Anticancer effects of licochalcones: A review of the mechanisms.

Cancer is a disease with a high fatality rate representing a serious threat to human health. Researchers have tried to identify effective anticancer drugs. Licorice is a widely used traditional Chinese medicine with various pharmacological properties, and licorice-derived flavonoids include licochalcones like licochalcone A, licochalcone B, licochalcone C, licochalcone D, licochalcone E, and licochalcone H. By regulating the expression in multiple signaling pathways such as the EGFR/ERK, PI3K/Akt/mTOR, p38/JNK, JAK2/STAT3, MEK/ERK, Wnt/ß-catenin, and MKK4/JNK pathways, and their downstream proteins, licochalcones can activate the mitochondrial apoptosis pathway and death receptor pathway, promote autophagy-related protein expression, inhibit the expression of cell cycle proteins and angiogenesis factors, regulate autophagy and apoptosis, and inhibit the proliferation, migration, and invasion of cancer cells. Among the licochalcones, the largest number of studies examined licochalcone A, far more than other licochalcones. Licochalcone A not only has prominent anticancer effects but also can be used to inhibit the efflux of antineoplastic drugs from cancer cells. Moreover, derivatives of licochalcone A exhibit strong antitumor effects. Currently, most results of the anticancer effects of licochalcones are derived from cell experiments. Thus, more clinical studies are needed to confirm the antineoplastic effects of licochalcones.

Curcumanes E and F, two rare sesquiterpenoids with a dicyclo[3.3.1]nonane moiety, from Curcuma longa and their vasorelaxant activities.

Two new sesquiterpenoids, curcumanes E (1) and F (2), were isolated from the rhizome of Curcuma longa, and their structures and absolute configurations were examined using extensive spectroscopic analyses and ECD calculations. Interestingly, compounds 1 and 2 are diastereoisomers possessing a rare sesquiterpenoid skeleton that has been reported only once before. Both curcumanes E and F exhibit significant vasorelaxant effects against KCl-induced contraction of rat aortic rings, with EC50 values of 5.10 ± 0.79 and 5.58 ± 1.77 µM, respectively. These findings enrich the data concerning this rare type of sesquiterpenoids and further indicate that these rare sesquiterpenoids can effectively reduce blood pressure.

Vasorelaxant effect of curcubisabolanin A isolated from Curcuma longa through the PI3K/Akt/eNOS signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Curcuma longa L. (Zingiberaceae) is a known blood-activating and stasis-removing traditional Chinese medicine and has relevant pharmacological properties. The rhizomes of C. longa have been used for the treatment of cardiovascular disease (CVD) in China. Previous studies have shown that sesquiterpenoids from C. longa have significant vasorelaxant effects, which are closely associated with the prevention and treatment of CVD. AIM OF THE STUDY: To explore the sesquiterpenoids with vasorelaxant effects from C. longa and investigate the underlying mechanisms. MATERIALS AND METHODS: The compound was isolated from C. longa by multiple chromatography technologies. Its structure was determined by extensive spectroscopic analyses, nuclear magnetic resonance (NMR) data calculations, electronic circular dichroism (ECD) data calculations, and optical rotation (OR) data calculations. The vasorelaxant effect of the isolated compound was evaluated by KCl- or phenylephrine (PHE)-inducing contraction of the rat thoracic aortic rings. Endothelial removal and L-NAME pretreatment experiments were used to verify the endothelium-dependent vasorelaxant effect of the isolated compound in rat thoracic aortic rings. NO production was monitored in human umbilical vein endothelial cells (HUVECs). Western blot was carried out in HUVECs to elucidate the potential mechanisms. RESULTS: A new bisabolane-type sesquiterpenoid, curcubisabolanin A [(+)-(1S,7S,9E)-bisabola-2(3),4(15),9(10)-trien-11-ol], was isolated from the rhizomes of C. longa. curcubisabolanin A exhibited endothelium-dependent relaxation on rat thoracic aortic rings, while pre-treatment of intact aortic rings with an eNOS inhibitor (L-NAME) attenuated the vasorelaxant response of curcubisabolanin A. In addition, curcubisabolanin A induced intracellular NO production and significantly increased the levels of phosphorylated PI3K (p-PI3K), phosphorylated Akt (p-Akt), and phosphorylated eNOS (p-eNOS) in HUVECs. LY294002 (a blocker of PI3K) and MK-2206 (a highly selective inhibitor of Akt) significantly decreased these effects of curcubisabolanin A. CONCLUSIONS: These findings demonstrated that the vasorelaxant effect of curcubisabolanin A was partially endothelium-dependent and was related to regulation of NO production in vascular endothelial cells through the PI3K/Akt/eNOS signaling pathway.

