Research Luc Pieters

Abstract

Ellagitannin-rich herbal remedies are used traditionally because of their anti-inflammatory activity. This is connected not to the ellagitannins themselves but to their metabolites produced by the gut microbiota. Urolithin A (UroA) is recognized as the most significant of all ellagitannins' metabolites. However, not everyone is able to have it produced in their gut. The UroA production is exclusive to the hosts of urolithin metabotype A (UM-A) and B (UM-B) and is most probably dependent on the gut microbiota composition and activity. Preliminary trials showed that UM-A hosts have a lower risk of cardiovascular disease. Moreover, the transition from UM-A to other metabotypes is also connected to aging, which might suggest losing certain beneficial abilities. The identity of microorganisms that differentiate UroA producers were not yet revealed. If recognized, new probiotics might be designed. Providing non-UM-A hosts with the possibility to produce UroA efficiently would grant them an advantage due to reports of a wide range of proven and indicated UroAs biological activities. The project aims to isolate, characterize and preserve bacterial strains able to produce UroA from the fecal samples of UM-A and UM-B donors. This will be possible due to innovative substrate conversion screening strategies and novel metabolomic and sequencing techniques utilization. Results will provide missing insights about urolithin metabotypes for further explanatory studies focused on the elucidation of UM-dependant features. Moreover, bioinformatic tools will be developed to obtain multi-omic descriptions of the studied processes, combining metabolomic and targeted metagenomic data. The project will deliver protocols and data analysis methods that will enable us to run advanced projects in the field of natural products biotransformation research. The established pipelines will be suitable also for dysbiosis, xenobiotic-microbiome interaction and pre- and probiotic design studies.

Researcher(s)

• Promoter: Pieters Luc
• Co-promoter: Hermans Nina
• Co-promoter: Laukens Kris
• Co-promoter: Tuenter Emmy
• Fellow: Popowski Dominik

Research team(s)

• Natural Products & Food Research and Analysis - Pharmaceutical Technology (NatuRAPT)

Project type(s)

• Research Project

Abstract

Broad objective: To document traditional medicines used in management of Sickle Cell Disease (SCD) and malaria in Tanzania, and evaluate their efficacy, safety and active phytochemicals. Specific Objectives: i. To document traditional medicines used in the management of SCD and malaria in Tanzania. ii. To determine the in vitro anti-sickling and antiplasmodial activities of the crude extracts of Tanzanian medicinal plants used for the management of SCD and malaria. iii. To determine safety profile of the selected medicinal plants used in the management of SCD and malaria in Tanzania. iv. To identify bioactive compounds with the anti-sickling activity of the compounds from most promising traditional medicines used in the management of SCD in Tanzania. v. To identify bioactive compounds with the antiplasmodial activity of the compounds from most promising traditional medicines used in the management of malaria in Tanzania.

Researcher(s)

• Promoter: Pieters Luc
• Promoter: Tuenter Emmy

Research team(s)

• Natural Products & Food Research and Analysis - Pharmaceutical Technology (NatuRAPT)

Project type(s)

• Research Project

Abstract

Due to global warming and increased sun exposure, skin cancer has a high incidence and increasing prevalence within the Cuban population. An extract obtained from the local marine plant Thalassia testudinum, rich in polyphenols, has shown effective photoprotection properties and antitumor activity against skin cancer. Until now, the extract production implicates the collection of the species from its natural habitat. However, such approach may endanger biodiversity and eco-sustainability as T. testudinum (known as turtle paste) nurtures other species and plays a central role in the coral reef-seagrass-mangrove ecosystem, which in turn protects the dune from extreme weather events, the coastal communities and the archipelago itself. To preserve the environment, ecological alternatives will be developed for efficient production of secondary metabolites facilitated by abiotic elicitors via bioreactor, tissue culture and plant biotechnology. The obtained biomolecules will next be conjugated to nanostructures to promote synergistic biological effects and to increase therapeutic efficacy. Altogether, environmental friendly and eco-sustainable production strategies will be developed for novel safe and effective pharmaceutical formulations from T. testudinum applicable in the prophylaxis of skin cancer, a serious health problem in Cuba. The overall goal is to strengthen training of gender balanced male and female researchers and build up institutional infrastructure capacities in blue (marine) and green (plant) biotechnology applications to improve health of the Cuban population and to stimulate sustainable eco-friendly circular bio-economy in Cuba. The uptake and outreach of the solutions here achieved may improve international visibility of local institutions, reinforcing global citizenship while education, access to scientific advancement and its benefits, health and human welfare (basic human rights) are improved.

Researcher(s)

• Promoter: Vanden Berghe Wim
• Co-promoter: Pieters Luc
• Co-promoter: Tuenter Emmy

Research team(s)

• Cell death signaling (CDS)

Project type(s)

• Research Project

Abstract

Collaborative studies refer to interlaboratory studies carried out to ensure the highest level of objectivity in the establishment of reference standards or reference methods of the European Pharmacopoeia (EP).

