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In the myocardial infarction microenvironment, the effect of macrophages on the function of bone marrow mesenchymal stem cells (BMSCs) is unclear. In this study, we investigated the role of hypoxia/serum deprivation (H/SD)-induced M1-type macrophage-derived exosomes on BMSC viability, migration, and apoptosis. We found that H/SD reduced BMSC viability and migration, increased BMSC apoptosis, and induced macrophage polarization toward the M1 phenotype. BMSCs were cultured by the supernatant of H/SD-induced THP-1 cells (M1-type macrophages) with or without exosome inhibitor treatment. The results show that BMSC apoptosis is increased in the H/SD-induced THP-1 cell supernatant group and is decreased by GM4869 treatment, indicating that M1-type macrophages induce BMSC apoptosis through exosomes. In addition, we confirm that miR-222 plays an important role in promoting BMSC apoptosis by targeting B-cell lymphoma (Bcl)-2. M1-type macrophage-derived exosomes significantly decrease BMSC viability and migration and increase BMSC apoptosis, and these effects are partly abolished by a miR-222 inhibitor. Our findings suggest that under H/SD conditions, exosomes derived from M1-type macrophages can induce BMSC apoptosis by delivering miR-222 to BMSCs., (© 2021. The Author(s), under exclusive licence to United States and Canadian Academy of Pathology.)

Paraquat (PQ) is a toxic non-selective herbicide. To date, the effect of PQ on memory immune response is still unknown. We investigated the impact of PQ on memory immune response. Adult C57BL/6 mice were subcutaneously injected with 2 mg/kg PQ, 20 mg/kg PQ or vehicle control every three days for two weeks. A single injection of keyhole limpet hemocyanin (KLH) at day four after the initial PQ treatment was used to induce a primary immune response; a second KLH challenge was performed at three months post the first KLH immunization to induce a secondary immune response. In steady state, treatment with 20 mg/kg PQ reduced the level of serum total IgG, but not that of IgM; treatment with 20 mg/kg PQ decreased the number of effector and memory lymphocytes, but not naïve or inactivated lymphocytes. During the primary immune response to KLH, treatment with 20 mg/kg PQ did not influence the proliferation of lymphocytes or expression of co-stimulatory molecules. Instead, treatment with 20 mg/kg PQ increased the apoptosis of lymphocytes at late stage, but not early stage of the primary immune response. During the secondary immune response to KLH, treatment with 20 mg/kg PQ reduced the serum anti-KLH IgG and KLH-responsive CD4 T cells and B cells. Moreover, effector or activated lymphocytes were more sensitive to PQ-induced apoptosis in vitro. Treatment with 2 mg/kg PQ did not impact memory immune response to KLH. Thus, treatment with 20 mg/kg PQ increased apoptosis of late stage effector cells to yield less memory cells and thereafter impair memory immune response, providing a novel understanding of the immunotoxicity of PQ.

Objective To explore the effects of lncRNA ANCR regulating miR-497-5p on vascular lumen formation, apoptosis and PI3K/AKT signaling pathway of gastric cancer cells. Methods Gastric cancer cells were collected and divided into gastric cancer cell (GC) group, gastric cancer cell +lncRNA ANCR-NC (AN) group, gastric cancer cell + lncRNA ANCR overexpressed plasmid (AM) group, gastric cancer cell + lncRNA ANCR siRNA (AI) group, gastric cancer cells + miR-497-5p-NC (MN) group, gastric cancer cells + miR-497-5p siRNA (MI) group, gastric cancer cells +miR-497-5p mimics (MM) group, and gastric cancer cells + lncRNA ANCR siRNA+miR-497-5p mimics (IM) group. Vascular lumen formation was observed by lumen formation assay, cell apoptosis was detected by PI staining method, and protein expression of PI3K and AKT was detected by western blotting. The interaction between lncRNA ANCR and miR-497-5p was confirmed by double luciferase reporting assay. Results Compared with AN group and MN group, the apoptosis rate of AM group and MI group was significantly decreased (P＜0.05), the number of vascular lumen formation and the expression of PI3K and AKT protein were significantly increased (P＜0.05). Compared with AM and MI groups, the apoptosis rate of AI and MM groups was significantly increased (P＜0.05), while the number of vascular lumen formation and the expression of PI3K and AKT protein were significantly decreased (P＜0.05). Compared with AI and MM groups, the apoptosis rate of IM group was significantly increased (P＜0.05), the number of vascular lumen formation and the expression of PI3K and AKT protein were significantly decreased (P＜0.05). The results of double luciferase report showed that transfection of lncRNA ANCR could significantly reduce the luciferase activity of miR-497-5p-3′-UTR-WT (P＜0.05), but had no significant effect on mutant genes (P＞0.05). Conclusion Inhibition of lncRNA ANCR can effectively inhibit the formation of vascular lumen, promote cell apoptosis, and inhibit the expression of PI3K/AKT signaling pathway in gastric cancer cells, which may be related to the targeted activation of miR-497-5p.

