A genetic locus complements resistance to Bordetella pertussis-induced histamine sensitization

Histamine plays pivotal role in normal physiology and dysregulated production of histamine or signaling through histamine receptors (HRH) can promote pathology. Previously, we showed that Bordetella pertussis or pertussis toxin can induce histamine sensitization in laboratory inbred mice and is genetically controlled by Hrh1/HRH1. HRH1 allotypes differ at three amino acid residues with P263-V313-L331 and L263-M313-S331, imparting sensitization and resistance respectively. Unexpectedly, we found several wild-derived inbred strains that carry the resistant HRH1 allotype (L263-M313-S331) but exhibit histamine sensitization. This suggests the existence of a locus modifying pertussis-dependent histamine sensitization. Congenic mapping identified the location of this modifier locus on mouse chromosome 6 within a functional linkage disequilibrium domain encoding multiple loci controlling sensitization to histamine. We utilized interval-specific single-nucleotide polymorphism (SNP) based association testing across laboratory and wild-derived inbred mouse strains and functional prioritization analyses to identify candidate genes for this modifier locus. Atg7, Plxnd1, Tmcc1, Mkrn2, Il17re, Pparg, Lhfpl4, Vgll4, Rho and Syn2 are candidate genes within this modifier locus, which we named Bphse, enhancer of Bordetella pertussis induced histamine sensitization. Taken together, these results identify, using the evolutionarily significant diversity of wild-derived inbred mice, additional genetic mechanisms controlling histamine sensitization.

Ergot alkaloids in sclerotia collected in Japan: synthetic profiles and induction of apoptosis by Clavine-type compounds

The genus Claviceps (Clavicipitaceae) is famous for producing ergot alkaloids (EAs) in sclerotia. EAs can cause ergotism, resulting in convulsions and necrosis when ingested, making these compounds a serious concern for food safety. Agroclavine (2), a typical Clavine-type EA, is a causative agent of ergotism and is listed as a compound to be monitored by the European Food Safety Authority. Clavine-type EAs are known to cause cytotoxicity, but the mechanism has not been elucidated. We performed annexin V and PI double-staining followed by flow cytometric analysis to detect apoptosis in HepG2 and PANC-1 cells after exposure to Clavine-type EAs. Clavine-type EAs reduced cell viability and induced apoptosis in both cell lines. We then performed LC-MS analysis of EAs from 41 sclerotia samples of Claviceps collected in Japan. 24 out of 41 sclerotia extracts include peptide-type EAs (ergosine/inine: 4/4', ergotamine: 5, ergocornine/inine: 6/6', α-ergocryptine/inine: 8/8', and ergocristine/inine: 9/9') and 19 sclerotia extracts among 24 sclerotia detected peptide type EAs include Clavine-type EAs (pyroclavine: 1, agroclavine: 2, festuclavine: 3) by LC-MS. We then performed a metabolomic analysis of the EAs in the sclerotia using principal component analysis (PCA). The PCA score plots calculated for EAs suggested the existence of four groups with different EA production patterns. One of the groups was formed by the contribution of Clavine-type EAs. These results suggest that Clavine-type EAs are a family of compounds requiring attention in food safety and livestock production in Japan.

The history of labour induction: How did we get here?

The mean duration of human pregnancy is 280 days but the range is wide, and "term" has been defined to range from 37 to 42 weeks. In the 18th and 19th centuries, labour induction was used mainly in cases of pelvic deformity, before the foetus grew too large to be delivered. Induction methods were unreliable until the 20th century, when pituitary extract, and then synthetic oxytocin and prostaglandins, became available. "Disproportion" was the leading indication for induction until the 1950s, when it became clear that prolonged pregnancy was associated with increased perinatal mortality. Pregnancy dating was improved by ultrasound, which also showed that foetal growth slows at term. Induction rates rose during the 1970s, causing public concern about obstetric intervention. In the 21st century, large-scale randomised trials showed that perinatal mortality is lowest at 39-40 weeks, and that induction at that time does not increase the rate of operative delivery.

Why Are the Majority of Active Compounds in the CNS Domain Natural Products? A Critical Analysis

Small-molecule natural products (NPs) have a long and successful track record of providing first-in-class drugs and pharmacophore (scaffolds) in all therapeutic areas, serving as a bridge between modern and traditional medicine. This trajectory has been remarkably successful in three key areas of modern therapeutics: cancers, infections, and CNS diseases. Beginning with the discovery of morphine 200 years ago, natural products have remained the primary source of new drugs/scaffolds for CNS diseases. In this perspective, we address the question: why are the majority of active compounds in the CNS domain natural products? Our analysis indicates that ∼84% approved drugs for CNS diseases are NPs or NP-inspired, and interestingly, 20 natural products provided more than 400 clinically approved CNS drugs. We have discussed unique physicochemical properties of NPs and NP-inspired vis-à-vis synthetic drugs, isoform selectivity, and evolutionary relationship, providing a rationale for increasing focus on natural product driven discovery for next-generation drugs for neurodegenerative diseases.

