Developing a Screening Strategy to Identify Hepatotoxicity and Drug Interaction Potential of Botanicals.

Botanical supplements, herbal remedies, and plant-derived products are used globally. However, botanical dietary supplements are rarely subjected to robust safety testing unless there are adverse reports in post-market surveillance. Botanicals are complex and difficult to assess using current frameworks designed for single constituent substances (e.g. small molecules or discrete chemicals), making safety assessments costly and time-consuming. The liver is a primary organ of concern for potential botanical-induced hepatotoxicity and botanical-drug interactions as it plays a crucial role in xenobiotic metabolism. The NIH-funded Drug Induced Liver Injury Network noted that the number of botanical-induced liver injuries in 2017 nearly tripled from those observed in 2004-2005. New approach methodologies (NAMs) can aid in the rapid and cost-effective assessment of botanical supplements for potential hepatotoxicity. The Hepatotoxicity Working Group within the Botanical Safety Consortium is working to develop a screening strategy that can help reliably identify potential hepatotoxic botanicals and inform mechanisms of toxicity. This manuscript outlines the Hepatotoxicity Working Group's strategy and describes the assays selected and the rationale for the selection of botanicals used in case studies. The selected NAMs evaluated as a part of this effort are intended to be incorporated into a larger battery of assays to evaluate multiple endpoints related to botanical safety. This work will contribute to a botanical safety toolkit, providing researchers with tools to better understand hepatotoxicity associated with botanicals, prioritize and plan future testing as needed, and gain a deeper insight into the botanicals being tested.

A comparative metabolomics analysis of Açaí (Euterpe oleracea Mart.) fruit, food powder, and botanical dietary supplement extracts.

INTRODUCTION: Euterpe oleracea Mart. (açaí) is a botanical of interest to many who seek functional foods that provide antioxidant and anti-inflammatory properties. Cancer patients are increasingly taking botanical dietary supplements containing açaí to complement their conventional therapeutics, which may lead to serious adverse events. Before testing our açaí extracts in vitro for botanical-drug interactions, the goal is to chemically characterize our extracts for compounds whose biological activity in açaí is unknown. OBJECTIVE: The objective of this work was to develop a chemical fingerprinting method for untargeted characterization of açaí samples from a variety of sources, including food products and botanical dietary supplement capsules, made with multiple extraction solvents. METHODS: An optimized LC-MS method was generated for in-depth untargeted fingerprinting of chemical constituents in açaí extracts. Statistical analysis models were used to describe relationships between the açaí extracts based on molecular features found in both positive and negative mode ESI. RESULTS: In an attempt to elucidate the differences in metabolites among açaí extracts from different cultivars, we identified or tentatively identified 173 metabolites from the 16 extracts made from 6 different sources. Of these compounds, there are 138 reported in açaí for the first time. Statistical models showed similar yet distinct differences between the extracts tested based on the polarity of compounds present and the origin of the source material. CONCLUSION: A high-resolution mass spectrometry method was generated that allowed us to greatly characterize 16 complex extracts made from different sources of açaí with different extraction solvent polarities.

Standardization of açaí extracts for in-vitro assays based on anthocyanin quantitation.

Euterpe oleracea Mart., commonly known as açaí, is a fruit that grows on a palm tree native to the Amazon region. Quantitation of bioactive constituents is a crucial preliminary step before utilizing extracts for biological assays so they may be normalized and administered according to a specific constituent concentration. Açaí has four main anthocyanin analytes: cyanidin 3-glucoside, cyanidin 3-sambubioside, cyanidin 3-rutinoside, and peonidin 3-rutinoside. This is the first comparison of açaí anthocyanin profiles between fresh fruits, processed powders, and botanical dietary supplement capsules. The materials examined shared a similar anthocyanin profile, with cyanidin 3-rutinoside being the most abundant (0.380 ± 0.006 - 15.1 ± 0.01 mg/g), followed by cyanidin 3-glucoside (0.0988 ± 0.0031 - 8.95 ± 0.01 mg/g). Among the botanical dietary supplement capsules, the two formulations varied greatly in anthocyanin concentration despite both being aqueous extracts (0.650 ± 0.011 - 0.924 ± 0.010 mg/g versus 1.23 ± 0.01 - 1.27 ± 0.02 mg/g). Previous LC-MS methods range from 35-120 min per injection, while we report a 10 min quantitative method for analysis of anthocyanins in various açaí materials that is fast, reproducible, and accurate. The method produced is useful to assure the quality, efficacy and safety of food and dietary supplement materials containing açaí.

