National Center for Complementary and Integrative Health Perspectives on Clinical Research Involving Natural Products

Red Bull Energy Drink Impact on Salivary Glands in Wistar Rats: Can Blueberry Extract Reverse the Damage?

Energy drink (ED) consumption has become increasingly popular. Due to a lack of evidence, it was crucial to assess the effects of Red Bull (RB) consumption on the rat submandibular salivary gland and the potential therapeutic impact of blueberry (BB). Thirty rats were randomly assigned to five groups. Group 1 (Control) received distilled water. Group 2 (RB) received RB (10 mL/100 g/day) for 8 weeks. Group 3 (BB) rats were administered BB (500 mg/day for 8 weeks). Group 4 (RB + BB (L)) received RB for 8 weeks, and from the 5th week, were concurrently given BB (250 mg/day) for 4 weeks. Group 5 (RB + BB (H)) received RB for 8 weeks, and from the 5th week, were concurrently given BB (500 mg/day) for 4 weeks. At the end of the experiment, blood samples were collected, the animals were euthanized, and their submandibular salivary glands were harvested. Oxidative stress markers (MDA, GPx, CAT, and SOD) were assessed in both serum and tissue. Inflammatory markers (TNF-α, IL-6, and IL-10) were quantified in tissue. Submandibular gland specimens were prepared for light microscopy, and immunohistochemical staining was performed using anti-α-SMA. RB consumption resulted in a significant increase in MDA, TNF-α, IL-6, and IL-10, while GPx, CAT, and SOD levels decreased significantly. Degenerative changes in the gland's structure were observed in the RB group. A significant increase in α-SMA immunoreaction was detected in myoepithelial cells. Administration of BB, particularly at a high dose, ameliorated the aforementioned findings. In conclusion, blueberry administration exhibited therapeutic effects due to its antioxidative and anti-inflammatory properties.

The Evolution of Science and Regulation of Dietary Supplements: Past, Present, and Future

Dietary supplement use in the United States is widespread and increasing, especially among certain population groups, such as older Americans. The science surrounding dietary supplements has evolved substantially over the last few decades since their formal regulation in 1994. Much has been learned about the mechanisms of action of many dietary supplement ingredients, but the evidence on their health effects is still building. As is true of much nutrition research, there are many studies that point to health effects, but not all are at the level of scientific evidence (e.g., randomized controlled interventions), rigor, or quality needed for definitive statements of efficacy regarding clinical end points. New technologies and approaches are being applied to the science of dietary supplements, including nutrigenomics and microbiome analysis, data science, artificial intelligence (AI), and machine learning-all of which can elevate the science behind dietary supplements. Products can contain an array of bioactive compounds derived from foods as well as from medicinal plants, which creates enormous challenges in data collection and management. Clinical applications, particularly those aimed at providing personalized nutrition options for patients, have become more sophisticated as dietary supplements are incorporated increasingly into clinical practice and self-care. The goals of this article are to provide historical context for the regulation and science of dietary supplements, identify research resources, and suggest some future directions for science in this field.

Natural Products Inhibition of Cytochrome P450 2B6 Activity and Methadone Metabolism

Methadone is cleared predominately by hepatic cytochrome P450 (CYP) 2B6-catalyzed metabolism to inactive metabolites. CYP2B6 also catalyzes the metabolism of several other drugs. Methadone and CYP2B6 are susceptible to pharmacokinetic drug-drug interactions. Use of natural products such as herbals and other botanicals is substantial and growing, and concomitant use of prescription medicines and non-prescription herbals is common and may result in interactions, often precipitated by CYP inhibition. Little is known about herbal product effects on CYP2B6 activity, and CYP2B6-catalyzed methadone metabolism. We screened a family of natural product compounds used in traditional medicines, herbal teas, and synthetic analogs of compounds found in plants, including kavalactones, flavokavains, chalcones and gambogic acid, for inhibition of expressed CYP2B6 activity and specifically inhibition of CYP2B6-mediated methadone metabolism. An initial screen evaluated inhibition of CYP2B6-catalyzed 7-ethoxy-4-(trifluoromethyl) coumarin O-deethylation. Hits were further evaluated for inhibition of racemic methadone metabolism, including mechanism of inhibition and kinetic constants. In order of decreasing potency, the most effective inhibitors of methadone metabolism were dihydromethysticin (competitive, K i 0.074 µM), gambogic acid (noncompetitive, K i 6 µM), and 2,2'-dihydroxychalcone (noncompetitive, K i 16 µM). Molecular modeling of CYP2B6-methadone and inhibitor binding showed substrate and inhibitor binding position and orientation and their interactions with CYP2B6 residues. These results show that CYP2B6 and CYP2B6-catalyzed methadone metabolism are inhibited by certain natural products, at concentrations which may be clinically relevant. SIGNIFICANCE STATEMENT: This investigation identified several natural product constituents which inhibit in vitro human recombinant CYP2B6 and CYP2B6-catalyzed N-demethylation of the opioid methadone. The most potent inhibitors (K i) were dihydromethysticin (0.074 µM), gambogic acid (6 µM) and 2,2'-dihydroxychalcone (16 µM). Molecular modeling of ligand interactions with CYP2B6 found that dihydromethysticin and 2,2'-dihydroxychalcone bound at the active site, while gambogic acid interacted with an allosteric site on the CYP2B6 surface. Natural product constituents may inhibit CYP2B6 and methadone metabolism at clinically relevant concentrations.

