scholarly journals Telithromycin Is Active against Mycobacterium avium in Mice despite Lacking Significant Activity in Standard In Vitro and Macrophage Assays and Is Associated with Low Frequency of Resistance during Treatment

2001 ◽  
Vol 45 (8) ◽  
pp. 2210-2214 ◽  
Author(s):  
Luiz E. Bermudez ◽  
Clark B. Inderlied ◽  
Peter Kolonoski ◽  
Martin Wu ◽  
Priscilla Aralar ◽  
...  

ABSTRACT The activity of telithromycin, a new ketolide, was evaluated in vitro and in vivo against Mycobacterium avium complex (MAC) strains. The MIC of telithromycin for several M. aviumisolates obtained from the blood of AIDS patients ranged from 16 to >128 μg/ml (MIC at which 90% of isolates are inhibited, >128 μg/ml), and the compound did show activity in the macrophage system at concentrations greater than 8 or 16 μg/ml, but this was dependent on the MAC strain used. Telithromycin was then administered to mice infected with MAC strain 101 for 4 weeks at doses of 100, 200, or 400 mg/kg of body weight/day. Treatment with 100 and 200 mg/kg/day was bacteriostatic, but at 400 mg/kg/day telithromycin was bactericidal for MAC strains. The frequency of the emergence of resistance to telithromycin was low despite prolonged usage (12 weeks). This study demonstrates that telithromycin is active in vivo against MAC and warrants further evaluation.

2007 ◽  
Vol 51 (5) ◽  
pp. 1666-1670 ◽  
Author(s):  
Luiz E. Bermudez ◽  
Nima Motamedi ◽  
Christopher Chee ◽  
Gyulnar Baimukanova ◽  
Peter Kolonoski ◽  
...  

ABSTRACT Infection caused by Mycobacterium avium complex (MAC) is common in patients with immunosuppression, such as AIDS, and deficiencies of gamma interferon and interleukin-12, as well as patients with chronic lung diseases. Treatment of MAC disease is limited since few drugs show in vivo activity. We tested a new bridged bicyclic macrolide, EDP-420, against MAC in vitro and in beige mice. EDP-420 was inhibitory in vitro at a concentration ranging from 2 to 8 μg/ml (MIC50 of 4 μg/ml and MIC90 of 8 μg/ml). In macrophages, EDP-420 was inhibitory at 0.5 μg/ml, suggesting that the drug concentrates intracellularly. Mice infected with macrolide-susceptible MAC strain 101 were given 100 mg of EDP-420/kg of body weight daily for 4 weeks and showed a significant reduction in the number of bacteria in both liver and spleen which was greater than the reduction observed with clarithromycin treatment at the same dose (P < 0.05). However, macrolide-resistant MAC 101 did not respond to EDP-420 treatment. A combination of EDP-420 with mefloquine was shown to be indifferent; mefloquine alone was active against macrolide-resistant MAC. The frequency of resistance to EDP-420 in MAC 101 was 10−9, which is significantly less than the emergence of resistance to clarithromycin, ∼10−7 (P < 0.05). Further evaluation of EDP-420 in the treatment of MAC disease is warranted.


2007 ◽  
Vol 2 (1) ◽  
pp. 22
Author(s):  
Enok Sobariah ◽  
Ali Khomsan ◽  
Ingrid S. Surono

