Analysis of data on phytophotodermatitis caused by contact with the sap of plants of the genus Hogweed (<i>Heracleum</i> L.)

Abstract

The rapid spread of overgrowth of plants of the genus Hogweed, associated with their use as an agricultural fodder crop, is currently a serious problem for the Russian Federation. This process has a negative impact on the biodiversity of the vegetation cover, destroying natural ecosystems and causing significant economic damage. However, the active spread of hogweeds on the territory of the Russian Federation would not be so catastrophic if it were not for their aggressive properties: in contact with the skin, plant sap causes phytophotodermitis, which is a burn similar to thermal burns of I, II and III degrees. The article considers qualitative and quantitative composition of the main biologically active substances of hogweeds sap and shows that the biologically active substances causing phytophotodermatitis are furanocoumarins. It has been established that the pronounced photosensitizing activity of furanocoumarins is determined by the presence of a furan ring at positions 6,7 and 7,8 of coumarin. Such compounds include psoralen and its main derivatives: xanthotoxin, bergapten, bergamotin, imperatorin, isopimpinellin and angelicin (isopsoralen) and its main derivatives: sfondin, pimpinellin, isobergapten. Substitution of furan ring condensed with coumarin ring as well as change of its position leads to loss of photosensitizing activity. It was determined that the activity of plant sap of the genus Hogweed is in direct dependence on such factors as qualitative and quantitative content of furanocoumarins in the plant sap, the amount of sap and the area of the skin lesion zone, the time of contact of the affected skin areas with the plant sap, the intensity of ultraviolet irradiation and the time of its effect on the affected areas, as well as the peculiarities of each person (e.g., age, skin phototype). The methods of standard therapy of three clinical forms of phytophotodermatitis were analyzed. It was found that currently no specific clinical recommendations for the diagnostics and treatment of phytophotodermatitis resulting from contact with the sap of hogweeds. At the end of the article, the conclusion is formulated that one of current and promising tasks of pharmaceutical technology may be the development of drugs used in the treatment of burns caused by the sap of plants of the genus Hogweed, taking into account the mechanism of action of furanocoumarins.