Deoxyshikonin: a promising lead drug grass against drug resistance or sensitivity to Helicobacter pylori in an acidic environment.

Helicobacter pylori (H. pylori) is closely associated with the diseases such as gastric sinusitis, peptic ulcers, and gastric adenocarcinoma. Its drug resistance is very severe, and new antibiotics are urgently needed. Nine comfrey compounds were screened by antimicrobial susceptibility testing, among which deoxyshikonin had the best inhibitory effect, with a minimum inhibitory concentration (MIC) of 0.5-1 µg/mL. In addition, deoxyshikonin also has a good antibacterial effect in an acidic environment, it is highly safe, and H. pylori does not readily develop drug resistance. Through in vivo experiments, it was proven that deoxyshikonin (7 mg/kg) had a beneficial therapeutic effect on acute gastritis in mice infected with the multidrug-resistant H. pylori BS001 strain. After treatment with desoxyshikonin, colonization of H. pylori in the gastric mucosa of mice was significantly reduced, gastric mucosal damage was repaired, inflammatory factors were reduced, and the treatment effect was better than that of standard triple therapy. Therefore, deoxyshikonin is a promising lead drug to solve the difficulty of drug resistance in H. pylori, and its antibacterial mechanism may be to destroy the biofilm and cause an oxidation reaction.

Berberine alleviates ovarian tissue damage in mice with hepatolenticular degeneration by suppressing ferroptosis and endoplasmic reticulum stress.

OBJECTIVE: Hepatolenticular degeneration (HLD) is an autosomal recessive disorder that manifests as multiorgan damage due to impaired copper (Cu) metabolism. Female patients with HLD often experience reproductive impairments. This study investigated the protective effect of berberine against ovarian damage in toxic-milk (TX) mice, a murine model for HLD. METHODS: Mice were categorized into control group, HLD TX group (HLD group), penicillamine (Cu chelator)-treated TX group and berberine-treated TX group. Body weight, ovary weight and the number of ovulated eggs were recorded. Follicular morphology and cellular ultrastructure were examined. Total iron, ferrous iron (Fe2+) and trivalent iron (Fe3+) levels, as well as malondialdehyde (MDA), glutathione (GSH) and oxidized glutathione (GSSG), were measured in the ovaries. Western blot analysis was used to analyze the expression of proteins related to ferroptosis and endoplasmic reticulum (ER) stress. RESULTS: Ovarian tissue damage was evident in the HLD group, with a significant increase in ferroptosis and ER stress compared to the control group. This damage was inhibited by treatment with penicillamine, a Cu chelator. Compared with the HLD group, berberine increased the number of ovulations, and improved ovarian morphology and ultrastructure. Further, we found that berberine reduced total iron, Fe2+, MDA and GSSG levels, elevated GSH levels, decreased the expression of the ferroptosis marker protein prostaglandin-endoperoxide synthase 2 (PTGS2), and increased glutathione peroxidase 4 (GPX4) expression. Furthermore, berberine inhibited the expression of ER stress-associated proteins mediated by the protein kinase RNA-like ER kinase (PERK) pathway. CONCLUSION: Ferroptosis and ER stress are involved in Cu-induced ovarian damage in TX mice. Berberine ameliorates ovarian damage in HLD TX mice by inhibiting ferroptosis and ER stress. Please cite this article as: Liu QZ, Han H, Fang XR, Wang LY, Zhao D, Yin MZ, Zhang N, Jiang PY, Ji ZH, Wu LM. Berberine alleviates ovarian tissue damage in mice with hepatolenticular degeneration by suppressing ferroptosis and endoplasmic reticulum stress. J Integr Med. 2024; 22(4): 494-503.

Isobavachalcone: A redox antifungal agent impairs the mitochondria protein of Cryptococcus neoformans.