Simple Summary: Mammary gland tumors are prevalent in canines, posing significant threats to their health and survival. With the limited efficacy of traditional treatments due to the high heterogeneity of these tumors, there is a growing focus on exploring new therapeutic avenues. Natural Killer cell-based immunotherapy has emerged as a promising approach in anti-tumor treatment, prompting research into optimization strategies. Resveratrol, a natural polyphenol compound, shows potential in regulating Natural Killer cell immune activity. However, the specific impact of Resveratrol-activated Natural Killer cells on canine mammary tumors and their therapeutic potential remain unclear. This study investigated the therapeutic potential of Resveratrol-activated Natural Killer cells in treating canine mammary tumors. Using various assays, including wound healing and flow cytometry, the study examined the impact of Resveratrol-pretreated Natural Killer cells on tumor cells in vitro and in a mouse model. The results demonstrate that Resveratrol enhances Natural Killer cells' ability to induce tumor cell death and inhibit tumor growth, migration, and invasion. Moreover, Resveratrol boosts Natural Killer cell recruitment to other immune cells in the body. Overall, Resveratrol shows promise in enhancing Natural Killer cell-mediated anti-tumor effects, suggesting a potential avenue for optimizing immunotherapy for canine mammary tumors and improving treatment efficacy. In order to explore the therapeutic effect of Resveratrol (Res)-activated Natural Killer (NK) cells on canine mammary tumors, this study employed a range of assays, including wound healing, colony formation, Transwell, flow cytometry, and Western blot experiments, to investigate the impact of Res-pretreated NK cells on canine mammary tumor cells in vitro. Additionally, a tumor-bearing mouse model was utilized to further analyze the therapeutic effects of Res-pretreated NK cells in vivo. The results showed that Res enhances the capacity of NK cells to induce apoptosis, pyroptosis, and ferroptosis in canine breast tumor cells, while also augmenting their influence on the migration, invasion, and epithelial-mesenchymal transition of these cells. Furthermore, pretreatment of NK cells with Res significantly amplified their inhibitory effect on breast tumor growth in vivo and promoted tumor tissue apoptosis. Additionally, Res enhanced the recruitment of NK cells to other immune cells in the body. In summary, Res has been shown to enhance the anti-breast-tumor effect of NK cells both in vitro and in vivo, offering a new avenue for optimizing immunotherapy for canine breast tumors. [ABSTRACT FROM AUTHOR]

Background: Metformin, a first-line antidiabetic drug, has recently been reported with anticancer activities in various cancers; however, the underlying mechanisms remain elusive. The aim of the present study was to investigate the role of cellular FADD-like IL-1β-converting enzyme (FLICE)-inhibitory protein large (c-FLIPL) in metformin-induced anticancer activity in non-small cell lung cancer (NSCLC) in vitro. Materials and methods: Cell viability was measured by MTT assay. Quantitative real-time PCR was carried out to detect the level of mRNA of related genes. The expression of related proteins was detected by Western blot. siRNA was used to silence the expression of targeted proteins. Results: Metformin significantly suppressed proliferation of both A549 and H460 cells in a dose-dependent manner. Mechanistic studies suggested that metformin killed NSCLC cells by inducing apoptotic cell death. Moreover, metformin greatly inhibited c-FLIPL expression and then promoted its degradation. Furthermore, metformin significantly activated Adenosine 5′-monophosphate (AMP)-activated protein kinase (AMPK) and its downstream glycogen synthase kinase 3beta (GSK-3β), block the expression of AMPK, and GSK-3β with siRNA partially reversed metformin-induced cytotoxicity and restored the expression of c-FLIPL in lung cancer cells. Metformin also suppressed the activity of AMPK downstream protein kinase A (PKA), PKA activators, both 8-Br-cAMP and forskolin, greatly increased c-FLIPL expression in NSCLC cells. Conclusion: This study provided evidence that metformin killed NSCLC cells through AMPK/PKA/GSK-3β axis-mediated c-FLIPL degradation. [ABSTRACT FROM AUTHOR]

