Immuno-modulatory and cellular antioxidant activities of κ-selenocarrageenan in combination with Epirubicin in H22 hepatoma-bearing mice

The Antitumor Potential of λ-Carrageenan Oligosaccharides on Gastric Carcinoma by Immunomodulation

Gastric carcinoma is a frequently detected malignancy worldwide, while its mainstream drugs usually result in some adverse reactions, including immunosuppression. λ-carrageenan oligosaccharides (COS) have attracted increasing attention as potential anticancer agents due to their ability to enhance immune function. Our current work assessed the antitumor mechanism of λ-COS using BGC-823 cells. Our findings indicated that λ-COS alone did not have a significant impact on BGC-823 cells in vitro; however, it was effective in inhibiting tumor growth in vivo. When THP-1 cells were pre-incubated with λ-COS and used to condition the medium, BGC-823 cells in vitro displayed a concentration-dependent induction of cell apoptosis, nuclear damage, and the collapse of mitochondrial transmembrane potential. These findings suggested that the antineoplastic effect of λ-COS was primarily due to its immunoenhancement property. Treatment with λ-COS was found to significantly enhance the phagocytic capability of macrophages, increase the secretion of TNF-α and IFN-γ, and improve the indexes of spleen and thymus in BALB/c mice. In addition, λ-COS was found to inhibit the growth of BGC-823-derived tumors in vitro by activating the Par-4 signaling pathway, which may be stimulated by the combination of TNF-α and IFN-γ. When used in combination with 5-FU, λ-COS demonstrated enhanced anti-gastric carcinoma activity and improved the immunosuppression induced by 5-FU alone. These findings suggested that λ-COS could be used as an immune-modulating agent for chemotherapy.

Epirubicin toxicity in rat's ovary and uterus: A protective role of 3-Indolepropionic acid supplementation

The "anthracycline, Epirubicin (EPI)," in managing breast cancer, is highly cytotoxic. Tryptophan-derived 3-indolepropionic acid (3-IPA) decreases oxidative damage, and its prospect of alleviating EPI-induced cytotoxicity was examined in rats' hypothalamus-ovary-uterus axis. Female rats: Control, EPI (2.5 mg/kg), 3-IPA alone (40 mg/kg), EPI+3-IPA (2.5 mg/kg + 20 mg/kg), EPI + 3-IPA2 (2.5 mg/kg + 40 mg/kg) were treated for 28 days. Subsequently, reproductive hormones, oxidative and inflammatory stress biomarkers, and tissue histology were examined. 3-IPA prevented EPI-induced decreases in the follicle-stimulating hormone, estradiol, progesterone and prolactin levels. EPI-mediated reduction in antioxidant enzymes, reduced glutathione and total sulfhydryl groups were partially counteracted by 3-IPA co-treatment. Increased oxidative and inflammatory stress biomarkers caused by treatment with EPI alone were lessened by 3-IPA co-treatment. Also, 3-IPA reduced histological damage in the examined tissues. Conclusively, 3-IPA ameliorated biochemical markers and tissue injury caused by EPI treatment alone via an antioxidative and anti-inflammatory mechanism while stabilising serum hormone dynamics.

κ-Selenocarrageenan Oligosaccharides Prepared by Deep-Sea Enzyme Alleviate Inflammatory Responses and Modulate Gut Microbiota in Ulcerative Colitis Mice

κ-Selenocarrageenan (KSC) is an organic selenium (Se) polysaccharide. There has been no report of an enzyme that can degrade κ-selenocarrageenan to κ-selenocarrageenan oligosaccharides (KSCOs). This study explored an enzyme, κ-selenocarrageenase (SeCar), from deep-sea bacteria and produced heterologously in Escherichia coli, which degraded KSC to KSCOs. Chemical and spectroscopic analyses demonstrated that purified KSCOs in hydrolysates were composed mainly of selenium-galactobiose. Organic selenium foods through dietary supplementation could help regulate inflammatory bowel diseases (IBD). This study discussed the effects of KSCOs on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in C57BL/6 mice. The results showed that KSCOs alleviated the symptoms of UC and suppressed colonic inflammation by reducing the activity of myeloperoxidase (MPO) and regulating the unbalanced secretion of inflammatory cytokines (tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-10). Furthermore, KSCOs treatment regulated the composition of gut microbiota, enriched the genera Bifidobacterium, Lachnospiraceae_NK4A136_group and Ruminococcus and inhibited Dubosiella, Turicibacter and Romboutsia. These findings proved that KSCOs obtained by enzymatic degradation could be utilized to prevent or treat UC.

