In brief: Long-term culture of spermatogonia from large animals including pigs remains challenging. This study shows that Sertoli cells, but not testicular endothelial cells, contribute to optimized culture of porcine spermatogonia (>100 days). Abstract: Spermatogonial stem cells (SSCs) are able to self-renew and differentiate into mature sperm, therefore affording life-long male fertility. SSCs are rare in testes and we previously established a culture system that enabled in vitro propagation of porcine spermatogonia (including SSCs) for up to 2 months. Testicular endothelial cells (TECs), as a key component of the germline niche, have been reported to support long-term in vitro expansion of SSCs from rodents and humans. To further optimize the porcine SSC culture, here we systematically assessed the ability of porcine TECs and Sertoli cells (SCs) as feeder layers to sustain porcine spermatogonial proliferation in vitro. We found that under the optimized condition, SCs significantly promoted the formation of typical grape-like colonies derived from SSEA4+ spermatogonia, with stable expansion for >100 days and expression of stem and germ cell markers. The cultured cells also retained normal karyotype and successfully colonized busulfan-treated mouse testes after xenotransplantation. In contrast, TECs only supported short-term spermatogonial proliferation (<60 days), and the co-cultured spermatogonia exhibited loose aggregation and salient apoptosis. Secretomic analysis further revealed that SCs were enriched with adhesion molecules, anti-stress proteins, and self-renewal-associated factors, whereas TECs preferentially secreted differentiation-, extracellular matrix remodeling-, and metabolism-related proteins. Collectively, this study demonstrates that SCs, rather than TECs, contribute to optimized culture of spermatogonia in pigs, and our SC-based optimized culture system for porcine spermatogonia provides a scalable platform for genetic manipulation of porcine SSCs, therefore facilitating their application to breeding and germplasm innovation.

This study investigated the function of epididymal extracellular vesicles (EVs) in overcoming sperm post-testicular modification deficiencies. Although EVs derived from the epididymis play a crucial role in intercellular communication and molecular exchange, there is limited research addressing how EVs released by in vitro cultured epididymal epithelial cells affect sperm function. Pig epididymal caput epithelial cells (pEECs) were successfully established and verified through immunofluorescence, Western blotting, semiquantitative analyses, and RNA sequencing. EVs from pEECs were isolated by low-temperature ultracentrifugation and characterized using NanoSight and scanning electron microscopy. Proteomic sequencing showed that these EVs are enriched in cargoes beneficial to sperm, including antioxidants, motility modulators, sperm-egg recognition molecules, and proteins associated with antigen processing and presentation. To validate their function, sperm were incubated with EVs at 17 degrees C, demonstrating that EVs could attach to sperm, enhance antioxidant capacity and motility, and reduce plasma membrane oxidation, mitochondrial impairment, and DNA damage. These findings indicate that pEECs can sustainably secrete multifunctional EVs in vitro and that these EVs confer protective effects on sperm in a time-dependent manner.

Previous studies have revealed the expression of anti-complement factors on the surface of sperm across various species to resist attacks from complement components in reproductive tracts. Here we show that the anti-complement factor The caput of the porcine epididymis specifically expresses C4BPA, which is then transported to the surface of sperm via epididymosomes. The presence of C4BPA in epididymosomes depends on its palmitoylation modification, specifically at the Cys13 and Cys23 residues. ZDHHC8 has been pinpointed as the palmitoyl transferase that carries out this modification. Palmitoylated C4BPA in epididymosomes significantly resists attacks by complement C4 on sperm, maintaining porcine sperm motility. Our findings reveal a critical role for palmitoylated C4BPA in mitigating C4-mediated damage to sperm, highlighting its physiological relevance in preserving sperm motility and viability.