[Expression Analysis of miRNA Profiles in Apheresis Platelets during Storage].

OBJECTIVE: To study the expression profiles changes of miRNA in apheresis platelets after 1, 3 and 5 days of storage. METHODS: The apheresis platelets were collected from 20 volunteer blood donors. After mixing fully, the platelets were stored in a shaker with (22±2) ℃ horizontal oscillation. The samples were taken on the 1st, 3rd and 5th day, and used to sequence for miRNAs by DNA nanoball (DNB) sequencing technology, which were named as C_1, C_3 and C_5, respectively. The expression level of platelets miRNA was standardized by transcripts per kilobase million (TPM) algorithm. MiRNAs with P-value < 0.001 and the expression difference of more than two times were considered as significant difference between two groups. The expression of miRNAs was verified by real-time fluorescence quantitative PCR (RT-qPCR). RESULTS: By DNB sequencing, there were 688, 730, and 679 platelet miRNAs expressed in C_1, C_3 and C_5 group, respectively. Cluster analysis showed that the expression profile of miRNAs changed significantly. The expression level of the first 20 high abundance miRNAs was about 4/5 of the total amounts of expressed miRNAs in each group, which the top five miRNAs were miR-21-5p, miR-26a-5p, miR-199a-3p, miR-126-3p, and let-7f-5p. The correlation of high abundance platelet miRNAs among the three groups was high (R2=0.876, R2=0.979, R2=0.937, respectively) and the differences were not statistically significant (P>0.05). Compared with the differential expression of platelet miRNAs with more than 1 000 TPM in the C_3 and C_1 group, there were 6 differentially expressed miRNAs, including 3 up-regulated (miR-146a-5p, miR-379-5p, and miR-486-5p) and 3 down-regulated (miR-652-3p, miR-142-5p, and miR-7-5p). While in the C_5 and C_1 group, there were 4 differentially expressed miRNAs, including 2 up-regulated (miR-146a-5p and let-7b-5p) and 2 down-regulated (miR-30d-5p and miR-142-5p). Compared with the differentially expression of platelet miRNAs between 1-1 000 TPM in the C_3 and C_1 group, there were 133 differentially expressed miRNAs, in which 99 were up-regulated and 34 were down-regulated. While in the C_5 and C_1 group, there were 77 differentially expressed miRNAs, in which 31 were up-regulated and 46 were down-regulated. The six selected differentially expressed miRNAs verified by RT-qPCR were consistent with those of sequencing. CONCLUSION: The expression profiles of platelets miRNAs change significantly among 1, 3, and 5 d of storage in vitro.

MicroRNA expression profiles analysis of apheresis platelets treated with vitamin B2 and ultraviolet-B during storage.

Whether platelet (PLT) microRNA (miRNA) profiles are affected by pathogen reduction technology (PRT) using vitamin B2 and ultraviolet-B (VB2-PRT) remains unclear. Samples from VB2-PRT-treated (experimental group, E_) and untreated (control group, C_) apheresis PLTs were taken on days 1, 3 and 5 of storage, designated as E_1, E_3, E_5, C_1, C_3 and C_5, respectively. The miRNA expression profiles were assessed by DNA Nano Ball (DNB) sequencing technology, and verified by quantitive real-time fluorescence quantitative PCR (qRT-PCR). Compared with the expression profiles of PLT miRNAs, 3895 miRNAs were identified in the E_ groups while 4106 were in the C_ groups. There were 487 significant differentially expressed miRNAs in E_1 vs C_1 group, including 220 upregulated and 287 downregulated, such as miR-146a-5p and let-7b-5p. There were 908 significant differentially expressed miRNAs in E_3 vs C_3 group, including 297 upregulated and 611 downregulated, such as miR-142-5p and miR-7-5p. There were 229 significant differentially expressed miRNAs in E_5 vs C_5 group, including 80 upregulated and 149 downregulated, such as miR-3529-3p and miR-451a. These differentially expressed miRNAs had been suggested to have functional roles in energy homeostasis, cell communication, proliferation, migration and apoptosis. GO analysis showed a significant enrichmen in relevant biological process categories as receptor activity, signal transduction, cell transport, motility and chemotaxis. The significantly enriched KEGG pathway of predicted target genes was Glycosaminoglycan biosynthesis in E_ vs C_ groups. These new observation could provide insights on the understanding of change of miRNA profiles of PLT treated with VB2-PRT.

[Analysis of miRNA-326's action on its target gene BCL-XL].

