The chemical interactome space between the human host and the genetically defined gut metabotypes

The bacteria that colonize the gastrointestinal tracts of mammals represent a highly selected microbiome that has a profound influence on human physiology by shaping the host's metabolic and immune system activity. Despite the recent advances on the biological principles that underlie microbial symbiosis in the gut of mammals, mechanistic understanding of the contributions of the gut microbiome and how variations in the metabotypes are linked to the host health are obscure. Here, we mapped the entire metabolic potential of the gut microbiome based solely on metagenomics sequencing data derived from fecal samples of 124 Europeans (healthy, obese and with inflammatory bowel disease). Interestingly, three distinct clusters of individuals with high, medium and low metabolic potential were observed. By illustrating these results in the context of bacterial population, we concluded that the abundance of the Prevotella genera is a key factor indicating a low metabolic potential. These metagenome-based metabolic signatures were used to study the interaction networks between bacteria-specific metabolites and human proteins. We found that thirty-three such metabolites interact with disease-relevant protein complexes several of which are highly expressed in cells and tissues involved in the signaling and shaping of the adaptive immune system and associated with squamous cell carcinoma and bladder cancer. From this set of metabolites, eighteen are present in DrugBank providing evidence that we carry a natural pharmacy in our guts. Furthermore, we established connections between the systemic effects of non-antibiotic drugs and the gut microbiome of relevance to drug side effects and health-care solutions.link_to_subscribed_fulltex

Inhibition of prenyltransferase activity by statins in both liver and muscle cell lines is not causative of cytotoxicity

As inhibitors of 3-hydroxy-3-methylglutaryl-CoA reductase, statins are an important first-line treatment for hypercholesterolemia. However, a recognized side-effect of statin therapy is myopathy, which in severe cases can present as potentially fatal rhabdomyolysis. This represents an important impediment to successful statin therapy, and despite decades of research the molecular mechanisms underlying this side-effect remain unclear. Current evidence supports a role for reduced levels of mevalonate pathway intermediates, with the most accepted hypothesis being a reduction in isoprenoids formation, leading to faulty post-translational modifications of membrane-associated proteins. We have undertaken a comprehensive analysis of the impact of nine statins on two human cell lines; Huh7 hepatoma and RD rhabdomyosarcoma. In both cell lines, concentration-dependent inhibition of prenylation was observed for cerivastatin and simvastatin, which could be rescued with the pathway intermediate mevalonate; in general, muscle cells were more sensitive to this effect, as measured by the levels of unprenylated Rap1A, a marker for prenylation by geranylgeranyl transferase I. Concentration-dependent toxicity was observed in both cell lines, with muscle cells again being more sensitive. Importantly, there was no correlation between inhibition of prenylation and cell toxicity, suggesting they are not causally linked. The lack of a causal relationship was confirmed by the absence of cytotoxicity in all cell lines following exposure to specific inhibitors of geranylgeranyl transferases I and II, and farnesyl transferase. As such, we provide strong evidence against the commonly accepted hypothesis linking inhibition of prenylation and statin-mediated toxicity, with the two processes likely to be simultaneous but independent

Simvastatin suppresses the differentiation of C2C12 myoblast cells via a Rac pathway.

Statins, which are known as cholesterol-lowering drugs, have several additional effects including the enhancement of bone formation and the stimulation of smooth muscle cell proliferation. In this study, we investigated the signal pathway of simvastatin operating in C2C12 myoblast cells. Myotube formation of C2C12 cells was efficiently blocked by 1 muM simvastatin, and mevalonic acid was able to cancel this effect. Geranylgeranyl pyrophosphate restored the myotube formation, whereas farnesyl pyrophosphate did not. These findings demonstrate that the Rho family, such as Rho, Rac and Cdc42, occurring downstream of geranylgeranyl pyrophosphate in the mevalonic acid pathway, was involved in the simvastatin-mediated blockage of myotube formation. An inhibitor of Rho kinase did not influence the myotube formation; whereas an inhibitor of Rac blocked this process. Taken together, we conclude that the differentiation of C2C12 cells into myotubes was blocked by simvastatin through the pathway mediated by Rac, not by Rho

Construction of a system for determining the difficulty of medical terms in patient documents

患者から「医師や薬剤師が使う言葉が難しい」「説明文を読んでも理解できない」といった訴えを聞くことがある。そこで、難易度評価試験を実施し、データを分析することで、患者向け文書で使われる「医療用語を含む文章」を、医療知識のない人でも理解できる「わかりやすい文章」に変更するシステムを作成することを目的にした。165単語中無作為に20単語を抽出して医療者, 薬学生, 一般に行ったテストデータを解析し、特異的パターンを示す14単語を抽出した。この14単語についてフォーカスグループによるインタビュー調査を実施したところ、単語単独の意味ではなく、複合語に関しての理解しづらさを感じていることが明らかとなった。We sometimes hear complaints from patients that the language used by doctors and pharmacists is difficult or that they cannot understand the explanatory text. Therefore, we conducted a difficulty evaluation test and analyzed the data to create a system to change "sentences containing medical terms" used in documents for patients into "easy-to-understand sentences" that can be understood even by users without medical knowledge. Quiz response data from medical professionals, pharmacy students, and the general public were analyzed to identify 14 words that exhibit specific patterns. Focus group interviews were conducted with these 14 words, which revealed that respondents had more difficulty understanding compound words than the meaning of each word alone.研究分野：医療統計学，データサイエン