Refined Spruce Resin to Treat Chronic Wounds: Rebirth of an Old Folkloristic Therapy.

Significance: The treatment of chronic wounds results in an enormous drain on healthcare resources in terms of workload, costs, frustration, and impaired quality of life, and it presents a clinical challenge for physicians worldwide. Effective local treatment of a chronic wound has an important role, particularly in patients who are-because of their poor general condition, diminished life expectancy, or unacceptable operative risk-outside of surgical treatment. Recent Advances: Since 2002, our multidisciplinary research group has investigated the properties of Norway spruce (Picea abies) resin in wound healing and its therapeutic applications in wound care. Resin is a complex mixture of resin acids (e.g., abietic, neoabietic, dehydroabietic, pimaric, isopimaric, levopimaric, sandrakopimaric, and palustric acids) and lignans (e.g., pino-, larici-, matairesinol, and p-hydroxycinnamic acid) having substantial antimicrobial, wound-healing, and skin regeneration enhancing properties. Critical Issues: The cornerstone in successful wound care is an efficient causal treatment of the underlying co-morbidities, for example, diabetes, malnutrition, vascular- or certain systemic diseases. However, definitive diagnosis and specific therapy of a chronic wound is often difficult, because the etiology is practically always multi-factorial, and in the chronic phase, confounding factors such as infections invariably impede wound healing. Future Directions: To study the exact molecular mechanism of actions by which resin promotes cellular regeneration and epithelialization during the wound-healing process. To investigate potential antimicrobial properties of resin against the most ominous multidrug-resistant beta-lactamase (including carbapenemases and metallo-ß-lactamases) producing bacteria, and to individualize those pharmacologically active compounds which are responsible for the antimicrobial activity of resin.

Natural coniferous resin lacquer in treatment of toenail onychomycosis: an observational study.

In in vitro tests, natural coniferous resin from the Norway spruce (Picea abies) is strongly antifungal. In this observational study, we tested the clinical effectiveness of a lacquer composed of spruce resin for topical treatment of onychomycosis. Thirty-seven patients with clinical diagnosis of onychomycosis were enrolled into the study. All patients used topical resin lacquer treatment daily for 9 months. A mycological culture and potassium hydroxide (KOH) stain were done from nail samples in the beginning and in the end of the study. Treatment was considered effective, if a mycological culture was negative and there was an apparent clinical cure. At study entry, 20 patients (20/37; 54%; 95% CI: 38-70) had a positive mycological culture and/or positive KOH stain for dermatophytes. At study end, the result of 13 patients was negative (13/19; 68%; 95% CI: 48-89). In one case (1/14; 7%; 95% CI: 0-21) the mycological culture was initially negative, but it turned positive during the study period. By 14 compliant patients (14/32; 44%; 95% CI: 27-61), resin lacquer treatment was considered clinically effective: complete healing took place in three cases (9%) and partial healing in 11 cases (85%). The results indicate some evidence of clinical efficacy of the natural coniferous resin used for topical treatment of onychomycosis.

Natural coniferous resin salve used to treat complicated surgical wounds: pilot clinical trial on healing and costs.

Resin is a natural product of coniferous trees. Salves manufactured from spruce resin (Picea abies) have been used for centuries to treat wounds and skin infections. We report a pilot clinical trial designed to investigate healing rates, factors that contribute to delayed wound healing, cost-effectiveness, and incidence of allergic reactions when resin salve is used to treat complicated surgical wounds. The trial involved 23 patients in whom wound healing after surgery was delayed. These patients were assigned to resin salve treatment. The primary outcome measure was the number of days to complete wound healing. Secondary objectives included an assessment of factors contributing to delayed wound healing, an estimation of associated costs, and an investigation into the occurrence of allergic reactions related to resin salve therapy. The study achieved a healing rate of 100%. The mean ± SD healing time was 43 ± 24 days. The mean ± SD wound size (length × width × depth) was (29 ± 19) × (12 ± 7) × (4 ± 3) mm. Wound size, use of corticosteroids or other immunosuppressants, and immobilization were statistically significant (P < 0.05) contributors to delayed wound healing and impaired re-epithelialization. The total mean ± SD costs of the resin salve treatment were €45.0 ± 26.0 per patient during the entire treatment period and €1.2 ± 0.5 per treatment day. The rate of allergic reactions was 0%. The results of this pilot trial indicate that complicated surgical wounds may be treated successfully with resin salve. The treatment method is clinically effective and cost-effective, and the rate of allergic reactions is low.

