Mycoepoxydiene inhibits antigen-stimulated activation of mast cells and suppresses IgE-mediated anaphylaxis in mice

Draft Genome Sequence of Diaporthe sp. Strain HANT25, an Endophytic Fungus Producing Mycoepoxydiene

Diaporthe sp. strain HANT25 is an endophytic fungus that produces mycoepoxydiene, a rare bioactive natural compound. Here, we report the genome sequence of Diaporthe sp. HANT25, comprising 55.3 Mb in 80 scaffolds. The genome sequence should enhance understanding of the biology and bioactive compound production potential of the genus Diaporthe.

Current Research Landscape of Marine-Derived Anti-Atherosclerotic Substances

Atherosclerosis is a chronic disease characterized by lipid accumulation and chronic inflammation of the arterial wall, which is the pathological basis for coronary heart disease, cerebrovascular disease and thromboembolic disease. Currently, there is a lack of low-cost therapeutic agents that effectively slow the progression of atherosclerosis. Therefore, the development of new drugs is urgently needed. The research and development of marine-derived drugs have gained increasing interest from researchers across the world. Many marine organisms provide a rich material basis for the development of atherosclerotic drugs. This review focuses on the latest technological advances in the structures and mechanisms of action of marine-derived anti-atherosclerotic substances and the challenges of the application of these substances including marine polysaccharides, proteins and peptides, polyunsaturated fatty acids and small molecule compounds. Here, we describe the theoretical basis of marine biological resources in the treatment of atherosclerosis.

Mangrove-Associated Fungi: A Novel Source of Potential Anticancer Compounds

Cancer is the second leading cause of death worldwide, and the number of cases is increasing alarmingly every year. Current research focuses on the development of novel chemotherapeutic drugs derived from natural as well as synthetic sources. The abundance and diversity in natural resources offer tremendous potential for the discovery of novel molecules with unique mechanisms for cancer therapy. Mangrove-derived fungi are rich source of novel metabolites, comprising novel structure classes with diverse biological activities. Across the globe, coastal areas are primarily dominated by mangrove forests, which offer an intensely complex environment and species that mostly remain unexplored. In recent years, many structurally diverse compounds with unique skeletons have been identified from mangrove fungi and evaluated for their antiproliferative properties. These compounds may serve as lead molecules for the development of new anticancer drugs. Mangrove endophytes can be modulated using epigenetic means or culture optimization methods to improve the yield or to produce various similar analogs. The present review provides an insight into the bioactive metabolites from mangrove endophytes reported during the period from 2012 to 2018 (up to April, 2018) along with their cytotoxic properties, focusing on their chemical structures and mode of action, as indicated in the literature.

Cytotoxic Polyketides with an Oxygen-Bridged Cyclooctadiene Core Skeleton from the Mangrove Endophytic Fungus Phomosis sp. A818

Plant endophytic microorganisms represent a largely untapped resource for new bioactive natural products. Eight polyketide natural products were isolated from a mangrove endophytic fungus Phomosis sp. A818. The structural elucidation of these compounds revealed that they share a distinct feature in their chemical structures, an oxygen-bridged cyclooctadiene core skeleton. The study on their structure-activity relationship showed that the α,β-unsaturated δ-lactone moiety, as exemplified in compounds 1 and 2, was critical to the cytotoxic activity of these compounds. In addition, compound 4 might be a potential agonist of AMPK (5'-adenosine monophosphate-activated protein kinase).

Mycoepoxydiene suppresses HeLa cell growth by inhibiting glycolysis and the pentose phosphate pathway

Upregulation of glycolysis and the pentose phosphate pathway (PPP) is a major characteristic of the metabolic reprogramming of cancer and provides cancer cells with energy and vital metabolites to support their rapid proliferation. Targeting glycolysis and the PPP has emerged as a promising antitumor therapeutic strategy. Marine natural products are attractive sources for anticancer therapeutics, as evidenced by the antitumor drug Yondelis. Mycoepoxydiene (MED) is a natural product isolated from a marine fungus that has shown promising inhibitory efficacy against HeLa cells in vitro. We used a proteomic approach with two-dimensional gel electrophoresis (2-DE) coupled with mass spectrometry to explore the cellular targets of MED and to unravel the molecular mechanisms underlying the antitumor activity of MED in HeLa cells. Our proteomic data showed that triosephosphate isomerase (TPI) and 6-phosphogluconolactonase (PGLS), which participate in glycolysis and the PPP, respectively, were significantly downregulated by MED treatment. Functional studies revealed that the expression levels of several other enzymes involved in glycolysis and the PPP, including hexokinase 2 (HK2), phosphofructokinase 1 (PFKM), aldolase A (ALDOA), enolase 1 (ENO1), lactate dehydrogenase A (LDHA), and glucose-6-phosphate dehydrogenase (G6PD), were also reduced in a dose-dependent manner. Moreover, the LDHA and G6PD enzymatic activities in HeLa cells were inhibited by MED, and overexpression of these downregulated enzymes rescued HeLa cells from the growth inhibition induced by MED. Our data suggest that MED suppresses HeLa cell growth by inhibiting glycolysis and the PPP, which provides a mechanistic basis for the development of new therapeutics against cervical cancer.