Investigation of the chemical composition of antibacterial Psidium guajava extract and partitions against foodborne pathogens.

P. guajava was partitioned into aqueous and ethyl acetate fractions and studied for its antibacterial chemical constituents. The minimum inhibitory concentrations of the aqueous and ethyl acetate partitions against Escherichia coli, Salmonella Typhimurium, and Staphylococcus aureus were found to be 0.75, 0.75, 0.15, 0.5, 0.5, and 0.125%, respectively. Using LC-MS-based chemical fingerprinting, auto MS/MS fragmentation and bioactive molecular networking, 18 compounds of interest were detected. The top 10 bioactive compounds and eight additional non-bioactive compounds known to be found in P. guajava are highlighted. We report five compounds to be identified in P. guajava for the first time. Studies have indicated P. guajava to be a plant source of antibacterial compounds that could be useful in the food industry to prevent foodborne illnesses outbreaks, reduce food spoilage, and satisfy consumer demands for less synthetic chemical usage in the food industry.

Bioactive Natural Products Identification Using Automation of Molecular Networking Software.

Secondary metabolites from natural sources are promising starting points for discovering and developing drug prototypes and new drugs, as many current treatments for numerous diseases are directly or indirectly related to such compounds. Recent advances in bioinformatics tools and molecular networking methods have made it possible to identify novel bioactive compounds. In this study, a workflow combining network-based methods for identifying bioactive compounds found in natural products was streamlined by innovating an automated bioinformatics software. The workflow relies on Global Natural Product Social Molecular Networking (GNPS), a web-based mass spectrometry ecosystem that aims to be an open-access knowledge base for community-wide organization and sharing of raw, processed, or annotated fragmentation mass spectrometry data. By combining computational tools including MZmine2, GNPS, and Cytoscape, the integrated dashboard quickly creates bioactive molecular networks with minimal user intervention and reduces the processing time of the original workflow by over 80%. This newly automated workflow quickens the process of discovering bioactive compounds from natural products. This study uses extracts from Psidium guajava leaves to demonstrate the application of our automated software.

United States Pharmacopeia comprehensive safety review of Styphnolobium japonicum flower and flower bud.

The dried flower and flower bud of Styphnolobium japonicum (L.) Schott (Japanese Sophora flower and Japanese Sophora flower bud, respectively) have long been used as herbal medicines in Asia. Today, they are marketed as dietary supplements in the United States for their anti-oxidative properties and as a source of flavonoids, including rutin and quercetin. This review focused on the safety of S. japonicum flower and flower bud as dietary supplement ingredients. No serious adverse events or toxicity were reported in the clinical or experimental animal studies we reviewed. Although some studies indicated that rutin or quercetin may have potential for drug interactions, none were identified for S. japonicum flower or flower bud. S. japonicum flower and flower bud are not known to have been associated with serious health risks when appropriately consumed in dietary supplements and have been admitted to the U.S. Pharmacopeial Convention monograph development process. However, pregnant and breastfeeding women should seek the advice of a healthcare professional because no data are available on their use by these special populations.

Rational and Safe Use of the Top Two Botanical Dietary Supplements to Enhance the Immune System.

The recent COVID-19 pandemic has sparked great interest in strengthening the immune system, especially by the consumption of widely available natural dietary supplements. Because of this popularity, it was suggested that the sales of these products would grow significantly in the year 2021, especially for those who are unable or unwilling to receive COVID-19 vaccines. Among the many botanicals, Sambucus nigra L. (Elderberry) and Echinacea purpurea (L.) Moench (Echinacea) have especially shown great popularity. Various in vivo and in vitro tests of S. nigra and E. purpurea extracts and constituents have confirmed the botanicals' influence on proinflammatory cytokines, viral infections, and flu symptoms, proving their immunomodulatory and antiviral effects. Although there have been promising results with S. nigra and E. purpurea containing supplements, thorough monitoring of the sanitary production, demand, and related side effects after consumption is required. Further research and development of the supplements in accordance with the pandemic are also advised.

