1
|
Dow CT. Warm, Sweetened Milk at the Twilight of Immunity - Alzheimer's Disease - Inflammaging, Insulin Resistance, M. paratuberculosis and Immunosenescence. Front Immunol 2021; 12:714179. [PMID: 34421917 PMCID: PMC8375433 DOI: 10.3389/fimmu.2021.714179] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 07/09/2021] [Indexed: 01/22/2023] Open
Abstract
This article prosecutes a case against the zoonotic pathogen Mycobacterium avium ss. paratuberculosis (MAP) as a precipitant of Alzheimer’s disease (AD). Like the other major neurodegenerative diseases AD is, at its core, a proteinopathy. Aggregated extracellular amyloid protein plaques and intracellular tau protein tangles are the recognized protein pathologies of AD. Autophagy is the cellular housekeeping process that manages protein quality control and recycling, cellular metabolism, and pathogen elimination. Impaired autophagy and cerebral insulin resistance are invariant features of AD. With a backdrop of age-related low-grade inflammation (inflammaging) and heightened immune risk (immunosenescence), infection with MAP subverts glucose metabolism and further exhausts an already exhausted autophagic capacity. Increasingly, a variety of agents have been found to favorably impact AD; they are agents that promote autophagy and reduce insulin resistance. The potpourri of these therapeutic agents: mTOR inhibitors, SIRT1 activators and vaccines are seemingly random until one recognizes that all these agents also suppress intracellular mycobacterial infection. The zoonotic mycobacterial MAP causes a common fatal enteritis in ruminant animals. Humans are exposed to MAP from contaminated food products and from the environment. The enteritis in animals is called paratuberculosis or Johne’s disease; in humans, it is the putative cause of Crohn’s disease. Beyond Crohn’s, MAP is associated with an increasing number of inflammatory and autoimmune diseases: sarcoidosis, Blau syndrome, autoimmune diabetes, autoimmune thyroiditis, multiple sclerosis, and rheumatoid arthritis. Moreover, MAP has been associated with Parkinson’s disease. India is one county that has extensively studied the human bio-load of MAP; 30% of more than 28,000 tested individuals were found to harbor, or to have harbored, MAP. This article asserts an unfolding realization that MAP infection of humans 1) is widespread in its presence, 2) is wide-ranging in its zoonosis and 3) provides a plausible link connecting MAP to AD.
Collapse
Affiliation(s)
- Coad Thomas Dow
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, United States
| |
Collapse
|
2
|
|
3
|
Juste RA, Elguezabal N, Garrido JM, Pavon A, Geijo MV, Sevilla I, Cabriada JL, Tejada A, García-Campos F, Casado R, Ochotorena I, Izeta A, Greenstein RJ. On the prevalence of M. avium subspecies paratuberculosis DNA in the blood of healthy individuals and patients with inflammatory bowel disease. PLoS One 2008; 3:e2537. [PMID: 18596984 PMCID: PMC2434204 DOI: 10.1371/journal.pone.0002537] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2008] [Accepted: 05/21/2008] [Indexed: 12/13/2022] Open
Abstract
Background Mycobacteria, such as M. leprae and M. tuberculosis infect billions of humans. However, because of appropriate immune responses and antibiotic therapy, overt mycobacterial diseases occur far less frequently. M. avium subspecies paratuberculosis (MAP) causes Johne's disease in ruminants, an affliction evocative of inflammatory bowel disease (IBD). Several agents used to treat IBD (5-ASA, methotrexate, azathioprine and its metabolite 6-MP) have recently been shown to be antiMAP antibiotics. We herein evaluate the prevalence of MAP DNA in healthy individuals and compare them with IBD patients on antiMAP antibiotics. Methods We studied 100 healthy individuals (90 blood donors) and 246 patients with IBD. IS900 MAP DNA was identified using a nested primer PCR in the buffy coat of blood. Positive signal was confirmed as MAP by DNA sequence analysis. PCR positive results frequencies were compared according to medications used. Significance was accepted at p<0.05. Results 47% (47/100) healthy controls and 16% (40/246) IBD patients were IS900 positive (p<0.0001). MAP DNA was identified in 17% of 143 patients receiving mesalamine and 6% of 16 receiving sulfasalazine. None of the IBD patients receiving methotrexate (n = 9), 6-MP (n = 3), ciprofloxacin (n = 5) or Tacrolimus® (n = 3) had MAP DNA detectable in their blood. Discussion We found a disquietingly large percentage of healthy individuals have MAP DNA in their blood, the significance of which remains to be determined. Counter-intuitively, the incidence of MAP DNA was significantly lower in patients with IBD. Agents with the most potent in vitro antiMAP activity were associated with clearance of blood MAP DNA. We posit that the use antiMAP antibiotics was responsible for the decreased prevalence of MAP DNA in patients with IBD.