Isobavachalcone (IBC) is a natural small molecule with various biological activities; however, its inhibitory effects on Cryptococcus neoformans remain unclear. In our study, IBC showed a good antifungal effect. Through in vitro experiments, its minimum inhibitory concentration was 0.5-1 µg/mL. It exhibited the same antifungal effect as Amphotericin B in brain and lung infections in in vivo experiments. IBC also showed a synergistic antifungal effect with emodin with lower toxicity, and C. neoformans did not develop drug resistance to IBC. In the mechanistic study, significantly damaged mitochondria of C. neoformans, a significant reduction in mitochondrial membrane potential and adenosine triphosphate production, and an increase in hydrogen peroxide (H2O2) caused by IBC were observed using transmission electron microscopy. Through drug affinity-responsive target stability combined with phenotype detection, riboflavin synthases of aconitase and succinate dehydrogenase were screened. Molecular docking, quantitative polymerase chain reaction experiments, target inhibitor and agonist intervention, molecular interaction measurements, and minimum inhibitory concentration detection of the constructed expression strains revealed that IBC targeted the activity of these two enzymes, interfered by the tricarboxylic acid cycle, inhibited the production of adenosine triphosphate, blocked electron transport, reduced mitochondrial membrane potential, and induced antioxidation imbalance and reactive oxygen species accumulation, thus producing an antifungal effect. Therefore, IBC is a promising lead drug and redox antifungal agent for C. neoformans.

Radiomics in esophagogastric junction cancer: A scoping review of current status and advances.

PURPOSE: This scoping review aimed to understand the advances in radiomics in esophagogastric junction (EGJ) cancer and assess the current status of radiomics in EGJ cancer. METHODS: We conducted systematic searches of PubMed, Embase, and Web of Science databases from January 18, 2012, to January 15, 2023, to identify radiomics articles related to EGJ cancer. Two researchers independently screened the literature, extracted data, and assessed the quality of the studies using the Radiomics Quality Score (RQS) and the METhodological RadiomICs Score (METRICS) tool, respectively. RESULTS: A total of 120 articles were retrieved from the three databases, and after screening, only six papers met the inclusion criteria. These studies investigated the role of radiomics in differentiating adenocarcinoma from squamous carcinoma, diagnosing T-stage, evaluating HER2 overexpression, predicting response to neoadjuvant therapy, and prognosis in EGJ cancer. The median score percentage of RQS was 34.7% (range from 22.2% to 38.9%). The median score percentage of METRICS was 71.2% (range from 58.2% to 84.9%). CONCLUSION: Although there is a considerable difference between the RQS and METRICS scores of the included literature, we believe that the research value of radiomics in EGJ cancer has been revealed. In the future, while actively exploring more diagnostic, prognostic, and biological correlation studies in EGJ cancer, greater emphasis should be placed on the standardization and clinical application of radiomics.

Construction of an Enzymatically Controlled DNA Nanomachine for One-Step Imaging of Telomerase in Living Cells.

Telomerase is a basic reverse transcriptase that maintains the telomere length in cells, and accurate and specific sensing of telomerase in living cells is critical for medical diagnostics and disease therapeutics. Herein, we demonstrate for the first time the construction of an enzymatically controlled DNA nanomachine with endogenous apurinic/apyrimidinic endonuclease 1 (APE1) as a driving force for one-step imaging of telomerase in living cells. The DNA nanomachine is designed by rational engineering of substrate probes and reporter probes embedded with an enzyme-activatable site (i.e., AP site) and their subsequent assembly on a gold nanoparticle (AuNP). Upon recognition and cleavage of the AP site in the substrate probe by APE1, the loop of the substrate probe unfolds, exposing telomeric primer (TP) with the 3'-OH end. Subsequently, the TP is elongated by telomerase at the 3'-OH end to generate a long telomeric product. The resultant telomeric product acts as a swing arm that can hybridize with a reporter probe to initiate the APE1-powered walking reaction, ultimately generating a significantly enhanced fluorescence signal. Notably, endogenous APE1 is used as the driving force of the DNA nanomachine, avoiding the introduction of exogenous auxiliary cofactors into the cellular microenvironment. Owing to the high kinetics and high amplification efficiency of the APE1-powered DNA nanomachine, this strategy enables one-step sensitive sensing of telomerase in vitro and in vivo. It can successfully discriminate telomerase activity between cancer cells and normal cells, screen telomerase inhibitors, and monitor the variations of telomerase activity in living cells, offering a prospective platform for molecular diagnostics and drug discovery.

