Keel bone fracture (KBF) is a common injury that affects the behaviour and welfare of laying hens. This study aimed to investigate the impact of KBF on anxiety-like behaviour in laying hens and explore the underlying regulatory mechanisms. Ninety 46-week-old Hy-Line Brown hens were individually housed in furnished cages and divided into two groups based on keel bone diagnosis: the non-fracture group (NF) and the KBF group. Keel bone status was evaluated at 46, 49, and 52 weeks of age using a combination of palpation and X-ray examination. Behavioural data were collected two days after each diagnosis. The open field test (OFT) was conducted at 49 weeks (n = 25 per group), and the attention bias test (ABT) was performed at 52 weeks (NF = 39, KBF=51). Behavioural observations revealed that hens with KBF displayed significantly increased preening and toe pecking behaviours. OFT showed a significant prolongation of the first movement latency and a reduction in exploration time in KBF hens. KBF hens exhibited significantly longer latencies for the first vocalization, first step, and first eating in ABT. Collectively, the OFT and ABT results indicated that hens with keel bone fractures exhibited the anxiety-like behaviour.Physiological indicators (n = 6) revealed elevated serum corticosterone levels and decreased serum serotonin levels in hens with KBF, suggesting that KBF induces a stress response, which contributes to the manifestation of anxiety-like behaviours. Golgi staining (n = 3) revealed a significant reduction in hippocampal neuronal complexity in KBF hens, indicating neuronal damage. qRT-PCR (n = 6) and western blot (n = 3) analysis demonstrated altered expression of genes related to anxiety in the hippocampus, characterized by a notable decrease in the protein levels of DCX, BDNF, and EGR1, suggesting impaired neurogenesis (DCX), reduced stress resilience (DCX and BDNF), and decrease neuroplasticity (BDNF and EGR1), all of which are closely linked to anxiety-like behaviour.Therefore, we suggest that keel bone fracture is associated with anxiety-like behaviour in laying hens, which may result from stress signals generated by the fracture that trigger the expression of anxiety-related genes in the brain.

Multiple stressors represent a major threat to animal welfare and productivity by triggering physiological and behavioral abnormalities. This study investigated whether dietary resveratrol (RES) mitigates the adverse effects of multiple stressors, on behavior, hypothalamic injury, intestinal barrier integrity, gut microbiota, and the microbial-gut-brain (MGB) axis in layer pullets, modeled by chronic unpredictable mild stress (CUMS). The experiment consisted of two phases. In Phase 1,300 one-day-old chicks were randomly assigned to control (CON) and CUMS groups. In Phase 2,480 chicks were allotted to five groups: CON, CUMS, and CUMS supplemented with 200, 400, or 800 mg kg−1 RES (L-RES, M-RES, H-RES). After a 1-wk acclimation period, all groups except CON were exposed to a 5-wk CUMS protocol, while RES treatments were simultaneously administered for the same duration. CUMS exposure induced depression-like behaviors, dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, and significant reductions in key neurotransmitters (serotonin and dopamine) and brain-derived neurotrophic factor (BDNF), collectively reflecting neuroinflammation and impaired neuroplasticity. Intestinal barrier integrity was also disrupted, as evidenced by the downregulation of tight junction proteins, while colonic inflammation was aggravated through activation of the TLR4-p38MAPK/NF-κB signaling cascade and elevated levels of IL-1β and TNF-α. Metagenomic sequencing revealed significant gut microbial dysbiosis, and metabolomics showed disruptions in phenylalanine, tryptophan, and tyrosine metabolism, with phenylalanine metabolism being the most affected, further supporting MGB axis dysfunction. Dietary RES supplementation alleviated behavioral abnormalities in a dose-dependent manner, normalized HPA axis activity, mitigated hypothalamic injury, restored neurotransmitters and cytokines, improved intestinal barrier integrity, and partially reversed gut microbial disruptions. In conclusion, dietary RES effectively ameliorates multiple stress-induced neurobehavioral and intestinal impairments by regulating the MGB axis, offering a promising feed approach to improve poultry resilience and welfare under intensive production conditions.