<p class="MsoNormal" style="margin: 0cm 12.45pt 6pt 17.85pt; text-align: justify;"><span style="font-size: 10pt;" lang="en-us" xml:lang="en-us">The aim of this study were  to identify the in-vitro tolerance of pro-biotic bacteria to acid and bile salt condition; and  to prove a hypothesis that the supplementation of oxygenated water has a positive effect on the body weight of rat and on viability of pro-biotic bacteria.  The first study was carried out at PAU Laboratory of Bogor Agricultural University, while the second study was conducted at Department of Community Nutrition of Bogor Agricultural University and Microbiology Laboratory of Indonesia Institute of Technology. Forty five rats aged 6 weeks were divided into three groups, i.e., control group without probiotic (a0), Lactobacillus casei Shirota (a1), and Lactobacillus IS-7257 (a2).  Each group (consisting of 5 rats each) has three different treatments, namely, control without oxygenated water (b0), 50 ppm oxygenated water (b2), and 80 ppm oxygenated water (b2). Oxygenated water was administered to the rats twice a day in the morning (3.25 ml) and afternoon (3.00 ml). Observation was carried out on the body  weight of the rats, fecal lactic acid bacteria, coliform, and anaerob bacteria by plate counting, for 4 periods, i.e, prior to the treatment (C0), after three-day treatment (C1), after seven-day treatment (C2), and on the 10<sup>th</sup> day treatment or three days after washed out period. The results indicated that probiotic bacteria are resistant to acid and bile acid condition. Oxygen concentration in water has a significant positive influence on the body weight of rats towards viability of probiotic bacteria (p-level &lt; 0.05).  The supplementation of  oxygenated water 50 ppm significantly increase the population of viable fecal lactic acid bacteria in L. casei Shirota and Lactobacillus IS-7257 groups after 3 and 7 days of treatment.  Lactobacillus IS-7257 gave better response than L. casei Shirota. The supplementation of oxygenated water 80 ppm significantly reduces the fecal coliform in-vivo in both L. casei Shirota and Lactobacillus IS-7257 groups (p-level &lt; 0.05).</span></p>


1994 ◽  
Vol 28 (11) ◽  
pp. 1250-1254 ◽  
Author(s):  
Daniel S. Maddix ◽  
Kimberly B. Tallian ◽  
Paul S. Mead

OBJECTIVE: To discuss the mechanism of action, in vitro and in vivo activity, pharmacokinetics, clinical trials, adverse effects, drug interactions, and dosage guidelines of rifabutin. DATA SOURCES: Pertinent literature published between 1982 and 1993 was identified via a MEDLINE search. Published proceedings of selected conferences were also reviewed. STUDY SELECTION: Selected basic science, microbiologic, and pharmacokinetic articles were evaluated. Because only limited data regarding rifabutin were available in the literature, all clinical trials involving the use of rifabutin in the prevention of Mycobacterium avium complex (MAC) infection in AIDS patients were reviewed. DATA SYNTHESIS: Rifabutin is a rifamycin derivative that was approved recently for the prevention of disseminated MAC disease in patients with advanced HIV infection. The drug has in vitro and in vivo activity against gram-positive bacteria, gram-negative bacteria, and mycobacteria. Two prospective, randomized, double-blind, placebo-controlled, multicenter trials demonstrated that rifabutin decreased the progression to MAC bacteremia in AIDS patients by about 50 percent. Adverse effects that resulted in the discontinuation of rifabutin prophylaxis occurred in 16 percent of patients. Rifabutin induces hepatic enzymes to a lesser extent than does rifampin, but dosage adjustment of drugs that are known to interact with rifampin may be required. CONCLUSIONS: Rifabutin is the only drug shown to be effective in the prevention of MAC bacteremia in AIDS patients; therefore, it should be made available as a formulary agent. It may be reasonable to delay initiation of rifabutin prophylaxis until CD4 lymphocyte counts are less than 75–50/mm3.


2010 ◽  
Vol 54 (10) ◽  
pp. 4471-4473 ◽  
Author(s):  
Henry S. Heine ◽  
Jennifer Bassett ◽  
Lynda Miller ◽  
Bret K. Purcell ◽  
W. Russell Byrne

ABSTRACT Daptomycin demonstrated in vitro (MIC90, 4 μg/ml) and in vivo activities against Bacillus anthracis. Twice-daily treatment with a dose of 50 mg/kg of body weight was begun 24 h after challenge and continued for 14 or 21 days; results were compared to those for controls treated with phosphate-buffered saline or ciprofloxacin. Day 43 survival rates were 6/10 mice for the 14-day and 9/10 mice for the 21-day treatment groups, compared to survival with ciprofloxacin: 8/10 and 9/10 mice, respectively. Culture results from tissues removed at the termination of the experiment were negative.