Researcher(s)

• Promoter: Pieters Luc

Research team(s)

• Natural Products & Food Research and Analysis - Pharmaceutical Technology (NatuRAPT)

Project type(s)

• Research Project

Abstract

Many acute and chronic diseases are either driven or modulated by inflammation. This project focuses on 3 classes of natural products that hold great promise towards anti-inflammatory targets, i.e. oxindole alkaloids and phenanthridone alkaloids, both acting on the NF-kB pathway; and iridoids targeting COX activity. Because of their potential activity against NF-kB, a series of oxindole alkaloids will be isolated from Uncaria tomentosa and U. rhynchophylla, in order to evaluate their NF-kB inhibitory properties. In addition, also the activity on the same target of phenanthridone alkaloids, a poorly explored class of compounds from the Amaryllidaceae family, will be evaluated. Many iridoid-containing medicinal plants are known for their anti-inflammatory properties, Harpagophytum procumbens (Devil's claw) being a well-known example. Iridoids often occur as glycosides; it has been shown that they have to be hydrolyzed first by beta-glucosidase activity of the microflora in the gastro-intestinal tract, but the structures of the ultimately active compounds are not known. In the present project iridoid glycosides will be isolated from H. procumbens, and several in vitro approaches will be followed to prepare and to characterize the metabolites, which will then be evaluated for inhibition of COX-1/2 activity. Finally, a human pilot study will be carried out to detect and to quantify in blood plasma the metabolites that were active in vitro.

Researcher(s)

• Promoter: Pieters Luc
• Promoter: Tuenter Emmy

Research team(s)

• Natural Products & Food Research and Analysis - Pharmaceutical Technology (NatuRAPT)

Project type(s)

• Research Project

Abstract

Researcher(s)

• Promoter: Pieters Luc

Research team(s)

• Natural Products & Food Research and Analysis - Pharmaceutical Technology (NatuRAPT)

Project type(s)

• Research Project

Abstract

The Experimental Pharmacy unit at the Institute of Pharmacy and Food was initially created for the production and commercialization of Natural Products approved by the Ministry of Health Public. Recently, the functions of Experimental Pharmacy unit changed to be a Center for Research-Development, Production and Commercialization of Natural Products. This strategy was made to close the cycle for the introduction of new herbal medicines, natural cosmetics and functional foods from the Cuban universities. However, the capacities of the Experimental Pharmacy unit to reach this aim are limited. In this context, the present initiative aims to increase the capacities of the Experimental Pharmacy unit for the research-development of natural products. Additionally, it is necessary to increase the productive capacity and the variety of products for commercialization. In order to reach these aims, four strategies were developed for the present project: 1) to increase the capacity of Cuban researchers in new methodologies for research on natural products, 2) to improve our methodologies and technologies, 3) to strengthen the international cooperation alliances for the interchange of knowledge and the search for other opportunities of financial support; and 4) to establish commercial agreements with national distributors of raw materials and herbal products. The financial support of the European Union acquired by the ADELANTE Project will be used to organize fourteen activities to carry out these strategies.

Researcher(s)

• Promoter: Pieters Luc

Research team(s)

• Natural Products & Food Research and Analysis - Pharmaceutical Technology (NatuRAPT)

Project type(s)

• Research Project

Abstract

The Royal Decree KB 29.08.1997 updated in 2017 (KB 24.01.2017 ), imposes the criteria and analytical requirements to which herbal food supplements (containing plants) must comply. These requirements are defined as "does not contain detectable amounts of …" or specify a "maximalamount of ..." a particular compound or class of compounds. However, in many cases appropriate analytical procedures are lacking or not adequate. The general objective of this project is to develop and validate analytical methods to detect (and to establish detection limits) or to quantify concerned products.

Researcher(s)

• Promoter: Pieters Luc
• Co-promoter: Hermans Nina

Research team(s)

Project type(s)

• Research Project

Abstract

During previous investigations in the host laboratory it has been found that several classes of natural products, i.e. polymethoxy-flavones, biflavonoids, xanthones and quinazoline alkaloids, exhibited AGEs inhibiting properties. AGEs (or Advanced Glycation Endproducts) are implicated in many age-related chronic diseases and in protein ageing, and are associated with diabetic complications, atherosclerosis, neurodegenerative diseases, cancer and the normal ageing processes. AGEs have been found to induce autophagy, a favourable subcellular process contributing to cellular homeostasis and adaptation to stress by removing damaged or unwanted intracellular material. Similar to AGEs, autophagy has been associated with different pathological conditions including heart disease, cancer and neurodegeneration. Autophagy is stimulated in atherosclerosis and in oxidative stress conditions. Therefore, AGEs inhibition and modulation of autophagy were selected as targets to be evaluated and to establish structure-activity relationships for the product classes mentioned above. Both AGEs inhibition and modulation of autophagy are relatively new targets in natural product research. AGEs inhibitors and inducers of autophagy, or a combination of both, may be potentially useful products against degenerative diseases in a broad sense, such as the ones mentioned above.

Researcher(s)

• Promoter: Pieters Luc
• Fellow: Velichkova Stefaniya

Research team(s)

Project type(s)

• Research Project

Abstract

REVICO aims to develop innovative fermentation and downstream processing methods to allow a sustainable and optimal use of various cocoa bean components and their specific applications, in particular regarding flavour and health-promoting components.

Researcher(s)

• Promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

Aim of this innovation project is the introduction of the black soldier fly as a new sustainable source of lipids, from which "green surfactants" can be produced using green and less poluting chemical synthetic pathways. The project involves (1) purification of insect lipids (solvent extraction followed by traditional and enzymatic degumming methods); (2) production of green surfactants (case studies in cooperation with industrial partners); (3) characterisation of the surfactants produced; (4) perception by consumerrs about the use of insect-derived lipids in non-food products.

Researcher(s)

• Promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

This project represents a formal research agreement between UAntwerpen and on the other hand the client. UAntwerpen provides the client research results mentioned in the title of the project under the conditions as stipulated in this contract.

Researcher(s)

• Promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

This project represents a formal research agreement between UA and on the other hand VLIR. UA provides VLIR research results mentioned in the title of the project under the conditions as stipulated in this contract. The aim of the project is to set-up a center of scientific excellence in the Central-Eastern region of Cuba for traditionally used bioactive plants and their metabolites.

