Recent advances in gut microbiota-associated natural products: structures, bioactivities, and mechanisms.

Covering: 2014 to June 2022The gut microbiota has attracted increasing attention from researchers due to its critical role in regulating human physiology and pathophysiology. Natural products (NPs) produced or transformed by gut microbes are key signalling mediators for a variety of physiological functions. On the other hand, NPs from ethnomedicines have also been found to generate health benefits through modulation of the gut microbiota. In this highlight, we review the most recent studies related to gut microbiota-derived NPs and bioactive NPs that regulate physiological and pathological processes via gut microbiota-associated mechanisms. We also outline the strategies for the discovery of gut microbiota-derived NPs and the methodologies of how to elucidate the crosstalk between bioactive NPs and the gut microbiota.

Construction and heterologous expression of the di-AFN A1 biosynthetic gene cluster in Streptomyces model strains.

Natural cyclohexapeptide AFN A1 fromStreptomyces alboflavus 313 has moderate antibacterial and antitumor activities. An artificial designed AFN A1 homodimer, di-AFN A1, is an antibiotic exhibiting 10 to 150 fold higher biological activities, compared with the monomer. Unfortunately, the yield of di-AFN A1 is very low (0.09 ± 0.03 mg·L-1) in the engineered strain Streptomyces alboflavus 313_hmtS (S. albo/313_hmtS), which is not friendly to be genetically engineered for titer improvement of di-AFN A1 production. In this study, we constructed a biosynthetic gene cluster for di-AFN A1 and increased its production through heterologous expression. During the collection of di-AFN A1 biosynthetic genes, the afn genes were located at three sites of S. alboflavus 313 genome. The di-AFN A1 biosynthetic gene cluster (BGC) was first assembled on one plasmid and introduced into the model strain Streptomyces lividans TK24, which produced di-AFN A1 at a titer of 0.43 ± 0.01 mg·L-1. To further increase the yield of di-AFN A1, the di-AFN A1 BGC was multiplied and split to mimic the natural afn biosynthetic genes, and the production of di-AFN A1 increased to 0.62 ± 0.11 mg·L-1 in S. lividans TK24 by the later strategy. Finally, different Streptomyces hosts were tested and the titer of di-AFN A1 increased to 0.81 ± 0.17 mg·L-1, about 8.0-fold higher than that in S. albo/313_hmtS. Successful heterologous expression of di-AFN A1 with a remarkable increased titer will greatly facilitate the following synthetic biological study and drug development of this dimeric cyclohexapeptide.

Low-level laser treatment promotes skin wound healing by activating hair follicle stem cells in female mice.

The aim of the study was to explore the effect and mechanism of a low-level laser on hair follicle stem cells in full-thickness skin wound healing in mice. Full-thickness skin defects were generated by a 5-mm punch biopsy tool on the backs of depilated C57/BL6N mice, which were randomly divided thereafter into a low-dose laser treatment group (LLLT-Low), a high-dose laser treatment group (LLLT-High), and a control group (control). From the day of modeling to the day before the skin samples were taken, the wound area and wound edge of the mice in the LLLT-Low and LLLT-High groups were irradiated with a laser comb every 24 h, and the energy density was 1 J/cm2 and 10 J/cm2, respectively. The control group was irradiated with an ordinary fluorescent lamp. At 0, 3, 5, 10, and 14 days after modeling, pictures of each wound were taken, and the percent wound closure was analyzed. At 3, 5, 10, and 14 days after modeling, the samples were observed by hematoxylin and eosin (HE) and immunofluorescence (IF) staining. Whole transcriptome sequencing (RNA-Seq) was performed on the samples on day 10. Gene Ontology (GO) analysis was performed, and the results were validated by Western blot analysis and enzyme-linked immunosorbent assay (ELISA). The analysis of the percent of wound closure showed that healing was accelerated (significantly from 5 to 10 days) in the LLLT-Low group, but there was no clear change in the LLLT-High group. HE staining showed that the LLLT-Low group had an increasing number of hair follicles and a tendency to migrate to the center of the wound. There was no significant increase in the number of hair follicles and no obvious migration in the LLLT-High group. Immunofluorescence staining showed that the total number of CK15 + hair follicle stem cells in the LLLT-Low group was higher than that in the control group and LLLT-High group at all time points. The number and farthest migration distance of CK15 + hair follicle stem cells increased significantly with time, and after 5 days, they were significantly higher than those in the control group and LLLT-High group. RNA-Seq and Western blot analysis showed that the expression of related genes in hair follicle stem cells, including CK15, in the LLLT-Low group was upregulated. GO analysis and ELISA showed that the expression of many cytokines, represented by IL34, in the LLLT-Low group was upregulated. Low-level laser treatment can promote the proliferation, differentiation, and migration of CK15 + hair follicle stem cells by upregulating the cytokine IL34, thereby promoting skin wound healing in mice.