Combination of HRLC-MS with MPP and GNPS data analysis to identify major constituents of MtSK inhibitory Alpinia galanga extract.

Alpinia galanga (L.) Willd. (Zingiberaceae), or galangal, has been previously reported as active against Mycobacterium tuberculosis (TB) in vitro. The present study assessed a novel antitubercular mechanism of of galangal through M. tuberculosis shikimate kinase (MtSK) inhibitory assays. Sequential extractions of nonpolar solvents hexane and dichloromethane (DCM) were performed on galangal and screened in MtSK inhibitory assays to identify potential activity. Samples were then subjected to high resolution (HR) LC-MS chemical fingerprinting and analysis. Additionally, a novel approach was undertaken for galangal using methods such as mass professional profiler (MPP) and global natural products social (GNPS) molecular networking for structure elucidation.[Formula: see text].

Natural Products with Potential for Nonhormonal Male Contraception.

Despite increased access to contraception over the last 60 years, unplanned pregnancies continue to contribute to economic disparities and overpopulation. Additionally, the burden of family planning falls primarily on women, as a reliable pharmaceutical male contraceptive has yet to be developed. The objective of this literature-based systematic review was to identify compounds for future study from natural sources with potential nonhormonal male contraceptive activity. After the exclusion of extracts and compounds with known hormonal mechanisms, 26 unique compounds were identified from natural species. The plant source, compound class, structure, target, mechanism of action, safety/toxicity profile, and in vitro, in vivo, and human studies for each compound were evaluated and discussed. ß-Caryophyllene, embelin, oleanolic acid, triptonide, and N-butyldeoxynojirimycin (NB-DNJ) were selected as the five most promising compounds for future study using prespecified criteria such as number of studies, efficacy and safety profile, reversibility, and previous use in humans for any indication. In order to move forward with development of a male contraceptive from a natural source, additional studies are needed to determine the predicted safety and efficacy for in vivo and human clinical trials.

Safety of Cranberry: Evaluation of Evidence of Kidney Stone Formation and Botanical Drug-Interactions.

Cranberry is a popular ingredient in dietary supplements in the U. S. and is commonly used for preventing urinary tract infections. Because of its popularity in dietary supplements, the U. S. Pharmacopeial Convention has developed quality standards for cranberry ingredients. The purpose of this review was to determine if there are safety issues that should preclude the admission of cranberry ingredients from the development of U. S. Pharmacopeial Convention quality standards. Based on the totality of the data, the U. S. Pharmacopeial Convention concluded that cranberry ingredients are not known to be associated with serious risks to human health when consumed properly in dietary supplements and therefore were admitted for standard development. Although published clinical and animal data indicated that cranberry is not associated with serious adverse effects, interactions with warfarin and kidney stone formation were identified as potential risks. Studies have reported contradictory data regarding the role of cranberry in kidney stone formation, with some reports suggesting cranberry is associated with a reduced risk of kidney stones. Interactions with warfarin were not associated with moderate intakes of cranberry juice (240 - 480 mL). Some reports suggested that the potential for warfarin interactions requires excessive intakes of cranberry juice (1 - 2 L/day) or cranberry extracts (3000 mg/day). Cases of warfarin interactions with cranberry have mostly involved patients with serious illnesses and/or individuals taking concomitant medications. Based on these findings, the U. S. Pharmacopeial Convention concluded that the use of cautionary labeling statements regarding interactions with warfarin or kidney stone formation is not necessary in the development of quality standards for cranberry ingredients.

Reproducible molecular networking of untargeted mass spectrometry data using GNPS.

Global Natural Product Social Molecular Networking (GNPS) is an interactive online small molecule-focused tandem mass spectrometry (MS2) data curation and analysis infrastructure. It is intended to provide as much chemical insight as possible into an untargeted MS2 dataset and to connect this chemical insight to the user's underlying biological questions. This can be performed within one liquid chromatography (LC)-MS2 experiment or at the repository scale. GNPS-MassIVE is a public data repository for untargeted MS2 data with sample information (metadata) and annotated MS2 spectra. These publicly accessible data can be annotated and updated with the GNPS infrastructure keeping a continuous record of all changes. This knowledge is disseminated across all public data; it is a living dataset. Molecular networking-one of the main analysis tools used within the GNPS platform-creates a structured data table that reflects the molecular diversity captured in tandem mass spectrometry experiments by computing the relationships of the MS2 spectra as spectral similarity. This protocol provides step-by-step instructions for creating reproducible, high-quality molecular networks. For training purposes, the reader is led through a 90- to 120-min procedure that starts by recalling an example public dataset and its sample information and proceeds to creating and interpreting a molecular network. Each data analysis job can be shared or cloned to disseminate the knowledge gained, thus propagating information that can lead to the discovery of molecules, metabolic pathways, and ecosystem/community interactions.

