11 research outputs found
PeBiToSensâą: A Platform for PBT Screening of Fragrance Ingredients Without Animal Testing
The determination of persistence (P), bioaccumulation (B) and toxicity (T) plays a central role in the environmental assessment of chemicals. Persistence is typically evaluated via standard microbial biodegradation tests. Bioaccumulation refers to the accumulation of chemicals
in organisms and is usually assessed in fish exposed to the test chemical. Toxicity is determined at three trophic levels, with fish toxicity as the highest trophic level assessed. Thus, animal tests are classically needed for both B and T assessment. In vitro systems based on fish
liver cells or liver S9 fractions ('RT-S9 assay') have been recently adopted by OECD to measure the biotransformation rates for the chemicals for B assessment. Biotransformation drives clearance from the body and reduces bioaccumulation. For T assessment, an assay based on in vitro
toxicity on fish gill cells has been established ('RTgill-W1 assay'). Here we summarize our findings indicating that these tests are highly predictive for fragrance ingredients, and show with two case studies of our latest new registered substances how we apply these tests in particular during
development and also for chemical registration. This platform of tests (PeBiToSensâą) could fully replace animal tests in ecotoxicological assessment and is key in the Givaudan Safe by Designâą approach to develop safer and environmentally compatible novel fragrance ingredients
Liming effects on the chemical composition of the organic surface layer of a mature Norway spruce stand (Picea abies [L.] Karst.)
11 pages, 8 figures, 3 tables, 58 references.The application of lime in a mature Norway spruce (Picea abies [L.] Karst.) forest in southern Germany induced major changes in the
activity of soil organisms and root growth. Since this may inïŹuence the chemical compostion of the soil organic matter (SOM) of the organic
surface layer, its composition and changes due to the treatment were examined in this study.
Fine roots of Norway spruce have a relatively low content of extractable lipids, a low alkyl C content (13C CPMAS NMR) and a high ratio
of non-cellulosic to cellulosic carbohydrates (NC/CC, carbohydrate determination by MBTH and gas chromatography analyses) as compared
to needles. Furthermore, they show high ratios of suberin/cutin compounds (thermally assisted hydrolysis and methylation, (THM)) and high
ratios of eicosanic acid/phytadiene I in their lipid extracts (pyrolysis-GC/MS).
Liming (4 t ha21
dolomite) of a Norway spruce organic surface layer decreased the proportion of alkyl C, the alkyl C/O-alkyl C ratio, and
the content of extractable lipids. The NC/CC ratio and the abundance of suberin relative to cutin components increased. The contribution of
the chlorophyll component phytadiene I decreased in relation to eicosanic acid. These changes are attributed to increased ïŹne root formation
in the organic layer after liming. Furthermore, the presence of less degraded lignin (THM, peak ratio of 3,4-dimethoxybenzoic acid, methyl
ester/3,4-dimethoxy-benzaldehyde) on the limed plot is explained by the increased input of relatively fresh ïŹne root material. On the other
hand, the decrease in the carbon-to-nitrogen ratio may be attributed to the higher microbial activity after liming.This part of the Hoeglwald
research was supported by the Ministry for Education
and Science, Germany, and by the European Community
activity Large-Scale Facility Wageningen NMR Centre
(ERBFMGECT950066).Peer reviewe
Natural Compound Library Screening Identifies New Molecules for the Treatment of Cardiac Fibrosis and Diastolic Dysfunction.
High-throughput natural compound library screening identified 15 substances with antiproliferative effects in human cardiac fibroblasts. Using multiple in vitro fibrosis assays and stringent selection algorithms, we identified the steroid bufalin (from Chinese toad venom) and the alkaloid lycorine (from Amaryllidaceae species) to be effective antifibrotic molecules both in vitro and in vivo, leading to improvement in diastolic function in 2 hypertension-dependent rodent models of cardiac fibrosis. Administration at effective doses did not change plasma damage markers or the morphology of kidney and liver, providing the first toxicological safety data. Using next-generation sequencing, we identified the conserved microRNA 671-5p and downstream the antifibrotic selenoprotein P1 as common effectors of the antifibrotic compounds
Natural Compound Library Screening Identifies New Molecules for the Treatment of Cardiac Fibrosis and Diastolic Dysfunction
BACKGROUND: Myocardial fibrosis is a hallmark of cardiac remodeling
and functionally involved in heart failure development, a leading cause
of deaths worldwide. Clinically, no therapeutic strategy is available that
specifically attenuates maladaptive responses of cardiac fibroblasts, the
effector cells of fibrosis in the heart. Therefore, our aim was to develop
novel antifibrotic therapeutics based on naturally derived substance library
screens for the treatment of cardiac fibrosis.