Fe(II) enhances simultaneous phosphorus removal and denitrification in heterotrophic denitrification by chemical precipitation and stimulating denitrifiers activity.

Using Fe(II) salt as the precipitant in heterotrophic denitrification achieves improved TP removal, and enhancement in denitrification was often observed. This study aimed to obtain a better understanding of Fe(II)-enhanced denitrification with sufficient carbon source supply. Laboratory-scale experiments were conducted in SBRs with or without Fe(II) addition. Remarkably improved TP removal was experienced. TP removal efficiency in Fe(II) adding reactor was 85.8 ± 3.4%; whereas, that in the reactor without Fe(II) addition was 31.1 ± 2.8%. Besides improved TP removal, better TN removal efficiency (94.1 ± 1.1%) were recorded when Fe(II) was added, and that in the reactor without Fe(II) addition was 89 ± 0.8%. The specific denitrification rate were observed increase by 12.6% when Fe(II) was added. Further microbial analyses revealed increases in the abundances of typical denitrifiers (i.e. Niastella, Opitutus, Dechloromonas, Ignavibacterium, Anaeromyxobacter, Pedosphaera, and Myxococcus). Their associated denitrifying genes, narG, nirS, norB, and nosZ, were observed had 14.2%, 19.4%, 21.6%, and 9.9% elevation, respectively. Such enhancement in denitrification shall not be due to nitrate-dependent ferrous oxidation, which prevails in organic-deficient environments. In an environment with a continuous supply of Fe(II) and plenty of carbon sources, a cycle of denitrifying enzyme activity enhancement in the presence of Fe(II) facilitating nitrogen substrate utilization, stimulating denitrifier metabolism and growth, elevating denitrifying genes abundance, and increasing denitrifying enzymes expression were thought to be responsible for the Fe(II)-enhanced heterotrophic denitrification. Fe(II) salt is often a less expensive precipitant and has recently become attractive for TP removal in wastewater. The findings of this study solidify previous observation of enhancement of both TP and TN removal by adding Fe(II) in denitrification, and would be helpful for developing cost-effective pollutant removal processes.

Effects of Malaria Interventions During Pregnancy on Low Birth Weight in Malawi.

INTRODUCTION: In malaria-endemic countries, malaria during pregnancy is associated with adverse birth outcomes, including low birth weight (i.e., <2.5 kg). However, the effects of the widely promoted and recommended approaches of intermittent preventive treatment for malaria in pregnancy and insecticide-treated nets for pregnant women on low birth weight have been insufficiently examined. This analysis investigates the independent and combined effects of intermittent preventive treatment for malaria in pregnancy and insecticide-treated nets on low birth weight among Malawian children. METHODS: Using pooled data sets from 2004, 2010, and 2015-2016 Malawi Demographic and Health Surveys, a total of 18,285 births were analyzed between August and December 2019. Binomial generalized linear regression models with a log-link function explored the associations under consideration. RESULTS: The overall low birth weight prevalence was 10.3%. Prevalence was lower in children whose mothers used adequate intermittent preventive treatment for malaria in pregnancy (adjusted prevalence ratio=0.88, 95% CI=0.79, 0.99) or used insecticide-treated nets (adjusted prevalence ratio=0.89, 95% CI=0.79, 0.99) than their respective counterparts. Low birth weight was 20.0% lower among children whose mothers adequately used both intermittent preventive treatment for malaria in pregnancy and insecticide-treated nets than those without these approaches (adjusted prevalence ratio=0.80, 95% CI=0.68, 0.93). Iron supplement consumption and survey year were significant effect modifiers on the relationship between intermittent preventive treatment for malaria in pregnancy and low birth weight. CONCLUSIONS: There were evident benefits of independent and combined use of intermittent preventive treatment for malaria in pregnancy and insecticide-treated nets on low birth weight, thereby supporting the use of these interventions during pregnancy. The reduced protective effects of intermittent preventive treatment for malaria in pregnancy over time highlight the need for innovative preventive methods against malaria in pregnancy.