Decreased Level of IgE is Associated with Breast Cancer and Allergic Diseases

Background

The aim of this study was to explore the prevalence of type I allergic diseases in patients with breast cancer by carrying out a questionnaire survey and IgE detection in a healthy population and in patients with breast cancer.

Material/Method

There were 309 patients enrolled and they were further divided into the type I allergic disease group, the newly diagnosed breast cancer with type I allergic disease group, the re-visit breast cancer with type I allergic disease group, and the re-visit breast cancer without type I allergic disease group, as well as a healthy control group. Serum total IgE level was detected by immunoassay.

Results

The IgE value in the healthy population with type I allergic diseases (89.3±51.4 IU/ml) was significantly higher than in those without type I allergic diseases (45.6±65.1 IU/ml). There was no significant difference between IgE values in the re-visit breast cancer patients with type I allergic disease (25.1±65.1 IU/ml) and those without type I allergic disease (23.0±45.9 IU/ml). The area under the ROC curve was 0.618±0.04, sensitivity was 78%, specificity was 47.1%, Youden index was 0.251, and IgE threshold was 32.6 IU/ml.

Conclusions

The patients with newly diagnosed breast cancer were susceptible to type I allergic disease at about the same levels as in the healthy population. There was no correlation between breast cancer and type I allergic disease.

Inhibitory effects of Mycoepoxydiene on macrophage foam cell formation and atherosclerosis in ApoE-deficient mice

Background

Mycoepoxydiene (MED) is a polyketide that can be isolated from a marine fungus and is associated with various activities, including antitumor and anti-inflammatory functions. However, its effects on atherosclerosis remain unknown. Macrophage-derived foam cells play crucial roles in the initiation and progression of atherosclerotic plaques. In this study, we investigated the effects of MED on oxidized low-density lipoprotein (ox-LDL)-induced macrophage foam cell formation and activation, and on high fat diet (HFD)-induced atherosclerosis in ApoE-deficient (ApoE^−/−) mice.

Results

Our findings show that MED could significantly inhibit ox-LDL-induced macrophage foam cell formation and suppress the expression of lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), which is a receptor for ox-LDL. Additionally, MED could significantly inhibit the secretion of proinflammatory cytokines, such as tumor necrosis factor (TNF-α), interleukin (IL)-6, and IL-1β. Mechanistically, MED inhibited NF-κB activation by blocking IκB-α degradation and reducing NF-κB DNA binding activity. Moreover, MED dramatically reduced the occurrence of HFD-induced atherosclerotic lesions in ApoE^−/− mice.

Conclusions

Our study shows that MED can inhibit macrophage foam cell formation and activation by inhibiting NF-κB activation, thereby protecting ApoE^−/− mice from HFD-induced atherosclerosis. Our findings suggest that MED might be a potential lead compound for the development of antiatherosclerotic therapeutics.

Electronic supplementary material

The online version of this article (doi:10.1186/s13578-015-0017-y) contains supplementary material, which is available to authorized users.

Recent investigations of bioactive natural products from endophytic, marine-derived, insect pathogenic fungi and Thai medicinal plants

Living organisms in Thailand are very diverse due to the unique geographical location of Thailand. The diversity of Thai bioresources has proven to be a rich source of biologically active compounds. The present review covers bioactive substances from Thai endophytic, marine-derived, insect pathogenic fungi and medicinal plants. Many new compounds isolated from Thai bioresources have diverse skeletons belonging to various classes of natural products. These compounds exhibited an array of biological activities, and some are of pharmaceutical interest. Bioactive compounds from Thai bioresources have not only attracted organic chemists to develop strategies for total synthesis, but also attracted (chemical) biologists to investigate the mechanisms of action. The chemistry and biology of some selected compounds are also discussed in this review.