RNA methylation-driven assembly of fluorescence-encoded nanostructures for sensitive detection of m6A modification writer METTL3/14 complex in human breast tissues.

N6-methyladenosine (m6A) is an ubiquitous post-transcriptional modification catalyzed by METTL3/14 complex in eukaryotic mRNAs. The abnormal METTL3/14 complex activity affects multiple steps of RNA metabolism and may induce various diseases. Herein, we demonstrate the RNA methylation-driven assembly of fluorescence-encoded nanostructures for sensitive detection of m6A modification writer METTL3/14 complex in human breast tissues. METTL3/14 complex can catalyze the methylation of RNA probe to prevent it from being cleaved by MazF. The intact RNA probe is recognized by the magnetic bead (MB)-capture probe conjugates to induce duplex-specific nuclease (DSN)-assisted cyclic digestion, exposing numerous shorter ssDNAs with 3'-OH end. The shorter ssDNAs on the MB surface can act as the primers to initiate terminal deoxynucleotidyl transferase (TdT)-enhanced tyramide signal amplification (TSA), forming the Cy5 fluorescence-encoded nanostructures. After magnetic separation, the Cy5 fluorescence-encoded nanostructures are digested by DNase I to release abundant Cy5 fluorophores that can be simply quantified by fluorescence measurement. This assay achieves good specificity and high sensitivity with a detection limit of 58.8 aM, and it can screen METTL3/14 complex inhibitors and quantify METTL3/14 complex activity at the single-cell level. Furthermore, this assay can differentiate the METTL3/14 complex level in breast cancer patient tissues and healthy volunteer tissues.

Comparison of two methods for tumour-targeting peptide modification of liposomes.

Liposomes decorated with tumour-targeting cell-penetrating peptides can enhance specific drug delivery at the tumour site. The TR peptide, c(RGDfK)-AGYLLGHINLHHLAHL(Aib)HHIL, is pH-sensitive and actively targets tumour cells that overexpress integrin receptor αvß3, such as B16F10 melanoma cells. Liposomes can be modified with the TR peptide by two different methods: utilization of the cysteine residue on TR to link DSPE-PEG2000-Mal contained in the liposome formula (LIPTR) or decoration of TR with a C18 stearyl chain (C18-TR) for direct insertion into the liposomal phospholipid bilayer through electrostatic and hydrophobic interactions (LIPC18-TR). We found that both TR and C18-TR effectively reversed the surface charge of the liposomes when the systems encountered the low pH of the tumour microenvironment, but LIPC18-TR exhibited a greater increase in the charge, which led to higher cellular uptake efficiency. Correspondingly, the IC50 values of PTX-LIPTR and PTX-LIPC18-TR in B16F10 cells in vitro were 2.1-fold and 2.5-fold lower than that of the unmodified PTX-loaded liposomes (PTX-LIP), respectively, in an acidic microenvironment (pH 6.3). In B16F10 tumour-bearing mice, intravenous administration of PTX-LIPTR and PTX-LIPC18-TR (8 mg/kg PTX every other day for a total of 4 injections) caused tumour reduction ratios of 39.4% and 56.1%, respectively, compared to 20.8% after PTX-LIP administration. Thus, we demonstrated that TR peptide modification could improve the antitumour efficiency of liposomal delivery systems, with C18-TR presenting significantly better results. After investigating different modification methods, our data show that selecting an adequate method is vital even when the same molecule is used for decoration.

Cortisol Stimulates Local Progesterone Withdrawal Through Induction of AKR1C1 in Human Amnion Fibroblasts at Parturition.

