Influence of Trans-anethole on the nutrient digestibility and intestinal barrier function in broilers

Tetrastigma hemsleyanum as a feed additive: modulating gut microbiota for enhancing nutritional transport and growth performance in Jinhua yellow chickens

Tetrastigma hemsleyanum (TH) has attracted much attention for its heat clearing and detoxification effects, but whether it can become an effective feed supplement in chickens remains unclear. Herein, a total of 120 male Jinhua yellow chickens (two-mth-old) were randomly divided into into four groups (CON, TH-L, TH-M, and TH-H) for a 56-day feeding trial to explore its effects on growth performance and underlying mechanism. Results revealed that dietary TH notably increased the average daily growth (ADG), and decreased the average daily feed intake (ADFI) and feed conversion ratio (FCR) in TH-H group during 29-56 days. Meanwhile, dietary TH improved the development of duodenum and notably increased the contents of essential amino acids and flavor amino acids, while the serum oxidation stress index as well as abdominal fat deposition were not affected in Jinhua yellow chickens. Additionally, TH supplementation notably increased gut microbiota richness, then selectively increased the colonization of potential probiotics and the microbial abundance associated to amino acid synthesis and metabolic pathways in duodenum. Furthermore, qPCR analysis results preliminarily verified that dietary TH not only enhanced intestinal amino acids (rBAT and EAAT3) and peptides (PepT1 and APN) transport but also alleviated the inflammation (IL-1β, IL-6 and IFN-γ), thus thereby improved intestinal development and growth performance in Jinhua yellow chickens. These findings demonstrated that TH is a feed additive that can improve growth performance, muscle amino acids composition and intestinal development.

Dietary encapsulated fennel seed (Foeniculum vulgare Mill.) essential oil supplementation improves performance, modifies the intestinal microflora, morphology, and transcriptome profile of broiler chickens

Global antimicrobial resistance has led to a ban on the use of antibiotics as growth promoters (AGPs) in poultry farming, encouraging the use of natural phytogenic feed additives that provide similar effects to AGPs without causing resistance. The aim of this study was to determine the effects of the addition of encapsulated fennel seed (Foeniculum vulgare Mill.) essential oil (FEO) into the diets on the performance, intestinal microflora, morphology, and transcriptomic profiling of broiler chickens. In the study, 400 one-d-old male chicks of the Ross-308 genotype were randomly distributed into five groups, each with 16 replicates of five birds. The experiment included a control group fed on basal diets without the addition of FEO and treatment groups supplemented with 50 (FEO50), 100 (FEO100), 200 (FEO200), or 400 (FEO400) mg of encapsulated FEO/kg. Body weight and the European Production Efficiency Factor values were higher in the FEO100, FEO200, and FEO400 groups (P < 0.05). The feed conversion ratio significantly improved at all FEO levels (P < 0.05). FEO supplementation improved duodenum, jejunum, and ileum morphologies. It enhanced mucosal layer thickness in the duodenum and jejunum, and muscular layer thickness in the jejunum and ileum (P < 0.05). It also increased the number of Lactobacillus spp. in the jejunum and ileum (P < 0.05). According to the transcriptome profile obtained from the microarray analysis of samples taken from small intestine tissues, the mRNA expression levels of 261 genes in the FEO50 group (206 upregulated and 55 downregulated), 302 genes in the FEO100 group (218 upregulated and 84 downregulated), 292 genes in the FEO200 group (231 upregulated and 61 downregulated), and 348 genes in the FEO400 group (268 upregulated and 80 downregulated) changed compared to the control group. Most upregulated genes were associated with catalytic activity, binding, transcription regulators and transcription factors, anatomical structure and cellular development, and protein binding activity modulators. The downregulated genes mostly belonged to the transporter, carrier, and protein-modifying enzyme classes. Besides, the anti-inflammatory IL-10 gene (4.41-fold) increased significantly in the FEO100 group compared to the control group (P < 0.05). In conclusion, FEO improved the performance of broiler chickens by regulating biological processes such as performance and intestinal health, with the 100 mg FEO/kg supplementation being the most prominent.

