148 research outputs found
New strategy for the search of natural biologically active substances.
The modern pharmaceutics actively screens an immense diversity of substances occurring in plants and other natural resources in the search for new effective medicinal agents. The Global Institute for Bioexploration (GIBEX) established by joint efforts of Rutgers University and the University of Illinois (United States) represents the organizational core of international scientific community whose activity is directed towards the search and development of new medicinal preparations from natural raw materials. The basis of GIBEX activity is the transfer of modern screening technologies to countries and geographical regions characterized by remarkable biodiversity. The GIBEX goals are to encourage the search for new natural biologically active substances, to maintain biodiversity, and to monitor the natural resources conservation
MyD88-dependent and independent pathways of Toll-Like Receptors are engaged in biological activity of Triptolide in ligand-stimulated macrophages
<p>Abstract</p> <p>Background</p> <p>Triptolide is a diterpene triepoxide from the Chinese medicinal plant <it>Tripterygium wilfordii </it>Hook F., with known anti-inflammatory, immunosuppressive and anti-cancer properties.</p> <p>Results</p> <p>Here we report the expression profile of immune signaling genes modulated by triptolide in LPS induced mouse macrophages. In an array study triptolide treatment modulated expression of 22.5% of one hundred and ninety five immune signaling genes that included Toll-like receptors (TLRs). TLRs elicit immune responses through their coupling with intracellular adaptor molecules, MyD88 and TRIF. Although it is known that triptolide inhibits NFκB activation and other signaling pathways downstream of TLRs, involvement of TLR cascade in triptolide activity was not reported. In this study, we show that triptolide suppresses expression of proinflammatory downstream effectors induced specifically by different TLR agonists. Also, the suppressive effect of triptolide on TLR-induced NFκB activation was observed when either MyD88 or TRIF was knocked out, confirming that both MyD88 and TRIF mediated NFκB activation may be inhibited by triptolide. Within the TLR cascade triptolide downregulates TLR4 and TRIF proteins.</p> <p>Conclusions</p> <p>This study reveals involvement of TLR signaling in triptolide activity and further increases understanding of how triptolide activity may downregulate NFκB activation during inflammatory conditions.</p
Designing a Clinical Study With Dietary Supplements: It\u27s All in the Details
A successful randomized clinical trial of the effect of dietary supplements on a chosen endpoint begins with developing supporting data in preclinical studies while paying attention to easily overlooked details when planning the related clinical trial. In this perspective, we draw on our experience studying the effect of an ethanolic extract from Artemisia dracunculus L. (termed PMI-5011) on glucose homeostasis as a potential therapeutic option in providing resilience to metabolic syndrome (MetS). Decisions on experimental design related to issues ranging from choice of mouse model to dosing levels and route of administration in the preclinical studies will be discussed in terms of translation to the eventual human studies. The more complex considerations in planning the clinical studies present different challenges as these studies progress from testing the safety of the dietary supplement to assessing the effect of the dietary supplement on a predetermined clinical outcome. From the vantage point of hindsight, we will outline potential pitfalls when translating preclinical studies to clinical studies and point out details to address when designing clinical studies of dietary supplements
High-Fat Diet-Induced Neuropathy of Prediabetes and Obesity: Effect of PMI-5011, an Ethanolic Extract of Artemisia dracunculus L.
