Data Mining a Medieval Medical Text Reveals Patterns in Ingredient Choice That Reflect Biological Activity against Infectious Agents

We used established methodologies from network science to identify patterns in medicinal ingredient combinations in a key medieval text, the 15th-century Lylye of Medicynes, focusing on recipes for topical treatments for symptoms of microbial infection. We conducted experiments screening the antimicrobial activity of selected ingredients. These experiments revealed interesting examples of ingredients that potentiated or interfered with each other’s activity and that would be useful bases for future, more detailed experiments. Our results highlight (i) the potential to use methodologies from network science to analyze medieval data sets and detect patterns of ingredient combination, (ii) the potential of interdisciplinary collaboration to reveal different aspects of the ethnopharmacology of historical medical texts, and (iii) the potential development of novel therapeutics inspired by premodern remedies in a time of increased need for new antibiotics.The pharmacopeia used by physicians and laypeople in medieval Europe has largely been dismissed as placebo or superstition. While we now recognize that some of the materia medica used by medieval physicians could have had useful biological properties, research in this area is limited by the labor-intensive process of searching and interpreting historical medical texts. Here, we demonstrate the potential power of turning medieval medical texts into contextualized electronic databases amenable to exploration by the use of an algorithm. We used established methodologies from network science to reveal patterns in ingredient selection and usage in a key text, the 15th-century Lylye of Medicynes, focusing on remedies to treat symptoms of microbial infection. In providing a worked example of data-driven textual analysis, we demonstrate the potential of this approach to encourage interdisciplinary collaboration and to shine a new light on the ethnopharmacology of historical medical texts

The Antituberculosis Drug Ethambutol Selectively Blocks Apical Growth in CMN Group Bacteria

Members of the genus Mycobacterium are the most prevalent cause of infectious diseases. Mycobacteria have a complex cell envelope containing a peptidoglycan layer and an additional arabinogalactan polymer to which a mycolic acid bilayer is linked;this complex, multilayered cell wall composition (mAGP) is conserved among all CMN group bacteria. The arabinogalactan and mycolic acid synthesis pathways constitute effective drug targets for tuberculosis treatment. Ethambutol (EMB), a classical antituberculosis drug, inhibits the synthesis of the arabinose polymer. Although EMB acts bacteriostatically, its underlying molecular mechanism remains unclear. Here, we used Corynebacterium glutamicum and Mycobacterium phlei as model organisms to study the effects of EMB at the single-cell level. Our results demonstrate that EMB specifically blocks apical cell wall synthesis, but not cell division, explaining the bacteriostatic effect of EMB. Furthermore, the data suggest that members of the family Corynebacterineae have two dedicated machineries for cell elongation (elongasome) and cytokinesis (divisome). IMPORTANCE Antibiotic treatment of bacterial pathogens has contributed enormously to the increase in human health. Despite the apparent importance of antibiotic treatment of bacterial infections, surprisingly little is known about the molecular functions of antibiotic actions in the bacterial cell. Here, we analyzed the molecular effects of ethambutol, a first-line antibiotic against infections caused by members of the genus Mycobacterium. We find that this drug selectively blocks apical cell growth but still allows for effective cytokinesis. As a consequence, cells survive ethambutol treatment and adopt a pneumococcal cell growth mode with cell wall synthesis only at the site of cell division. However, combined treatment of ethambutol and beta-lactam antibiotics acts synergistically and effectively stops cell proliferation

In Vitro Antimycobacterial Activities of Capuramycin Analogues▿

Translocase I inhibitor compounds derived from capuramycin demonstrated rapid bactericidal activity against several different mycobacterial species. SQ641 was the most active of the compounds, with a MIC of 0.12 to 8 μg/ml, a postantibiotic effect of 55 h, and interesting synergistic effects with other antitubercular drugs

In Vitro Interactions between New Antitubercular Drug Candidates SQ109 and TMC207▿

The in vitro interactions of two new antitubercular drugs, SQ109 and TMC207, with each other and with rifampin (RIF) were evaluated. The combination of SQ109 with TMC207 (i) improved an already excellent TMC207 MIC for M. tuberculosis H37Rv by 4- to 8-fold, (ii) improved the rate of killing of bacteria over the rate of killing by each single drug, and (iii) enhanced the drug postantibiotic effect by 4 h. In no instance did we observe antagonistic activities with the combination of SQ109 and TMC207. Rifampin activates cytochrome P450 genes to reduce the area under the curve (AUC) for TMC207 in humans. The presence of RIF in three-drug combinations did not affect the synergistic activities of SQ109 and TMC207, and SQ109 also dramatically decreased the MIC of RIF. SQ109 was active by itself, and both its activity was improved by and it improved the in vitro activities of both RIF and TMC207

