Chagas' disease, a protozoan infection by the kinetoplastid Trypanosoma cruzi, constitutes a major public health problem in Latin America. With the use of mouse models of both short- and long-term forms of the disease, the efficacy of D0870, a bis-triazole derivative, was tested. D0870 was able to prevent death and induced parasitological cure in 70 to 90 percent of animals, in both the short- and long-term disease. In contrast, currently used drugs such as nifurtimox or ketoconazole prolonged survival but did not induce significant curing effects. D0870 may be useful in the treatment of human long-term Chagas' disease, a condition that is currently incurable.
ObjectiveTo retrospectively investigate safety and efficacy of nusinersen in a large cohort of adult Italian patients with spinal muscular atrophy (SMA).MethodsInclusion criteria were: (1) clinical and molecular diagnosis of SMA2 or SMA3; (2) nusinersen treatment started in adult age (>18 years); (3) clinical data available at least at baseline (T0-beginning of treatment) and 6 months (T6).ResultsWe included 116 patients (13 SMA2 and 103 SMA3) with median age at first administration of 34 years (range 18–72). The Hammersmith Functional Rating Scale Expanded (HFMSE) in patients with SMA3 increased significantly from baseline to T6 (median change +1 point, p<0.0001), T10 (+2, p<0.0001) and T14 (+3, p<0.0001). HFMSE changes were independently significant in SMA3 sitter and walker subgroups. The Revised Upper Limb Module (RULM) in SMA3 significantly improved between T0 and T14 (median +0.5, p=0.012), with most of the benefit observed in sitters (+2, p=0.018). Conversely, patients with SMA2 had no significant changes of median HFMSE and RULM between T0 and the following time points, although a trend for improvement of RULM was observed in those with some residual baseline function. The rate of patients showing clinically meaningful improvements (as defined during clinical trials) increased from 53% to 69% from T6 to T14.ConclusionsOur data provide further evidence of nusinersen safety and efficacy in adult SMA2 and SMA3, with the latter appearing to be cumulative over time. In patients with extremely advanced disease, effects on residual motor function are less clear.
Identifying the genes that influence levels of pro-inflammatory molecules can help to elucidate the mechanisms underlying this process. We first conducted a two-stage genome-wide association scan (GWAS) for the key inflammatory biomarkers Interleukin-6 (IL-6), the general measure of inflammation erythrocyte sedimentation rate (ESR), monocyte chemotactic protein-1 (MCP-1), and high-sensitivity C-reactive protein (hsCRP) in a large cohort of individuals from the founder population of Sardinia. By analysing 731,213 autosomal or X chromosome SNPs and an additional ∼1.9 million imputed variants in 4,694 individuals, we identified several SNPs associated with the selected quantitative trait loci (QTLs) and replicated all the top signals in an independent sample of 1,392 individuals from the same population. Next, to increase power to detect and resolve associations, we further genotyped the whole cohort (6,145 individuals) for 293,875 variants included on the ImmunoChip and MetaboChip custom arrays. Overall, our combined approach led to the identification of 9 genome-wide significant novel independent signals—5 of which were identified only with the custom arrays—and provided confirmatory evidence for an additional 7. Novel signals include: for IL-6, in the ABO gene (rs657152, p = 2.13×10−29); for ESR, at the HBB (rs4910472, p = 2.31×10−11) and UCN119B/SPPL3 (rs11829037, p = 8.91×10−10) loci; for MCP-1, near its receptor CCR2 (rs17141006, p = 7.53×10−13) and in CADM3 (rs3026968, p = 7.63×10−13); for hsCRP, within the CRP gene (rs3093077, p = 5.73×10−21), near DARC (rs3845624, p = 1.43×10−10), UNC119B/SPPL3 (rs11829037, p = 1.50×10−14), and ICOSLG/AIRE (rs113459440, p = 1.54×10−08) loci. Confirmatory evidence was found for IL-6 in the IL-6R gene (rs4129267); for ESR at CR1 (rs12567990) and TMEM57 (rs10903129); for MCP-1 at DARC (rs12075); and for hsCRP at CRP (rs1205), HNF1A (rs225918), and APOC-I (rs4420638). Our results improve the current knowledge of genetic variants underlying inflammation and provide novel clues for the understanding of the molecular mechanisms regulating this complex process.