Artemisia species are a rich source of herbal remedies with antioxidant and anti-inflammatory properties. We evaluated PMI-5011, an ethanolic extract of Artemisia dracunculus L., on neuropathy in high-sfat diet-fed mice, a model of prediabetes and obesity developing oxidative stress and proinflammatory changes in peripheral nervous system. C57Bl6/J mice fed high-fat diet for 16 weeks developed obesity, moderate nonfasting hyperglycemia, nerve conduction deficit, thermal and mechanical hypoalgesia, and tactile allodynia. They displayed 12/15-lipoxygenase overexpression, 12(S)-hydroxyeicosatetraenoic acid accumulation, and nitrosative stress in peripheral nerve and spinal cord. PMI-5011 (500 mgkg−1d−1, 7 weeks) normalized glycemia, alleviated nerve conduction slowing and sensory neuropathy, and reduced 12/15-lipoxygenase upregulation and nitrated protein expression in peripheral nervous system. PMI-5011, a safe and nontoxic botanical extract, may find use in treatment of neuropathic changes at the earliest stage of disease
Tricin levels and expression of flavonoid biosynthetic genes in developing grains of purple and brown pericarp rice
The methylated flavone tricin has been associated with numerous health benefits, including reductions in intestinal and colon cancers in animal models. Tricin is found in a wide range of plant species and in many different tissues. However, whole cereal grains, such as rice, barley, oats, and wheat, are the only food sources of tricin, which is located in the bran portion of the grain. Variation in tricin levels was found in bran from rice genotypes with light brown, brown, red, and purple pericarp color, with the purple pericarp genotypes having the highest levels of tricin. Here, we analyzed tricin and tricin derivative levels in developing pericarp and embryo samples of a purple pericarp genotype, IAC600, that had high tricin and tricin derivative levels in the bran, and a light brown pericarp genotype, Cocodrie, that had no detectable tricin or tricin derivatives in the bran. Tricin and tricin derivatives were detected in both the pericarp and embryo of IAC600 but only in the embryo of Cocodrie. The purple pericarp rice had higher total levels of free tricin plus tricin derivatives than the light brown pericarp rice. When expressed on a per grain basis, most of the tricin component of IAC600 was in the pericarp. In contrast, Cocodrie had no detectable tricin in the pericarp samples but did have detectable chrysoeriol, a precursor of tricin, in the pericarp samples. We also used RNA-Seq analysis of developing pericarp and embryo samples of the two cultivars to compare the expression of genes involved in the flavonoid biosynthetic pathway. The results presented here suggest that understanding the basis of tricin accumulation in rice pericarp may lead to an approach to increasing tricin levels in whole grain rice. From analysis of gene expression levels in the pericarp samples it appears that regulation of the flavone specific genes is independent of regulation of the anthocyanin biosynthetic genes. It therefore may be feasible to develop brown pericarp rice cultivars that accumulate tricin in the pericarp
Tools for the identification of bioactives impacting the metabolic syndrome: Screening of a botanical extract library using subcutaneous and visceral human adipose-derived stem cell-based assays
Plant extracts continue to represent an untapped source of renewable therapeutic compounds for the treatment and prevention of illnesses including chronic metabolic disorders. With the increase in worldwide obesity and its related morbidities, the need for identifying safe and effective treatments is also rising. As such, use of primary human adipose-derived stem cells represents a physiologically relevant cell system to screen for bioactive agents in the prevention and treatment of obesity and its related complications. By using these cells in a primary screen, the risk and cost of identifying artifacts due to interspecies variation and immortalized cell lines is eliminated. We demonstrate that these cells can be formatted into 384-well high throughput screens to rapidly identify botanical extracts that affect lipogenesis and lipolysis. Additionally, counterscreening with human primary stem cells from distinct adipose depots can be routinely performed to identify tissue specific responses. In our study, over 500 botanical extracts were screened and 16 (2.7%) were found to affect lipogenesis and 4 (0.7%) affected lipolysis. © 2012 Elsevier Inc
Metabolomic differences between invasive alien plants from native and invaded habitats
