Preparation of Vanillin-Taurine Antioxidant Compound, Characterization, and Evaluation for Improving the Post-Harvest Quality of Litchi.

Litchi's post-harvest pericarp browning is one of the main constraints that drastically affect its visual attributes and market potential. Therefore, the vanillin-taurine Schiff base (VTSB) compound prepared from natural compounds of vanillin and taurine exhibited higher DPPH-radical-scavenging invitro antioxidant activity than vanillin. VTSB first-time report to mitigate the postharvest browning of litchi fruit. In this study, litchi fruits were dipped in 0.3 mM (based on pre-experiment) VTSB solution and stored at 25 ± 1 °C for six days to examine their effects on browning and postharvest quality. Fruit treated with VTSB had lower levels of browning degree (BD), browning index (BI), weight loss, soluble quinone (SQ), relative electrolyte leakage (REL), and malondialdehyde (MDA) than control fruit. Additionally, total anthocyanins and phenolic concentrations, Total soluble solids (TSS), and 2,2-diphenyl-1-picrylhydrazyl-free radical scavenging activity (DPPH-RSA) were preserved higher in VTSB-treated litchi fruit. The levels of Ascorbate peroxidase (APX), Superoxide dismutase (SOD), and Catalase (CAT) were higher in treated fruit, whereas polyphenol oxidase (PPO) and Peroxidase (POD) were decreased during the postharvest period. This study suggested that VTSB would be very useful for different post-harvest problems in the fruit and vegetable industry.

Corrigendum: Dihydroartemisinin Induces Growth Arrest and Overcomes Dexamethasone Resistance in Multiple Myeloma.

[This corrects the article DOI: 10.3389/fonc.2020.00767.].

Steroid 5α-Reductase Type I Induces Cell Viability and Migration via Nuclear Factor-κB/Vascular Endothelial Growth Factor Signaling Pathway in Colorectal Cancer.

Colorectal cancer (CRC) is a common malignant tumor of the digestive system. Steroid 5α-reductase type I (SRD5A1), as an important part of the steroid metabolism, converts testosterone to dihydrotestosterone and regulates sex hormone levels, which accommodates tumor occurrence or development. However, the underlying molecular mechanism of SRD5A1 in CRC remains unclear. We compared SRD5A1 expression in CRC tissues with normal controls by immunohistochemistry and found that elevated SRD5A1 in CRC was relevant for poor patient prognosis. Furthermore, inducible downregulation of SRD5A1 by small hairpin RNA reduced cell viability, promoted cell cycle arrest, and induced cell apoptosis and cellular senescence of CRC cells, as well as attenuated cell migration ability. In the following experiments, we used dutasteride (an inhibitor of SRD5A1/2) to explore its inhibitory effect on the biological processes of CRC cells, as mentioned earlier. Further mechanism study demonstrated that the repression of SRD5A1 abolished the expression of p65 and vascular endothelial growth factor, suggesting that SRD5A1 might regulate cell viability and migration through nuclear factor-κB/vascular endothelial growth factor signaling pathway. Collectively, these findings implicate SRD5A1 acting as a novel biomarker for CRC diagnosis and prognosis and provide compelling evidence for the future evaluation of dutasteride as a promising candidate for CRC treatment.

Dihydroartemisinin Induces Growth Arrest and Overcomes Dexamethasone Resistance in Multiple Myeloma.

The discovery of artemisinin (ART) for malaria treatment won the 2015 Nobel Prize in Medicine, which inspired the rediscovery and development of ART for the treatment of other diseases including cancer. In this study, we investigated the potential therapeutic effect of ART and dihydroartemisinin (DHA) on multiple myeloma (MM) cells including primary MM cells and in 5TMM3VT mouse model. Both in vitro and in vivo experiments showed that DHA might be a more promising anti-MM agent with significantly improved efficacy compared to ART. Mechanistic analyses suggested that DHA activated the mitochondrial apoptotic pathway by interacting with ferrous (Fe2+) ions and oxygen to produce reactive oxygen species (ROS). Intriguingly, DHA could reverse the upregulated expression of B-cell lymphoma 2 (Bcl-2) protein, a typical mitochondrial apoptotic marker, induced by dexamethasone (Dexa) in MM. We further demonstrated that DHA treatment could overcome Dexa resistance and enhance Dexa efficacy in MM. Additionally, DHA combined with Dexa resulted in increased ROS production and cytochrome C translocation from the mitochondria to the cytoplasm, resulting in alterations to the mitochondrial membrane potential and caspase-mediated apoptosis. In summary, our study demonstrated that DHA was superior to ART in MM treatment and overcame Dexa resistance both in vitro and in vivo, providing a promising therapeutic strategy for MM therapy.