Seasonal breeding is an important adaptive strategy for animals. Recent studies have highlighted the potential role of the gut microbiota in reproductive health. However, the relationship between the gut microbiota and reproduction in seasonal breeders remains unclear. In this study, we selected a unique single food source animal, the flying squirrel (Trogopterus xanthipes), as a model organism for studying seasonal breeding. By integrating transcriptomic, metabolomic, and microbiome data, we comprehensively investigated the regulation of the gut-metabolism-testis axis in seasonal breeding. Here, we demonstrated a significant spermatogenic phenotype and highly active spermatogenic transcriptional characteristics in the testes of flying squirrels during the breeding season, which were associated with increased polyamine metabolism, primarily involving spermine and gamma-amino butyric acid. Moreover, an enrichment of Ruminococcus was observed in the large intestine during the breeding season and may contribute to enhanced methionine biosynthesis in the gut. Similar changes in Ruminococcus abundance were also observed in several other seasonal breeders. These findings innovatively revealed that reshaping the gut microbiota regulates spermatogenesis in seasonal breeders through polyamine metabolism, highlighting the great potential of the gut-testis axis in livestock animal breeding and human health management.

Chronic stress adversely affects reproductive health, increasing susceptibility to pathologies such as orchitis. Additionally, the maintenance of iron homeostasis is essential for preserving the function of the testicles, and iron overload leads to lipid peroxidation and iron accumulation, which induces testicular cell ferroptosis. Ursolic acid (UA), a pentacyclic triterpenoid compound naturally occurring in various plants, exhibits therapeutic potential as an agent for inflammatory and chronic degenerative diseases. However, its involvement in orchitis and ferroptosis remains unclear. The aim of this research was to elucidate the impact of UA on ferroptosis in testicular inflammation. The histopathological data revealed inflammatory infiltration in the testicular tissues from accidently deceased adult forest musk deer (FMD) under chronic stress. In vitro, UA effectively attenuated tumor necrosis factor-alpha (TNF-alpha)-induced inflammation. Additionally, UA suppressed ferroptosis through the regulation of the breakdown of excessive lipid peroxides, enhancement in the activity of antioxidant enzymes, and activation of intracellular iron metabolism. Taken together, the current study elucidates multi-target and multi-pathway therapeutic effects of UA on reproductive homeostasis. These findings highlight that UA may serve as a potential functional component in the prevention of chronic stress-induced diseases.

Selenium nanoparticles (SeNPs) were often used as growth and antioxidant capacity promoter. In this study, we found selenium nanoparticles (SeNPs) could improve the survival rate of Onychostoma macrolepis (O. macrolepis) fry as a feed additive after a challenged by Aeromonas hydrophila (A. hydrophila). To further explore the mechanism of SeNPs against bacterial infection, we examined the changes before and after bacterial infection, and the results showed that large amounts of peroxide were produced under A. hydrophila infection in O. macrolepis fry, and then the excessive accumulation of peroxides led to a large amount of ferroptosis in the liver. Interestingly, we found supplementing 0.9 mg/kg biogenic SeNPs decreased MDA, iron content, and enhanced T-AOC levels in the liver of O. macrolepis fry after a challenged by Aeromonas hydrophila (P˂0.01). Especially, the diet with 0.9 mg/kg biogenic SeNPs could significantly increase the expression level of Glutathione peroxidase-4 (GPX4), nuclear factor erythroid2-related factor 2 (Nrf2), and Ferroportin 1 (FPN1) in the liver of O. macrolepis after infection with A. hydrophila. In summary, the results of this research suggested that the diet with 0.9 mg/kg biogenic SeNPs was an optimal additive dose to improve the survival rate of O. macrolepis fry by increasing antioxidant capacity and inhibiting ferroptosis, which sheds a new light on the mechanism of antibacterial infection in fish from the perspective of ferroptosis.

Busulfan, an indispensable medicine in cancer treatment, can cause serious reproductive system damage to males as a side effect of its otherwise excellent therapeutic results. Its widespread use has also caused its accumulation in the environment and subsequent ecotoxicology effects. As a Chinese medicine, Wulingzhi (WLZ) has the effects of promoting blood circulation and improving female reproductive function. However, the potential effects of WLZ in male reproduction and in counteracting busulfan-induced testis damage, as well as its probable mechanisms, are still ambiguous. In this study, busulfan was introduced in a mouse model to evaluate its production of the testicular damage. The components of different WLZ extracts were compared using an untargeted metabolome to select extracts with greater efficacy, which were further confirmed in vivo. Here, we demonstrate abnormal spermatogenesis and low sperm quality in busulfan-injured testes. The WLZ extracts showed a strong potential to rehabilitate the male reproductive system; this effect was more prominent in room-temperature extracts. Additionally, both water and ethanol WLZ extracts at room temperature alleviated various busulfan-induced adverse effects. In particular, WLZ recovered spermatogenesis, re-activated arginine biosynthesis, and alleviated the increased oxidative stress and inflammation in the testis, ultimately reversing the busulfan-induced testicular injury. Collectively, these results suggest a promising approach to protecting the male reproductive system from busulfan-induced adverse side effects, as well as those of other similar anti-cancer drugs.

