Optimization of 2-piperidin-4-yl-acetamides as melanin-concentrating hormone receptor 1 (MCH-R1) antagonists: Designing out hERG inhibition

Herein, we disclose the discovery and optimization of 2-piperidin-4-yl-acetamide derivatives as MCH-R1 antagonists. Structural investigation of piperidin-4-yl-amide and piperidin-4-yl-ureas identified 2-piperidin-4-yl-acetamide-based MCH-R1 antagonists with outstanding in vivo efficacy but flawed with high affinity towards the hERG potassium channel. While existing hERG SAR information was employed to discover highly potent MCH-R1 antagonists with minimized hERG inhibition, additional hurdles prevented their subsequent clinical exploration.     

Plasma FA composition in familial LCAT deficiency indicates SOAT2-derived cholesteryl ester formation in humans

Mutations in the LCAT gene cause familial LCAT deficiency (Online Mendelian Inheritance in Man ID: #245900), a very rare metabolic disorder. LCAT is the only enzyme able to esterify cholesterol in plasma, whereas sterol O-acyltransferases 1 and 2 are the enzymes esterifying cellular cholesterol in cells. Despite the complete lack of LCAT activity, patients with familial LCAT deficiency exhibit circulating cholesteryl esters (CEs) in apoB-containing lipoproteins. To analyze the origin of these CEs, we investigated 24 carriers of LCAT deficiency in this observational study. We found that CE plasma levels were significantly reduced and highly variable among carriers of two mutant LCAT alleles (22.5 [4.0–37.8] mg/dl) and slightly reduced in heterozygotes (218 [153–234] mg/dl). FA distribution in CE (CEFA) was evaluated in whole plasma and VLDL in a subgroup of the enrolled subjects. We found enrichment of C16:0, C18:0, and C18:1 species and a depletion in C18:2 and C20:4 species in the plasma of carriers of two mutant LCAT alleles. No changes were observed in heterozygotes. Furthermore, plasma triglyceride-FA distribution was remarkably similar between carriers of LCAT deficiency and controls. CEFA distribution in VLDL essentially recapitulated that of plasma, being mainly enriched in C16:0 and C18:1, while depleted in C18:2 and C20:4. Finally, after fat loading, chylomicrons of carriers of two mutant LCAT alleles showed CEs containing mainly saturated FAs. This study of CEFA composition in a large cohort of carriers of LCAT deficiency shows that in the absence of LCAT-derived CEs, CEs present in apoB-containing lipoproteins are derived from hepatic and intestinal sterol O-acyltransferase 2.     

Cytogenetic study of a cell line of human penile cancer

A cell line of penile cancer from a 60-year-old Ugandan black patient has been studied by the authors. Transmission and scanning electron microscopy showed a large number of blebs and microvilli at cell surface; desmosomes were evident at TEM. Cytogenetic investigation (R-, C-, Nor-banding) showed the frequent presence of some markers: del(1p),del(1q),iso(3q),der(4),del(8p),11q+, t rob(13;14), 14p+, t rob(21;21). The epidemiology, geographical distribution, and aetiological role of human papilloma virus type 16 and herpes simplex type 2 are discussed.     

Pathogenicity of some chrysosporium species isolated in France

In order to appreciate the pathogenicity of several geophilic Chrysosporium species (including Anixiopsis stercoraria, Chrysosporium keratinophilum, C. tropicum, C. pannorum, C. state of Arthroderma curreyi, C. state of A. multifidum, and C. state of A. tuberculatum), the authors have realized two series of experimental infestations. Inoculation of these fungi on the back of guinea pigs produced rare erythematous scaling lesions which spontaneously disappeared 3–5 weeks later. No real hair invasion was observed. In white mice, eight weeks after intraperitoneal inoculation, granulomas with necrotic center were observed in the peritoneal tissue with C. keratinophilum, C. tropicum, C. state of A. curreyi and C. state of A. tuberculatum. Conidia were often intact in necrotic centers and retrocultures were positive. With C. state of A. curreyi, spherical spores associated with rare budding cells were noted. The pathogenic role of these keratinophilic fungi is uncertain. However, their ability to remain viable for several weeks in skin and peritoneal tissue indicates that they could become pathogen in certain circumstances.This paper was presented at the X^th congress of the International Society for Human and Animal Mycology at Barcelona, Spain from June 27 to July 1, 1988.     

