat toxicity. It is suggested that taurine could be a potential nutritional intervention strategy to improve growth performance.

Resveratrol can enhance osteogenic differentiation and mitochondrial biogenesis from human periosteum-derived mesenchymal stem cells

Background

Osteoporosis is a metabolic bone disorder that leads to low bone mass and microstructural deterioration of bone tissue and increases bone fractures. Resveratrol, a natural polyphenol compound, has pleiotropic effects including anti-oxidative, anti-aging, and anti-cancer effects. Resveratrol also has roles in increasing osteogenesis and in upregulating mitochondrial biogenesis of bone marrow-derived mesenchymal stem cells (BM-MSCs). However, it is still unclear that resveratrol can enhance osteogenic differentiation or mitochondrial biogenesis of periosteum-derived MSCs (PO-MSCs), which play key roles in bone tissue maintenance and fracture healing. Thus, in order to test a possible preventive or therapeutic effect of resveratrol on osteoporosis, this study investigated the effects of resveratrol treatments on osteogenic differentiation and mitochondrial biogenesis of PO-MSCs.

Methods

The optimal doses of resveratrol treatment on PO-MSCs were determined by cell proliferation and viability assays. Osteogenic differentiation of PO-MSCs under resveratrol treatment was assessed by alkaline phosphatase activities (ALP, an early biomarker of osteogenesis) as well as by extracellular calcium deposit levels (a late biomarker). Mitochondrial biogenesis during osteogenic differentiation of PO-MSCs was measured by quantifying both mitochondrial mass and mitochondrial DNA (mtDNA) contents.

Results

Resveratrol treatments above 10 μM seem to have negative effects on cell proliferation and viability of PO-MSCs. Resveratrol treatment (at 5 μM) on PO-MSCs during osteogenic differentiation increased both ALP activities and calcium deposits compared to untreated control groups, demonstrating an enhancing effect of resveratrol on osteogenesis. In addition, resveratrol treatment (at 5 μM) during osteogenic differentiation of PO-MSCs increased both mitochondrial mass and mtDNA copy numbers, indicating that resveratrol can bolster mitochondrial biogenesis in the process of PO-MSC osteogenic differentiation.

Conclusion

Taken together, the findings of this study describe the roles of resveratrol in promoting osteogenesis and mitochondrial biogenesis of human PO-MSCs suggesting a possible application of resveratrol as a supplement for osteoporosis and/or osteoporotic fractures.

Comparison of the protective effects of resveratrol and pterostilbene against intestinal damage and redox imbalance in weanling piglets

BACKGROUND

Evidence indicates that early weaning predisposes piglets to intestinal oxidative stress and increases the risk of intestinal dysfunction; however, there are minimal satisfactory treatment strategies for these conditions. This study investigated the potential of resveratrol and its analog, pterostilbene, as antioxidant protectants for regulating intestinal morphology, barrier function, and redox status among weanling piglets.

METHODS

A total of 144 piglets were selected at 21 days of age and randomly allocated into one of four treatment groups, each of which included six replicates. Piglets in a sow-reared control group were suckling normally between ages 21 and 28 days, while those in weaned groups were fed a basal diet, supplemented with either 300 mg/kg of resveratrol or with 300 mg/kg of pterostilbene. Parameters associated with intestinal injury and redox status were analyzed at the end of the feeding trial.

RESULTS

Early weaning disrupted the intestinal function of young piglets, with evidence of increased diamine oxidase activity and D-lactate content in the plasma, shorter villi, an imbalance between cell proliferation and apoptosis, an impaired antioxidant defense system, and severe oxidative damage in the jejunum relative to suckling piglets. Feeding piglets with a resveratrol-supplemented diet partially increased villus height (P = 0.056) and tended to diminish apoptotic cell numbers (P = 0.084) in the jejunum compared with those fed a basal diet. Similarly, these beneficial effects were observed in the pterostilbene-fed piglets. Pterostilbene improved the feed efficiency of weanling piglets between the ages of 21 and 28 days; it also resulted in diminished plasma diamine oxidase activity and D-lactate content relative to untreated weaned piglets (P < 0.05). Notably, pterostilbene restored jejunal antioxidant capacity, an effect that was nearly absent in the resveratrol-fed piglets. Pterostilbene reduced the malondialdehyde and 8-hydroxy-2´-deoxyguanosine contents of jejunal mucosa possibly through its regulatory role in facilitating the nuclear translocation of nuclear factor erythroid-2-related factor 2 and the expression levels of NAD(P)H quinone dehydrogenase 1 and superoxide dismutase 2 (P < 0.05).