We have investigated the antiproliferative effects of SCH 56592, a new experimental triazole, against Trypanosoma (Schizotrypanum) cruzi, the etiological agent of Chagas' disease in Latin America. SCH 56592 blocked the proliferation of the epimastigote form of the parasite in vitro at 30 nM, a concentration 30-to 100-fold lower than that required with the reference compounds ketoconazole and itraconazole. At that concentration all the parasite's endogenous sterols (ergosterol, 24-ethyl-cholesta-5,7,22-trien-3-ol, and its 22-dihydro analogs), were replaced by methylated sterols (lanosterol and 24-methylene-dihydrolanosterol), as revealed by high-resolution gas chromatography coupled with mass spectrometry. This indicated that the primary mechanism of action of the drug was inhibition of the parasite's sterol C-14␣ demethylase. Against the clinically relevant intracellular amastigote form, grown in cultured Vero cells at 37°C, the MIC of SCH 56592 was 0.3 nM, again 33-to 100-fold lower than that of ketoconazole or itraconazole. In a murine model of acute Chagas' disease, SCH 56592 given at > 10 mg/kg of body weight/day for a total of 43 doses allowed 85 to 100% survival and 90 to 100% cure of the surviving animals, as verified by parasitological, serological, and PCRbased tests, while ketoconazole given at 30 mg/kg day allowed 60% survival but only 20% cure. In a murine model of chronic Chagas' disease, SCH 56592 was again more effective than ketoconazole, providing 75 to 85% protection from death, with 60 to 75% parasitological cures of the surviving animals, while no parasitological cures were observed with ketoconazole. The results indicate that SCH 56592 is the most powerful sterol biosynthesis inhibitor ever tested against T. cruzi and may be useful in the treatment of human Chagas' disease.
We have studied the antiproliferative effects of mevinolin (lovastatin), an inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, on the protozoan parasite Trypanosoma (Schizotrypanum) cruzi and its ability to potentiate the action of specific ergosterol biosynthesis inhibitors, such as ketoconazole and terbinafine, both in vitro and in vivo. Against the epimastigote form in vitro, mevinolin produced a dose-dependent reduction of the growth rate up to 25 ,uM, but at 50 and 75 ,uM, complete growth arrest and cell lysis took place after 144 and 96 h, respectively. A systematic study of the effects of mevinolin combined with ketoconazole and terbinafine, which act at different points in the ergosterol biosynthesis pathway, on the proliferation of epimastigotes indicated a synergic action, as shown by concave isobolograms and fractional inhibitory concentration indexes ranging from 0.17 to 0.54. Analysis of the sterol composition and de novo sterol synthesis in control and treated cells by thin-layer and gas-liquid chromatographies showed that the antiproliferative effects of the drug alone and in combination were correlated with the depletion of the endogenous ergosterol pool and particularly with a critical (exogenous) cholesterol/endogenous 4-desmethyl sterol ratio in the cells. When we studied the effects of mevinolin on the amastigote form proliferating inside Vero cells in vitro, only very modest effects on the parasites were observed up to 0.75 ,M; above this concentration, significant deleterious effects on the host cells were found. However, when the same concentration of the drug was combined with ketoconazole, it was able to reduce by a factor of 10 the concentration of the azole required to eradicate the parasite (from 10 to 1 nM), again indicating a synergic action. On the other hand, a combination of mevinolin and terbinafine had only additive effects on amastigotes, but a ternary combination of mevinolin, ketoconazole, and terbinafine was again clearly synergistic. In vivo studies with a murine model of Chagas' disease showed that mevinolin can also potentiate the therapeutic effects of ketoconazole in this system; combined treatment with the two drugs at doses that alone offered only limited protection against the parasite was able to essentially eliminate circulating parasites and produce complete protection against death. These results confirm the synergic action against the proliferative stages of T. cruzi both in vitro and in vivo of combined ergosterol biosynthesis inhibitors that act at different points in the pathway and suggest that mevinolin combined with azoles, such as ketoconazole, can be used in the treatment of human Chagas' disease.