Modified Pulsatillae decoction inhibits DSS-induced ulcerative colitis in vitro and in vivo via IL-6/STAT3 pathway.

BACKGROUND: Ulcerative colitis (UC) is a chronic inflammatory disorder of the colon and rectum, which is positively correlated with the occurrence of IBD-related colorectal cancer (IBD-CRC). Conventional therapies based on drugs such as corticosteroids, mesalamine, and immunosuppression have serious side effects. Pulsatillae decoction (PD) served as a classical prescription for the treatment of colitis in China, has been shown to exert prominent curative effects and good safety. Based on clinical experience and our amelioration, we added an extra herb into this classical prescription, but its therapeutic effect on UC and the underlying mechanism are still unclear. RESULTS: We first found the curative effect of modified PD on dextran sodium sulfate (DSS)-incubated NCM460 cells. Then C57BL/6 mice were administered DSS to induce UC to evaluate the therapeutic of modified PD. The results showed that modified PD alleviated the inflammatory injury, manifested in body weight, colon length, and disease activity index, with histological analysis of colon injury. Transcriptomic sequencing indicated that modified PD treatment downregulated the IL-6/STAT3 signaling pathway, and reduced the levels of p-NF-κB, IL-1ß and NLRP3, which were confirmed by western blot. CONCLUSIONS: Collectively, our results indict that modified PD could efficiently relieve clinical signs and inflammatory mediators of UC, providing evidence of the anti-colitis effect of modified PD, which might provide novel strategies for therapeutic intervention in UC, which may be applied to the prevention of IBD-CRC.

Bioactive Compounds from Abelmoschus manihot L. Alleviate the Progression of Multiple Myeloma in Mouse Model and Improve Bone Marrow Microenvironment.

PURPOSE: Abelmoschus manihot (L.) Medik. (Malvaceae) derived Huangkui capsules (HKC) represent a traditional Chinese medicine that has been widely applied to the clinical therapy of kidney and inflammatory diseases. The present study aimed to determine the potential therapeutic effects and underlying mechanisms of the ingredients on Multiple Myeloma (MM), an incurable disease that exhibits malignant plasma cell clonal expansion in the bone marrow. METHODS: A 5TMM3VT syngeneic MM-prone model was established and treated with HKC. Murine pre-osteoblast MC3T3-E1 and pre-osteoclast Raw264.7 cells were treated with nine flavonoid compounds extracted from the flowers of Abelmoschus manihot. MC3T3-E1 and Raw264.7 cells were then examined by alizarin red staining and tartrate-resistant acid phosphatase activity staining, respectively. The proliferation of two human MM cells (ARP1, H929) was examined by performing an MTT assay following treatment with flavonoid compounds. Additionally, the cell cycle was analyzed via staining and flow cytometry. The differential expressions of certain proteins were detected via Western blotting, transcriptomic RNA-sequencing as well as RT-qPCR. RESULTS: The results revealed that MM-prone animals appeared to be protected following HKC treatment, as evidenced by a prolonged survival rate. Furthermore, four of the nine flavonoid compounds [Hyperin/Hyperoside, HK-2; Cannabiscitrin, HK-3; 3-O-kaempferol-3-O-acetyl-6-O-(p-coumaroyl)-ß-D-glucopyranoside, HK-11; 8-(2''-pyrrolidione-5''-yl)-quercetin, HK-B10] induced the differentiation of murine pre-osteoblast MC3T3-E1 cells. In addition, two compounds [Isomyricitrin, HK-8; quercetin-8-(2''-pyrrolidione-5"-yl)-3'-O-ß-D-glucopyranosid, HK-E3] suppressed osteoclastogenesis in murine Raw264.7 cells. HK-11 directly inhibited MM cells (ARP1 and H929) proliferation and induced G0/G1 cell cycle arrest, which may have involved the suppressing ß-catenin protein, increasing expressions of IL-6 and TNF-α, as well as activating mature TGF-ß1 and some other metabolic pathways. CONCLUSION: These results of the present study indicated that the bio-active ingredients of HKC exerted protective effects on MM mouse survival through promoting osteoblastogenesis and suppressing osteoclastogenesis, thus improving the bone marrow microenvironment to inhibit MM cell proliferation.