Finding the bad actor: Challenges in identifying toxic constituents in botanical dietary supplements

Compounds isolation from Syzygium cumini leaf extract against the Vibrio species in shrimp through bioassay-guided fractionation

This study was conducted to isolate and identify the bioactive compounds from the ethanolic extract of Syzygium cumini leaf against Vibrio species through a bioassay-guided fractionation. The ethanol extract was exposed to silica gel chromatography followed by reversed phase HPLC to isolate the most effective fraction against V. parahaemolyticus. Using further UHPLC-orbitrap-ion trap mass spectrometry, five compounds were isolated with broad-spectrum potency against a range of Vibrio species viz. V. parahaemolyticus, V. alginolyticus, V. harveyi, V. vulnificus and V. anguillarum. The IC50 values for the compounds ranged from 8 to 48 µg/mL against the most sensitive species V. vulnificus and 58 to >400 µg/mL against V. alginolyticus. The results of the toxicity tests demonstrated that the compounds were not harmful for shrimp. The study's findings indicate that S. cumini leaf extract may contain bioactive molecules that are able to be substituted for antibiotics to treat vibriosis in shrimp farming.

Development of a peptide reactivity assay for screening botanicals and natural substances: Proof of concept studies

Consumer products containing botanicals or natural substances (BNS) are often preferred because there is a perception that 'natural' is safe. As with any product ingredient, a thorough safety assessment must be conducted, including a determination of skin sensitization potential. A modification of the Peroxidase Peptide Reactivity Assay (PPRA) was explored for screening BNS (B-PPRA) for their reactivity to a model cysteine peptide. The PPRA incorporates a horseradish peroxidase‑hydrogen peroxide (+HRP/P) oxidation system for the activation of potential pre- and pro-haptens. BNS test materials contained <2% botanical constituent in either glycerin/water or propylene glycol/water. Stock solutions prepared in acetonitrile were diluted to 8 working concentrations. Direct reactivity was determined in reaction mixtures containing peptide and deferoxamine in potassium phosphate buffer. Enzyme-mediated reactivity determinations were performed with addition of +HRP/P. Initial studies demonstrated that results were reproducible and impact of carrier low. To determine the sensitivity of the assay, experiments were conducted with chamomile extract spiked with three sensitizers. Peptide depletion was observed in the +HRP/P reaction mixtures with isoeugenol spikes as low as 0.05%. The B-PPRA shows promise as a screening method for skin sensitization potential and could become part of a framework for the skin sensitization safety assessment of BNS.

Chemical and biological assessments of environmental mixtures: A review of current trends, advances, and future perspectives

Considering the chemical complexity and toxicity data gaps of environmental mixtures, most studies evaluate the chemical risk individually. However, humans are usually exposed to a cocktail of chemicals in real life. Mixture health assessment remains to be a research area having significant knowledge gaps. Characterization of chemical composition and bioactivity/toxicity are the two critical aspects of mixture health assessments. This review seeks to introduce the recent progress and tools for the chemical and biological characterization of environmental mixtures. The state-of-the-art techniques include the sampling, extraction, rapid detection methods, and the in vitro, in vivo, and in silico approaches to generate the toxicity data of an environmental mixture. Application of these novel methods, or new approach methodologies (NAMs), has increased the throughput of generating chemical and toxicity data for mixtures and thus refined the mixture health assessment. Combined with computational methods, the chemical and biological information would shed light on identifying the bioactive/toxic components in an environmental mixture.

Chemometric-Guided Approaches for Profiling and Authenticating Botanical Materials