2000 ◽  
Vol 44 (10) ◽  
pp. 2895-2896 ◽  
Author(s):  
M. H. Cynamon ◽  
J. L. Carter ◽  
C. M. Shoen

ABSTRACT ABT-773, a new ketolide antimicrobial agent, was evaluated in comparison to clarithromycin (CLA) in vitro against Mycobacterium avium complex (MAC) and in a beige mouse model of disseminated MAC infection. The MICs at which 50 and 90% of the isolates tested were inhibited were 2 and 4 μg/ml, respectively, for CLA and 8 and 16 μg/ml, respectively, for ABT-773. Eight CLA-resistant isolates were found to be resistant to ABT-773 (MICs > 64 μg/ml). In the in vivo study mice were treated with ABT-773 (50, 100, and 200 mg/kg of body weight) or CLA (200 mg/kg). Both ABT-773 (100 and 200 mg/kg) and CLA significantly decreased the viable cell counts in spleens and lungs. ABT-773 (200 mg/kg) and CLA had similar activities in lungs, but the former was more active in spleens.


2021 ◽  
Vol 7 (6) ◽  
pp. 439
Author(s):  
Tecla Ciociola ◽  
Walter Magliani ◽  
Tiziano De Simone ◽  
Thelma A. Pertinhez ◽  
Stefania Conti ◽  
...  

It has been previously demonstrated that synthetic antibody-derived peptides could exert a significant activity in vitro, ex vivo, and/or in vivo against microorganisms and viruses, as well as immunomodulatory effects through the activation of immune cells. Based on the sequence of previously described antibody-derived peptides with recognized antifungal activity, an in silico analysis was conducted to identify novel antifungal candidates. The present study analyzed the candidacidal and structural properties of in silico designed peptides (ISDPs) derived by amino acid substitutions of the parent peptide KKVTMTCSAS. ISDPs proved to be more active in vitro than the parent peptide and all proved to be therapeutic in Galleria mellonella candidal infection, without showing toxic effects on mammalian cells. ISDPs were studied by circular dichroism spectroscopy, demonstrating different structural organization. These results allowed to validate a consensus sequence for the parent peptide KKVTMTCSAS that may be useful in the development of novel antimicrobial molecules.


2020 ◽  
Vol 54 (01) ◽  
pp. 37-46
Author(s):  
Kristina Friedland ◽  
Giacomo Silani ◽  
Anita Schuwald ◽  
Carola Stockburger ◽  
Egon Koch ◽  
...  

Abstract Background Silexan, a special essential oil from flowering tops of lavandula angustifolia, is used to treat subsyndromal anxiety disorders. In a recent clinical trial, Silexan also showed antidepressant effects in patients suffering from mixed anxiety-depression (ICD-10 F41.2). Since preclinical data explaining antidepressant properties of Silexan are missing, we decided to investigate if Silexan also shows antidepressant-like effects in vitro as well as in vivo models. Methods We used the forced swimming test (FST) in rats as a simple behavioral test indicative of antidepressant activity in vivo. As environmental events and other risk factors contribute to depression through converging molecular and cellular mechanisms that disrupt neuronal function and morphology—resulting in dysfunction of the circuitry that is essential for mood regulation and cognitive function—we investigated the neurotrophic properties of Silexan in neuronal cell lines and primary hippocampal neurons. Results The antidepressant activity of Silexan (30 mg/kg BW) in the FST was comparable to the tricyclic antidepressant imipramine (20 mg/kg BW) after 9-day treatment. Silexan triggered neurite outgrowth and synaptogenesis in 2 different neuronal cell models and led to a significant increase in synaptogenesis in primary hippocampal neurons. Silexan led to a significant phosphorylation of protein kinase A and subsequent CREB phosphorylation. Conclusion Taken together, Silexan demonstrates antidepressant-like effects in cellular as well as animal models for antidepressant activity. Therefore, our data provides preclinical evidence for the clinical antidepressant effects of Silexan in patients with mixed depression and anxiety.


Molecules ◽  
2021 ◽  
Vol 26 (2) ◽  
pp. 331
Author(s):  
Jung-Yun Lee ◽  
Tae Yang Kim ◽  
Hanna Kang ◽  
Jungbae Oh ◽  
Joo Woong Park ◽  
...  