Recent progress in ergot alkaloid research

Ergot alkaloids are a class of indole derivatives produced by the genera of Ascomycota includingClaviceps,Aspergillus,Penicillium, andEpichloë.

Total synthesis, biosynthesis and biological profiles of clavine alkaloids

This review highlights noteworthy synthetic and biological aspects of the clavine subfamily of ergot alkaloids. Recent biosynthetic insights have laid the groundwork for a better understanding of the diverse biological pathways leading to these indole derivatives. Ergot alkaloids were among the first fungal-derived natural products identified, inspiring pharmaceutical applications in CNS disorders, migraine, infective diseases, and cancer. Pergolide, for example, is a semi-synthetic clavine alkaloid that has been used to treat Parkinson's disease. Synthetic activities have been particularly valuable to facilitate access to rare members of the Clavine family and empower medicinal chemistry research. Improved molecular target identification tools and a better understanding of signaling pathways can now be deployed to further extend the biological and medical utility of Clavine alkaloids.

Biology, genetics, and management of ergot (Claviceps spp.) in rye, sorghum, and pearl millet

Ergot is a disease of cereals and grasses caused by fungi in the genus Claviceps. Of particular concern are Claviceps purpurea in temperate regions, C. africana in sorghum (worldwide), and C. fusiformis in pearl millet (Africa, Asia). The fungi infect young, usually unfertilized ovaries, replacing the seeds by dark mycelial masses known as sclerotia. The percentage of sclerotia in marketable grain is strictly regulated in many countries. In winter rye, ergot has been known in Europe since the early Middle Ages. The alkaloids produced by the fungus severely affect the health of humans and warm-blooded animals. In sorghum and pearl millet, ergot became a problem when growers adopted hybrid technology, which increased host susceptibility. Plant traits reducing ergot infection include immediate pollination of receptive stigmas, closed flowering (cleistogamy), and physiological resistance. Genetic, nonpollen-mediated variation in ergot susceptibility could be demonstrated in all three affected cereals. Fungicides have limited efficacy and application is weather dependent. Sorting out the sclerotia from the harvest by photocells is expensive and time consuming. In conclusion, molecular-based hybrid rye breeding could improve pollen fertility by introgressing effective restorer genes thus bringing down the ergot infection level to that of conventional population cultivars. A further reduction might be feasible in the future by selecting more resistant germplasm.

Pediatric ergot alkaloid exposures reported to the California Poison Control System: 1997-2008

CONTEXT

The risk of toxicity from exposure to ergot alkaloid-containing medications in children is uncertain. Due to the alarming historical experience with severe toxicity and the syndrome of ergotism from natural and synthetic ergot alkaloids, triage recommendations for pediatric exposures to medicinal agents containing ergot alkaloids may be inappropriate and inconsistent.

OBJECTIVES

The goal of this study was to describe the clinical effects of unintentional ergot alkaloid exposures in children and to identify the need for hospitalization in these cases.

METHODS

This was a retrospective cohort study of all pediatric (< 7 years old) ergot alkaloid exposures reported to the California Poison Control System (CPCS) from 1997 to 2008. Case narratives were reviewed and assessed for patient demographics, ergot alkaloid agent and dose, route of and reason for exposure, symptoms, therapy, hospitalization period, and final outcome.

RESULTS

Of the 374 cases, 353 met the inclusion criteria. The median age was 24 months (Range: 7-72 months) with more than 99% oral route of exposure. The most frequent clinical effect was gastrointestinal distress (16%), followed by lethargy (5%). Two cases with significant vascular and CNS symptoms were identified, both with complete recovery. For symptomatic patients, all symptoms were there at time of initial presentation. The majority, 62%, of all patients were treated in the hospital setting. The median length of hospital stay was 4 h (Range: 1-36 h). Ergot exposures had a similar number of serious outcomes (moderate or worse effects) compared to all other pediatric poisonings reported to the CPCS during the study period (odds ratio [OR], 0.98; 95% confidence interval [CI], 0.25-3.95), but were associated with a disproportionately higher number of hospitalizations (OR, 13.8; 95% CI, 11.1-17.1).

CONCLUSIONS

Pediatric ergot exposures were associated with few transient adverse effects but multiple hospitalizations. Rare cases of significant toxicity associated with methylergonovine exposures were found. Current poison control send-in protocols and emergency department (ED) guidelines should consider home management and short ED stays as opposed to lengthy critical care bed admissions.

Production, detection, and purification of clavine-type ergot alkaloids

Ergot alkaloids are indole derivatives with diverse structures and biological activities. This chapter describes the procedure from fungal cultivation to purified ergot alkaloids, as exemplified by fumigaclavine A in Penicillium commune. Furthermore, useful notes for working with purified ergot alkaloids are given.