Fetal membrane activation is seen as being one of the crucial triggering components of human parturition. Increased prostaglandin E2 (PGE2) production, a common mediator of labor onset in virtually all species, is recognized as one of the landmark events of membrane activation. Fetal membranes are also equipped with a high capacity of cortisol regeneration by 11ß-hydroxysteroid dehydrogenase 1 (11ß-HSD1), and the cortisol regenerated potently induces PGE2 synthesis, an effect normally suppressed by progesterone during gestation. There is no precipitous decline of progesterone synthesis in human parturition. It is intriguing how this suppression is lifted in parturition. Here, we investigated this issue by using human amnion tissue and primary amnion fibroblasts which synthesize the most PGE2 in the fetal membranes. Results showed that the expression of 11ß-HSD1 and aldo-keto reductase family 1 member C1 (AKR1C1), a progesterone-inactivating enzyme, increased in parallel in human amnion tissue with gestational age toward the end of gestation and at parturition. Cortisol induced AKR1C1 expression via the transcription factor CCAAT enhancer binding protein δ (C/EBPδ) in amnion fibroblasts. Inhibition of AKR1C1 not only blocked progesterone catabolism induced by cortisol, but also enhanced the suppression of cortisol-induced cyclooxygenase-2 (COX-2) expression by progesterone in amnion fibroblasts. In conclusion, our results indicate that cortisol regenerated in the fetal membranes triggers local progesterone withdrawal through enhancement of AKR1C1-mediated progesterone catabolism in amnion fibroblasts, so that the suppression of progesterone on the induction of COX-2 expression and PGE2 synthesis by cortisol can be lifted for parturition.

Therapeutic Targets of Bufalin on Renal Carcinoma and Mechanisms: Experimental Validation of Network Pharmacology Analysis.

The possible targets underlying the activity of bufalin on renal cell carcinoma (RCC) were investigated using network pharmacology and experimental approaches. PharmMapper and other databases were explored for predicting the bufalin targets and RCC-related targets. Finally, the enriched pathways and the targets were analyzed by the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) pathway enrichment analyses. Furthermore, in vitro cell experiments were used to verify bufalin activation of AKT and MAPK signaling pathways in human mesangial cells. The therapeutic targets related to bufalin were identified via 35 intersecting targets. GO analysis identified 29 molecular functions, 16 cellular components, and 91 biological processes. KEGG pathway annotation identified 15 signal transduction pathways and 4 tumor-related pathways.

circ_0005379 inhibits the progression of oral squamous cell carcinoma by regulating the miR-17-5p/acyl-CoA oxidase 1 axis.

OBJECTIVES: To investigate the effects of circ_0005379 on the proliferation, apoptosis, migration, and invasion of oral squamous cell carcinoma (OSCC) cells and its mechanism. METHODS: Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression levels of circ_0005379 and miR-17-5p in OSCC tissues and SCC15 cell lines. Western blot was used to detect the expression levels of acyl-CoA oxidase 1 (ACOX1). The circ_0005379 overexpression vector was transfected into SCC15 cells. Methyl thiazolyl tetrazolium blue staining, flow cytometry, Transwell, and Western blot were used to detect the effects of circ_0005379 overexpression on the proliferation, apoptosis, migration, and invasion of SCC15 cells and the expression of E-cadherin, ß-catenin, and Snail proteins. Dual luciferase reporter assay and RNA immunoprecipitation were used to examine the regulation of circ_0005379, miR-17-5p, miR-17-5p, and ACOX1 in SCC15 cells. A nude mouse xenograft model of SCC15 cells stably overexpressing circ_0005379 was established, and the effect of circ_0005379 overexpression on the growth of xenografts in nude mice was observed. RESULTS: Compared with adjacent cancer tissues, the expression levels of circ_0005379 and ACOX1 proteins in OSCC tissues were decreased (P<0.05), and the expression level of miR-17-5p was increased (P<0.05). Compared with HOK-16A cells, the expression levels of circ_0005379 and ACOX1 proteins in SCC15 cell lines were decreased (P<0.05), and the expression level of miR-17-5p was increased (P<0.05). After overexpressing circ_0005379, the activity and number of migrating and invading SCC15 cells and the expression levels of ß-catenin and Snail proteins were decreased (P<0.05); however, the apoptosis rate and expression level of E-cadherin protein were increased (P<0.05). In SCC15 cells, circ_0005379 targeted the negative regulation of miR-17-5p expression, and miR-17-5p targeted the negative regulation of ACOX1 expression. Overexpressing miR-17-5p or silencing ACOX1 could reverse the effects of circ_0005379 overexpression on the proliferation, apoptosis, migration, and invasion of OSCC cell lines. The tumor volume and weight of nude mice overexpressing circ_0005379 were decreased (P<0.05), the expression levels of circ_0005379 and ACOX1 protein in tumor tissues were increased (P<0.05), and the expression level of miR-17-5p was decreased (P<0.05). CONCLUSIONS: circ_0005379 may inhibit the proliferation, migration, and invasion of OSCC cells by downregulating the expression of miR-17-5p and upregulating ACOX1, which promote apoptosis and inhibit tumor growth in vivo. circ_0005379 may be a potential target for OSCC treatment.