Safety of Guarana Seed as a Dietary Ingredient: A Review.

The seeds of the guarana plant (Paullinia cupana Kunth, family Sapindaceae) are well-known to many cultures as a stimulant, aphrodisiac, and astringent. Its rhizome was traditionally boiled into a tea by Amazonian cultures. Today, guarana seeds are ground to a fine powder and sold as powder, tablets, and capsules. This review focuses on the traditional uses, phytochemistry, and biological activities of the guarana seed to evaluate its safety as a dietary ingredient. A comprehensive review of published literature was conducted to identify articles that focused on the phytochemistry, pharmacology, and safety of guarana. On the basis of this review, guarana is not currently known to be associated causally with any serious health risks when consumed properly. Overall, guarana is generally recognized as safe as a dietary ingredient marketed for its flavor and caffeine content. If guidelines for caffeine intake are respected, guarana consumption is not likely to be associated with any serious health risks.

Biochemometrics and Required Tools in Botanical Natural Products Research: A Review.

This review serves to highlight the role of chemometrics and biochemometrics in recent literature as well as including a perspective on the current state of the field, as well as the future needs and possible directions. Specifically examining the analytical methods and statistical tools that are available to chemists, current applications of QTOF-MS, Orbitrap-MS, LC with PDA/UV detectors, NMR, and IMS coupled MS are detailed. Of specific interest, these techniques can be applied to botanical dietary supplement quality, efficacy, and safety. Application in natural products drug discovery, industrial quality control, experimental design, and more are also discussed.

Screening for CYP3A4 inhibition and induction coupled to parallel artificial membrane permeability assay (PAMPA) for prediction of botanical-drug interactions: The case of açaí and maca.

BACKGROUND: The consumption of botanical dietary supplements (BDS) is a common practice among the US population. However, the potential for botanical-drug interactions exists, and their mechanisms have not been thoroughly studied. CYP3A4 is an important enzyme that contributes to the metabolism of about 60% of clinically used drugs. PURPOSE: To investigate the potential for botanical-drug interactions of Lepidium meyenii Walpers (maca) root and Euterpe oleracea Mart. (açaí) berries, two commonly used BDS, when co-administered with CYP3A4-metabolized drugs. METHODS: In an attempt to decrease the general discrepancy between in vivo and in vitro studies, the absorption profiles, particularly for passive diffusion, of plant extracts were investigated. Specifically, the parallel artificial membrane permeability assay (PAMPA) model was utilized to simulate intestinal filtration of passively diffused constituents of açaí and maca extracts. These were subsequently screened for in vitro liver CYP3A4 inhibition and induction. In the inhibition assay, midazolam was used as the probe substrate on genotyped human liver microsomes (CYP3A5 null), and the production of its 1'-substituted metabolite when co-cultured with extract treatments was monitored. In the induction assay, extract treatments were applied to human primary hepatocytes, and quantitative PCR analysis was performed to determine CYP3A4 mRNA expression. RESULTS: Passively diffused constituents of the methanol açaí extract (IC50 of 28.03 µg/µl) demonstrated the highest inhibition potential, and, at 1.5 µg/µl, induced significant changes in CYP3A4 gene expression. The composition of this extract was further investigated using the chemometric tool Mass Profiler Professional (MPP) on liquid chromatography-mass spectroscopy (LC-MS) data. Subsequently, five compounds of interest characterized by high abundance or high permeability were extracted for further study. This included efforts in effective passive permeability determination and structural elucidation by tandem mass spectrometry (MS/MS). CONCLUSION: The passively absorbable portion of a methanol açaí extract exhibited inhibition and induction effects on CYP3A4 suggesting the potential to produce botanical-drug interactions.

Adverse event reporting patterns of concomitant botanical dietary supplements with CYP3A4 interactive & CYP3A4 non-interactive anticancer drugs in the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS).