RNA editing is increasingly recognized as a post-transcriptional modification that directly affects viral infection by regulating RNA stability and recoding proteins. the duck hepatitis A virus genotype 3 (DHAV-3) infection is seriously detrimental to the Asian duck industry. However, the landscape and roles of RNA editing in the susceptibility and resistance of Pekin ducks to DHAV-3 remain unclear. Here, we profiled dynamic RNA editing events in liver tissue and investigated their potential functions during DHAV-3 infection in Pekin ducks. We identified 11,067 informative RNA editing sites in liver tissue from DHAV-3-susceptible and -resistant ducklings at three time points during virus infection. Differential RNA editing sites (DRESs) between S and R ducks were dynamically changed during infection, which were enriched in genes associated with vesicle-mediated transport and immune-related pathways. Moreover, we predicted and experimentally verified that RNA editing events in 3′-UTR could result in loss or gain of miRNA–mRNA interactions, thereby changing the expression of target genes. We also found a few DRESs in coding sequences (CDSs) that altered the amino acid sequences of several proteins that were vital for viral infection. Taken together, these data suggest that dynamic RNA editing has significant potential to tune physiological processes in response to virus infection in Pekin ducks, thus contributing to host differential susceptibility to DHAV-3.

Glutathione peroxisomal-5 (Gpx5) promotes the elimination of H2O2 or organic hydrogen peroxide, and plays an important role in the physiological process of resistance to oxidative stress (OS). To directly and better understand the protection of Gpx5 against OS in epididymal cells and sperm, we studied its mechanism of antioxidant protection from multiple aspects. To more directly investigate the role of Gpx5 in combating oxidative damage, we started with epididymal tissue morphology and Gpx5 expression profiles in combination with the mouse epididymal epithelial cell line PC1 (proximal caput 1) expressing recombinant Gpx5. The Gpx5 is highly expressed in adult male epididymal caput, and its protein signal can be detected in the sperm of the whole epididymis. Gpx5 has been shown to alleviate OS damage induced by 3-Nitropropionic Acid (3-NPA), including enhancing antioxidant activity, reducing mitochondrial damage, and suppressing cell apoptosis. Gpx5 reduces OS damage in PC1 and maintains the well-functioning extracellular vesicles (EVs) secreted by PC1, and the additional epididymal EVs play a role in the response of sperm to OS damage, including reducing plasma membrane oxidation and death, and increasing sperm motility and sperm-egg binding ability. Our study suggests that GPX5 plays an important role as an antioxidant in the antioxidant processes of epididymal cells and sperm, including plasma membrane oxidation, mitochondrial oxidation, apoptosis, sperm motility, and sperm-egg binding ability.

The epididymis and epididymosomes are crucial for regulating sperm motility, a key factor in male fertility. Palmitoylation, a lipid modification involving the attachment of palmitic acid to cysteine residues, is essential for protein function and localization. Additionally, this modification plays a vital role in the sorting of proteins into exosomes. This study investigates the role of S-palmitoylation at the Cys15 residue of the C4b binding protein alpha chain (C4BPA) in murine sperm motility. Our findings revealed high expression of C4BPA mRNA in the caput epididymis, with the protein present across all regions of the epididymis. Palmitoylation of C4BPA in epididymal epithelial cells was essential for its enrichment in epididymosomes and on sperm, thereby maintaining sperm motility. Inhibition of palmitoylation significantly reduced sperm motility and the localization of C4BPA on sperm. Additionally, palmitoylated C4BPA in exosomes resisted complement C4 attacks, preserving motility, unlike mutated C4BPA (C15S). These results highlight the critical role of palmitoylated C4BPA in protecting sperm from complement attacks and maintaining motility, suggesting that reversible palmitoylation of epididymal proteins could be explored as a therapeutic strategy for male contraception. Our study underscores the importance of post-translational modifications in sperm function and presents new insights into potential male contraceptive methods.

