Cyclophosphamide (cy) is a widely used cancer drug. Many researchers have focused on the prevention and alleviation of its side effects, particularly damage to the intestinal mucosal barrier. In this study, we examined the effects of fucoidan, isolated from Acaudina molpadioides, on mice with intestinal mucosal damage induced by cyclophosphamide. Our results showed that fucoidan intervention could relieve injury such as decreasing inflammation and increasing the expression of tight junction proteins, and 50 kDa fucoidan significantly increased the abundance of short chain fatty acid (SCFA) producer Coprococcus, Rikenella, and Butyricicoccus (p < 0.05, p < 0.001, and p < 0.05, respectively) species within the intestinal mucosa compared with the cyclophosphamide group, as determined by 16S rDNA gene high-throughput sequencing. In addition, SCFAs, particularly propionate, butyrate, and total SCFAs, were increased in the feces, and SCFA receptors were upregulated in the small intestine. The protective effects of fucoidan on cyclophosphamide treatment may be associated with gut microflora, and 50 kDa fucoidan had superior effects. Therefore, fucoidan may have applications as an effective supplement to protect against intestinal mucosal barrier damage during chemotherapy.

•Polysaccharide extracted from the ink of Ommastrephes bartrami could protect mouse paneth cells.•OBP treatment could enhance the expression of antimicrobial proteins in paneth cells.•The higher production of antimicrobial proteins in paneth cells was dependent on the highly developed ER structure.Gastrointestinal mucositis (GIM), induced by chemotherapy, is associated with alterations in the function of the intestinal barrier due to the potential damage induced by anti-cancer drugs on the epithelial cells. The Paneth cells, an important epithelial lineage in the intestine, contribute to the innate immunity by releasing antimicrobial proteins onto the mucosal surfaces. Polysaccharide, as a widely used immunomodulatory nutrient, was reported to have an effect of modulating the intestinal immune system. However, the effect of dietary polysaccharides in protecting the Paneth cells from injuries induced by chemotherapy was poorly investigated. In the current study, with a mouse model of cyclophosphamide (Cy)-induced gastrointestinal injury, the polysaccharide extracted from the ink of Ommastrephes bartrami (OBP) were found to protect the mouse Paneth cells from chemotherapeutic injury. Ommastrephes bartrami polysaccharide (OBP) treatment could enhance the mRNA expression of antimicrobial proteins in the Paneth cells, such as lysozyme, Ang4, Defa-5, and sPLA2. The increased production of the microbicidal proteins in the Paneth cells was dependent on the relatively highly developed endoplasmic reticulum (ER) structure but was not dependent on the increase in the quantity of the ER. The Ommastrephes bartrami polysaccharide (OBP) activated the IRE-1 mediated XBP-1s pathway to cope with antimicrobial protein secretion. Our results may have important implications with regard to the role of OBP in chemotherapy-induced Paneth cell injury in intestinal disorders involving inflammation and infection.

Mucositis is a common problem that results from cancer chemotherapy and is a cause of significant morbidity and occasional mortality. Its prevention and successful treatment can significantly enhance the quality of life of patients and improve their survival. Sea cucumber is a traditional aquatic food that has both nutritional and medicinal value. The polysaccharide fucoidan from the sea cucumber (SC-FUC) has various bioactivities. We examined the protective effect of different molecular weights (MWs 50 kDa–500 kDa) of fucoidan from the sea cucumber, Acaudina molpadioides, in a mouse model of cyclophosphamide (Cy)-induced intestinal mucositis. Results showed that the oral administration of SC-FUC markedly reversed Cy-induced damage in the mice. The sea cucumber fucoidan notably increased the ratio of the length of the intestinal villus to the crypt depth and ameliorated the IFN-γ/IL-4 ratio that signifies Th1/Th2 immune balance. Moreover, all the fucoidans in this study enhanced the expression of IgA by accelerating the expression of IL-6 that is probably combined with IL-10. The differing effects of the varied molecular weights of fucoidan may be due to the difference in the efficiency of absorption. This is a novel study on the potential preventive effects of SC-FUC on intestinal mucositis that may be related to the efficiency of its absorption during digestion. Sea cucumber fucoidan (SC-FUC) may be used as a potential food supplement to prevent chemotherapeutic mucositis.

Gastrointestinal mucositis induced by chemotherapy is associated with alterations of intestinal barrier function due to the potential damage induced by anti-cancer drugs on the epithelial cells. Goblet cells, an important epithelial lining in the intestine, contribute to innate immunity by secreting mucin glycoproteins. Employing a mouse model of chemotherapy induced intestinal mucosal immunity injury by cyclophosphamide, we demonstrated for the first time that polysaccharide from the ink of Ommastrephes bartramii (OBP) enhanced Cyto18, which is a mucin expression in goblet cells. The up-regulation of mucins by OBP relied on the augmented quantity of goblet cells, but not on the changes in the ultrastructure of endoplasmic reticulum (ER). Our results may have important implications for enhanced immunopotentiation function of functional OBP on intestinal mucosal immunity against intestinal disorders involving inflammation and infection.

