Elemi (Protium, Boswellia Frereana)
A Suggested Substitute for Canada Balsam as a Mounting Medium
The effect of Canada balsam on the more delicate stains is known only too well to those interested in histology. In my opinion this is due mainly to the 63 per cent. of higher organic acids contained in this balsam. In 1920 and the early part of 1921 efforts were made, but in vain, to obtain a neutralised non-crystalline solution of Canada balsam in xylol, by neutralising with various inorganic and organic bases. The literature concerning other oleoresins was therefore consulted with a view to finding a substitute for Canada balsam, and it was found that a species of Elemi-that from Yucatan-contained no organic acids, but 60-70 per cent. neutral amorphous resenes besides volatile oil and amyrin.
Yucatan Elemi with the amyrins removed by the above method is therefore recommended as a substitute for Canada balsam as a mounting medium for the following reasons:(1) It contains no organic acids but consists practically of neutral resenes.(2) Complete solubility in alcohol, xylol, benzene, etc.(3) A comparable refractive index.(4) Its good drying and setting properties.(5) Some sections stained with Giemsa’s stain two years previously havethe colours still unimpaired, mounted in this medium.(6) Its relative cheapness: the crude mountant can be purchased fromThe British Drug Houses Ltd. for about 2s. 6d. a lb., and this should yieldabout 60 per cent. of neutral resene.
Anti-Inflammatory Activity of Triterpenes Isolated from Protium paniculatum Oil-Resins
Protium is the main genus of the Burseraceae family and one of the most common genera in South America, with an important species called Òbreu.Ó Gum and oil-resins of this species are used as tonic and stimulant and for the treatment of ulcers and inflammation. The present study aims to isolate and investigate the anti-inflammatory activity of triterpene compounds isolated from oil-resin of Protium paniculatum. The pentacyclic triterpenes ?,?-amyrin, acetylated ?,?-amyrin, ?,?-amyrone, and brein/maniladiol did not alter the viability of murine J774 macrophages (IC50 > 20?µg/mL), with the exception of mixture of brein/maniladiol which showed moderate cytotoxic activity. Also it was observed that compounds at 10?µg/mL inhibited more than 80% of production of NO¥, although only ?,?-amyrin was able to inhibit the production of TNF-? (52.03 ± 2.4%). The compounds inhibited the production of IL-6 and induced the production of IL-10 in murine J774 macrophages stimulated by LPS. ?,?-Amyrone inhibited the expression of COX-2 and also inhibited the formation of paw or ear edema in rats and mice, having a quick and immediate effect. This study may provide the basis for future investigations on the therapeutic role of ?,?-amyrone in treating inflammation.
The triterpenes ?,?-amyrin, acetylated ?,?-amyrin, ?,?-amyrone, and brein/maniladiol are capable of modulating an immune response. In particular, the triterpene ?,?-amyrone showed no cytotoxic potential in J774 macrophages and exerted immunomodulatory activity at low concentrations, characterized by its inhibitory effects on the production of proinflammatory mediators such as NO¥, IL-6, and COX-2 expression and inducing the production of anti-inflammatory cytokine IL-10, and reduced paw edema induced by carrageenan in rats, as well as reducing ear edema in mice.
Boswellia frereana suppresses HGF-mediated breast cancer cell invasion and migration through inhibition of c-Met signaling
Hepatocyte growth factor (HGF) plays a pivotal role in breast cancer cell motility, invasion and angiogenesis. These pro-metastatic events are triggered through HGF coupling and activation of the c-Met receptor. Reports have demonstrated that HGF/c-Met signalling plays an important part in breast cancer progression and that their expression is linked to poor patient outcome. In the present study, we investigated the anti-metastatic potential of an extract from traditional Somalian frankincense, Boswellia frereana, on human breast cancer cells. In addition, we also examined the effect of this Boswellia frereana extract (BFE) upon HGF-mediated stimulation of the c-Met receptor.
Our findings reveal that B. frereana extract was able to significantly suppress the influence of HGF in a TNBC cell line. The anti-metastatic properties were governed by the ability of BFE to reduce HGF/c-Met signalling events through suppression of c-Met tyrosine kinase receptor phosphorylation. The true clinical value of BFE as a therapeutic modality requires substantial work; however, BFE may demonstrate the potential to be used as an adjuvant therapy in the clinical management of breast cancer metastasis in TNBC-classified patients with poor prognosis.