METHODS: Antifibrotic drug candidates were identified by functional
screening of 480 chemically diverse natural compounds in primary human
cardiac fibroblasts, subsequent validation, and mechanistic in vitro and
in vivo studies. Hits were analyzed for dose-dependent inhibition of
proliferation of human cardiac fibroblasts, modulation of apoptosis, and
extracellular matrix expression. In vitro findings were confirmed in vivo
with an angiotensin IIâmediated murine model of cardiac fibrosis in both
preventive and therapeutic settings, as well as in the Dahl salt-sensitive rat
model. To investigate the mechanism underlying the antifibrotic potential
of the lead compounds, treatment-dependent changes in the noncoding
RNAome in primary human cardiac fibroblasts were analyzed by RNA
deep sequencing.
RESULTS: High-throughput natural compound library screening
identified 15 substances with antiproliferative effects in human cardiac
fibroblasts. Using multiple in vitro fibrosis assays and stringent selection
algorithms, we identified the steroid bufalin (from Chinese toad venom)
and the alkaloid lycorine (from Amaryllidaceae species) to be effective
antifibrotic molecules both in vitro and in vivo, leading to improvement
in diastolic function in 2 hypertension-dependent rodent models of
cardiac fibrosis. Administration at effective doses did not change plasma
damage markers or the morphology of kidney and liver, providing the first
toxicological safety data. Using next-generation sequencing, we identified
the conserved microRNA 671-5p and downstream the antifibrotic
selenoprotein P1 as common effectors of the antifibrotic compounds.
CONCLUSIONS: We identified the molecules bufalin and lycorine as drug
candidates for therapeutic applications in cardiac fibrosis and diastolic
dysfunction
Natural Compound Library Screening Identifies New Molecules for the Treatment of Cardiac Fibrosis and Diastolic Dysfunction
BACKGROUND: Myocardial fibrosis is a hallmark of cardiac remodeling
and functionally involved in heart failure development, a leading cause
of deaths worldwide. Clinically, no therapeutic strategy is available that
specifically attenuates maladaptive responses of cardiac fibroblasts, the
effector cells of fibrosis in the heart. Therefore, our aim was to develop
novel antifibrotic therapeutics based on naturally derived substance library
screens for the treatment of cardiac fibrosis.
METHODS: Antifibrotic drug candidates were identified by functional
screening of 480 chemically diverse natural compounds in primary human
cardiac fibroblasts, subsequent validation, and mechanistic in vitro and
in vivo studies. Hits were analyzed for dose-dependent inhibition of
proliferation of human cardiac fibroblasts, modulation of apoptosis, and
extracellular matrix expression. In vitro findings were confirmed in vivo
with an angiotensin IIâmediated murine model of cardiac fibrosis in both
preventive and therapeutic settings, as well as in the Dahl salt-sensitive rat
model. To investigate the mechanism underlying the antifibrotic potential
of the lead compounds, treatment-dependent changes in the noncoding
RNAome in primary human cardiac fibroblasts were analyzed by RNA
deep sequencing.
RESULTS: High-throughput natural compound library screening
identified 15 substances with antiproliferative effects in human cardiac
fibroblasts. Using multiple in vitro fibrosis assays and stringent selection
algorithms, we identified the steroid bufalin (from Chinese toad venom)
and the alkaloid lycorine (from Amaryllidaceae species) to be effective
antifibrotic molecules both in vitro and in vivo, leading to improvement
in diastolic function in 2 hypertension-dependent rodent models of
cardiac fibrosis. Administration at effective doses did not change plasma
damage markers or the morphology of kidney and liver, providing the first
toxicological safety data. Using next-generation sequencing, we identified
the conserved microRNA 671-5p and downstream the antifibrotic
selenoprotein P1 as common effectors of the antifibrotic compounds.
CONCLUSIONS: We identified the molecules bufalin and lycorine as drug
candidates for therapeutic applications in cardiac fibrosis and diastolic
dysfunction