2-Bromopalmitate (2-BP) is a palmitoylation inhibitor that can prevent the binding of palmitic acid to proteins, thereby exhibiting significant effects in promoting inflammation and regulating the immune system. However, limited research has been conducted regarding the direct effects of 2-BP on the animal organism. Therefore, we probed mice injected with 2-BP for altered expression of inflammatory genes, with a focus on demonstrating changes in the intestinal flora as well as damage to the reproductive system. Our findings indicate that 2-BP can induce substantial inflammatory responses in visceral organs and cause testicular dysfunction. The key changes in the gut microbiota were characterized by an abundance of Firmicutes, Clostridiales, Rikenellaceae_RC9_gut_group, Desulfovibrio, Muribaculaceae, and Alistipes, and their metabolism has been intricately linked to visceral inflammation. Overall, the findings of this study provide a sound scientific basis for understanding the impact of high doses of 2-BP in mammals, while also offering crucial support for the development of preclinical models to suppress palmitoylation.

The Onychostoma macrolepis have a unique survival strategy, overwintering in caves and returning to the river for reproduction in summer. The current knowledge on the developmental status of its testes during winter and summer is still undiscovered. We performed RNA-seq analysis on O. macrolepis testes between January and June, using the published genome (NCBI, ASM1243209v1). Through KEGG and GO enrichment analysis, we were able to identify 2111 differentially expressed genes (DEGs) and demonstrate their functions in signaling networks associated with the development of organism. At the genomic level, we found that during the overwintering phase, genes associated with cell proliferation (ccnb1, spag5, hdac7) were downregulated while genes linked to testicular fat metabolism (slc27a2, scd, pltp) were upregulated. This indicates suppression of both mitosis and meiosis, thereby inhibiting energy expenditure through genetic regulation of testicular degeneration. Furthermore, in January, we observed the regulation of autophagy and apoptosis (becn1, casp13), which may have the function of protecting reproductive organs and ensuring their maturity for the breeding season. The results provide a basis for the development of specialized feed formulations to regulate the expression of specific genes, or editing of genes during the fish egg stage, to ensure that the testes of O. macrolepis can mature more efficiently after overwintering, thereby enhancing reproductive performance.

BACKGROUND:Endothelial cell (EC) metabolism plays a crucial role in the process of angiogenesis. Intrinsic metabolic events such as glycolysis, fatty acid oxidation, and glutamine metabolism, support secure vascular migration and proliferation, energy and biomass production, as well as redox homeostasis maintenance during vessel formation. Nevertheless, perturbation of EC metabolism instigates vascular dysregulation-associated diseases, especially cancer. AIM OF REVIEW:In this review, we aim to discuss the metabolic regulation of angiogenesis by EC metabolites and metabolic enzymes, as well as prospect the possible therapeutic opportunities and strategies targeting EC metabolism. KEY SCIENTIFIC CONCEPTS OF REVIEW:In this work, we discuss various aspects of EC metabolism considering normal and diseased vasculature. Of relevance, we highlight that the implications of EC metabolism-targeted intervention (chiefly by metabolic enzymes or metabolites) could be harnessed in orchestrating a spectrum of pathological angiogenesis-associated diseases.