Design, synthesis and evaluation of phenylthiazole and phenylthiophene pyrimidindiamine derivatives targeting the bacterial membrane.

As the continuous rise in the incidence of antibiotic resistance, it is urgent to develop novel chemical scaffolds with antibacterial activities to control the spread of resistance to conventional antibiotics. In this study, a series of phenylthiazole and phenylthiophene pyrimidindiamine derivatives were designed and synthesized by modifying the hit compound (N2-isobutyl-N4-((4-methyl-2-phenylthiazol-5-yl)methyl) pyrimidine-2,4-diamine) and their antibacterial activities were evaluated both in vitro and in vivo. Among the tested compounds, compound 14g (N4-((5-(3-bromophenyl)thiophen-2-yl)methyl)-N2-isobutylpyrimidine-2,4-diamine) displayed the best antibacterial activities, which was not only capable of inhibiting E. coli and S. aureus growth at concentrations as low as 2 and 3 µg/mL in vitro, but also efficacious in a mice model of bacteremia in vivo. Unlike conventional antibiotics, compound 14g was elucidated to mainly destroy the bacterial cell membrane, with the dissipation of membrane potential and leakage of contents, ultimately leading to cell death. The destruction of cell structure is challenging to induce bacterial resistance, which suggested that compound 14g may be a kind of promising alternatives to antibiotics against bacteria.

Parthenolide, an NF-κB inhibitor, alleviates peritoneal fibrosis by suppressing the TGF-ß/Smad pathway.

Transforming growth factor (TGF)-ß/Smad signalling plays a central role in the pathogenesis of peritoneal fibrosis related to peritoneal dialysis (PD). Parthenolide (PTL), a naturally occurring phytochemical, is isolated from the shoots of feverfew (Tanacetum parthenium) and displays analgesia, anti-inflammation and anticancer activities. In this study, we examined the therapeutic potential of PTL on PD-related peritoneal fibrosis induced by daily intraperitoneal injection of 4.25% dextrose-containing PD fluid (PDF) in vivo and TGF-ß1-induced epithelial-mesenchymal transition (EMT) in vitro. PTL was administered daily before PDF injection or after 14 days of PDF injection. Both PTL treatments showed a protective effect on peritoneal fibrosis and prevented peritoneal dysfunction. Similarly, PTL suppressed the expression of fibrotic markers (fibronectin and collagen I) and restored the expression of the epithelial marker (E-cadherin) in TGF-ß1-treated HMrSV5 cells. Furthermore, PTL inhibited TGF-ß1-induced Smad2 and Smad3 phosphorylation and nuclear translocation but did not influence Smad1/5/9 phosphorylation or activate other downstream signalling pathways of TGF-ß1, including AKT, extracellular signal-regulated kinase (ERK) or p38. In conclusion, PTL treatment may represent an effective and novel therapy for PD-associated peritoneal fibrosis by suppressing the TGF-ß/Smad pathway.

Micheliolide ameliorates diabetic kidney disease by inhibiting Mtdh-mediated renal inflammation in type 2 diabetic db/db mice.

Diabetic kidney disease (DKD) is the principal cause of end-stage renal disease worldwide and few treatments are available. Because immunomodulators are pivotal to DKD pathophysiology, anti-inflammatory agents may be useful for treating DKD. This study was conducted to investigate the effect of micheliolide (MCL), a novel guaianolide sesquiterpene lactone with well-known anti-inflammatory effects, on DKD. Treatment with dimethylaminomicheliolide (DMAMCL), the pro-drug of MCL currently under clinical trial in oncology, protected the kidneys against proteinuria, renal failure, histopathological injury, and inflammation in db/db mice. This effect was associated with metadherin (Mtdh) downregulation. We observed aberrant upregulation of Mtdh in the kidneys of db/db mice and high-glucose (HG)-induced mouse tubular epithelial cells (mTECs). Downregulation of Mtdh obviously inhibited nuclear factor-κB signaling activation and suppressed its downstream inflammatory cytokines, such as monocyte chemotactic peptide-1, interleukin-1ß, tumor necrosis factor-α, and interleukin-6 in HG-induced mTECs, which was similar to the effect of MCL. Mtdh overexpression largely reversed the anti-inflammatory role of MCL. Moreover, MCL downregulated Mtdh by both inhibiting the transcription level and promoting ubiquitin-mediated degradation. These findings suggest that DMAMCL is a promising anti-inflammatory agent useful for preventing renal injury in DKD by inhibiting Mtdh-mediated renal inflammation.