OBJECTIVE: To analyze the action of miRNA-326 on its target gene BCL-XL and the molecular mechanism of platelet apoptosis regulated by miRNAs. METHODS: Dual-luciferase vectors containing respectively the wild-type and mutant 3'-untranslated region (3'UTR) fragments of the BCL-XL gene were constructed with firefly and renilla luciferases and transfected into 293T cells. Relative fluorescence intensities of the transfected cells were measured. RESULTS: Dual-luciferase reporter gene vectors for PsiCHECK- BCL-XL -3'UTR-WT (wild-type) and PsiCHECK- BCL-XL -3' UTR-MT (variant) were respectively constructed. Relative fluorescence intensities of the 293T cells co-transfected by miRNA-326 and PsiCHECK- BCL-XL -3'UTR-WT plasmid were significantly lower compared with the control group (co-transfected by a miRNA-326 negative sequence and PsiCHECK- BCL-XL -3' UTR-WT plasmid) ( P = 0.034). The relative fluorescence intensity was also significantly reduced in cells co-transfected by miRNA-326 and PsiCHECK- BCL-XL -3' UTR-WT plasmid compared with the mutant control group co-transfected by miRNA-326 and PsiCHECK- BCL-XL -3'UTR-MT plasmid (P = 0.022). CONCLUSION: miRNA-326 may participate in the regulation of platelet apoptosis by acting on the 3'-UTR of the BCL-XL gene.

Seven pairs of new enantiomeric sesquiterpenoids from Curcuma phaeocaulis.

Seven pairs of new enantiomeric sesquiterpenoids, (+)/(-)-phaeocauline A - G [(+)/(-)-1-7], were isolated from the rhizomes of Curcuma phaeocaulis by chiral HPLC separation. Their structures, including absolute configurations, were determined by spectroscopic analyses and ECD data. The isolates were assessed for vasorelaxant, anti-platelet aggregative, and neuroprotective activities. Enantiomers (+)-1 and (-)-1 showed similar activity against abnormal platelet aggregation induced by arachidonic acid, while their C-4 epimers (+)-2 and (-)-2 were inactive, which indicated that those effects were stereoselective, but not enantioselective. Compounds (+)/(-)-3-5 exhibited vasorelaxant effects against KCl-induced contraction of rat aortic rings.

Curcumane C and (±)-curcumane D, an unusual seco-cadinane sesquiterpenoid and a pair of unusual nor-bisabolane enantiomers with significant vasorelaxant activity from Curcuma longa.

A new seco-cadinane sesquiterpenoid (curcumane C, 1) and a pair of new nor-bisabolene enantiomers [(+)- and (-)-curcumane D, 2a and 2b] were isolated from C. longa. Compound 1 possesses an unusual 4,5-seco-cadinane skeleton with a tetrahydrophthalide moiety, while 2a and 2b contain an unusual 15-nor-bisabolene skeleton with a chromone core. All compounds exhibited significant vasorelaxant effects against KCl-induced contraction of rat aortic rings. Compound 1 also exhibited a vasorelaxant effect against phenylephrine-induced contraction of rat aortic rings. Meanwhile, compound 1 showed a stronger vasorelaxant effect in endothelium-intact rat aortic rings compared with endothelium-denuded rat aortic rings, indicating that vasodilation by 1 involved both endothelium-dependent and endothelium-independent pathways. Furthermore, compound 1 increased the NO content in human umbilical vein endothelial cells and its vasorelaxant effect could be attenuated by treatment with L-NAME, an endothelium NO synthase inhibitor. Thus, the underlying vasodilatory mechanisms of 1 may be mediated via abrogation of extracellular Ca2+ influx and regulation of NO release in vascular endothelial cells.

Lethal Encephalitis in Seals with Japanese Encephalitis Virus Infection, China, 2017.

We isolated Japanese encephalitis virus (JEV) from brain samples of 2 seals with lethal encephalitis at Weihai Aquarium, Weihai, China, in 2017. We confirmed our findings by immunohistochemical staining and electron microscopy. Phylogenetic analysis showed this virus was genotype I. Our findings suggest that JEV might disseminate though infected zoo animals.

Photoredox/Cobalt-Catalyzed Phosphinyloxy Radical Addition/Cyclization Cascade: Synthesis of Phosphaisocoumarins.

A novel visible-light photoredox-catalyzed phosphinyloxy radical addition/cyclization cascade of arylphosphinic acids or arylphosphonic acid monoesters with alkynes has been developed, which provides an efficient and practical access to various phosphaisocoumarins by using a dual catalytic system containing an acridinium photosensitizer and a cobaloxime proton-reducing catalyst [Co(dmgH)2]PyCl at ambient temperature. This method has advantages of a broad substrate scope, mild condition, as well as no sacrificial oxidant.