[Effect of different orthodontic forces on the expression of T helper cell 17 cell-related cytokines in the pressure side of periodontal tissue in rats].

OBJECTIVES: This study aimed to explore the changes in the expression of the characteristic transcription factor retinoid related orphan receptor γt (RORγt) and the cytokine interleukin-17 (IL-17) of T helper cell 17 (Th17) in the pressure side of the periodontal tissue of rats under different orthodontic forces. Their effects on the expression of osteoprotegerin (OPG) and the quantity of osteoclast (OC) were also explored. The role of Th17 cell in alveolar bone remodeling under different forces was preliminarily investigated. METHODS: A total of 108 rats were chosen and randomly divided into three groups. Mesial forces of 0, 50, and 100 g were loaded on the maxillary first molar in the three groups. The rats were executed at 0, 1, 3, 5, 7, and 14 days. The expression of RORγt mRNA was quantified by real-time quantitative polymerase chain reaction. The expression of IL-17 protein was quantified by enzyme linked immunosorbent assay. The expression levels of RORγt and OPG proteins were quantified, and the quantity of OC was counted via immunohistochemistry. RESULTS: The expression levels of RORγt and IL-17 and the quantity of OC increased first and then decreased in the 50 and 100 g groups, and the peak values of the two groups were on days 5 and 7, respectively. The expression levels in the 50 g group basically recovered to normal level on day 14, while that in the 100 g group remained at a high level. The expression levels in the 50 g group were higher than those in the 0 g group and lower than those in the 100 g group. The expression of OPG in the 50 g group decreased first, then increased, and finally decreased. It basically recovered to normal level on day 14. The expression of OPG in the 100 g group decreased first and then increased. It remained at a high level on day 14. The expression in the 50 g group was significantly higher than that in the 0 g group on day 7, while the expression in the 100 g group was significantly higher than that in the 0 g group on day 14. CONCLUSIONS: RORγt, IL-17, and OPG were expressed regularly over time under different orthodontic forces, indicating that Th17 participated in the process of bone resorption on the pressure side of periodontal tissue by secreting IL-17.

Efficacy of neural stem cell transplantation for the treatment of patients with spinal cord injury: A protocol of systematic review and meta-analysis.

BACKGROUND: The aim of this study is to evaluate the efficacy of neural stem cell transplantation (NSCT) for the treatment of patients with spinal cord injury (SCI). METHODS: All potential randomized controlled trials (RCTs) on NSCT in the treatment of patients with SCI will be searched from the following electronic databases: Cochrane Library, MEDILINE, EMBASE, Web of Science, Scopus, CBM, WANGFANG, and CNKI. We will search all electronic databases from their initiation to the January 31, 2020 in spite of language and publication date. Two contributors will independently select studies from all searched literatures, extract data from included trials, and evaluate study quality for all eligible RCTs using Cochrane risk of bias tool, respectively. Any confusion will be resolved by consulting contributor and a consensus will be reached. We will utilize RevMan 5.3 software to pool the data and to conduct the data analysis. RESULTS: This study will summarize the most recent RCTs to investigate the efficacy and safety of NSCT in the treatment of patients with SCI. CONCLUSION: This study will provide evidence to assess the efficacy and safety of NSCT in the treatment of patients with SCI at evidence-based medicine level. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42020173792.

Calcitonin gene-related peptide attenuates angiotensin II-induced ROS-dependent apoptosis in vascular smooth muscle cells by inhibiting the CaMKII/CREB signalling pathway.