Murine hepatoma treatment with mature dendritic cells stimulated by Trichinella spiralis excretory/secretory products

Excretory/Secretory Products (ESPs) of the nematode Trichinella spiralis contain antitumor-active substances that inhibit tumor growth. Mature dendritic cells (DCs) play a critical role in the antitumor immunity of the organism. As pathogen-derived products, it ought to be discussed whether T. spiralis ESPs will reduce the antitumor effect of mature DCs from the host before it is applied to patients' tumors. Therefore, the aim of this work was to evaluate the immunological effect of DCs stimulated by T. spiralis ESPs in H22 tumor-bearing mice. H22 tumor model mice in this study were randomly divided into four groups according to the treatment: PBS control group, ESP group, DCs group, and DCs stimulated with T. spiralis ESP (ESP+DCs group). The antitumor effect was evaluated by tumor inhibition rate and cytokine detection using ELISA. The results showed significant inhibition in tumor growth in the ESP+DCs, DCs and ESP groups when compared with the PBS control group (p < 0.01, p < 0.01, and p < 0.05, respectively). However, no significant difference was observed on tumor inhibition rates between the ESP+DCs and DCs groups. The decrease in IL-4, IL-6, and IL-10, and the increase in IFN-γ between the DCs and ESP+DCs groups were also not significant. Therefore, DCs stimulated by ESP did not reduce the antitumor effect of mature DCs, which demonstrated that the T. spiralis ESP would not affect the antitumor effect of mature DCs by modulating the immune response of the host, and that ESPs are safe in antitumor immunology when applied in a tumor model mice.

Signaling pathway underlying splenocytes activation by polysaccharides from Atractylodis macrocephalae Koidz

Previous study demonstrated that total polysaccharides isolated from Atractylodis macrocephalae Koidz. (RAMPtp) were effective to eliminate intramammary infection in cows. The present study was designed to investigate the immunomodulatory activity of RAMPtp in mouse splenocytes. Splenocyte proliferation, natural killer (NK) cytotoxicity, productions of NO and cytokines, transcription factor activity as well as the signal pathways and receptor were examined. The results showed that RAMPtp significantly promoted splenocyte proliferation and made the cells enter S and G2/M phases, increased ratios of T/B cells, boosted NK cytotoxicity, enhanced transcriptional activities of nuclear factor of activated T cells (NFAT), nuclear factor κB (NF-κB) and activator protein 1 (AP-1), and stimulated secretions of NO, immunoglobulin G (IgG) and multiple cytokine families (IL-1α, IL-1β, IL-2, IL-3, IL-4, IL-6, IL-10, IL-12p40, IL-12p70, IL-13, IFN-γ, TNF-α, G-CSF, GM-CSF, KC, MIP-1α, MIP-1β, RANTES and Eotaxin). In addition, all the specific inhibitors against the mitogen-activated protein kinases (MAPKs) and NF-κB significantly suppressed the IL-6 production induced by RAMPtp. Moreover, splenocytes from Toll-like receptor 4 (TLR4) deficient mouse responded equally to RAMPtp stimulation as the wild-type. Therefore, RAMPtp might induce splenocytes activation at least in part via the TLR4-independent MAPKs and NF-κB signaling pathways. The present results would be useful to further understand the immunomodulatory mechanisms of RAMPtp in elimination of intramammary infection in cows.

Structural Characterization and Antitumor Activity of Polysaccharides from Kaempferia galanga L

The water-soluble polysaccharides from Kaempferia galanga L. (KGPs) were extracted and purified, and their structural characteristics and antitumor activity were further investigated. The UV spectrum, high-performance gel permeation chromatography (HPGPC), Fourier-transform infrared spectroscopy (FTIR), and ion chromatography (IC) were employed to evaluate the structural characteristics, and H22 tumor-bearing mice model was established to demonstrate the antitumor activity. Physicochemical analysis and UV spectrum results showed that the proportions of total sugar, protein, and uronic acid in KGPs were 85.23%, 0.54%, and 24.17%, respectively. HPGPC, FTIR, and IC indicated that KGPs were acidic polysaccharides with skeletal modes of pyranose rings and mainly composed of arabinose and galactose with the average molecular weight of 8.5 × 105 Da. The in vivo antitumor experiments showed that KGPs could effectively protect the thymus and spleen of tumor-bearing mice from solid tumors and enhance the immunoregulatory ability of CD4+ T cells, the cytotoxic effects of CD8+ T cells and NK cells, and finally resulting in the inhibitory effects on H22 solid tumors. This study provided a theoretical foundation for the practical application of KGPs in food and medical industries.

A novel mechanism of tumor-induced thymic atrophy in mice bearing H22 hepatocellular carcinoma

Background

Thymic atrophy was discovered in tumor-bearing mice in recent years.

Methods

Flow cytometry was carried out including Annexin V-FITC/PI double staining, PI staining, Terminal dUTP nick-end labeling, CD3-FITC/CD19-PE and CD8-FITC/CD4-PE double staining. Enzyme-linked immunosorbent assay and polymerase chain reaction were also investigated.

Results

According to our experiments, we demonstrated that no signs of apoptosis in thymocytes were found in H22-bearing mice, while the proportions of CD4⁺ T cells and CD8⁺ T cells in thymuses were remarkably increased, the opposite tendency was found in peripheral bloods, and only CD3⁺CD8⁺ T cells were discovered in H22 solid tumors. We further discovered that the level of thymosin alpha 1 (Tα1) and the expression of Wnt4 in thymus of H22-bearing mice were significantly improved than control, which indicated the active proliferation and differentiation of thymocytes. Our study revealed that CD8⁺ T cells could not effectively eliminate H22 cells independently when CD4⁺ T cells were suppressed by tumors, while the body would only enhance the differentiation and maturation of T cells in thymuses and release them to solid tumor to reinforce antitumor immunocompetence, leading to a vicious cycle which finally led to thymic atrophy.

Conclusion

Our data propose a novel mechanism of tumor-induced thymic atrophy regulated by abnormal immunoreaction and may provide new ideas for the immunotherapy of tumors.