Excess body weight is a major risk factor for type 2 diabetes (T2D) and associated metabolic complications, and weight loss has been shown to improve glycemic control and decrease morbidity and mortality in T2D patients. Weight-loss strategies using dietary interventions produce a significant decrease in diabetes-related metabolic disturbance. We have previously reported that the supplementation of low molecular chitosan oligosaccharide (GO2KA1) significantly inhibited blood glucose levels in both animals and humans. However, the effect of GO2KA1 on obesity still remains unclear. The aim of the study was to evaluate the anti-obesity effect of GO2KA1 on lipid accumulation and adipogenic gene expression using 3T3-L1 adipocytes in vitro and plasma lipid profiles using a Sprague-Dawley (SD) rat model. Murine 3T3-L1 preadipocytes were stimulated to differentiate under the adipogenic stimulation in the presence and absence of varying concentrations of GO2KA1. Adipocyte differentiation was confirmed by Oil Red O staining of lipids and the expression of adipogenic gene expression. Compared to control group, the cells treated with GO2KA1 significantly decreased in intracellular lipid accumulation with concomitant decreases in the expression of key transcription factors, peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer-binding protein alpha (CEBP/α). Consistently, the mRNA expression of downstream adipogenic target genes such as fatty acid binding protein 4 (FABP4), fatty acid synthase (FAS), were significantly lower in the GO2KA1-treated group than in the control group. In vivo, male SD rats were fed a high fat diet (HFD) for 6 weeks to induced obesity, followed by oral administration of GO2KA1 at 0.1 g/kg/body weight or vehicle control in HFD. We assessed body weight, food intake, plasma lipids, levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) for liver function, and serum level of adiponectin, a marker for obesity-mediated metabolic syndrome. Compared to control group GO2KA1 significantly suppressed body weight gain (185.8 ± 8.8 g vs. 211.6 ± 20.1 g, p < 0.05) with no significant difference in food intake. The serum total cholesterol, triglyceride, and low-density lipoprotein (LDL) levels were significantly lower in the GO2KA1-treated group than in the control group, whereas the high-density lipoprotein (HDL) level was higher in the GO2KA1 group. The GO2KA1-treated group also showed a significant reduction in ALT and AST levels compared to the control. Moreover, serum adiponectin levels were significantly 1.5-folder higher than the control group. These in vivo and in vitro findings suggest that dietary supplementation of GO2KA1 may prevent diet-induced weight gain and the anti-obesity effect is mediated in part by inhibiting adipogenesis and increasing adiponectin level.


1996 ◽  
Vol 40 (11) ◽  
pp. 2567-2572 ◽  
Author(s):  
J R Sufrin ◽  
D Rattendi ◽  
A J Spiess ◽  
S Lane ◽  
C J Marasco ◽  
...  

Fifteen purine nucleosides and their O-acetylated ester derivatives were examined for in vitro antitrypanosomal activity against the LAB 110 EATRO isolate of Trypanosoma brucei brucei and two clinical isolates of Trypanosoma brucei rhodesiense. Initial comparisons of activity were made for the LAB 110 EATRO isolate. Three nucleoside analogs exhibited no significant activity (50% inhibitory concentrations [IC50s] of > 100 microM), whether they were O acetylated or unacetylated; three nucleosides showed almost equal activity (IC50s of < 5 microM) for the parent compound and the O-acetylated derivative; nine nucleosides showed significantly improved activity (> or = 3-fold) upon O acetylation; of these nine analogs, six displayed activity at least 10-fold greater than that of their parent nucleosides. The most significant results were those for four apparently inactive compounds which, upon O acetylation, displayed IC50s of < or = 25 microM. When the series of compounds was tested against T. brucei rhodesiense isolates (KETRI 243 and KETRI 269), their antitrypanosomal effects were comparable to those observed for the EATRO 110 strain. Thus, our studies of purine nucleosides have determined that O acetylation consistently improved their in vitro antitrypanosomal activity. This observed phenomenon was independent of their cellular enzyme targets (i.e., S-adenosylmethionine, polyamine, or purine salvage pathways). On the basis of our results, the routine preparation of O-acetylated purine nucleosides for in vitro screening of antitrypanosomal activity is recommended, since O acetylation transformed several inactive nucleosides into compounds with significant activity, presumably by improving uptake characteristics. O-acetylated purine nucleosides may offer in vivo therapeutic advantages compared with their parent nucleosides, and this possibility should be considered in future evaluations of this structural class of trypanocides.


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