Apoptosis is associated with various cardiovascular diseases. CGRP exerts a variety of effects within the cardiovascular system, and protects against the onset and development of angiotensin (Ang) II-induced vascular dysfunction and remodelling. However, it is not known whether CGRP has a direct effect on Ang II-induced apoptosis in vascular smooth muscle cells (VSMCs), and the mechanism underlying the anti-apoptotic role remains unclear. In this study, CGRP significantly suppressed reactive oxygen species (ROS) and apoptosis in Ang II-induced VSMCs. In VSMCs pre-treated with a CGRP receptor antagonist (CGRP8-37), the CGRP-mediated inhibition of Ang II-induced ROS and apoptosis was completely abolished. Moreover, pre-treatment with N-acetyl-L cysteine (NAC), an ROS scavenger, blocked the effects of CGRP on Ang II-induced apoptosis. In addition, the activation of CaMKII and the downstream transcription factor CREB stimulated by Ang II was abrogated by CGRP. Importantly, in both CGRP and NAC-treated VSMCs, CGRP failed to further attenuate CaMKII and CREB activation. The results demonstrate that CGRP attenuated Ang II-induced ROS-dependent apoptosis in VSMCs by inhibiting the CaMKII/CREB signalling pathway.

Novel Copper Complexes That Inhibit the Proteasome and Trigger Apoptosis in Triple-Negative Breast Cancer Cells.

Five innovative ternary copper(II) complexes [Cu(OH-PIP)(Phe)Cl](1), [Cu(OH-PIP)(Gly)(H2O)]NO3·2H2O (2), [Cu(OH-PIP)(Ala)(Cl)]·H2O (3), [Cu(OH-PIP)(Met)]PF6·2H2O (4), and [Cu(OH-PIP)(Gln)(H2O)](Cl)·3H2O (5) have been synthesized and characterized by infrared spectroscopy, elemental analysis, and single crystal X-ray diffraction analysis. X-ray crystallography indicates that all Cu atoms are five-coordinated in a square-pyramidal configuration. The complexes have been screened for cytotoxicity against human breast cancer cell lines MCF-7, MDA-MB-231, and CAL-51. The best anticancer activity is obtained with triple-negative breast cancer CAL-51 and MDA-MB-231 cell lines, with IC50 values in the range of 0.082-0.69 µM. Importantly, the copper compounds were more effective than carboplatin at triggering cell death. Mechanistically, the complexes inhibit proteasomal chymotrypsin-like activity, and docking studies reveal their 20S proteasome binding sites. As a consequence, they cause the accumulation of ubiquitinated proteins, inhibit cell proliferation, and induce apoptosis. In addition, these copper complexes decrease the stemness of triple-negative breast cancer cells and have synergistic effects with CBP on TNBC cells, indicating their great potential as a novel therapy for triple-negative breast cancer.

Improved method for inducing chronic atrophic gastritis in mice.

BACKGROUND: Chronic atrophic gastritis (CAG) is a common disease of the digestive system with pathological characteristics of a decreasing number, or disappearance, of inherent glands of the gastric mucosa. CAG has been defined as a precancerous condition of gastric cancer. Intestinal metaplasia or intraepithelial neoplasia accompanying atrophied glands of the stomach is regarded as one of the most important precancerous lesions of gastric cancer. As a common malignant tumour, gastric cancer remains without a satisfactory therapy and its pathogenesis remains unclear, seriously threatening human life. Therefore, some scholars have proposed to prevent the incidence of gastric cancer by avoiding precancerous lesions. If CAG can be reversed, the incidence of gastric cancer can be substantially reduced. To reverse and prevent CAG and study its pathogenesis and therapy, it is necessary to develop an ideal, safe, stable, animal model. AIM: To study a rapid, stable, and safe method of establishing a mouse model of human CAG. METHODS: Six-week-old Kunming mice were divided into a phosphate buffered solution control group, a Helicobacter pylori (H. pylori) group, an N-methyl-N'-nitroguanidine (MNNG) group, an ammonia water group, and a group combining H. pylori, MNNG, and ammonia water (hereinafter referred to as the combined group). The mice were administrated with drinking water containing ammonia or infected with H. pylori through gavage. At the 30th, 60th, 90th, and 120th day after the last H. pylori infection, mice were selected randomly to collect their gastric mucosa for hematoxylin eosin staining, terminal nick-end labelling staining detection, and immunohistochemical staining for Bax and Bcl-2. In addition, H. pylori was isolated, cultured, and identified, and its extent of colonisation calculated. Blood was collected to detect inflammatory factors interleukin (IL)-1ß, IL-8, and tumor necrosis factor (TNF)-α and immune function markers CD4 and CD8 to confirm successful establishment of the CAG model. RESULTS: The combined group showed slight CAG at the 90th day and moderate CAG at the 120th day, while other groups did not show CAG at that time. CONCLUSION: The combination of H. pylori, MNNG, and ammonia is an effective method of developing a mouse model of human CAG.