Researcher(s)

• Promoter: Cos Paul
• Co-promoter: De Winter Hans
• Co-promoter: Pieters Luc

Research team(s)

• Laboratory for Microbiology, Parasitology and Hygiene (LMPH)

Project type(s)

• Research Project

Abstract

The functional levels of a biological system include the genome, transcriptome, proteome and metabolome, and the latter is considered as most representative of the phenotype. Tumors develop tumor-specific metabolism that endows them with more predominant proliferation, independent of tissue type, while retaining some metabolic traits of the tissue from which they originated. Exploring the cancer metabolome is considered as a promising way to reveal phenotypic changes related to cancer, and to establish specific biomarkers that may be used in screening for diagnostic and prognostic purposes. Many cancers have a higher cure rate if detected in early stages. Metabolomics is an analytical tool used in conjunction with pattern recognition approaches and bioinformatics to detect metabolites and follow their changes in biofluids or tissue. 1H-NMR spectroscopy and LCMS are the two major spectroscopic techniques used in metabolic analysis. This project focuses on colorectal cancer (CRC). It has been established that, apart from plasma, peripheral blood mononuclear cells (PBMC) may provide potential prognostic biomarkers for disease, and may constitute an excellent starting point for early CRC biomarker discovery. Therefore, the main objective of this project is the metabolomics analysis by 1H-NMR and LCMS of plasma and PBMC from diagnosed CRC patients in various stages and healthy controls, and to establish a set of early biomarkers for this cancer type.

Researcher(s)

• Promoter: Apers Sandra
• Promoter: Pieters Luc
• Co-promoter: Lemière Filip
• Co-promoter: Peeters Marc
• Co-promoter: Pieters Luc
• Fellow: Custers Deborah

Research team(s)

Project type(s)

• Research Project

Abstract

The project aims to establish a multidisciplinary reference platform at CIDEM with improved capacity (infrastructure+ know-how/training) in natural drug research and development, which integrates preparation of plant extracts, extraction and purification, analytical and structural characterization, molecular pharmacological evaluation and design and evaluation of appropriate systems of drug delivery, which allows pharmaceutical and pharmacological studies of phytomedicinal and nutraceutical products according to international standards, to stimulate the use of natural products in the National System of Health (NSH) in Cuba.

Researcher(s)

• Promoter: Apers Sandra
• Promoter: Pieters Luc
• Co-promoter: Kiekens Filip
• Co-promoter: Pieters Luc
• Co-promoter: Vanden Berghe Wim

Research team(s)

Project type(s)

• Research Project

Abstract

A novel approach is presented in order to characterize new lead compounds from natural sources. Many natural products are pro-drugs that are metabolized and activated after oral administration. Nevertheless, this aspect is usually overlooked when searching for new therapeutic agents using classical approaches. In this project, Salix spp. (willow bark) and Filipendula ulmaria (meadowsweet) were selected as case studies for the characterization of new leads for anti-inflammatory drugs.

Researcher(s)

• Promoter: Pieters Luc
• Co-promoter: Apers Sandra
• Co-promoter: Hermans Nina
• Fellow: Van der Auwera Anastasia

Research team(s)

Project type(s)

• Research Project

Abstract

The main goal of the MediHealth project is to introduce a novel approach for the discovery of active agents of food plants from Mediterranian diet and other global sources to promote healthy ageing. This will be achieved through an extended and well-balanced scheme of researcher's secondments between 5 universities and 4 enterprises from EU and associated countries as well as 4 universities from Third countries.

Researcher(s)

• Promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

During previous investigations in the host laboratory it has been found that several classes of natural products, i.e. polymethoxyflavones, biflavonoids, xanthones and quinazoline alkaloids, exhibited AGEs inhibiting properties. AGEs (or Advanced Glycation Endproducts) are implicated in many age-related chronic diseases and in protein ageing, and are associated with diabetic complications, atherosclerosis, neurodegenerative diseases, cancer and the normal ageing processes. AGEs have been found to induce autophagy, a favourable subcellular process contributing to cellular homeostasis and adaptation to stress by removing damaged or unwanted intracellular material. Similar to AGEs, autophagy has been associated with different pathological conditions including heart disease, cancer and neurodegeneration. Autophagy is stimulated in atherosclerosis and in oxidative stress conditions. Therefore, AGEs inhibition and modulation of autophagy were selected as targets to be evaluated and to establish structure-activity relationships for the product classes mentioned above. Both AGEs inhibition and modulation of autophagy are relatively new targets in natural product research. AGEs inhibitors and inducers of autophagy, or a combination of both, may be potentially useful products against degenerative diseases in a broad sense, such as the ones mentioned above.

Researcher(s)

• Promoter: Pieters Luc
• Co-promoter: Apers Sandra
• Fellow: Velichkova Stefaniya

Research team(s)

Project type(s)

• Research Project

Abstract

In this project four medicinal plants, more in particular Nymphoides indica, Kickxia ramosissima, Cordia dichotoma and Ferula narthex, traditionally used in Pakistan in two different therapeutic areas, i.e. for antimicrobial purposes or against diabetes and its complications, will be phytochemically and pharmacologically investigated. Constituents will be isolated, identified by means of spectroscopic methods, and evaluated in a range of pharmacological assays related to antimicrobial and antidiabetic activity.

Researcher(s)

• Promoter: Pieters Luc
• Fellow: Amin Adnan

Research team(s)

Project type(s)

• Research Project

Abstract

This project represents a research contract awarded by the University of Antwerp. The supervisor provides the Antwerp University research mentioned in the title of the project under the conditions stipulated by the university.

