Pharmacokinetics and immunomodulatory effect of lipophilic Echinacea extract formulated in softgel capsules

A systematic review on the effects of Echinacea supplementation on cytokine levels: Is there a role in COVID-19?

COVID-19 is the respiratory illness caused by the novel coronavirus, SARS-CoV-2. Cytokine storm appears to be a factor in COVID-19 mortality. Echinacea species have been used historically for immune modulation. A previous rapid review suggested that Echinacea supplementation may decrease the levels of pro-inflammatory cytokines involved in cytokine storm. The objective of the present systematic review was to identify all research that has assessed changes in levels of cytokines relevant to cytokine storm in response to administration of Echinacea supplementation. The following databases were searched: Medline (Ovid), AMED (Ovid), CINAHL (EBSCO), EMBASE (Ovid). Title and abstract screening, full text screening, and data extraction were completed in duplicate using a piloted extraction template. Risk of bias assessment was completed. Qualitative analysis was used to assess for trends in cytokine level changes. The search identified 279 unique publications. After full text screening, 105 studies met criteria for inclusion including 13 human studies, 24 animal studies, and 71 in vitro or ex vivo studies. The data suggest that Echinacea supplementation may be associated with a decrease in the pro-inflammatory cytokines IL-6, IL-8, and TNF, as well as an increase in the anti-inflammatory cytokine IL-10. The risk of bias in the included studies was generally high. While there is currently no substantive research on the therapeutic effects of Echinacea in the management of either cytokine storm or COVID-19, the present evidence related to the herb's impact on cytokine levels suggests that further research may be warranted in the form of a clinical trial involving patients with COVID-19.

Echinacea angustifolia DC. Lipophilic Extract Patch for Skin Application: Preparation, In Vitro and In Vivo Studies

Dodeca-2E,4E,8Z,10E/Z-tetraenoic isobutylamide (tetraene) is the main component of Echinacea angustifolia DC. lipophilic extract, the bioavailability and immunomodulatory effect after oral administration in soft gel capsules in healthy volunteers of which we have already demonstrated. In the present work, we assessed the transdermal administration as an alternative route of administration of such an alkamide. The first step, therefore, encompassed the preparation of a drug-in-adhesive patch with an area of 868 mm² and containing a dose of 0.64 mg of tetraene. In vitro skin permeation studies in Franz-type diffusion chambers resulted in a tetraene flux of (103 ± 10) ng × cm⁻² × h⁻¹ with a very good linearity (r = 0.99). The relatively low lag time of just 13 min indicates low binding and the accumulation of tetraene in the skin. Finally, the patch was administered to six healthy volunteers, and the pharmacokinetic analysis was performed by nonlinear mixed effects modelling with soft gel oral capsules serving as the reference formulation. The in vivo results correlated well with the in vitro permeation and indicated an initial burst tetraene absorption from the patch that was in parallel with the zero-order kinetics of absorption. The rate of the latter process was in good agreement with the one estimated in vitro. The tetraene absorption rate was therefore slow and prolonged with time, resulting in a bioavailability of 39% relative to the soft gel capsules and a very flat plasma concentration profile.

The effect of Echinacea spp. on the prevention or treatment of COVID-19 and other respiratory tract infections in humans: A rapid review

Brief overview

Current evidence suggests that Echinacea supplementation may decrease the duration and severity of acute respiratory tract infections; however, no studies using Echinacea in the prevention or treatment of conditions similar to COVID-19 have been identified. Few adverse events were reported, suggesting that this herbal therapy is reasonably safe. Because Echinacea can increase immune function, there is a concern that it could worsen over-activation of the immune system in cytokine storm; however, clinical trials show that Echinacea decreases levels of immune molecules involved in cytokine storm.