Core cis-element variation confers subgenome-biased expression of a transcription factor that functions in cotton fiber elongation.

Cotton cultivars have evolved to produce extensive, long, seed-born fibers important for the textile industry, but we know little about the molecular mechanism underlying spinnable fiber formation. Here, we report how PACLOBUTRAZOL RESISTANCE 1 (PRE1) in cotton, which encodes a basic helix-loop-helix (bHLH) transcription factor, is a target gene of spinnable fiber evolution. Differential expression of homoeologous genes in polyploids is thought to be important to plant adaptation and novel phenotypes. PRE1 expression is specific to cotton fiber cells, upregulated during their rapid elongation stage and A-homoeologous biased in allotetraploid cultivars. Transgenic studies demonstrated that PRE1 is a positive regulator of fiber elongation. We determined that the natural variation of the canonical TATA-box, a regulatory element commonly found in many eukaryotic core promoters, is necessary for subgenome-biased PRE1 expression, representing a mechanism underlying the selection of homoeologous genes. Thus, variations in the promoter of the cell elongation regulator gene PRE1 have contributed to spinnable fiber formation in cotton. Overexpression of GhPRE1 in transgenic cotton yields longer fibers with improved quality parameters, indicating that this bHLH gene is useful for improving cotton fiber quality.

Capsaicin enhances the antitumor activity of sorafenib in hepatocellular carcinoma cells and mouse xenograft tumors through increased ERK signaling.

Sorafenib, a small inhibitor of tyrosine protein kinases, is currently the standard chemotherapy drug for the treatment of advanced hepatocellular carcinoma (HCC). Although sorafenib improves the survival of HCC patients, its efficacy is not optimal and requires further improvement. Capsaicin, the major active component of chili peppers from the genus Capsicum, is not only the agonist of TRPV1 channel, but also displays antitumor activity and enhances the sensitivity of cancer cells to cytotoxic drugs. In this study, we investigated the antitumor effects of combined sorafenib and capsaicin on HCC cells in vitro and xenograft tumors. Treatment with capsaicin alone dose-dependently inhibited the proliferation of the HCC cell lines PLC/PRF/7, HuH7 and HepG2 with IC50 values of 137, 108 and 140.7 µmol/L, respectively. No obvious expression of TRPV1 channel was detected in the 3 HCC cell lines and TRPV1 channel blockers did not alleviate the cytotoxicity of capsaicin. By contrast, combining capsaicin and sorafenib significantly enhanced the suppression on cell proliferation, achieving a high-level synergistic effect (inhibition rates over 50%) and promoting HCC cell apoptosis. In nude mice with PLC/PRF/5 xenografts, combined administration of capsaicin and sorafenib significantly enhanced the suppression on tumor growth without apparent gross toxicity compared to either agent alone. Mechanistically, capsaicin (10-200 µmol/L) dose-dependently increased the levels of phosphorylated ERK (p-ERK) in PLC/PRF/5 cells, thus leading to enhanced sorafenib sensitivity and a synergistic suppression on the tumor cells. Taken together, our results suggest that capsaicin-increased phosphorylation of ERK contributes to the enhanced antitumor activity of sorafenib, and capsaicin may be useful in improving the efficacy of sorafenib for the treatment of HCC.