Curcumanes A and B, Two Bicyclic Sesquiterpenoids with Significant Vasorelaxant Activity from Curcuma longa.

Two novel sesquiterpenoids, curcumanes A (1) and B (2), possessing unprecedented skeletons with a dicyclo[3.2.1]octane and a dicyclo[3.3.1]nonane moiety, respectively, were isolated from Curcuma longa. Both of them had remarkable vasorelaxant activity on rat aorta via blocking extracellular Ca2+ influx through VDCCs and ROCCs. The activity of 1 was endothelium-independent, while that of 2 was endothelium-dependent. Compound 2 also prolonged APTT and TT to inhibit blood coagulation.

A Duplex Real-Time PCR Assay for the Simultaneous Detection of Porcine Circovirus 2 and Circovirus 3.

Porcine circoviruses (PCV) include PCV1, PCV2, and the new-emerging PCV3. PCV2 is pathogenic to pigs, but the pathogenicity of PCV3 in pigs is debatable. Recently, there have been frequent reports of PCV2 and PCV3 co-infections in clinical samples. Thus, it would be practical to develop a duplex PCR method to detect PCV2 and PCV3 simultaneously. In this study, specific primers and probes were designed to target PCV2 cap and PCV3 rep genes. A duplex real-time PCR method was then developed to detect the two viruses. The assay was found to be highly specific, sensitive, and reproducible for PCV2/3 without cross-reactions with other swine pathogens. The sensitivity of this assay was 2.9 copies for the PCV2 plasmid and 22.5 copies for the PCV3 plasmid. The established assay was then used to detect PCV2/3 infection in 340 clinical samples collected in the first half of 2017. The results showed that the co-infection rate of PCV2/3 in the samples was 27.6%. Our study provides an important tool that can be used to perform urgently needed surveys for the two porcine circoviruses to evaluate their impact on the swine industry.

Whole genome characterization of a novel porcine reproductive and respiratory syndrome virus 1 isolate: Genetic evidence for recombination between Amervac vaccine and circulating strains in mainland China.

Genotype 1 porcine reproductive and respiratory syndrome virus (PRRSV 1) have been continuously isolated in China in recent years. Complete genome sequences of these isolates are important to investigate the prevalence and evolution of Chinese PRRSV 1. Herein, we describe the isolation of a novel PRRSV 1 isolate, denominated HLJB1, in the Heilongjiang province of China. Complete genome sequencing of HLJB1 showed that it shares 90.66% and 58.21% nucleotide identities with PRRSV 1 and 2 prototypic strains Lelystad virus and ATCC VR-2332, respectively. HLJB1 has a unique 5-amino-acid insertion in nsp2, which has never been described in other PRRSV 1 isolates. Whole genome-based phylogenetic analysis revealed that all Chinese PRRSV 1 isolates are clustered in pan-European subtype 1 and can be divided into four subgroups. HLJB1 resides in the subgroup of BJEU06-1-like isolates but is also closely related to the Amervac-like isolates. Additionally, recombination analyses suggested that HLJB1 is a recombinant from the Amervac vaccine and the BJEU06-1 isolate. To our best knowledge, our results provide the first genetic evidence for recombination between Amervac vaccine and circulating strains. These findings are also beneficial for studying the origin and evolution of PRRSV 1 in China.

Visible-Light-Driven Aza-ortho-quinone Methide Generation for the Synthesis of Indoles in a Multicomponent Reaction.

A visible-light-driven radical-mediated strategy for the in situ generation of aza-ortho-quinone methides from 2-vinyl-substituted anilines and alkyl radical precursors is described. This process enables an efficient multicomponent reaction of 2-vinylanilines, halides, and sulfur ylides, and has a wide substrate scope and good functional group tolerance. Treatment of the cycloaddition products with a base leads to densely functionalized indoles in a single-flask operation.

Assessment and sources of heavy metals in surface sediments of Miyun Reservoir, Beijing.