Verdict

Echinacea supplementation may assist with the symptoms of acute respiratory infections (ARI) and the common cold, particularly when administered at the first sign of infection; however, no studies using Echinacea in the prevention or treatment of conditions similar to COVID-19 have been identified. Previous studies have reported that Echinacea may decrease the severity and/or duration of ARI when taken at the onset of symptoms. The studies reporting benefit used E. purpurea or a combination of E. purpurea and E. angustifolia containing standardized amounts of active constituents.Few adverse events from the use of Echinacea were reported, suggesting that this herbal therapy is reasonably safe. No human trials could be located reporting evidence of cytokine storm when Echinacea was used for up to 4 months.When assessing all human trials which reported changes in cytokine levels in response to Echinacea supplementation, the results were largely consistent with a decrease in the pro-inflammatory cytokines that play a role in the progression of cytokine storm and Acute Respiratory Distress Syndrome (ARDS), factors that play a significant role in the death of COVID-19 patients. While there is currently no research on the therapeutic effects of Echinacea in the management of cytokine storm, this evidence suggests that further research is warranted.

Combined extracts of Echinacea angustifolia DC. and Zingiber officinale Roscoe in softgel capsules: Pharmacokinetics and immunomodulatory effects assessed by gene expression profiling

BACKGROUND AND OBJECTIVE

Echinacea angustifolia DC. and Zingiber officinale Roscoe are two natural products with documented immunomodulatory activity, both able to modulate the expression of important immune-related genes. Thus, their use in combination seems to be particularly promising. In this context, we have considered the oral supplementation of a highly standardized lipophilic extract combining both above-mentioned phytocomplexes, formulated in attractive softgel capsules, with two objectives: on the one hand to study oral pharmacokinetic of main active extracts' components and on the other hand to examine the immunomodulation and anti-inflammatory properties by gene expression profiling.

METHODS

Softgel capsules containing a combination of E. angustifolia DC. and Z. officinale Roscoe (5 mg and 25 mg, respectively) were given by oral administration to 10 healthy volunteers. The plasma concentrations of dodeca-2E,4E,8Z,10E/Z-tetraenoic isobutylamide (tetraene) for E. angustifolia DC., 6-gingerol and 6-shogaol (free and glucuronide) for Z. officinale Roscoe were determined by LC-MS analysis, and the pharmacokinetic analysis was performed. To understand the functional mechanisms responsible for the documented health benefits, we also examined the overall transcriptional remodeling induced in the peripheral blood mononuclear cells and performed an integrative functional analysis on the generated gene expression.

RESULTS

All bioactive components were absorbed very rapidly, and their tmax were detected in plasma from 30 min to 1.40 h. The peak concentrations of tetraene, 6-gingerol, 6-shogaol and their glucuronide metabolites were 14.74, 5.66, 9.25, 29.2 and 22.24 ng/ml, respectively. Integrated analysis performed on the generated gene expression data highlighted immunomodulatory and anti-inflammatory effects similar to those exerted by hydrocortisone.

CONCLUSION

These data demonstrated that the bioactive ingredients are highly and rapidly absorbed from softgel capsules containing the combination of the above-mentioned lipophilic extracts, providing evidence to support their immunomodulatory and anti-inflammatory properties. These data also help in defining the mechanistic pathways underlying the health benefits of these plant-derived bioactive compounds.

The effect and safety of highly standardized Ginger (Zingiber officinale) and Echinacea (Echinacea angustifolia) extract supplementation on inflammation and chronic pain in NSAIDs poor responders. A pilot study in subjects with knee arthrosis

The study aimed to evaluate the effect of Zingiber officinale and Echinacea angustifolia extract supplementation (25 mg of ginger and 5 mg of Echinacea) for 30 days on inflammation and chronic pain in knee osteoarthritis (OA). Consecutive nonsteroidal anti-inflammatory-drugs (NSAIDs) poor responders with chronic inflammation and pain due to knee arthrosis were assessed (15 subjects, age: 67.2 ± 7.9, body mass index: 30.6 ± 7.1, men/women:2/13). The primary endpoint was to determine pain improvement from baseline to Day 30 by Tegner Lysholm Knee Scoring. The secondary endpoints were the assessment of Visual Analog Scale for Pain, health-related quality of life, by the ShortForm36 (SF-36), anthropometric parameters, hydration. After supplementation, a significant improvement of 12.27 points was observed for Lysholm scale score (p < 0.05), SF-36 (p < 0.05), and a decrease in -0.52 cm in knee circumference (left) (p < 0.01). This pilot study provides feasibility and safety data for the use of highly standardised ginger and Echinacea extract supplementation in people with knee OA.