CONCLUSIONS

The results indicate that pterostilbene may be more effective than its parent compound in alleviating early weaning-induced intestinal damage and redox imbalance among young piglets.

Effects of Early Resveratrol Intervention on Skeletal Muscle Mitochondrial Function and Redox Status in Neonatal Piglets with or without Intrauterine Growth Retardation

Skeletal muscle mitochondrial malfunction of offspring induced by intrauterine growth retardation (IUGR) may be a contributor to growth restriction and metabolic disorder at various periods of life. This study explored the effects of IUGR and resveratrol (RSV) on mitochondrial function and redox status in the longissimus dorsi muscle (LM) of piglets during the sucking period. A total of 36 pairs of IUGR and normal birth weight male piglets were orally fed with either 80 mg RSV/kg body weight/d or 0.5% carboxymethylcellulose sodium during days 7-21 after birth. The results showed that RSV treatment improved anomalous mitochondrial morphology, increased adenosine triphosphate and glycogen contents, and enhanced nicotinamide adenine dinucleotide/reduced form of nicotinamide-adenine dinucleotide ratio in the LM of IUGR piglets. Moreover, the IUGR-induced increased malondialdehyde and protein carbonyl concentrations, abnormal mtDNA number, and suppressed genes expression of mitochondrial biogenesis such as nuclear respiratory factor 1, estrogen-related receptor alpha, and polymerase gamma in the LM were restored to some extent by RSV treatment. Additionally, RSV increased mitochondrial complex V activity in the LM of piglets. Collectively, RSV administration alleviated the LM mitochondrial dysfunction and oxidative damage of IUGR piglets.

Effects of dietary resveratrol supplementation in sows on antioxidative status, myofiber characteristic and meat quality of offspring

This study investigated the influence of dietary resveratrol (300 mg/kg) supplementation in sows on the antioxidative status, myofiber characteristic and meat quality of their progeny. Results showed that maternal dietary resveratrol supplementation increased (P < 0.05) the backfat thickness and tended (P = 0.055) to increase the intramuscular fat of finishing pigs. The drip loss and lactic acid level were reduced, and the pH_{24 h} of longissimus thoracis was increased by maternal dietary resveratrol supplementation (P < 0.05). Maternal dietary resveratrol supplementation increased the mRNA and protein expression of MyHC I and decreased the mRNA and protein expression of MyHC IIb in the longissimus thoracis (P < 0.05). The malonaldehyde (MDA) level in longissimus thoracis was reduced and the superoxide dismutase (SOD) activity and SOD2 mRNA expression were increased by maternal dietary resveratrol supplementation (P < 0.05). In conclusion, dietary resveratrol supplementation in sows improves the meat quality of offspring by altering the myofiber characteristic and antioxidative status.

Comparison of the effects of resveratrol and its derivative pterostilbene on hepatic oxidative stress and mitochondrial dysfunction in piglets challenged with diquat

This study investigated the potential of resveratrol (RSV) and its derivative pterostilbene (PT) to prevent diquat (DQ)-induced hepatic oxidative damage and mitochondrial dysfunction in piglets. Seventy-two weanling piglets were randomly divided into the following treatment groups: non-challenged control group, DQ-challenged control group, and DQ-challenged groups supplemented with either 300 mg RSV per kg of diet or an equivalent amount of PT. Each treatment group consisted of six replicates with three piglets per replicate (n = 6). After a two-week feeding trial, piglets were intraperitoneally injected with either 10 mg DQ per kg of body weight or sterile saline. At 24 hours post-injection, one piglet from each replicate (six piglets per treatment) was randomly selected for sample collection and biochemical analysis. Compared with the DQ-challenged control group, PT attenuated the growth loss of piglets after the DQ challenge (P < 0.05). Administration of PT was more effective than its parent compound in inhibiting the DQ-induced hepatic apoptosis and the increased generation of total cholesterol, superoxide anion, and lipid peroxidation products (P < 0.05). Specifically, PT facilitated nuclear factor erythroid 2-related factor 2 signals and the expression and activity of manganese superoxide dismutase, while it also prevented mitochondrial swelling, membrane potential collapse, and adenosine triphosphate depletion, possibly through the activation of sirtuin 1 (P < 0.05). These results indicate that PT may be superior to RSV as an antioxidant to protect the liver of young piglets from oxidative insults.