BACKGROUND/OBJECTIVE:The effects of fathers' high-fat diet (HFD) on the reproductive health of their male offspring (HFD- F1) remain to be elucidated. Parental obesity is known to have a negative effect on offspring fertility, but there are few relevant studies on the effects of HFD-F1 on reproductive function. METHODS:We first succeeded in establishing the HFD model, which provides a scientific basis in the analysis of HFD-F1 reproductive health. Next, we assessed biometric indices, intratesticular cellular status, seminiferous tubules and testicular transcriptomic homeostasis in HFD-F1. Finally, we examined epididymal (sperm-containing) apoptosis, as well as antioxidant properties, motility, plasma membrane oxidation, DNA damage, and sperm-egg binding in the epididymal sperm. RESULTS:Our initial results showed that HFD-F1 mice had characteristics similar to individuals with obesity, including higher body weight and altered organ size. Despite no major changes in the types of testicular cells, we found decreased activity of important genes and noticed the presence of abnormally shaped sperm at seminiferous tubule lumen. Further analysis of HFD-F1 testes suggests that these changes might be caused by increased vulnerability to oxidative stress. Finally, we measured several sperm parameters, these results presented HFD-F1 offspring exhibited a deficiency in antioxidant properties, resulting in damaged sperm mitochondrial membrane potential, insufficient ATP content, increased DNA fragmentation, heightened plasma membrane oxidation, apoptosis-prone and decreased capacity for sperm-oocyte binding during fertilization. CONCLUSION:HFD- F1 subfertility arises from the susceptibility of the transcriptional network to oxidative stress, resulting in reduced antioxidant properties, motility, sperm-egg binding, and elevated DNA damage. Schematic representation of the HFD-F1 oxidative stress susceptibility to subfertility. Notably, excessive accumulation of ROS surpasses the physiological threshold, thereby damaging PUFAs within the sperm plasma membrane. This oxidative assault affects crucial components such as mitochondria and DNA. Consequently, the sperm's antioxidant defense mechanisms become compromised, leading to a decline in vitality, motility, and fertility.

The production of selenium-enriched fish can contribute to alleviating selenium deficiency in human diets. However, it is still unclear which selenium source, as an additive, can efficiently and cost-effectively produce high-quality selenium-enriched fish. This study evaluated the effects of selenium nanoparticles (SeNP), selenite, and selenomethionine (SeMet) on the growth, antioxidant capacity, selenium content, selenium speciation, and meat quality of grass carp. Ten diets were prepared, including a basal diet (BD) and three concentrations (0.1, 0.3, and 0.9 mg/kg) of SeNP, selenite, and SeMet. A total of 600 fish (250.79 ± 1.57 g) were randomly assigned to 30 tanks (3 tanks/group). Fish were fed the experimental diet three times daily for 60 d. In this study, SeNP most significantly promoted the growth and antioxidant capacity of grass carp, with 0.3 mg/kg SeNP identified as the optimal additive concentration. Additionally, SeNP demonstrated equally excellent bioavailability as SeMet and significantly increased the content of SeMet in grass carp (Ctenopharyngodon idella) muscle. Furthermore, compared to SeMet and selenite, dietary SeNP could more significantly enhance the content of selenocysteine (SeCys2) and methylselenocysteine (MeSeCys) in grass carp muscle tissue. In addition, we have demonstrated that SeCys2 and MeSeCys promote apoptosis of cancer cells (Hela) through the mitochondrial apoptotic pathway (involving Bax and Bcl-2). Furthermore, as an additive, 0.3 mg/kg SeNP significantly improved the flesh quality of grass carp by reducing crude fat and heavy metal content, as well as increasing the levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and the ratio of n-3/n-6 polyunsaturated fatty acid (PUFA). In summary, SeNP is the most suitable additive for producing selenium-enriched fish.

BACKGROUND:Abnormal placental angiogenesis is an important cause of fetal intrauterine growth restriction (IUGR), but its underlying mechanisms and therapies remain unclear. Adenosine and its mediated signaling has been reported to be associated with the development of angiogenesis. However, whether the adenosine-related signaling plays a role in modulating angiogenesis in placenta and the IUGR pregnancy outcomes remains unclear.METHODS:The angiogenesis and adenosine signaling expressions in normal and IUGR placentas were detected in different species. And the role of adenosine in regulating IUGR pregnancy outcomes was evaluated using diet-induced IUGR mouse model. Molecular mechanisms underlying adenosine-induced angiogenesis were investigated by in vitro angiogenesis assays and in vivo Matrigel plug assays.RESULTS:Here, we demonstrated poor angiogenesis and low adenosine concentration and downregulated expression of its receptor A2a (ADORA2A [adenosine A2a receptor]) in IUGR placenta. Additionally, the beneficial effects of adenosine in improving IUGR pregnancy outcomes were revealed in a diet-induced IUGR mouse model. Moreover, adenosine was found to effectively improve adenosine signaling and angiogenesis in IUGR mice placenta. Mechanistically, by using angiogenesis assays in vitro and in vivo, adenosine was shown to activate ADORA2A to promote the phosphorylation of Stat3 (signal transducer and activator of transcription 3) and Akt (protein kinase B), resulting in increased Ang (angiogenin)-dependent angiogenesis.CONCLUSIONS:Collectively, this study uncovers an unexpected mechanism of promoting placental angiogenesis by adenosine-ADORA2A signaling and advances the translation of this signaling as a prognostic indicator and therapeutic target in IUGR treatment.