Botanical supplements with broad traditional and medicinal uses represent an area of growing importance for American health management; 25% of U.S. adults use dietary supplements daily and collectively spent over $9. 5 billion in 2019 in herbal and botanical supplements alone. To understand how natural products benefit human health and determine potential safety concerns, careful in vitro, in vivo, and clinical studies are required. However, botanicals are innately complex systems, with complicated compositions that defy many standard analytical approaches and fluctuate based upon a plethora of factors, including genetics, growth conditions, and harvesting/processing procedures. Robust studies rely upon accurate identification of the plant material, and botanicals' increasing economic and health importance demand reproducible sourcing, as well as assessment of contamination or adulteration. These quality control needs for botanical products remain a significant problem plaguing researchers in academia as well as the supplement industry, thus posing a risk to consumers and possibly rendering clinical data irreproducible and/or irrelevant. Chemometric approaches that analyze the small molecule composition of materials provide a reliable and high-throughput avenue for botanical authentication. This review emphasizes the need for consistent material and provides insight into the roles of various modern chemometric analyses in evaluating and authenticating botanicals, focusing on advanced methodologies, including targeted and untargeted metabolite analysis, as well as the role of multivariate statistical modeling and machine learning in phytochemical characterization. Furthermore, we will discuss how chemometric approaches can be integrated with orthogonal techniques to provide a more robust approach to authentication, and provide directions for future research.

Reduction of blood glucose by plant extracts and their use in the treatment of diabetes mellitus; discrepancies in effectiveness between animal and human studies

ETHNOPHARMACOLOGICAL RELEVANCE

The global problem of diabetes, together with the limited access of large numbers of patients to conventional antidiabetic medicines, continues to drive the search for new agents. Ancient Asian systems such as traditional Chinese medicine, Japanese Kampo medicine, and Indian Ayurvedic medicine, as well as African traditional medicine and many others have identified numerous plants reported anecdotally to treat diabetes; there are probably more than 800 such plants for which there is scientific evidence for their activity, mostly from studies using various models of diabetes in experimental animals.

AIM OF THE REVIEW

Rather than a comprehensive coverage of the literature, this article aims to identify discrepancies between findings in animal and human studies, and to highlight some of the problems in developing plant extract-based medicines that lower blood glucose in patients with diabetes, as well as to suggest potential ways forward.

METHODS

In addition to searching the 2018 PubMed literature using the terms 'extract AND blood glucose, a search of the whole literature was conducted using the terms 'plant extracts' AND 'blood glucose' AND 'diabetes' AND 'double blind' with 'clinical trials' as a filter. A third search using PubMed and Medline was undertaken for systematic reviews and meta-analyses investigating the effects of plant extracts on blood glucose/glycosylated haemoglobin in patients with relevant metabolic pathologies.

FINDINGS

Despite numerous animal studies demonstrating the effects of plant extracts on blood glucose, few randomised, double-blind, placebo-controlled trials have been conducted to confirm efficacy in treating humans with diabetes; there have been only a small number of systematic reviews with meta-analyses of clinical studies. Qualitative and quantitative discrepancies between animal and human clinical studies in some cases were marked; the factors contributing to this included variations in the products among different studies, the doses used, differences between animal models and the human disease, and the impact of concomitant therapy in patients, as well as differences in the duration of treatment, and the fact that treatment in animals may begin before or very soon after the induction of diabetes.

CONCLUSION

The potential afforded by natural products has not yet been realised in the context of treating diabetes mellitus. A systematic, coordinated, international effort is required to achieve the goal of providing anti-diabetic treatments derived from medicinal plants.

Phytochemicals against TNFα-Mediated Neuroinflammatory Diseases

Tumor necrosis factor-alpha (TNF-α) is a well-known pro-inflammatory cytokine responsible for the modulation of the immune system. TNF-α plays a critical role in almost every type of inflammatory disorder, including central nervous system (CNS) diseases. Although TNF-α is a well-studied component of inflammatory responses, its functioning in diverse cell types is still unclear. TNF-α functions through its two main receptors: tumor necrosis factor receptor 1 and 2 (TNFR1, TNFR2), also known as p55 and p75, respectively. Normally, the functions of soluble TNF-α-induced TNFR1 activation are reported to be pro-inflammatory and apoptotic. While TNF-α mediated TNFR2 activation has a dual role. Several synthetic drugs used as inhibitors of TNF-α for diverse inflammatory diseases possess serious adverse effects, which make patients and researchers turn their focus toward natural medicines, phytochemicals in particular. Phytochemicals targeting TNF-α can significantly improve disease conditions involving TNF-α with fewer side effects. Here, we reviewed known TNF-α inhibitors, as well as lately studied phytochemicals, with a role in inhibiting TNF-α itself, and TNF-α-mediated signaling in inflammatory diseases focusing mainly on CNS disorders.

