Evaluation of Natural and Botanical Medicines for Activity Against Growing and Non-growing Forms of B. burgdorferi

Abstract

Lyme disease is the most common vector-borne disease in the US and Europe. Although the current recommended Lyme antibiotic treatment is effective for the majority of Lyme disease patients, about 10-20% of patients continue to suffer from persisting symptoms. There have been various anecdotal reports on the use of herbal extracts for treating patients with persisting symptoms with varying degree of improvements. However, it is unclear whether the effect of the herb products is due to their direct antimicrobial activity or their effect on host immune system. In the present study, we investigated the antimicrobial effects of 12 commonly used botanical medicines and three other natural antimicrobial agents for potential anti-Borrelia burgdorferi activity in vitro. Among them, 7 natural product extracts at 1% were found to have good activity against the stationary phase B. burgdorferi culture compared to the control antibiotics doxycycline and cefuroxime. These active botanicals include Cryptolepis sanguinolenta, Juglans nigra (Black walnut), Polygonum cuspidatum (Japanese knotweed), Artemisia annua (Sweet wormwood), Uncaria tomentosa (Cat's claw), Cistus incanus, and Scutellaria baicalensis (Chinese skullcap). In contrast, Stevia rebaudiana, Andrographis paniculata, Grapefruit seed extract, colloidal silver, monolaurin, and antimicrobial peptide LL37 had little or no activity against stationary phase B. burgdorferi. The minimum inhibitory concentration (MIC) values of Artemisia annua, Juglans nigra, and Uncaria tomentosa were quite high for growing B. burgdorferi, despite their strong activity against the non-growing stationary phase B. burgdorferi. On the other hand, the top two active herbs, Cryptolepis sanguinolenta and Polygonum cuspidatum, showed strong activity against both growing B. burgdorferi (MIC = 0.03-0.06% and 0.25-0.5%, respectively) and non-growing stationary phase B. burgdorferi. In subculture studies, only 1% Cryptolepis sanguinolenta extract caused complete eradication, while doxycycline and cefuroxime and other active herbs could not eradicate B. burgdorferi stationary phase cells as many spirochetes were visible after 21-day subculture. Further studies are needed to identify the active constituents of the effective botanicals and evaluate their combinations for more effective eradication of B. burgdorferi in vitro and in vivo. The implications of these findings for improving treatment of persistent Lyme disease are discussed.

Evaluation of Disulfiram Drug Combinations and Identification of Other More Effective Combinations against Stationary Phase Borrelia burgdorferi

“…The Cmax concentration we used was taken from a pharmacokinetic study in mice. We realize that the Cmax concentration we used in this study for Cry was extremely low (0.024 µg/mL) when compared to all other antibiotics tested and that the study from which we took the Cmax value was conducted with only two mice [33]. We think further pharmacokinetic studies of Cry should be performed in order to evaluate a more exact Cmax value, evaluate the potential toxicity of this compound, and determine its potential use for LD.…”

Botanical Medicines Cryptolepis sanguinolenta, Artemisia annua, Scutellaria baicalensis, Polygonum cuspidatum, and Alchornea cordifolia Demonstrate Inhibitory Activity Against Babesia duncani

“…Research over the past few decades has demonstrated that many botanical medicines have antimicrobial, antiparasitic, and anticancer activity ( Tagboto and Townson, 2001 ; Shoemaker et al., 2005 ; Feng et al., 2011 ). In our previous study, we identified seven herbal medicines that have good activity against stationary phase Borrelia burgdorferi compared to the control antibiotics used in clinical treatment ( Feng J. et al., 2020 ). In humans, Babesia spp.…”

“…These findings indicated that natural products extracted from plants and herbs may serve as a potential source of promising compounds for anti-parasitic drugs. In this current study, we used the same hamster erythrocyte model to screen for inhibition of B. duncani using a panel of 46 herbal medicine extracts, many of which are useful in the treatment of babesiosis and related conditions according to the Buhner book on herbal medicines ( Buhner, 2015 ) or were shown in our previous in vitro studies to have antimicrobial effects ( Feng J. et al., 2020 ). Our results identified Cryptolepis sanguinolenta, Artemisia annua, Scutellaria baicalensis, Alchornea cordifolia , and Polygonum cuspidatum and their bioactive compounds as having good activity against B. duncani .…”

Supporting patients with long-term problems after Lyme disease

“…The authors concluded that future studies should be directed at identifying the active constituents of each botanical, evaluating synergistic combinations, and confirming their safety and efficacy. 13 Continuing with antibiotic treatment may affect the immune system in a variety of other ways. Bernardino et al did a study on monkey brain cells stimulated with LD bacteria and showed that doxycycline moderated the inflammatory response.…”

“…The authors concluded that future studies should be directed at identifying the active constituents of each botanical, evaluating synergistic combinations, and confirming their safety and efficacy. 13 …”