Pterostilbene as a protective antioxidant attenuates diquat-induced liver injury and oxidative stress in 21-day-old broiler chickens

This study investigated the effects of pterostilbene (PT) supplementation on growth performance, hepatic injury, and antioxidant variables in a broiler chicken model with diquat (DQ)-induced oxidative stress. There were 192 one-day-old male Ross 308 broiler chicks randomly allocated to one of two treatment groups: 1) broilers fed a basal diet and 2) broilers fed a diet supplemented with 400 mg/kg PT. At 20 D of age, half of the broilers in each group were intraperitoneally injected with DQ (20 mg per kg BW), whereas the other half were injected with an equivalent amount of sterile saline. Diquat induced a rapid loss of BW (P < 0.001) 24 h post-injection, but dietary PT supplementation improved the BW change of broilers (P = 0.014). Compared with unchallenged controls, the livers of DQ-treated broilers were in severe cellular damage and oxidative stress, with the presence of higher plasma transaminase activities (P < 0.05), a greater number of apoptotic hepatocytes (P < 0.001), and an increased malondialdehyde content (P = 0.007). Pterostilbene supplementation prevented the increases in plasma aspartate aminotransferase activity (P = 0.001), the percentage of hepatocyte apoptosis (P < 0.001), and the hepatic malondialdehyde accumulation (P = 0.011) of the DQ-treated broilers. Regarding the hepatic antioxidant function, PT significantly increased total antioxidant capacity (P = 0.007), superoxide dismutase activity (P = 0.016), reduced glutathione content (P = 0.011), and the ratio of reduced glutathione to oxidized glutathione (P = 0.003), whereas it reduced the concentration of oxidized glutathione (P = 0.017). Pterostilbene also boosted the expression levels of nuclear factor erythroid 2–related factor 2 (P = 0.010), heme oxygenase 1 (P = 0.037), superoxide dismutase 1 (P = 0.014), and the glutamate–cysteine ligase catalytic subunit (P = 0.001), irrespective of DQ challenge. In addition, PT alleviated DQ-induced adenosine triphosphate depletion (P = 0.010). In conclusion, PT attenuates DQ-induced hepatic injury and oxidative stress of broilers presumably by restoring hepatic antioxidant function.

Dietary Supplementation of L-Arginine and N-Carbamylglutamate Attenuated the Hepatic Inflammatory Response and Apoptosis in Suckling Lambs with Intrauterine Growth Retardation

L-arginine (Arg) is a semiessential amino acid with several physiological functions. N-Carbamylglutamate (NCG) can promote the synthesis of endogenous Arg in mammals. However, the roles of Arg or NCG on hepatic inflammation and apoptosis in suckling lambs suffering from intrauterine growth restriction (IUGR) are still unclear. The current work is aimed at examining the effects of dietary Arg and NCG on inflammatory and hepatocyte apoptosis in IUGR suckling lambs. On day 7 after birth, 48 newborn Hu lambs were selected from a cohort of 432 twin lambs. Normal-birthweight and IUGR Hu lambs were allocated randomly (n = 12/group) to control (CON), IUGR, IUGR+1% Arg, or IUGR+0.1% NCG groups. Lambs were fed for 21 days from 7 to 28 days old. Compared with CON lambs, relative protein 53 (P53), apoptosis antigen 1 (Fas), Bcl-2-associated X protein (Bax), caspase-3, cytochrome C, tumor necrosis factor alpha (TNF-α), nuclear factor kappa-B (NF-κB) p65, and NF-κB pp65 protein levels were higher (P < 0.05) in liver from IUGR lambs, whereas those in liver from IUGR lambs under Arg or NCG treatment were lower than those in IUGR lambs. These findings indicated that supplementing Arg or NCG reduced the contents of proinflammatory cytokines at the same time when the apoptosis-related pathway was being suppressed, thus suppressing the IUGR-induced apoptosis of hepatic cells.

