Using transcriptomics, proteomics and phosphoproteomics as new approach methodology (NAM) to define biological responses for chemical safety assessment.

Omic-based technologies are of particular interest and importance for hazard identification and health risk characterization of chemicals. Their application in the new approach methodologies (NAMs) anchored on cellular toxicity pathways is based on the premise that any apical health endpoint change must be underpinned by some alterations at the omic levels. In the present study we examined the cellular responses to two chemicals, caffeine and coumarin, by generating and integrating multi-omic data from multi-dose and multi-time point transcriptomic, proteomic and phosphoproteomic experiments. We showed that the methodology presented here was able to capture the complete chain of events from the first chemical-induced changes at the phosphoproteome level, to changes in gene expression, and lastly to changes in protein abundance, each with vastly different points of departure (PODs). In HepG2 cells we found that the metabolism of lipids and general cellular stress response to be the dominant biological processes in response to caffeine and coumarin exposure, respectively. The phosphoproteomic changes were detected early in time, at very low doses and provided a fast, adaptive cellular response to chemical exposure with 7-37-fold lower points of departure comparing to the transcriptomics. Changes in protein abundance were found much less frequently than transcriptomic changes. While challenges remain, our study provides strong and novel evidence supporting the notion that these three omic technologies can be used in an integrated manner to facilitate a more complete understanding of pathway perturbations and POD determinations for risk assessment of chemical exposures.

Landscape dynamic network biomarker analysis reveals the tipping point of transcriptome reprogramming to prevent skin photodamage.

Skin, as the outmost layer of human body, is frequently exposed to environmental stressors including pollutants and ultraviolet (UV), which could lead to skin disorders. Generally, skin response process to ultraviolet B (UVB) irradiation is a nonlinear dynamic process, with unknown underlying molecular mechanism of critical transition. Here, the landscape dynamic network biomarker (l-DNB) analysis of time series transcriptome data on 3D skin model was conducted to reveal the complicated process of skin response to UV irradiation at both molecular and network levels. The advanced l-DNB analysis approach showed that: (i) there was a tipping point before critical transition state during pigmentation process, validated by 3D skin model; (ii) 13 core DNB genes were identified to detect the tipping point as a network biomarker, supported by computational assessment; (iii) core DNB genes such as COL7A1 and CTNNB1 can effectively predict skin lightening, validated by independent human skin data. Overall, this study provides new insights for skin response to repetitive UVB irradiation, including dynamic pathway pattern, biphasic response, and DNBs for skin lightening change, and enables us to further understand the skin resilience process after external stress.

In vivo screening for anti-osteoporotic fraction from extract of herbal formula Xianlinggubao in ovariectomized mice.

BACKGROUND AND OBJECTIVES: Traditional Chinese Medicine (TCM) Fufang or formula Xianlinggubao (XLGB) is a prescribed TCM drug in China registered for prevention and treatment of osteoporosis. Fufang in TCM is comprised of a group of herbal compounds contributing in group to the treatment efficacy. The present study aims to identify the bioactive fraction(s) in XLGB extract that account(s) dominantly for its osteogenic effects. METHODS: The extract of XLGB formula was separated into three fractions using chromatography, i.e., XLGB-A, XLGB-B and XLGB-C. They were administrated to 4-month old ovariectomized (OVX) mice for 6 weeks to determine which bioactive fraction(s) were more effective for preventing OVX-induced bone loss evaluated by microCT, biomechanical testing and biochemical markers. The main peaks of the key fraction were identified using reference compounds isolated from the fraction. In addition, the effects of the composite compounds in XLGB-B on osteoblasts' proliferation and mineralization were evaluated in UMR 106 cells. RESULTS: XLGB-B with a yield of 13.0% from herbal Fufang XLGB was identified as the most potential one among the three fractions for prevention of OVX-induced bone loss confirmed with bone mass, bone microarchitecture, bone strength and bone turnover markers. Nine compounds in HPLC fingerprint were identified in the XLGB-B fraction, including phenylpropanoids from Herba Epimedii, terpenes from Radix Dipsaci and coumarins from Fructus Psoraleae. In addition, the identified compounds effectively promoted proliferation and/or mineralization of osteoblast-like UMR 106 cells in vitro. CONCLUSION: XLGB-B with defined phytochemical structures was screened as the key fraction that demonstrated preventive effects on OVX-induced bone loss in mice. The present study laid down a foundation towards a new generation of herbal Fufang characterized with "less herbal materials for achieving equal treatment efficacy" in development strategy of TCM for prevention of OVX-induced osteoporosis.