Characterization of a Bi-directional Promoter OtrRp Involved in Oxytetracycline Biosynthesis.

Previous studies identified a MarR (multiple antibiotic resistance regulator) family transcription factor OtrR in the oxytetracycline biosynthetic gene cluster, which regulated the expression of an efflux pump OtrB. The genes otrB and otrR were divergent arranged and the inter-ORF (open reading frame) region between the two genes contained the promoter otrBp. In this study, we demonstrated that the reverse complementary sequence of otrBp contained the promoter of otrR, and its activity was also repressed by OtrR by sharing the same operator otrO within otrBp, and allosteric regulated by oxytetracycline. Our findings offered a solid base for the synthetic biological application of the bi-direction promoter in controlling two elements at the same time using only one signal molecule.

Characteristics of particle size distribution and related contaminants of highway-deposited sediment, Maanshan City, China.

Road-deposited sediment (RDS) has been identified as both the source and sink of various pollutants. In this study, the highway-deposited sediment (HDS) in Spring, Summer, Autumn and Winter was characterized. On average, the mass proportions of particles with the size of 830-4750 µm, 500-830 µm, 250-500 µm, 150-250 µm, 63-150 µm and < 63 µm were 23.6 ± 8.6%, 16.9 ± 3.4%, 28.4 ± 3.5%, 10.0 ± 4.3%, 15.7 ± 5.8% and 5.3 ± 2.0%, respectively, wherein the HDS of 63-830 µm accounted for 71% of the total mass load. It was observed that the particle size distribution of HDS could be described using the gamma distribution function based on gravimetric and cumulative basis (R2 (determination coefficient) = 0.9960-0.9995). The bulk pollutant contents of HDS showed seasonal variation with the mean of COD (chemical oxygen demand), nitrogen, phosphorus, Zn (zinc), Pb (lead) and Cd (cadmium) as 57 g/kg, 839 mg/kg, 97 mg/kg, 627 mg/kg, 110 mg/kg and 1.00 mg/kg and the highest COD of 83 g/kg in Autumn, nitrogen 1164 mg/kg Autumn, phosphorus 133 mg/kg Winter, Zn 801 mg/kg Summer, Pb 133 mg/kg Spring and the highest Cd of 1.36 mg/kg in Summer, respectively. The contents of Zn, Pb and Cd in HDS were significantly above their local soil background values. Moreover, the size fractional pollutant contents overall increased as particles' size increased. Averagely, 40-52% pollutant loads were associated with the particles < 250 µm, which can be moved easily by runoff. This study suggests that the behaviors of HDS different from city RDS should be considered as nonpoint source pollution control is performed.

Dimethylaminomicheliolide ameliorates peritoneal fibrosis through the activation of autophagy.

Peritoneal fibrosis (PF) is a major cause of ultrafiltration failure in patients receiving long-term peritoneal dialysis (PD), and effective prevention and treatment strategies are urgently needed. The dimethylamino Michael adduct of a natural product-derived micheliolide (MCL), dimethylaminomicheliolide (DMAMCL), is a new lead compound with the advantages of high stability, low toxicity, and sustainable release of MCL. This study aimed to investigate the protective effect of DMAMCL against PD-related PF and the mechanisms involved. In this study, we found that DMAMCL significantly decreased PD-induced extracellular matrix (ECM) deposition in a mouse model of PD, and that delayed DMAMCL administration halted the progression of PF in an established PD model. In addition, rapamycin administration induced autophagy and significantly ameliorated PF. The protective effect of DMAMCL against PF was weakened when co-administered with DMAMCL and 3-methyladenine. Inducing autophagy by rapamycin decreased transforming growth factor-ß1-induced ECM accumulation in vitro. MCL promoted autophagy and inhibited ECM deposition. The anti-fibrotic effect of MCL was eliminated when knocking down ATG7 by siRNA. Taken together, DMAMCL might prevent against PF through activating autophagy. The anti-fibrotic effect of DMAMCL may be a new candidate for the treatment in patients with PD-related PF. KEY MESSAGES: Dimethylaminomicheliolide, the pro-drug of micheliolide, protects against peritoneal fibrosis in a mouse peritoneal dialysis model. Micheliolide inhibits TGF-ß1-induced extracellular matrix accumulation in vitro. Autophagy plays a protective role against peritoneal fibrosis. The antifibrogenic effect of dimethylaminomicheliolide may be due to the activation of autophagy.