Evaluating Sufficient Similarity of Botanical Dietary Supplements: Combining Chemical and In Vitro Biological Data

Botanical dietary supplements are complex mixtures with numerous potential sources of variation along the supply chain from raw plant material to the market. Approaches for determining sufficient similarity (ie, complex mixture read-across) may be required to extrapolate efficacy or safety data from a tested sample to other products containing the botanical ingredient(s) of interest. In this work, screening-level approaches for generating both chemical and biological-response profiles were used to evaluate the similarity of black cohosh (Actaea racemosa) and Echinacea purpurea samples to well-characterized National Toxicology Program (NTP) test articles. Data from nontargeted chemical analyses and gene expression of toxicologically important hepatic receptor pathways (aryl hydrocarbon receptor [AhR], constitutive androstane receptor [CAR], pregnane X receptor [PXR], farnesoid X receptor [FXR], and peroxisome proliferator-activated receptor alpha [PPARα]) in primary human hepatocyte cultures were used to determine similarity through hierarchical clustering. Although there were differences in chemical profiles across black cohosh samples, these differences were not reflected in the biological-response profiles. These findings highlight the complexity of biological-response dynamics that may not be reflected in chemical composition profiles. Thus, biological-response data could be used as the primary basis for determining similarity among black cohosh samples. Samples of E. purpurea displayed better correlation in similarity across chemical and biological-response measures. The general approaches described herein can be applied to complex mixtures with unidentified active constituents to determine when data from a tested mixture (eg, NTP test article) can be used for hazard identification of sufficiently similar mixtures, with the knowledge of toxicological targets informing assay selection when possible.

Cyberecoethnopharmacolomics

ETHNOPHARMACOLOGICAL RELEVANCE

Development of a new term which describes the contemporary, composite, constituent sciences of ethnopharmacology.

AIM OF THE STUDY

To discuss the polysyllabic term cyberecoethnopharmacolomics in the context of the future of ethnopharmacology in global health care.

MATERIALS AND METHODS

Literature background and assessment from the prior literature, diverse databases, and personal discussions.

RESULTS

The profiles and literature background with contemporary and future thoughts regarding the concepts and practices of cyber-, eco-, ethno-, pharmacol-, and -omics, and their impact in ethnopharmacology for the future are presented in the context of integrated health care systems.

CONCLUSIONS

Ethnopharmacology has a major role to play in global health care if the relevant sciences and cutting-edge technologies can coalesce synergistically as a responsive, evidence-based health care practice.

Using Tox21 High-Throughput Screening Assays for the Evaluation of Botanical and Dietary Supplements

Introduction: Recent nationwide surveys found that natural products, including botanical dietary supplements, are used by ∼18% of adults. In many cases, there is a paucity of toxicological data available for these substances to allow for confident evaluations of product safety. The National Toxicology Program (NTP) has received numerous nominations from the public and federal agencies to study the toxicological effects of botanical dietary supplements. The NTP sought to evaluate the utility of in vitro quantitative high-throughput screening (qHTS) assays for toxicological assessment of botanical and dietary supplements.

Materials and Methods: In brief, concentration–response assessments of 90 test substances, including 13 distinct botanical species, and individual purported active constituents were evaluated using a subset of the Tox21 qHTS testing panel. The screen included 20 different endpoints that covered a broad range of biologically relevant signaling pathways to detect test article effects upon endocrine activity, nuclear receptor signaling, stress response signaling, genotoxicity, and cell death signaling.

Results and Discussion: Botanical dietary supplement extracts induced measurable and diverse activity. Elevated biological activity profiles were observed following treatments with individual chemical constituents relative to their associated botanical extract. The overall distribution of activity was comparable to activities exhibited by compounds present in the Tox21 10K chemical library.

Conclusion: Botanical supplements did not exhibit minimal or idiosyncratic activities that would preclude the use of qHTS platforms as a feasible method to screen this class of compounds. However, there are still many considerations and further development required when attempting to use in vitro qHTS methods to characterize the safety profile of botanical/dietary supplements.