BACKGROUND: To examine the adverse event (AE) reporting patterns for concomitant Botanical Dietary Supplements (BDS) and anticancer drugs. RESEARCH DESIGN AND METHODS: Using the 2004-2015 U.S. Food and Drug Administration Adverse Event Reporting System (FAERS) database, AEs involving commonly used BDS and anticancer drugs (categorized into CYP3A4 interactive and CYP3A4 non-interactive) were examined. Disproportionality analyses using reporting odds ratios (RORs) assessed the relative reporting rates of 1) serious AEs (i.e., mortality and morbidity) with concomitant use of BDS (overall and by type) and anticancer drugs compared to anticancer drugs only; and 2) AEs by specific System Organ Classes (SOCs). RESULTS: A total of 3,264 AEs were reported involving concomitant BDS and CYP3A4 interactives, and 3,885 involving concomitant BDS and non-interactive anticancer drugs. ROR of serious AEs with concomitant all BDS and anticancer drugs compared to anticancer drugs alone showed a potential protective signal (ROR = 0.65, 95% CI = 0.62,0.68), but ROR for açaí and non-interactive anticancer drugs indicated potential risk (ROR = 1.70, 95% CI = 1.01,2.86). Heterogeneity of reporting patterns of AEs related to certain SOCs was observed for use of BDS along with anticancer drugs. CONCLUSION: This study identified potential protective and risk signals for AEs with concomitant use of BDS and anticancer drugs.

Slow-Binding Inhibition of Mycobacterium tuberculosis Shikimate Kinase by Manzamine Alkaloids.

Tuberculosis represents a significant public health crisis. There is an urgent need for novel molecular scaffolds against this pathogen. We screened a small library of marine-derived compounds against shikimate kinase from Mycobacterium tuberculosis ( MtSK), a promising target for antitubercular drug development. Six manzamines previously shown to be active against M. tuberculosis were characterized as MtSK inhibitors: manzamine A (1), 8-hydroxymanzamine A (2), manzamine E (3), manzamine F (4), 6-deoxymanzamine X (5), and 6-cyclohexamidomanzamine A (6). All six showed mixed noncompetitive inhibition of MtSK. The lowest KI values were obtained for 6 across all MtSK-substrate complexes. Time-dependent analyses revealed two-step, slow-binding inhibition. The behavior of 1 was typical; initial formation of an enzyme-inhibitor complex (EI) obeyed an apparent KI of ∼30 µM with forward ( k5) and reverse ( k6) rate constants for isomerization to an EI* complex of 0.18 and 0.08 min-1, respectively. In contrast, 6 showed a lower KI for the initial encounter complex (∼1.5 µM), substantially faster isomerization to EI* ( k5 = 0.91 min-1), and slower back conversion of EI* to EI ( k6 = 0.04 min-1). Thus, the overall inhibition constants, KI*, for 1 and 6 were 10 and 0.06 µM, respectively. These findings were consistent with docking predictions of a favorable binding mode and a second, less tightly bound pose for 6 at MtSK. Our results suggest that manzamines, in particular 6, constitute a new scaffold from which drug candidates with novel mechanisms of action could be designed for the treatment of tuberculosis by targeting MtSK.

Mechanism of irreversible inhibition of Mycobacterium tuberculosis shikimate kinase by ilimaquinone.

Ilimaquinone (IQ), a marine sponge metabolite, has been considered as a potential therapeutic agent for various diseases due to its broad range of biological activities. We show that IQ irreversibly inactivates Mycobacterium tuberculosis shikimate kinase (MtSK) through covalent modification of the protein. Inactivation occurred with an apparent second-order rate constant of about 60 M-1 s-1. Following reaction with IQ, LC-MS analyses of intact MtSK revealed covalent modification of MtSK by IQ, with the concomitant loss of a methoxy group, suggesting a Michael-addition mechanism. Evaluation of tryptic fragments of IQ-derivatized MtSK by MS/MS demonstrated that Ser and Thr residues were most frequently modified with lesser involvement of Lys and Tyr. In or near the MtSK active site, three residues of the P-loop (K15, S16, and T17) as well as S77, T111, and S44 showed evidence of IQ-dependent derivatization. Accordingly, inclusion of ATP in IQ reactions with MtSK partially protected the enzyme from inactivation and limited IQ-based derivatization of K15 and S16. Additionally, molecular docking models for MtSK-IQ were generated for IQ-derivatized S77 and T111. In the latter, ATP was observed to sterically clash with the IQ moiety. Out of three other enzymes evaluated, lactate dehydrogenase was derivatized and inactivated by IQ, but pyruvate kinase and catalase-peroxidase (KatG) were unaffected. Together, these data suggest that IQ is promiscuous (though not entirely indiscriminant) in its reactivity. As such, the potential of IQ as a lead in the development of antitubercular agents directed against MtSK or other targets is questionable.