Chronic and multifactorial stressors, including low-temperature exposure, represent major challenges in modern poultry systems. This study evaluated the effects of a chronic unpredictable mild stress (CUMS) model on growth performance and intestinal homeostasis in layer chicks. A total of 300 one-day-old chicks were randomly assigned to either a control (CON) group or CUMS group for a 5-week trial. CUMS significantly reduced body weight (BW) and feed intake (ADFI) while increasing the feed conversion ratio (F/G) (P < 0.05). Serum biochemical alterations indicated disrupted protein and lipid metabolism and elevated liver enzyme activity. CUMS markedly increased serum diamine oxidase (DAO) and D-lactic acid (D-LA) levels (P < 0.05). Histological, ultrastructural and immunofluorescence analyses showed villus damage, reduced goblet cells, disrupted tight-junction proteins, and notable mitochondrial abnormalities, including swollen mitochondria, loss of cristae integrity, and increased ROS accumulation; ATP concentrations were significantly reduced across intestinal segments (P < 0.05). Mechanistically, CUMS suppressed humoral immunity and activated TLR4/p38MAPK/NF-κB signaling with increased pro-inflammatory and decreased anti-inflammatory cytokines (P < 0.05). Oxidative stress was evidenced by increased malondialdehyde (MDA) and reduced antioxidant enzyme activities (P < 0.05), alongside inhibition of the Nrf2/HO-1 pathway. Apoptosis was enhanced via mitochondrial and death receptor pathways, with reduced Bcl-2/Bax ratios and elevated cleaved Caspase-3 (P < 0.05). Additionally, the AMPK/SIRT1/PGC-1α pathway and mitochondrial biogenesis-related genes were significantly suppressed (P < 0.05). Overall, multi-stressor CUMS model compromises intestinal homeostasis and growth through convergent inflammatory, oxidative, apoptotic, and mitochondrial mechanisms.

The early developmental window is a critical period for the structural establishment and functional maturation of the central nervous system. During this stage, the proliferation, morphological remodeling, and phenotypic transformation of microglia are essential for neurogenesis, synaptic pruning, and refinement of neural circuits, and their dysregulation is implicated in multiple neurodevelopmental disorders. However, the molecular mechanisms governing early microglial development remain unclear. Retinoid X receptor α (RXRα), a nuclear receptor with key roles in development and immune regulation, has not been fully characterized in this context. Here, we used a mouse model of early-life stress (maternal separation) to assess its impact on hippocampal microglial development and inflammation, and to delineate the role of RXRα. Early-life stress reduced body weight and increased plasma corticosterone in juvenile mice, decreased microglial branching and induced aberrant activation, and elevated hippocampal IL-1β, IL-6, and NF-κB subunits P50 and P65. Treatment with the RXR agonist bexarotene upregulated hippocampal RXRα, partially restored microglial morphological complexity, and markedly suppressed pro-inflammatory cytokines and NF-κB pathway gene expression. In an in vitro microglial inflammation model, the anti-inflammatory effect of bexarotene was dependent on peroxisome proliferator-activated receptor γ (PPARγ), as inhibition of PPARγ attenuated its actions. These findings identify RXRα as a critical transcriptional regulator maintaining early microglial homeostasis and limiting inflammation and provide a theoretical basis for the application of bexarotene in the treatment of neuroinflammatory damage caused by early-life trauma.

The high alkalinity in saline alkali aquaculture can induce oxidative stress, brain damage and even death in fish. Curcumin exhibits dual biological activities as both a free radical scavenger and an inflammation modulator, with additional neuroregulatory capabilities. However, the neural regulatory mechanism of curcumin on carp under high alkalinity stress is still unclear. In this 60-day study, 240 carp were randomly allocated into four experimental groups: a control group (C), a curcumin-supplemented group (Cu), a high-alkalinity challenged group (A), and a high-alkalinity challenged group with curcumin dietary intervention (CuA). Pathological sections indicate that alkalinity induces cell swelling, patchy vacuolization, and reduced Nissl bodies in the telencephalon. Maze test found that the diet time and error frequency of carp increased after high alkali stress. After treatment with curcumin, there was a significant reduction in dietary time and error frequency, and the damage to the telencephalon was alleviated. High alkalinity stress induces a significant decrease in the activities of SOD, CAT, and GSH-PX in brain tissue, and a significant increase in MDA content. After treatment with curcumin, the antioxidant activity significantly increased. Transcriptomics method revealed 859 differentially expressed mRNAs (DEGs) in the brain. KEGG enrichment analysis revealed that the Neuroactive ligand-receptor interaction and Vascular smooth muscle contraction signaling pathways were involved in high-alkalinity stressrelated molecular mechanisms. Alkalinity stress induces oxidative stress and brain damage in brain tissue, and activates the Neuroactive ligand receptor interaction pathway to promote the expression of grpr and erich3, while inhibiting fance expression leads to memory loss; After treatment with curcumin, the expression of grpr and erich3 decreased, while the expression of fance increased. Curcumin may alleviate brain oxidative stress and memory loss mediated by high alkalinity stress through the neuroactive ligand receptor interaction and vascular smooth muscle signaling pathway. This study reveals for the first time the mechanism by which curcumin alleviates neurotoxicity induced by alkalinity stress.