Trans-Anethole Alleviates DSS-Induced Ulcerative Colitis by Remodeling the Intestinal Flora to Regulate Immunity and Bile Acid Metabolism

Ulcerative colitis (UC) is the most common inflammatory bowel disease (IBD); it is incurable, and the treatment is expensive. Trans-anethole (TA), the main component of fennel, exhibits various biological activities. An increasing number of studies have demonstrated the efficacy of herbal active ingredients in the treatment of UC. This study aimed to investigate the effect and mechanism of TA in UC. In this study, we have experimented on mice with dextran sulfate sodium salt (DSS)-induced UC. The TA group was gavaged with 62.5 mg/kg TA by gavage once daily on days 8-14. To observe the effect of TA on the colon tissue, various investigations were performed, including western blot and immunohistochemistry for intestinal barrier protein expression, TUNEL staining for apoptosis, western blot, and ELISA for inflammation level, flow cytometry for Th17/Treg, LC-MS for blood bile acid content, GC-MS for blood fatty acid content, and 16s RNA for intestinal contents. TA alleviated weight loss in mice with UC; increased colon length; alleviated intestinal mucosal damage; upregulated claudin-1, occludin, and ZO-1 protein expression levels; reduced inflammatory factors in the colon and serum; and alleviated apoptosis. TA reduced fatty acid and bile acid levels by inhibiting colony abundance and reducing Th17/Treg cell differentiation in the colon. We found that TA alleviates DSS-induced UC by remodeling the intestinal flora to regulate immunity and bile acid metabolism.

Effects of organic zinc on production performance, meat quality, apparent nutrient digestibility and gut microbiota of broilers fed low-protein diets

The high cost of feed and nitrogen pollution caused by high-protein diets have become major challenges restricting sustainable development in China's animal husbandry sector. Properly reducing protein levels and improving protein utilization in feed are effective approaches to solving this problem. To determine the optimal dose of methionine hydroxyl analogue chelated zinc (MHA-Zn) in broiler diets with a 1.5% reduction in crude protein (CP), a total of 216 1-day-old broilers were randomly assigned into 4 groups (each group consisted of 3 replications with 18 broilers per replicate), and growth and development indexes were assessed after 42 days. The broilers in control group were fed a basic diet, whereas those in the three test groups were fed diets with a 1.5% reduction in CP. The results showed no significant difference in the edible parts of broilers between low-protein (LP) diet group (90 mg/kg MHA-Zn) and normal diet group (p > 0.05), and adding 90 mg/kg MHA-Zn to LP diet significantly improved ileum morphology and apparent total tract digestibility (ATTD) of nutrient (p < 0.01; p < 0.05). A 16S rRNA sequencing analysis indicated that supplementing the LP diet with 90 mg/kg MHA-Zn was adequate for production performance of broilers and promoted beneficial bacteria in the cecum (Lactobacillus, Butyricoccus, Oscillospira, etc.) (p < 0.01). In summary, adding an optimal dose of organic zinc (90 mg/kg MHA-Zn) in low protein diets led to enhanced production performance of broilers and optimized cecum microbiota. Additionally, the reduction of crude protein consumption in broiler production proved to be a cost-effective measure, while also mitigated nitrogen pollutant emissions in the environment.

Immunomodulatory effects of trans-anethole-treated Staphylococcus aureus Newman strain

In our former studies based on a human whole-blood model infected with trans-anethole (TA)-treated Staphylococcus aureus Newman strain, we have observed that selected parameters/mechanisms of innate and acquired immune response were more enhanced in comparison to samples infected with non-treated bacteria. Due to this observation, the current study aimed to evaluate the concentration of selected proteins involved in both types of responses (IL-1α, IL-1β, IL-2, IL-6, IL-12, IL-17, TNF-α, IFN-γ, G-CSF, C5a, CCL1-CCL5, CXCL1, CXCL2, CXCL9-CXCL11, MMP-8, TLR2, and PGLYRP1) in healthy participants' plasma after blood stimulation of TA-treated S. aureus Newman strain. Determination of analyzed protein concentration was conducted using Luminex and ELISA assays. Based on the results, it has been proven that the immunomodulatory potential of TA-treated S. aureus Newman strain on increasing IL-1β, IL-6, TNF-α, IL-12, G-CSF, C5a, CCL2-CCL4, CXCL1, CXCL2, MMP-8 and PGLYRP1 levels in plasma. Moreover, it has been also demonstrated an association between TNF-α and CCL4 in a blood model infected with TA-treated cells. More research is warranted to find more underlying mechanisms involved in the effects of TA-treated S. aureus Newman in human blood, mainly whether the observed "immunity boost" can be regulated after bacteria elimination. Therefore, the potential of TA should be further explored to understand under which conditions it might help treat or prevent infections caused by S. aureus.