Researcher(s)

• Promoter: Augustyns Koen
• Co-promoter: Apers Sandra
• Co-promoter: Cos Paul
• Co-promoter: Delputte Peter
• Co-promoter: De Meester Ingrid
• Co-promoter: De Winter Hans
• Co-promoter: D'Haese Patrick
• Co-promoter: Hermans Nina
• Co-promoter: Kiekens Filip
• Co-promoter: Lambeir Anne-Marie
• Co-promoter: Maes Louis
• Co-promoter: Pieters Luc
• Co-promoter: Van Der Veken Pieter
• Fellow: Joossens Jurgen
• Fellow: Pauwels Maxim
• Fellow: Verhoeven Kristien

Research team(s)

• Medicinal Chemistry (UAMC)

Project type(s)

• Research Project

Abstract

Many natural products are pro-drugs that are metabolized and activated after oral administration, but this is usually overlooked when searching for new lead compounds. Here Filipendula ulmaria (meadowsweet) and Herniaria hirsuta are selected as case studies for the characterization of new leads for anti-inflammatory drugs, and drugs for nephrolithiasis. An LC-MS and 1H-NMR platform will be used for the fast metabolomic profiling of plant extracts. Secondly, a dialysis model simulating human gastro-intestinal (GI) metabolization will be applied to activate potential pro-drugs. In addition, the dialysate containing the GI metabolites will be treated with microsomal S9 fractions to mimic liver metabolization. The resulting metabolized samples (before and after S9 treatment) will be profiled in the same LC-MS and 1H-NMR platform, and compared with the original profiles. At the same time all extracts and metabolized extracts will be pharmacologically evaluated in a range of in vitro assays related to anti-inflammatory and anti-nephrolithiasis properties, and all data will be analyzed in a metabolomics approach using multivariate data analysis in order to characterize the pharmacologically active constituents and their metabolites as new lead compounds.

Researcher(s)

• Promoter: Pieters Luc
• Co-promoter: Apers Sandra
• Co-promoter: Hermans Nina

Research team(s)

Project type(s)

• Research Project

Abstract

A novel approach is presented in order to characterize new lead compounds from natural sources. Many natural products are pro-drugs that are metabolized and activated after oral administration. Nevertheless, this aspect is usually overlooked when searching for new therapeutic agents using classical approaches. In this project, the Nauclea pobeguinii tree, Herniaria hirsuta herb, Salix spp. (willow bark) and Filipendula ulmaria (meadowsweet) were selected as case studies for the characterization of new leads for antimalarial, anti-nephrolithiasis, and anti-inflammatory drugs. LC-MS (Liquid Chromatography – Mass Spectrometry) and NMR (Nuclear Magnetic Resonance Spectroscopy) platforms will be established for the fast metabolic profiling of plant extracts, prepared using comprehensive extraction methods to cover the full range of constituents. Secondly, a gastro-intestinal dialysis model (GIDM) simulating human GI metabolization, will be applied in order to activate potential pro-drugs. In addition, the dialysate containing the GI metabolites will be treated with microsomal S9 fractions to mimic liver metabolization. The resulting metabolized samples (before and after S9 treatment) will be profiled using the same LC-MS and NMR platforms, and compared with the original profiles. At the same time all extracts and metabolized extracts will be pharmacologically evaluated in a range of in vitro assays related to antimalarial, anti-nephrolithiasis and anti-inflammatory properties. Pharmacological and chromatographic/ phytochemical data will be analyzed in a metabolomics approach using multivariate data analysis in order to identify pharmacologically active constituents or metabolites. Targeted isolation and final pharmacological evaluation in vitro and in vivo will yield new lead compounds against malaria, nephrolithiasis and inflammatory diseases.

Researcher(s)

• Promoter: Pieters Luc
• Co-promoter: Apers Sandra
• Co-promoter: Covaci Adrian
• Co-promoter: Hermans Nina

Research team(s)

Project type(s)

• Research Project

Abstract

Many natural products are pro-drugs that are metabolized and activated after oral administration. Nevertheless this aspect is usually overlooked when searching for new lead compounds for therapeutic agents. In this project Filipendula ulmaria (meadowsweet) and Herniaria hirsuta have been selected as case studies for the characterization of new leads for anti-inflammatory drugs, and drugs for nephrolithiasis. An LC-MS and 1H-NMR platform will be used for the fast metabolomic profiling of plant extracts, prepared using comprehensive extraction methods to cover the full range of constituents. Secondly, the platform will be extended with a dialysis model simulating human gastro-intestinal (GI) metabolization, which will be applied to activate potential pro-drugs. In addition, the dialysate containing the GI metabolites will be treated with microsomal S9 fractions to mimic liver metabolization. The resulting metabolized samples (before and after S9 treatment) will be profiled in the same LC-MS and 1H-NMR platform, and compared with the original profiles. At the same time all extracts and metabolized extracts will be pharmacologically evaluated in a range of in vitro assays related to anti-inflammatory and anti-nephrolithiasis properties. Pharmacological and chromatographic / phytochemical data will be analyzed in a metabolomics approach using multivariate data analysis in order to characterize the pharmacologically active constituents and their metabolites as new lead compounds.

Researcher(s)

• Promoter: Pieters Luc
• Co-promoter: Apers Sandra
• Co-promoter: Covaci Adrian
• Co-promoter: Laukens Kris
• Fellow: Bijttebier Sebastiaan

Research team(s)

Project type(s)

• Research Project

Abstract

The aim of the project is to evaluate extracts of South African plants as detoxifying agents against the mutagenic effects of mycotoxins using in vitro bioassays. Such plant extracts may be added to feeds and foods as a chemo-preventive measure against the genotoxic effects of mycotoxins, particularly aflatoxins.