OBJECTIVE:This study aimed to investigate whether intermittent cold stimulation can induce adaptation in broilers to acute cold stress (ACS) by regulating the lipid metabolism of hearts. METHODS:CS0 were kept at normal rearing temperature, while CS3 and CS5 were exposed to 3°C for 3 and 5 hours, respectively, on alternate days lower than CS0 from 15d to 35d. On 50d, broilers in three groups were exposed to ACS at 10°C for 12 hours (Y12). The levels of corticosterone (CORT) and liothyronine (T3), mRNA and protein levels of heart adenosine monophosphate (AMP)-activated protein kinase/mammalian target of rapamycin (AMPK/mTOR) pathway genes were assessed at 36 d, 50 d and Y12. RESULTS:At 36d, mRNA levels of AMPKα, acyl-CoA oxidase (ACO), mTOR, sterolregulatory element binding protein (SREBP), stearoyl-coA desaturase (SCD), acetyl-coA carboxylase (ACC), fatty acid synthase (FAS) and protein level of peroxisome proliferatorsactivated receptor α (PPARα) in CS3 and CS5 were significantly lower than those in CS0 (p<0.05). At 50d, compared to CS0, mRNA levels of PPARα, carnitine palmitoyltransferase1 (CPT1), ACO, tuberous sclerosis complex (TSC), SREBP and SCD, as well as protein levels of p-AMPKα/AMPKα, PPARα and SREBP were significantly increased in CS5 (p<0.05). At Y12, the levels of T3 in CS3 and CS5 were significantly higher than those in CS0 (p<0.05), mRNA levels of CPT1, ACO, SREBP, SCD and protein levels of p-AMPKα/AMPKα, SREBP, and FAS were significantly higher in CS5 than in CS0 and CS3 (p<0.05). However, compared to 50d, at Y12, mRNA levels of AMPKα, CPT1 and ACO in CS3 and CS5 significantly decreased (p<0.05), while protein levels of p-AMPKα/AMPKα significantly increased (p<0.05). CONCLUSION:This study suggested that intermittent cold stimulation at 3°C lower than normal rearing temperature for 5h could help broilers adapt to the ACS by promoting heart lipid metabolism.

Chronic stress induces neuroinflammation, hypothalamic dysfunction, and behavioral abnormalities, contributing to depressive-like states. The function of resveratrol (RES), a natural polyphenolic compound with neuroprotective and antidepressant properties, remains underexplored in avian models. This study evaluated the effects of RES on chronic unpredictable mild stress (CUMS), induced depressive-like behaviors in layer chicks and elucidated underlying mechanisms through integrated multi-omics approaches. Behavioral assessments, including open field test (OFT), tonic immobility (TI), and attention bias test (ABT), confirmed that CUMS significantly suppressed body weight and induced depressive-like behaviors characterized by prolonged immobility and reduced exploratory activity (P < 0.05). RES administration dose-dependently mitigated these behavioral impairments. Histological analyses showed that RES alleviated neuronal damage, inhibited microglial activation, decreased the levels of pro-inflammatory cytokines IL-1β and TNF-α, and increased anti-inflammatory IL-10 levels (P < 0.05). Targeted metabolomics revealed that RES restored hypothalamic neurotransmitter balance by elevating serotonin (5-HT), acetylcholine (ACh), and tryptophan (Trp) levels, while reducing norepinephrine (NE) and glutamate (Glu) concentrations (P < 0.05). Network pharmacology identified 85 putative antidepressant targets of RES, and integration with 700 hypothalamic differentially expressed genes (DEGs) highlighted significant enrichment in NF-κB, MAPK, and PI3K-Akt-mTOR signaling pathways. Western blotting confirmed RES inhibited TLR4/p38 MAPK/NF-κB activation and enhanced phosphorylation of PI3K/Akt/mTOR components (P < 0.05). These findings demonstrate that RES attenuates CUMS induced depressive-like behaviors in layer chicks primarily by modulating neuroinflammation and neurotransmitter metabolism via the MAPK and PI3K-Akt-mTOR pathways, offering mechanistic insights and supporting RES as a nutritional intervention to improve stress resilience in poultry.

