The use of NAC in the therapy of chronic C. pneumoniae infections is explained below. Alone, I do not think it would eradicate this pathogen. We recommend it be used in combination with other antibiotics. Take care.
ELIMINATION OF EXTRACELLULAR ELEMENTARY BODIES.
Elementary bodies are the only infectious forms of Chlamydia. During the unique life cycle of Chlamydia, extracellular elementary bodies are produced, and it is these elementary bodies that infect new host cells. Extracellular elementary bodies in healthy humans are more common than appreciated. For example, during the winter respiratory tract infection season, 33% of healthy blood donors had positive cultures for C. pneumoniae from buffy coat samples of their blood (1). Clearly these infectious elementary bodies in the systemic circulation or in any other extracellular fluids should be eliminated before they are able to infect a new host cell. Fortunately, there are unique physiochemical agents that are specifically able to eliminate these extracellular chlamydial elementary bodies. Unless these extracellular elementary bodies are eliminated in the host, antichlamydial therapy for chronic chlamydial infections must be prolonged until all of these extracellular elementary bodies have infected host cells and thus can be eliminated during their metabolically active stages. This clearly is undesirable as it prolongs the therapy of chronic chlamydial infections as well as increases the chance for resistance.
Infectious chlamydial elementary bodies can be made less infectious by the use of thiol-containing compounds. Specific thiol-containing compounds that may be effective include meso-2,3-dimercaptosuccinic acid (meso-DMSA), an oral chelating agent currently used to treat lead poisoning (2). Meso-DMSA is a weak acid with four ionizable hydrogens. Moreover, meso-DMSA has two highly charged carboxyl groups, which prevent its passage through human cell membranes. Meso-DMSA thus remains in the extracellular fluid where it readily can encounter extracellular chlamydial elementary bodies. The two thiol (sulfhydryl) groups on the succimer molecule are able to dissolve the disulfide bonds in outer membranes of extracellular chlamydial elementary bodies. For Chlamydiae, the dissolution of the outer membrane thereby initiates the transition of the elementary body form to the reticulate body form. Because this occurs in the extracellular milieu where there is no available energy source for the chlamydiae, the nascent reticulate body perishes.
Another thiol-containing compound that inhibits the infectivity of chlamydial elementary bodies is penicillamine (3). Penicillamine, D L-âˆšÃ¼, âˆšÃ¼-dimethlcysteine, is a sulfhydryl amino acid that was first isolated from the urine of patients with chronic liver disease who were receiving parenteral penicillin. Its use against chlamydial elementary bodies, however, may be somewhat curtailed by a variety of undesirable side effects (4), which do not appear to be problems with meso-DMSA.
In addition, there is an alternative method of providing a controlled release of penicillamine under physiologic conditions that provides greater safety. This simply is the use of oral penicillins as these undergo, in part, acid hydrolysis to penicillamine in the human host. Thus, oral penicillins such as amoxicillin can be used as a low-cost alternative to meso-DMSA and/or penicillamine. The in-vivo production of penicillamine from the degradation of penicillins undoubtedly accounts, in part, for the well-known in-vitro ability of penicillins to prevent the development of infectious chlamydial elementary bodies in cell cultures (5-8).
Finally, N-acetyl cysteine is another thiol-containing compound that has been safely used in humans for many years (9, 10) and also breaks down the disulfide bonds in the elementary body.
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