Abnormal placental angiogenesis is associated with the occurrence of intrauterine growth restriction (IUGR) in piglets, and effective treatment strategies against this occurrence remain to be explored. Adenosine has been reported to play an important role in angiogenesis, but its role in placental angiogenesis is still unknown. Here, we investigated the effect of dietary adenosine supplementation on IUGR occurrence in piglets by analyzing the role of adenosine in placental angiogenesis for Normal and IUGR piglets. Specifically, 88 sows were allotted to 2 treatments (n = 44) and fed a basal diet supplemented with 0% or 0.1% of adenosine from day 65 of gestation until farrowing, followed by collecting the placental samples of Normal and IUGR piglets, and recording their characteristics. The results showed that adenosine supplementation increased the mean birth weight of piglets (P < 0.05) and placental efficiency (P < 0.05), while decreasing the IUGR piglet rate (P < 0.05). Expectedly, the placenta for IUGR neonates showed a down-regulated vascular density (P < 0.05) and angiogenesis as evidenced by the expression level of vascular cell adhesion molecule-1 (VCAM1) (P < 0.05). Notably, dietary adenosine supplementation promoted angiogenesis (P < 0.05) both in the Normal and IUGR placenta. More importantly, the expression level of adenosine A2a receptor (ADORA2A) was lower (P < 0.05) in the IUGR placenta than in Normal placenta, whereas adenosine treatment could significantly increase ADORA2A expression, and also had an interaction effect between factors IUGR and Ado. Collectively, placentae for IUGR piglets showed impaired angiogenesis and down-regulated expression level of ADORA2A, while dietary adenosine supplementation could activate ADORA2A expression, improve the placental angiogenesis, and ultimately decrease the occurrence of IUGR in piglets.

Background Oxidative stress in placenta is associated with the occurrence of adverse pregnancy outcomes in sow, but there are few satisfactory treatment strategies for these conditions. This study investigated the potential of cysteamine (CS) as an antioxidant protectant for regulating the reproductive performance, redox status, and placental angiogenesis of sows. Methods The placental oxidative stress status and vascular density of piglets with different birth weights: < 1.0 kg (low birth weight, LBW) and 1.4–1.6 kg (normal birth weight, NBW) were evaluated, followed by allotting 84 sows to four treatments ( n = 21) and feeding them with a basal diet supplemented with 0, 100, 300, or 500 mg/kg of CS from d 85 of gestation to d 21 of lactation, respectively. Placenta, serum, and colostrum samples of sows or piglets were collected, and the characteristics of sows and piglets were recorded. Furthermore, the in vivo results were validated using porcine vascular endothelial cells (PVECs). Results Compared with the NBW placentae, the LBW placentae showed increased oxidative damage and were vulnerable to angiogenesis impairment. Particularly, H 2 O 2 -induced oxidative stress prompted intracellular reactive oxygen species generation and inhibited the tube formation and migration of PVECs as well as the expression of vascular endothelial growth factor-A (VEGF-A) in vitro . However, dietary CS supplementation can alleviate oxidative stress and improve the reproductive performance of sows. Specifically, compared with the control group, dietary 100 mg/kg CS could (1) decrease the stillbirth and invalid rates, and increase both the piglet birth weight in the low yield sows and the placental efficiency; (2) increase glutathione and reduce malondialdehyde in both the serum and the colostrum of sows; (3) increase the levels of total antioxidant capacity and glutathione in LBW placentae; (4) increase the vascular density, the mRNA level of VEGF-A , and the immune-staining intensity of platelet endothelial cell adhesion molecule-1 in the LBW placentae. Furthermore, the in vitro experiment indicated that CS pre-treatment could significantly reverse the NADPH oxidase 2-ROS-mediated inactivation of signal transducer and activator of transcription-3 (Stat3) signaling pathway induced by H 2 O 2 inhibition of the proliferation, tube formation, and migration of PVECs. Meanwhile, inhibition of Stat3 significantly decreased the cell viability, tube formation and the VEGF-A protein level in CS pretreated with H 2 O 2 -cultured PVECs. Conclusions The results indicated that oxidative stress and impaired angiogenesis might contribute to the occurrence of LBW piglets during pregnancy, but CS supplementation at 100 mg/kg during late gestation and lactation of sows could alleviate oxidative stress and enhance angiogenesis in placenta, thereby increasing birth weight in low yield sows and reducing stillbirth rate. The in vitro data showed that the underlying mechanism for the positive effects of CS might be related to the activation of Stat3 in PVECs.