Immune stress induced by harsh environment in intensive farming can impair broiler intestinal health. Although music as an environmental intervention can alleviate short-term stress injury, its long-term regulatory mechanism on intestinal inflammation has not been clarified. In this study, we investigated the effects of a music-enriched environment on growth performance, intestinal barrier function, and inflammatory responses in lipopolysaccharide (LPS)-induced immunostressed broilers. AA broilers were randomly divided into four groups: control group (CON), music-enriched environment group (MUC), LPS-induced immune stress group (LPS) and music-enriched environment + LPS group (MUC+LPS). On the 14th, 16th and 18th days, the LPS and MUC+LPS groups were injected intraperitoneally with 500 μg of LPS to construct an immune stress model, and the CON and MUC groups were injected with an equal amount of saline. On day 28, the birds were sacrificed to detect the indicators associated with intestinal barrier and inflammation. The LPS group showed a significant decrease in performance from 14 to 28 days, with elevated serum levels of CORT, ACTH, DAO, and d-LA, and a decrease in the activity of intestinal mucosal SOD/GSH-Px, and impaired gut morphology. impaired; music remission significantly alleviated the decline in production performance, reduced the levels of stress hormones and markers of intestinal barrier damage, while elevating jejuno-ileal GSH-Px activity and improving intestinal morphology. Significant inflammatory gene expression characteristics were observed in jejunum and ileum tissues after LPS injection: upregulation of TLR4, NF-κB, TNF-α, IL-1β, and IL-6, and significant suppression of jejunal IL-10 expression. Notably, IL-10 and IFN-γ expression in the ileum did not show statistical differences. Inflammation-related gene expression showed an overall down-regulation trend after the music intervention, but was still significantly different from the control group. Music intervention on the regulation of jejunal MYD88 and ileal TNF-α - the LPS group did not show statistically significant differences in the expression of these two key inflammatory nodes with the LPS+MUS group. Mechanistic studies have shown that LPS triggers an oxidative stress cascade through activation of the TLR4/NF-κB signaling axis, leading to disruption of intestinal barrier integrity. In contrast, music exposure exerts a protective effect through a dual mechanism: on the one hand, it helps to enhance the expression of the tight junction protein ZO-1/Occludin to repair the physical barrier; on the other hand, it inhibits the activation of the TLR4/NF-κB pathway, which can effectively alleviate LPS-induced immunopathological damage.

To investigate the potential protective effect of intermittent cold stimulation in pectoral muscle of broilers. Firstly, we had divided broilers into control (CC) and cold exposure (C3 and C9) groups. Myoblasts were divided into control (C37) and cold exposure (C32 and C27) groups. The results showed that the value of L∗ (lightness) and a∗ (redness) in C9 group were lower than CC and C3 groups, whereas the value of b∗ (yellowness) and drip loss (Myofibre leakage and loss of water, iron and protein during the transition from muscle to meat) was higher than C3 group. The results showed that the mRNA and protein levels of HSPs were significantly higher in the C9 group compared with the CC group. Additionally, apoptosis-associated protein levels of Bcl-2/Bax, CytC, Caspase3, Caspase9 and Caspase8 were significantly elevated in the cold stimulation group, but the levels of Bcl-2/Bax were significantly reduced in the C9 group. Meanwhile, cold-stimulation increased CAT levels and activated the Nrf2 signaling pathway in the C3 group, but not in the C9 group. Moreover, AMPK and PGC-1α were significantly increased after cold stimulation. In vitro results showed that the protein levels of HSP60 and HSP70 were significantly reduced in the C32 and C27 groups compared with the C37 group. Moreover, apoptosis-related protein levels of Bcl-2/Bax, CytC, Caspase3, Caspase9 and Caspase8 were significantly increased in the cold-stimulated group. Cold stimulation increased the mRNA levels of GPx and decreased the mRNA levels of CAT and SOD2 in the C32 group. Meanwhile, the Nrf2 signaling pathway was activated in the cold-stimulated group. Additionally, AMPK and PGC-1α were significantly increased in the C32 group and significantly decreased in the C27 group compared with the C37 group. Therefore, intermittent mild cold-stimulation improved antioxidative function and energy metabolism by activated Nrf2/Keap1/AREs and AMPK/PGC-1α signaling pathway in broiler pectoral muscle.

Music as an environmental factor can maintain intestinal health in animals, but it is unclear whether this effect is influenced by the tones of the music. In this study, 100 Kunming white mice were randomly divided into control group (C group) with no music, and three music groups were exposed to Mozart K.448 in D, A and G tone (D group, A group and G group), respectively. To study the effects of different tones of Mozart K.448 on intestinal barrier and intestinal microbiota, mice were given musical stimulation from 1 to 63 days of age. The results showed that no apparent abnormalities were observed in the structure of ileum among groups. The mRNA expression levels of genes related to intestinal physical barrier (Claudin-1, Claudin-12, ZO-2, Mucin2, ZO-1 and Claudin-5) were significantly higher in music groups than those in C group (p < 0.05), and the mRNA expression levels of intestinal barrier genes in D group were the highest (p < 0.05). The levels of intestinal mucosal permeability (DAO and D-lactate) in D group were significantly lower than those in other groups (p < 0.05). Ileum HSP60 mRNA level in D group were significantly lower than that in other groups (p < 0.05). The mRNA expression level of IgA was significantly higher in music groups than C group (p < 0.05). Additionally, the mRNA and protein expression levels of IgG were significantly higher in D group than other groups (p < 0.05). Music stimulation increased the abundance of beneficial microbiota, such as Lactobacillus and Sporosarcina (p < 0.05). Mozart K.448 can strengthen intestinal barrier function to reduce intestinal permeability and improve intestinal immunity, while also having a positive significance in promoting the colonization of beneficial intestinal microbiota. In addition, the effect of tone D was more significant.