Resveratrol Attenuates Oxidative Stress-Induced Intestinal Barrier Injury through PI3K/Akt-Mediated Nrf2 Signaling Pathway

Oxidative stress is implicated in a wide range of intestinal disorders and closely associated with their pathological processes. Resveratrol (RSV), a plant extract, plays a vital role in protecting various organs in vitro and in vivo. However, the benefits of RSV are controversial, and underlying mechanisms for its antioxidant effects on intestinal epithelial cells remain unclear. In this study, we evaluated the effects of RSV on oxidative stress induced by H₂O₂ in IPEC-J2 cells. We found that pretreatment with RSV significantly increased cell viability; increased expression levels of tight junction (TJ) proteins (claudin-1, occludin, and ZO-1); improved activities of superoxide dismutase-1 (SOD-1), catalase (CAT), and glutathione peroxidase (GSH-Px); and decreased intracellular reactive oxygen species (ROS) levels and apoptosis induced by H₂O₂ (P < 0.05). In addition, RSV upregulated Akt phosphorylation, Nrf2 phosphorylation, and expression levels of antioxidant genes HO-1, SOD-1, and CAT in a dose-dependent manner (P < 0.05) under oxidative stress. Knockdown of Nrf2 by short-hairpin RNA (shRNA) abrogated RSV-mediated protection against H₂O₂-induced apoptosis, RSV-induced increase of TJ protein levels, and antioxidant gene expression (SOD-1, CAT, and GSH-Px) (P < 0.05). Consistent with Nrf2 knockdown, the PI3K/Akt inhibitor LY294002 significantly suppressed RSV-induced Nrf2 phosphorylation and RSV-induced increase of TJ protein levels and antioxidant gene expression under H₂O₂ treatment (P < 0.05). Collectively, these results demonstrate that RSV can directly protect IPEC-J2 cells against oxidative stress through the PI3K/Akt-mediated Nrf2 signaling pathway, suggesting that RSV may be an effective feed additive against intestinal damage in livestock production.

Tissue-specific profiling reveals modulation of cellular and mitochondrial oxidative stress in normal- and low-birthweight piglets throughout the peri-weaning period

Weaning is known to induce important nutritional and energetic stress in piglets. Low-birthweight (LBW) piglets, now frequently observed in swine production, are more likely to be affected. The weaning period is also associated with dysfunctional immune responses, uncontrolled inflammation and oxidative stress conditions that are recognized risk factors for infections and diseases. Mounting evidence indicates that mitochondria, the main cellular sources of energy in the form of adenosine 5' triphosphate (ATP) and primary sites of reactive oxygen species production, are related to immunity, inflammation and bacterial pathogenesis. However, no information is currently available regarding the link between mitochondrial energy production and oxidative stress in weaned piglets. The objective of this study was to characterize markers of cellular and mitochondrial energy metabolism and oxidative status in both normal-birthweight (NBW) and LBW piglets throughout the peri-weaning period. To conduct the study, 30 multiparous sows were inseminated and litters were standardized to 12 piglets. All the piglets were weighted at day 1 and 120 piglets were selected and assigned to 1 of 2 experimental groups: NBW (n = 60, mean weight of 1.73 ± 0.01 kg) and LBW piglets weighing less than 1.2 kg (n = 60, 1.01 ± 0.01 kg). Then, 10 piglets from each group were selected at 14, 21 (weaning), 23, 25, 29 and 35 days of age to collect plasma and organ (liver, intestine and kidney) samples. Analysis revealed that ATP concentrations were lower in liver of piglets after weaning than during lactation (P < 0.05) thus suggesting a significant impact of weaning stress on mitochondrial energy production. Oxidative damage to DNA (8-hydroxy-2'-deoxyguanosine, 8-OHdG) and proteins (carbonyls) measured in plasma increased after weaning and this coincides with a rise in enzymatic antioxidant activity of glutathione peroxidase (GPx) and superoxide dismutase (SOD) (P < 0.05). Mitochondrial activities of both GPx and SOD are also significantly higher (P < 0.05) in kidney of piglets after weaning. Additionally, oxidative damage to macromolecules is more important in LBW piglets as measured concentrations of 8-OHdG and protein carbonyls are significantly higher (P < 0.05) in plasma and liver samples, respectively, than for NBW piglets. These results provide novel information about the nature, intensity and duration of weaning stress by revealing that weaning induces mitochondrial dysfunction and cellular oxidative stress conditions which last for at least 2 weeks and more severely impact smaller piglets.