A Review of the Toxicity of Compounds Found in Herbal Dietary Supplements.

Use of herbal dietary supplements by the public is common and has been happening for centuries. In the United States, the Food and Drug Administration has a limited scope of regulation over marketed herbal dietary supplements, which may contain toxic botanical compounds that pose a public health risk. While the Food and Drug Administration has made efforts to prohibit the sale of unsafe herbal dietary supplements, numerous reports have proliferated of adverse events due to these supplements. This literature review investigates bioactive plant compounds commonly used in herbal dietary supplements and their relative toxicities. Using primarily the National Library of Medicine journal database and SciFinder for current reports, 47 toxic compounds in 55 species from 46 plant families were found to demonstrate harmful effects due to hepatic, cardiovascular, central nervous system, and digestive system toxicity. This review further contributes a novel and comprehensive view of toxicity across the botanical dietary market, and investigates the toxicity of the top ten botanical dietary supplements purchased in the United States of America to gauge the exposure risk of toxicity to the public. The criteria of measuring toxicity in this review (plant compound, family, quantity, and toxicity effects) across the entire market in the United States, with special attention to those supplements whose exposure to the consumer is maximal, provides a unique contribution to the investigation of botanical supplements.

Therapeutic Perspectives on Chia Seed and Its Oil: A Review.

The attraction of novel foods proceeds alongside epidemic cardiovascular disease, diabetes, obesity, and related risk factors. Dieticians have identified chia (Salvia hispanica) as a product with a catalog of potential health benefits relating to these detriments. Chia is currently consumed not only as seeds, but also as oil, which brings about similar effects. Chia seeds and chia seed oil are used mainly as a food commodity and the oil is also used popularly as a dietary ingredient used in various dietary supplements available in the U. S. market. Chia seed is rich in α-linolenic acid, the biological precursor to eicosapentaenoic acid, a polyunsaturated fatty acid, and docosahexaenoic acid. Because the body cannot synthesize α-linolenic acid, chia has a newfound and instrumental role in diet. However, the inconclusive nature of the scientific community's understanding of its safety warrants further research and appropriate testing. The focus of this work is to summarize dietary health benefits of S. hispanica seed and oil to acknowledge concerns of adverse events from its ingestion, to assess current research in the field, and to highlight the importance of quality compendial standards to support safe use. To achieve this end, a large-scale literature search was partaken on the two well-known databases, PubMed and SciFinder. Hundreds of articles detailing such benefits as decreased blood glucose, decreased waist circumference and weight in overweight adults, and improvements in pruritic skin and endurance in distance runners have been recorded. These benefits must be considered within the appropriate circumstances.

A multifaceted approach to identify non-specific enzyme inhibition: Application to Mycobacterium tuberculosis shikimate kinase.

Single dose high-throughput screening (HTS) followed by dose-response evaluations is a common strategy for the identification of initial hits for further development. Early identification and exclusion of false positives is a cost-saving and essential step in early drug discovery. One of the mechanisms of false positive compounds is the formation of aggregates in assays. This study evaluates the mechanism(s) of inhibition of a set of 14 compounds identified previously as actives in Mycobacterium tuberculosis (Mt) cell culture screening and in vitro actives in Mt shikimate kinase (MtSK) assay. Aggregation of hit compounds was characterized using multiple experimental methods, LC-MS, 1HNMR, dynamic light scattering (DLS), transmission electron microscopy (TEM), and visual inspection after centrifugation for orthogonal confirmation. Our results suggest that the investigated compounds containing oxadiazole-amide and aminobenzothiazole moieties are false positive hits and non-specific inhibitors of MtSK through aggregate formation.