The effect of an oral anti-oxidant, N-Acetyl-cysteine, on inflammatory and oxidative markers in pulmonary sarcoidosis.

BACKGROUND: Oxidative stress (OS) has been shown to play a role in the pathogenesis of sarcoidosis and previous studies have shown that anti-oxidants can reduce markers of oxidative stress and inflammation in the peripheral blood of sarcoidosis subjects. We investigated the effect of N-Acetyl-Cysteine (NAC) on oxidative stress and inflammatory markers in the lungs of sarcoidosis patients. METHODS: We randomized 11 sarcoidosis subjects to active therapy and 3 to placebo for 8 weeks in a double blinded study. Bronchoscopy with bronchoalveolar lavage was performed pre and post therapy. Our primary endpoint was TNF-α production from stimulated and unstimulated BAL cells. Secondary outcomes included measures of oxidative stress (GSH, 8-OHdG) levels in the BAL. In-vitro studies were also performed to assess the effect of NAC on lipopolysaccharide stimulated BAL cell production of TNF-α. RESULTS: Eight subjects in the active group and 2 in the placebo group completed the study protocol. Eight weeks of oral NAC did not have a significant impact on TNF-α levels from BAL cells in-vivo in spite of a 59% increase in BAL GSH levels. Our in vitro studies showed a significant decline in TNF-α production from LPS stimulated BAL cells treated with 5 and 10 mM of NAC. CONCLUSIONS: Oral NAC increased GSH levels but failed to suppress in-vivo TNF-α production in contrast to effects in-vitro. Anti-oxidant therapy may still play a role in the management of sarcoidosis but therapy with better bioavailability or potency is needed to suppress the lung inflammatory response.

Measurement of bacterial ingestion and killing by macrophages.

This unit presents assays that allow accurate measurement of phagocytosis and killing of bacteria by macrophages. The first basic protocol describes how to measure the ability of macrophages to ingest bacteria. Importantly, because macrophage phagocytosis entails separate binding and internalization steps, assays are described here that will also determine the extent to which bacteria bound to the macrophage are in fact internalized. Two effective methods to do this are described in alternate protocols. Both of these alternate protocols rely on enumeration of differentially labeled bacteria by fluorescence microscopy to distinguish intracellular from extracellular bacteria. The unit also presents two protocols to measure the ability of a macrophage to kill bacteria it has internalized. The second basic is a straightforward assay in which bacterial colonies are enumerated before and after a killing period. Bactericidal activity is evidenced by reduced CFU bacteria on agar plates. Because it is critical to remove residual extracellular organisms, the protocol presents two alternative steps to accomplish this: a washing procedure and a more stringent method in which cells are sedimented through sucrose. An alternate protocol describes a way to measure bacterial viability based on bacterial metabolism, in which the ability of bacterial dehydrogenases to mediate the reduction of a tetrazolium salt to purple formazan is monitored by measuring absorbance spectrophotometrically.

Disease severity, scratching, and sleep quality in patients with atopic dermatitis.

BACKGROUND: The relationship between sleep quality and disease severity in patients with atopic dermatitis has not been clearly defined. METHODS: Sleep efficiency and scratching were measured over 2 nights by polysomnography, actigraphy, and self-report in 20 adults with atopic dermatitis. Tumor necrosis factor, interleukin (IL)-6, and IL-10 were assayed from a subset of 9 participants. RESULTS: Sleep measured by actigraphy and polysomnography were strongly associated with each other. Decreased sleep efficiency was associated with increasing disease severity, scratching, and IL-6. Self-reported sleep quality and quality of life were not significantly correlated with either objective sleep measure. LIMITATIONS: Results in this pilot study await confirmation in a larger investigation. CONCLUSION: Objective measures but not self-report documented that increasing severity of atopic dermatitis results in more scratching and declining sleep quality. Our data also suggest an important relationship between sleep and IL-6.