Dietary N-carbamylglutamate and l-arginine supplementation improves intestinal energy status in intrauterine-growth-retarded suckling lambs

This study explores the roles of l-arginine (Arg) and N-carbamylglutamate (NCG) supplementation in the diet in intestine damage, energy state, as well as the associated protein kinase signaling pathways activated by AMP in intrauterine growth retarded (IUGR) suckling lambs. A total of 48 newborn Hu lambs with a normal birth weight (CON) and those with IUGR were randomly divided into four groups, CON, IUGR, IUGR + 1% Arg, and IUGR + 0.1% NCG, with 12 animals in each group. All animals were fed for 21 days, from day 7-28, following birth. Our results indicated that the IUGR suckling Hu lambs in the Arg or NCG groups were associated with reduced (P < 0.05) plasma diamine oxidase (DAO) and d-lactic acid levels compared with IUGR suckling lambs. In addition, IUGR suckling Hu lambs in the Arg or NCG group were also linked with a higher (P < 0.05) villous height : crypt depth ratio (VCR), as well as villous height in the duodenum relative to those obtained for IUGR suckling Hu lambs. Relative to IUGR suckling Hu lambs, IUGR suckling Hu lambs in the Arg or NCG groups were found to have higher (P < 0.05) ATP, ADP and TAN contents, and AEC levels, and smaller (P < 0.05) AMP : ATP ratios in the duodenum, jejunum and ileum. Moreover, IUGR suckling Hu lambs in the Arg or NCG group were also linked with higher citrate synthase, isocitrate dehydrogenase and alpha-oxoglutarate dehydrogenase complex activities in the duodenum, jejunum and ileum compared with those found for IUGR suckling Hu lambs (P < 0.05), except for the activity of isocitrate dehydrogenase in the ileum. IUGR suckling Hu lambs in the Arg or NCG group were linked with a lower ratio of pAMPKα/tAMPKα and protein expression of Sirt1 and PGC1α in the ileum relative to those of the IUGR suckling Hu lambs (P < 0.05). Taken together, these findings show that supplementation of NCG and Arg in the diet can ameliorate intestinal injury, improve energy status, motivate key enzyme activities in the tricarboxylic acid (TCA) cycle, and also inhibit the AMP-activated protein kinase signaling pathways in IUGR suckling Hu lambs.

Effects of dietary methionine supplementation on growth performance, intestinal morphology, antioxidant capacity and immune function in intra-uterine growth-retarded suckling piglets

This study investigated the effects of dietary supplementation with L -methionine (L -Met), DL -methionine (DL -Met) and calcium salt of the methionine hydroxyl analog (MHA-Ca) on growth performance, intestinal morphology, antioxidant capacity and immune function in intra-uterine growth-retarded (IUGR) suckling piglets. Six normal birthweight (NBW) female piglets and 24 same-sex IUGR piglets were selected at birth. Piglets were fed nutrient adequate basal diet supplemented with 0.08% L -alanine (NBW-CON), 0.08% L -alanine (IUGR-CON), 0.12% L -Met (IUGR-LM), 0.12% DL -Met (IUGR-DLM) and 0.16% MHA-Ca (IUGR-MHA-Ca) from 7 to 21 days of age respectively (n = 6). The results indicated that IUGR decreased average daily milk (dry matter) intake and average daily gain and increased feed conversion ratio of suckling piglets (p < 0.05). Compared with the NBW-CON piglets, IUGR also impaired villus morphology and reduced antioxidant capacity and immune homeostasis in the intestine of IUGR-CON piglets (p < 0.05). Supplementation with L -Met enhanced jejunal villus height (VH) and villus area and ileal VH of IUGR piglets compared with IUGR-CON piglets (p < 0.05). Similarly, DL -Met supplementation increased VH and the ratio of VH to crypt depth in the jejunum compared with IUGR-CON pigs (p < 0.05). Supplementation with L -Met and DL -Met (0.12%) tended to increase reduced glutathione content and reduced glutathione: oxidized glutathione ratio and decrease protein carbonyl concentration in the jejunum of piglets when compared with the IUGR-CON group (p < 0.10). However, supplementation with MHA-Ca had no effect on the intestinal redox status of IUGR piglets (p > 0.10). In conclusion, supplementation with either L -Met or DL -Met has a beneficial effect on the intestinal morphology and antioxidant capacity of IUGR suckling piglets.