Collapse
Affiliation(s)
- Ramon A Juste
- Departamento de Producción y Sanidad Animal, Instituto Vasco de Investigación y Desarrollo Agrario (NEIKER-Tecnalia), Derio, Bizkaia, Spain.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
4
|
On the action of cyclosporine A, rapamycin and tacrolimus on M. avium including subspecies paratuberculosis. PLoS One 2008; 3:e2496. [PMID: 18575598 PMCID: PMC2427180 DOI: 10.1371/journal.pone.0002496] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Accepted: 04/22/2008] [Indexed: 12/16/2022] Open
Abstract
Background Mycobacterium avium subspecies paratuberculosis (MAP) may be zoonotic. Recently the “immuno-modulators” methotrexate, azathioprine and 6-MP and the “anti-inflammatory” 5-ASA have been shown to inhibit MAP growth in vitro. We concluded that their most plausible mechanism of action is as antiMAP antibiotics. The “immunosuppressants” Cyclosporine A, Rapamycin and Tacrolimus (FK 506) treat a variety of “autoimmune” and “inflammatory” diseases. Rapamycin and Tacrolimus are macrolides. We hypothesized that their mode of action may simply be to inhibit MAP growth. Methodology The effect on radiometric MAP 14CO2 growth kinetics of Cyclosporine A, Rapamycin and Tacrolimus on MAP cultured from humans (Dominic & UCF 4) or ruminants (ATCC 19698 & 303) and M. avium subspecies avium (ATCC 25291 & 101) are presented as “percent decrease in cumulative GI” (%-ΔcGI.) Principal Findings The positive control clofazimine has 99%-ΔcGI at 0.5 µg/ml (Dominic). Phthalimide, a negative control has no dose dependent inhibition on any strain. Against MAP there is dose dependent inhibition by the immunosuppressants. Cyclosporine has 97%-ΔcGI by 32 µg/ml (Dominic), Rapamycin has 74%-ΔcGI by 64 µg/ml (UCF 4) and Tacrolimus 43%-ΔcGI by 64 µg/ml (UCF 4) Conclusions We show heretofore-undescribed inhibition of MAP growth in vitro by “immunosuppressants;” the cyclic undecapeptide Cyclosporine A, and the macrolides Rapamycin and Tacrolimus. These data are compatible with our thesis that, unknowingly, the medical profession has been treating MAP infections since 1942 when 5-ASA and subsequently azathioprine, 6-MP and methotrexate were introduced in the therapy of some “autoimmune” and “inflammatory” diseases.