Clinicopathological features, diagnosis, and treatment of IgA nephropathy with minimal change disease related to exposure to mercury-containing cosmetics: a case report
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AIM: Membranous nephropathy and minimal change disease (MCD) have been involved in mercury-induced nephrotic syndrome. IgA nephropathy is not known to be a common pathological type. In the present article, we report a case of IgA nephropathy with MCD following exposure to mercury-containing skin lightening cream. MATERIAL AND METHODS: The patient was a 39-year-old woman who presented with nephrotic syndrome. She had a 6-month history of using as many as 8 kinds of skin-lightening creams, and urinary mercury excretion was high. Renal biopsy revealed IgA nephropathy with MCD. The use of cosmetics was stopped and chelation therapy was given. After 4 courses (1 month) of chelation therapy, there was a complete remission of proteinuria and hematuria, and urine tests remained normal during the 5-year follow-up period. RESULTS AND CONCLUSIONS: The unique clinical and pathological features of IgA nephropathy with MCD had raised the controversial question of whether MCD and IgA deposition are separate entities or a common pathophysiology. Repeated renal biopsy and similar cases were helpful and should be carried out as far as possible.
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12-Deoxyphorbol 13-palmitate inhibit VEGF-induced angiogenesis via suppression of VEGFR-2-signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: 12-Deoxyphorbol 13-palmitate (G) is one toxic compound isolated from Euphorbia fischeriana, an Asian spice used for cancer treatment as a folk remedy. However, whether 12-deoxyphorbol 13-palmitate affects angiogenesis remains unclear. AIM OF THE STUDY: To explore the in vitro and in vivo antiangiogenic effects of 12-deoxyphorbol 13-palmitate and its underlying mechanisms. MATERIALS AND METHODS: We explored antigenic functions in human umbilical vein endothelial cells (HUVEC) by 12-deoxyphorbol 13-palmitate, including proliferation, migration and metastasis through matrigel plug assay, chorioallantoic membrane assay, in vitro migration assay, tube formation assay, motility assay. Antibody chip was applied to screen differentially expressed proteins modulated by 12-deoxyphorbol 13-palmitate, and was further confirmed by RT-PCR and western blot analysis. Tumor xenograft mice were applied to investigate whether 12-deoxyphorbol 13-palmitate could inhibit microvessel density in vivo. RESULTS: 12-Deoxyphorbol 13-palmitate inhibited vascular endothelial growth factor (VEGF)-induced angiogenic processes in vitro, such as proliferation, in vitro migration, and tube formation of HUVEC. In chorioallantoic membrane assay, 12-deoxyphorbol 13-palmitate significantly inhibited neovessel formation. Antibody chip technology demonstrated decreased expression of TIMP-1, TIMP-2, VEGF, basic fibroblast growth factor (bFGF), matrix metalloproteinases (MMP)-2, VEGFR-2 and VEGFR-3 proteins in HUVEC after 24h. In addition, 12-deoyphorbol 13-palmitate inhibited the in vivo growth of MCF-7 cells in grafted mouse model. Immunohistochemistry staining showed decreased microvessel density (CD31) and attenuated VEGFR-2 signaling pathways by 12-deoxyphorbol 13-palmitate. CONCLUSION: 12-Deoxyphorbol 13-palmitate may be utilized to target active angiogenesis through VEGF/VEGFR2 signal pathway for cancer.

Cucurbitacin E inhibits breast tumor metastasis by suppressing cell migration and invasion.