Antimicrobial properties of natural coniferous rosin in the European Pharmacopoeia challenge test.

Rosins (resins) are natural products of the coniferous trees. Purified rosin from the trunk of Norway spruce (Picea abies) is antibacterial against the gram-positive bacteria, but not against the gram-negative bacteria in agar plate diffusion test. In this study, we examined the antimicrobial properties of the coniferous rosin against bacteria and yeasts using the European Pharmacopoeia (EP) challenge test. The microbes tested were Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Candida albicans. To prepare challenge media, purified rosin was mixed with a biologically inert salve in varying concentrations. The microbes were inoculated (5 × 10(5) microbes (bacteria) or 5 × 10(4) microbes (yeast, C.albicans)) into 10 g of the rosin-containing challenge medium for 14 days at maximum. Samples were taken from the media for re-cultivation of the microbes at time intervals of 1 h, 24 h, 4, 7, and 14 days. The microbicidal efficacy of the challenge media was estimated by reduction of the number of the colony forming units (CFU) of microbes in the test samples. A reduction of more than 10(3) CFU for bacteria and 10(2) CFU for fungi in 7 days was considered to indicate a significant microbicidal action. Pure rosin was antimicrobial within 24 h against all microbes tested. The 0.5% rosin-salve medium (w/w) did not differ in microbicidal effects from the rosin-free salve medium (control). A raise of the rosin concentration resulted in increase of the microbicidal effect of the rosin-salve medium against all micro-organisms tested. Rosin concentration of 10% (w/w) in the medium significantly reduced the colonization of S. aureus (including MRSA) within 24 h and significantly reduced the colonization of all other micro-organisms within 4 days. Rosin is strongly microbicidal against a wide range of microbes, against both gram-positive and gram-negative bacteria, and against C. albicans, in the EP challenge test. The minimum concentration of rosin is 10% (w/w) to prevent the preservation of the microbes in the rosin-salve media.

Effects of Norway spruce (Picea abies) resin on cell wall and cell membrane of Staphylococcus aureus.

Resin salve prepared from Norway spruce (Picea abies) has been used for centuries in traditional medicine to treat skin diseases. The authors studied with transmission and scanning electron microscopy, and with electron physiology, changes in cell wall and cell membrane of Staphylococcus aureus after exposure of the bacterial cultures to resin. After exposure, cell wall thickening, cell aggregation, changed branching of fatty acids, and dissipation of membrane potential of the bacterial cells were observed. The authors conclude that spruce resin affects the cell viability via changes in the cell wall and membrane, and impairs, thereby, the synthesis of energy in the bacteria.

Resin-salve from Norway spruce--a potential method to treat infected chronic skin ulcers?

The home-made resin salve from Norway spruce is traditionally and widely used in folk medicine to heal various skin infections and wounds in Northern Finland. We have performed laboratory studies to solve the mechanism of resin salve. The resin salve exhibited a bacteriostatic effect against all tested Gram-positive bacteria important in human medicine including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococcus (VRE), but was not effective against Gram-negative bacteria. An exception among the Gram-negative bacteria was Proteus vulgaris against which resin salve was effective. High amounts of lipophilic extractives, like resin acids were dissolved into water from the resin salve. Also, a large proportion of lignans and cinnamic acid were found in the water extract.