Entamoeba histolytica-Induced Mucin Exocytosis Is Mediated by VAMP8 and Is Critical in Mucosal Innate Host Defense

Intestinal mucus secretion is critical in maintaining mucosal host defense against a myriad of pathogens by preventing direct association with the epithelium. Entamoeba histolytica specifically binds colonic MUC2 mucin and also induces potent hypersecretion from goblet cells; however, characterization of the nature of the mechanisms controlling mucus release remains elusive. In this report, we identify vesicle SNARE vesicle-associated membrane protein 8 (VAMP8) present on mucin granules as orchestrating regulated exocytosis in human goblet cells in response to the presence of E. histolytica. VAMP8 was specifically activated during E. histolytica infection, and ablation of VAMP8 led to impaired mucin secretion. As a consequence, loss of VAMP8 increased E. histolytica adherence to epithelial cells associated with enhanced cell death through apoptosis characterized by caspase 3 and 9 cleavages and DNA fragmentation. With the mucosal barrier compromised in Vamp8−/− animals, E. histolytica induced an aggressive proinflammatory response with elevated levels of interleukin-1 alpha (IL-1α), IL-1β, and tumor necrosis factor alpha (TNF-α) secretion. This report is the first to characterize regulated mucin exocytosis in intestinal goblet cells in response to a pathogen and the downstream consequences of improper mucin secretion in mucosal barrier defense

Structure, in Vivo Detection and Anti-Bacterial Activity of Metabolites of SQ109, an Anti-Infective Drug Candidate

SQ109 is a drug candidate for the treatment of tuberculosis (TB). It is thought to target primarily the protein MmpL3 in Mycobacterium tuberculosis, but it also inhibits the growth of some other bacteria, as well as fungi and protozoa. SQ109 is metabolized by the liver, and it has been proposed that some of its metabolites might be responsible for its activity against TB. Here, we synthesized six potential P450 metabolites of SQ109 and used these as well as 10 other likely metabolites as standards in a mass spectrometry study of M. tuberculosis-infected rabbits treated with SQ109, in addition to testing all 16 putative metabolites for anti-bacterial activity. We found that there were just two major metabolites in lung tissue: a hydroxy-adamantyl analog of SQ109 and N’-adamantylethylenediamine. Neither of these, or the other potential metabolites tested, inhibited the growth of M. tuberculosis, or of M. smegmatis, Bacillus subtilis or E. coli, making it unlikely that an SQ109 metabolite contributes to its anti-bacterial activity. In the rabbit TB model, it is thus the gradual accumulation of non-metabolized SQ109 in tissues to therapeutic levels that leads to good efficacy. Our results also provide new insights into how SQ109 binds to its target MmpL3, based on our mass spectroscopy results which indicate that the charge in SQ109 is primarily localized on the geranyl nitrogen, explaining the very short distance to a key Asp found in the X-ray structure of SQ109 bound to MmpL3. Our results also suggest that it is intact SQ109 that is likely to target some of the other bacteria, fungi and protozoa in which MmpL3-like proteins have recently been reported.</p

Activity of SQ641, a Capuramycin Analog, in a Murine Model of Tuberculosis ▿

New delivery vehicles and routes of delivery were developed for the capuramycin analogue SQ641. While this compound has remarkable in vitro potency against Mycobacterium tuberculosis, it has low solubility in water and poor intracellular activity. We demonstrate here that SQ641 dissolved in the water-soluble vitamin E analogue α-tocopheryl polyethylene glycol 1000 succinate (TPGS) or incorporated into TPGS-micelles has significant activity in a mouse model of tuberculosis

A bioengineered three-dimensional cell culture platform integrated with microfluidics to address antimicrobial resistance in tuberculosis

Antimicrobial resistance presents one of the most significant threats to human health, with the emergence of totally drug-resistant organisms. We have combined bioengineering, genetically modified bacteria, longitudinal readouts, and fluidics to develop a transformative platform to address the drug development bottleneck, utilizing Mycobacterium tuberculosis as the model organism. We generated microspheres incorporating virulent reporter bacilli, primary human cells, and an extracellular matrix by using bioelectrospray methodology. Granulomas form within the three-dimensional matrix, and mycobacterial stress genes are upregulated. Pyrazinamide, a vital first-line antibiotic for treating human tuberculosis, kills M. tuberculosis in a three-dimensional culture but not in a standard two-dimensional culture or Middlebrook 7H9 broth, demonstrating that antibiotic sensitivity within microspheres reflects conditions in patients. We then performed pharmacokinetic modeling by combining the microsphere system with a microfluidic plate and demonstrated that we can model the effect of dynamic antibiotic concentrations on mycobacterial killing. The microsphere system is highly tractable, permitting variation of cell content, the extracellular matrix, sphere size, the infectious dose, and the surrounding medium with the potential to address a wide array of human infections and the threat of antimicrobial resistance