Tumor metastasis is the main cause of cancer-related deaths of patients. Breast cancer is highly malignant with considerable metastatic potential, which urges the necessity for developing novel potential drug candidate to prevent tumor metastasis. Here, we report our finding with Cucurbitacin E (CuE, α-elaterin), a tetracyclic triterpenes compound isolated from Cucurbitaceae. The potency of CuE on breast cancer metastasis inhibition was assessed in vivo and in vitro. In our animal experiments, intraperitoneal administrations of CuE significantly inhibited breast tumor metastasis to the lung without affecting apoptosis or proliferation of inoculated 4T1 and MDA-MB-231 breast cancer cells. Treatment of metastatic breast tumor cells with CuE markedly blocked tumor cell migration and invasion in vitro. Subsequent studies showed that CuE impaired Arp2/3-dependent actin polymerization and suppressed Src/FAK/Rac1/MMP involved pathway. Overall, our data demonstrate that CuE blocks breast cancer metastasis by suppressing tumor cell migration and invasion. We provide first evidence of a novel role for CuE as a potential candidate for treating breast cancer metastasis.

Incidence, mortality, and causes of death of patients with pemphigus in Taiwan: a nationwide population-based study.

Pemphigus is a potentially life-threatening autoimmune blistering disease. However, little is known about the all-cause and cause-specific mortality among patients with pemphigus compared with the general population. The incidence of pemphigus in Taiwan has not been described previously. The objective of this study was to estimate the incidence of pemphigus in Taiwan and to investigate the overall mortality, causes of death, and cause-specific mortality in a nationwide population-based cohort of pemphigus patients. The study cohort included 853 patients newly diagnosed with pemphigus between 2002 and 2009 in the National Health Insurance Research Database. Survival status, date of death, and cause of death were ascertained by linking the study cohort with the National Register of Deaths Database of Taiwan. All-cause and cause-specific standardized mortality ratios (SMRs) were estimated. The incidence of pemphigus in Taiwan was 4.7 (95% confidence interval (CI), 3.2-6.2) per million per year. Overall, 88 deaths were observed during a mean follow-up period of 3.8 years, which was more than two times the number expected (SMR, 2.36; 95% confidence interval, 1.92-2.91). In the analysis of causes of death, the SMRs for death due to pneumonia (3.64; 95% CI, 1.30-10.21), septicemia (11.57; 95% CI, 2.95-45.34), cardiovascular disease (2.69; 95% CI, 1.18-6.12), and peptic ulcer disease (8.44; 95% CI, 1.22-58.21) were significantly higher than expected. We concluded that the incidence of pemphigus is not low in Taiwan, and the overall mortality among pemphigus patients is two times greater than that of the general population. In particular, patients with pemphigus have higher risk of mortality from systemic and respiratory tract infections, cardiovascular disease, and peptic ulcer disease.

A quantitative method for the measurement of membrane affinity by polydiacetylene-based colorimetric assay.

The measurement of membrane affinity is an important early screening step during drug discovery. However, classical methods for membrane affinity measurement are tedious and difficult to implement in high-throughput screening. This article describes a quantitative method for the measurement of membrane affinity by colorimetric assay based on polydiacetylene (PDA) sensors. Prepared lipid/PDA chromatic vesicles were used to model cell membranes. By measuring the colorimetric response of the chromatic vesicles when drug-membrane interactions occurred, membrane affinity constant K(b) could be calculated using a simple quantitative model. Under optimized preparation conditions, the calculated log(K(b)) values exhibited an in-batch relative standard deviation (RSD) of less than 4% and a between-batch RSD of less than 8% for all three reference compounds. The logarithm of K(b) of the six ß-blockers exhibited excellent linear correlation with the logarithm of the liposome/water partition coefficient (K(m)) with R(2)=0.9793. For neutral compounds, the log(K(b)) of n-fatty alcohols correlated with the logarithm of the n-octanol/water partition coefficient (K(oct)) with a linear correlation coefficient R(2)=0.9833. This work provides a simple, convenient, and reproducible method for the rapid measurement of membrane affinity and presents important implications for high-throughput screening.

Caffeic acid 3,4-dihydroxy-phenethyl ester induces cancer cell senescence by suppressing twist expression.