Collapse
|
5
|
Philalay JS, Palermo CO, Hauge KA, Rustad TR, Cangelosi GA. Genes required for intrinsic multidrug resistance in Mycobacterium avium. Antimicrob Agents Chemother 2004; 48:3412-8. [PMID: 15328105 PMCID: PMC514743 DOI: 10.1128/aac.48.9.3412-3418.2004] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Genes required for intrinsic multidrug resistance by Mycobacterium avium were identified by screening a library of transposon insertion mutants for the inability to grow in the presence of ciprofloxacin, clarithromycin, and penicillin at subinhibitory concentrations. Two genes, pks12 and Maa2520, were disrupted in multiple drug-susceptible mutants. The pks12 gene (Maa1979), which may be cotranscribed with a downstream gene (Maa1980), is widely conserved in the actinomycetes. Its ortholog in Mycobacterium tuberculosis is a polyketide synthase required for the synthesis of dimycocerosyl phthiocerol, a major cell wall lipid. Mutants of M. avium with insertions into pks12 exhibited altered colony morphology and were drug susceptible, but they grew as well as the wild type did in vitro and intracellularly within THP-1 cells. A pks12 mutant of M. tuberculosis was moderately more susceptible to clarithromycin than was its parent strain; however, susceptibility to ciprofloxacin and penicillin was not altered. M. avium complex (MAC) and M. tuberculosis appear to have different genetic mechanisms for resisting the effects of these antibiotics, with pks12 playing a relatively more significant role in MAC. The second genetic locus identified in this study, Maa2520, is a conserved hypothetical gene with orthologs in M. tuberculosis and Mycobacterium leprae. It is immediately upstream of Maa2521, which may code for an exported protein. Mutants with insertions at this locus were susceptible to multiple antibiotics and slow growing in vitro and were unable to survive intracellularly within THP-1 cells. Like pks12 mutants, they exhibited increased Congo red binding, an indirect indication of cell wall modifications. Maa2520 and pks12 are the first genes to be linked by mutation to intrinsic drug resistance in MAC.
Collapse
Affiliation(s)
- Julie S Philalay
- Seattle Biomedical Research Institute, 4 Nickerson St., Seattle, WA 98109, USA
| | | | | | | | | |
Collapse
|
6
|
Kaur D, Khuller GK. In vitro, ex-vivo and in vivo activities of ethambutol and sparfloxacin alone and in combination against mycobacteria. Int J Antimicrob Agents 2001; 17:51-5. [PMID: 11137649 DOI: 10.1016/s0924-8579(00)00308-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The MIC of ethambutol and sparfloxacin for Mycobacterium smegmatis and M. avium was determined using a broth dilution method. The MICs of sparfloxacin and ethambutol were lower for M. smegmatis than M. avium. The combination of ethambutol and sparfloxacin was additive against M. smegmatis but synergistic for M. avium. The effect of these drugs alone and in combination used at C(max) levels was screened against M. avium and M. tuberculosis H(37)Rv growing intracellularly in murine macrophage cell lines. In vivo studies using this combination given at 100 mg/kg of body weight once weekly showed greater activity than the drugs used singly. These results suggest that combination of ethambutol and sparfloxacin has significant activity intracellularly and in animal models against M. avium and M. tuberculosis.
Collapse
Affiliation(s)
- D Kaur
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research, 160 012, Chandigarh, India
| | | |
Collapse
|
7
|
Rastogi N, Goh KS, Horgen L, Barrow WW. Synergistic activities of antituberculous drugs with cerulenin and trans-cinnamic acid against Mycobacterium tuberculosis. FEMS IMMUNOLOGY AND MEDICAL MICROBIOLOGY 1998; 21:149-57. [PMID: 9685005 DOI: 10.1111/j.1574-695x.1998.tb01161.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The recent upsurge in the incidence of tuberculosis with significant emergence of multidrug-resistant cases has focused on the priority of discovering effective new drugs and on the strategies to augment the potential of existing drugs against Mycobacterium tuberculosis. In the present study, we investigated cerulenin and trans-cinnamic acid, which have recently been shown to augment the activity of various antibiotics against Mycobacterium avium [Antimicrob. Agents Chemother. 38 (1994) 2287-2295], to enhance the activity of isoniazid, rifampin, ofloxacin, amikacin and clofazimine against M. tuberculosis. The synergy observed was compared with identical combinations using ethambutol, a cell wall-inhibiting drug used in standard antituberculous chemotherapy. The results showed that ethambutol resulted in synergistic activity in 12/30 drug combinations, as compared to 15/36 for cerulenin and 101/18 for trans-cinnamic acid. This increase in drug activity was even observed with drug-resistant isolates. Use of novel antimicrobials and understanding of their mechanisms of action may be an effective strategy to determine previously undescribed targets for future drug development.