Background. Human umbilical cord mesenchymal stem cells (UC-MSCs) can regulate the function of immune cells. However, whether and how UC-MSCs can modulate the function of Vγ9Vδ2 T cells has not been fully understood. Methods. The PBMCs or Vγ9Vδ2 T cells were activated and expanded with pamidronate (PAM) and interleukin-2 (IL-2) with or without the presence UC-MSCs. The effects of UC-MSCs on the proliferation, cytokine expression, and cytotoxicity of Vγ9Vδ2 T cells were determined by flow cytometry. The effects of UC-MSCs on Fas-L, TRAIL-expressing Vγ9Vδ2 T cells, and Vγ9Vδ2 T cell apoptosis were determined by flow cytometry. Results. UC-MSCs inhibited Vγ9Vδ2 T cell proliferation in a dose-dependent but cell-contact independent manner. Coculture with UC-MSCs reduced the frequency of IFNγ+ but increased granzyme B+ Vγ9Vδ2 T cells. UC-MSCs inhibited the cytotoxicity of Vγ9Vδ2 T cells against influenza virus H1N1 infected A549 cells and also reduced the frequency of Fas-L+, TRAIL+ Vγ9Vδ2 T cells but failed to modulate the apoptosis of Vγ9Vδ2 T cells. Conclusions. These results indicated that UC-MSCs efficiently suppressed the proliferation and cytotoxicity of Vγ9Vδ2 T cells and modulated their cytokine production. Fas-L and TRAIL were involved in the regulation. Cell contact and apoptosis of Vγ9Vδ2 T cells were not necessary for the inhibition. [ABSTRACT FROM AUTHOR]

The objective of the present study was to evaluate the effects of dietary choline levels on growth performance, antioxidant capacity, innate immunity and hemocyte apoptosis of Litopenaeus vannamei. Six isonitrogenous and isolipidic diets were formulated to contain different choline levels: 2.91 (basal diet), 3.85, 4.67, 6.55, 10.70 and 18.90 g kg−1choline, respectively. The results indicated that shrimp fed diet with 4.67 g kg−1 choline had the highest final body weight (FBW), percent weight gain (PWG), specific growth rate (SGR), feed efficiency (FE), and activities of alkaline phosphatase (AKP) and phenoloxidase (PO) in hemolymph among all treatments. Shrimp fed diet with 18.90 g kg−1 choline exhibited significantly lower crude lipid in hepatopancreas than those fed diets with 2.91, 3.85, 4.67 and 6.55 g kg−1 choline (P < 0.05). The concentration of reactive oxygen species (ROS) and apoptosis rate in hemocytes significantly decreased with the increase of dietary choline levels (P < 0.05). Shrimp fed diets with 6.55, 10.70 and 18.90 g kg−1 choline had significantly higher scavenging ability of hydroxyl radical (SAHR) and total antioxidant capacity (T-AOC) in hemolymph than those fed diet with 2.91 g kg−1 choline (P < 0.05). Dietary choline supplementation down-regulated the expression of genes related to apoptosis such as caspase-1 , caspase-3 , caspase-8 , p53 , and p38MAPK in hemocytes (P < 0.05), while up-regulated the expression of anti-apoptosis gene bcl2 in hemocytes (P < 0.05). Overall, the results of the present study demonstrated that appropriate dietary choline could improve growth performance and feed utilization, enhance antioxidant capacity and innate immunity, and mitigate apoptosis in Litopenaeus vannamei. Moreover, the inhibition of hemocyte apoptosis by dietary choline may be regulated by the p38MAPK-p53 signaling pathway. A plausible mechanism for how choline affects growth performance, antioxidant capacity, and innate immunity, and inhibits hemocyte apoptosis in Litopenaeus vannamei. Solid red arrows indicate promotion and black lines indicate suppression. [Display omitted] • The optimal choline requirement was estimated to be 3.27 g kg−1 for juvenile Litopenaeus vannamei. • Dietary choline could enhance antioxidant effects by a series of enzymatic reactions. • Dietary excessive choline could significantly reduce ROS concentration and apoptotic rate in hemocytes. • Inhibitory effect of dietary choline on hemocyte apoptosis may be regulated by p38MAPK-p53 signaling pathway. [ABSTRACT FROM AUTHOR]