Immunophenotyping of acute myeloid leukaemia: relevance of analysing different lineage-associated markers

The immunophenotype of 135 previously untreated patients with FAB defined acute myeloid leukaemia (AML) was studied at diagnosis. The panel of reagents included monoclonal antibodies (MoAb) recognising myeloid-associated determinants (CD11, CD13, CD14, CD33 and others) as well as MoAb directed towards lymphoid antigens (CD7, CD10, CD19) and TdT. The results indicate that CD13 and/or CD33 are consistently expressed in AML and only rarely in ALL blasts (131/135 + ve cases, versus 4/130 in ALL). Lymphoid antigen expression was rarely detected when CD10 and CD19 were investigated in AML (0.9% and 2% + ve cases, respectively), whereas significant positivities were found for TdT and CD7 (20% and 10% respectively). Concerning FAB subtypes, two new MoAb (LAM3 and LAM7) proved very useful in the specific recognition of AML with monocytic features. The phenotype CD13+ and/or CD33+, CD9+, HLA-DR- was found to be almost exclusive for M3 AML. The response to induction chemotherapy was analysed in CD7+ and in TdT+ patients. In the latter group a statistically significant lower response rate was found with respect to TdT-ve-AML patients.     

Modulation of the cell-mediated immune function by interferon α, β or γ can partially reverse the immunosuppression induced by human T-cell leukemia virus I in human cord blood cultures

Summary Infection with human T-cell leukemia virus type I (HTLV-I) is associated in vitro and in vivo with a remarkable depression of cell-mediated immune functions. In the present report it is shown that early events following virus-induced suppression of the cell-mediated immune response of freshly isolated cord blood mononuclear cells (CBL) infected with HTLV-I can be partially counteracted by treatment with interferons , or (IFN). All three types of IFN exerted a protective effect on CBL cultures exposed to the virus. This resulted in: (a) a reduced number of virus-positive cells until 4 weeks of culture; (b) delay in the clonal expansion of infected cells (IFN and ); (c) increased natural killer cell activity of CBL, 1 week post-infection (p.i.), mediated by IFN; (d) increase of allospecific recognition of infecting and priming HTLV-I donor MT-2 cells by CBL in a cytotoxic-T-lymphocyte-like response, mediated by IFN and particularly by IFN; (e) phenotype distribution of CBL subpopulations, tested 4 days p.i., more similar to that of non-infected CBL cultures.In contrast, the overall CBL proliferation, that is profoundly depressed during the first week p.i., was not restored by IFN treatments, suggesting that boosting of the cell-mediated killing induced by IFN might involve the maturation of undifferentiated precursor cells rather than stimulation of their proliferation. The improvement of the efficiency of the antiviral immune response induced by treatment with IFN is likely to contribute to the clearance of virus-positive cells during the early phase of infection. This would provide experimental evidence to support an immunopharmacological approach contributing to the conversion of HTLV-I carriers from positive to negative.     

Assessment of the mutagenicity of fractions from s-triazine-treated Zea mays

A water-soluble extract from maize plants exposed to 3 s-triazine herbicides (atrazine, simazine and cyanazine) has been shown to be mutagenic in strain TA100 of Salmonella. No mutagenic activity was observed in any control plant extracts using either water or a variety of organic solvents. Gel permeation studies of the extracts suggest that the mutagen(s) are small molecules (less than 1000 MW). HPLC fractionation suggests that the mutagens formed from each of the 3 herbicides are similar in polarity and water solubility, eluting in a 50/50 water:methanol fraction. Approximately 89% of 14C-labeled HPLC chromatographable metabolites of atrazine were also associated with this fraction, suggesting a close chemical link between a labeled but unidentified metabolite and the mutagenic activity.     

Protein synthetic activity and adenylate energy charge in Rhein-treated cultured human glioma cells.

The effect of Rhein (RH) on the protein synthetic activity and adenylate energy charge in human glioma cells cultured in vitro has been investigated. The results demonstrate that in RH-treated cells, the protein synthesis is strongly decreased, but no modifications in the qualitative pattern occur. The extent of inhibition is a function of the drug concentration as well as of the time of exposure. Such an inhibition must be ascribed mainly to a reduction of adenylate energy charge brought about by RH because of its effect on respiration and glycolysis. The correlation between the adenylate energy charge and cell viability, as well as the possibility of using rhein as a biochemical modulator to reduce or to reverse multidrug resistance, are also discussed.