Collapse
Affiliation(s)
- N Rastogi
- Unité de la Tuberculose et des Mycobactéries, Institut Pasteur, Pointe à Pitre, Guadeloupe.
| | | | | | | |
Collapse
|
8
|
Mdluli K, Swanson J, Fischer E, Lee RE, Barry CE. Mechanisms involved in the intrinsic isoniazid resistance of Mycobacterium avium. Mol Microbiol 1998; 27:1223-33. [PMID: 9570407 DOI: 10.1046/j.1365-2958.1998.00774.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Isoniazid (INH), which acts by inhibiting mycolic acid biosynthesis, is very potent against the tuberculous mycobacteria. It is about 100-fold less effective against Mycobacterium avium. This difference has often been attributed to a decreased permeability of the cell wall. We measured the rate of conversion of radiolabelled INH to 4-pyridylmethanol by whole cells and cell-free extracts and estimated the permeability barrier imposed by the cell wall to INH influx in Mycobacterium tuberculosis and M. avium. There was no significant difference in the relative permeability to INH between these two species. However, the total conversion rate in M. tuberculosis was found to be four times greater. Examination of in vitro-generated mutants revealed that the major resistance mechanism for both species is loss of the catalase-peroxidase KatG. Analysis of lipid and protein biosynthetic profiles demonstrated that the molecular target of activated INH was identical for both species. M. avium, however, formed colonies at INH concentrations inhibitory for mycolic acid biosynthesis. These mycolate-deficient M. avium exhibited altered colony morphologies, modified cell wall ultrastructure and were 10-fold more sensitive to treatment with hydrophobic antibiotics, such as rifampin. These findings may significantly impact the design of new therapeutic regimens for the treatment of infections with atypical mycobacteria.
Collapse
Affiliation(s)
- K Mdluli
- Tuberculosis Research Unit, Rocky Mountain Laboratories, National Institutes of Health, National Institutes for Allergy and Infectious Diseases, Hamilton, MT 59840, USA
| | | | | | | | | |
Collapse
|
9
|
Rastogi N, Goh KS, Bryskier A, Devallois A. Spectrum of activity of levofloxacin against nontuberculous mycobacteria and its activity against the Mycobacterium avium complex in combination with ethambutol, rifampin, roxithromycin, amikacin, and clofazimine. Antimicrob Agents Chemother 1996; 40:2483-7. [PMID: 8913450 PMCID: PMC163561 DOI: 10.1128/aac.40.11.2483] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The spectrum of activity of levofloxacin was initially determined against 29 strains belonging to 16 species of atypical mycobacteria by measuring radiometric MICs. Levofloxacin MICs were 1 to 2 dilutions lower compared with those obtained for ofloxacin and 8 to 64 dilutions lower compared with those obtained for its D-isomer. Levofloxacin MICs were below its peak level in serum (5.5 micrograms/ml following administration of a single oral dose of 350 mg) for 25 of 29 isolates tested. It possessed MICs below its peak level in serum for M. scrofulaceum, M. szulgai, M. malmoense, M. xenopi, M. marinum, M. kansasii, M. chelonei, M. abcessus, M. fortuitum, and M. peregrinum. Regarding the M. avium complex, the MICs of levofloxacin for 11 clinical isolates (7 from human immunodeficiency virus-positive patients and 4 from human immunodeficiency virus-negative patients) were 1 to 2 dilutions lower than those of ofloxacin. Among 20 isolates belonging to 12 pathogenic mycobacterial species, the MBC/MIC ratios varied from 1 to 4 for levofloxacin and 2 to 4 for ofloxacin. When drug combinations were screened by using the radiometric x/y quotient methodology against five M. avium complex isolates, levofloxacin activity against all five isolates was enhanced by ethambutol and activity against three isolates was enhanced by clofazimine. Screening of three-drug combinations showed that the combination levofloxacin-ethambutol with a third potential anti-M. avium drug (rifampin, roxithromycin, amikacin, or clofazimine) resulted in enhanced activity for all 20 drug combinations screened.