Investigation of usage, attitudes toward complementary and alternative medicine among cancer patients in Turkey during the COVID-19 pandemic1

BACKGROUND

Complementary and alternative medicines (CAM) are being uses more often with cancer patients.

OBJECTIVE

This study aimed to investigate attitudes, use and influencing factors of CAM among cancer patients during the COVID-19 pandemic.

METHODS

This descriptive, cross-sectional study was conducted on 407 cancer patients in Turkey. The study was conducted during July-September 2021 using a Questionnaire that included a Complementary, Alternative and Conventional Medicine Attitude Scale (CACMAS). Pearson's Chi-Squared Test, Mann-Whitney U, Kruskal Wallis, and logistic regression were all utilized.

RESULTS

The findings revealed that 76.2% of the participants stated that they used CAM methods while undergoing cancer treatment, and 65.2% of those who did so kept from sharing this information to medical professionals. Phytotherapy was the most common CAM method used by patients. The use of CAM was found to be significantly higher among those who were 55-64 years of age, married, secondary school graduates, non-smokers, CAM users before their cancer diagnosis, and who had a family history of cancer (p < 0.05). The participants' average CACMAS scores were 112.20±16.53. Among those who used CAM during treatment, non-smoking, overweight-obese participants had higher CACMAS scores (p < 0.05).

CONCLUSION

Due to the high prevalence of CAM usage among cancer patients and possible interaction effects with chemotherapy medications, it is important for healthcare professionals to assess and educate cancer patients regarding CAM use. Additional research is needed to determine potential interactions, as well as pros and cons of CAM use during cancer treatment.

Perspective: Council for Responsible Nutrition Science in Session. Optimizing Health with Nutrition-Opportunities, Gaps, and the Future

Achieving optimal health is an aspirational goal for the population, yet the definition of health remains unclear. The role of nutrition in health has evolved beyond correcting malnutrition and specific deficiencies and has begun to focus more on achieving and maintaining 'optimal' health through nutrition. As such, the Council for Responsible Nutrition held its October 2022 Science in Session conference to advance this concept. Here, we summarize and discuss the findings of their Optimizing Health through Nutrition - Opportunities and Challenges workshop, including several gaps that need to be addressed to advance progress in the field. Defining and evaluating various indices of optimal health will require overcoming these key gaps. For example, there is a strong need to develop better biomarkers of nutrient status, including more accurate markers of food intake, as well as biomarkers of optimal health that account for maintaining resilience-the ability to recover from or respond to stressors without loss to physical and cognitive performance. In addition, there is a need to identify factors that drive individualized responses to nutrition, including genotype, metabotypes, and the gut microbiome, and to realize the opportunity of precision nutrition for optimal health. This review outlines hallmarks of resilience, provides current examples of nutritional factors to optimize cognitive and performance resilience, and gives an overview of various genetic, metabolic, and microbiome determinants of individualized responses.

Developing a Rational, Optimized Product of Centella asiatica for Examination in Clinical Trials: Real World Challenges

Botanical products are frequently sold as dietary supplements and their use by the public is increasing in popularity. However, scientific evaluation of their medicinal benefits presents unique challenges due to their chemical complexity, inherent variability, and the involvement of multiple active components and biological targets. Translation away from preclinical models, and developing an optimized, reproducible botanical product for use in clinical trials, presents particular challenges for phytotherapeutic agents compared to single chemical entities. Common deficiencies noted in clinical trials of botanical products include limited characterization of the product tested, inadequate placebo control, and lack of rationale for the type of product tested, dose used, outcome measures or even the study population. Our group has focused on the botanical Centella asiatica due to its reputation for enhancing cognition in Eastern traditional medicine systems. Our preclinical studies on a Centella asiatica water extract (CAW) and its bioactive components strongly support its potential as a phytotherapeutic agent for cognitive decline in aging and Alzheimer's disease through influences on antioxidant response, mitochondrial activity, and synaptic density. Here we describe our robust, scientific approach toward developing a rational phytotherapeutic product based on Centella asiatica for human investigation, addressing multiple factors to optimize its valid clinical evaluation. Specific aspects covered include approaches to identifying an optimal dose range for clinical assessment, design and composition of a dosage form and matching placebo, sourcing appropriate botanical raw material for product manufacture (including the evaluation of active compounds and contaminants), and up-scaling of laboratory extraction methods to available current Good Manufacturing Practice (cGMP) certified industrial facilities. We also address the process of obtaining regulatory approvals to proceed with clinical trials. Our study highlights the complexity of translational research on botanicals and the importance of identifying active compounds and developing sound analytical and bioanalytical methods for their determination in botanical materials and biological samples. Recent Phase I pharmacokinetic studies of our Centella asiatica product in humans (NCT03929250, NCT03937908) have highlighted additional challenges associated with designing botanical bioavailability studies, including specific dietary considerations that need to be considered.