We have studied the antiproliferative effects of two sterol analogs previously reported as potent inhibitors of Δ24(25) sterol methyl transferase (E.C. 2.1.1.43) of yeasts and fungi on epimastigotes and amastigotes on Trypanosoma (Schizotrypanum) cruzi, the causative agents of Chagas disease, as well as its chemotherapeutic effecs in a murine model of the disease. On the epimastigote form proliferating in liver infusion tryptose medium at 28 C 22,26-azasterol (AZA), a cholestanol analog with a 6-membered aza ring as a side chain produced a dose-dependent reduction of the growth rate up to 3 µM, but at 10 µM complete growth arest and cell lysis took place after 120-144 h. For 24(R, S), 25-epiminolanosterol (EIL), complete growth arrest and lysis took place with 6 µM. In both cases the antiproliferative effects were potentiated by the simultaneous incubation of the epimastigotes with inhibitors of sterol C-14α-demethylase such as ketoconazole or SDZ 89,485, as indicated by concave isobolograms and fractional inhibitory concentrations ranging from 0.11 to 0.46. Analysis of the sterol composition in control and treated cells by thin-layer and capillary gas-liquid chromatography coupled to mass spectrometry showed that growth inhibition correlated with the complete disappearance of the native endogenous sterols of the parasite (ergosterol and 24-ethyl analogs) and the accumulation of 24-desalkyl sterols. Against the clinically relevant amastigote form proliferating inside cultured Vera cells at 37°C, AZA eradicated the parasite of 100 nM, while the corresponding concentration for EIL was 300 nM. Synergic effects of both inhibitors when combined with ketoconazole against this form of the parasite was demonstrated using a three-dimensional analytic method which allowed the identification of optimal drug concentrations. Finally, it was found that daily oral administration of AZA at 50 mg/kg/day for a total of 43 doses to mice infected with a lethal inoculum of T. cruzi allowed survival of all treated animals 25 days after infection, while all control (untreated) animals were dead at this point of time. Increased survival correlated with a 90% reduction in parasitemia in the treated animals. The antiparasitic effects of the azasterol were potentiated in combined treatments with ketoconazole. This is the first report of a successful application of a sterol methyl transferase inhibitor as a chemotherapeutic agent in a protozoal infection.
Both the glucose 6-phosphate independent (I) and the glucose 6-phosphate dependent (D) forms of rat muscle glycogen synthetase are inhibited by adenosine triphosphate (ATP), adenosine diphosphate (ADP), and P¡. The inhibition is, kinetically, of the competitive type with respect to uridine diphosphate glucose (UDP-glucose). Glucose 6-phosphate reverses this inhibition, without affecting, at pH 6.6, the Km for UDP-glucose. UDP, one of the reaction products, is a strong inhibitor and its effect is not reversed by glucose 6-phosphate. Photooxidation of the I form in the presence of methylene blue causes a preferential loss of the inhibition by ATP, as compared to that by UDP. The sum of this evidence suggests that UDP-
We have investigated the growth-inhibitory effects of two ergosterol biosynthesis inhibitors, the dioxolane imidazole ketoconazole and the allylamine SF 86-327, alone and in combination, on the proliferative stages of Trypanosoma (Schizotrypanum) cruzi, the causative agent of Chagas' disease. Proliferation of epimastigotes in liver infusion-tryptose medium at 28 degrees C was immediately arrested by any of these drugs at greater than or equal to 3 x 10(-5) M; cell lysis occurred 24 h later. Below that concentration, SF 86-327 at concentrations down to 1 x 10(-6) M stopped growth after 48 h. In contrast, ketoconazole slowed cell growth only moderately, but proliferation finally stopped and cell lysis occurred after 120 h at 3 x 10(-6) M. Synergistic effects could be observed when the two drugs were used in combination: the concentration of SF 86-327 required to reduce the cell growth to 25% of controls in 144 h was reduced 33-fold in the presence of 1 x 10(-6) M ketoconazole, which by itself reduced growth only by 30%. Amastigotes, proliferating in Vero cells at 37 degrees C, were much more susceptible to both drugs, but ketoconazole was definitely a more potent antiparasitic agent than the allylamine in this system: whereas the concentration of SF 86-327 required to reduce the number of infected cells to 50% of controls was 1 x 10(-7) M and that required to completely eradicate the parasite was 3 x 10(-6) M, for ketoconazole these concentrations were 1 x 10(-10) M and 1 x 10(-8) M, respectively. Again, strong synergistic effects were observed when the drugs were used in combination: the concentration of SF 86-327 required to reduce the number of infected cells to 50% of controls was 100-fold lower in the presence of 10(-11) M ketoconazole, which by itself had no effects on amastigote proliferation. The parasite was completely eradicated when the drugs were used in combination at concentrations as low as 10(-9) M. Synergy of the antiproliferative effects of the drugs on both froms of the parasite was further demonstrated by concave isobolograms. On the other hand, SF 86-327 at 10(-5) M had no effects on the proliferation of Vero cells, whereas ketoconazole at 10(-7) M reduced the proliferation of these cells by 50%.
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