Collapse
Affiliation(s)
- N Rastogi
- Unité de la Tuberculose et des Mycobactéries, Institut Pasteur, Pointe à Pitre, Guadeloupe, French West Indies
| | | | | | | |
Collapse
|
10
|
Rivière M, Puzo G, Wright EL, Barrow WW. A unique phenylalanine-containing lipopeptide isolated from a rough-colony variant of Mycobacterium avium. EUROPEAN JOURNAL OF BIOCHEMISTRY 1996; 241:682-90. [PMID: 8917472 DOI: 10.1111/j.1432-1033.1996.00682.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Previous investigations have suggested that the biosynthesis of the Mycobacterium avium serovar-specific glycopeptidolipid antigens involves initial steps that include the participation of lipopeptides. The prevailing assumption is that subsequent glycosylation of those lipopeptides results in the fully glycosylated form of the glycopeptidolipid components. In an effort to identify potential precursors in the biosynthetic pathway of glycopeptidolipid components, we have identified a unique lipopeptide from an M. avium rough variant (MAC702) that was isolated from a patient suffering from a chronic M. avium lung infection. Upon examination it was revealed that although the total lipid extract from MAC702 lacked serovar-specific glycopeptidolipid antigens, it did contain a unique lipopeptide, possessing some amino acids identical to those found in the serovar-specific glycopeptidolipid antigens. Initial examination of acid-hydrolyzed samples of the lipopeptide (lipopeptide-I) revealed the presence of phenylalanine, alanine, and isoleucine, but no carbohydrate. Subsequent mass spectrometric and 1H-NMR and 1H-13C-NMR correlation spectroscopy analysis confirmed the initial results and also revealed the presence of N-methylisoleucine. The following structure for lipopeptide-I was proposed: fatty acyl (C19 or C17)-Phe-N-methyl-Ile-Ile-Phe-Ala-Ile-Ala-Phe. Lipopeptide-I is unlike any heretofore identified compound, however, it does have similar features to lipopeptides previously reported in mycobacteria and fungi. Although its structure does not verify that it is a direct precursor in glycopeptidolipid biosynthesis, the presence of certain components in lipopeptide-I indicate that it may share at least some pathways associated with the biosynthesis of the M. avium serovar-specific glycopeptidolipids.
Collapse
Affiliation(s)
- M Rivière
- Institut de Pharmacologie et de Biologie Structurale, Centre National de la Recherche Scientifique, Toulouse, France
| | | | | | | |
Collapse
|
11
|
Wright EL, Zywno-van Ginkel S, Rastogi N, Barrow WW. Monoclonal infection involving Mycobacterium avium presenting with three distinct colony morphotypes. J Clin Microbiol 1996; 34:2475-8. [PMID: 8880503 PMCID: PMC229297 DOI: 10.1128/jcm.34.10.2475-2478.1996] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Recent reports indicate that polyclonal infections may play an important role in multiple drug resistance in Mycobacterium avium infections. We report here on the isolation of a single M. avium strain that appeared to have smooth colony morphology upon initial isolation on a Lowenstein-Jensen slant. Primary subculture onto Middlebrook 7H10, however, revealed three distinct morphotypes representing smooth opaque (SmO), smooth transparent (SmT), and rough (Rg) colony morphologies. All three morphotypes were identified as M. avium by standard biochemical procedures, Genprobe analysis, and mycolic acid patterns. Subsequent restriction fragment length polymorphism analysis, using SalI- and PvuII-digested genomic DNA, revealed identical patterns for hybridization with the IS1245 probe. Thin-layer chromatographic analysis of lipids from the three morphotypes revealed that only the SmT morphotype possessed what appeared to be lipid components similar to, but unlike, previously described serovar-specific glycopeptidolipid antigens. Further analysis of internally radiolabeled deacylated lipids from the SmT morphotype, by high-performance liquid chromatography and thin-layer chromatography, disclosed that some of these components can be internally radiolabeled with [14C] phenylalanine and [14C]mannose. These results suggest that these components are structurally similar to previously described glycopeptidolipid antigens. This is apparently the first report of a monoclonal infection involving a single strain of M. avium presenting with all three colony morphotypes, SmO, SmT, and Rg.