•PaH could be activated by a 470 nm LED light source to produce 1O2.•PaH-PDT demonstrated a significant photocytotoxicity on HT-29 cells.•Early and late apoptotic rate of HT-29 cells increased by PaH-PDT.Palmatine hydrochloride (PaH) is a natural active compound from a traditional Chinese medicine (TCM). The present study aims to evaluate the effect of PaH as a new photosensitizer on colon adenocarcinoma HT-29 cells upon light irradiation. Firstly, the absorption and fluorescence spectra of PaH were measured using a UV–vis spectrophotometer and RF-1500PC spectrophotometer, respectively. Singlet oxygen (1O2) production of PaH was determined using 1, 3-diphenylisobenzofuran (DPBF). Dark toxicity of PaH was estimated using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Cellular uptake of PaH in HT-29 cells was detected at different time intervals. Subellular localization of PaH in HT-29 cells was observed using confocal laser fluorescence microscopy. For photodynamic treatment, HT-29 cells were incubated with PaH and then irradiated by visible light (470 nm) from a LED light source. Photocytotoxicity was investigated 24 h after photodynamic treatment using MTT assay. Cell apoptosis was observed 18 h after photodynamic treatment using a flow cytometry with Annexin V/PI staining. Results showed that PaH has an absorption peak in the visible region from 400 nm to 500 nm and a fluorescence emission peak at 406 nm with an excitation wavelength of 365 nm. PaH was activated by the 470 nm visible light from a LED light source to produce 1O2. Dark toxicity showed that PaH alone treatment had no cytotoxicity to HT-29 cancer cells and NIH-3T3 normal cells after incubation for 24 h. After incubation for 40 min, the cellular uptake of PaH reached to the maximum and PaH was located in mitochondria. Photodynamic treatment of PaH demonstrated a significant photocytotoxicity on HT-29 cells. The rate of cell death increased significantly in a PaH concentration-dependent and light dose-dependent manner. Further evaluation revealed that the early and late apoptotic rate of HT-29 cells increased remarkably up to 21.54% and 5.39% after photodynamic treatment of PaH at the concentration of 5 μM and energy density of 10.8 J/cm2. Our findings demonstrated that PaH as a naturally occurring photosensitizer has potential in photodynamic therapy on colon adenocarcinoma.

•PaH could be activated by a 470 nm LED light source to produce ROS.•PaH-PDT demonstrated a significant photocytotoxicity on MCF-7 cells.•PaH could locate in mitochondria and endoplasmic reticulum of MCF-7 cells.•Early and late apoptotic rate of MCF-7 cells increased by PaH-PDT.Breast cancer is one of the commonest malignant tumors threatening to women. The present study aims to investigate the effect of photodynamic action of palmatine hydrochloride (PaH), a naturally occurring photosensitizer isolated from traditional Chinese medicine (TCM), on apoptosis of breast cancer cells. Firstly, cellular uptake of PaH in MCF-7 cells was measured and the cytotoxicity of PaH itself on breast cancer MCF-7 cells was estimated using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Subcellular localization of PaH in MCF-7 cells was observed using confocal laser scanning microscopy (CLSM). For photodynamic treatment, MCF-7 cells were incubated with PaH and then irradiated by visible light (470 nm) from a LED light source. Photocytotoxicity was investigated 24 h after photodynamic treatment using MTT assay. Cell apoptosis was analyzed 18 h after photodynamic treatment using flow cytometry with Annexin V/PI staining. Nuclear was stained using Hoechst 33342 and observed under a fluorescence microscope. Intracellular production of reactive oxygen species (ROS) was studied by measuring the fluorescence of 2, 7-dichlorofluorescein (DCF) using a flow cytometry. Results showed that PaH treatment alone had no or minimum cytotoxicity to MCF-7 cells after incubation for 24 h in the dark. After incubation for 40 min, the cellular uptake of PaH reached to the maximum, and PaH mainly located in mitochondria and endoplasmic reticulum of MCF-7 cells. Photodynamic treatment of PaH demonstrated a significant photocytotoxicity on MCF-7 cells, induced remarkable cell apoptosis and significantly increased intracellular ROS level. Our findings demonstrated that PaH as a naturally occurring photosensitizer induced cell apoptosis and significantly killed MCF-7 cells.

•Curcumin-mediated photodynamic action could inactivate V. parahaemolyticus cells to undetectable level.•Curcumin as a food additive could be activated by a 470 nm LED light source to produce 1O2.•Curcumin-mediated photodynamic action could degrade the bacterial outer membrane proteins and genetic materials.•Curcumin-mediated photodynamic action had a good decontamination effect against V. parahaemolyticus in oyster.Vibrio parahaemolyticus (V. parahaemolyticus) is currently a major cause of bacterial diarrhoea associated with seafood consumption. The objective of this study was to determine the inactivation effect of curcumin-mediated photodynamic action on V. parahaemolyticus. First of all, V. parahaemolyticus suspended in PBS buffer was irradiated by a visible light from a LED light source with an energy density of 3.6 J/cm2. Colony forming units (CFU) were counted and the viability of V. parahaemolyticus cells was calculated after treatment. Singlet oxygen (1O2) production after photodynamic action of curcumin was evaluated using 9,10-Anthracenediyl-bis (methylene) dimalonic acid (ADMA). Bacterial outer membrane protein was extracted and analyzed using electrophoresis SDS-PAGE. DNA and RNA of V. parahaemolyticus were also extracted and analyzed using agarose gel electrophoresis after photodynamic treatment. Finally, the efficacy of photodynamic action of curcumin was preliminarily evaluated in the decontamination of V. parahaemolyticus in oyster. Results showed that the viability of V. parahaemolyticus was significantly decreased to non-detectable levels over 6.5-log reductions with the curcumin concentration of 10 and 20 μM. Photodynamic action of curcumin significantly increased the singlet oxygen level with the curcumin concentration of 10 μM. Notable damage was found to bacterial outer membrane proteins and genetic materials after photodynamic treatment. Photodynamic action of curcumin reduced the number of V. parahaemolyticus contaminating in oyster to non-detectable level. Our findings demonstrated that photodynamic action of curcumin could be a potentially good method to inactivate Vibrio parahaemolyticus contaminating in oyster.