Complementary and Alternative Medicine Online Learning Intervention for Oncology Healthcare Providers: A Mixed-Methods Study

Introduction:

With the increased usage of complementary approaches in oncology comes the need for its integration into healthcare professional (HCP) education. The purpose of this single-arm, mixed-methods study was to examine the feasibility and benefits of a brief complementary and alternative medicine (CAM) learning intervention for improving HCP knowledge, attitudes, and practices regarding CAM use in cancer care, and explore the experiences of participating HCPs.

Methods:

HCPs from the Tom Baker Cancer Centre in Alberta, Canada, were invited to participate in 3 online interactive learning modules that reviewed: (1) basic CAM information, (2) HCP-patient CAM communication, and (3) evidence-based CAM decision support. The study survey consisted of attitude (n = 14), knowledge (n = 31), and practice (n = 31) items, administered at baseline and two-months post-intervention. Semi-structured interviews were conducted with a subset of participants.

Results:

Approximately 300 HCPs were invited to participate, of which 105 expressed interest in the study (35%), and 83 of them consented to participate (79%). The intervention completion rate was 73% (61/83 HCPs). There was a significant pre-post change in HCPs’ attitudes and, to a lesser extent, knowledge and practices related to CAM (8/14 attitude items changed pre-post compared to 13/31 knowledge items and 5/31 practice items), in which more HCPs reported patients should be assisted in making complementary therapy (CT) decisions, exhibited greater knowledge about CAM, and more often engaged in a CAM-related clinical practice. Qualitative findings supported the beneficial effects of the modules, with HCPs describing themselves as being more likely to ask patients about their CAM use and referring them to credible CAM resources. Nonetheless, the majority did not feel adequately prepared to make recommendations about specific CTs, even after the intervention.

Conclusion:

The current study suggests that online CAM learning offers a feasible and potentially promising intervention for improving oncology HCP knowledge, attitudes, and practices regarding CAM, warranting further investigation. This study highlights a need for institutional resources to help HCPs fully integrate CT decision support into cancer patient care. A coordinated evidence-based CAM program at cancer centers may help ensure that all patients’ CAM-related needs are properly attended to.

Natural Products: Experimental Approaches to Elucidate Disposition Mechanisms and Predict Pharmacokinetic Drug Interactions

Natural products have been used by humans since antiquity for both egregious and beneficial purposes. Regarding the latter, these products have long been valued as a rich source of phytochemicals and developed into numerous life-saving pharmaceutical agents. Today, the sales and use of natural products with purported medicinal qualities continue to increase worldwide. However, natural products are not subject to the same premarket testing requirements as pharmaceutical agents, creating critical gaps in scientific knowledge about their optimal use. In addition, due to the common misperception that "natural" means "safe," patients may supplement or replace their prescription medications with natural products, placing themselves at undue risk for subefficacious pharmacotherapy or potentially toxic exposure. Collectively, with few exceptions, researchers, health care providers, and educators lack definitive information about how to inform consumers, patients, and students in the health professions on the safe and optimal use of these products. Recognition of this deficiency by key stakeholders, including the three pillars of biomedical research-industry, academia, and government-has facilitated multiple collaborations that are actively addressing this fundamental knowledge gap. This special issue contains a collection of articles highlighting the challenges faced by researchers in the field and the use of various experimental systems and methods to improve the mechanistic understanding of the disposition and drug interaction potential of natural products. Continued refinement of existing, and development of new, approaches will progress toward the common overarching goal of improving public health. SIGNIFICANCE STATEMENT: Natural products with purported medicinal value constitute an increasing share of the contemporary health care market. Natural products are not subject to the same premarket testing requirements as drug products, creating fundamental scientific knowledge gaps about the safe and effective use of these products. Collaborations among industrial, academic, and governmental researchers in multiple disciplines are anticipated to provide the definitive information needed to fill these gaps and improve public health.