Heavy metals concentrations in surface sediments from Miyun Reservoir were determined to evaluate the pollution and identify the sources. The average content of metals in sediments from Miyun Reservoir followed the order Al>Fe>Ti>Mn>V>Zn>Cr>Ni>Cu>Pb>As>Cd>Hg, and the most mean values were lower than the globe average shale. Heavy metals concentrations at the inflow area of Baihe were higher than those at the inflow area of Chaohe. Heavy metals pollution assessment was carried out by factor enrichment (EF), geoaccumulation index (I(geo)), and potential ecological risk (RI). The EF values for all heavy metals except Hg, Cd, and Cr at several sites were lower than 3, suggesting low anthropogenic impact on the metals level. The I(geo) values of Pb indicated that half of the sites were unpolluted to moderately polluted and mainly located in the Baihe area of the reservoir. The RI showed that heavy metals of Miyun Reservoir were low potential risk, however, Hg approached or belonged to moderate ecological risk at sites of M5, M7, and M13. Correlation analysis and principal component suggested that Ni, Cu, V, Zn, Mn, Cr, Ti, and Pb were derived from soil erosion in upper reaches of the reservoir, while Fe, Cd, Hg, As, and partial Pb originated from anthropogenic sources, particularly industrial mining and gold tailings.

Emergence of fatal PRRSV variants: unparalleled outbreaks of atypical PRRS in China and molecular dissection of the unique hallmark.

Porcine reproductive and respiratory syndrome (PRRS) is a severe viral disease in pigs, causing great economic losses worldwide each year. The causative agent of the disease, PRRS virus (PRRSV), is a member of the family Arteriviridae. Here we report our investigation of the unparalleled large-scale outbreaks of an originally unknown, but so-called "high fever" disease in China in 2006 with the essence of PRRS, which spread to more than 10 provinces (autonomous cities or regions) and affected over 2,000,000 pigs with about 400,000 fatal cases. Different from the typical PRRS, numerous adult sows were also infected by the "high fever" disease. This atypical PRRS pandemic was initially identified as a hog cholera-like disease manifesting neurological symptoms (e.g., shivering), high fever (40-42 degrees C), erythematous blanching rash, etc. Autopsies combined with immunological analyses clearly showed that multiple organs were infected by highly pathogenic PRRSVs with severe pathological changes observed. Whole-genome analysis of the isolated viruses revealed that these PRRSV isolates are grouped into Type II and are highly homologous to HB-1, a Chinese strain of PRRSV (96.5% nucleotide identity). More importantly, we observed a unique molecular hallmark in these viral isolates, namely a discontinuous deletion of 30 amino acids in nonstructural protein 2 (NSP2). Taken together, this is the first comprehensive report documenting the 2006 epidemic of atypical PRRS outbreak in China and identifying the 30 amino-acid deletion in NSP2, a novel determining factor for virulence which may be implicated in the high pathogenicity of PRRSV, and will stimulate further study by using the infectious cDNA clone technique.

Effects of epidermal growth factor on the growth of human gastric cancer cell and the implanted tumor of nude mice.

AIM: Epidermal growth factor (EGF) plays an important role in the regulation of gastrointestinal tissue growth and development, and it can stimulate epithelial proliferation, cell differentiation and growth. It has been established that the EGF can promote gastric cytoprotection and ulcer healing. But the potential ability of EGF to regulate the gastric cancer growth is unknown. This study is to investigate the influence of EGF on human gastric cancer cell and the implanted tumor growth of nude mice. METHODS: The cell growth rates of human gastric adenocarcinoma cell lines MKN-28, MKN-45, SGC-7901 and normal human gastric epithelial cells 3T3 were assessed when incubated with recombinant human EGF (rhEGF, 0.05, 0.1, 0.5, 1.0, 10, 50, 100 mg.L(-1)) using MTT method. The cells of MKN-28, MKN-45, SGC-7901 (gastric cancer tissue 1.5mm(3)) were implanted in the BALB/cA nude mice for 10 days. The EGF was given intraperitoneally (15, 30, 60 microg.kg(-1)) for 3 weeks. The body weights of the tumor-bearing animals and their tumor mass were measured afterwards to assess the mitogenic effect of rhEGF in the nude mice. RESULTS: Within the concentration range of 0.05-100mg.L(-1), rhEGF could increase the cell growth of normal 3T3 cells (cell growth rate 100% vs 102.8%, P<0.05), but partially restrain the gastric cancer cell growth. The latter effect was related to cell differentiation. In 15-60 microg/kg rhEGF groups, the mean implanted tumor mass of MKN-28 cell were 1.75 g, 1.91 g, 2.08 g/NS group 1.97 g (P>0.05), the mean tumor mass of SGC-7901 cell were 1.53 g, 1.07 g, 1.20 g/NS group 1.07 g (P>0.05), and for MKN-45 cell, the tumor mass were respectively 1.92 g, 1.29 g, 1.77 /NS group 1.82 g (P>0.05). So rhEGF had no obvious effect on implanted MKN-28, SGC-7901 and MKN-45 tumor growth. CONCLUSION: EGF has no stimulating effect on the human gastric cancer cell growth neither in vitro nor in vivo.