Adverse events in early life can alter the developmental trajectory of glial cells and neurons in the brain, increasing an individual's risk of developing neuropsychiatric disorders later in life. Retinoid X receptor alpha (RXRα), a member of the nuclear receptor superfamily, has been shown to exert protective effects on the central nervous system when activated. However, whether RXRα plays a role in maternal separation (MS) and the underlying mechanisms remain unclear. In this study, we used MS in BALB/c mice to simulate early-life stress, aiming to investigate the impact of MS on hippocampal neuronal development in mice during early life, as well as the neuroprotective role of RXRα and its mechanisms. The results showed that MS induced hippocampal neuronal damage and inhibited RXRα expression in offspring mice. In contrast, RXRα activation significantly ameliorated hippocampal neuronal damage in MS mice and exerted neuroprotective effects by suppressing oxidative stress, repairing mitochondrial dysfunction, reducing neuronal apoptosis, and promoting mitophagy. Further analysis revealed that bexarotene (an RXR agonist) exerted neuroprotective effects by upregulating the expression levels of RXRα and peroxisome proliferator-activated receptor gamma (PPARγ). In HT22 cells with hydrogen peroxide (H2O2)-induced damage, knockdown of PPARγ expression via small interfering RNA (siRNA) significantly attenuated the neuroprotective effect of RXRα activation against neuronal damage. In conclusion, MS impairs the development of hippocampal neurons in offspring mice, which may alter the developmental trajectory of the nervous system and increase the risk of neuropsychiatric disorders in adulthood. Activation of RXRα can effectively alleviate oxidative stress and neuronal damage in the hippocampus by improving mitochondrial dysfunction. Therefore, targeting RXRα holds promise as a potential strategy for treating the consequences of early-life trauma.

Cold exposure (CE) affects the growth and health of poultry. Resveratrol (RES) exerts antioxidation and anti-inflammation functions and is used as a feed additive to reduce the impact of environmental factors on poultry. To explore the impacts of CE on broiler heart and the protentional protective effect of RES, 360 twenty-one-day-old Arbor Acres broilers were housed under the normal ambient temperature (CON, 22 ± 2 °C) or CE temperature at 8 ± 1 °C for 10 h/day at days 28-42, and provided the basal diet supplemented with RES at graded levels (0, 250, 500, and 750 mg RES/kg diet) from days 21-42. The results showed that CE reduced body weight gain and caused inflammatory cells infiltration and inflammation by upregulating NF-κBp65, COX-2, and iNOS at both mRNA and protein levels (P < 0.05). CE caused apoptosis by upregulating Bax, Cyt C, Caspase 3, and Caspase 9 and downregulating Bcl2 mRNA and protein expression and Bcl2/Bax ratio (P < 0.05), and destroyed energy metabolism homeostasis by decreasing HK2 and LDHA mRNA and protein expression and downregulating HK1, LDHB, PFK, PK, and SDHB mRNA expression in the heart (P < 0.05). CE upregulated p38 and inhibited PI3K and AKT mRNA and protein expression (P < 0.05). However, RES supplemented into the diet with a dosage of 500 mg/kg feed could significantly improve body weight gain of broilers, reduce inflammatory response and apoptosis, and enhance energy metabolism in cold-exposed broiler heart (P < 0.05) through regulation of the p38-PI3K/AKT-NF-κB axis. Overall, this experiment reveals the protective effects of RES on cardiac injury and energy metabolism disorder caused by cold exposure in broilers. Therefore, dietary RES supplementation is a practical strategy to mitigate the adverse impacts of cold on broilers reared in cold regions.