Di-isopropyl ether assisted crystallization of organic-inorganic perovskites for efficient and reproducible perovskite solar cells.

Organic-inorganic perovskite solar cells have emerged as a promising photovoltaic technology because of their advantages such as low cost, high efficiency, and solution processability. The performance of perovskite solar cells is highly dependent on the crystallinity and morphology of the perovskite films. Herein, we report a simple, one-step anti-solvent deposition process using di-isopropyl ether as a dripping solvent to obtain extremely uniform and highly crystalline CH3NH3PbI3 perovskite films. Compared to toluene, chlorobenzene, chloroform, or diethyl ether, di-isopropyl ether has proven to be a more suitable solvent for an anti-solvent deposition process. The perovskite solar cells fabricated by the anti-solvent deposition process using di-isopropyl ether treatment exhibit an average power conversion efficiency (PCE) of 17.67 ± 0.54% and the highest PCE of 19.07%. Moreover, the higher boiling point of di-isopropyl ether makes the anti-solvent deposition process more tolerant to elevated ambient temperature, which can be carried out at ambient temperatures up to 40 °C. Our results demonstrate that di-isopropyl ether is an excellent dripping solvent in the anti-solvent deposition process for efficient and reproducible perovskite solar cells.

Molecular cloning, characterization, and promoter analysis of the isochorismate synthase (AaICS1) gene from Artemisia annua.

Isochorismate synthase (ICS) is a crucial enzyme in the salicylic acid (SA) synthesis pathway. The full-length complementary DNA (cDNA) sequence of the ICS gene was isolated from Artemisia annua L. The gene, named AaICS1, contained a 1710-bp open reading frame, which encoded a protein with 570 amino acids. Bioinformatics and comparative study revealed that the polypeptide protein of AaICS1 had high homology with ICSs from other plant species. Southern blot analysis suggested that AaICS1 might be a single-copy gene. Analysis of the 1470-bp promoter of AaICS1 identified distinct cis-acting regulatory elements, including TC-rich repeats, MYB binding site (MBS), and TCA-elements. An analysis of AaICS1 transcript levels in multifarious tissues of A. annua using quantitative real-time polymerase chain reaction (qRT-PCR) showed that old leaves had the highest transcription levels. AaICS1 was up-regulated under wounding, drought, salinity, and SA treatments. This was corroborated by the presence of the predicted cis-acting elements in the promoter region of AaICS1. Overexpressing transgenic plants and RNA interference transgenic lines of AaICS1 were generated and their expression was compared. High-performance liquid chromatography (HPLC) results from leaf tissue of transgenic A. annua showed an increase in artemisinin content in the overexpressing plants. These results confirm that AaICS1 is involved in the isochorismate pathway.

Low toxic and high soluble camptothecin derivative 2-47 effectively induces apoptosis of tumor cells in vitro.

The cytotoxic activity of camptothecin derivatives is so high that these compounds need to be further modified before their successful application as anti-cancer agents clinically. In this study, we reported the synthesis and biological evaluation of a novel camptothecin derivative called compound 2-47. The changes in structure did not reduce its activity to inhibit DNA topoisomerase I. Compound 2-47 induced apoptosis of many tumor cells including leukemia cells K562, Jurkat, HL-60, breast cancer cell BT-549, colon cancer cell HT-29 and liver cancer cell HepG2 with a half maximal inhibitory concentration (IC50) of 2- to 3-fold lower than HCPT as a control. In particular, 2-47 inhibited the proliferation of Jurkat cells with an IC50 of as low as 40 nM. By making use of Jurkat cell as a model, following treatment of Jurkat cells, compound 2-47 activated caspase-3 and PARP, resulting in a decreased Bcl-2/Bax ratio. These data showed that compound 2-47 induces Jurkat cell death through the mitochondrial apoptotic pathway. In addition, compound 2-47 showed a decreased cytotoxic activity against normal cells and an improved solubility in low-polar solvent. For example, compound 2-47 solutes in CHCl3 130-fold higher than HCPT. Taken together, our data demonstrated that camptothecin derivative 2-47 notably inhibits the tumor cell proliferation through mitochondrial-mediated apoptosis in vitro.