Investigation of the dermal sensitizing potential of traditional medical extracts in local lymph node assays

Identification of Potential Skin Sensitizers in Myrrh

The exudate of Commiphora myrrha (myrrh) has been known for centuries as one of the most popular natural skin remedies. The characterization and safety assessment of myrrh ingredients are challenging due to the chemical variability of commercially available sources, as well as potential adulteration. Human and animal data have reported potential concerns about myrrh as a skin sensitizer, although no specific chemical entity has been identified as a potential culprit yet. In the present work, the in chemico high-throughput method using dansylated cysteamine (HTS-DCYA) was applied to extract and fractions of myrrh samples in an attempt to identify potential skin sensitizers. Nine oxo-furanogermacranes and the sesquiterpenoid alismol were isolated as major constituents. Five of the compounds were identified as weakly to moderately reactive in HTS-DCYA and could therefore trigger the molecular initiating event leading to skin sensitization. The reactive compounds were identified as 6-oxofuranodienones (2 and 5) and methoxyfuranogermacrenones (7 and 9). The reaction adducts of 2 with DCYA was confirmed by HPLC-DAD-MS and by HPLC-MS/MS experiments. A comparison of the chemical profile of myrrh samples available in-house confirmed a certain degree of chemical variability, with compounds 1, 7, and 9 occurring in four of the six samples.

High resolution MRI for non-invasive mouse lymph node mapping

Mouse models are fundamental to the study and design of new techniques for the cancer diagnosis and treatment. The lymphatic system plays an active role in oncogenesis and metastatic disease progression. However, the in vivo identification of LNs in mice is challenging with conventional imaging modalities since the LN diameter in normal mice is 1-2 mm. Standard dissection techniques are challenging and can only provide endpoint data. Here, we describe high resolution MRI (HR-MRI) approaches for the non-invasive detection of mouse LNs in vivo. We compare in vivo non-invasive HR-MRI methods (without exogenous contrast injections) to the ex vivo dye injection methods for the identification of commonly studied LNs in both normal mice and a mouse model of pancreatic ductal adenocarcinoma (PDAC). We demonstrated the potential to use HR-MRI techniques as a non-invasive imaging assay for visualizing mouse LNs in vivo.

Effect of myrrh (Commiphora molmol) on leukocyte levels before and during healing from gastric ulcer or skin injury

Myrrh (Commiphora molmol) has been widely used as an anti-inflammatory and wound healing commercial product. As white blood cell (WBC)/leukocyte counts have been used as an indicator by clinicians to monitor progress of healing in patients, the purpose of this study was to examine effects of myrrh supplementation on blood WBC numbers before an injury and during healing. Male rats (7-8-wk-of-age) were randomly assigned to four groups. Group 1 (SIM) served as "skin injury treated + myrrh treatment (500 mg/kg/day)," Group 2 (SI) as "skin injury alone", Group 3 (GUM) as "gastric ulcer treated + myrrh treatment", and Group 4 (GU) as gastric ulcer only. Myrrh treatments (via drinking water) began 4 wk before induction of injury and continued for a 2 wk period post-injury. Baseline values for each WBC type were recorded before start of the myrrh treatments. Counts were performed again on Day 1 of the 5th wk (1-2 hr before injury) and post-injury on Days 4 and 7 of the 5th wk, and a final time on Day 4 of the 6th wk. Results showed that levels of all WBC types were significantly (P < 0.05) elevated before either injury in myrrh-treated rats (Groups 1 and 3) as compared with levels in rats in Groups 2 and 4. At all timepoints, there were neither significant differences between the values seen with rats in Groups 1 and 3, nor between those in Groups 2 and 4. Treatment with myrrh also induced an initial increase in WBC levels that persisted through the post-injury healing period. Levels of most cell types only increased in the Group 2 and 4 rats once the injury was induced, but then declined over the healing period. Since myrrh enhanced WBC levels before injury, we conclude that myrrh likely contains substances that could induce an apparent antigen-driven response. As the myrrh also helped maintain elevated WBC levels throughout the healing period, this implied it was also able to induce maturation/differentiation/activation of both myeloid and lymphoid cell types during the effector phase of the immune responses involved in wound healing.