Cold climate is a severe challenge to the sustainability of global poultry production, as it impairs the health and growth performance. Resveratrol (RES) is a natural polyphenol and has antioxidative and anti-inflammatory activities. To investigate whether RES alleviates cardiac substance metabolism disorder caused by cold exposure (CE) via regulating mitochondrial quality control. 28-day-old broilers were subjected to CE at 8 ± 1°C for 14 days and fed the diets with 0, 250, 500, and 750 mg RES/kg feed, respectively. CE reduced body weight, and caused mitochondrial structure abnormalities and lipid droplet formation in the heart. CE elevated reactive oxygen species level, reduced mRNA and protein expression of AMPK and genes related to antioxidative function (Nrf2, HO-1, SOD1, SOD2, CAT, and GPx), mitochondrial biogenesis (Nrf1 and PGC-1α), mitochondrial dynamics (MFF, MFN1, MFN2, and OPA1), and lipolysis (PPARα, CPT1, and ACO2), promoted mRNA and protein expression of dynamin-related protein 1 and genes associated with mitophagy (PINK1, Parkin, ATG5, LC3Ⅱ/Ⅰ, p62, and Beclin1) and lipogenesis (SREBP1, FAS, ACC, and PPARγ), increased the concentrations of triglyceride, total cholesterol and LDLC, and reduced free fatty acids and HDLC concentrations in serum. RES reduced CE-caused oxidative stress and improved mitochondrial health, improving lipid metabolism by regulating the AMPK/PGC-1α/PPAR pathway in broiler heart. Therefore, this study suggests that dietary supplementation with RES, especially a 500 mg/kg dosage, could relieve CE-induced heart injury and dysfunction associated with lipid metabolism disorder by improving the Nrf2/HO-1 pathway-modulated antioxidative defense function and balancing the AMPK signaling-regulated mitochondrial quality control system in broilers.

Moderate cold stimulation regulates the thymus's growth and function and facilitates cold acclimatization in broilers. However, the underlying mechanism remains unknown. To explore the possible mechanism of the thymus in cold-acclimated broilers against cold stress, 240 1-day-old Arbor Acres (AA) broilers were assigned to two groups randomly. The control group (C) was housed at conventional temperatures. The temperature during the first week was 33-34°C. Between the ages of 8 and 32 days, the temperature was lowered by 1°C every two days, i.e., gradually from 32°C to 20°C, and then maintained at 20°C until 42 days of age. The cold-acclimated group (C-3) was housed at the same temperature as C from 1-7 days after birth. Between 8 and 42 days, the temperature of C-3 was 3°C colder than C. After 24 h exposure to acute cold stress (ACS) at 42 days, C and C-3 were named as S and S-3. The results showed that ACS was able to induce oxidation stress, modulate PI3K/AKT signal, and cause necroptosis and apoptosis in broiler thymus. By contrast, cold acclimation could alleviate apoptosis and necroptosis induced by cold stress via alleviating oxidative stress, efficiently activating the PI3K/AKT signal, as well as decreasing apoptotic and necrotic genes’ levels. This study offers a novel theoretical basis for cold acclimation to improve the body's cold tolerance.

To investigate the potential protective effect of prior cold stimulation on broiler intestine induced by acute cold stress (ACS). A total of 384 one-day-old broilers were divided into control (CON), ACS, cold stimulation I (CS3+ACS), and cold stimulation II (CS9+ACS) groups. Broilers in CON and ACS groups were reared normally, and birds in CS3+ACS and CS9+ACS groups were reared at 3 degrees C and 9 degrees C below CON group for 5 h, respectively, on alternate days from d 15 to 35. Broilers in ACS, CS3+ACS, and CS9+ACS groups were subjected to 10 degrees C for 24 h on d 43. Eventually, small intestine tissues were collected for histopathological observation and indexes detection. The results showed that intestinal tissues in all ACS-broilers exhibited inflammatory cell infiltrates, microvilli disruption, reduced villus length in jejunum and increased crypt depth in jejunum and ileum. Whereas these phenomena were relatively light in CS3+ACS group. Compared to CON group, mRNA expression of the TLR4/MyD88/NF-kappa B pathway-related genes (TLR4, MyD88, NF-kappa Bp65, COX-2, iNOS, PTGEs, TNF-alpha), Th1/Th17-derived cytokines (IL-1 beta, IL-2, IL-8, IL-12, IFN-gamma, IL-17), and HSPs (HSP40, HSP60, HSP70, HSP90) was upregulated (P < 0.05), and that of Th2-deviated cytokines (IL-4, IL-6, IL-10, IL-13) and I kappa B alpha was downregulated (P < 0.05) in small intestine in almost all ACS-broilers. Compared to ACS group, mRNA expression of most of the TLR4/MyD88/NF-kappa B pathway-related genes, Th1/Th17-derived cytokines, and HSPs was downregulated and that of Th2-derived cytokines was upregulated in CS3+ACS group (P < 0.05). Protein expression levels of TLR4, MyD88, p-p65/p65, p-I kappa B alpha/I kappa B alpha, IKK, TNF-alpha, IL-1 beta, IL-10, and HSPs were similar to their mRNA expression. The concentration of sIgA and activities of CAT, SOD, and GSH-px were decreased and MDA and H2O2 were increased in ACS and CS9+ACS groups compared to CON group (P < 0.05). Therefore, cold stress caused oxidative stress and inflammation, leading to gut immune dysfunction; while mild cold stimulation at 3 degrees C below normal rearing temperature alleviated cold stress-induced intestinal injure and dysfunction by modulating the TLR4/MyD88/NF-kappa B pathway in broilers.