Researcher(s)

• Promoter: Pieters Luc
• Co-promoter: Apers Sandra
• Co-promoter: Verschaeve Luc

Research team(s)

Project type(s)

• Research Project

Abstract

This project represents a formal research agreement between UA and on the other hand the Hercules Foundation. UA provides the Hercules Foundation research results mentioned in the title of the project under the conditions as stipulated in this contract.

Researcher(s)

• Promoter: Maes Bert
• Co-promoter: Abbaspour Tehrani Kourosch
• Co-promoter: Augustyns Koen
• Co-promoter: Herrebout Wouter
• Co-promoter: Pieters Luc
• Co-promoter: Tavernier Serge
• Co-promoter: Van Der Veken Pieter

Research team(s)

• Organic synthesis (ORSY)

Project type(s)

• Research Project

Abstract

The main goal of this project is to identify the bioactive phytochemicals (focusing on AGEs and ALEs inhibitors) from selected plants, and to investigate the mechanisms of the inhibition. Previous studies on Japanese food habits, in particularly from Okinawan islands, have shown that some local plants consumed regularly are very rich in bioactive phytochemicals and are supposed to contribute to longevity of the local people. Some reports on Nepalese herbs are also revealing the same. Based on pubished evidence that supports the presence of phytochemicals in food from Japan, in particular Okinawa, and assessment of the traditional usages and reported studies on Nepalese herbs, a series of 20 plant species has been selected for the intended study.

Researcher(s)

• Promoter: Pieters Luc
• Fellow: Upadhyay Atul

Research team(s)

Project type(s)

• Research Project

Abstract

Mycotoxins cause animal diseases and decrease production of eggs, milk and meat. Genotoxic or mutagenic effects are amongst the important adverse effects. A mutagenic compound is most often also carcinogenic. Aflatoxins are one of the important mycotoxins and amongst the most potent carcinogens. Other mycotoxins may also be mutagenic and carcinogenic. In this project we intend to evaluate extracts of South African plants as detoxifying agents against the mutagenic effects of mycotoxins. Preliminary research found this to be a very realistic approach which may provide identification of protective substances that can be added to feeds and foods as chemo-preventive measures against the genotoxic/carcinogenic effects of mycotoxins. Extracts of the plants will be prepared and antimutagenic effects will be tested against mycotoxin (such as aflatoxin B1, fumonisin and ochratoxin)-induced mutagenicity. For this, bacteria (Ames test and Vitotox test) or human cell lines (comet assay and micronucleus/cytome test) will be exposed to the toxin alone, and in the presence of extract. The mutagenicity response of both treatments will be compared. The most promising extracts will be fractionated and fractions will again be tested until active compounds are purified. The active compounds will then be quantified in the original extracts, and the well-characterised extracts will be evaluated in vivo in rats for their protective effects against aflatoxin-induced toxicity.

Researcher(s)

• Promoter: Pieters Luc
• Co-promoter: Apers Sandra
• Co-promoter: Hermans Nina
• Co-promoter: Verschaeve Luc

Research team(s)

Project type(s)

• Research Project

Abstract

The general aim of this project is to improve understanding of immune and oxidative stress aberrancies in ADHD and to evaluate the effects of supplementation with Pinus pinaster bark extract on behaviour and comorbid symptoms and on immune, oxidative stress and antioxidant biomarkers, as compared to placebo, no intervention and MPH treatment.

Researcher(s)

• Promoter: Hermans Nina
• Co-promoter: Ceulemans Berten
• Co-promoter: Pieters Luc
• Fellow: Verlaet Annelies

Research team(s)

Project type(s)

• Research Project

Abstract

The general aim of this project is to combine the LC-MS and LC-NMR platform available in the Laboratory of Pharmacognosy and Pharmaceutical Analysis (Department of Pharmaceutical Sciences, University of Antwerp) for the characterisation of cyclopeptide alkaloids, a promising class of natural products, from selected plant sources, followed by their targeted isolation, and establishment of structure-activity relationships in several pharmacological models.

Researcher(s)

• Promoter: Pieters Luc
• Co-promoter: Hermans Nina
• Fellow: Tuenter Emmy

Research team(s)

Project type(s)

• Research Project

Abstract

The aim of this project is the isolation, structure elucidation and phytochemical analysis of biologically active constituents in some selected medicinal plants from Pakistan. Focus of the research project will be on plants used for antimicrobial purposes (against infectious diseases), and on plants used by diabetic patients to relieve diabetic complications or to ameliorate the disease. This work may result in the characterisation of lead compounds for new therapeutic agents, and may provide a scientific basis for the traditional use of the plants investigated.

Researcher(s)

• Promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

The general aim of this project is to improve understanding of immune and oxidative stress aberrancies in ADHD and to evaluate the effects of supplementation with Pinus pinaster bark extract on behaviour and comorbid symptoms and on immune, oxidative stress and antioxidant biomarkers, as compared to placebo, no intervention and MPH treatment.

Researcher(s)

• Promoter: Hermans Nina
• Co-promoter: Pieters Luc
• Fellow: Verlaet Annelies

Research team(s)

Project type(s)

• Research Project

Abstract

Advanced glycation endproducts (AGEs) are a heterogeneous group of compounds that have been implicated in diabetes-related complications. The present project will investigate AGEs inhibition by constituents from two plants, Momordia charantia (Bitter lemon) and Citrus depressa. This study will identify potent anti-AGEs natural compounds, which may serve as lead compounds in the design of new drugs against diabetes and its complications.