Resveratrol improves intestinal barrier function, alleviates mitochondrial dysfunction and induces mitophagy in diquat challenged piglets1

This study evaluated whether resveratrol can alleviate intestinal injury and enhance the mitochondrial function and the mitophagy level in diquat induced oxidative stress of piglets.

N-Acetylcysteine protects against intrauterine growth retardation-induced intestinal injury via restoring redox status and mitochondrial function in neonatal piglets

PURPOSE

Intrauterine growth retardation (IUGR) is detrimental to the intestinal development of neonates, yet satisfactory treatment strategies remain limited. This study was, therefore, conducted using neonatal piglets as a model to investigate the potential of N-acetylcysteine (NAC) to alleviate intestinal damage caused by IUGR.

METHODS

Seven normal birth weight (NBW) and fourteen IUGR neonatal male piglets were selected and then fed a basal milk diet (NBW-CON and IUGR-CON groups) or a basal milk diet supplemented with 1.2 g NAC per kg of diet (IUGR-NAC group) from 7 to 21 days of age (n = 7). Parameters associated with the severity of intestinal injury, villus morphology and ultrastructural structure, redox status, and mitochondrial function were analyzed.

RESULTS

Compared with the NBW-CON piglets, the IUGR-CON piglets exhibited decreased villus height and greater numbers of apoptotic cells in jejunum, along with the increases in malondialdehyde and protein carbonyl concentrations and a decreased adenosine triphosphate (ATP) content. Treatment with NAC significantly increased jejunal superoxide dismutase activity, reduced glutathione: oxidized glutathione ratio, and the mRNA abundance of nuclear respiratory factor 2, heme oxygenase 1, and superoxide dismutase 2 in the IUGR-NAC piglets compared with the IUGR-CON piglets. In addition, NAC improved the efficiency of mitochondrial oxidative metabolism and ATP generation, ameliorated mitochondrial swelling, and inhibited the overproduction of mitochondrial superoxide anion in the jejunal mucosa.

CONCLUSIONS

Dietary supplementation of NAC shows promise for attenuating the early intestinal injury of young piglets with IUGR, probably through its antioxidant action to restore redox status and mitochondrial function.

l-Threonine improves intestinal mucin synthesis and immune function of intrauterine growth-retarded weanling piglets

OBJECTIVES

The aim of this study was to investigate the effects of dietary l-threonine supplementation on the growth performance, intestinal immune function, mucin synthesis, and goblet cell differentiation in weanling piglets with intrauterine growth retardation (IUGR).

METHODS

Eighteen litters of newborn piglets were selected at birth, with one normal birthweight (NBW) and two IUGR piglets in each litter. At weaning, the NBW piglet and one of the IUGR piglets were assigned to groups fed a basal diet (i.e., the NBW-CON and IUGR-CON groups). The other IUGR piglet was assigned to a group fed the basal diet supplemented with 2 g l-threonine per kg of diet (i.e., IUGR-Thr group). Therefore, all piglets were distributed across three groups for a 3-wk feeding trial.