Collapse
Affiliation(s)
- E L Wright
- Mycobacteriology Research Unit, Southern Research Institute, Birmingham, Alabama 35205, USA
| | | | | | | |
Collapse
|
12
|
Rastogi N, Goh KS, Van Ginkel SZ, Wright EL, Barrow WW. Identification of new drug targets in Mycobacterium avium and Mycobacterium tuberculosis. Res Microbiol 1996; 147:97-105. [PMID: 8761729 DOI: 10.1016/0923-2508(96)80210-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- N Rastogi
- Unité de la Tuberculose et des Mycobactéries, Institut Pasteur de la Guadeloupe, Pointe-à-Pitre, Guadeloupe, French West Indies
| | | | | | | | | |
Collapse
|
13
|
Barrow WW, Davis TL, Wright EL, Labrousse V, Bachelet M, Rastogi N. Immunomodulatory spectrum of lipids associated with Mycobacterium avium serovar 8. Infect Immun 1995; 63:126-33. [PMID: 7806348 PMCID: PMC172968 DOI: 10.1128/iai.63.1.126-133.1995] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Lipid fractions obtained from Mycobacterium avium serovar 8 were assessed for the ability to affect various immune functions of human peripheral blood mononuclear cells (PBM). Lipids included a total lipid fraction and fractions eluted from silicic acid column separation of that total lipid fraction, using chloroform and chloroform-methanol combinations. Lipid fractions were assayed for total carbohydrate and total 6-deoxyhexose content and were assessed for the ability to influence human macrophage function and the capacity to induce secretion of prostaglandin E2 (PGE2) and tumor necrosis factor alpha in PBM. The total lipid and serovar-specific glycopeptidolipid (GPL) fractions both induced significant levels of tumor necrosis factor alpha, as well as PGE2, in PBM exposed to a sublethal concentration of 100 micrograms lipid per 2 x 10(6) cells. In addition, the same concentrations of the 5 to 7% and GPL fractions induced significant levels of leukotriene B4 in PBM. Comparison of carbohydrate and 6-deoxyhexose contents of each fraction suggested a relationship to carbohydrate content and ability of fractions to induce immune modulator secretion. Analysis of GPL fractions from M. avium serovars 4 and 20 revealed that those GPL lacked the ability to induce PGE2. These results are explained by considering the difference in the carbohydrate residues of the oligosaccharide moieties.
Collapse
Affiliation(s)
- W W Barrow
- Unité de la Tuberculose et des Mycobactéries, Institut Pasteur, Pointe-à-Pitre, Guadeloupe, French West Indies
| | | | | | | | | | | |
Collapse
|
14
|
Rastogi N, Goh KS, Wright EL, Barrow WW. Potential drug targets for Mycobacterium avium defined by radiometric drug-inhibitor combination techniques. Antimicrob Agents Chemother 1994; 38:2287-95. [PMID: 7840559 PMCID: PMC284732 DOI: 10.1128/aac.38.10.2287] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Previously established radiometric techniques were used to assess the effectiveness of combined antimicrobial drug-inhibitory drug (drug-inhibitor) treatment on two clinical isolates of the Mycobacterium avium complex representing three colony variants: smooth opaque (dome) (SmO), smooth transparent (SmT), and rough (Rg). All variants were identified as members of the M. avium complex; however, only the SmT colony type of strain 373 possessed characteristic serovar-specific glycopeptidolipid (GPL) antigens. MICs, determined radiometrically, of drugs with the potential to inhibit the biosynthesis of GPL antigens or other cell envelope constituents were similar for all strains. These drugs included cerulenin, N-carbamyl-DL-phenylalanine, N-carbamyl-L-isoleucine, trans-cinnamic acid, ethambutol, 1-fluoro-1-deoxy-beta-D-glucose, 2-deoxy-D-glucose, and m-fluoro-phenylalanine. The MICs of the antimicrobial drugs amikacin, sparfloxacin, and clarithromycin varied, but overall the MICs for the SmO variant were the lowest. Radiometric assessment of drug-inhibitor combinations by using established x/y determinations revealed enhanced activity when either ethambutol or cerulenin were used in combination with all antimicrobial agents for all variants except the Rg variant of strain 424, for which ethambutol was not effective. Enhanced activity with amino acid analogs was observed with the Rg colony variants of strains 373 and 424. Two potential sites for drug targeting were identified: fatty acid synthesis, for all strains assayed, and peptide biosynthesis, particularly for Rg colony variants that possess previously identified phenylalanine-containing lipopeptides as potential targets for future drug development.