The rise of operational noise as an environmental pollutant for farm animals is an emerging concern. The mechanisms through which music can alleviate oxidative stress, inflammation, and apoptosis induced by noise exposure remain underexplored. This study aims to investigate the alleviating effects and underlying mechanisms of long-term music exposure on noise-induced damage to the chicken spleen. Male Arbor Acres (AA) broilers were divided into four groups: control (C), acute noise stimulation (NS), noise stimulation with music mitigation (NSM), and music only (M). NS and NSM groups were exposed to noise (simulating sudden intensity noise, 115 to 120dB) for 10 minutes daily for a week, starting at 14-days-old. NSM and M groups then received 28 days of 6-hour daily music (Mozart K.448, 60-65 dB). The results showed that noise stimulation significantly activated the Keap-1/Nrf2 and NF-κB signaling pathways. Long-term music intervention has also been demonstrated to successfully mitigate oxidative stress and abnormal apoptosis induced by acute noise stimulation. Microscopic examination of the spleen revealed that acute noise stimulation resulted in an increase in splenic cells, a decrease in lymphocytes, and blurred boundaries between the red and white pulps in the NS group. However, these pathological changes were alleviated in the NSM group following music intervention. Compared with the control group, the NS group exhibited significantly elevated oxidative stress parameters. In contrast, music intervention in the NSM group notably improved antioxidant capacity and partially alleviated morphological abnormalities in the spleen. Additionally, noise stimulation activated the NF-κB pathway, upregulating the downstream genes of the inflammatory factors IL-1β, IL-6, and TNF-α. Noise-induced mitochondrial damage led to apoptosis, as observed by TUNEL staining, along with increased gene and protein expression of Bcl-2, Bax, Cyt-C, Casp-3, Casp-8, and Casp-9. These findings indicate that acute noise exposure can induce splenic damage via oxidative stress, inflammation, and apoptosis by modulating the Keap-1/Nrf2 and NF-κB pathways. Prolonged music stimulation effectively mitigates noise-induced damage, offering a vital experimental foundation for further research on noise pollution's impact on organisms and music's alleviating role.

As an environmental enrichment, music can positively influence the immune function, while noise has an adverse effect on the physical and mental health of humans and animals. However, whether music-enriched environments mitigate noise-induced acute stress remains unclear. To investigate the anti-inflammatory effects of music on the immune organs of broiler chickens under conditions of early-life acute noise stress, 140 one-day-old white feather broilers (AA) were randomly divided into four groups: control (C), the music stimulation (M) group, the acute noise stimulation (N) group, the acute noise stimulation followed by music (NM) group. At 14 days of age, the N and NM groups received 120 dB noise stimulation for 10 min for one week. After acute noise stimulation, the NM group and M group were subjected to continuous music stimulation for 14 days (6 h per day, 60 dB). At 28 days of age, the body temperature of the chicks, the histopathological changes, quantification of ROS-positive density and apoptosis positivity in tissues of spleen, thymus, and bursa of Fabricius (BF) were measured. The results showed that acute noise stimulation led to an increase in the number and area of splenic microsomes and the cortex/medulla ratio of the detected immune organs. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) of immune tissues of broilers in N group were decreased compared to the broilers in C group, while the mRNA levels of malondialdehyde (MDA), TNF-α, IL-1, and IL-1β increased. In addition, the gene and protein expression levels of IKK, NF-κB, and IFN-γ of three immune organs from broilers in the N group were increased. Compared to the C and N group, chickens from the NM group showed a decrease in the number and area of splenic follicles, an increase in the activities of SOD and GSH-Px, and a decrease in the expression levels of MDA, TNF-α, IL-1, and IL-1β. Therefore, a music-enriched environment can attenuate oxidative stress induced by acute noise stimulation, inhibiting the activation of the NF-κB signaling pathway and consequently alleviating the inflammatory response in immune organs.

