Sodium Bituminosulfonate Used to Treat Rosacea Modulates Generation of Inflammatory Mediators by Primary Human Neutrophils

Abstract

Background Sodium bituminosulfonate is derived from naturally occurring sulphur-rich oil shale and is used for the treatment of the inflammatory skin disease rosacea. Major molecular players in the development of rosacea include the release of enzymes that process antimicrobial peptides which, together with reactive oxygen species (ROS) and vascular endothelial growth factor (VEGF), promote pro-inflammatory processes and angiogenesis. The aim of this study was to address the molecular mechanism(s) underlying the therapeutic benefit of the formulation sodium bituminosulfonate dry substance (SBDS), which is indicated for the treatment of skin inflammation, including rosacea. Methods We investigated whether SBDS regulates the expression of cytokines, the release of the antimicrobial peptide LL-37, calcium mobilization, proteases (matrix metalloproteinase, elastase, kallikrein (KLK)5), VEGF or ROS in primary human neutrophils. In addition, activity assays with 5-lipoxygenase (5-LO) and recombinant human MMP9 and KLK5 were performed. Results We observed that SBDS reduces the release of the antimicrobial peptide LL-37, calcium, elastase, ROS and VEGF from neutrophils. Moreover, KLK5, the enzyme that converts cathelicidin to LL-37, and 5-LO that produces leukotriene (LT)A 4 , the precursor of LTB 4 , were both inhibited by SBDS with an IC 50 of 7.6 µg/mL and 33 µg/mL, respectively. Conclusion Since LTB 4 induces LL-37 which, in turn, promotes increased intracellular calcium levels and thereby, ROS/VEGF/elastase release, SBDS possibly regulates the LTB 4 /LL-37/calcium – ROS/VEGF/elastase axis by inhibiting 5-LO and KLK5. Additional direct effects on other pro-inflammatory pathways such as ROS generation cannot be ruled out. In summary, SBDS reduces the generation of inflammatory mediators from human neutrophils possibly accounting for its anti-inflammatory effects in rosacea.

Antimicrobial peptides: mechanism of action, activity and clinical potential

“…LL-37 is also shown to promote the formation of neutrophil extracellular traps (NETs) [ 216 , 221 ] and stabilized neutrophil derived DNA or NETs to resist being degraded by bacterial nuclease. In addition, LL-37 induces activation of caspase-1, and processing and release of IL-1β through binding to P2X7 receptor in LPS-primed macrophages [ 222 ], and promotes ROS production in neutrophil [ 223 ].…”

Applying a risk assessment guided evaluation for verifying comprehensive two-dimensional gas chromatography to analyse complex pharmaceuticals

“…The TGA-MS measurements were performed at a STAF449 F3 Jupiter thermo-balance (Netzsch, Selb, Germany) coupled with the same mass spectrometer used for the GC × GC analysis to measure the evolved gases. A deactivated, fused silica capillary (2.5 m length, 0.1 mm internal diameter, Agilent Technologies) and heated (250 °C) interfaces on both sides of the capillary were used for the coupling [ 18 ]. The TGA measurements were executed with a sample amount between 15 and 25 mg and measured in a ceramic crucible equipped with a loose lid (pinhole 50 μm diameter).…”

“…In a previous study, we analysed sodium bituminosulfonate (SBS), an API for various pharmaceutical products that are today tentatively allocable to non-biological complex drugs (NBCDs) [ 16 – 18 ]. Its origin as the sodium salt of a sulfonated shale oil distillate presented a high chemical complexity and challenges for a comprehensive analysis.…”

Immuno-inflammatory in vitro hepatotoxicity models to assess side effects of biologicals exemplified by aldesleukin

“…CD8 + T cells were isolated via positive selection with human CD8 MicroBeads, NK cells were isolated by negative selection using the Human NK cell Isolation Kit, naïve CD4 + T cells were isolated via negative selection with the human Naive CD4 + T Cell Isolation Kit II, T reg cells were isolated with the CD4 + CD25 + Regulatory T Cell Isolation Kit by depletion of non-CD4 + T cells and positive selection of CD25 + cells, and CD14 + monocytes were isolated via positive selection with Human CD14 MicroBeads. Neutrophils were isolated directly from buffy coats via double gradient centrifugation as previously described ( 45 ). When cell culturing was needed, primary human immune cells were seeded in X-Vivo-15 medium (Lonza, Basel, Switzerland).…”