Collapse
Affiliation(s)
- N Rastogi
- Unité de la Tuberculose et des Mycobactéries, Institut Pasteur de la Guadeloupe, French West Indies
| | | | | | | |
Collapse
|
15
|
Inderlied CB, Barbara-Burnham L, Wu M, Young LS, Bermudez LE. Activities of the benzoxazinorifamycin KRM 1648 and ethambutol against Mycobacterium avium complex in vitro and in macrophages. Antimicrob Agents Chemother 1994; 38:1838-43. [PMID: 7986017 PMCID: PMC284646 DOI: 10.1128/aac.38.8.1838] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
KRM 1648 is a 4-aminobenzoxazine derivative of rifamycin S with potent in vitro activity against the Mycobacterium avium complex (MAC); the MIC for 90% of 24 MAC isolates from AIDS patients was 0.25 microgram/ml as determined by a radiometric broth macrodilution assay. KRM 1648 was bactericidal for MAC isolates in Middlebrook 7H9 broth, with a reduction in viability of 1 to 4 orders of magnitude over 72 h. In human macrophages, KRM 1648 also was bactericidal, with a reduction of 3 to 4 orders of magnitude in CFU per ml of macrophage lysate at a concentration of 1 microgram/ml; however, the bactericidal activity varied approximately 10-fold among the three MAC serovars tested. In growth medium, ethambutol potentiated the effect of KRM 1648, but this potentiation was modest when tested against MAC in macrophages and also varied between MAC strains. KRM 1648 has potential as an antimycobacterial agent for MAC disease, perhaps in combination with other agents so that the use of lower dosages of KRM 1648 than are needed with other rifamycins may be possible.
Collapse
Affiliation(s)
- C B Inderlied
- Department of Pathology and Laboratory Medicine, Children's Hospital Los Angeles, University of Southern California 90027
| | | | | | | | | |
Collapse
|
16
|
Rastogi N, Barrow WW. Cell envelope constituents and the multifaceted nature of Mycobacterium avium pathogenicity and drug resistance. Res Microbiol 1994; 145:243-52; discussion 252-61. [PMID: 7809479 DOI: 10.1016/0923-2508(94)90025-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- N Rastogi
- Laboratoire de la Tuberculose et des Mycobactéries, Institut Pasteur, Pointe à Pitre, Guadeloupe, French West Indies
| | | |
Collapse
|
17
|
Barrow WW, de Sousa JP, Davis TL, Wright EL, Bachelet M, Rastogi N. Immunomodulation of human peripheral blood mononuclear cell functions by defined lipid fractions of Mycobacterium avium. Infect Immun 1993; 61:5286-93. [PMID: 8225602 PMCID: PMC281313 DOI: 10.1128/iai.61.12.5286-5293.1993] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Mycobacterial fractions, some of which are associated with the cell envelope of Mycobacterium avium serovar 4, were assessed for their ability to affect various immunological functions of human peripheral blood mononuclear cells (PBM). Treatment of PBM with a total lipid fraction derived from M. avium serovar 4 resulted in a significant suppression of lymphoproliferative responsiveness to phytohemagglutinin stimulation at concentrations not affecting cell viability. Although a similar suppression was not observed when PBM were treated with purified serovar 4-specific glycopeptidolipids (GPL), treatment with the beta-lipid fragment derived from the GPL did result in a significant suppression of phytohemagglutinin responsiveness. Further studies revealed that the total lipid fraction and the beta-lipid fragment were effective at significantly reducing the ability of human macrophages to restrict the intracellular growth of mycobacteria and at stimulating PBM to secrete prostaglandin E2. These same effects were not observed when purified GPL or the reduced oligosaccharide fragment of the GPL was used. Other studies revealed that the total lipid and purified GPL fractions were effective at stimulating tumor necrosis factor alpha release from human PBM, whereas the beta-lipid fragment was not. These results indicate that mycobacterial lipids have various immunomodulatory capabilities, depending upon their chemical nature and ability to interact with certain host cells.
Collapse
Affiliation(s)
- W W Barrow
- Unité de la Tuberculose et des Mycobactéries, Institut Pasteur, Paris, France
| | | | | | | | | | | |
Collapse
|