Compared with traditional cytotoxic cancer therapy, therapy-induced cancer cell senescence attracts much interest because it is similarly effective, has fewer side effects, and is more efficiently cleared by immune cells. In this study, we demonstrate that unlike caffeic acid phenethyl ester, caffeic acid 3,4-dihydroxy-phenethyl ester (CADPE), which is isolated from the medicinal plants Sarcandra glabra and Teucrium pilosum, inhibits human cancer cell growth and colony formation by inducing cancer cell senescence, not apoptosis. CADPE induces cell senescence and morphology changes by increasing cellular size and cytoplasmic granularity, enhancing senescence-associated ß-galactosidase activity and differentiated embryo-chondrocyte expressed gene 1 expression, and blocking cell-cycle arrest in the G(1) phase. To help understand the underlying mechanisms, we show that CADPE significantly suppressed the expression of Twist1 and led to the up-regulation of rat sarcoma, p53, p21(WAF1/CIP1), and p16(INK4a) proteins in a dose-dependent manner, resulting in the hypophosphorylation of retinoblastoma protein. Furthermore, overexpression of Twist1 prevented CADPE-induced cell senescence in tumor cells. Therefore, our studies provide evidence for a novel role of CADPE in cancer cell senescence by targeting the Twist1-dependent senescence signaling pathway.

Increased risk of avoidable hospitalization among patients with schizophrenia.

OBJECTIVE: Some studies suggest that hospitalizations for certain conditions, called ambulatory care sensitive conditions (ACSCs), are potentially avoidable. However, almost no study has addressed the risk of ACSC hospitalizations specifically for patients with severe mental illness. Our study examines the risk of ACSC hospitalizations among patients with schizophrenia in Taiwan, using a 5-year, nationwide, population-based database. METHODS: Our study included 2503 patients with schizophrenia and 20 024 matched patients without schizophrenia. Poisson regression analysis was then performed in which the number of ACSC hospitalizations from 2002 to 2006 (including ruptured appendix, asthma, cellulitis, congestive heart failure, diabetes, gangrene, hypokalemia, immunizable conditions, malignant hypertension, pneumonia, pyelonephritis, and perforated or bleeding ulcer) was regressed against the independent variable of whether or not a patient had a schizophrenia diagnosis in 2001. RESULTS: Results show that 9.83% of patients with schizophrenia and 4.71% of patients in the comparison group experienced ACSC hospitalizations from 2002 to 2006. After adjusting for each patient's sex, age, level of urbanization, geographic location of residence within a community, and monthly income, patients with schizophrenia had a 3.26-fold higher (95% CI 3.00 to 3.54, P < 0.001) risk of experiencing ACSC hospitalizations than the comparison participants. After excluding the conditions of diabetes, hypertension, and asthma, patients with schizophrenia independently had a 2.46-fold higher risk of ACSC hospitalizations (95% CI 2.12 to 2.86, P < 0.001), compared with participants in the comparison group. CONCLUSIONS: We conclude that schizophrenia patients are at a higher risk for hospitalizations owing to ACSCs, despite a national health insurance system providing universal coverage to citizens.

Hispidulin, a small flavonoid molecule, suppresses the angiogenesis and growth of human pancreatic cancer by targeting vascular endothelial growth factor receptor 2-mediated PI3K/Akt/mTOR signaling pathway.

Hispidulin, an active component from Artemisia vestita, a traditional Tibetan medicinal plant, has been shown to possess anti-inflammatory and anti-oxidative activities. However, the functional role of hispidulin on tumor growth and angiogenesis has not been elucidated. We found that hispidulin significantly inhibited human pancreatic tumor growth in xenograft mice when s.c. treated at a dosage of 20 mg/kg daily, and this effect was accompanied with a potent inhibition on angiogenesis. When examining the cytotoxicity of hispidulin on HUVECs and pancreatic cancer cells in vitro, we found that HUVECs were more susceptible to the treatment, suggesting angiogenesis might be the primary target of hispidulin. Our results further showed that hispidulin inhibited vascular endothelial growth factor (VEGF)-induced cell migration, invasion, and capillary-like structure formation of HUVECs in a dose-dependent manner. In ex vivo and in vivo angiogenesis assays, we showed that hispidulin suppressed VEGF-induced microvessel sprouting of rat aortic rings and corneal neovascularization in C57/BL6 mice. To understand the underlying molecular basis, we next examined the effects of hispidulin on different molecular components in treated HUVECs, and found that hispidulin suppressed the VEGF-triggered activation of VEGF receptor 2, PI3K, Akt, mTOR, and ribosomal protein S6 kinase, but had little effect on focal adhesion kinase or extracellular signal-regulated kinase at an effective concentration. Taken together, our results indicate that hispidulin targets the VEGF receptor 2-mediated PI3K/Akt/mTOR signaling pathway in endothelial cells, leading to the suppression of pancreatic tumor growth and angiogenesis.