Dendritic cells (DCs) are critical for both innate and adaptive immunity. Meanwhile, nitric oxide (NO) is a member of reactive nitrogen species (RNS) generally considered to play a key role in the bactericidal process in innate immunity against Mycobacterium tuberculosis complex infection. The present study therefore investigated the mechanism of NO production in murine DCs induced by Mycobacterium bovis (M.bovis) and its attenuated strain Bacillus Calmette-Guérin (BCG) infection. The expression of genes Slc7A1, Slc7A2, iNOS, and ArgI essential to NO synthesis was up-regulated in M.bovis /BCG infected DCs. IFN-γ addition further increased, while the iNOS inhibitor L-NMMA significantly inhibited their expression. Accordingly, the end products of arginine metabolism, NO and urea, were found to be significantly increased. In addition, BCG induced significantly higher levels of apoptosis in DCs compared to M.bovis shown by higher levels of DNA fragmentation using flow cytometry and release of mitochondrial Cytochrome C, and up-regulation of the genes caspase-3, caspase-8 , caspase-9 and dffa critical to apoptosis by qRT-PCR detection and western blot analysis. Furthermore, IFN-γ increased, but L-NMMA decreased apoptosis of M.bovis /BCG infected DCs. In addition, mycobacterial intracellular survival was significantly reduced by IFN-γ treatment in BCG infected DCs, while slightly increased by L-NMMA treatment. Taken altogether, our data show that NO synthesis was differentially increased and associated with apoptosis in M.bovis /BCG infected DCs. These findings may significantly contribute to elucidate the pathogenesis of M.bovis. • The bacilli infection significantly increased arginine metabolism in DCs. • BCG induced higher NO production than M.bovis in DCs. • BCG induced higher levels of apoptosis in DCs than M.bovis associated with NO. • BCG survival in DCs was in agreement with the trend of apoptosis in response to NO. [ABSTRACT FROM AUTHOR]

This study was conducted to obtain the optimal dietary lipid requirement and evaluate the differential regulatory effects of optimal or excessive dietary lipid levels on growth performance, lipid metabolism and physiological responses including oxidative stress (OS) and endoplasmic reticulum stress (ERS) of juvenile black seabream (Acanthopagrus schlegelii) (initial weight 2.08 ± 0.01 g). Six isonitrogenous experimental diets were formulated with graded levels of lipid: 6.87% (D1), 11.17% (D2), 14.35% (D3), 18.89% (D4), 23.93% (D5) and 26.94% (D6), respectively. Results indicated that fish fed with the D2 diet showed significantly higher values of final weight (FW), weight gain (WG) and specific growth rate (SGR) than those fed with the other diets, except for D3 group. In fish fed with the diets containing 11.17% and 14.35% (D2 and D3 groups) had the significantly higher contents of high density lipoprotein cholesterol (HDL-C) than other treatments, but showed markedly low concentrations of low density lipoprotein cholesterol (LDL-C). The contents of cholesterol (TC), triglyceride (TG), aspartate aminotransferase (AST) and alanine transaminase (ALT) in serum increased with the increasing of dietary lipid levels, except for the contents of AST and ALT in D1 group. Likewise, the results of hepatic paraffin section indicated that fish fed the dietary lipid levels of 18.89% or beyond (D4, D5 and D6) increased vacuolar fat drops and induced hepatic fat pathological changes. The mRNA expression level and protein concentration of sterol regulatory element-binding protein-1(srebp-1) were significantly up-regulated with the increasing of dietary lipid levels. However, the mRNA expression levels and protein concentrations of peroxisome proliferator-activated receptor alpha (pparα) and silent information regulator 1 (sirt1) significantly activated by fish fed with the D2 diet. Additionally, when fish fed with excessive dietary lipid (over 18.89%) could result in various responses related to OS and ERS. The key marker of OS malonaldehyde (MDA) was significantly increased with the increasing of dietary lipid levels being highest in the D6 group. A contrary pattern was found for total antioxidant capacity, which showed significantly higher activity in the D2 group. All parameters related to ERS increased with the increasing of dietary lipid levels and, hence, triggering inflammation and apoptosis by up-regulating the expression levels of key genes including nuclear factor kappa B (nf-κb) and c-Jun N-terminal kinase (jnk). Overall, based on WG, the optimal dietary lipid requirement of juvenile A. schlegelii is 12.82% by quadratic curve model analysis. When dietary lipid level exceeded 18.89%, excessive lipid could reduce growth performance, cause hepatic fat pathological changes, induce lipid deposition by modulating Sirt1/Srebp-1/Pparɑ pathways, lead to OS and ERS and, hence, triggering hepatic inflammation and apoptosis. These findings provide further insight and understanding of the regulatory effects on growth, lipid metabolism, physiological stress response (including OS and ERS) of A. schlegelii fed with optimal or excessive dietary lipid levels • The optimal dietary lipid requirement of juvenile A. schlegelii is 12.82%. • Optimal lipid diet could maintain normal physiological functions of A. schlegelii. • Dietary lipid levels containing 18.89% or beyond had adverse effect on growth. • Excessive lipid diet induced lipid deposition by modulating Sirt1/Pparα/Srebp1pathway. • Excessive lipid diet caused stress responses including OS and ERS. [ABSTRACT FROM AUTHOR]