Researcher(s)

• Promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

The general aim of this project is to combine the LC-MS and LC-NMR platform available in the Laboratory of Pharmacognosy and Pharmaceutical Analysis (Department of Pharmaceutical Sciences, University of Antwerp) for the characterisation of cyclopeptide alkaloids, a promising class of natural products, from selected plant sources, followed by their targeted isolation, and establishment of structure-activity relationships in several pharmacological models.

Researcher(s)

• Promoter: Pieters Luc
• Co-promoter: Apers Sandra
• Co-promoter: Hermans Nina
• Fellow: Tuenter Emmy

Research team(s)

Project type(s)

• Research Project

Abstract

In this project the biologically active constituents from two medicinal plants from Pakistan, more in particular Ziziyphus oxyphylla (Rhamnaceae) and Cedrela serrata (Meliaceae) will be investigated. Their constituents will be chromatographically isolated, identified by spectroscopic means, and pharmacolligically evaluted in various models.

Researcher(s)

• Promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

This project comprises the identification of the active metabolites of selected natural products with a proven biological activity. The focus will be on Cranberry (Vaccinium macrocarpon) which is used against urinary tract infections, and the Congolese medicinal plant Nauclea pobeguinii, which showed promising activity against malaria in vitro as well as in vivo. For both plants, in vivo activity may be attributed to the formation of biologically active metabolites. The identification of these active metabolites involves the integrated application of in vitro and in vivo test systems with up-to-date technologies such as LC-MS (Liquid Chromatography – Mass Spectrometry) and LC-NMR (Liquid Chromatography – Nuclear Magnetic Resonance spectroscopy) combined with modern information technology such as MVA (multivariate data analysis) to process large amounts of data. These investigations on metabolites of selected natural products with a proven biological activity represent a challenging research field, whereas the successful completion of the submitted proposal might also lead to the characterisation of potential lead compounds for new drugs.

Researcher(s)

• Promoter: Apers Sandra
• Co-promoter: Covaci Adrian
• Co-promoter: Hermans Nina
• Co-promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

This project will focus on the potential use of strictosamide (isolated from the bark of Nauclea pobeguinii) or its metabolites as a pure chemical entity to be used as an active pharmaceutical ingredient against malaria.

Researcher(s)

• Promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

This project represents a research agreement between the UA and on the onther hand IWT. UA provides IWT research results mentioned in the title of the project under the conditions as stipulated in this contract.

Researcher(s)

• Promoter: Pieters Luc
• Fellow: Capistrano I. Rica

Research team(s)

Project type(s)

• Research Project

Abstract

This project represents a formal research agreement between UA and on the other hand the Flemish Public Service. UA provides the Flemish Public Service research results mentioned in the title of the project under the conditions as stipulated in this contract.

Researcher(s)

• Promoter: Apers Sandra
• Co-promoter: Augustyns Koen
• Co-promoter: Maes Bert
• Co-promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

This project represents a formal research agreement between UA and on the other hand a private institution. UA provides the private institution research results mentioned in the title of the project under the conditions as stipulated in this contract.

Researcher(s)

• Promoter: Apers Sandra
• Co-promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

A technology platform is developed using LC-MS-DAD and LC-NMR for the metabolomic profiling of medicinal plants. The isolation of only the most promising products, followed by their pharmacological evaluation, may result in lead compounds for new drugs.

Researcher(s)

• Promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

In this project a technology platform is developed using LC-MS-DAD and LC-NMR for the metabolomic profiling of promising medicinal plants (in this project Nauclea pobeguinii) in order to characterise secondary metabolites in their complex plant matrix. The isolation of only the most promising products, followed by their biological and pharmacological evaluation, may result in new lead compounds for therapeutic agents.

Researcher(s)

• Promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

This project represents a research contract awarded by the University of Antwerp. The supervisor provides the Antwerp University research mentioned in the title of the project under the conditions stipulated by the university.

Researcher(s)

• Promoter: Augustyns Koen
• Co-promoter: Dommisse Roger
• Co-promoter: Maes Bert
• Co-promoter: Pieters Luc

Research team(s)

• Medicinal Chemistry (UAMC)

Project type(s)

• Research Project

Abstract

Due to the growing interest and use of medicinal plants new companies distributing these products arise rapidly and preparations sold in the US or Asia are freely available via the internet. This kind of non-controlled exposure, i.e. with respect to the indication, dosing, contra-indication and side effects, is questionable. In order to maintain its current positive market position and to be a worthy addition to the Western medicine, phytotherapy should be scientifically sustained and of high quality. The proposed project, i.e. the investigation of the efficacy and non-toxicity and analysing the quality of these products, is of big importance for public health.

Researcher(s)

• Promoter: Apers Sandra
• Co-promoter: Pieters Luc
• Fellow: Theunis Mart

Research team(s)

Project type(s)

• Research Project

Abstract

Natural hybridisation of plant species comprises a part of the mechanisms contributing to the evolution and diversification of species. By this mechanism new secondary metabolites or new combinations of existing secondary metabolites can be created. A major step in making hybrids is the selection of the desired fusion products. In order to do this a new method improving the capacity of the selection will be investigated. Hybrid cell cultures will be analysed with respect to their growth, saponin production and composition, and genome organisation. The aim is to obtain high producing cell cultures delivering preferably the most active saponins as major compounds.