Trans-anethole exerts protective effects on lipopolysaccharide-induced acute jejunal inflammation of broilers via repressing NF-κB signaling pathway

This study aimed to explore the effects of trans-anethole (TA) on lipopolysaccharide (LPS)-induced acute jejunal inflammation model of broilers. A total of 160 one-day-old broilers (male; Arbor Acres) were randomly allocated into four treatment groups with 8 replicates of 5 birds each. On d 20, the dose of 5 mg/kg body weight LPS solution and the equal amount of sterile saline were intraperitoneally injected into LPS-challenged and unchallenged broilers, respectively. Compared with the control group, LPS decreased (P < 0.05) the villus height (VH) and the ratio of villus height to crypt depth (VCR) but increased (P < 0.05) the crypt depth (CD), meanwhile, enhanced (P < 0.01) the levels of interleukin-6 (IL-6), interleukin-1beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) but decreased (P < 0.01) the level of interleukin-10 (IL-10). The group supplemented with 600 mg/kg of TA had lower (P < 0.01) CD and higher (P < 0.01) VCR than the LPS group. TA increased (P < 0.01) the level of IL-10 and decreased (P < 0.01) the level of IL-1β. The mRNA expression levels of IL-6, nuclear factor kappa B (NF-κB), TNF-α were up-regulated (P < 0.05) and the levels of IL-10 and inhibitor of NF-κB alpha (IκBα) were down-regulated (P < 0.05) by LPS as compared with the control group. TA down-regulated (P < 0.05) the increased mRNA expression levels of genes caused by LPS, as well as up-regulated (P < 0.05) the levels of IL-10 and IκBα. Furthermore, LPS down-regulated (P < 0.05) and up-regulated (P < 0.05) the protein expression levels of IκBα and NF-κB p65, respectively. TA up-regulated (P < 0.05) the level of IκBα and down-regulated (P < 0.05) the level of NF-κB p65. The conclusion of this study is that TA could exert protective effect on the LPS-induced acute jejunal inflammation of broilers via repressing the activation of NF-κB and the 600 mg/kg is the optimal dose against LPS-induced acute jejunal inflammation of broilers.

Trans-anethole ameliorates LPS-induced inflammation via suppression of TLR4/NF-κB pathway in IEC-6 cells

This study was undertaken to investigate the protective role of trans-anethole (TA) in lipopolysaccharide (LPS)-induced rat intestinal epithelial cells (IEC-6) injury and the potential mechanisms. The cells were pretreated with TA (0 and 1 mM) for 24 h, prior to stimulation by LPS (1 mg/mL) for 24 h. Compared with the control group (CON), LPS stimulus resulted in decreased cell viability, intestinal barrier injury, increased cell apoptosis and cell cycle arrest at the G2/M phase. These effects triggered by LPS were reversed by TA. In order to reveal the main genes and pathways involved among the groups, transcriptome analysis was performed to identify the differential expression genes (DEGs) among the treatment groups. There were a total of 493 DEGs (275 upregulated and 218 downregulated) that were identified between the LPS and CON group. Meanwhile, a total of 361 DEGs (103 regulated and 258 downregulated) were identified in the LPS+TA group compared with the LPS group. The results showed that the DEGs were mostly enriched in immune related pathways, such as tumor necrosis factor (TNF) signaling pathway, cytokine-cytokine receptor interaction, complement and coagulation cascades, interleukin-17 (IL-17) signaling pathway, NF-kappa B (NF-κB) signaling pathway, antigen processing and presentation, and NOD-like receptor signaling pathway. Based on the results of RNA-sequencing, further investigation of the signaling pathway involved revealed that TA could inhibit the activation of toll like receptor 4 (TLR4)/NF-κB signaling pathway and NLR family pyrin domain containing 3 (NLRP3) inflammasome in LPS-induced IEC-6 cells. In conclusion, this finding demonstrated a functional role of TA in intestinal epithelial cells injury and indicated that TA may be a potential strategy for treatment of inflammatory intestinal diseases.