Intermittent cold stimulation (ICS) enhances broilers’ resistance to cold stress. Nonetheless, further research is needed to investigate the underlying mechanisms that enhance cold stress resistance. A total of 160 one-day-old male Ross 308 broilers were randomly divided into 2 groups (CC and CS5), with the CC group managing temperature according to the standard for broiler growth stages, while the CS5 group were subjected to cold stimulation at a temperature 3℃ lower than the CC group for 5 h, every 2 d from 15 to 35 d. Sampling was conducted at 36 d (36D), 50 d (50D) and after acute cold stress for 24 h (Y24). First, we examined the effects of ICS on broiler growth performance, meat quality, antioxidant capacity, and lipid metabolism. The results demonstrated that ICS enhanced the performance of broilers to a certain degree. Specifically, the average weight gain in the CS5 group was significantly higher than that of the CC group, and the feed conversion ratio significantly decreased compared to CC at 4 W and 6 W (P ≤ 0.05). Compared with the CC group, cold stimulation significantly reduced drip loss, shearing force, and yellowness (a* value) of chicken meat, while significantly increased redness (b* value) (P ≤ 0.05). At Y24, the levels of T-AOC and GSH-PX in the serum of the CS5 group were significantly higher than those of the CC group, while the level of MDA was significantly lower (P ≤ 0.05). The content of TG, FFA, and VLDL in the serum of the CS5 group was significantly elevated, whereas the level of TC and HDL was significantly lower (P ≤ 0.05). In addition, we further explored whether AMPK-mTOR pathway is involved in the regulation of changes in lipid metabolism and the possible regulatory mechanisms downstream of the signaling pathway. The results showed that ICS significantly upregulated the expression levels of AMPK mRNA and protein in the liver of the CS5 group at 36D and Y24, while significantly down-regulating mTOR (P ≤ 0.05). Compared with the CC group, ICS significantly down-regulated the mRNA expression levels of lipid synthesis and endoplasmic reticulum stress-related genes (SREBP1c, FAS, SCD, ACC, GRP78 and PERK) at 36D and Y24, while significantly up-regulating the mRNA expression levels of lipid decomposition and autophagy-related genes (PPAR and LC3) (P ≤ 0.05). In addition, at Y24, the protein expression levels of endoplasmic reticulum stress-related genes (GRP78) in the CS5 group were significantly lower, while autophagy-related genes (LC3 and ATG7) were significantly higher (P ≤ 0.05). ICS can affect meat quality and lipid metabolism in broilers, and when broilers are subjected to acute cold stress, broilers trained with cold stimulation have stronger lipid metabolism capacity.

Introduction:High-alkalinity water is a serious health hazard for fish and can cause oxidative stress and metabolic dysregulation in fish livers. However, the molecular mechanism of liver damage caused by high alkalinity in fish is unclear. Methods:In this study, 180 carp were randomly divided into a control (C) group and a high-alkalinity (A25) group and were cultured for 56 days. High-alkalinity-induced liver injury was analysed using histopathological, whole-transcriptome, and metabolomic analyses. Results:Many autophagic bodies and abundant mitochondrial membrane damage were observed in the A25 group. High alkalinity decreased superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activity and the total antioxidant capacity (T-AOC) and increased the malondialdehyde (MDA) content in liver tissues, causing oxidative stress in the liver. Transcriptome analysis revealed 61 differentially expressed microRNAs (miRNAs) and 4008 differentially expressed mRNAs. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that mammalian target of rapamycin (mTOR), forkhead box O (FoxO), mitogen-activated protein kinase (MAPK), and the autophagy signalling pathway were the molecular mechanisms involved. High alkalinity causes oxidative stress and autophagy and results in autophagic damage in the liver. Bioinformatic predictions indicated that Unc-51 Like Kinase 2 (ULK2) was a potential target gene for miR-140-5p, demonstrating that high alkalinity triggered autophagy through the miR-140-5p-ULK2 axis. Metabolomic analysis revealed that the concentrations of cortisol 21-sulfate and beta-aminopropionitrile were significantly increased, while those of creatine and uracil were significantly decreased. Discussion:The effects of high alkalinity on oxidative stress and autophagy injury in the liver were analysed using whole-transcriptome miRNA-mRNA networks and metabolomics approaches. Our study provides new insights into liver injury caused by highly alkaline water.

Sirtuins (SIRTs) were originally characterized by yeast Sir2 as a lifespan regulator that is conserved in all three structural domains of bacteria, archaea and eukaryotes and belong to histone deacetylases consisting of seven members (SIRT1-SIRT7). Surprisingly, SIRTs have been shown to play important regulatory roles in almost all cellular functions, including mitochondrial biogenesis, oxidative stress, inflammation, cell growth, energy metabolism, neural function, and stress resistance. Among the SIRT members, sirtuin 3 (SIRT3) is one of the most important deacetylases that regulates the mitochondrial acetylation and plays a role in pathological processes, such as metabolism, DNA repair, oxidative stress, apoptosis and ferroptosis. Therefore, SIRT3 is considered as a potential target for the treatment of a variety of pathological diseases, including metabolic diseases, neurodegenerative diseases, age-related diseases and others. Furthermore, the isolation, screening, and development of SIRT3 signaling agonists, especially from natural products, have become a widely investigated objective. This paper describes the structure of SIRT3 protein, discusses the pathological process of SIRT3-mediated acetylation modification, and reviews the role of SIRT3 in diseases, SIRT3 activators and its related disease studies.