Revascularization in advanced stable coronary artery disease

Complex Interplay between Sphingolipid and Sterol Metabolism Revealed by Perturbations to the Leishmania Metabolome Caused by Miltefosine

With the World Health Organization reporting over 30,000 deaths and 200,000 to 400,000 new cases annually, visceral leishmaniasis is a serious disease affecting some of the world's poorest people. As drug resistance continues to rise, there is a huge unmet need to improve treatment. Miltefosine remains one of the main treatments for leishmaniasis, yet its mode of action (MoA) is still unknown. Understanding the MoA of this drug and parasite response to treatment could help pave the way for new and more successful treatments for leishmaniasis. A novel method has been devised to study the metabolome and lipidome of Leishmania donovani axenic amastigotes treated with miltefosine. Miltefosine caused a dramatic decrease in many membrane phospholipids (PLs), in addition to amino acid pools, while sphingolipids (SLs) and sterols increased. Leishmania major promastigotes devoid of SL biosynthesis through loss of the serine palmitoyl transferase gene (ΔLCB2) were 3-fold less sensitive to miltefosine than wild-type (WT) parasites. Changes in the metabolome and lipidome of miltefosine-treated L. major mirrored those of L. donovani A lack of SLs in the ΔLCB2 mutant was matched by substantial alterations in sterol content. Together, these data indicate that SLs and ergosterol are important for miltefosine sensitivity and, perhaps, MoA.

Technosphere/Insulin--a new approach for effective delivery of human insulin via the pulmonary route

The development of pulmonary insulin formulation offers an attractive alternative to the current requirement of repeated subcutaneous (s.c.) injections for insulin administration. Technosphere/Insulin is a formulation of regular human insulin that was designed to produce an efficient transport of insulin across the respiratory epithelium into the systemic circulation. Several studies using the euglycemic clamp technique were performed in healthy volunteers and patients with Type 2 diabetes to assess the pharmacokinetic and pharmacodynamic properties of Technosphere/Insulin. The investigations revealed a very rapid systemic insulin uptake (insulin T(max) approximately 12-14 min), a fast onset of action (maximum activity approximately 20-30 min), and a short duration of action (approximately 2-3 h) in healthy volunteers and in patients with Type 2 diabetes. In the first study, employing a commercially available inhaler, the relative bioavailability (compared with s.c. injections) was initially reported to be 26% for the first 3 h and 16% for the entire observation period of 6 h. With the development of a specific inhaler adapted to the physical properties of Technosphere/Insulin, the MedTone Inhaler, relative bioavailability was 50% for the first 3 h and 30% over the entire 6-h period. A clear linearity of systemic insulin uptake was observed in a study employing 12 healthy volunteers inhaling doses of 25, 50, and 100 IU. Repeated inhalation of 100 IU of Technosphere/Insulin by 12 patients with Type 2 diabetes revealed a lower variability in comparison with published s.c. injection data from healthy volunteers. This new Technosphere/Insulin formulation was well tolerated, and no serious adverse events were reported in any of the investigations. Given its attractive time-action profile, Technosphere/Insulin may become a suitable alternative to s.c. injection for prandial insulin delivery, especially in patients with Type 2 diabetes, if the long-term safety, tolerability, and efficacy of this pulmonary insulin are established and confirmed in future studies.

Metabolic effects of dental resin components in vitro detected by NMR spectroscopy

Earlier studies have shown that the comonomer triethyleneglycol-dimethacrylate (TEGDMA) and the photostabilizer 2-hydroxy-4-methoxybenzophenone (HMBP) are cytotoxic and inhibit cell growth. It was the aim of this study to elucidate the underlying metabolic effects of TEGDMA and HMBP on immortal contact-inhibited Swiss albino mouse embryo cells (3T3 fibroblasts) by nuclear magnetic resonance (NMR) spectroscopy. Cell extracts and culture media were analyzed by NMR spectroscopy for metabolic changes after incubation for 24 hours with ED20-concentrations of TEGDMA and HMBP. TEGDMA could be detected in all fractions (cytosol, lipid fractions, and culture media) of 3T3 cells, while HMBP was found only in the lipid fraction accumulated at a maximum rate (51 nmol/mg DNA) compared with TEGDMA (27 nmol/mg DNA). TEGDMA increased the concentration of phosphomonoesters to 180+/-36% and decreased the phosphodiesters to 65+/-5% of controls (control = 100%). Thus, the turnover of phospholipids was enhanced, whereas content and composition of phospholipids of membranes did not alter markedly. Additionally, TEGDMA changed the metabolic state of cells, indicated by slight decreases of nucleoside triphosphates and an increase in the ratio of nucleoside diphosphates to nucleoside triphosphates, while HMBP had no effect. The most remarkable effect of TEGDMA was a nearly complete decline of the intracellular glutathione levels. Analysis of our data shows that NMR spectroscopy of cell-material interactions may reveal metabolic effects of organic test substances which are not detectable by standard in vitro assays. The comonomer TEGDMA affected the metabolism of the cells on different levels, while HMBP accumulated in the lipid fraction and induced significantly fewer effects on cell metabolism.