Researcher(s)

• Promoter: Apers Sandra
• Co-promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

The first objective of this research project is to determine the in vivo antioxidant profile of plant polyphenols after oral supplementation in animals of some selected standardised plant preparations. However, prior to starting this in vivo evaluation, it is essential to extend the existing battery of assays of the research group with additional methods for the assessment of oxidative damage to other endogenous biomolecules than lipids, such as DNA and proteins. The second objective is the development of an in vitro continuous dialysis model with a colon-phase to study the metabolisation by gut flora of the same selected plant preparations and their polyphenolic constituents, the absorption and the antioxidative properties of their metabolites. The presence of the metabolites formed in the in vitro model will be checked in plasma of the laboratory animals. The in vitro antioxidative profile of the metabolites will be compared with the reduction of in vivo parameters of oxidative stress, in order to validate this in vitro dialysis model. In this way the in vitro dialysis model with colon-phase may be, at least in part, a substitute for experiments in laboratory animals in the future.

Researcher(s)

• Promoter: Pieters Luc
• Co-promoter: Apers Sandra
• Co-promoter: Hermans Nina

Research team(s)

Project type(s)

• Research Project

Abstract

Researcher(s)

• Promoter: Pieters Luc
• Co-promoter: Totte Jozef

Research team(s)

Project type(s)

• Research Project

Abstract

The principal anti-oxidative components of Pueraria lobata, Cynara scolymus en Olea europaea, plants containing high amounts of polyphenols, will be characterised and their in vitro anti-oxidative profile established. Analytical methods will be developed and validated in order to obtain test preparations standardised on these active components. The research project will be completed by the investigation of the in vivo anti-oxidative effects of these preparations in a diabetic rat model.

Researcher(s)

• Promoter: Apers Sandra
• Co-promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

This project concerns structural investigation research on biologically active plant metabolites and carbonaceous aerosols using mass spectrometric methodology based on a soft ionization technique, i.e. electrospray ionization (ESI), in combination with collision-induced dissociation (CID) and tandem mass spectrometric (MS/MS) techniques. Methods will be developed for the determination of the strength of non-covalent drug-haem interactions and for the characterization of plant metabolites in crude extracts with potential antimalarial activity, as well as for the structural characterization of biologically active plant metabolites that will be isolated from medicinal plants and of polar organic molecules in carbonaceous aerosols that are formed through photo-oxidation of isoprene. This project deals with : 1) investigation of the non-covalent interaction between plant metabolites with the potential antiplasmodial activity and haem; 2) structural characterization of unknown biologically active plant metabolites isolated from medicinal plants; 3) structural characterization of oxidation products of isoprene in smog chamber and natural biogenic aerosols.

Researcher(s)

• Promoter: Claeys-Maenhaut Magda
• Co-promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

The key objective of the Combiplan project is to establish a combinatorial biosynthesis platform in plants that will allow the semi-rational combinatorial engineering of the biosynthesis of existing and novel secondary metabolites in plant cell tissue cultures. To obtain proof of concept, the research strategy designed will be applied to the metabolite class of the triterpene saponins.

Researcher(s)

• Promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

Based on a lead compound active against Leishmaniasis, which belongs to the class of the dihydrobenzofuran lignans, characterised in our laboratory, a more detailed investigation of the structure-activity relationship of these compounds will be carried out. Specific up-to-date methods for the synthesis of lignans, as well as QUASAR (Quantitative Structure-Activity Relationship) techniques, will be used.

Researcher(s)

• Promoter: Pieters Luc
• Fellow: Juhasz Laszlo

Research team(s)

Project type(s)

• Research Project

Abstract

Researcher(s)

• Promoter: Hermans Nina
• Promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

Parasitic infections such as malaria, trypanosomiasis and leishmaniasis still make a lot of victims every year, especially in developing countries. The aim of this project is to investigate new lead compounds for drugs against these diseases using a multidisciplinary approach: characterisation of new leads from medicinal plants; further investigations of indoloquinoline derivatives, an existing lead; and design of inhibitors of trypanothionsynthetase and prolyloligopeptidase.

Researcher(s)

• Promoter: Pieters Luc
• Co-promoter: Augustyns Koen
• Co-promoter: Haemers Achiel
• Co-promoter: Lemiere Guy
• Co-promoter: Vlietinck Arnold

Research team(s)

Project type(s)

• Research Project

Abstract

Cancer claims millions of lives each year. On a world wide basis, cancer represents the single largest cause of death in both men and women. Cancer chemoprevention, a term coined by Sporn in 1976, can be defined as the prevention, inhibition, or reversal of carcinogenesis by administration of one ore more chemical entities, either as individual drugs or as naturally occurring constituents of the diet. Because carcinogenesis is a multistage process there is considerable opportunity for intervention and a number of potential targets for chemoprevention have recently been identified. Based upon the time period during which agents appear to exhibit activity in animal models of carcinogenesis, the major types of chemopreventive agents are: inhibitors of carcinogen formation, 'blocking agents' and 'suppressing agents'. Blocking agents, i.e. inhibitors of tumor initiation, can act by inhibition of carcinogen uptake, inhibition of formation or activation of carcinogen, deactivation or detoxification of carcinogen, preventing carcinogen binding to DNA, or enhancing the level of fidelity of DNA repair. Chemopreventive activity by antioxidant agents includes scavenging reactive electrophiles, scavenging oxygen radicals, and inhibiting arachidonic acid metabolism. Suppressing agents can be described more specifically as inhibitors of tumor promotion/progression. Antiproliferation/ antiprogression activities include, among others, modulation of hormonal and growth factor activity, induction of programmed cell death (apoptosis), and inhibition of angiogenesis. Many classes of natural products, having anti-oestrogenic, anti-inflammatory, antioxidative and/or anti-angiogenic activity, such as carotenoids, isothiocyanates, terpenoids, polyphenols, flavonoids, isoflavones, plant sterols, saponins, lignans and coumarins have shown a great deal of promise. The rationale for this research project is to search molecular evidence for chemopreventive activities shown by three medicinal plants and to link these activities with and establish structure activity relationships for their known and unknown constituents. The work will be focused on, but not limited to, types of constituents for which, based on previous reports, chemopreventive properties can reasonably be expected, but for which the mechanisms of action is mostly unknown.