Trans-anethole Ameliorates Intestinal Injury Through Activation of Nrf2 Signaling Pathway in Subclinical Necrotic Enteritis-Induced Broilers

This study was conducted to investigate the alleviative effects of trans-anethole (TA) on intestinal oxidative stress by enhancing the activities of intestinal antioxidant enzymes and activating the Nrf2 signaling pathway in subclinical necrotic enteritis (NE) infected broilers. A total of 192 1-day-old male Arbor Acres broilers were randomly allocated into three treatment groups: (1) control (CON); (2) subclinical NE challenge (NE); (3) NE challenge + 600 mg/kg TA (NE+TA600). Subclinical NE was induced by oral administration of live coccidiosis vaccine containing 2 × 10⁴ oocysts at 10 days of age and 2 ml of Clostridium perfringens type A solution (3 × 10⁸ CFU/ml) daily from days 14 to 19. The results showed that NE infection led to a severe decline (p < 0.05) in the final body weight (BW) and average daily gain (ADG), but an increase (p < 0.05) in feed/gain (F/G) of broilers at day 10–21 and day 1–21 compared with the control group. TA administration improved (p < 0.05) the growth performance of NE birds. The intestinal villus height (VH) and villus height/crypt depth (VH/CD) were reduced (p < 0.05) by NE challenge as compared with those of the control group, which was elevated by TA administration. Subclinical NE infection decreased (p < 0.05) serum activities of total superoxide dismutase (T-SOD), total antioxidant capacity (T-AOC), and jejunal and ileal glutathione peroxidase (GSH-PX), and T-SOD activity as well as T-AOC in the jejunum, while TA interventions positively elevated that (p < 0.05). Administration of TA protected the intestine against oxidative stress through up-regulation of intestinal nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway as compared with the NE group (p < 0.05). In addition, dietary inclusion of TA elevated (p < 0.05) mRNA abundance of c-mesenchymal-epithelial transition factor (c-Met), jejunal epidermal growth factor receptor (EGFR), and transforming growth factor-beta 1 (TGF-β1) in the jejunum and ileum of birds after subclinical NE challenge. In conclusion, 600 mg/kg of TA may be a promising tool to prevent and control subclinical NE by increasing intestinal antioxidant status in broilers.

Trans-Anethole Alleviates Subclinical Necro-Haemorrhagic Enteritis-Induced Intestinal Barrier Dysfunction and Intestinal Inflammation in Broilers

This study investigated the alleviative potential of trans-anethole (TA) on the impaired intestinal barrier and intestinal inflammation and its regulatory effects on gut microbiota in broilers with subclinical necro-hemorrhagic enteritis (NE) challenge. Subclinical NE challenge led to a severe decline in the 21-day body weight (BW) and average daily gain (ADG), but an increase in feed conversion ratio (FCR) and intestinal lesion score of birds compared with controls (P < 0.05). Compared with the subclinical NE group, the TA administration group exhibited lower (P < 0.05) intestinal lesion score and crypt depth (CD), serum diamine oxidase activity, and D-lactate concentration, but higher (P < 0.05) intestinal tight junction protein expressions, villus height (VH), VH/CD, and numbers of proliferating cell nuclear antigen (PCNA)-positive cells. The administration of TA also inhibited (P < 0.05) the expression of intestinal pro-inflammatory cytokines including interleukin (IL)-1β, IL-8, interferon-gamma (IFN-γ), and tumor necrosis factor-alpha (TNF-α) but increased (P < 0.05) jejunal IL-10 and secretory immunoglobulin A (sIgA) concentration. TA inclusion also led to a remarkable reduction of intestinal NF-kappa-B inhibitor alpha (IκBα) degradation and nuclear factor kappa beta (NF-κB) translocation. Moreover, TA modulated the cecal microbiota abundance and diversity of NE birds, as confirmed by reducing the phylum Firmicutes and genera Ruminococcaceae_UCG-014, Eubacterium_coprostanoligenes_group, and Ruminococcaceae_NK4A214_group when supplemented at 600 mg/kg and reducing genera Butyricicoccus, Oscillibacter, and Flavonifractor when supplemented at 400 mg/kg (P < 0.05). Supplementation of TA in broiler diets could alleviate subclinical NE infection by restoring intestinal barrier integrity, inhibiting NF-κB signaling pathway, and modulating gut microbiota. A 600-mg/kg dose of TA is the optimum concentration for ameliorating subclinical NE in broilers.