Lay Summary Placental angiogenesis regulates piglet growth and development. Adenosine 5MODIFIER LETTER PRIME-monophosphate (AMP), a breakdown product of adenosine triphosphate, can be further converted to adenosine with various biological activities. However, little is known about whether AMP supplementation favors piglet growth and development as well as placental angiogenesis. This study facilitates the understanding of the promoting effects of AMP supplementation on placental angiogenesis and farrowing performance. Our previous study found that dietary nucleotide supplementation, including adenosine 5MODIFIER LETTER PRIME-monophosphate (AMP), could increase AMP content in sow milk and promote piglet growth, but its effects on placental efficiency and piglet vitality remain unknown. This experiment aimed to investigate the effects of dietary AMP or its metabolite adenosine (ADO) supplementation on sow reproductive performance and placental angiogenesis. A total of 135 sows with a similar farrowing time were blocked by backfat and body weight (BW) at day 65 of gestation and assigned to one of three dietary treatment groups (n = 45 per treatment): basal diet, basal diet supplemented with 0.1% AMP or 0.1% ADO, respectively. Placental analysis and the characteristics of sows and piglets unveiled that compared with control (CON) group, AMP or ADO supplementation could improve sow placental efficiency (P < 0.05) and newborn piglet vitality (P < 0.05), increase piglet birth weight (P < 0.05), and reduce stillbirth rate (P < 0.05). More importantly, AMP or ADO supplementation could increase the contents of AMP, ADO, and their metabolites in placentae (P < 0.05). Meanwhile, AMP or ADO supplementation could also increase placental vascular density (P < 0.05) and the expression of vascular endothelial growth factor A (P < 0.05), as well as promote the migration and tube formation of porcine iliac artery endothelial cells (P < 0.05). Overall, maternal dietary AMP or ADO supplementation could increase their contents in the placenta, thereby improving placental angiogenesis and neonatal piglet vitality. The present findings may offer insights into new strategies for regulating sow reproductive performance and piglet growth, highlighting the potential application of AMP in sow production.

Background: Dietary nucleotides [inclusion adenosine 5'-monophosphate (AMP)] supplementation was shown to promote the feed intake of sows and increase the AMP content in their milk in our previous work, but whether AMP shapes the energy expenditure and lipid metabolism in mammals remains unknown. Here, we aimed to explore the effects and the related mechanism of dietary AMP supplementation on food intake, body composition, energy expenditure, and lipid metabolism in male mice. Methods: 4-week-old C57BL/6 mice (After a 1-wk adaptation) were fed with basal diet and basal diet supplemented with 0.1% AMP, respectively. Animal food intake and body weight were monitored and after 4 weeks all animals were sacrificed to measure the body composition, energy expenditure and lipid metabolism changes. Results: Compared with the control, the 0.1% AMP fed mice showed higher food intake while lower adipose weight. Intriguingly, dietary AMP supplementation was found to stimulate brown adipose tissue thermogenesis as evidenced by the increase in the uncoupling protein-1 level and the core temperature. Moreover, AMP supplementation was shown to promote white adipose tissue lipolysis as indicated by smaller lipid droplet size in mice. These results demonstrate that dietary AMP supplementation could enhance oxygen consumption and energy expenditure. Conclusions: This study highlights the physiological importance of AMP supplementation in mediating food intake and energy expenditure and suggests its potential as an adjuvant therapy in preventing energy metabolic disorders (mainly obesity and diabetes).