Researcher(s)

• Promoter: Pieters Luc
• Fellow: Apers Sandra

Research team(s)

Project type(s)

• Research Project

Abstract

Angiogenesis or the development of new bloodvessels from existing microvascular tissue is a fundamental aspect of many fysiological and pathological processes. Angiogenesis is of fundamental importance in the growth and metastasis of tumors and in chronic inflammatory diseases. Antiangiogenic therapeutics are therefore of potential use in cancer treatment and arthritis. The design and development of antiangiogenic therapeutics in this project will be done either on a rational way, either with at random control of chemical libraries. The rational approach will be based on the design of inhibitors of matrix metalloproteinases (MMP) or of urokinase type plasminogen activator (uPA). We will use ligand-based drug design based on the structure of known inhibitors and substrates and based on the enzymatic mechanism of the target. Since the 3D structure of the targets is known, we will also use structure-based drug desing. The at random approach will be based on the control of antiangiogenic activity of a library of chemical compounds isolated from nature. Especially certain saponins and dihydrobenzofuran lignans with promising acitvities will be further investigated

Researcher(s)

• Promoter: Augustyns Koen
• Co-promoter: Haemers Achiel
• Co-promoter: Pieters Luc

Research team(s)

• Medicinal Chemistry (UAMC)

Project type(s)

• Research Project

Abstract

In this project some classes of biologically active glycosidic compounds from medicinal plants are studied, more particularly Maesa lanceolata, Aleurites moluccana, Ipomoea involucrata, Morinda moroindoides and Morinda lucida. The structure of isolated compounds will be elucidated using spectroscopic techniques, especially inverse NMR methods, and their activity investigated in different models (antiviral activity, including HIV; antiangiogenesis), in order to establish structure-activity relationships.

Researcher(s)

• Promoter: Pieters Luc
• Fellow: Apers Sandra

Research team(s)

Project type(s)

• Research Project

Abstract

Some classes of biologically active glycoside compounds, i.e. spaonins, glycoresins and glycosidic iridoid lactones will be isolated form medicinal plants, identified by means of spectroscopic methods, especially micro-inverse NMR techniques and evaluated in various bioassays. Structure-activity relationships will be established in order to characterize potential lead compounds for the development of new drugs, especially for antiviral and antitumoral therapy.

Researcher(s)

• Promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

Preliminary investigations have resulted in the selection of number of plants showing an antiviral (including HIV) and/or an immunomodulating activity, including Maesa lanceolata, Clermontia arborescens, and Aspilia pluriseta. The active components of these plants will be identified using NMR and MS-techniques, and their activity will be investigated more in detail.

Researcher(s)

• Promoter: Pieters Luc
• Fellow: Apers Sandra

Research team(s)

Project type(s)

• Research Project

Abstract

The proposed research programme deals with mass spectrometric studies on the structural characterisation of biomolecules which will remain of fundamental biological interest and of functional dyes which are important for their material properties. The molecules which will be studied include lipide, plant glycoconjugates, peptides, proteins and aromatic oligomers and polymers. The objectives are to examine in detail and systematically the unimolecular chemistry of some of these compounds in the gas phase.

Researcher(s)

• Promoter: Claeys-Maenhaut Magda
• Co-promoter: Geise Herman
• Co-promoter: Haemers Achiel
• Co-promoter: Pieters Luc
• Co-promoter: Vlietinck Arnold

Research team(s)

Project type(s)

• Research Project

Abstract

Preliminary investigations have resulted in the selection of number of plants showing an antiviral (including HIV) and/or an immunomodulating activity, including Maesa lanceolata, Clermontia arborescens, and Aspilia pluriseta. The active components of these plants will be identified using NMR and MS-techniques, and their activity will be investigated more in detail.

Researcher(s)

• Promoter: Pieters Luc
• Fellow: Apers Sandra

Research team(s)

Project type(s)

• Research Project

Abstract

Pavetta owariensis and Harrisonia abyssinica are two West-African plants containing schistosomicidal and molluscicidal constituents. These will be isolated and identified, and the plant extracts will be standardised for these components.

Researcher(s)

• Promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

Biologically active natural compounds from higher plants are used as prototype for the synthesis of analogues, to improve the activity, to study structure-activity relationship, in order to obtain potential new drugs. Structure of isolated and synthetic compounds will be elucidated using NMR spectroscopy.

Researcher(s)

• Promoter: Pieters Luc
• Co-promoter: Haemers Achiel
• Co-promoter: Vlietinck Arnold

Research team(s)

Project type(s)

• Research Project

Abstract

HIV is a retrovirus which causes AIDS, resulting in a suppression of the immune system. Anti-HIV agents as well as immunostimulants have a therapeutical potential. The aim of this project is the isolation and structure elucidation of tannins and polysaccharides as potential new immunostimulants and/or anti-HIV agents.

Researcher(s)

• Promoter: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

This research project deals with the biologically guided isolation of natural compounds with chemotherapeutic, antimutagenic, antitumoral, immunomodulating and enzym-inhibiting properties, their structure elucidation by means of spectroscopic techniques and their development as prototypes of potential new drugs.

Researcher(s)

• Promoter: Vlietinck Arnold
• Fellow: Pieters Luc

Research team(s)

Project type(s)

• Research Project

Abstract

Researcher(s)

• Promoter: Vlietinck Arnold
• Fellow: Pieters Luc

Research team(s)

Project type(s)

• Research Project