RESULTS

Compared with NBW, IUGR decreased growth performance, increased ileal proinflammatory cytokine levels, and reduced ileal mucin 2 (Muc2) content and goblet cell density of weanling piglets. Supplementation of l-threonine increased the feed efficiency of the IUGR-Thr group compared with the IUGR-CON group. The l-threonine-supplemented diet attenuated ileal inflammatory responses of the IUGR-Thr piglets and increased production of Muc2 and secretory immunoglobulin A and density of goblet cells. In addition, _L-threonine supplementation downregulated δ-like 1 and hes family bHLH transcription factor 1, whereas growth factor independence 1 and Kruppel-like factor 4 expression levels were upregulated.

CONCLUSION

Dietary l-threonine supplementation attenuates inflammatory responses, facilitates Muc2 synthesis, and promotes goblet cell differentiation in the ileum of IUGR piglets.

Transcriptome Analyses Reveal Adult Metabolic Syndrome With Intrauterine Growth Restriction in Pig Models

Epidemiological data have indicated that intrauterine growth retardation (IUGR) is a risk factor for the adult metabolic syndrome in pigs. However, the causative genetic mechanism leading to the phenotype in adulthood has not been well characterized. In the present study, both normal and IUGR adult pigs were used as models to survey the differences in global gene expression in livers through transcriptome sequencing. The transcriptome libraries generated 104.54 gb of data. In normal and IUGR pigs, 16,948 and 17,078 genes were expressed, respectively. A total of 1,322 differentially expressed genes (DEGs) were identified. Enrichment analysis of the DEGs revealed that the top overrepresented gene ontology (GO) terms and pathways were related to oxidoreductase activity, ATPase activity, amino catabolic process, glucose metabolism, and insulin signaling pathway. The increased gluconeogenesis (GNG) and decreased glycogen synthesis in the liver contributed to the glucose intolerance observed in IUGR. The reduced expression of insulin signaling genes (such as PI3K and AKT) indicated an elevated risk of diabetes in adulthood. Together, these findings provide a comprehensive understanding of the molecular mechanisms of adult IUGR pigs and valuable information for future studies of therapeutic intervention in IUGR metabolic syndrome.

Effects of dietary Bacillus amyloliquefaciens supplementation on growth performance, intestinal morphology, inflammatory response, and microbiota of intra-uterine growth retarded weanling piglets

BACKGROUND

The focus of recent research has been directed toward the probiotic potential of Bacillus amyloliquefaciens (BA) on the gut health of animals. However, little is known about BA's effects on piglets with intra-uterine growth retardation (IUGR). Therefore, this study investigated the effects of BA supplementation on the growth performance, intestinal morphology, inflammatory response, and microbiota of IUGR piglets.

METHODS

Eighteen litters of newborn piglets were selected at birth, with one normal birth weight (NBW) and two IUGR piglets in each litter (i.e., 18 NBW and 36 IUGR piglets in total). At weaning, the NBW piglet and one of the IUGR piglets were assigned to groups fed a control diet (i.e., the NBW-CON and IUGR-CON groups). The other IUGR piglet was assigned to a group fed the control diet supplemented with 2.0 g BA per kg of diet (i.e., IUGR-BA group). The piglets were thus distributed across three groups for a four-week period.

RESULTS

IUGR reduced the growth performance of the IUGR-CON piglets compared with the NBW-CON piglets. It was also associated with decreased villus sizes, increased apoptosis rates, reduced goblet cell numbers, and an imbalance between pro- and anti-inflammatory cytokines in the small intestine. Supplementation with BA improved the average daily weight gain and the feed efficiency of the IUGR-BA group compared with the IUGR-CON group (P < 0.05). The IUGR-BA group exhibited increases in the ratio of jejunal villus height to crypt depth, in ileal villus height, and in ileal goblet cell density. They also exhibited decreases in the numbers of jejunal and ileal apoptotic cells and ileal proliferative cells (P < 0.05). Supplementation with BA increased interleukin 10 content, but it decreased tumor necrosis factor alpha level in the small intestines of the IUGR-BA piglets (P < 0.05). Furthermore, compared with the IUGR-CON piglets, the IUGR-BA piglets had less Escherichia coli in their jejunal digesta, but more Lactobacillus and Bifidobacterium in their ileal digesta (P < 0.05).

CONCLUSIONS

Dietary supplementation with BA improves morphology, decreases inflammatory response, and regulates microbiota in the small intestines of IUGR piglets, which may contribute to improved growth performance during early life.