Globalization facilitated the spread of invasive alien species (IAS), undermining the stability of the world’s ecosystems. We investigated the metabolomic profiles of three IAS species: Chromolaena odorata (Asteraceae) Datura stramonium (Solanaceae), and Xanthium strumarium (Asteraceae), comparing metabolites of individual plants in their native habitats (USA), to their invasive counterparts growing in and around Kruger National Park (South Africa, ZA). Metabolomic samples were collected using RApid Metabolome Extraction and Storage (RAMES) technology, which immobilizes phytochemicals on glass fiber disks, reducing compound degradation, allowing long-term, storage and simplifying biochemical analysis. Metabolomic differences were analyzed using ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) of samples eluted from RAMES disks. Partial Least Squares-Discriminant Analysis (PLS-DA) of metabolomes of individual plants allowed statistical separation of species, native and invasive populations of each species, and some populations on the same continent. Invasive populations of all species were more phytochemically diverse than their native counterparts, and their metabolomic profiles were statistically distinguishable from their native relatives. These data may elucidate the mechanisms of successful invasion and rapid adaptive evolution of IAS. Moreover, RAMES technology combined with PLS-DA statistical analysis may allow taxonomic identification of species and, possibly, populations within each species
Rapid, field-deployable method for collecting and preserving plant metabolome for biochemical and functional characterization
Study of plant metabolome is a growing field of science that catalogs vast biochemical and functional diversity of phytochemicals. However, collecting and storing samples of plant metabolome, sharing these samples across the scientific community and making them compatible with bioactivity assays presents significant challenges to the advancement of metabolome research. We have developed a RApid Metabolome Extraction and Storage (RAMES) technology that allows efficient, highly compact, field-deployable collection and storage of libraries of plant metabolome. RAMES technology combines rapid extraction with immobilization of extracts on glass microfiber filter discs. Two grams of plant tissue extracted in ethanol, using a specially adapted Dremel® rotary tool, produces 25±35 replicas of 10 mm glass fiber discs impregnated with phytochemicals. These discs can be either eluted with solvents (such as 70% ethanol) to study the metabolomic profiles or used directly in a variety of functional assays. We have developed simple, non-sterile, anti-fungal, antibacterial, and anti-oxidant assays formatted for 24-multiwell plates directly compatible with RAMES discs placed inside the wells. Using these methods we confirmed activity in 30 out of 32 randomly selected anti-microbial medicinal plants and spices. Seven species scored the highest activity (total kill) in the anti-bacterial (bacteria from human saliva) and two antifungal screens (Fusarium spp. and Saccharomyces cerevisiae), providing functional validation of RAMES technology. RAMES libraries showed limited degradation of compounds after 12 months of storage at -20ÊC, while others remained stable. Fifty-eight percent of structures characterized in the extracts loaded onto RAMES discs could be eluted from the discs without significant losses. Miniaturized RAMES technology, as described and validated in this manuscript offers a labor, cost, and time-effective alternative to conventional collection of phytochemicals. RAMES technology enables creation of comprehensive metabolomic libraries from various ecosystems and geographical regions in a format compatible with further biochemical and functional studies
Distinct Fractions of an Artemisia scoparia Extract Contain Compounds With Novel Adipogenic Bioactivity
Adipocytes are important players in metabolic health and disease, and disruption of adipocyte development or function contributes to metabolic dysregulation. Hence, adipocytes are significant targets for therapeutic intervention in obesity and metabolic syndrome. Plants have long been sources for bioactive compounds and drugs. In previous studies, we screened botanical extracts for effects on adipogenesis in vitro and discovered that an ethanolic extract of Artemisia scoparia (SCO) could promote adipocyte differentiation. To follow up on these studies, we have used various separation methods to identify the compound(s) responsible for SCO's adipogenic properties. Fractions and subfractions of SCO were tested for effects on lipid accumulation and adipogenic gene expression in differentiating 3T3-L1 adipocytes. Fractions were also analyzed by Ultra Performance Liquid Chromatography- Mass Spectrometry (UPLC-MS), and resulting peaks were putatively identified through high resolution, high mass accuracy mass spectrometry, literature data, and available natural products databases. The inactive fractions contained mostly quercetin derivatives and chlorogenates, including chlorogenic acid and 3,5-dicaffeoylquinic acid, which had no effects on adipogenesis when tested individually, thus ruling them out as pro-adipogenic bioactives in SCO. Based on these studies we have putatively identified the principal constituents in SCO fractions and subfractions that promoted adipocyte development and fat cell gene expression as prenylated coumaric acids, coumarin monoterpene ethers, 6-demethoxycapillarisin and two polymethoxyflavones
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