Zinc-containing Mohs' paste affects blood flow and angiogenesis suppression

Abstract

Purpose: Mohs' paste, which is composed of zinc chloride and zinc oxide starch, is used for hemostasis of superficial malignancy in the clinical setting. We investigated the concentration of intramuscular zinc in mice after Mohs' paste application and evaluated its relationship with angiogenesis from the perspective of blood flow levels within 24 h.

Methods: Male C57BL/6JJmsSlc mice were administered single dose of Mohs' paste at 25%, 50%, and 75% after unilateral hind limb surgery, and glycerin, a viscosity modifier, was administered to the control group (0%). Hind limb blood flow levels were measured with a laser Doppler perfusion imaging system (n = 6). The amounts of intramuscular zinc and vascular endothelial growth factor-A (VEGF-A) expression were analyzed using inductively coupled plasma mass spectrometry (ICP-MS) and western blotting, respectively (n = 5 or 3).

Results: Blood flow levels were significantly decreased in the 50% group after 8 h, and significantly decreased in the 25% and 50% groups after 24 h. Intramuscular zinc was significantly increased in the 50% and 75% groups after 8 h. Western blotting showed that VEGF-A levels were significantly increased in the 25% and 50% groups after 8 h. Based on analytical experiments and biological investigation, we predicated the pharmacological effect of Mohs' paste and found over 50% of it is critical in the blood flow and angiogenesis suppression after more than 8 h of its application.

Conclusions: The results suggest that the mechanism of blood flow suppression is independent of VEGF-A levels and might suppress future angiogenesis. Our findings support that of previous studies, in which Mohs' paste was expected to induce hemostasis and suppress angiogenesis. It is an excellent ointment that facilitates hemostasis by suppressing blood flow regardless of angiogenesis, and may be apt for situations where hemostasis is required in the clinical setting.

Keywords: Angiogenesis; Hemostasis; ICP-MS; Ischemia model; Laser Doppler perfusion imaging system; Mohs’ paste.

Fig. 1

Schematic image of the experimental design on ischemic operation in the femoral artery and popliteal artery. Arrows show the sites of ligation and the femoral artery, where the attached side-branches were removed

Fig. 2

Representative laser Doppler perfusion imaging system infrared images from the hind limb ischemia mice at a depth of 2 mm from the surface pre-operation (A), and the control, 25%, and 50% application (B to D) after 24 h. The blue color indicates the part with low blood flow, and the red color indicates the part with high blood flow

Fig. 3

A Results of western blot analysis for VEGF-A in the hind limb muscle of mice administered with Mohs’ paste, B relative quantities. Modifications to the relative protein expression levels of VEGF-A were investigated via western blot analysis. GAPDH served as a loading reference. Relative protein level was expressed as the mean ± SD. **p < 0.01, compared with the control. n = 3 mice in each group