Rapid identification of chemical constituents in traditional Chinese medicine fufang preparation xianling gubao capsule by LC-linear ion trap/Orbitrap mass spectrometry.

The traditional Chinese medicine fufang preparation "Xian-Ling-Gu-Bao" capsule (XLGB), which is composed of six herbal medicines, is popularly used for the treatment of osteoporosis. A reliable and effective method using LC-linear ion trap (LTQ)/Orbitrap mass spectrometry for rapid screening and identification of chemical constituents in "Xian-Ling-Gu-Bao" capsule is described in this paper. Based on the UV spectrum, mass spectrum, and the chemical components isolated from the original plants of XLGB, 118 compounds were identified or tentatively characterized, including 58 flavonoid glycosides, six prenylated flavonones, five prenylated isoflavones, six prenylated chalcones, four xanthone C-glycosides, 13 saponins, eight phenolic acids, five coumarins, three lignans, three iridoids, five phenethyl alcohol glycosides, one tanshinone and one alkaloid. This work might be helpful for the quality control and further pharmacokinetic studies of XLGB, and provided a good example for the rapid identification of chemical constituents in traditional Chinese medicine fufang preparation. Moreover, the identification strategy for the linkages of sugar residues in flavonol O-glycosides was summarized in the study. The diagnostic fragment ions at m/z 185 [C12H9O2] and 157 [C11H9O], which distinguish C-6 and C-8 prenylated flavonoids, were reported for the first time.

Flavonol glycosides from Epimedium pubescens.

Five new flavonol glycosides (1, 3, 5-7) were isolated from the aerial parts of Epimedium pubescens Maxim., along with two known compounds, sagittasine C (2) and 4',5-dihydroxyl-8-(3,3-dimethylallyl)-flavonol 3-O-[ß-D-xylopyranosyl(1→3)-4-O-acetyl-α-L-rhamnopyranoside]-7-O-ß-D-glucopyranoside (4). The structures were elucidated on the basis of their 1D-, 2D-NMR, MS, UV and IR spectra data.

Design and synthesis of biphenyl derivatives as mushroom tyrosinase inhibitors.

Two new series of biphenyls, analogs of aglycone of natural product fortuneanoside E, were prepared using Suzuki-Miyaura cross-coupling and selective magnesium iodide demethylation/debenzylation, and their mushroom tyrosinase inhibitory activity was evaluated. Most of the 4-hydroxy-3,5-dimethoxyphenyl biphenyl compounds (series II, 20-36) were in general more active than 3,4,5-trimethoxyphenyl biphenyl compounds (series I, 1-19). Structure-activity relationships study showed that monosaccharide substituents, such as glucose, were not necessary and the presence of 4-hydroxy-3,5-dimethoxyphenyl moiety was crucial for inhibitory activity. Among the compounds synthesised, compound 21 (IC50=0.02 mM) was found to be the most active one, which exhibited an activity that was 7 times higher than that of fortuneanoside E (IC50=0.14 mM) and 10 times higher than that of arbutin (IC50=0.21 mM), known as potent tyrosinase inhibitors. The inhibition kinetics analyzed by Lineweaver-Burk plots revealed that compound 21 was a competitive inhibitor (Ki=0.015 mM).

Two new monoterpene glucosides from Paeonia lactiflora Pall.

Two new monoterpene glucosides, 4'-O-benzoylpaeoniflorin (1) and 4-O-galloylalbiflorin (2), were isolated from the 60% ethanol extract of the dried roots of Paeonia lactiflora Pall. Their structures were established on the basis of spectroscopic data.

Copacamphane, picrotoxane and cyclocopacamphane sesquiterpenes from Dendrobium nobile.

Dendronobilins K - N, four new sesquiterpenes with copacamphane-type (1), picrotoxane-type (2, 3) and cyclocopacamphane-type (4) skeletons, were isolated from the n-BuOH soluble fraction of the 60% ethanol extract of the stems of Dendrobium nobile. Their structures were established as 2beta,11,12-trihydroxycopacamphan-15-one (1), (2beta,3beta,4beta,5beta)-2,4,11,12-tetrahydroxypicrotoxan-3(15)-olactone (2), (2beta,3beta,5beta)-2,11,12,13-tetrahydroxypicrotoxan-3(15)-olactone (3), and (5beta,8beta)-cyclocopacamphane-5,8,12,15-tetrol (4) on the basis of spectroscopic analysis. Compounds 3 and 4 were inactive in both immunomodulatory and antioxidant bioassay in vitro.